engleski

Hh-Gli signaling in tumors ; Hh-Gli activation and effects on cell cycle progression

Ovarian dermoid cysts (DC) or benign cystic teratomas are benign tumors descending from germinal cells. In approximately 80% of the cases, these lesions occur in young women (20 to 30 years of age) and represent 18% to 20% of benign ovarian tumors. They are also a characteristic feature of Gorlin syndrome patients. In most cases, dermoid cysts are unilateral, but they are bilateral in 10% to 15% of cases. Dermoid cysts can be composed of elements descending from all three of the germinal layers. We present an investigation of Hh-Gli signaling pathway in sporadic cases of ovarian dermoids not related to Gorlin syndrome. Previously, we have shown that methylation of Ptch promoter may contribute to pathway malfunctioning in these tumors. In this work we focus on primary cell cultures derived from human tumors. We developed primary cell cultures from ovarian dermoid tissue and propagated them in cell culture. Several different clone lines were developed from the same tumor sample. RNA was isolated and Real-Time PCR analysis was performed. Real-Time PCR demonstrated expression of the Hh-Gli pathway genes. This expression, although present in all clone lines, differs among them, confirming the heterogeneity of this tumor type. Some of the clone lines were additionally analyzed by immunofluorescent staining. Our results show difference in localization of some of Hh-Gli pathway proteins among the clone lines, and some of them show reactivity to cyclopamine treatment, on both mRNA and protein level. I.e. we have seen difference in localization of Ptch and Smo during cell cycle. For cell cycle analysis cells were treated with cyclopamine, tomatidine or Shh protein, stained with propidium iodide and analyzed by flow cytometry. In this way we have also demonstrated effect of cyclopamine treatment on cell cycle progression of these clone lines. Taken together, this data suggests Hh-Gli pathway involvement in tumorigenesis and cell cycle progression of ovarian dermoids. Since similar results were previously shown on ovarian carcinoma, we suggest Hh-Gli pathway aberration is an early event in transformation of ovarian cells in their progression towards malignancy.

Hh-Gli signaling; tumors; tumor suppressors

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