Buparlisib

Approximately 5% to 10% of asthma patients are resistant to glucocorticoid therapy; however, the mechanisms by which this resistance develops remain unclear. The present study investigated whether and how mechanistic target of rapamycin (mTOR) is involved in the development of steroid resistance using in vitro and in vivo murine models. The interleukin (IL)-33/thymic stromal lymphopoietin (TSLP)/IL-7-induced growth of group 2 innate lymphoid cells (ILC2) in vitro was resistant to dexamethasone (DEX), but suppressed by everolimus, an mTOR inhibitor, in a concentration-dependent manner. The inhibition of ILC2 growth by the combination of DEX and everolimus was significantly stronger than that by everolimus monotherapy. The combination of the pan-class I phosphatidylinositide-3 kinase inhibitor, buparlisib and the pan-Akt inhibitor, capivasertib also attenuated the resistance of IL-33/TSLP/IL-7-exposed ILC2s to DEX. The expression of the antiapoptotic factor, B-cell lymphoma-extra large, induced by IL-33/TSLP/IL-7 in ILC2s was significantly reduced by everolimus. Additionally, everolimus effectively suppressed the IL-33/TSLP/IL-7-induced phosphorylation of glucocorticoid receptors (GR) at the Ser234 residue, which has been reported to cause GR dysfunction. In the steroid-resistant asthma mouse model in vivo, under treatment with everolimus, DEX inhibited the development of airway remodeling and increased the number of ILC2s in the lungs. The present results suggest that the phosphoinositide 3-kinase/protein kinase B/mTOR pathway plays an essential role in the development of steroid resistance in ILC2s and asthma pathogenesis through both the expression of B-cell lymphoma-extra large and phosphorylation of GR. Therefore, mTOR inhibitors have the potential to restore glucocorticoid sensitivity and, thus, exert steroid-sparing effects in severe asthma patients. SIGNIFICANCE STATEMENT: Approximately 5% to 10% of asthma patients exhibit resistance to steroid therapy, posing a major clinical challenge due to limited treatment options. This study demonstrates that activation of the phosphoinositide 3-kinase/protein kinase B/mechanistic target of rapamycin (mTOR) pathway induces steroid resistance in group 2 innate lymphoid cells. Targeting mTOR with everolimus restores steroid sensitivity, highlighting mTOR inhibition as a promising pharmacotherapy for steroid-resistant asthma.

The present study investigates the in-silico identification of novel phytochemical inhibitors from N. nucifera molecularly targeting the PI3K/Akt/mTOR signalling pathway as a breast cancer chemotherapeutic agent, especially to treat PIK3CA mutant tumours. Despite huge advancements, including the application of various complex intracellular signalling pathways in oncogenesis, breast cancer remains a menace, causing significant morbidity and mortality worldwide. The efficiency of the PI3K/Akt/mTOR pathway plays a substantial part in hormone receptor-positive (HR+/HER2-) HER2-negative breast cancers, where mutations of the PIK3CA gene lead to tumour progression and are associated with therapy resistance. This study employs a range of computational approaches, including molecular docking, ADMET (absorption, distribution, metabolism, and toxicity) prediction, molecular dynamics simulations, MM-PBSA binding energy calculations, and Quantum calculations, to identify potential phytochemical inhibitors from N. nucifera. Two lead compounds, Anonaine (CID_160597) and Dehydroaporheine (CID_161899), exhibited more binding abilities towards the PI3Kα protein than the reference inhibitor buparlisib. These compounds were further studied for pharmacokinetic profile, bioactivity and toxicity, and they showed a high Drug-Likeness score. Notably, MD simulations revealed conserved interactions of these lead compounds with the PI3Kα protein, which could be promising for breast cancer therapeutic applications. This research lays the groundwork for additional experimental confirmation and underscores the promise of N. nucifera products in creating effective alternative therapies against breast cancer. This research may contribute to advancing personalised medicine approaches in oncology, offering new avenues for targeted therapies in PIK3CA-mutant breast cancer.