@article{article_1541453, title={Changes in Phosphorylation Levels of PKA, AKT(PKB) and PKC Targeted AKT Substrates Upon EGF Stimulation in Metastatic Breast Cancer Cells}, journal={Necmettin Erbakan Üniversitesi Fen ve Mühendislik Bilimleri Dergisi}, volume={7}, pages={48–55}, year={2025}, author={Özcan Türkmen, Merve and Pehlivanoğlu, Şebnem and Pehlivanoğlu, Suray}, keywords={PI3K/AKT Yolağı, AKT Substratı, PKA, PKB ve PKC inhibisyonu}, abstract={Protein kinase B (PKB/AKT) is a crucial regulator of the phosphatidylinositol 3-kinase (PI3K)/AKT signaling pathway, which regulates a wide range of physiological and pathological processes, including cell metabolism, growth, proliferation, and tumor invasion. The AKT enzyme is a serine/threonine kinase that can be activated by cellular stimuli such as EGF. Once activated, the AKT enzyme phosphorylates its target substrates by binding to the RxRxxS/T consensus sequence. Some AKT targets can be phosphorylated at similar residues by different serine/threonine kinases. Numerous studies on these substrates provide valuable insights into common molecules facilitating cross-talk between signaling pathways and the identification of new therapeutic targets. In this study, we aimed to identify novel molecules that target PKA, PKB (AKT), and PKC and mimic AKT substrate phosphorylation in EGF-stimulated MDA-MB-231 triple-negative metastatic breast cancer cells. Phosphorylation levels of AKT substrates were assessed using Western blot analysis. According to the results, the phosphorylation level of a 30 kDa phosphoprotein (pp30) varied in the presence of PKA, PKB, and PKC inhibitors, as well as upon EGF stimulation. As expected, phosphorylation levels of AKT substrates increased with EGF stimulation, while the inhibitors suppressed these phosphorylations. Interestingly, in the presence of the PKC inhibitor, the phosphorylation level of pp30 was found to be decreased compared to the control, despite EGF stimulation. This suggests that cellular regulation of pp30 by PKC might occur through the same region as AKT. Our methodology demonstrates the potential to identify new regulators that may play a role in the interaction between AKT and PKC signaling pathways. However, further studies are required to elucidate the specifics of this interaction.}, number={1}, publisher={Necmettin Erbakan Üniversitesi}