Abstract: Objective · To explore the relationship between the of C2 calcium dependent domain containing protein 3 (C2CD3) in ovarian cancer and clinicopathological parameters, and its effect on the proliferation and invasion of ovarian cancer SKOV3 cells and possible mechanisms. Methods · The of C2CD3 protein in ovarian tissue was detectedimmunohistochemistry. The proliferation, migration and invasion abilities of SKOV3 cells were detectedEdU assay, wound healing assay and Transwell assay respectively. Western blotting was performed to investigate the of C2CD3, Shh, Ptch1, Smo and Gli1 proteins. Results · C2CD3 protein was located in cytoplasm in ovarian cancer. C2CD3 was highly expressed in ovarian cancer compared to normal ovarian tissue. C2CD3 immunostaining was significantly higher in tumor samples in advanced stages (stage Ⅲ / Ⅳ ) than in early stages (stage Ⅰ/ Ⅱ ). The staining intensity was significantly correlated with the grade (grade3 vs. grade1+2). The association between C2CD3 and age (or tumor type) was not significant. Inhibition of C2CD3 gene significantly weakened the proliferation, invasion and migration abilities of SKOV3 cells, and the of Shh, Ptch1, Smo and Gli1 proteins was significantly decreased. Conclusion · The of C2CD3 protein is increased in ovarian cancer tissues. Inhibition of C2CD3 gene weakens the proliferation, invasion and migration capacities of ovarian cancer SKOV3 cells, which may be related to the inhibition of Shh, Ptch1, Smo and Gli1 proteins in Hedgehog pathway.

Key words: C2 calcium dependent domain containing protein 3 (C2CD3), ovarian cancer, Hedgehog pathway, SKOV3 cells, invasion, migration