FOXM1 promotes invasion and migration of colorectal cancer cells partially dependent on HSPA5 transactivation

// Xiaoyong Luo 1, * , Jinke Yao 3, * , Peipei Nie 4, * , Zhiyuan Yang 5 , Hongbo Feng 5 , Pinjia Chen 1 , Xinpeng Shi 1 , Zhengzhi Zou 2 1 Department of Oncology, The Affiliated Luoyang Central Hospital of Zhengzhou University, Luoyang, China 2 MOE Key Laboratory of Laser Life Science and Institute of Laser Life Science, Joint Laboratory of Laser Oncology with Cancer Center of Sun Yat-sen University, College of Biophotonics, South China Normal University, Guangzhou, China 3 Department of General Surgery, Boji-Affiliated Hospital (Zengcheng People’s Hospital), Sun Yat-Sen University, Guangzhou, China 4 KingMed Diagnostics and KingMed School of Laboratory Medicine, Guangzhou Medical University, Guangzhou, China 5 Department of Medcine, The Affiliated Luoyang Central Hospital of Zhengzhou University, Luoyang, China * These authors contributed equally to this work Correspondence to: Xiaoyong Luo, email: xiaoyongluo68@163.com Zhengzhi Zou, email: zouzhengzhi@m.scnu.edu.cn Keywords: FOXM1, HSPA5, migration, invasion, colorectal cancer Received: August 28, 2015      Accepted: March 04, 2016      Published: March 28, 2016 ABSTRACT In this study, to investigate whether endoplastic reticulum (ER) stress correlated with FOXM1 in colorectal cancer, we analysed the mRNA levels of FOXM1 and ER stress markers HSPA5 and spliced XBP1 by qRT-PCR. FOXM1 mRNA levels were found to positively correlate with HSPA5 in colorectal cancer. However, no significant correlation between FOXM1 and spliced XBP1 mRNA levels was found. Theses results suggested the positive correlation between FOXM1 and HSPA5 in colorectal cancer was not associated with ER stress. Next, we provided evidences that FOXM1 promoted HSPA5 transcription by directly binding to and stimulating HSPA5 promoter. Moreover, a FOXM1-binding site mapped between -1019 and -1012 bp of the proximal HSPA5 promoter was identified. In addition, we found that enhancement of cell migration and invasion by FOXM1 was significantly attenuated by depletion of HSPA5 in colorectal cancer cell. Furthermore, FOXM1 triggered colorectal cancer cell migration and invasion was involved in activities of cell-surface HSPA5. Lastly, our results suggested FOXM1 facilitated the activities and expressions of MMP2 and 9 associated with cell-surface HSPA5 in colorectal cancer cells. Moreover, statistically significant positive correlations between FOXM1 and MMP2 mRNA expression, between HSPA5 and MMP2 were found in colorectal cancer tissue specimens. Together, our results suggested that FOXM1-HSPA5 signaling might be considered as a novel molecular target for designing novel therapeutic regimen to control colorectal cancer metastasis and progression.