Overexpression of LARP1 predicts poor prognosis of colorectal cancer and is expected to be a potential therapeutic target.

ABSTRACT

This study investigated the significance of La-related protein 1 (LARP1) in the development and progression of colorectal cancer (CRC). Quantitative real-time polymerase chain reaction and Western blot analyses were carried out to determine the mRNA and protein expression of LARP1 in CRC tumor tissues and paired adjacent normal mucosa. The expression of LARP1 was upregulated in CRC. Immunohistochemical analysis using tissue microarray was performed. A positive correlation between LARP1 and proliferating cell nuclear antigen (PCNA) in the area of proliferation was observed using the Spearman's correlation coefficient test (r = 0.332, P < 0.01). The elevated expression of LARP1 significantly correlated with T stage (P = 0.02), N stage (P = 0.006), M stage (P < 0.001), American Joint Committee on Cancer (AJCC) stage (P = 0.04), differentiation rank (P < 0.001), and PCNA level (P < 0.001). In addition, the inhibitory effect of LARP1 knockdown on CRC cell proliferation was demonstrated using Cell Counting Kit-8 (CCK8) and colony-forming cell (CFC) assays. Multivariate analysis showed that LARP1 was an independent prognostic factor for overall survival (OS; hazard rate (HR) = 0.244; 95 % confidence interval (CI), 0.078-0.769; P = 0.016) and disease-free survival (DFS; HR = 0.281; 95 % CI, 0.086-0.917; P = 0.035) in CRC patients. LARP1 plays an important role in the proliferation of colorectal cancer and represents a new prognostic indicator.