FLOT2 overexpression is associated with the progression and prognosis of human colorectal cancer

Altered expression of flotillin-2 (FLOT2) has been identified in certain types of cancer, including breast cancer and melanoma; however, to the best of our knowledge, the association between the FLOT2 expression level and colorectal cancer (CRC) remains to be determined. The aim of the present study was to investigate the clinical and prognostic significance of FLOT2 in CRC. The expression of FLOT2 was determined in seven CRC cell lines and one normal colon cell line, and it was identified that FLOT2 was increased in CRC cell lines, suggesting that FLOT2 exhibited an association with CRCs. In addition, FLOT2 protein levels were investigated in primary CRC tissues and corresponding non-cancerous colon tissues from 8 patients. Compared with non-cancerous tissues, FLOT2 protein was apparently upregulated in CRC tissues. To validate this result, an immunohistochemistry assay was performed and it was identified that FLOT2 levels were increased in CRC tissues. Clinical analysis identified that increased expression of FLOT2 was associated with the depth of invasion, lymph node metastasis, distant metastasis and American Joint Committee on Cancer stage of CRCs. Furthermore, multivariate analysis using the Cox regression model indicated that increased FLOT2 expression was an independent prognostic factor in patients with CRC (P=0.013). Taken together, the results of the present study suggest that overexpression of FLOT2 contributes to the progression of CRC and indicate that FLOT2 is a novel target for the treatment of CRC.