Objective: To study the expression of retinoblastoma susceptibility gene(Rb) and minichromosome maintenance protein 2(MCM2) in primary prostate cancer(PCa) and its clinical significance.Methods: The expression of MCM2 protein and pRb were detected in 49 cases of PCa

20 cases of benign prostate hyperplasia(BPH)

10 cases of normal prostate tissues(NP) by EliVisionTM plus immunohistochemical staining.Results: The positive expression rate of pRb in PCa

BPH

NP were 44.90%

80% and 90% respectively.The expression level of pRb in PCa was significantly lower than that in BPH(P<0.05) and NP(P<0.05)

and was negatively correlated with pathological grades(P<0.05) and clinical stages(P<0.05) of PCa.The positive expression rate of MCM2 in PCa

BPH

NP were 67.35%

25% and 10% respectively

however

the expression level of MCM2 in PCa was significantly higher than that in BPH(P<0.05) and NP(P<0.05)

and was positively correlated with pathological grades(P<0.05) and clinical stages(P<0.05) of PCa.The expression level of MCM2 in PCa was negatively correlated with pRb(rs =-0.596

P <0.01).Conclusion: Rb might be involved in the occurrence and development of PCa.The determination of Rb and MCM2 can be an index for estimating the level of malignancy and prognosis of PCa.