Expression and significance of differentially expressed protein endoplasmic reticulum aminopeptidase 1 in ovarian carcinoma with lymph node metastasis

Abstract

To detect the genetic transcription and protein expression level of endoplasmic reticulum aminopeptidase 1 (ERAP1) in human ovarian cancer cells and tissue and study their relationship with directional lymphatic metastasis. Real-time fluorescent quantitative PCR and western blot were used to determine the expressions of ERAP1 gene and protein in the human ovarian cancer cell lines between non-directional (SKOV3) and directional highly lymphatic metastasis (SKOV3-pm2, SKOV3-pm3, SKOV3-pm4). Immunohistochemistry method was used to further validate the ERAP1 expressions of the transplanted ovarian tumor primarily focus and the lesions of lymph node metastasis from nude mice and the human ovarian cancer primarily focus and the lesions of lymph node metastasis. The expression level of ERAP1 gene and protein were down-regulated in SKOV3, SKOV3-pm2, SKOV3-pm3, SKOV3-pm4 cell sublines (0.118 ± 0.012, 0.031 ± 0.003, 0.028 ± 0.003, 0.016 ± 0.005; 0.91 ± 0.33, 0.09 ± 0.03, 0.10 ± 0.04, 0.05 ± 0.04; respectively), and the level of ERAP1 in SKOV3 cell was higher than those in the other three kinds of cell lines (P < 0.05). The results showed that there were significant declining trend of expression of ERAP1 in the human ovarian cancer cell lines between non-directional and directional highly lymphatic metastasis; the transplanted ovarian tumor primarily focus and the metastasis lesions of lymph node from nude mice (143 ± 22 vs. 97 ± 12, P < 0.05), the primarily focus (184 ± 14) and the lesions of lymph node metastasis from human ovarian tumors (P < 0.05). The absence or down-regulated expression of ERAP1 is closely related to the metastasis and invasion of lymph node in ovarian carcinoma.