The Significance Of PSCA Expression In Invasive Micropapillary Carcinoma Of The Breast

ObjectiveStudy the expression of prostate stem cell antigen (PSCA) protein and the association with clinicopathologic feature in invasive micropapillary carcinoma of the breast (IMPC).And we focused our attention on the epigenetics about the PSCA gene promoter to investigate the mechanism of lymph node metastasis of IMPC at mRNA.MethodsThe expression of PSCA protein was analyzed by immunohistochemistry in 66 cases of IMPC,67 cases of invasive ductal carcinoma of no special type (IDC-NOS). The association between PSCA expression and clinicopathologic parameters in IMPC was analyzed. RT-PCR was used to detect PSCA mRNA in 10 cases of paired primary IMPC and 10 cases of paired primary IDC-NOS tissue and normal breast tissue, each from the same subject.Results1. Lymph node metastasis rate of IMPC was much higher than IDC-NOS (Z=-4.927, P=0.000).2. The expression of PSCA protein was higher in IMPC comparing to that of IDC-NOS (χ2=5.063, P=0.024).3. In IMPC, the expression of PSCA was correlated with lymph nodes metastasis (P=0.039).4. The expression of PSCA is higher in IMPC and IDC-NOS than in normal breast tissue (P＜0.001).5. The PSCA mRNA was expression in all primary IMPC (10/10,100%) and was significantly higher than in paired normal breast tissue from the same patient (10/10,100%).6. The PSCA mRNA was expression in 8 cases IDC-NOS tissue (8/10,80%) and was higher in 6 cases IDC-NOS tissue than in paired normal breast tissue from the same patient (6/10,60%). 7. The mRNA relative expression intensity of PSCA gene was significantly higher in primary IMPC tissue than in IDC-NOS tissue (P<0.001).Conclusion1. PSCA might play an important role in lymph node metastasis in IMPC and might be a promoter of the mechanism of lymph node metastasis of IMPC.2. PSCA is a novel tumor marker for breast cancer that has potential diagnostic and therapeutic implications.