Displaying publications 61 - 80 of 656 in total

Abstract:
Sort:
  1. Lung RW, Hau PM, Yu KH, Yip KY, Tong JH, Chak WP, et al.
    J Pathol, 2018 Apr;244(4):394-407.
    PMID: 29230817 DOI: 10.1002/path.5018
    Nasopharyngeal carcinoma (NPC) is a highly invasive epithelial malignancy that is prevalent in southern China and Southeast Asia. It is consistently associated with latent Epstein-Barr virus (EBV) infection. In NPC, miR-BARTs, the EBV-encoded miRNAs derived from BamH1-A rightward transcripts, are abundantly expressed and contribute to cancer development by targeting various cellular and viral genes. In this study, we establish a comprehensive transcriptional profile of EBV-encoded miRNAs in a panel of NPC patient-derived xenografts and an EBV-positive NPC cell line by small RNA sequencing. Among the 40 miR-BARTs, predominant expression of 22 miRNAs was consistently detected in these tumors. Among the abundantly expressed EBV-miRNAs, BART5-5p, BART7-3p, BART9-3p, and BART14-3p could negatively regulate the expression of a key DNA double-strand break (DSB) repair gene, ataxia telangiectasia mutated (ATM), by binding to multiple sites on its 3'-UTR. Notably, the expression of these four miR-BARTs represented more than 10% of all EBV-encoded miRNAs in tumor cells, while downregulation of ATM expression was commonly detected in all of our tested sequenced samples. In addition, downregulation of ATM was also observed in primary NPC tissues in both qRT-PCR (16 NP and 45 NPC cases) and immunohistochemical staining (35 NP and 46 NPC cases) analysis. Modulation of ATM expression by BART5-5p, BART7-3p, BART9-3p, and BART14-3p was demonstrated in the transient transfection assays. These findings suggest that EBV uses miRNA machinery as a key mechanism to control the ATM signaling pathway in NPC cells. By suppressing these endogenous miR-BARTs in EBV-positive NPC cells, we further demonstrated the novel function of miR-BARTs in inhibiting Zta-induced lytic reactivation. These findings imply that the four viral miRNAs work co-operatively to modulate ATM activity in response to DNA damage and to maintain viral latency, contributing to the tumorigenesis of NPC. © 2017 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.
    Matched MeSH terms: Nasopharyngeal Neoplasms/genetics*
  2. Abd-Aziz N, Stanbridge EJ, Shafee N
    J Gen Virol, 2016 Dec;97(12):3174-3182.
    PMID: 27902314 DOI: 10.1099/jgv.0.000623
    Newcastle disease virus (NDV) is a candidate agent for oncolytic virotherapy. Despite its potential, the exact mechanism of its oncolysis is still not known. Recently, we reported that NDV exhibited an increased oncolytic activity in hypoxic cancer cells. These types of cells negatively affect therapeutic outcome by overexpressing pro-survival genes under the control of the hypoxia-inducible factor (HIF). HIF-1 is a heterodimeric transcriptional factor consisting of a regulated α (HIF-1α) and a constitutive β subunit (HIF-1β). To investigate the effects of NDV infection on HIF-1α in cancer cells, the osteosarcoma (Saos-2), breast carcinoma (MCF-7), colon carcinoma (HCT116) and fibrosarcoma (HT1080) cell lines were used in the present study. Data obtained showed that a velogenic NDV infection diminished hypoxia-induced HIF-1α accumulation, leading to a decreased activation of its downstream target gene, carbonic anhydrase 9. This NDV-induced downregulation of HIF-1α occurred post-translationally and was partially abrogated by proteasomal inhibition. The process appeared to be independent of the tumour suppressor protein p53. These data revealed a correlation between NDV infection and HIF-1α downregulation, which highlights NDV as a promising agent to eliminate hypoxic cancer cells.
    Matched MeSH terms: Neoplasms/genetics
  3. Leow MKS, Dogra S, Ge X, Chuah KL, Liew H, Loke KSH, et al.
    J Clin Endocrinol Metab, 2021 04 23;106(5):e2299-e2308.
    PMID: 33462615 DOI: 10.1210/clinem/dgaa964
    CONTEXT: Literature suggests that oncogenic osteomalacia is usually caused by a benign mesenchymal tumor secreting fibroblast growth factor subtype-23 (FGF-23), but the involvement of other phosphatonins has only been scarcely reported. We have previously published a seemingly typical case of oncogenic osteomalacia. Following curative neoplasm resection, we now report unique molecular characteristics and biology of this tumor.

    CASE DESCRIPTION: A 25-year-old man had been diagnosed with severe oncogenic osteomalacia that gradually crippled him over 6 years. 68Ga-DOTA-TATE positron emission tomography/computed tomography scan localized the culprit tumor to his left sole, which on resection revealed a deep fibrous histiocytoma displaying a proliferation of spindle cells with storiform pattern associated with multinucleated giant cells resembling osteoclasts. Circulating FGF-23, which was elevated more than 2-fold, declined to undetectable levels 24 h after surgery. Microarray analysis revealed increased tumor gene expression of the phosphatonins FGF-23, matrix extracellular phosphoglycoprotein (MEPE) and secreted frizzled-related protein subtype 4, with elevated levels of all 3 proteins confirmed through immunoblot analysis. Differential expression of genes involved in bone formation and bone mineralization were further identified. The patient made an astonishing recovery from being wheelchair bound to fully self-ambulant 2 months postoperatively.

    CONCLUSION: This report describes oncogenic osteomalacia due to a deep fibrous histiocytoma, which coincidentally has been found to induce profound muscle weakness via the overexpression of 3 phosphatonins, which resolved fully upon radical resection of the tumor. Additionally, genes involved in bone formation and bone remodeling contribute to the molecular signature of oncogenic osteomalacia.

    Matched MeSH terms: Soft Tissue Neoplasms/genetics
  4. Kaur G, Masoud A, Raihan N, Radzi M, Khamizar W, Kam LS
    Indian J Med Res, 2011 Aug;134:186-92.
    PMID: 21911971
    DNA mismatch repair gene (MMR) abnormalities are seen in 95 per cent of hereditary nonpolyposis colorectal cancer (HNPCC) and 10-15 per cent of sporadic colorectal cancers. There are no data on MMR abnormalities in Malaysian colorectal cancer patients. This study was aimed to determine the frequency of abnormal MMR gene protein expression in colorectal carcinoma in Northern Peninsular Malaysia using immunohistochemistry.
    Matched MeSH terms: Colorectal Neoplasms/genetics*
  5. Al Joudi FS
    Indian J Med Res, 2014 May;139(5):675-85.
    PMID: 25027076
    Human mammaglobin is a member of the uteroglobin proteins family that has recently been tested as a specific marker for breast cancer. While low levels may be seen in normal breast tissue, expression is increased dramatically in breast cancer and is correlated with higher grade. Detection in blood and body fluids is also correlated with cancer metastasis, and its levels with prognosis. This promises to be a useful screen for early detection of breast cancer, especially in high risk individuals. Mammoglobin has also been used for immunotherapeutic targeting of breast cancer cells. However, there are some controversies regarding its diagnostic efficacy and prognostic value, which warrant further study.
    Matched MeSH terms: Breast Neoplasms/genetics
  6. Ramzi NH, Chahil JK, Lye SH, Munretnam K, Sahadevappa KI, Velapasamy S, et al.
    Indian J Med Res, 2014 Jun;139(6):873-82.
    PMID: 25109722
    Colorectal cancer (CRC) is second only to breast cancer as the leading cause of cancer-related deaths in Malaysia. In the Asia-Pacific area, it is the highest emerging gastrointestinal cancer. The aim of this study was to identify single nucleotide polymorphisms (SNPs) and environmental factors associated with CRC risk in Malaysia from a panel of cancer associated SNPs.
    Matched MeSH terms: Colorectal Neoplasms/genetics*
  7. Seow P, Wong JHD, Ahmad-Annuar A, Mahajan A, Abdullah NA, Ramli N
    Br J Radiol, 2018 Dec;91(1092):20170930.
    PMID: 29902076 DOI: 10.1259/bjr.20170930
    OBJECTIVE:: The diversity of tumour characteristics among glioma patients, even within same tumour grade, is a big challenge for disease outcome prediction. A possible approach for improved radiological imaging could come from combining information obtained at the molecular level. This review assembles recent evidence highlighting the value of using radiogenomic biomarkers to infer the underlying biology of gliomas and its correlation with imaging features.

    METHODS:: A literature search was done for articles published between 2002 and 2017 on Medline electronic databases. Of 249 titles identified, 38 fulfilled the inclusion criteria, with 14 articles related to quantifiable imaging parameters (heterogeneity, vascularity, diffusion, cell density, infiltrations, perfusion, and metabolite changes) and 24 articles relevant to molecular biomarkers linked to imaging.

    RESULTS:: Genes found to correlate with various imaging phenotypes were EGFR, MGMT, IDH1, VEGF, PDGF, TP53, and Ki-67. EGFR is the most studied gene related to imaging characteristics in the studies reviewed (41.7%), followed by MGMT (20.8%) and IDH1 (16.7%). A summary of the relationship amongst glioma morphology, gene expressions, imaging characteristics, prognosis and therapeutic response are presented.

    CONCLUSION:: The use of radiogenomics can provide insights to understanding tumour biology and the underlying molecular pathways. Certain MRI characteristics that show strong correlations with EGFR, MGMT and IDH1 could be used as imaging biomarkers. Knowing the pathways involved in tumour progression and their associated imaging patterns may assist in diagnosis, prognosis and treatment management, while facilitating personalised medicine.

    ADVANCES IN KNOWLEDGE:: Radiogenomics can offer clinicians better insight into diagnosis, prognosis, and prediction of therapeutic responses of glioma.

    Matched MeSH terms: Brain Neoplasms/genetics
  8. Teh LK, Mohamed NI, Salleh MZ, Rohaizak M, Shahrun NS, Saladina JJ, et al.
    AAPS J, 2012 Mar;14(1):52-9.
    PMID: 22183189 DOI: 10.1208/s12248-011-9313-6
    CYP2D6 plays a major role in the metabolism of tamoxifen, and polymorphism of P-glycoprotein has been associated with resistance of many drug therapies. This study investigates the clinical impact of genetic variants of CYP2D6 and ABCB1 in breast cancer patients treated with tamoxifen. Blood samples from 95 breast cancer patients treated with tamoxifen were collected and genotyped for CYP2D6 and ABCB1 variants using allele-specific PCR method. Recurrence risks were calculated using Kaplan-Meier analysis and compared using the log-rank test. Patients carrying CYP2D6*10/*10 and heterozygous null allele (IM) showed higher risks of developing recurrence and metastasis (OR 13.14; 95% CI 1.57-109.94; P = 0.004) than patients with CYP2D6*1/*1 and *1/*10 genotypes. Patients with homozygous CC genotypes of ABCB1 C3435T showed a shorter time to recurrence. Patients who were CYP2D6 IM and homozygous CC genotype of C3435T have statistically significant higher risks of recurrence (P = 0.002). Similarly, median time to recurrence in these patients was only 12 months (95% CI = 0.79-23.2) compared to those without this combination which was 48 months (95% CI = 14.7-81.2). Patients with CYP2D6 IM and homozygous CC genotype of ABCB1 C3435T have shorter times to recurrence. The results confirmed the findings of previous studies and support FDA recommendation to perform pre-genotyping in patients before the choice of therapy is determined in breast cancer patients.
    Matched MeSH terms: Breast Neoplasms/genetics
  9. Md Fuzi AA, Omar SZ, Mohamed Z, Mat Adenan NA, Mokhtar NM
    Taiwan J Obstet Gynecol, 2018 Apr;57(2):217-226.
    PMID: 29673664 DOI: 10.1016/j.tjog.2018.02.009
    OBJECTIVE: To validate the gene expression profile obtained from the previous microarray analysis and to further study the biological functions of these genes in endometrial cancer. From our previous study, we identified 621 differentially expressed genes in laser-captured microdissected endometrioid endometrial cancer as compared to normal endometrial cells. Among these genes, 146 were significantly up-regulated in endometrial cancer.

    MATERIALS AND METHODS: A total of 20 genes were selected from the list of up-regulated genes for the validation assay. The qPCR confirmed that 19 out of the 20 genes were up-regulated in endometrial cancer compared with normal endometrium. RNA interference (RNAi) was used to knockdown the expression of the upregulated genes in ECC-1 and HEC-1A endometrial cancer cell lines and its effect on proliferation, migration and invasion were examined.

    RESULTS: Knockdown of MIF, SOD2, HIF1A and SLC7A5 by RNAi significantly decreased the proliferation of ECC-1 cells (p < 0.05). Our results also showed that the knockdown of MIF, SOD2 and SLC7A5 by RNAi significantly decreased the proliferation and migration abilities of HEC-1A cells (p < 0.05). Moreover, the knockdown of SLC38A1 and HIF1A by RNAi resulted in a significant decrease in the proliferation of HEC1A cells (p < 0.05).

    CONCLUSION: We have identified the biological roles of SLC38A1, MIF, SOD2, HIF1A and SLC7A5 in endometrial cancer, which opens up the possibility of using the RNAi silencing approach to design therapeutic strategies for treatment of endometrial cancer.

    Matched MeSH terms: Endometrial Neoplasms/genetics*
  10. Yin Lee JP, Thomas AJ, Lum SK, Shamsudin NH, Hii LW, Mai CW, et al.
    Surg Oncol, 2021 Jun;37:101536.
    PMID: 33677364 DOI: 10.1016/j.suronc.2021.101536
    INTRODUCTION: Fibroadenomas of the breast present as two phenotypic variants. The usual variety is 5 cm or less in diameter and there is another large variant called giant fibroadenoma which is greater than 5 cm in diameter. Despite of its large size, it is not malignant. The aim of our study is to determine whether this large variant is different from the usual fibroadenoma in terms of its biological pathways and biomarkers.

    METHODS: mRNA was extracted from 44 fibroadenomas and 36 giant fibroadenomas, and transcriptomic profiling was performed to identify up- and down-regulated genes in the giant fibroadenomas as compared to the fibroadenomas.

    RESULTS: A total of 40 genes were significantly up-regulated and 18 genes were significantly down-regulated in the giant fibroadenomas as compared to the fibroadenomas of the breast. The top 5 up-regulated genes were FN1, IL3, CDC6, FGF8 and BMP8A. The top 5 down-regulated genes were TNR, CDKN2A, COL5A1, THBS4 and BMPR1B. The differentially expressed genes (DEGs) were found to be associated with 5 major canonical pathways involved in cell growth (PI3K-AKT, cell cycle regulation, WNT, and RAS signalling) and immune response (JAK-STAT signalling). Further analyses using 3 supervised learning algorithms identified an 8-gene signature (FN1, CDC6, IL23A, CCNA1, MCM4, FLT1, FGF22 and COL5A1) that could distinguish giant fibroadenomas from fibroadenomas with high predictive accuracy.

    CONCLUSION: Our findings demonstrated that the giant fibroadenomas are biologically distinct to fibroadenomas of the breast with overexpression of genes involved in the regulation of cell growth and immune response.

    Matched MeSH terms: Breast Neoplasms/genetics*
  11. Zulhabri O, Rahman J, Ismail S, Isa MR, Wan Zurinah WN
    Singapore Med J, 2012 Jan;53(1):26-31.
    PMID: 22252179
    K-ras gene mutations in codons 12 and 13 are one of the earliest events in colon carcinogenesis.
    Matched MeSH terms: Colorectal Neoplasms/genetics*
  12. Balraj P, Khoo AS, Volpi L, Tan JA, Nair S, Abdullah H
    Singapore Med J, 2002 Apr;43(4):194-7.
    PMID: 12188064
    Thirty patients with early onset breast cancer or familial breast cancer from Malaysia were analysed for germline mutation in the early onset breast cancer I gene (BRCA1). Direct sequencing of the entire coding region of BRCA1 identified a frameshift mutation, c.5447-5448insC (insC5447) (codon 1776 of exon 21) in a patient aged 32 of the Malay ethnic origin, who had no family history of breast and/or ovarian cancer. Eight polymorphisms (2201C > T, 2430T > C, P871L, E1038G, K1183R, 4427T > C, S1613G and IVS8-57delT) were identified in the samples tested.
    Matched MeSH terms: Breast Neoplasms/genetics*
  13. Lee LK, Tan EL, Gopala K, Sam CK
    Singapore Med J, 2007 Jul;48(7):632-4.
    PMID: 17609824
    Nasopharyngeal carcinoma (NPC) is the second most common cancer among Malaysian Chinese males. We determined the frequencies of 17 human leukocyte antigens (HLA), HLA-A and HLA-B, alleles in 88 Malaysian Chinese with NPC.
    Matched MeSH terms: Nasopharyngeal Neoplasms/genetics*
  14. Chai AWY, Lim KP, Cheong SC
    Semin Cancer Biol, 2020 04;61:71-83.
    PMID: 31542510 DOI: 10.1016/j.semcancer.2019.09.011
    Oral squamous cell carcinomas (OSCC) are a heterogeneous group of cancers arising from the mucosal lining of the oral cavity. A majority of these cancers are associated with lifestyle risk habits including smoking, excessive alcohol consumption and betel quid chewing. Cetuximab, targeting the epidermal growth factor receptor was approved for the treatment of OSCC in 2006, and remains the only molecular targeted therapy available for OSCC. Here, we reviewed the current findings from genomic analyses of OSCC and discuss how these studies inform on the biological mechanisms underlying OSCC. Exome sequencing revealed that the significantly mutated genes are mainly tumour suppressors. Mutations in FAT1, CASP8, CDKN2A, and NOTCH1 are more frequently found in OSCC when compared to non-OSCC head and neck cancers and other squamous cell carcinomas, and HRAS and PIK3CA are the only significantly mutated oncogenes. The distribution of these mutations also differs in populations with distinct risk habits. Gene expression-based molecular classification showed that OSCC can be divided into distinct subtypes and these have a preferential response to different types of therapies, suggesting that these classifications could have clinical implications. More recently, with the approval of checkpoint inhibitors for the treatment of cancers including OSCC, genomics studies also dissected the genetic signatures of the immune compartment to delineate immune-active and -exhausted subtypes that could inform on the immune status of OSCC patients and guide the development of novel therapies to improve response to immunotherapy. Taken together, genomics studies are informing on the biology of both the epithelial and stromal compartments underlying OSCC development, and we discuss the opportunities and challenges in using these to derive clinical benefit for OSCC patients.
    Matched MeSH terms: Mouth Neoplasms/genetics*
  15. Yong ZW, Zaini ZM, Kallarakkal TG, Karen-Ng LP, Rahman ZA, Ismail SM, et al.
    Sci Rep, 2014;4:6073.
    PMID: 25123227 DOI: 10.1038/srep06073
    The clinical relevance of DNA copy number alterations in chromosome 8 were investigated in oral cancers. The copy numbers of 30 selected genes in 33 OSCC patients were detected using the multiplex ligation-dependent probe amplification (MLPA) technique. Amplifications of the EIF3E gene were found in 27.3% of the patients, MYC in 18.2%, RECQL4 in 15.2% and MYBL1 in 12.1% of patients. The most frequent gene losses found were the GATA4 gene (24.2%), FGFR1 gene (24.2%), MSRA (21.2) and CSGALNACT1 (12.1%). The co-amplification of EIF3E and RECQL4 was found in 9% of patients and showed significant association with alcohol drinkers. There was a significant association between the amplification of EIF3E gene with non-betel quid chewers and the negative lymph node status. EIF3E amplifications did not show prognostic significance on survival. Our results suggest that EIF3E may have a role in the carcinogenesis of OSCC in non-betel quid chewers.
    Matched MeSH terms: Mouth Neoplasms/genetics*
  16. Gao Y, Zhang W, Liu C, Li G
    Sci Rep, 2019 12 11;9(1):18844.
    PMID: 31827114 DOI: 10.1038/s41598-019-54289-6
    Resistance to tamoxifen is a major clinical challenge. Research in recent years has identified epigenetic changes as mediated by dysregulated miRNAs that can possibly play a role in resistance to tamoxifen in breast cancer patients expressing estrogen receptor (ER). We report here elevated levels of EMT markers (vimentin and ZEB1/2) and reduced levels of EMT-regulating miR-200 (miR-200b and miR-200c) in ER-positive breast cancer cells, MCF-7, that were resistant to tamoxifen, in contrast with the naïve parental MCF-7 cells that were sensitive to tamoxifen. Further, we established regulation of c-MYB by miR-200 in our experimental model. C-MYB was up-regulated in tamoxifen resistant cells and its silencing significantly decreased resistance to tamoxifen and the EMT markers. Forced over-expression of miR-200b/c reduced c-MYB whereas reduced expression of miR-200b/c resulted in increased c-MYB We further confirmed the results in other ER-positive breast cancer cells T47D cells where forced over-expression of c-MYB resulted in induction of EMT and significantly increased resistance to tamoxifen. Thus, we identify a novel mechanism of tamoxifen resistance in breast tumor microenvironment that involves miR-200-MYB signaling.
    Matched MeSH terms: Breast Neoplasms/genetics
  17. Ramanathan S, Gopinath SCB, Arshad MKM, Poopalan P, Anbu P, Lakshmipriya T, et al.
    Sci Rep, 2019 11 19;9(1):17013.
    PMID: 31745155 DOI: 10.1038/s41598-019-53573-9
    Lung cancer is one of the most serious threats to human where 85% of lethal death caused by non-small cell lung cancer (NSCLC) induced by epidermal growth factor receptor (EGFR) mutation. The present research focuses in the development of efficient and effortless EGFR mutant detection strategy through high-performance and sensitive genosensor. The current amplified through 250 µm sized fingers between 100 µm aluminium electrodes indicates the voltammetry signal generated by means of the mutant DNA sequence hybridization. To enhance the DNA immobilization and hybridization, ∼25 nm sized aluminosilicate nanocomposite synthesized from the disposed joss fly ash was deposited on the gaps between aluminium electrodes. The probe, mutant (complementary), and wild (single-base pair mismatch) targets were designed precisely from the genomic sequences denote the detection of EGFR mutation. Fourier-transform Infrared Spectroscopy analysis was performed at every step of surface functionalization evidences the relevant chemical bonding of biomolecules on the genosensor as duplex DNA with peak response at 1150 cm-1 to 1650 cm-1. Genosensor depicts a sensitive EGFR mutation as it is able to detect apparently at 100 aM mutant against 1 µM DNA probe. The insignificant voltammetry signal generated with wild type strand emphasizes the specificity of genosensor in the detection of single base pair mismatch. The inefficiency of genosensor in detecting EGFR mutation in the absence of aluminosilicate nanocomposite implies the insensitivity of genosensing DNA hybridization and accentuates the significance of aluminosilicate. Based on the slope of the calibration curve, the attained sensitivity of aluminosilicate modified genosensor was 3.02E-4 A M-1. The detection limit of genosensor computed based on 3σ calculation, relative to the change of current proportional to the logarithm of mutant concentration is at 100 aM.
    Matched MeSH terms: Lung Neoplasms/genetics*
  18. Ramesh T, Foo KL, R H, Sam AJ, Solayappan M
    Sci Rep, 2019 11 19;9(1):17039.
    PMID: 31745139 DOI: 10.1038/s41598-019-53476-9
    Detection of host integrated viral oncogenes are critical for early and point-of-care molecular diagnostics of virus-induced carcinoma. However, available diagnostic approaches are incapable of combining both cost-efficient medical diagnosis and high analytical performances. To circumvent this, we have developed an improved IDE-based nanobiosensor for biorecognition of HPV-16 infected cervical cancer cells through electrochemical impedance spectroscopy. The system is fabricated by coating gold (Au) doped zinc oxide (ZnO) nanorods interfaced with HPV-16 viral DNA bioreceptors on top of the Interdigitated Electrode (IDE) chips surface. Due to the concurrently improved sensitivity and biocompatibility of the designed nanohybrid film, Au decorated ZnO-Nanorod biosensors demonstrate exceptional detection of HPV-16 E6 oncogene, the cancer biomarker for HPV infected cervical cancers. This sensor displayed high levels of sensitivity by detecting as low as 1fM of viral E6 gene target. The sensor also exhibited a stable functional life span of more than 5 weeks, good reproducibility and high discriminatory properties against HPV-16. Sensor current responses are obtained from cultured cervical cancer cells which are close to clinical cancer samples. Hence, the developed sensor is an adaptable tool with high potential for clinical diagnosis especially useful for economically challenged countries/regions.
    Matched MeSH terms: Uterine Cervical Neoplasms/genetics*
  19. Zaini MN, Patel SA, Syafruddin SE, Rodrigues P, Vanharanta S
    Sci Rep, 2018 08 13;8(1):12063.
    PMID: 30104738 DOI: 10.1038/s41598-018-30499-2
    Tissue-specific transcriptional programs control most biological phenotypes, including disease states such as cancer. However, the molecular details underlying transcriptional specificity is largely unknown, hindering the development of therapeutic approaches. Here, we describe novel experimental reporter systems that allow interrogation of the endogenous expression of HIF2A, a critical driver of renal oncogenesis. Using a focused CRISPR-Cas9 library targeting chromatin regulators, we provide evidence that these reporter systems are compatible with high-throughput screening. Our data also suggests redundancy in the control of cancer type-specific transcriptional traits. Reporter systems such as those described here could facilitate large-scale mechanistic dissection of transcriptional programmes underlying cancer phenotypes, thus paving the way for novel therapeutic approaches.
    Matched MeSH terms: Kidney Neoplasms/genetics
  20. Lee HM, Sia APE, Li L, Sathasivam HP, Chan MSA, Rajadurai P, et al.
    Sci Rep, 2020 04 09;10(1):6115.
    PMID: 32273550 DOI: 10.1038/s41598-020-63150-0
    Nasopharyngeal carcinoma (NPC) is a highly metastatic cancer that is consistently associated with Epstein-Barr virus (EBV) infection. In this study, we identify for the first time a role for monoamine oxidase A (MAOA) in NPC. MAOA is a mitochondrial enzyme that catalyzes oxidative deamination of neurotransmitters and dietary amines. Depending on the cancer type, MAOA can either have a tumour-promoting or tumour-suppressive role. We show that MAOA is down-regulated in primary NPC tissues and its down-regulation enhances the migration of NPC cells. In addition, we found that EBV infection can down-regulate MAOA expression in both pre-malignant and malignant nasopharyngeal epithelial (NPE) cells. We further demonstrate that MAOA is down-regulated as a result of IL-6/IL-6R/STAT3 signalling and epigenetic mechanisms, effects that might be attributed to EBV infection in NPE cells. Taken together, our data point to a central role for EBV in mediating the tumour suppressive effects of MAOA and that loss of MAOA could be an important step in the pathogenesis of NPC.
    Matched MeSH terms: Nasopharyngeal Neoplasms/genetics
Filters
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links