Department of Biology, School of Medicine, University of Zagreb, 10000 Zagreb, Croatia.
Institute of Biochemistry II, School of Medicine, Goethe University, D‑60590 Frankfurt am Main, Germany.
Int J Oncol. 2022 Dec;61(6). doi: 10.3892/ijo.2022.5435. Epub 2022 Oct 7.
The Hedgehog (Hh) signaling pathway is essential for normal embryonic development, while its hyperactivation in the adult organism is associated with the development of various cancers. The role of the Hh signaling pathway in ovarian cancer has not been sufficiently investigated. Therefore, the present study investigated the role of protein patched homolog 1 (PTCH1), a component of the Hh signaling pathway, and changes in the promoter methylation status of the corresponding gene in a cohort of low‑(LGSC) and high‑grade serous ovarian carcinomas (HGSC) and HGSC cell lines (OVCAR8 and OVSAHO). PTCH1 protein expression level was analyzed using immunohistochemistry in tissue samples and immunofluorescence and western blotting in cell lines. DNA methylation patterns of the gene were analyzed using methylation‑specific PCR. PTCH1 protein expression was significantly higher in HGSCs and LGSCs compared with controls (healthy ovaries and fallopian tubes). Similarly, ovarian cancer cell lines exhibited significantly higher PTCH1 protein expression compared with a normal fallopian tube non‑ciliated epithelial cell line (FNE1). PTCH1 protein fragments of different molecular weights were detected in all cell lines, indicating possible proteolytic cleavage of this protein, resulting in the generation of soluble N‑terminal fragments that are translocated to the nucleus. DNA methylation of the gene promoter was exclusively detected in a proportion of HGSC (13.5%) but did not correlate with protein expression. PTCH1 protein was highly expressed in serous ovarian carcinoma tissues and cell lines, while promoter methylation was only detected in HGSC. Further investigation is required to elucidate the possible mechanisms of PTCH1 activation in serous ovarian carcinomas.
Hedgehog（Hh）信号通路对于正常胚胎发育至关重要，而其在成年生物体中的过度激活与各种癌症的发展有关。Hh 信号通路在卵巢癌中的作用尚未得到充分研究。因此，本研究调查了 Hh 信号通路的组成部分蛋白 patched 同源物 1（PTCH1）以及相应基因启动子甲基化状态的改变在低级别浆液性卵巢癌（LGSC）和高级别浆液性卵巢癌（HGSC）和 HGSC 细胞系（OVCAR8 和 OVSAHO）中的作用。使用免疫组织化学在组织样本中以及免疫荧光和蛋白质印迹法在细胞系中分析 PTCH1 蛋白表达水平。使用甲基化特异性 PCR 分析基因的 DNA 甲基化模式。与对照（健康卵巢和输卵管）相比，HGSC 和 LGSC 中的 PTCH1 蛋白表达明显更高。同样，与正常输卵管非纤毛上皮细胞系（FNE1）相比，卵巢癌细胞系也表现出明显更高的 PTCH1 蛋白表达。在所有细胞系中均检测到不同分子量的 PTCH1 蛋白片段，表明该蛋白可能发生蛋白水解切割，从而产生可转移至细胞核的可溶性 N 端片段。仅在一部分 HGSC（13.5%）中检测到基因启动子的 DNA 甲基化，但与蛋白表达无关。PTCH1 蛋白在浆液性卵巢癌组织和细胞系中高度表达，而仅在 HGSC 中检测到基因启动子甲基化。需要进一步研究阐明浆液性卵巢癌中 PTCH1 激活的可能机制。
