PAR-1 regulation of intracellular Ca²(+) mobilization in pulmonary giant cell carcinoma cell line PLA801D/PLA801C / 中华病理学杂志

<p><b>OBJECTIVES</b>To investigate molecular mechanisms of PAR-1 regulation on intracellular Ca²(+) mobilization in lung giant cell carcinoma cells in vitro and its involvement in tumor metastasis.</p><p><b>METHODS</b>Free intracellular Ca²(+) ([Ca²(+)]i) was measured in lung giant cell carcinoma PLA801C and PLA801D cells by confocal microscopy. Sense and anti-sense PAR-1 expression vectors were transfected into PLA801C (C+)and PLA801D(D-) cells, respectively. The effects of PAR-1 expression were investigated by thrombin and TRAP-induced mobilization of [Ca²(+)]i in the C+ and D-cells.</p><p><b>RESULTS</b>There were significant differences of the mean values of [Ca²(+)]i between PLA801D (59.55) and PLA801C cells (35.46, P < 0.01). The mean [Ca²(+)]i of C+ cells (45.77) was significantly higher than that of its control CV cells (35.46, P < 0.05), and the mean [Ca²(+)]i of D-cells (48.42) was significantly lower than that of its control DV cells (59.55, P < 0.05). The peaks of [Ca²(+)]i of C+ and CV cells were 48.19 ± 9.84 and 45.64 ± 9.87 (P < 0.05) respectively at 80 s and 100 s after thrombin treatment, but were 111.31 ± 25.00 and 52.93 ± 11.21 (P < 0.05) respectively at 60 s after TRAP treatment. The peaks of [Ca²(+)]i of D- and DV cells were 40.71 ± 5.89 and 61.07 ± 21.36 (P < 0.05) respectively at 60 s after thrombin treatment, but were 84.98 ± 11.23 and 102.58 ± 21.48 (P < 0.05) respectively at 40 s after TRAP treatment.</p><p><b>CONCLUSIONS</b>The high metastatic potential of PLA801D and PLA801C may be related to [Ca²(+)]i of the tumor cells. PAR-1 may play an important role in the metastasis of lung giant cell carcinoma cells by up-regulating the intracellular Ca²(+).</p>

Expression of PAR-1 in human lung carcinoma and its relationship with tumor metastatic potential / 中华病理学杂志

<p><b>OBJECTIVE</b>To explore the correlation between expression of PAR-1 and metastasis of human lung carcinoma.</p><p><b>METHODS</b>Expression levels of PAR-1 were examined in surgically resected lung carcinoma specimens and corresponding lymph nodes by RT-PCR and immunohistochemistry, combined with morphometric methodology and clinicopathologic profiles.</p><p><b>RESULTS</b>Strong PAR-1 staining was detected in the periphery of carcinoma nests, adenocarcinomatous emboli, foci of atypical adenomatous hyperplasia adjacent to the adenocarcinoma and atypical proliferation of duct epithelium of bronchial mucous glands. The expression rates of PAR-1 were 73.8% (59/80) and 63.9% (23/36) by immunohistochemistry and RT-PCR respectively. The percentage of PAR-1 protein expression cells was significantly higher in tumors with metastasis (85.7%, 48/56) than those without (45.8%, 11/24). Morphometric study demonstrated that there were significant differences of PAR-1 protein expression levels between tumors with metastatic and those without, primary and metastatic carcinomas, primary carcinomas and benign lung tissues adjacent to the carcinoma. No significant correlation was found between PAR-1 expression level and tumor size, histological types and tumor grades. The positive rate of PAR-1 mRNA expression in the metastatic group was significantly higher than that of the non-metastatic group (78.3%, 18/23 v.s. 38.5%, 5/13).</p><p><b>CONCLUSION</b>PAR-1 expression may play an important role in determining the malignant phenotypes of lung cancers and significantly contribute to their initiation, progression and metastasis.</p>