Overexpression of BP1, an isoform of Homeobox Gene DLX4, promotes cell proliferation, migration and predicts poor prognosis in endometrial cancer

Abstract

The expression of homeobox gene DLX4 has been verified in some tumors, but not in endometrial cancer. We found that expression of DLX7, a splicing isoform of DLX4, did not show any significant difference in expression between endometrial cancer and endometrium. However, BP1, another splicing isoform of DLX4, was highly expressed in endometrial cancer, and its expression was positively correlated with patient prognosis, cancer pathological grade, tumor invasion and metastasis. Lentiviral-mediated expression of BP1 in HEC-1-B cells accelerated the cell cycle progression from G0/G1 into S phase, and promoted cell proliferation and migration both in vitro and in vivo. Real-time PCR and western blotting showed that the expression levels of p15, p21 and E-cadherin significantly decreased, and levels of cyclinD1 and MMP-2 increased in endometrial cancer cells. In conclusion, our results demonstrate that high expression of BP1 is associated with poor prognosis in patients with endometrial cancer and promotes cell proliferation and migration.