Proteomic analysis reveals that PI3K/mTOR inhibition in HGS-OvCa patient-derived xenografts induces both pro-apoptotic and anti-apoptotic signaling responses that limit cell killing, but also primes cells for inhibitors of anti-apoptotic proteins.
In this study, we have investigated the expression profile of 22 genes involved in the PI3K-AKT pathway in 26 high-grade ovarian carcinomas (19 serous and 7 clear cell carcinomas).
The resultant activation of the PI3K pathway in both breast and ovarian cancers contributes to cell-cycle progression, decreased apoptosis, and increased metastatic capabilities.
To confirm these findings at the protein level, immunohistochemistry (IHC) for PIK3CA product p110α and p-Akt was performed on tissue microarrays from 522 independent serous ovarian cancers.
PIK3R3, the gene that encodes the PI3K regulatory subunit p55γ, is over-expressed in glioblastoma and ovarian cancers, but its expression in gastric cancer (GC) is not known.
Taken together, these data suggest that PTEN over-expression may represent a novel therapeutic approach for chemoresistant human ovarian cancer and that this may involve a p53-mediated apoptotic cascade independent of the PI3K/Akt pathway.
Dysregulation of the phosphoinositide 3-kinase/mammalian target of rapamycin (PI3K/mTOR) and RAS/extracellular signal-regulated kinase (ERK) pathways is common in ovarian cancer, providing potential new targets for 2nd line therapy.
Here we identified the molecular mechanism that limits the efficacy of the beta-sparing PI3Ki, Taselisib (GDC0032), in PIK3CA-mutated OC cell lines (IGROV1 and OAW42) that acquired resistance to GDC0032.
PIK3CA, a catalytic subunit of PI3-kinase, is known to be activated in ovarian clear cell carcinoma (CCC), which is categorized as type I ovarian cancer.
We found no evidence of disease association for SNPs in BRAF, KRAS, ERBB2 and PIK3CA when OC was considered as a single disease phenotype; but after stratification by histological subtype, we found borderline evidence of association for SNPs in KRAS and BRAF with mucinous OC and in ERBB2 and PIK3CA with endometrioid OC.
The PI3K/AKT/mTOR signaling pathway is considered as a promising therapeutic target in the treatment of ovarian cancer (OC); however, inhibition of this pathway only exhibited moderate clinical efficacy when tested clinically.
We assayed a number of food phytochemicals with reported PI3K inhibitory ability to identify candidates that can influence CDDP treatment outcomes in chemoresistant OVCA cell lines.
We also found that an activating (E545K) Pik3ca mutation, unlike Pten inactivation or Pik3caH1047R mutation, cannot cooperate with Arid1a loss to promote ovarian cancer development in the mouse.
Notably, reduced expression of miRNA‑21 replicated the effect of celastrol on OVCAR3 cells and inhibited the PI3K/p‑Akt‑NF‑κB signaling pathway in an in vitro model of ovarian carcinoma.