Expression of lysophosphatidic acid receptors and local invasiveness and metastasis in Chinese pancreatic cancers.

BACKGROUND AND OBJECTIVES: The present study evaluated the potential role of lysophosphatidic acid receptors (lpars) in processes leading to local invasiveness and metastasis in Chinese pancreatic carcinoma. METHODS: Real-time reverse-transcriptase polymerase chain reaction and Western blot analysis were used to detect expression of lpars in tumour and adjacent non-tumour tissues from patients with surgically resected pancreatic carcinoma. Surgical specimens from 50 patients were examined for relative expression of each receptor's messenger rna (mrna) and protein. Findings were analyzed for correlations with tumour size, pathologic classification, clinical stage, and infiltration of capsule and lymphonodi. RESULTS: Increased levels of mrna of lpars (lpar1 ≈ lpar3 < lpar2) were found in the pancreatic cancer tissues examined. Low levels of transcripts for lpar1, lpar2, and lpar3 receptors were detectable in adjacent non-tumour tissues. The difference in lpar1 protein expression between tumour and adjacent non-tumour tissues does not seem significant, but the signals of lpar2 expression in pancreatic cancer tumour tissues were significantly amplified compared with those in adjacent non-tumour tissues. Tumour and adjacent non-tumour tissues both weakly expressed lpar3 protein with no statistical difference. However, expression of lpar1, lpar2, and lpar3 showed an obvious correlation with infiltration of capsule cells, surrounding lymphonodi, and specific histopathologic features. CONCLUSIONS: Lysophosphatidic acid receptor is a promising indicator for pancreatic cancer, and our findings suggested that lpar2 might be a potential target for clinical treatment of pancreatic cancer.