The results suggest that PIK3CA mutations are a late event and uncommon in the progression of malignant tumors, but it appears that they facilitate carcinogenesis in older women.
Oncogenic mutations in the PIK3CA gene, which codes for the catalytic subunit, have been identified in various malignancies and activate the PI3K/AKT/mTOR pathway, which is a critical driver of tumorigenesis.
Using in situ genetic lineage tracing and limiting dilution transplantation, we have unravelled the potential of PIK3CA(H1047R), one of the most frequent mutations occurring in human breast cancer, to induce multipotency during tumorigenesis in the mammary gland.
Genetic alterations are common in the PI3K/Akt pathway in thyroid cancer and play a fundamental role in the tumorigenesis and progression of this cancer.
These results suggest that PIK3CA mutations in HNSCC are likely to be oncogenic and may significantly contribute to HNSCC carcinogenesis and pave attractive target for therapeutic prevention.
PI3K pathway mutation is prominent in proximal colon cancers, with PIK3CA exon 20 and PTEN mutations associated with features of the sessile-serrated pathway (MSI-H/CIMP-H/BRAF(mut)), and PIK3CA exon 9 (and to a lesser extent exon 20) mutation associated with features of the traditional serrated pathway (CIMP-L/KRAS(mut)) of tumorigenesis.
Our findings indicate that PIK3CA mutations are a common event that can occur early in bladder carcinogenesis and support the notion that papillary and muscle-invasive tumors arise through different molecular pathways.
Activating mutations in the catalytic subunit of Phosphatidylinositol (3,4,5)-trisphosphate kinase (PI3K), encoded by the <i>Pik3ca</i> gene, are detected in approximately 20% of human anal cancers.<b>Experimental Design:</b> We asked if common activating mutations in <i>Pik3ca</i> contribute to anal carcinogenesis using an established mouse model for anal carcinogenesis in which mice are topically treated with the chemical carcinogen 7,12-Dimethylbenz(a)anthracene (DMBA).
Given the crucial roles of PIK3CA mutation and LINE-1 methylation levels, our findings might provide new insights into the biological mechanisms of ESCC tumorigenesis and progression.
The current data show that PIK3CA mutations appear to play an important role in carcinogenesis and tumor aggressiveness in EBV-GC, and also support the concept that exon 9 mutation of PIK3CA is a prognostic indicator for predicting patient outcomes and a rationale for therapeutic targeting in EBV-GC.
Specifically, p110alpha is essential for the signaling and growth of tumors driven by PIK3CA mutations and/or oncogenic RTKs/Ras, whereas p110beta is the major isoform in mediating PTEN-deficient tumorigenesis.
PIK3CA mutations in the helical binding domain and the catalytic subunit of the protein have been associated with tumorigenesis and treatment resistance in various malignancies.
To better understand the role of mutant PIK3CA in the initiation or progression of tumorigenesis, we generated mice in which a PIK3CA mutation commonly detected in human cancers (the H1047R mutation) could be conditionally knocked into the endogenous Pik3ca locus.
These findings show that mutated PI3K may be involved in the NPC tumorigenesis but does not affect patient's prognosis, suggesting that PI3K is a potential target in NPC for targeted therapeutics using specific kinase inhibitors.