RESUMEN
Genomic instability (GIN) is pivotal in regulating tumor drug resistance, which blocked the treatment of triple negative breast cancer (TNBC). Although recent studies implied that non-coding RNA (ncRNA)-mediated autophagy abolishment promoted tumorigenesis by up-regulation of GIN, autophagy was known as a risk factor in tumor drug resistance. However, previous study also pointed that up-regulation of autophagy promoted GIN. Therefore, the relationship between autophagy and GIN is not clear, and more work is needed. And, if an ncRNA is identified to be a co-regulator of autophagy and GIN, it will be a potential therapy target of chemotherapy resistance in TNBC. In our study, we recognized both autophagy-GIN-associated microRNA (mi-26a-5p) by big data analysis, which was prognosis-correlated in breast cancer. Next, we identified the up-stream regulators (long non-coding RNA, lncRNA) and down-stream targets of miR-26a-5p by bioinformatics analysis (online public databases). Finally, we established lncRNA OTUD6B-AS1/miR-26a-5p/MTDH signaling pathway, and verified their functions by cytological, molecular biological and zoological experiments. In general, our study found (1) miR-26a-5p was a protective factor of breast cancer, while OTUD6B-AS1 and MTDH were risk factors; (2) OTUD6B-AS1 was the up-stream regulator of miR-26a-5p verified by luciferase; (3) up-regulation of miR-26a-5p and down-regulation of MTDH promoted cellular cytotoxicity of paclitaxel (PTX) in vitro and in vivo. (4) down-regulation of miR-26a-5p, overexpression of MTDH and OTUD6B-AS1 promoted autophagy and DNA damage; (5) up-regulation of OTUD6B-AS1 and MTDH inhibited DNA damage response (DDR) by inhibiting the phosphorylated activation of RAD51, ATR and ATM.
Asunto(s)
Resistencia a Antineoplásicos/genética , MicroARNs/genética , Paclitaxel/farmacología , ARN Largo no Codificante/genética , Neoplasias de la Mama Triple Negativas , Animales , Antineoplásicos/farmacología , Autofagia/genética , Línea Celular Tumoral , Femenino , Inestabilidad Genómica/genética , Humanos , Proteínas de la Membrana/genética , Ratones Desnudos , Proteínas de Unión al ARN/genética , Neoplasias de la Mama Triple Negativas/genética , Neoplasias de la Mama Triple Negativas/metabolismoRESUMEN
Cancer has always been an enormous threat to human health and survival. Surgery, radiotherapy, and chemotherapy could improve the survival of cancer patients, but most patients with advanced cancer usually have a poor survival or could not afford the high cost of chemotherapy. The emergence of oncolytic viruses provided a new strategy for us to alleviate or even cure malignant tumors. An oncolytic virus can be described as a genetically engineered or naturally existing virus that can selectively replicate in cancer cells and then kill them without damaging the healthy cells. There have been many kinds of oncolytic viruses, such as herpes simplex virus, adenovirus, and Coxsackievirus. Moreover, they have different clinical applications in cancer treatment. This review focused on the clinical application of oncolytic virus and predicted the prospect by analyzing the advantages and disadvantages of oncolytic virotherapy.
RESUMEN
Cancer-associated fibroblasts (CAFs), which are an important component of the tumor microenvironment, have been identified in the blood circulation of patients with cancer metastasis, and metastatic cancer cells can recruit circulating CAFs. However, primary carcinoma sites usually regulate the behavior of metastatic cancer cells through exosomes. Here, we hypothesized that cancer-derived exosomes could enhance CAF recruitment. Exosomes secreted by pancreatic cancer cells (PANC-1 and MIA PaCa-2) were isolated and characterized. The ability of pancreatic cancer to recruit pancreatic stellate cells (PSCs) was assessed with Transwell assays in vitro and bioluminescent imaging in a mouse model in vivo, and the underlying molecular mechanism was also investigated. The results showed that pancreatic cancer cell-derived exosomes (Exo-Pan and Exo-Mia) promoted the pancreatic cancer recruitment of PSCs. This effect was mediated partially by the transfer of the exosomal protein Lin28B to the recipient cells to activate the Lin28B/let-7/HMGA2/PDGFB signaling pathway. These results suggested that exosomes derived from local cancer could promote the formation of distant metastases through transferring the exosomal protein Lin28B to the metastatic cancer cells.
RESUMEN
SAV1 is a human homolog of salvador that contains two protein-protein interaction modules known as WW domains and acts as a scaffolding protein for Hpo and Warts. SAV1 is known to be a tumor suppressor, but its clinical and prognostic implications remain elusive. This study aimed at evaluating the prognostic significance and associated expression of SAV1 in pancreatic ductal adenocarcinoma (PDAC) patients. The expression of SAV1 in tissue specimens of PDAC patients were assayed with immunohistochemistry on a tissue microarray. The correlations between SAV1 expression and clinicopathological characteristics were analyzed by Pearson's chi-square test, Fisher's exact test, and Spearman's rank. The prognostic factors for overall survival were analyzed by univariate and multivariate Cox regression. The percentage of SAV1 expression in PDAC (50.6 %) was significantly lower than those in paratumor tissues (69.9 %) (P = 0.017). Expression of SAV1 was only significantly correlated with histological differentiation (P = 0.025) and N classification (P = 0.009). On multivariate analysis, elevated expression of SAV1 and N0 was a significant favorable prognostic factor of OS. Our study demonstrated for the first time that lower expression of SAV1 might be involved in the progression of PDAC, suggesting that SAV1 may be a potential prognostic marker and target for PDAC therapy.