Gynaecological cancers are among the leading causes of cancer-related death among women worldwide... more Gynaecological cancers are among the leading causes of cancer-related death among women worldwide. Cancer cells undergo metabolic reprogramming to sustain the production of energy and macromolecules required for cell growth, division and survival. Emerging evidence has provided significant insights into the integral role of fatty acids on tumourigenesis, but the metabolic role of high endogenous oestrogen levels and increased gynaecological cancer risks, notably in obesity, is less understood. This is becoming a renewed research interest, given the recently established association between obesity and incidence of many gynaecological cancers, including breast, ovarian, cervical and endometrial cancers. This review article, hence, comprehensively discusses how FA metabolism is altered in these gynaecological cancers, highlighting the emerging role of oestradiol on the actions of key regulatory enzymes of lipid metabolism, either directly through its classical ER pathways, or indirectl...
Exosomes and liposomes are vesicular nanoparticles that can encapsulate functional cargo. The che... more Exosomes and liposomes are vesicular nanoparticles that can encapsulate functional cargo. The chemical similarities between naturally occurring exosomes and synthetic liposomes have accelerated the development of exosome mimetics as a therapeutic drug delivery platform under physiological and pathological environments. To maximise the applications of exosomes and liposomes in the clinical setting, it is essential to look into their basic chemical properties and utilise these characteristics to optimise the preparation, loading, modification and hybridisation. This review summarises the chemical and biological properties of both exosomal and liposomal systems as well as some of the challenges related to their production and application. This article concludes with a discussion on potential perspectives for the integration of exosomal and liposomal technologies in mapping better approaches for their biomedical use, especially in therapeutics.
The use of nanocarriers to improve the delivery and efficacy of antimetastatic agents is less exp... more The use of nanocarriers to improve the delivery and efficacy of antimetastatic agents is less explored when compared to cytotoxic agents. This study reports the entrapment of an antimetastatic Signal Transducer and Activator of Transcription 3 (STAT3) dimerization blocker, Stattic (S) into a chitosan-coated-poly(lactic-co-glycolic acid) (C-PLGA) nanocarrier and the improvement on the drug's physicochemical, in vitro and in vivo antimetastatic properties post entrapment. Methods: In vitro, physicochemical properties of the Stattic-entrapped C-PLGA nanoparticles (S@C-PLGA) and Stattic-entrapped PLGA nanoparticles (S@PLGA, control) in terms of size, zeta potential, polydispersity index, drug loading, entrapment efficiency, Stattic release in different medium and cytotoxicity were firstly evaluated. The in vitro antimigration properties of the nanoparticles on breast cancer cell lines were then studied by Scratch assay and Transwell assay. Study on the in vivo antitumor efficacy and antimetastatic properties of S@C-PLGA compared to Stattic were then performed on 4T1 tumor bearing mice. Results: The S@C-PLGA nanoparticles (141.8 ± 2.3 nm) was hemocompatible and exhibited low Stattic release (12%) in plasma. S@C-PLGA also exhibited enhanced in vitro anticell migration potency (by >10-fold in MDA-MB-231 and 5-fold in 4T1 cells) and in vivo tumor growth suppression (by 33.6%) in 4T1 murine metastatic mammary tumor bearing mice when compared to that of the Stattic-treated group. Interestingly, the number of lung and liver metastatic foci was found to reduce by 50% and 56.6%, respectively, and the average size of the lung metastatic foci was reduced by 75.4% in 4T1 tumor-bearing mice treated with S@C-PLGA compared to Stattic-treated group (p < 0.001). Conclusion: These findings suggest the usage of C-PLGA nanocarrier to improve the delivery and efficacy of antimetastatic agents, such as Stattic, in cancer therapy.
Cell motility is a critical step in the metastasis cascade. However, the role of cancer-associate... more Cell motility is a critical step in the metastasis cascade. However, the role of cancer-associated fibroblasts (CAFs) in facilitating endometrial cancer (EC) cell motility remains unclear. The present study aimed to investigate the role of CAFs in EC motility in a 3D environment. A co-culture model was established using an EC cell line (ECC-1) and CAFs on a Matrigel ® matrix and compared to the respective individual monocultures. It was demonstrated that endometrial CAFs increased the motility of the EC cell line, compared with the monoculture. Using live cell imaging, CAFs were observed to form cell projections that served as contact guidance for ECC-1 cell locomotion in the spheroid formation process. These effects were specific to CAFs, as fibroblasts isolated from benign endometrial tissue samples did not form cell projections. Molecular analysis revealed that RhoA/Rho-associated, coiled-coil containing protein kinase 1 (ROCK1) signaling activation partly contributed to CAF-mediated ECC-1 cell migration. The presence of Matrigel ® increased the mRNA expression of RhoA, and the mRNA and protein expression levels of its downstream effectors, ROCK1 and p-MLC, respectively, in the ECC-1 and CAF co-culture, as well as the ECC-1 and CAF monocultures. Interestingly, high phosphorylation levels of myosin light chain mediated the activation of RhoA/ROCK1 signaling in the ECC-1 and CAF co-culture. The ROCK1 inhibitor Y-27632 attenuated the motility of tumor cells in ECC-1 and CAF co-cultures. However, similar treatment led to a significant inhibition in the motility of the CAF monoculture, but not the ECC-1 monoculture. Moreover, tumor spheroid formation was inhibited due to a reduction in stress fiber formation in ECC-1 and CAF co-cultures. Altogether, these findings suggest that the regulation of the RhoA/ROCK1 signaling pathway is required for CAFs to serve as cellular vehicles in order for EC cells to migrate and form spheroids in a 3D environment.
Background Hereditary ataxia (HA) represents a group of genetically heterogeneous neurodegenerati... more Background Hereditary ataxia (HA) represents a group of genetically heterogeneous neurodegenerative diseases caused by dysfunction of the cerebellum or disruption of the connection between the cerebellum and other areas of the central nervous system. Phenotypic manifestation of HA includes unsteadiness of stance and gait, dysarthria, nystagmus, dysmetria and complaints of clumsiness. There are no specific treatments for HA. Management strategies provide supportive treatment to reduce symptoms. Objectives This systematic review aimed to identify, evaluate and summarise the published literature on the therapeutic roles of natural remedies in the treatment of HA to provide evidence for clinical practice. Methods A systematic literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Web of Science, PubMed and Science Direct Scopus were thoroughly searched for relevant published articles from June 2007 to July 2020. Results Ten...
Social isolation, magnified by the restriction of movement order during the COVID-19 pandemic, ma... more Social isolation, magnified by the restriction of movement order during the COVID-19 pandemic, may lead to negative psychosocial health impacts among community-dwelling older adults. We, therefore, aimed to evaluate recruitment rates, data collection, and group exercises conducted through virtual technology among individuals aged 60 years and over in Malaysia. Participants were recruited from the Promoting Independence in Seniors with Arthritis (PISA) pilot cohort through social media messaging. A four-week course of virtual group exercise was offered. Anxiety and depression were assessed with the Hospital Anxiety and Depression Scale (HADS) during the last attended follow-up of the cohort study (pre-pandemic), pre-intervention, and post-intervention. Exercise adherence was recorded using diaries with daily entries and attendance to the virtual group exercise sessions were also captured electronically daily. The outcomes of interest were changes in anxiety and depression scores from...
Cancer is a major health issue, conferring to more than 14.5 million deaths worldwide. Liposomes,... more Cancer is a major health issue, conferring to more than 14.5 million deaths worldwide. Liposomes, self-assembly amphiphilic bilayer molecules, served as excellent alternative vehicles due to their ability to encapsulate both hydrophobic and hydrophilic anticancer drugs. Conventional liposomes, comprised mainly phospholipids are costineffective, unstable, and easily degraded by the external environment. In this study, we introduced PEGylated oleic acid-lecithin liposomes constructed by using C-18 monounsaturated fatty acids (oleic acid) and soy lecithin, in the presence of DOPEPEG2000 in pH7.4, above their glass transition temperature, T g , by employing the simple thin layer lipid hydration method. FTIR spectrum of oleic acid, soy lecithin, and DOPEPEG2000 was studied. The average particle size without further mechanical interference was 1102.3 nm while the zeta potential value was-18 mV, which is compatible with the zeta potential of the red blood cell. The polydispersity index (PDI) was reduced by 46.2% with the incorporation of the DOPEPEG2000. The morphological study using OPM showed the presence of spherical shape liposomes that exhibit the birefringence effect under the light field and Maltese cross under the dark field. Encapsulation of folinic acid, methotrexate, doxorubicin, or irinotecan resulted in greater than 75% encapsulation efficiency (EE). Half-maximal inhibitory concentration, IC 50 , was significantly reduced in POLL as compared to free anticancer drugs. Our data demonstrate POLL may be a promising alternative vehicle to deliver various anticancer drugs to targeted tumour sites.
Journal of Health and Translational Medicine, 2013
Genetic mutations in endometrial cancer (EC) have been extensively studied in the Western populat... more Genetic mutations in endometrial cancer (EC) have been extensively studied in the Western population but not much in Asian cohorts. This study has demonstrated that PTEN and PIK3CA mutations are commonly found in EC among Malaysian women. Following RNA extraction from 20 cancerous and 18 non-cancerous tissues, the presence of mutations in 9 exons of PTEN and 3 exons of PIK3CA genes were detected using realtime PCR, accompanied by High Resolution Melt (HRM) analysis. Sequencing confirmed specificity of each PCR product. The mutations for both genes were detected in the samples with varying frequencies. Notably, all samples expressed mutation of PTEN at exon 7 but none in exon 4. Further analysis demonstrated that strong concurrent mutations occurred between exons 7 of PTEN with exon 20 region 1 of PIK3CA gene (90%). Our data showed mutations are present in EC and not the non-cancerous tissues. Larger samples are being collected to validate this observation.
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and inclu... more Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and includes squamous cell carcinomas of the oropharynx and oral cavity. Patient prognosis has remained poor for decades and molecular targeted therapies are not in routine use. Here we showed that the overall expression of collagen subunit genes was higher in cancer-associated fibroblasts (CAFs) than normal fibroblasts. Focusing on collagen8A1 and collagen11A1, we showed that collagen is produced by both CAFs and tumour cells, indicating that HNSCCs are collagen-rich environments. We then focused on discoidin domain receptor 1 (DDR1), a collagen-activated receptor tyrosine kinase, and showed that it is over-expressed in HNSCC tissues. Further, we demonstrated that collagen promoted the proliferation and migration of HNSCC cells and attenuated the apoptotic response to cisplatin. Knockdown of DDR1 in HNSCC cells demonstrated that these tumour-promoting effects of collagen are mediated by DDR1. Ou...
Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries. Annonac... more Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries. Annonacin, a natural pure compound extracted from the seeds of Annona muricata, is a potential alternative therapeutic agent to treat EC. To study the antitumor activity of annonacin and its mechanism of action in EC cells (ECCs). Viability of ECCs treated with annonacin for 72 h was determined using methyl thiazolyl tetrazolium assay. The induction of cell cycle arrest and apoptotic cell death was evaluated using propidium iodide and annexin V-PE/7-AAD assay, respectively. DNA strand breaks were visualized using transferase dUTP nick end labeling assay, and the effects of annonacin on survival signaling were determined using western blotting. Annonacin exhibited antiproliferative effects on EC cell lines (ECC-1 and HEC-1A) and primary cells (EC6-ept and EC14-ept) with EC50values ranging from 4.62 to 4.92 μg/ml. EC cells were shown arrested at G2/M phase after treated with 4 μg/ml of annonacin ...
Public reporting burden for this collection of information is estimated to average 1 hour per res... more Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.
Cancer-associated fibroblasts (CAFs) secrete various pro-tumorigenic cytokines, yet the role of t... more Cancer-associated fibroblasts (CAFs) secrete various pro-tumorigenic cytokines, yet the role of these cytokines in the progression of endometrial cancer remains unclear. We found that CAFs isolated from human endometrial cancer (EC) tissues secreted high levels of interleukin-6 (IL-6), which promotes EC cell proliferation in vitro. Neutralizing IL-6 in CAF-conditioned media reduced (47% inhibition) while IL-6 recombinant protein increased cell proliferation (~2.4 fold) of both EC cell lines and primary cultures. IL-6 receptors (IL-6R and gp130) were expressed only in EC epithelial cells but not in CAF, indicating a one-way paracrine signaling. In the presence of CAF-conditioned media, Janus kinase/signal transducers and activators of transcription (JAK/STAT3) pathway was activated in EC cells. Treatment with JAK and STAT3 specific inhibitors, AD412 and STATTIC, respectively, significantly abrogated CAF-mediated cell proliferation, indicating the role of IL-6 activation in EC cell pr...
Pancreatic stellate cells (PSC), a prominent stromal cell, contribute to the progression of pancr... more Pancreatic stellate cells (PSC), a prominent stromal cell, contribute to the progression of pancreatic ductal adenocarcinoma (PDAC). We aim to investigate the mechanisms by which PSC promote cell proliferation in PDAC cell lines, BxPC-3 and AsPC-1. PSC-conditioned media (PSC-CM) induced proliferation of these cells in a dose-and time-dependent manner. Nrf2 protein was upregulated and subsequently, its transcriptional activity was increased with greater DNA binding activity and transcription of target genes. Downregulation of Nrf2 led to suppression of PSC-CM activity in BxPC-3, but not in AsPC-1 cells. However, overexpression of Nrf2 alone resulted in increased cell proliferation in both cell lines, and treatment with PSC-CM further enhanced this effect. Activation of Nrf2 pathway resulted in upregulation of metabolic genes involved in pentose phosphate pathway, glutaminolysis and glutathione biosynthesis. Downregulation and inhibition of glucose-6-phosphatedehydrogenase with siRNA and chemical approaches reduced PSC-mediated cell proliferation. Among the cytokines present in PSC-CM, stromal-derived factor-1 alpha (SDF-1α) and interleukin-6 (IL-6) activated Nrf2 pathway to induce cell proliferation in both cells, as shown with neutralization antibodies, recombinant proteins and signaling inhibitors. Taken together, SDF-1α and IL-6 secreted from PSC induced PDAC cell proliferation via Nrf2-activated metabolic reprogramming and ROS detoxification.
Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Cancer-associated fibroblas... more Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Cancer-associated fibroblasts (CAFs) recently demonstrated tumor-promoting roles in various cancer types, yet their implication in endometrial cancer (EC) has not been fully explored. We isolated fibroblasts (CAFs) and its epithelial counterpart from human EC tissues using CD90- and CD326-antibodies conjugated magnetic beads, respectively. We collected CAFs secretion by concentrating spent supernatants from cells growing in media containing 2% fetal bovine serum. Both human EC cell lines and primary EC epithelial cells showed increased cell proliferation in a dose-dependent manner, following treatment with CAFs secretion. This was in contrast to the growth inhibitory effects shown with secretions from normal endometrial fibroblasts. EC cells also demonstrated increased cell motility and invasiveness in response to CAFs secretion. Using cytokine array and ELISA, we further identified several cytokines which were overexpressed in CAFs compared to normal endometrial fibroblasts: macrophage chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), growth regulated oncogene (GRO), regulated on activation, normal T cell expressed and secreted (RANTES) and vascular endothelial growth factor (VEGF). These cytokines may activate MAPK/Erk and/or PI3K/Akt pathways to promote EC cell proliferation, as shown by immunoblotting and ELISA. Indeed, CAFs-mediated EC proliferation was suppressed independently by specific inhibitors for PI3K/Akt (LY294002) and MAPK/Erk (U0126). To determine if CAFs promote EC tumor proliferation in vivo, we inoculated fluorescently labeled-epithelial cell and CAFs subcutaneously at the flank of nude mice in the ratio of 1:2 and 1:4. Tumor sizes were measured twice a week using calipers and monitored weekly using in vivo imaging. Inoculation of CAFs and normal fibroblasts alone did not induce any tumor growth; however, co-injection of EC with CAFs (1:4) showed approximately 3 times higher growth rate when compared to EC alone. More interestingly, there was no sign of tumor growth in mice inoculated with combination of EC and normal fibroblasts (1:4) at the end of experiment. Taken together, our data suggests that CAFs exert tumor-promoting effects both in vitro and in vivo partly via specific cytokines-mediated activation of MAPK/Erk and PI3K/Akt pathways. Delineating the roles of CAFs in EC tumor microenvironment may provide potential therapeutic targets for the treatment of EC. Citation Format: Ivy Chung, Kavita S. Subramaniam, Seng Tian Tham, Zahurin Mohamed, Noor Azmi Mat Adenan, Yin Ling Woo. Cancer-associated fibroblasts promote endometrial cancer cell proliferation in vitro and in vivo. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1078. doi:10.1158/1538-7445.AM2014-1078
Diyabetik nefropati önemli bir morbidite ve mortalite nedeni olmanın ötesinde kardiyovasküler ned... more Diyabetik nefropati önemli bir morbidite ve mortalite nedeni olmanın ötesinde kardiyovasküler nedenlerle ölüm sıklığında ciddi bir artışı da beraberinde getirmektedir. Öncelikli amaç diyabetin tedavisi ve risk faktörlerinin kontrol altında tutulmasıdır. Diyabetik nefropatide ortaya çıkan yapısal değişiklikler tüm renal kompartmanları etkileyebilmektedir. Renal ateroskleroz ve arteriyoloskleroz diyabetiklerdeki sistemik damar lezyonlarının önemli bölümünü oluşturmaktadır. Diyabetik hastalarda iyi glisemik ve sıkı kan basıncı kontrolü ile mikrovasküler komplikasyonların önlenmesi açısından önemlidir. Sunduğumuz derlemede, giderek artan oranda bir sağlık sorunu olan diyabetik nefropati hakkında genel bilgi vermek ve bu duruma dikkati çekmek amaçlanmıştır.
Gynaecological cancers are among the leading causes of cancer-related death among women worldwide... more Gynaecological cancers are among the leading causes of cancer-related death among women worldwide. Cancer cells undergo metabolic reprogramming to sustain the production of energy and macromolecules required for cell growth, division and survival. Emerging evidence has provided significant insights into the integral role of fatty acids on tumourigenesis, but the metabolic role of high endogenous oestrogen levels and increased gynaecological cancer risks, notably in obesity, is less understood. This is becoming a renewed research interest, given the recently established association between obesity and incidence of many gynaecological cancers, including breast, ovarian, cervical and endometrial cancers. This review article, hence, comprehensively discusses how FA metabolism is altered in these gynaecological cancers, highlighting the emerging role of oestradiol on the actions of key regulatory enzymes of lipid metabolism, either directly through its classical ER pathways, or indirectl...
Exosomes and liposomes are vesicular nanoparticles that can encapsulate functional cargo. The che... more Exosomes and liposomes are vesicular nanoparticles that can encapsulate functional cargo. The chemical similarities between naturally occurring exosomes and synthetic liposomes have accelerated the development of exosome mimetics as a therapeutic drug delivery platform under physiological and pathological environments. To maximise the applications of exosomes and liposomes in the clinical setting, it is essential to look into their basic chemical properties and utilise these characteristics to optimise the preparation, loading, modification and hybridisation. This review summarises the chemical and biological properties of both exosomal and liposomal systems as well as some of the challenges related to their production and application. This article concludes with a discussion on potential perspectives for the integration of exosomal and liposomal technologies in mapping better approaches for their biomedical use, especially in therapeutics.
The use of nanocarriers to improve the delivery and efficacy of antimetastatic agents is less exp... more The use of nanocarriers to improve the delivery and efficacy of antimetastatic agents is less explored when compared to cytotoxic agents. This study reports the entrapment of an antimetastatic Signal Transducer and Activator of Transcription 3 (STAT3) dimerization blocker, Stattic (S) into a chitosan-coated-poly(lactic-co-glycolic acid) (C-PLGA) nanocarrier and the improvement on the drug's physicochemical, in vitro and in vivo antimetastatic properties post entrapment. Methods: In vitro, physicochemical properties of the Stattic-entrapped C-PLGA nanoparticles (S@C-PLGA) and Stattic-entrapped PLGA nanoparticles (S@PLGA, control) in terms of size, zeta potential, polydispersity index, drug loading, entrapment efficiency, Stattic release in different medium and cytotoxicity were firstly evaluated. The in vitro antimigration properties of the nanoparticles on breast cancer cell lines were then studied by Scratch assay and Transwell assay. Study on the in vivo antitumor efficacy and antimetastatic properties of S@C-PLGA compared to Stattic were then performed on 4T1 tumor bearing mice. Results: The S@C-PLGA nanoparticles (141.8 ± 2.3 nm) was hemocompatible and exhibited low Stattic release (12%) in plasma. S@C-PLGA also exhibited enhanced in vitro anticell migration potency (by >10-fold in MDA-MB-231 and 5-fold in 4T1 cells) and in vivo tumor growth suppression (by 33.6%) in 4T1 murine metastatic mammary tumor bearing mice when compared to that of the Stattic-treated group. Interestingly, the number of lung and liver metastatic foci was found to reduce by 50% and 56.6%, respectively, and the average size of the lung metastatic foci was reduced by 75.4% in 4T1 tumor-bearing mice treated with S@C-PLGA compared to Stattic-treated group (p < 0.001). Conclusion: These findings suggest the usage of C-PLGA nanocarrier to improve the delivery and efficacy of antimetastatic agents, such as Stattic, in cancer therapy.
Cell motility is a critical step in the metastasis cascade. However, the role of cancer-associate... more Cell motility is a critical step in the metastasis cascade. However, the role of cancer-associated fibroblasts (CAFs) in facilitating endometrial cancer (EC) cell motility remains unclear. The present study aimed to investigate the role of CAFs in EC motility in a 3D environment. A co-culture model was established using an EC cell line (ECC-1) and CAFs on a Matrigel ® matrix and compared to the respective individual monocultures. It was demonstrated that endometrial CAFs increased the motility of the EC cell line, compared with the monoculture. Using live cell imaging, CAFs were observed to form cell projections that served as contact guidance for ECC-1 cell locomotion in the spheroid formation process. These effects were specific to CAFs, as fibroblasts isolated from benign endometrial tissue samples did not form cell projections. Molecular analysis revealed that RhoA/Rho-associated, coiled-coil containing protein kinase 1 (ROCK1) signaling activation partly contributed to CAF-mediated ECC-1 cell migration. The presence of Matrigel ® increased the mRNA expression of RhoA, and the mRNA and protein expression levels of its downstream effectors, ROCK1 and p-MLC, respectively, in the ECC-1 and CAF co-culture, as well as the ECC-1 and CAF monocultures. Interestingly, high phosphorylation levels of myosin light chain mediated the activation of RhoA/ROCK1 signaling in the ECC-1 and CAF co-culture. The ROCK1 inhibitor Y-27632 attenuated the motility of tumor cells in ECC-1 and CAF co-cultures. However, similar treatment led to a significant inhibition in the motility of the CAF monoculture, but not the ECC-1 monoculture. Moreover, tumor spheroid formation was inhibited due to a reduction in stress fiber formation in ECC-1 and CAF co-cultures. Altogether, these findings suggest that the regulation of the RhoA/ROCK1 signaling pathway is required for CAFs to serve as cellular vehicles in order for EC cells to migrate and form spheroids in a 3D environment.
Background Hereditary ataxia (HA) represents a group of genetically heterogeneous neurodegenerati... more Background Hereditary ataxia (HA) represents a group of genetically heterogeneous neurodegenerative diseases caused by dysfunction of the cerebellum or disruption of the connection between the cerebellum and other areas of the central nervous system. Phenotypic manifestation of HA includes unsteadiness of stance and gait, dysarthria, nystagmus, dysmetria and complaints of clumsiness. There are no specific treatments for HA. Management strategies provide supportive treatment to reduce symptoms. Objectives This systematic review aimed to identify, evaluate and summarise the published literature on the therapeutic roles of natural remedies in the treatment of HA to provide evidence for clinical practice. Methods A systematic literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Web of Science, PubMed and Science Direct Scopus were thoroughly searched for relevant published articles from June 2007 to July 2020. Results Ten...
Social isolation, magnified by the restriction of movement order during the COVID-19 pandemic, ma... more Social isolation, magnified by the restriction of movement order during the COVID-19 pandemic, may lead to negative psychosocial health impacts among community-dwelling older adults. We, therefore, aimed to evaluate recruitment rates, data collection, and group exercises conducted through virtual technology among individuals aged 60 years and over in Malaysia. Participants were recruited from the Promoting Independence in Seniors with Arthritis (PISA) pilot cohort through social media messaging. A four-week course of virtual group exercise was offered. Anxiety and depression were assessed with the Hospital Anxiety and Depression Scale (HADS) during the last attended follow-up of the cohort study (pre-pandemic), pre-intervention, and post-intervention. Exercise adherence was recorded using diaries with daily entries and attendance to the virtual group exercise sessions were also captured electronically daily. The outcomes of interest were changes in anxiety and depression scores from...
Cancer is a major health issue, conferring to more than 14.5 million deaths worldwide. Liposomes,... more Cancer is a major health issue, conferring to more than 14.5 million deaths worldwide. Liposomes, self-assembly amphiphilic bilayer molecules, served as excellent alternative vehicles due to their ability to encapsulate both hydrophobic and hydrophilic anticancer drugs. Conventional liposomes, comprised mainly phospholipids are costineffective, unstable, and easily degraded by the external environment. In this study, we introduced PEGylated oleic acid-lecithin liposomes constructed by using C-18 monounsaturated fatty acids (oleic acid) and soy lecithin, in the presence of DOPEPEG2000 in pH7.4, above their glass transition temperature, T g , by employing the simple thin layer lipid hydration method. FTIR spectrum of oleic acid, soy lecithin, and DOPEPEG2000 was studied. The average particle size without further mechanical interference was 1102.3 nm while the zeta potential value was-18 mV, which is compatible with the zeta potential of the red blood cell. The polydispersity index (PDI) was reduced by 46.2% with the incorporation of the DOPEPEG2000. The morphological study using OPM showed the presence of spherical shape liposomes that exhibit the birefringence effect under the light field and Maltese cross under the dark field. Encapsulation of folinic acid, methotrexate, doxorubicin, or irinotecan resulted in greater than 75% encapsulation efficiency (EE). Half-maximal inhibitory concentration, IC 50 , was significantly reduced in POLL as compared to free anticancer drugs. Our data demonstrate POLL may be a promising alternative vehicle to deliver various anticancer drugs to targeted tumour sites.
Journal of Health and Translational Medicine, 2013
Genetic mutations in endometrial cancer (EC) have been extensively studied in the Western populat... more Genetic mutations in endometrial cancer (EC) have been extensively studied in the Western population but not much in Asian cohorts. This study has demonstrated that PTEN and PIK3CA mutations are commonly found in EC among Malaysian women. Following RNA extraction from 20 cancerous and 18 non-cancerous tissues, the presence of mutations in 9 exons of PTEN and 3 exons of PIK3CA genes were detected using realtime PCR, accompanied by High Resolution Melt (HRM) analysis. Sequencing confirmed specificity of each PCR product. The mutations for both genes were detected in the samples with varying frequencies. Notably, all samples expressed mutation of PTEN at exon 7 but none in exon 4. Further analysis demonstrated that strong concurrent mutations occurred between exons 7 of PTEN with exon 20 region 1 of PIK3CA gene (90%). Our data showed mutations are present in EC and not the non-cancerous tissues. Larger samples are being collected to validate this observation.
Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and inclu... more Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide and includes squamous cell carcinomas of the oropharynx and oral cavity. Patient prognosis has remained poor for decades and molecular targeted therapies are not in routine use. Here we showed that the overall expression of collagen subunit genes was higher in cancer-associated fibroblasts (CAFs) than normal fibroblasts. Focusing on collagen8A1 and collagen11A1, we showed that collagen is produced by both CAFs and tumour cells, indicating that HNSCCs are collagen-rich environments. We then focused on discoidin domain receptor 1 (DDR1), a collagen-activated receptor tyrosine kinase, and showed that it is over-expressed in HNSCC tissues. Further, we demonstrated that collagen promoted the proliferation and migration of HNSCC cells and attenuated the apoptotic response to cisplatin. Knockdown of DDR1 in HNSCC cells demonstrated that these tumour-promoting effects of collagen are mediated by DDR1. Ou...
Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries. Annonac... more Endometrial cancer (EC) is the most common gynecologic malignancy in developed countries. Annonacin, a natural pure compound extracted from the seeds of Annona muricata, is a potential alternative therapeutic agent to treat EC. To study the antitumor activity of annonacin and its mechanism of action in EC cells (ECCs). Viability of ECCs treated with annonacin for 72 h was determined using methyl thiazolyl tetrazolium assay. The induction of cell cycle arrest and apoptotic cell death was evaluated using propidium iodide and annexin V-PE/7-AAD assay, respectively. DNA strand breaks were visualized using transferase dUTP nick end labeling assay, and the effects of annonacin on survival signaling were determined using western blotting. Annonacin exhibited antiproliferative effects on EC cell lines (ECC-1 and HEC-1A) and primary cells (EC6-ept and EC14-ept) with EC50values ranging from 4.62 to 4.92 μg/ml. EC cells were shown arrested at G2/M phase after treated with 4 μg/ml of annonacin ...
Public reporting burden for this collection of information is estimated to average 1 hour per res... more Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing this collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-0188), 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number.
Cancer-associated fibroblasts (CAFs) secrete various pro-tumorigenic cytokines, yet the role of t... more Cancer-associated fibroblasts (CAFs) secrete various pro-tumorigenic cytokines, yet the role of these cytokines in the progression of endometrial cancer remains unclear. We found that CAFs isolated from human endometrial cancer (EC) tissues secreted high levels of interleukin-6 (IL-6), which promotes EC cell proliferation in vitro. Neutralizing IL-6 in CAF-conditioned media reduced (47% inhibition) while IL-6 recombinant protein increased cell proliferation (~2.4 fold) of both EC cell lines and primary cultures. IL-6 receptors (IL-6R and gp130) were expressed only in EC epithelial cells but not in CAF, indicating a one-way paracrine signaling. In the presence of CAF-conditioned media, Janus kinase/signal transducers and activators of transcription (JAK/STAT3) pathway was activated in EC cells. Treatment with JAK and STAT3 specific inhibitors, AD412 and STATTIC, respectively, significantly abrogated CAF-mediated cell proliferation, indicating the role of IL-6 activation in EC cell pr...
Pancreatic stellate cells (PSC), a prominent stromal cell, contribute to the progression of pancr... more Pancreatic stellate cells (PSC), a prominent stromal cell, contribute to the progression of pancreatic ductal adenocarcinoma (PDAC). We aim to investigate the mechanisms by which PSC promote cell proliferation in PDAC cell lines, BxPC-3 and AsPC-1. PSC-conditioned media (PSC-CM) induced proliferation of these cells in a dose-and time-dependent manner. Nrf2 protein was upregulated and subsequently, its transcriptional activity was increased with greater DNA binding activity and transcription of target genes. Downregulation of Nrf2 led to suppression of PSC-CM activity in BxPC-3, but not in AsPC-1 cells. However, overexpression of Nrf2 alone resulted in increased cell proliferation in both cell lines, and treatment with PSC-CM further enhanced this effect. Activation of Nrf2 pathway resulted in upregulation of metabolic genes involved in pentose phosphate pathway, glutaminolysis and glutathione biosynthesis. Downregulation and inhibition of glucose-6-phosphatedehydrogenase with siRNA and chemical approaches reduced PSC-mediated cell proliferation. Among the cytokines present in PSC-CM, stromal-derived factor-1 alpha (SDF-1α) and interleukin-6 (IL-6) activated Nrf2 pathway to induce cell proliferation in both cells, as shown with neutralization antibodies, recombinant proteins and signaling inhibitors. Taken together, SDF-1α and IL-6 secreted from PSC induced PDAC cell proliferation via Nrf2-activated metabolic reprogramming and ROS detoxification.
Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Cancer-associated fibroblas... more Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA Cancer-associated fibroblasts (CAFs) recently demonstrated tumor-promoting roles in various cancer types, yet their implication in endometrial cancer (EC) has not been fully explored. We isolated fibroblasts (CAFs) and its epithelial counterpart from human EC tissues using CD90- and CD326-antibodies conjugated magnetic beads, respectively. We collected CAFs secretion by concentrating spent supernatants from cells growing in media containing 2% fetal bovine serum. Both human EC cell lines and primary EC epithelial cells showed increased cell proliferation in a dose-dependent manner, following treatment with CAFs secretion. This was in contrast to the growth inhibitory effects shown with secretions from normal endometrial fibroblasts. EC cells also demonstrated increased cell motility and invasiveness in response to CAFs secretion. Using cytokine array and ELISA, we further identified several cytokines which were overexpressed in CAFs compared to normal endometrial fibroblasts: macrophage chemoattractant protein-1 (MCP-1), interleukin-6 (IL-6), growth regulated oncogene (GRO), regulated on activation, normal T cell expressed and secreted (RANTES) and vascular endothelial growth factor (VEGF). These cytokines may activate MAPK/Erk and/or PI3K/Akt pathways to promote EC cell proliferation, as shown by immunoblotting and ELISA. Indeed, CAFs-mediated EC proliferation was suppressed independently by specific inhibitors for PI3K/Akt (LY294002) and MAPK/Erk (U0126). To determine if CAFs promote EC tumor proliferation in vivo, we inoculated fluorescently labeled-epithelial cell and CAFs subcutaneously at the flank of nude mice in the ratio of 1:2 and 1:4. Tumor sizes were measured twice a week using calipers and monitored weekly using in vivo imaging. Inoculation of CAFs and normal fibroblasts alone did not induce any tumor growth; however, co-injection of EC with CAFs (1:4) showed approximately 3 times higher growth rate when compared to EC alone. More interestingly, there was no sign of tumor growth in mice inoculated with combination of EC and normal fibroblasts (1:4) at the end of experiment. Taken together, our data suggests that CAFs exert tumor-promoting effects both in vitro and in vivo partly via specific cytokines-mediated activation of MAPK/Erk and PI3K/Akt pathways. Delineating the roles of CAFs in EC tumor microenvironment may provide potential therapeutic targets for the treatment of EC. Citation Format: Ivy Chung, Kavita S. Subramaniam, Seng Tian Tham, Zahurin Mohamed, Noor Azmi Mat Adenan, Yin Ling Woo. Cancer-associated fibroblasts promote endometrial cancer cell proliferation in vitro and in vivo. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1078. doi:10.1158/1538-7445.AM2014-1078
Diyabetik nefropati önemli bir morbidite ve mortalite nedeni olmanın ötesinde kardiyovasküler ned... more Diyabetik nefropati önemli bir morbidite ve mortalite nedeni olmanın ötesinde kardiyovasküler nedenlerle ölüm sıklığında ciddi bir artışı da beraberinde getirmektedir. Öncelikli amaç diyabetin tedavisi ve risk faktörlerinin kontrol altında tutulmasıdır. Diyabetik nefropatide ortaya çıkan yapısal değişiklikler tüm renal kompartmanları etkileyebilmektedir. Renal ateroskleroz ve arteriyoloskleroz diyabetiklerdeki sistemik damar lezyonlarının önemli bölümünü oluşturmaktadır. Diyabetik hastalarda iyi glisemik ve sıkı kan basıncı kontrolü ile mikrovasküler komplikasyonların önlenmesi açısından önemlidir. Sunduğumuz derlemede, giderek artan oranda bir sağlık sorunu olan diyabetik nefropati hakkında genel bilgi vermek ve bu duruma dikkati çekmek amaçlanmıştır.
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