Clinicopathological significance and prognostic value of LRP16 expression in colorectal carcinoma

Abstract

Aim: To explore the expression of leukemia related protein 16 (LRP16) in colorectal carcinoma, and analyze its correlation with clinicopathologic features and prognosis.

Methods: Immunohistochemistry for LRP16 was performed in 201 cases of colorectal carcinoma and 60 cases of distal normal mucosa. Medical records were reviewed and clinicopathological analysis was performed.

Results: LRP16 expression was detected in 117 of 201 cases of the colorectal carcinoma and in 21 cases of 60 distal normal mucosa. The expression of LRP16 in carcinoma was significantly higher than that in normal mucosa (chi(2) = 9.999, P = 0.002). LRP16 protein expression was found in 43.3% (52/120) of carcinoma at stage I and II, and 80.2% (65/81) of carcinoma at stage III and IV (chi(2) =27.088, P = 0.001). Correlation between LRP16 expression and clinicopathological factors was significant in differentiation (P = 0.010), tumor size (P = 0.001), infiltrative depth (P = 0.000) and distant metastasis (P = 0.027). The difference of median survival time between cancer patients with LRP16 expression (38.0 mo) and those without was statistically significant (105.0 mo, Log rank = 41.455, P = 0.001). The multivariate survival analysis revealed that LRP16 expression was correlated significantly (Cox's regression: P = 0.001, relative risk = 2.082) with shortened survival in the patients with colorectal cancer.

Conclusion: The expression of LRP16 is related to the degree of differentiation, invasiveness, metastasis and prognosis of colorectal carcinoma.

Figure 1

Positive leukemia related protein 16 (LRP16) expression in colorectal adenocarcinoma. The final score was 6, including 3 scores (strong) related to intensity of staining and 3 scores (> 50%) related to extent of staining. Thus it was defined as strong staining pattern (++). A: Immunohistochemistry (IHC), × 100; B: IHC, × 400.

Figure 2

Negative LRP16 expression in normal colorectal mucosa (IHC, × 400). The final score was 0, including 0 score (negative) related to intensity of staining, and 0 scores (< 5%) related to extent of staining. Thus it was defined as negative expression (-).

Figure 3

Cumulative survival according to LRP16 expression in colorectal cancer patients. The Kaplan-Meier plot of colorectal carcinoma patients (n = 201) demonstrates a significantly lower survival with LRP16 positive expression, P = 0.001.