Background: Colon cancer is the third most common cancer and second highest cause of cancer death... more Background: Colon cancer is the third most common cancer and second highest cause of cancer deaths worldwide. The aim of the study was to find new biomarkers for diagnosis, prognosis and therapeutic drug targets for this disease.Methods: Four low-grade and four high-grade human colon adenocarcinoma tumours with patient-matched normal colon tissues were analysed. Additionally, tissue-derived primary cell lines were established from each tumour tissue. The cell lines were validated using DNA sequencing to confirm that they are a suitable in vitro model for colon adenocarcinoma based on conserved gene mutations. Label-free quantitation proteomics was performed to compare the proteomes of colon adenocarcinoma samples to normal colon samples, and of colon adenocarcinoma tissues to tissue-derived cell lines to find significantly differentially abundant proteins. The functions enriched within the differentially expressed proteins were assessed using STRING. Proteomics data was validated by...
Salivary tumours are uncommon, comprising only 2–5 per cent of head and neck neoplasms,1 with muc... more Salivary tumours are uncommon, comprising only 2–5 per cent of head and neck neoplasms,1 with mucoepidermoid carcinoma (MEC) being the most common salivary cancer in both adults and children.1–4 Clinically, head and neck MEC can present variably from being asymptomatic to locally or metastatically aggressive.5,6 Treatment is primary surgical resection with neck dissection. The use of adjuvant radiotherapy is indicated for patients at high risk of recurrence, such as those with a high tumour stage, positive resection margins and high histological grading.6–8
International Journal of Ophthalmology and Clinical Research, 2015
sensitivity to corticosteroids [1,5]. Symptoms depend on the organ(s) affected, most commonly the... more sensitivity to corticosteroids [1,5]. Symptoms depend on the organ(s) affected, most commonly the pancreas (autoimmune pancreatitis) [6], biliary system (sclerosing cholangitis) [7], lacrimal and salivary glands (Mikulicz's disease) [8]. Involvement of the orbit [9], thyroid (Riedel's thyroiditis) [10], kidneys (tubulointerstitial nephritis) [11], retroperitoneum (retroperitoneal fibrosis) [12], aorta (aortitis) [13], bowel (mesenteritis) [14], prostate [15], breast [16], lungs [17], pericardium [18], meninges [19], hypophysis [20], lymph nodes [9] and skin [21] have also been described. Any number of organs can be affected simultaneously or metachronously [5].
Head and neck sarcomas are a rare and heterogeneous group of tumors that pose management challeng... more Head and neck sarcomas are a rare and heterogeneous group of tumors that pose management challenges. We report our experience with these tumors. Forty consecutive patients treated for 44 head and neck sarcomas between 1997 and 2014 were culled from our prospectively maintained head and neck database. Five patients were excluded. The adult cohort consisted 29 (83%) patients of a mean age of 57.7 years, with 33 sarcomas. The most common diagnoses were undifferentiated pleomorphic sarcoma (27%) and chondroblastic osteosarcoma (21%). Clear surgical margins were achieved in 24/33 (73%) lesions. Twenty-two patients received radiotherapy and/or chemotherapy. Fourteen patients developed local (n = 6), regional (n = 1) and distant (n = 7) recurrence. The overall 5-year survival was 66% with a mean survival interval of 66.5 months. Recurrent sarcoma, close (<1 mm) or involved surgical margins and advanced age were associated with statistically significantly reduced survival. The pediatric ...
Background. Large oncosurgical defects of the cheek present a challenging reconstructive problem,... more Background. Large oncosurgical defects of the cheek present a challenging reconstructive problem, especially when skin resections are combined with other procedures such as parotidectomy and/or neck dissection. Methods. We present our experience with the deep plane cervicofacial flap (DPCFF) for reconstructing zone 1 (n = 7), zone 2 (n = 6), and zone 3 (n = 5) cheek defects resulting from excision of primary cutaneous malignancies (n = 13) and metastatic parotid (n = 6) and/or neck (n = 4) disease with skin involvement. The patients were between 65 and 88 years of age (mean, 76.7 years). The design of the flap was determined by the location of the defect and the need for simultaneous parotidectomy and/or neck dissection. Sixteen flaps were anteriorly based, whereas two were posteriorly based. Results. Twelve patients underwent simultaneous parotidectomy (n = 11) and/or neck dissection (n = 10) and/or facial reanimation procedures (n = 6). The size of the cutaneous defects ranged from 4 Â 4 to 10 Â 10 (mean, 5.6 Â 5.3) cm. Eight patients received postoperative adjuvant radiotherapy to the primary site and/or parotid bed and neck. Superficial marginal flap necrosis occurred in one of the three patients who received definitive radiotherapy before salvage surgery and repair with DPCFF. Other complications included one hema-toma, one ectropion, and one retraction of the lower eyelid. Apart from mild facial contour deficiency in two patients, excellent functional and cosmetic outcome with good skin color and texture match were achieved in all patients. Conclusions. The DPCFF is a versatile reconstructive technique in head and neck surgery. It provides a simple solution for a variety of cheek defects as an excellent alternative to regional or free tissue transfer. It can be used when simultaneous parotidectomy and/or neck dissection and/or facial reanimation procedures are required. This composite musculo-fasciocutaneous unit is reliable with excellent vascularity, because it has an axial blood supply. Division of the facial suspensory ligaments during elevation of the flap in the sub-superficial musculoaponeurotic system (SMAS) plane increases the mobility of this flap, which facilitates transfer.
Background. The purpose of this study was to evaluate the donor site morbidity of the free ulnar ... more Background. The purpose of this study was to evaluate the donor site morbidity of the free ulnar forearm flap (UFF). Methods. Consecutive patients undergoing free UFF between 1982 and 2009 were retrospectively reviewed. In addition, detailed assessment of hand function and donor site cosmesis was performed in the most recent 50 patients followed up for at least 12 months. Results. In all, 62 of the 242 free UFF donor sites (26%) were closed directly and the remainder required split thickness skin grafting. Donor site complications included total (n ¼ 1) and partial (n ¼ 17) skin graft loss and persistent hypertrophic scarring (n ¼ 4). There was minimal incidence of cold intolerance, parasthesia, and pain; no reduction in joint mobility, grip and pinch strength, and sensory dysfunction, with excellent donor site cosmesis. Conclusions. UFF has several advantages, including the possibility of direct closure of the donor defect, and reduced morbidity and excellent donor site cosmesis. V
Mucosal squamous cell carcinoma of the head and neck is a disease of high mortality and morbidity... more Mucosal squamous cell carcinoma of the head and neck is a disease of high mortality and morbidity. Interactions between the squamous cell carcinoma and the host's local immunity, and how the latter contributes to the biological behavior of the tumor are unclear. In vivo studies have demonstrated sequential mast cell infiltration and degranulation during squamous cell carcinogenesis. The degree of mast cell activation correlates closely with distinct phases of hyperkeratosis, dysplasia, carcinoma in-situ and invasive carcinoma. However, the role of mast cells in carcinogenesis is unclear. This study explores the effects of mast cells on the proliferation and gene expression profile of mucosal squamous cell carcinoma using human mast cell line (HMC-1) and human glossal squamous cell carcinoma cell line (SCC25). HMC-1 and SCC25 were co-cultured in a two-compartment chamber, separated by a polycarbonate membrane. HMC-1 was stimulated to degranulate with calcium ionophore A23187. The...
International journal of clinical and experimental pathology, 2019
Objectives: Vitamin D receptor (VDR) may play a role in keloid disorder. This study investigated ... more Objectives: Vitamin D receptor (VDR) may play a role in keloid disorder. This study investigated the expression of VDR by the embryonic stem cell (ESC)-like population within keloid-associated lymphoid tissues (KALTs) which expresses components of the renin-angiotensin system (RAS). Methods: 11 formalin-fixed paraffin-embedded sections of keloid lesions (KLs) underwent 3,3-diaminobenzidine (DAB) immunohistochemical (IHC) staining for VDR. Immunofluorescence (IF) dual IHC staining of CD34/VDR and OCT4/VDR was performed on two representative KLs. Transcriptional activation of VDR was investigated in four representative snap-frozen KLs using reverse-transcriptase-quantitative polymerase chain reaction (RT-qPCR). Results: DAB IHC staining demonstrated the presence of VDR on the KALTs within the keloid tissue samples. RT-qPCR confirmed transcriptional activation of VDR. IF IHC staining demonstrated expression of VDR on the CD34+ and the OCT4+ endothelium of the microvessels, and the OCT4...
There is increasing literature showing the presence of cancer stem cells (CSCs) in renal clear ce... more There is increasing literature showing the presence of cancer stem cells (CSCs) in renal clear cell carcinoma (RCCC) which is associated with poor prognosis. Characterization of CSCs may lead to better understanding and treatment of RCCC. 4μm-thick formalin-fixed paraffin-embedded RCCC samples from ten patients underwent 3,3-diaminobenzidine (DAB) immunohistochemical (IHC) staining for the embryonic stem cell (ESC) markers NANOG, SOX2, OCT4, c-MYC, KLF4 and progenitor cell marker CD44. NanoString (n = 4) and in-situ hybridization (ISH, n = 6) mRNA analyses were performed on RCCC samples to investigate transcript expression of these ESC markers. Cell counting was performed on the IHCand ISH-stained slides and statistical analyses were performed using t-tests. Immunofluorescence (IF) IHC staining was performed on two RCCC samples to localize the expression of these ESC markers. DAB IHC staining demonstrated expression of NANOG, SOX2, OCT4, c-MYC, KLF4 and CD44 in all ten RCCC samples....
The stemness-associated markers OCT4, NANOG, SOX2, KLF4 and c-MYC are expressed in numerous cance... more The stemness-associated markers OCT4, NANOG, SOX2, KLF4 and c-MYC are expressed in numerous cancer types suggesting the presence of cancer stem cells (CSCs). Immunohistochemical (IHC) staining performed on 12 lung adenocarcinoma (LA) tissue samples showed protein expression of OCT4, NANOG, SOX2, KLF4 and c-MYC, and the CSC marker CD44. In situ hybridization (ISH) performed on six of the LA tissue samples showed mRNA expression of OCT4, NANOG, SOX2, KLF4 and c-MYC. Immunofluorescence staining performed on three of the tissue samples showed co-expression of OCT4 and c-MYC with NANOG, SOX2 and KLF4 by tumor gland cells, and expression of OCT4 and c-MYC exclusively by cells within the stroma. RT-qPCR performed on five LA-derived primary cell lines showed mRNA expression of all the markers except SOX2. Western blotting performed on four LA-derived primary cell lines demonstrated protein expression of all the markers except SOX2 and NANOG. Initial tumorsphere assays performed on four LA-d...
Regulatory networks controlling cellular plasticity, important during early development, can re-e... more Regulatory networks controlling cellular plasticity, important during early development, can re-emerge after tissue injury and premalignant transformation. One such regulatory molecule is the cell surface ectoenzyme ecto-5′-nucleotidase that hydrolyzes the conversion of extracellular adenosine monophosphate to adenosine (eADO). Ecto-5′-nucleotidase (NT5E) or cluster of differentiation 73 (CD73), is an enzyme that is encoded by NT5E in humans. In normal tissue, CD73-mediated generation of eADO has important pleiotropic functions ranging from the promotion of cell growth and survival, to potent immunosuppression mediated through purinergic G protein-coupled adenosine receptors. Importantly, tumors also utilize several mechanisms mediated by CD73 to resist therapeutics and in particular, evade the host immune system, leading to undesired resistance to targeted therapy and immunotherapy. Tumor cell CD73 upregulation is associated with worse clinical outcomes in a variety of cancers. Eme...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Much work has been done to find markers of cancer stem cells (CSCs) that distinguish them from th... more Much work has been done to find markers of cancer stem cells (CSCs) that distinguish them from the tumor bulk cells and normal cells. Recent CSC research has applied the induced pluripotent stem cell (iPSC) concept. In this study, we investigated the expression of a panel of iPSC markers in primary colon adenocarcinoma (CA)-derived cell lines. Materials and methods Expression of iPSC markers by CA-derived primary cell lines was interrogated using immunocytochemistry, western blotting and RT-qPCR. The stem cell function of these cells was then assessed in vitro using differentiation and tumorsphere assays. Results Expression of iPSC markers OCT4, SOX2, NANOG, KLF4 and c-MYC was more widespread in high-grade CA (HGCA) cell lines than low-grade CA (LGCA) cell lines, as demonstrated by western blotting and RT-qPCR. These cells could be induced to differentiate down the three embryonic lineages. Cells derived from HGCA were more capable of forming tumorspheres than those derived from LGCA. EpCAM sorting revealed that a population enriched for EpCAM High cells formed larger tumorspheres than EpCAM Low cells. Pluripotency markers, SSEA4 and TRA-1-60, were co-expressed by a small subpopulation of cells that also co-expressed SOX2 in 75% and OCT4 in 50% of the cell lines. Conclusions CA-derived primary cell lines contain tumorsphere-forming cells which express key pluripotency genes and can differentiate down 3 embryonic lineages, suggesting a pluripotent CSC-like phenotype. There appear to be two iPSC-like subpopulations, one with high EpCAM expression which forms larger tumorspheres than another with low EpCAM
The cancer stem cell concept proposes that tumor growth and recurrence is driven by a small popul... more The cancer stem cell concept proposes that tumor growth and recurrence is driven by a small population of cancer stem cells (CSCs). In this study we investigated the expression of induced-pluripotent stem cell (iPSC) markers and their localization in primary low-grade adenocarcinoma (LGCA) and high-grade adenocarcinoma (HGCA) and their patientmatched normal colon samples. Materials and methods Transcription and translation of iPSC markers OCT4, SOX2, NANOG, KLF4 and c-MYC were investigated using immunohistochemical (IHC) staining, RT-qPCR and in-situ hybridization (ISH). Results All five iPSC markers were detected at the transcriptional and translational levels. Protein abundance was found to be correlated with tumor grade. Based on their protein expression within the tumors, two sub-populations of cells were identified: a NANOG + /OCT4epithelial subpopulation and an OCT4 + /NANOGstromal subpopulation. All cases were accurately graded based on four pieces of iPSC marker-related data. Conclusions This study suggests the presence of two putative sub-populations of CSCs: a NANOG + / OCT4epithelial subpopulation and an OCT4 + /NANOGstromal subpopulation. Normal colon, LGCA and HGCA could be accurately distinguished from one another using iPSC PLOS ONE |
Cancer stem cells (CSC), the putative origin of cancer, account for local recurrence and metastas... more Cancer stem cells (CSC), the putative origin of cancer, account for local recurrence and metastasis. We aimed to identify and characterize CSCs within moderately differentiated head and neck cutaneous squamous cell carcinoma (MDHNCSCC). Formalin-fixed paraffin-embedded MDHNCSCC sections of ten patients underwent 3,3-diaminobenzidine (DAB) immunohistochemical (IHC) staining for induced pluripotent stem cell (iPSC) markers OCT4, NANOG, SOX2, KLF4 and c-MYC. Localization of these markers was investigated using immunofluorescence (IF) IHC staining of three of these MDHNCSCC samples. mRNA expression of these iPSC markers in the MDHNCSCC tissue samples was determined by colorimetric in-situ hybridization (CISH, n ¼ 6), and reverse-transcription quantitative polymerase chain reaction (RT-qPCR, n ¼ 4). RT-qPCR was also performed on four MDHNCSCC-derived primary cell lines. DAB IHC staining demonstrated expression of all five iPSC markers within all ten MDHNCSCC tissues samples. CISH and RT-qPCR confirmed mRNA expression of all five iPSC markers within all MDHNCSCC tissues samples examined. RT-PCR demonstrated mRNA transcripts of all five iPSC markers in all four MDHNCSCC-derived primary cell lines. IF IHC staining showed co-expression of OCT4 with SOX2 and KLF4 throughout the tumor nests (TNs) and peritumoral stroma (PTS). There was an OCT4 þ /NANOG þ subpopulation within the TNs, and an OCT4 þ /NANOG À subpopulation and an OCT4 þ /NANOG þ subpopulation within the PTS. All iPSC markers were expressed by the endothelium of microvessels within the PTS. Our findings suggest the presence of an OCT4 þ /NANOG þ /SOX2 þ /KLF4 þ /c-MYC þ CSC subpopulation within the TNs, PTS and endothelium of microvessels within the PTS; and an OCT4 þ /NANOG À /SOX2 þ /KLF4 þ /c-MYC þ subpopulation exclusively within the PTS in MDHNCSCC. These CSC subpopulations could be a potential novel therapeutic target for treatment of MDHNCSCC.
The presence of cells within meningioma (MG) that express embryonic stem cell (ESC) markers has b... more The presence of cells within meningioma (MG) that express embryonic stem cell (ESC) markers has been previously reported. However, the precise location of these cells has yet to be determined. Methods: 3,3-Diaminobenzidine (DAB) immunohistochemical (IHC) staining was performed on 11 WHO grade I MG tissue samples for the expression of the ESC markers OCT4, NANOG, SOX2, KLF4 and c-MYC. Immunofluorescence (IF) IHC staining was performed to investigate the localization of each of these ESC markers. NanoString and colorimetric in situ hybridization (CISH) mRNA expression analyses were performed on six snap-frozen MG tissue samples to confirm transcriptional activation of these proteins, respectively. Results: DAB IHC staining demonstrated expression of OCT4, NANOG, SOX2, KLF4, and c-MYC within all 11 MG tissue samples. IF IHC staining demonstrated the expression of the ESC markers OCT4, NANOG, SOX2, KLF4, and c-MYC on both the endothelial and pericyte layers of the microvessels. NanoString and CISH mRNA analyses confirmed transcription activation of these ESC markers. Conclusion: This novel finding of the expression of all aforementioned ESC markers in WHO grade I MG infers the presence of a putative stem cells population which may give rise to MG.
Plastic and Reconstructive Surgery - Global Open, 2019
V enous malformation (VM) consists of a network of thin-walled ectatic venous channels with defic... more V enous malformation (VM) consists of a network of thin-walled ectatic venous channels with deficient media, 1 and TIE2 and PIK3CA mutations have been demonstrated. 2 Management of VM remains unsatisfactory. 2 There are 2 embryonic stem cell (ESC)-like subpopulations within subcutaneous VM (SCVM) and intramuscular VM (IMVM): one on the endothelium expressing the ESC markers NANOG, pSTAT3, OCT4, SOX2, SALL4, and CD44; and another outside the endothelium expressing NANOG, pSTAT3, SOX2, and CD44. 2 Both SCVM and IMVM express components of the renin-angiotensin system (RAS). 1 This study investigated whether the primitive subpopulations within SCVM and IMVM express the RAS. Four-micrometer-thick formalin-fixed paraffin-embedded sections of 2 representative samples each from 7 SCVM (mean age 22.9 years) and 7 IMVM (mean age 21.1 years) patients included in our previous studies, 1,2 underwent immunofluorescence (IF) immunohistochemi-From the
Aim: To investigate the expression of embryonic stem cell (ESC) markers in microcystic lymphatic ... more Aim: To investigate the expression of embryonic stem cell (ESC) markers in microcystic lymphatic malformation (mLM). Methods and Results: Cervicofacial mLM tissue samples from nine patients underwent 3,3¢-diaminobenzidine (DAB) immunohistochemical (IHC) staining for ESC markers octamer-binding protein 4 (OCT4), homeobox protein NANOG, sex determining region Y-box 2 (SOX2), Krupple-like factor (KLF4), and proto-oncogene c-MYC. Transcriptional activation of these ESC markers was investigated using real-time polymerase chain reaction (RT-qPCR) and colorimetric in situ hybridization (CISH) on four and five of these mLM tissue samples, respectively. Immunofluorescence (IF) IHC staining was performed on three of these mLM tissue samples to investigate localization of these ESC markers. DAB and IF IHC staining demonstrated the expression of OCT4, SOX2, NANOG, KLF4, and c-MYC on the endothelium of lesional vessels with abundant expression of c-MYC and SOX2, which was also present on the cells within the stroma, in all nine mLM tissue samples. RT-qPCR and CISH confirmed transcriptional activation of all these ESC markers investigated. Conclusions: These findings suggest the presence of a primitive population on the endothelium of lesional vessels and the surrounding stroma in mLM. The abundant expression of the progenitor-associated markers SOX2 and c-MYC suggests that the majority are of progenitor phenotype with a small number of ESC-like cells.
Background: Fifty percent of colorectal cancer (CRC) patients develop liver metastasis. This stud... more Background: Fifty percent of colorectal cancer (CRC) patients develop liver metastasis. This study identified and characterized cancer stem cells (CSCs) within colon adenocarcinoma metastasis to the liver (CAML). Methods: 3,3-Diaminobenzidine immunohistochemical (IHC) staining was performed on nine CAML samples for embryonic stem cell (ESC) markers OCT4, SOX2, NANOG, c-Myc, and KLF4. Immunofluorescence (IF) IHC staining was performed to investigate coexpression of two markers. NanoString mRNA expression analysis and colorimetric in situ hybridization (CISH) were performed on four snap-frozen CAML tissue samples for transcript expression of these ESC markers. Cells stained positively and negatively for each marker by IHC and CISH staining were counted and analyzed. results: 3,3-Diaminobenzidine IHC staining, and NanoString and CISH mRNA analyses demonstrated the expression of OCT4, SOX2, NANOG, c-Myc, and KLF4 within in all nine CAML samples, except for SOX2 which was below detectable levels on NanoString mRNA analysis. IF IHC staining showed the presence of a SOX2 + /NANOG + / KLF4 + /c-Myc + /OCT − CSC subpopulation within the tumor nests, and a SOX2 + /NANOG + / KLF4 + /c-Myc + /OCT4 − CSC subpopulation and a SOX2 + /NANOG + /KLF4 + /c-Myc + / OCT4 + CSC subpopulation within the peritumoral stroma. conclusion: The novel finding of three CSC subpopulations within CAML provides insights into the biology of CRC.
Plastic and Reconstructive Surgery - Global Open, 2018
The pathogenesis of Dupuytren's disease (DD) remains unclear although there is increasing evidenc... more The pathogenesis of Dupuytren's disease (DD) remains unclear although there is increasing evidence supporting the role of stem cells in this and other fibrotic conditions. This review examines the role of DD tissue-associated embryonic stem cells (ESCs) and mesenchymal stem cells (MSCs), and circulating fibrocytes and circulating MSCs, in the biology of DD. It is exciting to infer that dysfunction of an upstream ESC-like population within the affected tissue leads to the downstream development and proliferation of aberrant myofibroblasts through a putative MSC intermediate. This ESC-like population may be a potential novel therapeutic target through modulation of the renin-angiotensin system. Furthermore, circulating CD34 + fibrocytes and MSCs either derived from the bone marrow, peripheral blood cells, or DD-associated ESC-like population, may serve as potential additional extra-palmar reservoirs that undergo endothelial-to-mesenchymal transition, eventually giving rise to the aberrant myofibroblasts. Further studies examining the relative roles of these stem cells and the precise regulatory pathways that govern them may lead to novel therapy that targets these populations.
Background: Colon cancer is the third most common cancer and second highest cause of cancer death... more Background: Colon cancer is the third most common cancer and second highest cause of cancer deaths worldwide. The aim of the study was to find new biomarkers for diagnosis, prognosis and therapeutic drug targets for this disease.Methods: Four low-grade and four high-grade human colon adenocarcinoma tumours with patient-matched normal colon tissues were analysed. Additionally, tissue-derived primary cell lines were established from each tumour tissue. The cell lines were validated using DNA sequencing to confirm that they are a suitable in vitro model for colon adenocarcinoma based on conserved gene mutations. Label-free quantitation proteomics was performed to compare the proteomes of colon adenocarcinoma samples to normal colon samples, and of colon adenocarcinoma tissues to tissue-derived cell lines to find significantly differentially abundant proteins. The functions enriched within the differentially expressed proteins were assessed using STRING. Proteomics data was validated by...
Salivary tumours are uncommon, comprising only 2–5 per cent of head and neck neoplasms,1 with muc... more Salivary tumours are uncommon, comprising only 2–5 per cent of head and neck neoplasms,1 with mucoepidermoid carcinoma (MEC) being the most common salivary cancer in both adults and children.1–4 Clinically, head and neck MEC can present variably from being asymptomatic to locally or metastatically aggressive.5,6 Treatment is primary surgical resection with neck dissection. The use of adjuvant radiotherapy is indicated for patients at high risk of recurrence, such as those with a high tumour stage, positive resection margins and high histological grading.6–8
International Journal of Ophthalmology and Clinical Research, 2015
sensitivity to corticosteroids [1,5]. Symptoms depend on the organ(s) affected, most commonly the... more sensitivity to corticosteroids [1,5]. Symptoms depend on the organ(s) affected, most commonly the pancreas (autoimmune pancreatitis) [6], biliary system (sclerosing cholangitis) [7], lacrimal and salivary glands (Mikulicz's disease) [8]. Involvement of the orbit [9], thyroid (Riedel's thyroiditis) [10], kidneys (tubulointerstitial nephritis) [11], retroperitoneum (retroperitoneal fibrosis) [12], aorta (aortitis) [13], bowel (mesenteritis) [14], prostate [15], breast [16], lungs [17], pericardium [18], meninges [19], hypophysis [20], lymph nodes [9] and skin [21] have also been described. Any number of organs can be affected simultaneously or metachronously [5].
Head and neck sarcomas are a rare and heterogeneous group of tumors that pose management challeng... more Head and neck sarcomas are a rare and heterogeneous group of tumors that pose management challenges. We report our experience with these tumors. Forty consecutive patients treated for 44 head and neck sarcomas between 1997 and 2014 were culled from our prospectively maintained head and neck database. Five patients were excluded. The adult cohort consisted 29 (83%) patients of a mean age of 57.7 years, with 33 sarcomas. The most common diagnoses were undifferentiated pleomorphic sarcoma (27%) and chondroblastic osteosarcoma (21%). Clear surgical margins were achieved in 24/33 (73%) lesions. Twenty-two patients received radiotherapy and/or chemotherapy. Fourteen patients developed local (n = 6), regional (n = 1) and distant (n = 7) recurrence. The overall 5-year survival was 66% with a mean survival interval of 66.5 months. Recurrent sarcoma, close (<1 mm) or involved surgical margins and advanced age were associated with statistically significantly reduced survival. The pediatric ...
Background. Large oncosurgical defects of the cheek present a challenging reconstructive problem,... more Background. Large oncosurgical defects of the cheek present a challenging reconstructive problem, especially when skin resections are combined with other procedures such as parotidectomy and/or neck dissection. Methods. We present our experience with the deep plane cervicofacial flap (DPCFF) for reconstructing zone 1 (n = 7), zone 2 (n = 6), and zone 3 (n = 5) cheek defects resulting from excision of primary cutaneous malignancies (n = 13) and metastatic parotid (n = 6) and/or neck (n = 4) disease with skin involvement. The patients were between 65 and 88 years of age (mean, 76.7 years). The design of the flap was determined by the location of the defect and the need for simultaneous parotidectomy and/or neck dissection. Sixteen flaps were anteriorly based, whereas two were posteriorly based. Results. Twelve patients underwent simultaneous parotidectomy (n = 11) and/or neck dissection (n = 10) and/or facial reanimation procedures (n = 6). The size of the cutaneous defects ranged from 4 Â 4 to 10 Â 10 (mean, 5.6 Â 5.3) cm. Eight patients received postoperative adjuvant radiotherapy to the primary site and/or parotid bed and neck. Superficial marginal flap necrosis occurred in one of the three patients who received definitive radiotherapy before salvage surgery and repair with DPCFF. Other complications included one hema-toma, one ectropion, and one retraction of the lower eyelid. Apart from mild facial contour deficiency in two patients, excellent functional and cosmetic outcome with good skin color and texture match were achieved in all patients. Conclusions. The DPCFF is a versatile reconstructive technique in head and neck surgery. It provides a simple solution for a variety of cheek defects as an excellent alternative to regional or free tissue transfer. It can be used when simultaneous parotidectomy and/or neck dissection and/or facial reanimation procedures are required. This composite musculo-fasciocutaneous unit is reliable with excellent vascularity, because it has an axial blood supply. Division of the facial suspensory ligaments during elevation of the flap in the sub-superficial musculoaponeurotic system (SMAS) plane increases the mobility of this flap, which facilitates transfer.
Background. The purpose of this study was to evaluate the donor site morbidity of the free ulnar ... more Background. The purpose of this study was to evaluate the donor site morbidity of the free ulnar forearm flap (UFF). Methods. Consecutive patients undergoing free UFF between 1982 and 2009 were retrospectively reviewed. In addition, detailed assessment of hand function and donor site cosmesis was performed in the most recent 50 patients followed up for at least 12 months. Results. In all, 62 of the 242 free UFF donor sites (26%) were closed directly and the remainder required split thickness skin grafting. Donor site complications included total (n ¼ 1) and partial (n ¼ 17) skin graft loss and persistent hypertrophic scarring (n ¼ 4). There was minimal incidence of cold intolerance, parasthesia, and pain; no reduction in joint mobility, grip and pinch strength, and sensory dysfunction, with excellent donor site cosmesis. Conclusions. UFF has several advantages, including the possibility of direct closure of the donor defect, and reduced morbidity and excellent donor site cosmesis. V
Mucosal squamous cell carcinoma of the head and neck is a disease of high mortality and morbidity... more Mucosal squamous cell carcinoma of the head and neck is a disease of high mortality and morbidity. Interactions between the squamous cell carcinoma and the host's local immunity, and how the latter contributes to the biological behavior of the tumor are unclear. In vivo studies have demonstrated sequential mast cell infiltration and degranulation during squamous cell carcinogenesis. The degree of mast cell activation correlates closely with distinct phases of hyperkeratosis, dysplasia, carcinoma in-situ and invasive carcinoma. However, the role of mast cells in carcinogenesis is unclear. This study explores the effects of mast cells on the proliferation and gene expression profile of mucosal squamous cell carcinoma using human mast cell line (HMC-1) and human glossal squamous cell carcinoma cell line (SCC25). HMC-1 and SCC25 were co-cultured in a two-compartment chamber, separated by a polycarbonate membrane. HMC-1 was stimulated to degranulate with calcium ionophore A23187. The...
International journal of clinical and experimental pathology, 2019
Objectives: Vitamin D receptor (VDR) may play a role in keloid disorder. This study investigated ... more Objectives: Vitamin D receptor (VDR) may play a role in keloid disorder. This study investigated the expression of VDR by the embryonic stem cell (ESC)-like population within keloid-associated lymphoid tissues (KALTs) which expresses components of the renin-angiotensin system (RAS). Methods: 11 formalin-fixed paraffin-embedded sections of keloid lesions (KLs) underwent 3,3-diaminobenzidine (DAB) immunohistochemical (IHC) staining for VDR. Immunofluorescence (IF) dual IHC staining of CD34/VDR and OCT4/VDR was performed on two representative KLs. Transcriptional activation of VDR was investigated in four representative snap-frozen KLs using reverse-transcriptase-quantitative polymerase chain reaction (RT-qPCR). Results: DAB IHC staining demonstrated the presence of VDR on the KALTs within the keloid tissue samples. RT-qPCR confirmed transcriptional activation of VDR. IF IHC staining demonstrated expression of VDR on the CD34+ and the OCT4+ endothelium of the microvessels, and the OCT4...
There is increasing literature showing the presence of cancer stem cells (CSCs) in renal clear ce... more There is increasing literature showing the presence of cancer stem cells (CSCs) in renal clear cell carcinoma (RCCC) which is associated with poor prognosis. Characterization of CSCs may lead to better understanding and treatment of RCCC. 4μm-thick formalin-fixed paraffin-embedded RCCC samples from ten patients underwent 3,3-diaminobenzidine (DAB) immunohistochemical (IHC) staining for the embryonic stem cell (ESC) markers NANOG, SOX2, OCT4, c-MYC, KLF4 and progenitor cell marker CD44. NanoString (n = 4) and in-situ hybridization (ISH, n = 6) mRNA analyses were performed on RCCC samples to investigate transcript expression of these ESC markers. Cell counting was performed on the IHCand ISH-stained slides and statistical analyses were performed using t-tests. Immunofluorescence (IF) IHC staining was performed on two RCCC samples to localize the expression of these ESC markers. DAB IHC staining demonstrated expression of NANOG, SOX2, OCT4, c-MYC, KLF4 and CD44 in all ten RCCC samples....
The stemness-associated markers OCT4, NANOG, SOX2, KLF4 and c-MYC are expressed in numerous cance... more The stemness-associated markers OCT4, NANOG, SOX2, KLF4 and c-MYC are expressed in numerous cancer types suggesting the presence of cancer stem cells (CSCs). Immunohistochemical (IHC) staining performed on 12 lung adenocarcinoma (LA) tissue samples showed protein expression of OCT4, NANOG, SOX2, KLF4 and c-MYC, and the CSC marker CD44. In situ hybridization (ISH) performed on six of the LA tissue samples showed mRNA expression of OCT4, NANOG, SOX2, KLF4 and c-MYC. Immunofluorescence staining performed on three of the tissue samples showed co-expression of OCT4 and c-MYC with NANOG, SOX2 and KLF4 by tumor gland cells, and expression of OCT4 and c-MYC exclusively by cells within the stroma. RT-qPCR performed on five LA-derived primary cell lines showed mRNA expression of all the markers except SOX2. Western blotting performed on four LA-derived primary cell lines demonstrated protein expression of all the markers except SOX2 and NANOG. Initial tumorsphere assays performed on four LA-d...
Regulatory networks controlling cellular plasticity, important during early development, can re-e... more Regulatory networks controlling cellular plasticity, important during early development, can re-emerge after tissue injury and premalignant transformation. One such regulatory molecule is the cell surface ectoenzyme ecto-5′-nucleotidase that hydrolyzes the conversion of extracellular adenosine monophosphate to adenosine (eADO). Ecto-5′-nucleotidase (NT5E) or cluster of differentiation 73 (CD73), is an enzyme that is encoded by NT5E in humans. In normal tissue, CD73-mediated generation of eADO has important pleiotropic functions ranging from the promotion of cell growth and survival, to potent immunosuppression mediated through purinergic G protein-coupled adenosine receptors. Importantly, tumors also utilize several mechanisms mediated by CD73 to resist therapeutics and in particular, evade the host immune system, leading to undesired resistance to targeted therapy and immunotherapy. Tumor cell CD73 upregulation is associated with worse clinical outcomes in a variety of cancers. Eme...
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
Much work has been done to find markers of cancer stem cells (CSCs) that distinguish them from th... more Much work has been done to find markers of cancer stem cells (CSCs) that distinguish them from the tumor bulk cells and normal cells. Recent CSC research has applied the induced pluripotent stem cell (iPSC) concept. In this study, we investigated the expression of a panel of iPSC markers in primary colon adenocarcinoma (CA)-derived cell lines. Materials and methods Expression of iPSC markers by CA-derived primary cell lines was interrogated using immunocytochemistry, western blotting and RT-qPCR. The stem cell function of these cells was then assessed in vitro using differentiation and tumorsphere assays. Results Expression of iPSC markers OCT4, SOX2, NANOG, KLF4 and c-MYC was more widespread in high-grade CA (HGCA) cell lines than low-grade CA (LGCA) cell lines, as demonstrated by western blotting and RT-qPCR. These cells could be induced to differentiate down the three embryonic lineages. Cells derived from HGCA were more capable of forming tumorspheres than those derived from LGCA. EpCAM sorting revealed that a population enriched for EpCAM High cells formed larger tumorspheres than EpCAM Low cells. Pluripotency markers, SSEA4 and TRA-1-60, were co-expressed by a small subpopulation of cells that also co-expressed SOX2 in 75% and OCT4 in 50% of the cell lines. Conclusions CA-derived primary cell lines contain tumorsphere-forming cells which express key pluripotency genes and can differentiate down 3 embryonic lineages, suggesting a pluripotent CSC-like phenotype. There appear to be two iPSC-like subpopulations, one with high EpCAM expression which forms larger tumorspheres than another with low EpCAM
The cancer stem cell concept proposes that tumor growth and recurrence is driven by a small popul... more The cancer stem cell concept proposes that tumor growth and recurrence is driven by a small population of cancer stem cells (CSCs). In this study we investigated the expression of induced-pluripotent stem cell (iPSC) markers and their localization in primary low-grade adenocarcinoma (LGCA) and high-grade adenocarcinoma (HGCA) and their patientmatched normal colon samples. Materials and methods Transcription and translation of iPSC markers OCT4, SOX2, NANOG, KLF4 and c-MYC were investigated using immunohistochemical (IHC) staining, RT-qPCR and in-situ hybridization (ISH). Results All five iPSC markers were detected at the transcriptional and translational levels. Protein abundance was found to be correlated with tumor grade. Based on their protein expression within the tumors, two sub-populations of cells were identified: a NANOG + /OCT4epithelial subpopulation and an OCT4 + /NANOGstromal subpopulation. All cases were accurately graded based on four pieces of iPSC marker-related data. Conclusions This study suggests the presence of two putative sub-populations of CSCs: a NANOG + / OCT4epithelial subpopulation and an OCT4 + /NANOGstromal subpopulation. Normal colon, LGCA and HGCA could be accurately distinguished from one another using iPSC PLOS ONE |
Cancer stem cells (CSC), the putative origin of cancer, account for local recurrence and metastas... more Cancer stem cells (CSC), the putative origin of cancer, account for local recurrence and metastasis. We aimed to identify and characterize CSCs within moderately differentiated head and neck cutaneous squamous cell carcinoma (MDHNCSCC). Formalin-fixed paraffin-embedded MDHNCSCC sections of ten patients underwent 3,3-diaminobenzidine (DAB) immunohistochemical (IHC) staining for induced pluripotent stem cell (iPSC) markers OCT4, NANOG, SOX2, KLF4 and c-MYC. Localization of these markers was investigated using immunofluorescence (IF) IHC staining of three of these MDHNCSCC samples. mRNA expression of these iPSC markers in the MDHNCSCC tissue samples was determined by colorimetric in-situ hybridization (CISH, n ¼ 6), and reverse-transcription quantitative polymerase chain reaction (RT-qPCR, n ¼ 4). RT-qPCR was also performed on four MDHNCSCC-derived primary cell lines. DAB IHC staining demonstrated expression of all five iPSC markers within all ten MDHNCSCC tissues samples. CISH and RT-qPCR confirmed mRNA expression of all five iPSC markers within all MDHNCSCC tissues samples examined. RT-PCR demonstrated mRNA transcripts of all five iPSC markers in all four MDHNCSCC-derived primary cell lines. IF IHC staining showed co-expression of OCT4 with SOX2 and KLF4 throughout the tumor nests (TNs) and peritumoral stroma (PTS). There was an OCT4 þ /NANOG þ subpopulation within the TNs, and an OCT4 þ /NANOG À subpopulation and an OCT4 þ /NANOG þ subpopulation within the PTS. All iPSC markers were expressed by the endothelium of microvessels within the PTS. Our findings suggest the presence of an OCT4 þ /NANOG þ /SOX2 þ /KLF4 þ /c-MYC þ CSC subpopulation within the TNs, PTS and endothelium of microvessels within the PTS; and an OCT4 þ /NANOG À /SOX2 þ /KLF4 þ /c-MYC þ subpopulation exclusively within the PTS in MDHNCSCC. These CSC subpopulations could be a potential novel therapeutic target for treatment of MDHNCSCC.
The presence of cells within meningioma (MG) that express embryonic stem cell (ESC) markers has b... more The presence of cells within meningioma (MG) that express embryonic stem cell (ESC) markers has been previously reported. However, the precise location of these cells has yet to be determined. Methods: 3,3-Diaminobenzidine (DAB) immunohistochemical (IHC) staining was performed on 11 WHO grade I MG tissue samples for the expression of the ESC markers OCT4, NANOG, SOX2, KLF4 and c-MYC. Immunofluorescence (IF) IHC staining was performed to investigate the localization of each of these ESC markers. NanoString and colorimetric in situ hybridization (CISH) mRNA expression analyses were performed on six snap-frozen MG tissue samples to confirm transcriptional activation of these proteins, respectively. Results: DAB IHC staining demonstrated expression of OCT4, NANOG, SOX2, KLF4, and c-MYC within all 11 MG tissue samples. IF IHC staining demonstrated the expression of the ESC markers OCT4, NANOG, SOX2, KLF4, and c-MYC on both the endothelial and pericyte layers of the microvessels. NanoString and CISH mRNA analyses confirmed transcription activation of these ESC markers. Conclusion: This novel finding of the expression of all aforementioned ESC markers in WHO grade I MG infers the presence of a putative stem cells population which may give rise to MG.
Plastic and Reconstructive Surgery - Global Open, 2019
V enous malformation (VM) consists of a network of thin-walled ectatic venous channels with defic... more V enous malformation (VM) consists of a network of thin-walled ectatic venous channels with deficient media, 1 and TIE2 and PIK3CA mutations have been demonstrated. 2 Management of VM remains unsatisfactory. 2 There are 2 embryonic stem cell (ESC)-like subpopulations within subcutaneous VM (SCVM) and intramuscular VM (IMVM): one on the endothelium expressing the ESC markers NANOG, pSTAT3, OCT4, SOX2, SALL4, and CD44; and another outside the endothelium expressing NANOG, pSTAT3, SOX2, and CD44. 2 Both SCVM and IMVM express components of the renin-angiotensin system (RAS). 1 This study investigated whether the primitive subpopulations within SCVM and IMVM express the RAS. Four-micrometer-thick formalin-fixed paraffin-embedded sections of 2 representative samples each from 7 SCVM (mean age 22.9 years) and 7 IMVM (mean age 21.1 years) patients included in our previous studies, 1,2 underwent immunofluorescence (IF) immunohistochemi-From the
Aim: To investigate the expression of embryonic stem cell (ESC) markers in microcystic lymphatic ... more Aim: To investigate the expression of embryonic stem cell (ESC) markers in microcystic lymphatic malformation (mLM). Methods and Results: Cervicofacial mLM tissue samples from nine patients underwent 3,3¢-diaminobenzidine (DAB) immunohistochemical (IHC) staining for ESC markers octamer-binding protein 4 (OCT4), homeobox protein NANOG, sex determining region Y-box 2 (SOX2), Krupple-like factor (KLF4), and proto-oncogene c-MYC. Transcriptional activation of these ESC markers was investigated using real-time polymerase chain reaction (RT-qPCR) and colorimetric in situ hybridization (CISH) on four and five of these mLM tissue samples, respectively. Immunofluorescence (IF) IHC staining was performed on three of these mLM tissue samples to investigate localization of these ESC markers. DAB and IF IHC staining demonstrated the expression of OCT4, SOX2, NANOG, KLF4, and c-MYC on the endothelium of lesional vessels with abundant expression of c-MYC and SOX2, which was also present on the cells within the stroma, in all nine mLM tissue samples. RT-qPCR and CISH confirmed transcriptional activation of all these ESC markers investigated. Conclusions: These findings suggest the presence of a primitive population on the endothelium of lesional vessels and the surrounding stroma in mLM. The abundant expression of the progenitor-associated markers SOX2 and c-MYC suggests that the majority are of progenitor phenotype with a small number of ESC-like cells.
Background: Fifty percent of colorectal cancer (CRC) patients develop liver metastasis. This stud... more Background: Fifty percent of colorectal cancer (CRC) patients develop liver metastasis. This study identified and characterized cancer stem cells (CSCs) within colon adenocarcinoma metastasis to the liver (CAML). Methods: 3,3-Diaminobenzidine immunohistochemical (IHC) staining was performed on nine CAML samples for embryonic stem cell (ESC) markers OCT4, SOX2, NANOG, c-Myc, and KLF4. Immunofluorescence (IF) IHC staining was performed to investigate coexpression of two markers. NanoString mRNA expression analysis and colorimetric in situ hybridization (CISH) were performed on four snap-frozen CAML tissue samples for transcript expression of these ESC markers. Cells stained positively and negatively for each marker by IHC and CISH staining were counted and analyzed. results: 3,3-Diaminobenzidine IHC staining, and NanoString and CISH mRNA analyses demonstrated the expression of OCT4, SOX2, NANOG, c-Myc, and KLF4 within in all nine CAML samples, except for SOX2 which was below detectable levels on NanoString mRNA analysis. IF IHC staining showed the presence of a SOX2 + /NANOG + / KLF4 + /c-Myc + /OCT − CSC subpopulation within the tumor nests, and a SOX2 + /NANOG + / KLF4 + /c-Myc + /OCT4 − CSC subpopulation and a SOX2 + /NANOG + /KLF4 + /c-Myc + / OCT4 + CSC subpopulation within the peritumoral stroma. conclusion: The novel finding of three CSC subpopulations within CAML provides insights into the biology of CRC.
Plastic and Reconstructive Surgery - Global Open, 2018
The pathogenesis of Dupuytren's disease (DD) remains unclear although there is increasing evidenc... more The pathogenesis of Dupuytren's disease (DD) remains unclear although there is increasing evidence supporting the role of stem cells in this and other fibrotic conditions. This review examines the role of DD tissue-associated embryonic stem cells (ESCs) and mesenchymal stem cells (MSCs), and circulating fibrocytes and circulating MSCs, in the biology of DD. It is exciting to infer that dysfunction of an upstream ESC-like population within the affected tissue leads to the downstream development and proliferation of aberrant myofibroblasts through a putative MSC intermediate. This ESC-like population may be a potential novel therapeutic target through modulation of the renin-angiotensin system. Furthermore, circulating CD34 + fibrocytes and MSCs either derived from the bone marrow, peripheral blood cells, or DD-associated ESC-like population, may serve as potential additional extra-palmar reservoirs that undergo endothelial-to-mesenchymal transition, eventually giving rise to the aberrant myofibroblasts. Further studies examining the relative roles of these stem cells and the precise regulatory pathways that govern them may lead to novel therapy that targets these populations.
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