Author(s)

Rakesh Naidu^1*, Lim Vin Nee², Mak Joon Wah², Kevin Moissinac³, A. Rahman A. Jamal⁴, Isa Mohd Rose⁵, Yunus Gul Alif Gul⁶, Patricia Lim Kim Chooi², Gregory Tan Jin San⁷

¹School of Medicine and Health Sciences, Monash University Malaysia, Selangor, Malaysia.
²International Medical University, Kuala Lumpur, Malaysia.
³Department of Surgery, Penang Medical College, Pulau Pinang, Malaysia.
⁴Department of Paediatrics, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
⁵Department of Pathology, Faculty of Medicine, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia.
⁶Department of Surgery, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Selangor, Malaysia.
⁷School of Health Sciences, The University of Notre Dame Australia, Fremantle, Australia.

Background: The purpose of the present study is to investigate the expression levels of STAT3, pSTAT3, MMP-7 and VEGF in colorectal adenocarcinoma, and also to determine association with the clinico-pathological parameters and co-expression of these genes. Methods: An immunohistochemical method was used to evaluate the expression of MMP-7 and VEGF genes in 93 archival tissues whereas STAT3 and pSTAT3 expression was determined in 75 cases. Results: Overexpression of STAT3 was detected in 26.7% (20/75), pSTAT3 in 13.4% (10/75), MMP-7 in 38.8% (36/93) and VEGF in 59.2% (55/93) of the colorectal carcinomas. STAT3, MMP-7 and VEGF immunopositivity were significantly correlated with poorly-differentiated tumors (P = 0.004; P = 0.03; P = 0.002, respectively) but not with other parameters. However, pSTAT3 immunostaining was not significantly associated with the clinico-pathological characteristics. Significant relationship was noted between overexpression of pSTAT3 and STAT3 (P < 0.001), pSTAT3 and VEGF (P = 0.044), pSTAT3 and MMP-7 (P = 0.003), and STAT3 and VEGF (P = 0.037) but marginal association was detected between STAT3 and MMP-7 (P = 0.057), and MMP-7 and VEGF (P = 0.052). Conclusion: Our data suggest that expression of these genes may have an important role in tumor dedifferentiation and may be useful as indicators of biologic aggressiveness. Co-expression of the biomarkers by cancer cells may have important implications in colorectal cancer biology and could be useful biological markers of the malignant phenotype.

STAT3, pSTAT3, MMP-7, VEGF, Colorectal Adenocarcinoma

Naidu, R. , Nee, L. , Wah, M. , Moissinac, K. , Jamal, A. , Rose, I. , Gul, Y. , Chooi, P. and San, G. (2014) Protein Expression of STAT3, pSTAT3, MMP-7 and VEGF in Colorectal Adenocarcinoma: An Immunohistochemical Study. Journal of Cancer Therapy, 5, 1175-1185. doi: 10.4236/jct.2014.513119.