1. Abstract Objectives: To screen out sensitive chemotherapy regimens for cancer stem cells (CSCs) from colorectal cancer (CRC) pa- tients in northeast Sichuan of China and provide the basis for "re-gional precision" targeted therapy. Methods: Primary colorectal CSCs from the northeast Sichuan of China were extracted using the CRC CSCs protocol de- veloped previously. The chemotherapeutic agents, FOLFOX, Curcumin, Salinomycin, and Mithramycin-A (Mit-A) were used to assess changes in the proportion of CD133+, CD44+ and CD133+CD44+ cells in each group using flow cytometry. Colony Formation Assay, SphereForming Assay, Cell migration and cell invasion assay, and CCK-8 were utilized to detect the prolifera- tion, migration and invasion ability of primary CRC CSCs in vitro.QT-PCR detected expression of the core CSC genes, Oct-4, Sox2, Nanog, and KLF4, CRC CSCs marker genes, and Wnt/βcatenin pathway related genes. By comparing the effectiveness of the threeregimens on primary CRC CSCs in northeast Sichuan of China, chemotherapy regimens that are sensitive to CSCs in CRC patients from this area could be screened out. Results: The proportion of CD133+CD44+ cells in the DLD1 cell line reached 54.42%, and the proportion of CD133+CD44+ cells in primary CRC cells was 13.72%. In response to the C4 regimen, the proportions of CD133+,CD44+ and CD133+CD44+ cells were significantly reduced, the volume and number of cell spherules were suppressed, cell survival rate was significantly re- duced, and almost no cells were able to migrated or invade. In addition, there was a reduction in mRNA expression of the CSC related genes, Oct-4, Nanog, SOX2 and KLF4, the CRC CSCsre-lated gene, Lgr5, the mesenchymal genes, Vimentin and Snail, andWnt/β-catenin pathway related genes. Conclusion: The combination of FOLFOX and Mithramycin A can effectively inhibit the occurrence, metastasis and recurrence of colorectal cancer CSCs and inhibit the dryness and mesenchymal properties using the Wnt/β-catenin and TGFβ1/snail pathways.
2. IntroductionColorectal cancer (CRC) is second only to lung cancer as the most common malignancy, with more than 1.9 million new diagnoses made each year in developed countries [1-3]. CRC incidence is increasing worldwide likely as a result of changes in human be- havior, including reduced exercise, increased consumption of ani- mal-derived foods, and excessive alcohol intake [4]. The incidence of CRC in transitioning countries is four times that of other areas, in particular North America and Europe [5,6]. CRC incidence in Asia is increasing in countries such as China that are becoming more westernized [7-9]. Of note, CRC accounts for nearly 45%of all cancer-related deaths due to late diagnoses in China [10,11]. FOLFOX is one of the most common first-line chemotherapeutic drugs used to treat a variety of cancers [12,13]. CRC patients are frequently resistant to chemotherapy regimens using FOLFOX, however, and often require additional conventional chemothera- peutic agents such as Capecitabine, Irinotecan, angiogenesis inhib-
Wei Ying* .FOLFOX Combined with Mithramycin-A Has A Cytotoxic Effect On The Primary Colorectal Cancer Stem Cells . Annals of Clinical and Medical Case Reports 2022