However, they display opposite effects, circ/linVRK1 favors apoptosis whereas circ/linMAN1A2 stimulates cell migration, and only XL765 did not alter the ratio of other dangerous circ/linRNAs in MCF-7. In MDA-MB-231 cells, AMG511 and GSK1070916 decreased circGFRA1, as a good response to drugs. Furthermore, some circRNAs might be associated with specific mutated pathways, such as the PI3K/AKT in MCF-7 cells with circ/linHIPK3 correlating to cancer progression and drug-resistance, or NHEJ DNA repair pathway in TP-53 mutated MDA-MB-231 cells.
These data provide evidence that combination palbociclib+voxtalisib therapy is safe, efficacious, and increases CDK4/6i efficiency in both pretreated and naive PDX models of OS. These studies provide rationale for earlier therapeutic intervention in pediatric and AYA OS patients with CDK4/6 hyperactivation signatures.
Once tumor volumes reached ~100mm3, mice were randomized and based on dose-finding studies treated with 5-day cycles of daily treatment with the CDK4/6 inhibitor palbociclib (50 mg/kg) +/- the dual PI3K/mTOR inhibitor voxtalisib (50 mg/kg) for 6-8 weeks. This study is of great significance for it provides strong rationale for earlier therapeutic intervention with a combination therapy targeting CDK4/6 and PI3K/mTOR pathways in a subset of OS patients with CDK4/6 hyperactivation. This therapeutic strategy has the potential to minimize disease burden and enhance quality of life in both the un-pretreated and the pre-treated clinical setting.
Voxtalisib, is a specific, effective, and reversible dual inhibitor, which inhibits both pan-class I phosphoinositide 3-kinase (PI3K) and mechanistic target of rapamycin (mTOR). Finally, the pharmacokinetic profile of the analyte had been availably studied by the UPLC-MS/MS bio-analytical method after rats were treated by intragastric administration with voxtalisib (5 mg/kg). The results indicated that the UPLC-MS/MS technology can effectively and quickly quantify the analyte, and this method can also be used for the pharmacokinetic study of voxtalisib, which can provide reference for the optimization of clinical drug management in the later period.
Combination index and Bliss independence analyses indicated that inhibition of OS growth by exposure to CDK4/6i (Palbociclib or Abemaciclib) and PI3K/mTOR inhibitor (PI3K/mTORi-Voxtalisib or LY3023414) was additive-to-synergistic and lead to increased apoptosis at clinically relevant concentrations. Notably, Palbociclib + Voxtalisib was more efficacious than single-agent (p<0.05, Two-way ANOVA; Holm-Sidak). These data highlight the need to optimize CDK4/6i+PI3K/mTORi dosing schedules and provide evidence that Palbociclib + Voxtalisib therapy is safe, efficacious, and can decrease CDK4/6i resistance in aggressive PDX models of OS.
Our results demonstrate that the expression of uc.183, uc.110, and uc.84 T-UCRs is mutually exclusive with miR-221 and is engaged in the regulation of CDKN1B expression. In addition, tests with a set of anticancer drugs, including BYL719, AZD5363, AZD8055, AZD7762, and XL765, revealed the modulation of specific T-UCRs without alteration of miR-221 levels.
Furthermore, a in silico screening of druggable targets and compounds from CTRP and PRISM databases was performed, resulting in the identification of five target genes (HMMR, CCNB1, CDC25C, AURKA, and CENPE) and five agents (oligomycin A, panobinostat, (+)-JQ1, voxtalisib, and arcyriaflavin A), which might have therapeutic potential in treating high-risk breast cancer patients. Further in vitro evaluation confirmed that (+)-JQ1 had the best cancer cell selectivity and exerted its anti-breast cancer activity through CENPE. In conclusion, our study provided new insights into personalized prognostication and may inspire the integration of risk stratification and precision therapy.
We next assessed whether birinapant has a synergistic effect with commonly used anti-cancer drugs, including entinostat (class I histone deacetylase inhibitor), cisplatin, paclitaxel, voxtalisib (PI3K inhibitor), dasatinib (Src inhibitor), erlotinib (epidermal growth factor receptor inhibitor), and gemcitabine, in TNBC. Birinapant significantly enhanced the anti-tumor activity of gemcitabine in TNBC both in vitro and in xenograft mouse models through activation of the intrinsic apoptosis pathway via degradation of cIAP2 and XIAP, leading to apoptotic cell death. Our findings demonstrate the therapeutic potential of birinapant to enhance the anti-tumor efficacy of gemcitabine in TNBC by targeting the IAP family of proteins.
Here, we assessed whether birinapant synergizes with commonly used anti-cancer drugs, including entinostat (class I histone deacetylase inhibitor), cisplatin, paclitaxel, voxtalisib (PI3K inhibitor), dasatinib (Src inhibitor), everolimus (mTOR inhibitor), and gemcitabine, in triple-negative breast cancer (TNBC). Our findings demonstrate the therapeutic potential of birinapant for enhancing the anti-tumor efficacy of gemcitabine in TNBC by targeting the IAP family of proteins.