We examined the expression of minichromosome maintenance 2 (MCM2) in gastric cancer and adjacent ... more We examined the expression of minichromosome maintenance 2 (MCM2) in gastric cancer and adjacent normal tissues and estimated the possible value of MCM2 as a novel prognostic marker. Using real-time PCR, Western blotting and immunohistochemistry, we examined the expression of MCM2 in gastric carcinoma and paired normal gastric mucosa. Statistical analysis of the expression of MCM2 mRNA and protein in gastric cancer and normal tissues was performed to evaluate the relationship between MCM2 expression and clinicopathological characteristics in gastric cancer. The expression of MCM2 mRNA and protein in gastric carcinomas was significantly higher compared to that in normal gastric mucosa (P=0.04). Immunohistochemistry analysis showed that MCM2 expression was significantly up-regulated in tumor and metastastic lymph node tissues compared with the corresponding non-cancerous mucosa (P<0.05). Positive expression of MCM2 was significantly associated with patient age, T category and the presence of lymph node metastasis (P<0.05). There were no differences between MCM2 expression and gender, tumor size, tumor location, M category, International Union Against Cancer (UICC) stage, vessel invasion and tumor differentiation. Patients with negative tumor MCM2 expression displayed a better survival time than those with positive MCM2 expression (P<0.05). Survival analysis showed that positive MCM2 expression (P<0.05), T stage (P<0.05) and N stage (P<0.05) were independent prognostic factors for disease-free survival (DFS) and overall survival (OS). Our data suggest that MCM2 could serve as a novel prognostic biomarker in gastric carcinoma.
International Journal of Molecular Sciences, Jan 11, 2023
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
Glioblastoma is one of the most devastating neoplasms of the central nervous system. This study f... more Glioblastoma is one of the most devastating neoplasms of the central nervous system. This study focused on the development of serum extracellular vesicle (EV)-based glioblastoma tumor marker panels that can be used in a clinic to diagnose glioblastomas and to monitor tumor burden, progression, and regression in response to treatment. RNA sequencing studies were performed using RNA isolated from serum EVs from both patients (n = 85) and control donors (n = 31). RNA sequencing results for preoperative glioblastoma EVs compared to control EVs revealed 569 differentially expressed genes (DEGs, 2XFC, FDR < 0.05). By using these DEGs, we developed serum-EV-based biomarker panels for the following glioblastomas: wild-type IDH1 (96% sensitivity/80% specificity), MGMT promoter methylation (91% sensitivity/73% specificity), p53 gene mutation (100% sensitivity/89% specificity), and TERT promoter mutation (89% sensitivity/100% specificity). This is the first study showing that serum-EV-based...
Supplementary Table 1 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upregula... more Supplementary Table 1 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upregulating Three Oncogenic Signaling Pathways
Supplementary Figures 1-5 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upre... more Supplementary Figures 1-5 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upregulating Three Oncogenic Signaling Pathways
Studies on tumor-associated antigens in brain tumors are sparse. There is scope for enhancing our... more Studies on tumor-associated antigens in brain tumors are sparse. There is scope for enhancing our understanding of molecular pathology, in order to improve on existing forms, and discover new forms, of treatment, which could be particularly relevant to immuno-oncological strategies. To elucidate immunological differences, and to provide another level of biological information, we performed antibody profiling, based on a high-density protein array (containing 8173 human transcripts), using IgG isolated from the sera of n = 12 preoperative and n = 16 postoperative glioblastomas, n = 26 preoperative and n = 29 postoperative meningiomas, and n = 27 healthy, cancer-free controls. Differentially reactive antigens were compared to gene expression data from an alternate public GBM data set from OncoDB, and were analyzed using the Reactome pathway browser. Protein array analysis identified approximately 350–800 differentially reactive antigens, and revealed different antigen profiles in the ...
Cancer metastasis is the major cause of death from cancer (Massague and Obenauf, 2016; Steeg, 201... more Cancer metastasis is the major cause of death from cancer (Massague and Obenauf, 2016; Steeg, 2016). The extensive genetic heterogeneity and cellular plasticity of metastatic tumors set a prime barrier for the current cancer treatment protocols (Boumahdi and de Sauvage, 2020). In addition, acquired therapy resistance has become an insurmountable obstacle that abolishes the beneficial effects of numerous anti-cancer regimens (De Angelis et al., 2019; Boumahdi and de Sauvage, 2020). Here we report that deficiency of Ku leads to the exploitation of host cells in human cancer cell line models. We found that, upon conditional deletion of XRCC6 that codes for Ku70, HCT116 human colorectal cancer cells gain a parasitic lifestyle that is characterized by the continuous cycle of host cell exploitation. We also found that DAOY cells, a human medulloblastoma cell line, innately lack nuclear Ku70/Ku86 proteins and utilize the host-cell invasion/exit mechanism for maintenance of their survival, ...
Extracellular vesicles (EVs) may be used as a non-invasive screening platform to discover markers... more Extracellular vesicles (EVs) may be used as a non-invasive screening platform to discover markers associated with early diagnosis, prognosis, and treatment response. Such an approach is invaluable for diseases such as glioblastoma, for which only a few non-invasive diagnostic or prognostic markers are available. We used mass spectrometry to analyze proteomics profiles of EVs derived from four glioblastoma cell lines and human primary astrocytes (HPAs) and found that SRPX is the only protein enriched in the majority of glioblastoma EVs that was absent in the HPA-derived EVs. Then, we evaluated the relationship between SRPX protein expression and tumor grade using immunohistochemical staining (IHC) and performed colony formation and viability assays to analyze the possible function of SRPX in glioblastoma. SRPX mRNA and protein expression were associated with tumor grade. Moreover, temozolomide (TMZ)-resistant tumor tissues showed highly positive SRPX staining, compared to all other t...
La presente invention concerne une molecule d'acide nucleique isolee qui comporte une premier... more La presente invention concerne une molecule d'acide nucleique isolee qui comporte une premiere sequence d'acide nucleique 5'-ACCCTGCCGCCTGGACTCCGCCTGT-3' (SEQ ID NO: 22) ou un variant fonctionnel de celle-ci, lie fonctionnellement a une seconde sequence d'acide nucleique heterologue. La molecule d'acide nucleique isolee peut etre de l'ADN (dans un vecteur d'expression) et de l'ARN (ARNm, ARNsh ou ARNnc). L'invention concerne egalement une microvesicule comportant la molecule d'acide nucleique et une preparation de microvesicules comportant la microvesicule. L'invention concerne egalement un procede in vitro de production d'une preparation de microvesicules enrichie pour une sequence d'ARN specifique par la transfection de cellules avec la sequence d'acide nucleique, et l'isolement des microvesicules generees de celui-ci. L'invention concerne egalement des methodes d'administration d'un ARN therapeutique a un...
Departments of Neurology and Radiology, Massachusetts General Hospital, and Neuroscience Program,... more Departments of Neurology and Radiology, Massachusetts General Hospital, and Neuroscience Program, Harvard Medical School, Boston, Massachusetts 02129; Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Neuro-Oncology Research Group, Department of Neurosurgery, VU University Medical Center, Amsterdam, The Netherlands; Molecular Neuro-Oncology Laboratory and Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02129; Advanced Biomedical Computing Center, National Cancer Institute, Bethesda, Maryland 21702; Institute of Virology, University of Zurich, Zurich 8057, Switzerland; and Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115
Gene therapy involves the introduction of genes (termed transgenes) into cells to compensate for ... more Gene therapy involves the introduction of genes (termed transgenes) into cells to compensate for a deficiency or to make a beneficial protein. Gene therapy can used as a form of cancer treatment. A particularly attractive paradigm in this regard involves the selective introduction of transgenes into cancer cells that converts inactive prodrugs into active chemotherapeutic agents, thereby triggering the death of cancer cells. Since prodrugs are inactive, they tend not to cause significant side-effects and are well-tolerated by patients relative to conventional chemotherapy. Several viral and nonviral vectors have been used as delivery tools for suicide gene therapy. Extracellular vesicles (EVs) are now recognized as a promising class of nonviral delivery vectors. Here, we describe a method in which a suicide fusion gene construct is loaded into EVs derived from a non-tumorigenic cell line. Delivery of these modified EVs to glioblastoma cell lines and spheroids decreases glioblastoma cell viability, induces apoptotic cell death, and inhibits tumor growth in vivo.
Exosomes are small extracellular vesicles (sEVs), playing a crucial role in the intercellular com... more Exosomes are small extracellular vesicles (sEVs), playing a crucial role in the intercellular communication in physiological as well as pathological processes. Here, we aimed to study whether the melanoma-derived sEV-mediated communication could adapt to microenvironmental stresses. We compared B16F1 cell-derived sEVs released under normal and stress conditions, including cytostatic, heat and oxidative stress. The miRNome and proteome showed substantial differences across the sEV groups and bioinformatics analysis of the obtained data by the Ingenuity Pathway Analysis also revealed significant functional differences. The in silico predicted functional alterations of sEVs were validated by in vitro assays. For instance, melanoma-derived sEVs elicited by oxidative stress increased Ki-67 expression of mesenchymal stem cells (MSCs); cytostatic stress-resulted sEVs facilitated melanoma cell migration; all sEV groups supported microtissue generation of MSC-B16F1 co-cultures in a 3D tumour...
Meningiomas are primary central nervous system (CNS) tumors that originate from the arachnoid cel... more Meningiomas are primary central nervous system (CNS) tumors that originate from the arachnoid cells of the meninges. Recurrence occurs in higher grade meningiomas and a small subset of Grade I meningiomas with benign histology. Currently, there are no established circulating tumor markers which can be used for diagnostic and prognostic purposes in a non-invasive way for meningiomas. Here, we aimed to identify potential biomarkers of meningioma in patient sera. For this purpose, we collected preoperative (n = 30) serum samples from the meningioma patients classified as Grade I (n = 23), Grade II (n = 4), or Grade III (n = 3). We used a high-throughput, multiplex immunoassay cancer panel comprising of 92 cancer-related protein biomarkers to explore the serum protein profiles of meningioma patients. We detected 14 differentially expressed proteins in the sera of the Grade I meningioma patients in comparison to the age-and gender-matched control subjects (n = 12). Compared to the control group, Grade I meningioma patients showed increased serum levels of amphiregulin (AREG), CCL24, CD69, prolactin, EGF, HB-EGF, caspase-3, and decreased levels of VEGFD, TGF-α, E-Selectin, BAFF, IL-12, CCL9, and GH. For validation studies, we utilized an independent set of meningioma tumor tissue samples (Grade I, n = 20; Grade II, n = 10; Grade III, n = 6), and found that the expressions of amphiregulin and Caspase3 are significantly increased in all grades of meningiomas either at the transcriptional or protein level, respectively. In contrast, the gene expression of VEGF-D was significantly lower in Grade I meningioma tissue samples. Taken together, our study identifies a meningioma-specific protein signature in blood circulation of meningioma patients and highlights the importance of equilibrium between tumor-promoting factors and anti-tumor immunity.
We examined the expression of minichromosome maintenance 2 (MCM2) in gastric cancer and adjacent ... more We examined the expression of minichromosome maintenance 2 (MCM2) in gastric cancer and adjacent normal tissues and estimated the possible value of MCM2 as a novel prognostic marker. Using real-time PCR, Western blotting and immunohistochemistry, we examined the expression of MCM2 in gastric carcinoma and paired normal gastric mucosa. Statistical analysis of the expression of MCM2 mRNA and protein in gastric cancer and normal tissues was performed to evaluate the relationship between MCM2 expression and clinicopathological characteristics in gastric cancer. The expression of MCM2 mRNA and protein in gastric carcinomas was significantly higher compared to that in normal gastric mucosa (P=0.04). Immunohistochemistry analysis showed that MCM2 expression was significantly up-regulated in tumor and metastastic lymph node tissues compared with the corresponding non-cancerous mucosa (P<0.05). Positive expression of MCM2 was significantly associated with patient age, T category and the presence of lymph node metastasis (P<0.05). There were no differences between MCM2 expression and gender, tumor size, tumor location, M category, International Union Against Cancer (UICC) stage, vessel invasion and tumor differentiation. Patients with negative tumor MCM2 expression displayed a better survival time than those with positive MCM2 expression (P<0.05). Survival analysis showed that positive MCM2 expression (P<0.05), T stage (P<0.05) and N stage (P<0.05) were independent prognostic factors for disease-free survival (DFS) and overall survival (OS). Our data suggest that MCM2 could serve as a novel prognostic biomarker in gastric carcinoma.
International Journal of Molecular Sciences, Jan 11, 2023
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
Glioblastoma is one of the most devastating neoplasms of the central nervous system. This study f... more Glioblastoma is one of the most devastating neoplasms of the central nervous system. This study focused on the development of serum extracellular vesicle (EV)-based glioblastoma tumor marker panels that can be used in a clinic to diagnose glioblastomas and to monitor tumor burden, progression, and regression in response to treatment. RNA sequencing studies were performed using RNA isolated from serum EVs from both patients (n = 85) and control donors (n = 31). RNA sequencing results for preoperative glioblastoma EVs compared to control EVs revealed 569 differentially expressed genes (DEGs, 2XFC, FDR < 0.05). By using these DEGs, we developed serum-EV-based biomarker panels for the following glioblastomas: wild-type IDH1 (96% sensitivity/80% specificity), MGMT promoter methylation (91% sensitivity/73% specificity), p53 gene mutation (100% sensitivity/89% specificity), and TERT promoter mutation (89% sensitivity/100% specificity). This is the first study showing that serum-EV-based...
Supplementary Table 1 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upregula... more Supplementary Table 1 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upregulating Three Oncogenic Signaling Pathways
Supplementary Figures 1-5 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upre... more Supplementary Figures 1-5 from miRNA-7 Attenuation in Schwannoma Tumors Stimulates Growth by Upregulating Three Oncogenic Signaling Pathways
Studies on tumor-associated antigens in brain tumors are sparse. There is scope for enhancing our... more Studies on tumor-associated antigens in brain tumors are sparse. There is scope for enhancing our understanding of molecular pathology, in order to improve on existing forms, and discover new forms, of treatment, which could be particularly relevant to immuno-oncological strategies. To elucidate immunological differences, and to provide another level of biological information, we performed antibody profiling, based on a high-density protein array (containing 8173 human transcripts), using IgG isolated from the sera of n = 12 preoperative and n = 16 postoperative glioblastomas, n = 26 preoperative and n = 29 postoperative meningiomas, and n = 27 healthy, cancer-free controls. Differentially reactive antigens were compared to gene expression data from an alternate public GBM data set from OncoDB, and were analyzed using the Reactome pathway browser. Protein array analysis identified approximately 350–800 differentially reactive antigens, and revealed different antigen profiles in the ...
Cancer metastasis is the major cause of death from cancer (Massague and Obenauf, 2016; Steeg, 201... more Cancer metastasis is the major cause of death from cancer (Massague and Obenauf, 2016; Steeg, 2016). The extensive genetic heterogeneity and cellular plasticity of metastatic tumors set a prime barrier for the current cancer treatment protocols (Boumahdi and de Sauvage, 2020). In addition, acquired therapy resistance has become an insurmountable obstacle that abolishes the beneficial effects of numerous anti-cancer regimens (De Angelis et al., 2019; Boumahdi and de Sauvage, 2020). Here we report that deficiency of Ku leads to the exploitation of host cells in human cancer cell line models. We found that, upon conditional deletion of XRCC6 that codes for Ku70, HCT116 human colorectal cancer cells gain a parasitic lifestyle that is characterized by the continuous cycle of host cell exploitation. We also found that DAOY cells, a human medulloblastoma cell line, innately lack nuclear Ku70/Ku86 proteins and utilize the host-cell invasion/exit mechanism for maintenance of their survival, ...
Extracellular vesicles (EVs) may be used as a non-invasive screening platform to discover markers... more Extracellular vesicles (EVs) may be used as a non-invasive screening platform to discover markers associated with early diagnosis, prognosis, and treatment response. Such an approach is invaluable for diseases such as glioblastoma, for which only a few non-invasive diagnostic or prognostic markers are available. We used mass spectrometry to analyze proteomics profiles of EVs derived from four glioblastoma cell lines and human primary astrocytes (HPAs) and found that SRPX is the only protein enriched in the majority of glioblastoma EVs that was absent in the HPA-derived EVs. Then, we evaluated the relationship between SRPX protein expression and tumor grade using immunohistochemical staining (IHC) and performed colony formation and viability assays to analyze the possible function of SRPX in glioblastoma. SRPX mRNA and protein expression were associated with tumor grade. Moreover, temozolomide (TMZ)-resistant tumor tissues showed highly positive SRPX staining, compared to all other t...
La presente invention concerne une molecule d'acide nucleique isolee qui comporte une premier... more La presente invention concerne une molecule d'acide nucleique isolee qui comporte une premiere sequence d'acide nucleique 5'-ACCCTGCCGCCTGGACTCCGCCTGT-3' (SEQ ID NO: 22) ou un variant fonctionnel de celle-ci, lie fonctionnellement a une seconde sequence d'acide nucleique heterologue. La molecule d'acide nucleique isolee peut etre de l'ADN (dans un vecteur d'expression) et de l'ARN (ARNm, ARNsh ou ARNnc). L'invention concerne egalement une microvesicule comportant la molecule d'acide nucleique et une preparation de microvesicules comportant la microvesicule. L'invention concerne egalement un procede in vitro de production d'une preparation de microvesicules enrichie pour une sequence d'ARN specifique par la transfection de cellules avec la sequence d'acide nucleique, et l'isolement des microvesicules generees de celui-ci. L'invention concerne egalement des methodes d'administration d'un ARN therapeutique a un...
Departments of Neurology and Radiology, Massachusetts General Hospital, and Neuroscience Program,... more Departments of Neurology and Radiology, Massachusetts General Hospital, and Neuroscience Program, Harvard Medical School, Boston, Massachusetts 02129; Molecular Neurogenetics Unit, Center for Human Genetic Research, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02114; Neuro-Oncology Research Group, Department of Neurosurgery, VU University Medical Center, Amsterdam, The Netherlands; Molecular Neuro-Oncology Laboratory and Department of Pathology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts 02129; Advanced Biomedical Computing Center, National Cancer Institute, Bethesda, Maryland 21702; Institute of Virology, University of Zurich, Zurich 8057, Switzerland; and Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, Massachusetts 02115
Gene therapy involves the introduction of genes (termed transgenes) into cells to compensate for ... more Gene therapy involves the introduction of genes (termed transgenes) into cells to compensate for a deficiency or to make a beneficial protein. Gene therapy can used as a form of cancer treatment. A particularly attractive paradigm in this regard involves the selective introduction of transgenes into cancer cells that converts inactive prodrugs into active chemotherapeutic agents, thereby triggering the death of cancer cells. Since prodrugs are inactive, they tend not to cause significant side-effects and are well-tolerated by patients relative to conventional chemotherapy. Several viral and nonviral vectors have been used as delivery tools for suicide gene therapy. Extracellular vesicles (EVs) are now recognized as a promising class of nonviral delivery vectors. Here, we describe a method in which a suicide fusion gene construct is loaded into EVs derived from a non-tumorigenic cell line. Delivery of these modified EVs to glioblastoma cell lines and spheroids decreases glioblastoma cell viability, induces apoptotic cell death, and inhibits tumor growth in vivo.
Exosomes are small extracellular vesicles (sEVs), playing a crucial role in the intercellular com... more Exosomes are small extracellular vesicles (sEVs), playing a crucial role in the intercellular communication in physiological as well as pathological processes. Here, we aimed to study whether the melanoma-derived sEV-mediated communication could adapt to microenvironmental stresses. We compared B16F1 cell-derived sEVs released under normal and stress conditions, including cytostatic, heat and oxidative stress. The miRNome and proteome showed substantial differences across the sEV groups and bioinformatics analysis of the obtained data by the Ingenuity Pathway Analysis also revealed significant functional differences. The in silico predicted functional alterations of sEVs were validated by in vitro assays. For instance, melanoma-derived sEVs elicited by oxidative stress increased Ki-67 expression of mesenchymal stem cells (MSCs); cytostatic stress-resulted sEVs facilitated melanoma cell migration; all sEV groups supported microtissue generation of MSC-B16F1 co-cultures in a 3D tumour...
Meningiomas are primary central nervous system (CNS) tumors that originate from the arachnoid cel... more Meningiomas are primary central nervous system (CNS) tumors that originate from the arachnoid cells of the meninges. Recurrence occurs in higher grade meningiomas and a small subset of Grade I meningiomas with benign histology. Currently, there are no established circulating tumor markers which can be used for diagnostic and prognostic purposes in a non-invasive way for meningiomas. Here, we aimed to identify potential biomarkers of meningioma in patient sera. For this purpose, we collected preoperative (n = 30) serum samples from the meningioma patients classified as Grade I (n = 23), Grade II (n = 4), or Grade III (n = 3). We used a high-throughput, multiplex immunoassay cancer panel comprising of 92 cancer-related protein biomarkers to explore the serum protein profiles of meningioma patients. We detected 14 differentially expressed proteins in the sera of the Grade I meningioma patients in comparison to the age-and gender-matched control subjects (n = 12). Compared to the control group, Grade I meningioma patients showed increased serum levels of amphiregulin (AREG), CCL24, CD69, prolactin, EGF, HB-EGF, caspase-3, and decreased levels of VEGFD, TGF-α, E-Selectin, BAFF, IL-12, CCL9, and GH. For validation studies, we utilized an independent set of meningioma tumor tissue samples (Grade I, n = 20; Grade II, n = 10; Grade III, n = 6), and found that the expressions of amphiregulin and Caspase3 are significantly increased in all grades of meningiomas either at the transcriptional or protein level, respectively. In contrast, the gene expression of VEGF-D was significantly lower in Grade I meningioma tissue samples. Taken together, our study identifies a meningioma-specific protein signature in blood circulation of meningioma patients and highlights the importance of equilibrium between tumor-promoting factors and anti-tumor immunity.
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