Xeroderma pigmentosum, complementation group C (XPC) is an accessory recognition gene involved in the nucleotide excision repair (NER) pathway, which is activated during the initial DNA damage recognition stage. It participates in the regulation of DNA damage-induced proliferation and apoptosis. Emerging evidence demonstrates that upregulation of XPC increases the resistance of several tumor cell types to cytotoxic drugs. In addition, it can predict poor patient outcome for non-small cell lung cancer (NSCLC). However, the mechanisms linking upregulation of XPC and drug resistance in lung cancer are still unclear. In the present study, we aimed to confirm whether XPC was involved in the reversal of the cisplatin (DDP) resistance in drug-resistant A549/DDP lung adenocarcinoma cells. RT-PCR and western blot assays were used to examine XPC mRNA and protein expression levels. Cell viability was assessed by CCK-8 assay. The knockdown of XPC was achieved in A549/DDP cells using si-RNA, whereas cell proliferation and apoptosis were assessed by wound healing assay and flow cytometric analysis, respectively. The median inhibitory concentration (IC 50 ) value of DDP was assessed by CCK-8 assay. Western blot assays were conducted for the examination of caspase-9/3, Bax and Bcl-2 protein levels, whereas the activation of the PI3K/Akt/mTOR signaling pathway was investigated in XPC-knockdown cells. High expression of XPC was noted in A549/DDP cells compared with that in A549 cells, which was associated with DDP resistance. XPC silencing significantly inhibited A549/DDP cell proliferation and increased the induction of apoptosis. In addition, XPC knockdown decreased the expression levels of the Akt/mTOR signaling proteins and the expression of their downstream mediator. The data of the present study revealed that XPC inhibition rescued DDP resistance in lung adenocarcinoma cells, which was dependent on the Akt/mTOR signaling pathway. Collectively, XPC may be considered a new strategy for curing DDP-resistant lung cancer and may improve the efficacy of conventional chemotherapy.

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The human ether-ago go related potassium channel 1 (hERG1) is a functional component of the voltage-gated Kv11.1 potassium channel, which is commonly described as a crucial factor in the tumorigenesis of a variety of tumors. Ovarian cancer is one of the most severe types of cancer, with an extremely poor prognosis. Advances have been made in recent years; however, drug resistance and tumor recurrence remain critical issues underlying satisfactory treatment outcomes. Therefore, more effective antitumor agents with low levels of drug resistance for ovarian cancer treatment are urgently required in clinical practice. In the present study, hERG1 mRNA expression in ovarian tumor tissues and cell lines were measured by reverse transcription-quantitative polymerase chain reaction. Immunohistochemistry and western blotting were used to assess the expression levels of hERG1 protein. Cell proliferation, migration and invasion were assessed by Cell Counting Kit-8 assay and Transwell assay. A tumor xenograft assay was used to determine the growth of tumors in vivo. It was demonstrated that the expression levels of hERG1 were significantly elevated in ovarian cancer tissues and expressed in ovarian cancer cell lines, particularly in SKOV3 cells. Abnormal hERG1 expression was significantly associated with the proliferation, migration and invasion abilities of ovarian cancer. In addition, berberine (BBR) may be used as a potential drug in the treatment of ovarian cancer, possibly due to its inhibitory effects on the hERG1 channels. In conclusion, the present study demonstrated that hERG1 may be a potential therapeutic target in the treatment of ovarian cancer and provided novel insights into the mechanism underlying the antitumor effects of BBR in ovarian cancer.

Promoting the reduction of chemical fertilizers is an important measure to promote the green and sustainable development of agriculture. Farmland transfer is a new way to minimize the need of chemical fertilizers. However, there is debate over this causality. This paper examines the relationship between farmland transfer and chemical fertilizer reduction. After the theoretical analysis, based on the data of 442 corn farmers in Heilongjiang Province, the study employed the endogenous switching probit model to empirically test the effect of farmland transfer on the reduction of chemical fertilizer. The study finds that in the survey area, the overall actual chemical fertilizer application rate was 12.12 kg/mu higher than the economic optimal application rate, which had more room for chemical fertilizer reduction. Moreover, farmland transfer-in reduced the chemical fertilizer application during corn production. If farmland transfer-in farmers decided not to transfer into the farmland, the chemical fertilizer reduction treatment effect would decrease, while it would increase if farmland non-transfer-in farmers decided to transfer into the farmland. Finally, the chemical fertilizer reduction treatment effect would decrease if farmers who had transferred into farmland concentratedly chose to transfer into farmland dispersedly, while it would increase if farmers who had transferred into farmland dispersedly chose to transfer into farmland concentratedly. These findings can provide experience for achieving more effective farmland transfer and chemical fertilizer reduction.

A neuropeptide precursor encoded by Bta06987 associates with AKH neuropeptide. In the AKH/RPCH family, these members have been demonstrated to participate in energy mobilization in many insects. In our research, the Bta06987 gene from Bemisia tabaci was cloned, and the amino acid sequence analysis was performed. During the starvation of B. tabaci, the mRNA level of Bta06987 showed a significant elevation. We investigated the functions of Bta06987 in B. tabaci using RNA interference (RNAi), and the adult females of B. tabaci after being fed with dsBta06987 showed a higher glycogen and triglyceride levels and lower trehalose content than the control. Furthermore, in the electrical penetration graph (EPG) experiment, B. tabaci showed changes in feeding behavior after feeding with dsBta06987, such as the reduction in parameters of E waveform percentage and total feeding time. Our findings might be helpful in developing strategies to control pest and plant virus transmission.