[Expressions of E-cadherin and N-cadherin in prostate cancer and their implications]

To investigate the differences in the expressions of E-cadherin and N-cadherin between high-risk prostate cancer and low- and medium-risk prostate cancer, and analyze their correlation with the age, serum PSA level, and Gleason score of the patients.

We retrospectively analyzed the clinical data of 42 cases of prostate cancer, which were divided into a low- and medium-risk group (group A, n = 15) and a high-risk group (group B, n = 27). We measured the expressions of E-cadherin and N-cadherin by immunohistochemical staining, compared their differences between the two groups, and analyzed their correlation with the age, serum PSA level, and Gleason score of the patients.

Immunohistochemical staining showed that the expression of E-cadherin was significantly higher in group A than in B (6.1 +/- 0.51 vs 4.2 +/- 0.37, P < 0.01), and so was its positive rate (73.3% vs 25.9%, P < 0.05). The positive rate of E-cadherin was also markedly higher in the patients with serum PSA < 20 microg/L than in those with serum PSA > or = 20 microg/L (66.7% vs 29.6%, P < 0.05), and so was it in the patients with the Gleason score 5-7 than in those with 8-10 (60.9% vs 21.1%, P < 0.05). On the contrary, the N-cadherin expression was significantly lower in group A than in B (3.7 +/- 0.32 vs 7.5 +/- 0.58, P < 0.01), and so was its positive rate (13.3% vs 59.3%, P < 0.01). The positive rate of N-cadherin was also remarkably lower in the patients with the Gleason score 5-7 than in those with 8-10 (26.1% vs 63.2%, P < 0.05). However, there were no statistically significant differences in the N-cadherin expression between the patients with serum PSA < 20 microg/L and those with serum PSA > or = 20 microg/L (P > 0.05), nor in the expressions of E-cadherin and N-cadherin between the patients aged > or = 70 years and those aged < 70 years (P > 0.05).

The expressions of E-cadherin and N-cadherin are significantly different between high-risk prostate cancer and low- and medium-risk prostate cancer, which suggests that both may correlate with the invasion and metastasis of prostate cancer as well as with the serum PSA level and Gleason score of the patients.