Melanoma associated antigen (MAGE)-A3 promotes cell proliferation and chemotherapeutic drug resistance in gastric cancer.
Cell Oncol (Dordr)
; 39(2): 175-86, 2016 Apr.
Article
en En
| MEDLINE
| ID: mdl-26868260
ABSTRACT
BACKGROUND:
Melanoma-associated antigen (MAGE)-A3 is a member of the family of cancer-testis antigens and has been found to be epigenetically regulated and aberrantly expressed in various cancer types. It has also been found that MAGE-A3 expression may correlate with an aggressive clinical course and with chemo-resistance. The objectives of this study were to assess the relationship between MAGE-A3 promoter methylation and expression and (1) gastric cancer patient survival and (2) its functional consequences in gastric cancer-derived cells.METHODS:
Samples from two independent gastric cancer cohorts (including matched non-malignant gastric samples) were included in this study. MAGE-A3 methylation and mRNA expression levels were determined by methylation-specific PCR (MSP) and quantitative real-time PCR (qPCR), respectively. MAGE-A3 expression was knocked down in MKN1 gastric cancer-derived cells using miRNAs. In addition, in vitro cell proliferation, colony formation, apoptosis, cell cycle, drug treatment, immunohistochemistry and Western blot assays were performed.RESULTS:
Clinical analysis of 223 primary patient-derived samples (ntumor = 161, nnormal = 62) showed a significant inverse correlation between MAGE-A3 promoter methylation and expression in the cancer samples (R = -0.63, p = 5.99e-19). A lower MAGE-A3 methylation level was found to be associated with a worse patient survival (HR 1.5, 95 % CI 1.02-2.37, p = 0.04). In addition, we found that miRNA-mediated knockdown of MAGE-A3 expression in MKN1 cells caused a reduction in its proliferation and colony forming capacities, respectively. Under stress conditions MAGE-A3 was found to regulate the expression of Bax and p21. MAGE-A3 knock down also led to an increase in Puma and Noxa expression, thus contributing to an enhanced docetaxel sensitivity in the gastric cancer-derived cells.CONCLUSIONS:
From our results we conclude that MAGE-A3 expression is regulated epigenetically by promoter methylation, and that its expression contributes to gastric cell proliferation and drug sensitivity. This study underscores the potential implications of MAGE-A3 as a therapeutic target and prognostic marker in gastric cancer patients.Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Neoplasias Gástricas
/
Resistencia a Antineoplásicos
/
Antígenos de Neoplasias
/
Proteínas de Neoplasias
/
Antineoplásicos
Tipo de estudio:
Risk_factors_studies
Límite:
Humans
Idioma:
En
Revista:
Cell Oncol (Dordr)
Año:
2016
Tipo del documento:
Article
País de afiliación:
Singapur