RESUMO
OBJECTIVE: To investigate the role of MALAT1 in the cisplatin treatment of cervical cancer and its underlying mechanism. MATERIALS AND METHODS: The effects of different doses of cisplatin on the proliferation and apoptosis of cervical cancer cells were detected by cell counting kit-8 (CCK-8) assay and apoptosis assay, respectively. We used bioinformatics methods to predict the downstream genes of MALAT1 and examined the expression relationship between the target gene BRWD1 and MALAT1 by quantitative Real-time polymerase chain reaction (qRT-PCR). Western blot was performed to detect the expression levels of apoptosis-related proteins and key genes in PI3K/AKT signaling pathway. RESULTS: After MALAT1 was knocked down, cisplatin showed an inhibited effect on the proliferation of HeLa and C-33A cells in a concentration-dependent manner. After treatment of cervical cancer cells with 5 µM cisplatin, MALAT1 knockdown enhanced the apoptosis of HeLa and C-33A cells, and up-regulated expression of cleaved caspase-3. Over-expression of MALAT1 in cells showed the opposite results. Starbase website was used to predict that MALAT1 might regulate BRWD1 expression. Over-expression of MALAT1 significantly up-regulated the mRNA expression of BRWD1 in HeLa and C-33A cells. After knockdown of BRWD1, cisplatin markedly decreased the proliferation of HeLa and C-33A cells, and promoted cell apoptosis and cleaved caspase-3 expression. Besides, HeLa and C-33A cells showed increased expressions of p-PI3K and p-AKT after MALAT1 was up-regulated. CONCLUSIONS: MALAT1 promoted the cisplatin resistance of cervical cancer, which might be related to regulation of cell apoptosis via BRWD1 and PI3K/AKT pathway.
Assuntos
Antineoplásicos/uso terapêutico , Cisplatino/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Proteína Oncogênica v-akt/efeitos dos fármacos , Fosfatidilinositol 3-Quinases/efeitos dos fármacos , RNA Longo não Codificante/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética , Apoptose/genética , Caspase 3/genética , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Células HeLa , Humanos , Proteínas Nucleares/genéticaRESUMO
ABSTRACT Twenty-one strains of Botrytis cinerea isolated from 13 species of plants grown in China were compared for pathogenicity on Brassica napus, mycelial growth on potato dextrose agar, and presence of double-stranded (ds)RNA. The results showed that the strain CanBc-1 was severely debilitated in pathogenicity and mycelial growth, compared with the 20 virulent strains. A dsRNA of approximately 3.0 kb in length was detected in CanBc-1 and 4 hypovirulent single-conidium (SC) isolates of CanBc-1, but was not detected in the 20 virulent strains of B. cinerea and 4 virulent SC isolates of CanBc-1. Results of the horizontal transmission experiment showed that the hypovirulent trait of CanBc-1 was transmissible and the 3.0-kb dsRNA was involved in the transmission of hypovirulence. Analysis of a 920-bp cDNA sequence generated from the 3.0-kb dsRNA of CanBc-1 indicated that the dsRNA element was a mycovirus, designated as B. cinerea debilitation-related virus (BcDRV). Further analyses showed that BcDRV is closely related to Ophiostoma mitovirus 3b infecting O. novo-ulmi, the causal agent of Dutch elm disease. Mitochondria and cytoplasm in hyphal cells of CanBc-1 became degenerated, compared with the virulent isolate CanBc-1c-66 of B cinerea. This is the first report on the occurrence of Mitovirus-associated hypovirulence in B. cinerea.
