Expression of AP-2γ in placentas of patients with preeclampsia and of smokers

The biological characteristics of transcription factors AP-2α and AP-2γ and their importance in various types of cancers

The Activator Protein 2 (AP-2) transcription factor (TF) family is vital for the regulation of gene expression during early development as well as carcinogenesis process. The review focusses on the AP-2α and AP-2γ proteins and their dualistic regulation of gene expression in the process of carcinogenesis. Both AP-2α and AP-2γ influence a wide range of physiological or pathological processes by regulating different pathways and interacting with diverse molecules, i.e. other proteins, long non-coding RNAs (lncRNA) or miRNAs. This review summarizes the newest information about the biology of two, AP-2α and AP-2γ, TFs in the carcinogenesis process. We emphasize that these two proteins could have either oncogenic or suppressive characteristics depending on the type of cancer tissue or their interaction with specific molecules. They have also been found to contribute to resistance and sensitivity to chemotherapy in oncological patients. A better understanding of molecular network of AP-2 factors and other molecules may clarify the atypical molecular mechanisms occurring during carcinogenesis, and may assist in the recognition of new diagnostic biomarkers.

GNG7 silencing promotes the proliferation and differentiation of placental cytotrophoblasts in preeclampsia rats through activation of the mTOR signaling pathway

Preeclampsia (PE) is a pathological condition that manifests during pregnancy as the occurrence of an abnormal urine protein level and increased blood pressure due to inadequate cytotrophoblast invasion. To elucidate the mechanism underlying PE, the present study primarily focused on the regulatory effects and mechanism of the G protein γ 7 (GNG7) on placental cytotrophoblasts in a rat PE model. Initially, the PE model was established with 45 specific pathogen‑free Sprague‑Dawley rats (30 females and 15 males). The expression patterns of GNG7, 4E‑binding protein 1 (4E‑BP1), phosphoprotein 70 ribosomal protein S6 kinase (p70S6K) and mammalian target of rapamycin (mTOR) were examined in the PE rats. Placental cytotrophoblasts isolated from normal and PE rats were treated with a small interfering RNA against GNG7, mTOR signaling pathway activator (HIV‑1 Tat) or inhibitor (rapamycin). Following treatment, cell proliferation, differentiation and apoptosis were evaluated, and mTOR signaling pathway‑related factors (4E‑BP1, p70S6K and mTOR), cell proliferation‑related factors (vascular endothelial growth factor and transforming growth factor‑β1), differentiation‑related factors [activator protein‑2 (AP‑2)α and AP‑2γ], and apoptosis‑related factors [B‑cell lymphoma 2 (Bcl‑2) and Bcl‑2‑associated X protein] were determined. Finally, soluble fms‑like tyrosine kinase 1 (sFlt‑1) and soluble endoglin (sEng) levels were measured via enzyme‑linked immunosorbent assay. Initially, the mTOR signaling pathway was inactivated in the placental tissues and cytotrophoblasts in the PE rats. Silencing GNG7 reduced the levels of sFlt‑1 and sEng and activated the mTOR signaling pathway. Silencing of GNG7 or activation of the mTOR signaling pathway enhanced cell proliferation and differentiation, but inhibited the apoptosis of placental cytotrophoblasts in the PE rats. Taken together, the results showed that GNG7 silencing repressed apoptosis and enhanced the proliferation and differentiation of placental cytotrophoblasts in PE rats through activation of the mTOR signaling pathway.