Objective Studies show that the ERCC1 gene may be involved in secondary cisplatin resistance.This article aims to investigate the effects of shRNA targeting silencing excision repair cross-complementation group 1 (ERCC1-shRNA) on the proliferation and apoptosis of lung cancer A549/DDP cells treated with different concentrations of cisplatin.Methods Lung cancer A549/DDP cells were divided into a negative control, a blank control, an ERCC1-shRNA1, and an ERCC1-shRNA2 group.Human interfering RNA (RNAi) targeting the human ERCC1 gene was constructed and transfected into the A549/DDP cells using Lipofectamine 2000.The mRNA and protein expressions of ERCC1 in the A549/DDP cells were detected by real-time PCR and Western blot respectively, the proliferation-inhibition rate was assessed by MTT, and their cell cycle and apoptosis were determined by flow cytometry.Results ERCC1-shRNA was successfully constructed and transfected into the A549/DDP cells.Both the mRNA and protein expressions of ERCC1 were significantly lower in the ERCC1-shRNA1 (0.20±0.04 and 0.24±0.10) and ERCC1-shRNA2 (0.47±0.28 and 0.37±0.11) than in the negative control (0.96±0.12 and 1.32±0.13) and blank control groups (0.84±0.07 and 1.45±0.23) (P<0.01).Compared with the negative and blank control groups, the ERCC1-shRNA1 group showed a significantly decreased IC50 value (16.71±2.33 and 16.69±1.69 vs 7.78±0.54, P<0.01) and an increased proportion of G0/G1 phase cells ([72.87±3.23] and [71.75±4.56] vs [82.99±4.23]%, P<0.05), with the cell cycle arrested in the G0/G1 phase.The apoptosis rate of the cells in the ERCC1-shRNA1 group was remarkably lower after treated with cisplatin at the concentrations of 6.25 and 12.5 μg/mL than at 0 μg/mL ([8.17±0.65] and [11.91±1.41] vs [29.97±3.14]%, P<0.05).Conclusion ERCC1-shRNA can inhibit the proliferation and enhance the apoptosis of A549/DDP cells by silencing the expression of the ERCC1 gene.

AIM: To investigate the effect of gastrodin on the expression of brain-derived neurotrophic factor (BDNF) and interleukin-6 (IL-6) in the striatum of cerebral ischemia rats, and to explore the potential mechanism of gastrodin in treating cerebral ischemia. METHODS: The rats were randomly divided into four groups: normal, sham, model, and gastrodin groups, each consisting of 10 rats. After successful modeling using middle cerebral artery occlusion (MCAO), the gastrodin group received intraperitoneal injection of gastrodin injection at a dose of 10 mg/kg once a day for 14 consecutive days. Pathological changes in striatal neurons were observed using Nissl staining. Immunohistochemistry was utilized to detect positive expression of BDNF and IL-6 proteins in the striatum. Additionally, immunoblot analysis was performed to determine the expression levels of BDNF and IL-6 proteins in the striatum. RESULTS: Nissl staining revealed clear and intact structures of striatal neurons in the normal and sham groups, with tightly arranged cells. In the model group, the number of cells was significantly reduced compared to the sham group (P<0.01), and there was a noticeable cytosolic atrophy and loose cell arrangement. The gastrodin group showed a significant increase in the number of Nissl-positive neurons compared to the model group (P<0.01), and there was also a significant improvement in cell morphology. The results of immunohistochemistry and immunoblot were consistent, and there was no statistically significant difference in BDNF and IL-6 protein expression between the normal group and the sham group (P>0.05). Compared to the sham group, the model group showed a decrease in the protein expression level of BDNF in the striatum on the ischemic side (P<0.01) and an increase in the protein expression level of IL-6 (P<0.05, P<0.01). In contrast, the gastrodin group showed an increase in the protein expression level of BDNF in the striatum on the ischemic side (P<0.05, P<0.01) and a decrease in the protein expression level of IL-6 (P< 0.05, P<0.01) compared to the model group. CONCLUSION: Gastrodin has a significant protective effect on striatal injury caused by cerebral ischemia, and its mechanism may be related to the up-regulation of the anti-inflammatory factor BDNF and the down-regulation of the pro-inflammatory factor IL-6.