Study on the mechanism of oral administration of tetrandrine during neoadjuvant chemotherapy for colon cancer

Abstract

Colon cancer is a digestive tract tumor with one of the highest frequencies worldwide, and with a high fatality rate. The present study aimed to investigate the expression and regulation of inflammatory factors in tumor tissues, monocytes and blood samples in patients with colon cancer (n=46) following treatment with neoadjuvant chemotherapy combined with tetrandrine. All patients underwent tumor resection after neoadjuvant chemotherapy. In the experimental group, 20 cases took tetrandrine during chemotherapy, while in the control group, 26 cases underwent chemotherapy without tetrandrine. Reverse transcription-quantitative PCR and western blotting were performed to detect the mRNA and protein expression levels of TNF-α. ELISA was used to detect the cytokine/chemokine expression levels [IL-15, IL-1β and IL-6, as well as chemokine ligand (CCL)2, CCL5, CCL20, chemokine (C-X-C motif) ligand CXCL1, CXCL2, CXCL3, CXCL5 and CXCL10 in the culture supernatant of colon cancer tissue]. Human blood mononuclear cells were cultured, and cytokine release was determined by ELISA. Cell proliferation ability was assessed using the MTT assay. Compared with the control group, the mRNA and protein expression levels of tumor necrosis factor-α (TNF-α) were downregulated in tumor tissues and serum and the serum levels of IL-15, IL-1β and IL-6 were relatively low in the experimental group. The expression levels of CCL5, CXCL2 and CXCL10 in the supernatant of cancer tissue culture were relatively low, compared with the conditioned medium prepared from tumor tissues of patients not receiving tetrandrine. When the cultured blood mononuclear cells were stimulated by the tissue culture supernatant from the experimental group, less IL-15, IL-1β and IL-6 were released, compared with the medium of tumor tissues of patients not taking tetrandrine. Following stimulation with the tissue culture supernatant from the experimental group, the proliferation ability of HCT116 colon cancer cells significantly declined. During chemotherapy of patients with colon cancer, tetrandrine may inhibit the expression of TNF-α in cancer tissues and blood, reduce the release of inflammatory factors and chemokines and decrease cancer cell proliferation. These findings provide a theoretical basis for the treatment of colon cancer in the clinic.