Although the molecular mechanisms driving chemoresistance and relapse of
ovarian cancer have been widely studied, the key molecules have not been identified. In this study, the expression of
miR-29b messenger RNA (
mRNA) and its targeted genes,
myeloid cell leukemia sequence 1,
mitogen-activated protein kinase 10 (MAPK10), and
autophagy-related protein 9A (ATG9A), were investigated in ovarian
carcinomas, and their associations with clinicopathological characteristics and survival of patients with
ovarian cancer were analyzed. The
protein expression of MCL1, MAPK10, and ATG9A was measured using immunohistochemistry.
miR-29b mRNA and ATG9A gene
mRNA levels were measured by real-time polymerase chain reaction. Results demonstrated that the percentage of MCL1, MAPK10, and ATG9A
protein-positive cases were significantly higher, whereas
miR-29b was significantly lower in ovarian serous, mucinous, and clear cell
carcinomas than that in normal tissues. MAPK10 was significantly associated with higher histopathologic grading. The percentage of positive
myeloid cell leukemia sequence 1, ATG9A, and MAPK10
protein expression and low
miR-29b mRNA expression were significantly higher in cases with clinical stage III and IV
ovarian cancer than in cases with clinical stage II
ovarian cancer. High ATG9A
protein and low
miR-29b mRNA expression were significantly associated with relapse. Univariate Kaplan-Meier analysis showed a negative correlation between MAPK10 or ATG9A
protein expression and overall as well as progression-free survival, whereas a positive correlation was observed between
miR-29b mRNA expression and overall as well as progression-free survival. Multivariate Cox regression analysis showed that elevated MAPK10 or ATG9A
protein and lowered
miR-29b mRNA expression in ovarian
carcinoma was an independent poor prognostic predictor. Our study suggested that
miR-29b mRNA, MAPK10
protein expression, and ATG9A
protein expression are closely related to chemosensitivity of ovarian
carcinoma.