Influence of high glucose state on bromopyruvate-induced cytotoxity by human colon cancer cell lines

BackgroundAttention must be paid to chemotherapy for cancer patients in a hyperglycemia state. It is difficult for chemotherapy to cure cancer in patients in a hyperglycemia state. This study was carried out to determine the change in cell viability after treatment with bromopyruvate, which is an alkylating drug with anti-tumor activity, in a high glucose condition.MethodsThe function of l-lactate and bromopyruvate transport was studied using human colon cancer cell lines (LoVo and HT-29) and radiolabeled l-lactate and bromopyruvate. Cell viability was monitored by the trypan blue exclusion assay. The expression level of human monocarboxylate transporter 1 (hMCT1) was evaluated by Western blot analysis.ResultsBromopyruvate-induced cell death was suppressed by a high glucose condition. l-Lactate and bromopyruvate uptake were suppressed by a high glucose condition. hMCT1 as a bromopyruvate carrier was functionally expressed in the cells. However, the expression of hMCT1 was suppressed by a high glucose state.ConclusionsDown-regulation of hMCT1 by a high glucose state is one of the possibilities of the bromopyruvate resistance. We should pay scrupulous attention to cancer chemotherapy for patients who have developed diabetes.