BACH1 silencing by siRNA inhibits migration of HT-29 colon cancer cells through reduction of metastasis-related genes.

BACKGROUND: Metastasis to distant organs is a hallmark of many tumor cells. BACH1 (BTB and CNC homology 1) is a transcriptional factor which promotes the migration and invasion of breast cancer cells. BACH1 expression and its target genes are intimately associated with the metastasis possibility of clinical samples, and BACH1 reduction leads to meaningful depletion in metastasis. The evaluation of BACH1 role in colon cancer remains elusive. This study seeks to further investigate the role of BACH1 in colon cancer cells.

METHODS: Quantitative RT-PCR (qRT-PCR) was used to detect BACH1 expression and other related metastatic genes following siRNA knockdown in colon cancer HT-29 cells. And the protein level assessed by Western blot. MTT assay was to measure the changed cell viability after BACH1 siRNA transfection. Scratch-wound motility assays measured capacity of tumor cell migration of HT-29 cells after BACH1 silencing.

RESULTS: The inhibitory effect of BACH1 was performed by siRNA knockdown using highly metastatic HT-29 colon cell lines. Quantitative RT-PCR and Western blot analysis revealed that the expression levels of BACH1 mRNA and protein in HT29 cells were significantly suppressed after transfection. Conversely, the BACH1 expression increased migration. Also the CXCR4 and MMP1 expression levels decreased following BACH1 knockdown in HT-29 cells.

CONCLUSION: Our results indicated that BACH1 down-regulation in HT29 CRC cells had no effect on cell growth but did inhibit cell migration by decreasing metastasis-related genes expression. Collectively, these results suggest that BACH1 may function as an oncogenic driver in colon cancer and may represent as a potential target of gene therapy for CRC treatment.