RESUMO
BACKGROUND: Overexpression of microRNA-182 (miR-182) is found in various human cancers, including non-small cell lung cancer (NSCLC). Our aim is to investigate the association of miR-182 expression with the sensitivity of NSCLC to cisplatin. METHODS: TaqMan RT-PCR or Western blot assay was performed to detect the expression of mature miR-182 and programmed cell death 4 (PDCD4) protein. miR-182 and (or) PDCD4 depleted cell lines were generated using miR-182 inhibitor and (or) siRNA. The viabilities of treated cells were analyzed using MTT assay. RESULTS: The expression level of miR-182 in A549 cell line was significantly higher than that in NHBE cell line (p < 0.01). Transfection of miR-182 inhibitor induced sensitivity of A549 cells to cisplatin. A549 cells transfected with PDCD4 siRNA became more resistant to cisplatin therapy. We found an increase PDCD4 protein level following the transfection of miR-182 inhibitor using Western blot analysis. In addition, the enhanced growth-inhibitory effect by miR-182 inhibitor was weakened after the addition of PDCD4 siRNA. CONCLUSIONS: The results of the present study demonstrated that overexpression of miR-182 may involve in chemoresistance of NSCLC cells to cisplatin by down-regulating PDCD4. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1793467320130186.
Assuntos
Proteínas Reguladoras de Apoptose/biossíntese , Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proteínas de Ligação a RNA/biossíntese , Antineoplásicos/farmacologia , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Linhagem Celular Tumoral , Cisplatino/farmacologia , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Neoplasias Pulmonares/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
The optimal neoadjuvant and adjuvant treatment for gastric cancer remains controversial. We conducted a phase II study using preoperative chemotherapy with modified FOLFOX6 followed by surgical resection and postoperative chemoradiation in patients with gastric carcinoma. Preoperative chemotherapy (two or three cycles) consisted of a 2-h infusion of oxaliplatin (100 mg/m2) and folinic acid (100 mg/m2) followed by a 46-h continuous infusion of 5-fluorouracil (5-FU; 2,400 mg/m2). Surgical resection was planned 4 weeks after the last chemotherapy cycle. Patients underwent postsurgical chemoradiation, receiving a total dose of 45 Gy and 5-FU continuous infusion (350 mg/m2/day). The primary end points were feasibility, overall response rate, and R0 resectability rate after preoperative chemotherapy. The secondary end points were tolerability, treatment-associated complications, disease-free survival, and overall survival. Nineteen patients were enrolled in this study. After neoadjuvant treatment, four patients (21.1%) experienced progressive disease, six patients (31.6%) showed partial remission, and nine patients (47.3%) showed stable disease. In 15 patients (78.9%) R0 resectability could be achieved. Eleven of these patients (73.3%) were able to undergo postoperative chemoradiation. Notably, eight (72.7%) of these patients were disease free and alive at median follow-up of 60 months. Chemotherapy associated neutropenia, neutropenic fever, and anastomotic dehiscence were observed. The combination of preoperative chemotherapy and postoperative chemoradiation is feasible in a significant subset of gastric cancer patients.
