The Hedgehog (Hh) signaling pathway was first identified in the common fruit fly. It is a highly conserved evolutionary pathway of signal transmission from the cell membrane to the nucleus. The Hh signaling pathway plays an important role in the embryonic development. It exerts its biological effects through a signaling cascade that culminates in a change of balance between activator and repressor forms of glioma-associated oncogene (Gli) transcription factors. The components of the Hh signaling pathway involved in the signaling transfer to the Gli transcription factors include Hedgehog ligands (Sonic Hh [SHh], Indian Hh [IHh], and Desert Hh [DHh]), Patched receptor (Ptch1, Ptch2), Smoothened receptor (Smo), Suppressor of fused homolog (Sufu), kinesin protein Kif7, protein kinase A (PKA), and cyclic adenosine monophosphate (cAMP). The activator form of Gli travels to the nucleus and stimulates the transcription of the target genes by binding to their promoters. The main target genes of the Hh signaling pathway are PTCH1, PTCH2, and GLI1. Deregulation of the Hh signaling pathway is associated with developmental anomalies and cancer, including Gorlin syndrome, and sporadic cancers, such as basal cell carcinoma, medulloblastoma, pancreatic, breast, colon, ovarian, and small-cell lung carcinomas. The aberrant activation of the Hh signaling pathway is caused by mutations in the related genes (ligand-independent signaling) or by the excessive expression of the Hh signaling molecules (ligand-dependent signaling – autocrine or paracrine). Several Hh signaling pathway inhibitors, such as vismodegib and sonidegib, have been developed for cancer treatment. These drugs are regarded as promising cancer therapies, especially for patients with refractory/advanced cancers.

Objective: Since Wnt signaling pathway plays a pivotal role in the placental development, we explored the expression of its negative regulators, SFRP1 and SFRP3 proteins in placentas from pathological pregnancies and compared their levels with those in healthy placentas. Methods: Placentas (n = 79) were stained for SFRP1, and SFRP3 proteins by immunohistochemistry and their expression levels were quantified by stereological variable of volume density (Vv, mm°). Results: Significantly higher expressions of SFRP1 and SFRP3 were found in all investigated groups of term and preterm pathologic placentas as well as in preterm control placentas in comparison with normal-term placentas. Conclusions: Our findings indicate the active involvement of negative Wnt regulators SFRP1/SFRP3 in placental development and important role in pathology of pregnancy.

To identify the involvement of Secreted Frizzled Related Protein 1 (SFRP1) promoter hypermethylation in different malignancy grades of astrocytoma and assess its association with beta-catenin, lymphoid-enhancer factor 1, and T-cell factor 1.Twenty-six ...

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 PTCH1 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 PTCH1 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 PTCH1 promoter methylation was only detected in HGSC. Further investigation is required to elucidate the possible mechanisms of PTCH1 activation in serous ovarian carcinomas.

Placental insufficiency is a common cause of intrauterine growth restriction (IUGR). It affects ~10% of pregnancies and increases fetal and neonatal morbidity and mortality. Although Wnt and Hh pathways are crucial for embryonic development and placentation, their role in the pathology of IUGR is still not sufficiently explored. The present study analyzed the expression of positive regulators of the Wnt pathway, WNT5A and β‑catenin, and the expression of the Hh pathway negative regulator suppressor of fused (SUFU). Immunohistochemical and reverse transcription‑quantitative PCR (RT‑qPCR) assays were performed on 34 IUGR and 18 placental tissue samples from physiologic singleton‑term pregnancies. Epigenetic mechanisms of SUFU gene regulation were also investigated by methylation‑specific PCR analysis of its promoter and RT‑qPCR analysis of miR‑214‑3p and miR‑378a‑5p expression. WNT5A protein expression was higher in endothelial cells of placental villi from IUGR compared with control tissues. That was also the case for β‑catenin protein expression in trophoblasts and endothelial cells and SUFU protein expression in trophoblasts from IUGR placentas. The SUFU gene promoter remained unmethylated in all tissue samples, while miR‑214‑3p and miR‑378a‑5p were downregulated in IUGR. The present results suggested altered Wnt and Hh signaling in IUGR. DNA methylation did not appear to be a mechanism of SUFU regulation in the pathogenesis of IUGR, but its expression could be regulated by miRNA targeting.