Exploring the Mechanism of Resistance to vincristine in Breast Cancer Cells through Transcriptome Sequencing Technology

Breast cancer has replaced lung cancer as the leading cancer globally, but various chemotherapy drugs for breast cancer are prone to generate resistance, especially in patients with distant metastases who are susceptible to multiple chemotherapy drug resistance, these always leading to treatment failure. vincristine (VCR) is an alkaloid extracted from Catharanthus roseus and is often used in combination with other chemotherapy drugs to treat various types of cancer, including breast cancer. Recently, we conducted research on the development of resistance to VCR using transcriptome sequencing technology. Firstly, we used the gradient increase of VCR concentration to produce a VCR-resistant breast cancer cell line. Mechanistically, we further extracted RNA from the VCR-resistant breast cancer cell line and sequenced the transcriptome. Further analysis showed changes in various gene expression levels in the VCR-resistant breast cancer cell line. Meanwhile, the analysis of splicing events also indicated that variable splicing events change in the VCR-resistant breast cancer cell line. Further validation showed that multiple gene expression levels, including 1L1B, were altered in the VCR-resistant breast cancer cell line, and these gene expression changes were related to VCR resistance. Our results provide a theoretical basis for exploring the mechanism of VCR resistance clinically. In order to investigate the specific mechanism underlying the development of Vincristine resistance in breast cancer treatment, we constructed a Vincristine-resistant breast cancer cell line MCF7/VCR. Firstly, we treated MCF7 cells with different concentrations of VCR in a 96-well plate, using 1nM for 5 days, followed by 5nM, 10nM, 50nM, 100nM, 500nM, 1000nM, 5000nM, and 10000nM for 5 days each. Eventually, the surviving MCF7 cells were expanded and screened to obtain the Vincristine-resistant MCF7 cell line. The IC50 of wild-type and MCF7/VCR cells to Vincristine were measured using the CCK8 method, and were found to be 7.371 nM and 10574 nM, respectively