A let-7b binding site SNP in the 3'-UTR of the Bcl-xL gene enhances resistance to 5-fluorouracil and doxorubicin in breast cancer cells

摘要: The development of acquired resistance to chemotherapy is a major obstacle in the successful treatment cancer. In breast cancer cells, B-cell lymphoma-extra large (Bcl-xL) involved various chemotherapeutic agents; therefore, preliminary biological prediction was performed identify putative binding site for let-7b 3′-untranslated region (UTR) Bcl-xL gene and single nucleotide polymorphism (SNP) within this region. present study investigated association between SNP rs3208684 A>C agent cells. data indicated that negatively regulates expression appears sensitize MCF-7 cells agents 5-fluorouracil (5-FU) doxorubicin. Furthermore, demonstrated enhance protein by disrupting 3′-UTR and, overexpression presence mutant (C allele) significantly increased 5-FU doxorubicin resistance. Thus, results demonstrate may upregulate decreasing Bcl-xL.