Activity of the downstream PI3K effector protein kinase B (PKB) was higher in SqCas than in AdCas and was correlated with PIK3CA copy number (r = 0.75), suggesting that these copy number increases contribute to activation of PI3K signaling in SqCas of the lung.
After SCC transformation, the absence of G45 domain in DeltaG45 cells was associated with deficient extracellular signal-regulated kinase and phosphotidylinositol 3-kinase (PI3K) pathway activation, impaired invasion, deficient metalloproteinase activity, and absent tumorgenicity in vivo.
The majority of OSCC cell lines showed an activation of PI3K/Akt signaling, and enforced expression of NDRG2 in HSC-3 cells decreased the level of phosphorylated Akt at Serine 473 (p-Akt).
Knockdown of PLC-γ1 or PIKE blocked EGF-induced activation of class Ia PI3K and protein kinase C-ζ and phosphorylation of nucleolin in the nucleus as well as EGF-induced SCC cell proliferation.
In silico screening of candidate therapeutic compounds using subtype-specific pathway components identified HDAC and PI3K inhibitors as potential treatments tailored to lung SqCC.
The aim of the study was to investigate how alterations in the PI3K pathway correlate with non-small cell lung cancer subtypes squamous cell carcinoma (SSC) and adenocarcinoma (ADCA).
Head and neck squamous cell carcinomas exhibit variable sensitivity to inhibitors of the PI3K/mTOR pathway, an important target of genomic alterations in this cancer type.
Moreover, blocking the whole PI3K-AKT-mTOR pathway with the PI3K/mTOR dual inhibitor BEZ235 also showed efficacy in treating this subtype of lung SqCC.
The activated pathway in lung ADC and SCC mainly focuses on MAPK and PI3K with different key genes of each, respectively, and the activated pathway of SCLC mainly focuses on JAK-STAT pathway.
Computational analysis indicated that miR-296-3p targeted PTEN, which regulates the phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway and PTEN is involved in the carcinogenesis of SCC. miR-296-3p directly regulated PTEN expression in head and neck cancer cells, with PTEN protein levels decreased in 4/19 the SCCs (21.0%), as compared with those in the IPs (76.4%).
Activation of phosphoinositide 3-kinase (PI3K)/pAKT(Ser473) frequently occurs in advanced HPV-positive oropharyngeal SCC and elevated pAKT(Ser473) levels represent a feature during progression of oropharyngeal SCC, indicating a critical role of the mammalian target of rapamycin (mTOR) complex.
mTORis do not significantly change the immunohistochemical expression of molecules upstream of the mTOR inhibition (pmTOR, PI3K, pAkt), in cutaneous SCC.
PI3K inhibitors such as PI-103, PI-828 and PX-866 may be developed as potential therapeutic agents for effective treatment of oral squamous cell carcinoma (OSCC) patients, associated with activated PI3K/Akt pathway.