Expression and clinical significance of RhoA in oesophageal cancer

Abstract

Objective To explore the expression and clinical significance of RhoA in oesophageal cancer.Methods The expression of RhoA protein in 140 specimens of primary oesophageal cancer tissues was detected by using immunohistochemical strept avidin-biotin complex (SABC) staining,and its correlation with clinicopathological parameters and prognosis of patients was analyzed.The expression of RhoA mRNA in 30 cases of primary oesophageal cancer tissues and their paired adjacent non-cancer tissues was evaluated by using reverse transcription-polymerase chain reaction (RT-PCR).Results The positive rate of RhoA protein was 60.7％,and the high expression of RhoA protein was significantly associated with depth of invasion (T),lymph node metastasis (N),and clinical TNM stage respectively (P ＜ 0.05).Kaplan-Meier univariate survival analysis revealed that five-year disease-free survival and overall survival rate for patients with high expression of RhoA protein were 6.0％ and 18.1％ respectively,which were significantly lower than 22.6％ and 39.6％ in patients with low expression of RhoA protein (P ＜ 0.05).Multivariate Cox regression analysis revealed that RhoA expression was an independent prognostic factor in disease-free survival and overall survival for patients with oesophageal cancer (Hazard ratio was 1.669 and 1.638 respectively,P ＜ 0.05).The expression of RhoA mRNA was detectable in 30 cases of primary oesophageal cancer tissues (0.49 ±0.21) and their paired adjacent non-cancer tissues (0.28 ±0.19),but the expression in oesophageal cancer tissues was significantly higher than that in paired adjacent non-cancer tissues (P ＜ 0.01).Conclusion High expression of RhoA was detectably in oesophageal cancer,suggesting its important role in the malignant tumorigenesis and progression of oesophageal cancer,and its close correlation with invasion and metastasis of oesophageal cancer. Key words: RhoA ; Oesophageal cancer; Invasion; Metastasis ; Prognosis