Akt Inhibitor Research Articles

Randomised open-label phase II study of induction standard of care fulvestrant and CDK4/6 inhibition with addition of ipatasertib in metastatic ER+/HER2- breast cancer patients without circulating tumour (ct) DNA suppression (FAIM).

TPS1111 Background: The combination of fulvestrant and one of the three approved CDK4/6 inhibitors (i) is the standard of care for patients with ER+/HER2 metastatic breast cancer progressing on first-line endocrine therapy, or relapsing on or within a year of completing adjuvant endocrine therapy. AKT inhibition combined with fulvestrant has recently demonstrated clinically important activity in patients with advanced ER+/HER2- breast cancer progressing on first-line CDK4/6i plus an AI. Monitoring ctDNA dynamics has potential utility as an early response evaluation tool: Lack of suppression of ctDNA at day 15 in patients treated with palbociclib and fulvestrant in the PALOMA-3 trial was predictive for shorter PFS. We designed FAIM to establish whether the addition of the AKT inhibitor, ipatasertib, improves PFS in patients with poor ctDNA suppression during cycle 1 of fulvestrant and CDK4/6i. Methods: FAIM is a phase 2 multi-centre, randomised, open-label superiority trial in patients with ER+/HER2- advanced breast cancer, recruiting at centres in the UK. Patients will undergo ctDNA testing at days 1 and 15 of cycle 1 fulvestrant and CDK4/6 inhibitor. Eligible patients must be aged ≥18, have ER+ (≥1% or Allred score 3/8 or greater) and HER2- advanced breast cancer, measurable disease or assessable bone disease (RECIST 1.1), adequate organ function, fasting glucose ≤150mg/dL and HbA1c ≤7.5% and be eligible for NHS treatment with fulvestrant and CDK4/6i. Patients with diabetes requiring insulin, significant cardiac disease, a history of pneumonitis, or prior exposure to CDK4/6i are excluded. The FoundationOne Liquid CDx assay will be used for ctDNA analysis, a pan-cancer, tumour-agnostic liquid biopsy test that uses error-corrected next-generation sequencing. Patients with poor ctDNA suppression at day 15 will be eligible for the randomised (minimisation) study. Up to 483 patients starting fulvestrant andCDK4/6i will enroll for ctDNA screening to allow 174 patients to enter the randomised study. The primary endpoint of the study is to compare PFS in patients randomised to palbociclib/fulvestrant +/- ipatasertib. Secondary endpoints include safety, overall survival and overall response rate in all randomised patients and PFS in the sub-group of patients with alterations in the PIK3CA/AKT1/PTEN pathway. One hundred patients with ctDNA suppression at day 15, and up to 50 patients with no detectable ctDNA at day 1, will form additional control groups for exploratory outcome comparison to patients with poor ctDNA suppression. Enrolment began in December 2022 and is anticipated to continue for 2 years (NCT04920708). Clinical trial information: NCT04920708 .

Capivasertib in Hormone Receptor–Positive Advanced Breast Cancer

BackgroundAKT pathway activation is implicated in endocrine-therapy resistance. Data on the efficacy and safety of the AKT inhibitor capivasertib, as an addition to fulvestrant therapy, in patients with hormone receptor–positive advanced breast cancer are limited.MethodsIn a phase 3, randomized, double-blind trial, we enrolled eligible pre-, peri-, and postmenopausal women and men with hormone receptor–positive, human epidermal growth factor receptor 2–negative advanced breast cancer who had had a relapse or disease progression during or after treatment with an aromatase inhibitor, with or without previous cyclin-dependent kinase 4 and 6 (CDK4/6) inhibitor therapy. Patients were randomly assigned in a 1:1 ratio to receive capivasertib plus fulvestrant or placebo plus fulvestrant. The dual primary end point was investigator-assessed progression-free survival assessed both in the overall population and among patients with AKT pathway–altered (PIK3CA, AKT1, or PTEN) tumors. Safety was assessed.ResultsOverall, 708 patients underwent randomization; 289 patients (40.8%) had AKT pathway alterations, and 489 (69.1%) had received a CDK4/6 inhibitor previously for advanced breast cancer. In the overall population, the median progression-free survival was 7.2 months in the capivasertib–fulvestrant group, as compared with 3.6 months in the placebo–fulvestrant group (hazard ratio for progression or death, 0.60; 95% confidence interval [CI], 0.51 to 0.71; P<0.001). In the AKT pathway–altered population, the median progression-free survival was 7.3 months in the capivasertib–fulvestrant group, as compared with 3.1 months in the placebo–fulvestrant group (hazard ratio, 0.50; 95% CI, 0.38 to 0.65; P<0.001). The most frequent adverse events of grade 3 or higher in patients receiving capivasertib–fulvestrant were rash (in 12.1% of patients, vs. in 0.3% of those receiving placebo–fulvestrant) and diarrhea (in 9.3% vs. 0.3%). Adverse events leading to discontinuation were reported in 13.0% of the patients receiving capivasertib and in 2.3% of those receiving placebo.ConclusionsCapivasertib–fulvestrant therapy resulted in significantly longer progression-free survival than treatment with fulvestrant alone among patients with hormone receptor–positive advanced breast cancer whose disease had progressed during or after previous aromatase inhibitor therapy with or without a CDK4/6 inhibitor. (Funded by AstraZeneca and the National Cancer Institute; CAPItello-291 ClinicalTrials.gov number, NCT04305496.)

A randomized phase 2 non-inferiority trial of (Z)-endoxifen and exemestane + goserelin as neoadjuvant treatment for premenopausal women with ER+/HER2- breast cancer (EVANGELINE).

TPS633 Background: Ovarian function suppression (OFS) when combined with tamoxifen or an aromatase inhibitor is the standard of care for premenopausal estrogen receptor positive (ER+) human epidermal growth factor receptor 2 negative (HER2-) breast cancer (BC) based on SOFT (Francis 2022) and TEXT (Pagani 2022) clinical trials and confirmed in a metanalysis (EBCTCG 2022). However, estrogen deprivation in premenopausal women is associated with significant morbidity and up to 40% of premenopausal women with ER+/HER2- BC are intolerant of OFS. For these women, tamoxifen monotherapy is the only FDA approved option. Therefore, there is substantial room to improve endocrine therapy for premenopausal women with ER+/HER2- BC. (Z)-endoxifen is one of the most active anti-estrogen tamoxifen metabolites, with preclinical data demonstrating superiority to tamoxifen and letrozole in aromatase expressing xenograft models and evidence for antitumor activity in early phase clinical trials in patients with prior progression on endocrine therapy including tamoxifen. In addition to its ability to potently block ERa, (Z)-endoxifen at clinically achievable concentrations inhibits protein kinase C beta 1 (PKCβ1), resulting in downstream AKT inhibition and apoptosis. It is hypothesized that (Z)-endoxifen, when delivered as monotherapy at doses that dually target both ERα and PKCβ1, will potently inhibit BC proliferation while obviating the need for OFS in premenopausal women. If successful, this innovative approach could spare women with endocrine sensitive BC from the side effects of OFS. Methods: To further study (Z)-endoxifen in premenopausal women, a multicenter study in the United States, with possible expansion to other countries was designed (EVANGELINE; NCT05607004). This is a Phase 2, open-label, randomized, neoadjuvant study in premenopausal women with Stage IIA or IIB ER+/HER2- BC. Subjects are randomized 1:1 to either exemestane plus goserelin or (Z)-endoxifen. The primary objective is to determine whether the endocrine sensitive disease (ESD) rate (defined as Ki-67 ≤ 10% after 4 weeks of neoadjuvant therapy) with (Z)-endoxifen is non-inferior to exemestane plus goserelin. Subjects will be enrolled with the intent of surgical treatment in the involved breast(s) after completing 6 months of neoadjuvant treatment. Safety, tolerability, response rates and surgical outcomes will be assessed. Disease progression will be monitored throughout study participation. Paired tumor biopsies and blood sampling will allow for a robust biomarker evaluation. Prior to initiating the Treatment Cohort (162 subjects), up to 12 subjects will be enrolled in a pharmacokinetic (PK) Run-in Cohort to identify the optimal dose for the Treatment Cohort. Enrolment in the PK Run-in cohort began in February 2023. Clinical trial information: NCT05607004 .

Neuroprotection of isookanin against MPTP-induced cell death of SH-SY5Y cells via BCL2/BAX and PI3K/AKT pathways.

Isookanin, an important antioxidant component in Coreopsis tinctoria Nutt., has shown remarkable hypolipidemic, hypoglycemic, and hypotensive effects. However, the neuroprotective effect of isookanin has not been reported yet. Here, the neuroprotective effects and relevant molecular mechanisms of isookanin are explored for the first time. The SH-SY5Y cells were exposed to neurotoxic H2O2, 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), and Aβ25-35, respectively. Cell viability and apoptosis were evaluated by MTT, lactate dehydrogenase (LDH), and TUNEL assays. Intercellular ROS and mitochondrial membrane potential were assessed by DCFH-DA and JC-1 assay. Western blot and qRT-PCR were used to explore the perturbed signaling at the gene and protein levels. Molecular docking analysis and in vitro assay were further applied to confirm potential target. Among the three in vitro models, isookanin showed the best neuroprotection against MPTP-induced damage. Isookanin attenuated the levels of LDH, intracellular ROS, and mitochondrial membrane potential. Isookanin upregulated phosphorylation of AKT and PI3K, and increased BCL2/BAX ratio. Isookanin possessed a powerful affinity toward AKT. Besides, the protective effects of isookanin disappeared when cells were co-treated with an AKT inhibitor (AZD5363). Isookanin regulated BCL2/BAX and PI3K/AKT pathways to reduce mitochondrial damage and cellular apoptosis. Isookanin may be a new protector for neurodegenerative diseases.

Akt2 deficiency alleviates oxidative stress in the heart and liver via up-regulating SIRT6 during high-fat diet-induced obesity.

The present study aims to investigate the role of AKT2 in the pathogenesis of hepatic and cardiac lipotoxicity induced by lipid overload-induced obesity and identify its downstream targets. WT and Akt2 KO mice were fed either normal diet, or high-fat diet (HFD) to induce obesity model in vivo. Human hepatic cell line (L02 cells) and neonatal rat cardiomyocytes (NRCMs) were used as in vitro models. We observed that during HFD-induced obesity, Akt2 loss-of-function mitigated lipid accumulation and oxidative stress in the liver and heart tissue. Mechanistically, down-regulation of Akt2 promotes SIRT6 expression in L02 cells and NRCMs, the latter deacetylates SOD2, which promotes SOD2 activity and therefore alleviates oxidative stress-induced injury of hepatocytes and cardiomyocytes. Furthermore, we also proved that AKT2 inhibitor protects hepatocytes and cardiomyocytes from HFD-induced oxidative stress. Therefore, our work prove that AKT2 plays an important role in the regulation of obesity-induced lipid metabolic disorder in the liver and heart. Our study also indicates AKT2 inhibitor as a potential therapy for obesity-induced hepatic and cardiac injury.

Acquired AKT-inhibitor Resistance Is Mediated by ATP-binding Cassette Transporters in Endometrial Carcinoma.

Endometrial cancer is increasing in prevalence worldwide. It is treated with chemotherapy and radiotherapy, in addition to surgery, but the presence of treatment-resistant tumor cells remains a barrier to effective tumor control. The purpose of this study was to develop drug-resistant cell lines using triciribine, an AKT inhibitor, and investigate the mechanism of acquired resistance. Triciribine sensitivity assays were performed using Cell Counting Kit-8 (CCK-8) on eight endometrial cancer cell lines. The chosen cell lines were highly sensitive to chemotherapy and radiotherapy. A new triciribine-resistant cell line was established and found to be highly resistant to chemotherapy. Properties of the resistant cell line were identified using molecular and cell biological techniques including CCK-8 and quantitative PCR analysis. HEC-151 had the highest triciribine sensitivity (IC50 value of 0.7±0.1 μM) of the endometrial cancer cell lines tested. We established a triciribine-resistant cell line from HEC-151 by growing cells in the presence of increasing concentrations of triciribine up to 66.6 μM. The resistant HEC-151 cells changed to spindle-shaped morphology and importantly reduced triciribine sensitivity compared to the parental cell line. ABC transporters involved in drug efflux had significantly higher expression levels in ABCB1 (1.4±0.10 times higher), ABCC1 (11.4±0.22 times higher), and ABCC4 (4.5±0.42 times higher). In this study, we established a triciribine-resistant cell line from HEC-151 cells. Our data suggest that the mechanism of drug resistance in endometrial cancer cells is attributed to the increased expression of ABC transporters.

Combination of decaffeinated green coffee and decaffeinated green tea ameliorates cardiomyopathy through cardiotrophin-1-dependent expression regulation in a metabolic syndrome rat model: a proposed mechanism

BackgroundCardiovascular diseases (CVD) are the primary medical manifestation of metabolic syndrome (MetS). Hypoxia is also involved in the pathogenesis of CVD. Since dietary intervention significantly improved the physiological condition in MetS, the development of functional food to complement conventional medical therapy is essential. Among several standard consumable products, decaffeinated green tea (DGT) and decaffeinated green coffee (DGC) have excellent activity in managing MetS-induced CVD. However, the mechanism underlying their protective activity is poorly understood. This study aimed to understand the cardio-protective activity of DGT, DGC, and a combination of the two (DGT + DGC) in managing MetS-induced CVD in vivo and in silico.ResultsThe MetS condition led to the upregulation of Cardiotrophin-1 (CT-1), Signal Transducer and Activator of Transcription 3 (STAT3), GATA binding protein 4 (GATA4), and B-type Natriuretic Peptide (BNP) beyond the levels of the normal (N) group, while administration of DGT, DGC, and DGT + DGC significantly decreased the expression of those genes compared with the levels of the N group (p < 0.05). The computational analysis showed that the protective role of DGT, DGC, and DGT + DGC might be achieved through AKT1 inhibition by several bioactive components present in DGT and DGC. The analysis also defined the improvement in cardio-protective activity by combining DGT and DGC.ConclusionsThe administration of DGT, DGC, or DGT + DGC repaired cardiac dysfunction parameters through indirect regulation of the CT-1 signaling axis by inhibiting AKT1 activity.

Notopterol inhibits LPS-induced inflammation in BV-2 cells via AKT/Nrf2/HO-1 signaling axis

Accumulating research has indicated that inordinate activation of microglia releases inflammatory cytokines, damages neurons, and causes neuroinflammation, which eventually could lead to neurodegenerative diseases such as Parkinson's disease and Huntington’s disease, etc. Notopterol (NOT) has anti-inflammatory and anti-oxidant functions in boundary tissues, but the effects of NOT on neuroinflammation have not been covered. Therefore, this study attempts to investigate the effect of NOT on neuroinflammation and the underlying mechanisms. According to the findings, NOT dramatically decreased the expression of pro-inflammatory mediators (interleukin-6 (IL-6), inducible nitric-oxide synthase (iNOS), tumor necrosis factor-α (TNF-α), and Cyclooxygenase-2 (COX-2)) in LPS-exposed BV-2 cells. Western blot analysis revealed that NOT could promote the activation of AKT/Nrf2/HO-1 signaling pathway. Further studies have shown that anti-inflammatory property of NOT was inhibited by MK2206 (an AKT inhibitor), RA (an Nrf2 inhibitor), and SnPP IX (an HO-1 inhibitor). In addition, it was also discovered that NOT could weaken the damage of LPS to BV-2 cells and improve their survival rate. As a result, our results imply that NOT inhibits the inflammatory response of BV-2 cells through the AKT/Nrf2/HO-1 signaling axis and exerts a neuroprotective effect by inhibiting the activation of BV-2 cells.

Targeting the YAP/TAZ mechanotransducers in solid tumour therapeutics.

Targeting the YAP/TAZ mechanotransducers in solid tumour therapeutics.

Structure-based optimization of aminothiadiazole inhibitors of AKT

Structure-based optimization of aminothiadiazole inhibitors of AKT

Retraction: Akt inhibition enhanced the growth inhibition effect of low-dose heavy-ion radiation via the PI3K/Akt/P53 signaling pathway in C6 glioblastoma cells.

[This retracts the article DOI: 10.3389/fonc.2021.649176.].

Design, Synthesis, and Evaluation of a New Series of Hydrazones as Small-Molecule Akt Inhibitors for NSCLC Therapy.

In an endeavor to identify small molecules for the management of non-small-cell lung carcinoma, 10 new hydrazone derivatives (3a-j) were synthesized. MTT test was conducted to examine their cytotoxic activities against human lung adenocarcinoma (A549) and mouse embryonic fibroblast (L929) cells. Compounds 3a, 3e, 3g, and 3i were determined as selective antitumor agents on A549 cell line. Further studies were conducted to figure out their mode of action. Compounds 3a and 3g markedly induced apoptosis in A549 cells. However, both compounds did not show any significant inhibitory effect on Akt. On the other hand, in vitro experiments suggest that compounds 3e and 3i are potential anti-NSCLC agents acting through Akt inhibition. Furthermore, molecular docking studies revealed a unique binding mode for compound 3i (the strongest Akt inhibitor in this series), which interacts with both hinge region and acidic pocket of Akt2. However, it is understood that compounds 3a and 3g exert their cytotoxic and apoptotic effects on A549 cells via different pathway(s).

AKT inhibition sensitizes acute leukemia cells to S63845-induced apoptosis

ABSTRACTThe MCL1 inhibitors are undergoing clinical testing for multiple leukemia. However, because that MCL1 inhibition has on-target hematopoietic, hepatic and cardiac toxicities, there is substantial interest in finding agents can sensitize leukemia cells to the MCL1 inhibitors. Here we describe that the AKT inhibitors MK-2206 and Gsk690693 sensitize multiple leukemia cells to the MCL1 inhibitor S63845. Further experiments demonstrate that MK-2206 and Gsk690693 sensitize S63845 through the mitochondrial apoptosis pathway. Moreover, MK-2206 downregulates the anti-apoptotic protein BCLXL and induces the BH3-only pro-apoptotic protein BAD dephosphorylation and mitochondrial translocation. Knockdown of BAD significantly inhibits MK-2206-induced sensitization to S63845. Thus, our results suggest that MK-2206 sensitizes multiple leukemia cells to S63845-induced apoptosis, with the mechanisms involving BAD dephosphorylation and BCLXL downregulation.

RIPK1-dependent necroptosis promotes vasculogenic mimicry formation via eIF4E in triple-negative breast cancer

Necroptosis is a caspase-independent form of programmed cell death. Receptor interacting protein kinase 1 (RIPK1) is a key molecule in the initiation of necroptosis and the formation of the necrotic complex. Vasculogenic mimicry (VM) provides a blood supply to tumor cells that is not dependent on endothelial cells. However, the relationship between necroptosis and VM in triple-negative breast cancer (TNBC) is not fully understood. In this study, we found that RIPK1-dependent necroptosis promoted VM formation in TNBC. Knockdown of RIPK1 significantly suppressed the number of necroptotic cells and VM formation. Moreover, RIPK1 activated the p-AKT/eIF4E signaling pathway during necroptosis in TNBC. eIF4E was blocked by knockdown of RIPK1 or AKT inhibitors. Furthermore, we found that eIF4E promoted VM formation by promoting epithelial-mesenchymal transition (EMT) and the expression and activity of MMP2. In addition to its critical role in necroptosis-mediated VM, eIF4E was essential for VM formation. Knockdown of eIF4E significantly suppressed VM formation during necroptosis. Finally, through clinical significance, the results found that eIF4E expression in TNBC was positively correlated with the mesenchymal marker vimentin, the VM marker MMP2, and the necroptosis markers MLKL and AKT. In conclusion, RIPK1-dependent necroptosis promotes VM formation in TNBC. Necroptosis promotes VM formation by activating RIPK1/p-AKT/eIF4E signaling in TNBC. eIF4E promotes EMT and MMP2 expression and activity, leading to VM formation. Our study provides a rationale for necroptosis-mediated VM and also providing a potential therapeutic target for TNBC.

Diagnostic value and underlying mechanism of nasal nitric oxide in eosinophilic chronic rhinosinusitis with nasal polyps

PurposeNitric oxide (NO) is an important messenger molecule widely present in the human body. However, the role of nasal NO (nNO) in eosinophilic chronic rhinosinusitis with nasal polyps (Eos CRSwNP) remain unclear. This study aimed to investigate the diagnostic value and underlying mechanism of nNO in Eos CRSwNP. MethodsThe medical records of 84 non-Eos CRSwNP patients, 55 Eos CRSwNP patients, and 37 control subjects were retrospectively reviewed. The diagnostic value of nNO for Eos CRSwNP was assessed. The expression of inducible nitric oxide synthase (iNOS), endothelial nitric oxide synthase (eNOS), and tight junctions (TJs) components claudin-1, occludin, and ZO-1 was detected in the nasal polyps. Primary human nasal epithelial cells (HNECs) were co-treated with eNOS inhibitor (L-NAME) or Akt inhibitor (MK-2206), interleukin (IL)−13, and dexamethasone (Dex). The level of NO and the expression of TJs and Akt/eNOS pathways were examined. ResultsThe nNO levels of the CRSwNP group were significantly lower than those of the control group. Compared with the non-Eos CRSwNP group, the Eos CRSwNP group showed higher nNO level. The combination of nNO level, eosinophilic percentage, and posterior ethmoid score had a better predictive value for Eos CRSwNP (AUC = 0.855). The expression of iNOS, eNOS, and p-eNOS was higher in the CRSwNP groups than in the control group, and p-eNOS expression was higher in the Eos CRSwNP group than in the non-Eos CRSwNP group. The expression of TJs was lower in the Eos CRSwNP group than in the non-Eos CRSwNP and control group. IL-13 decreased TJ expression in HNECs, while Dex promoted Akt and eNOS phosphorylation, NO production and TJ expression. Furthermore, these effects of Dex were inhibited by L-NAME and MK-2206 in HNECs. ConclusionnNO may have a high diagnostic value in Eos CRSwNP, and Akt/eNOS pathway may promote the generation of NO to protect TJs. NO may have a potentially important role in the diagnosis and treatment of Eos CRSwNP.

CircZNF215 promotes tumor growth and metastasis through inactivation of the PTEN/AKT pathway in intrahepatic cholangiocarcinoma

BackgroundIncreasing evidence shows that circular RNAs (circRNAs), a novel class of noncoding RNAs, play a crucial role in the development of cancers, including intrahepatic cholangiocarcinoma (iCCA). Nevertheless, their functions and exact mechanisms in iCCA progression and metastasis are still unclear. Ipatasertib is a highly selective inhibitor of AKT that inhibits tumor growth by blocking the PI3K/AKT pathway. In addition, phosphatase and tensin homolog (PTEN) can also inhibit the activation of the PI3K/AKT pathway, but it is not clear whether the cZNF215-PRDX-PTEN axis plays a role in the antitumor activity of ipatasertib.MethodsWe identified a new circRNA (circZNF215, termed cZNF215) through high-throughput circRNA sequencing (circRNA-seq). In addition, RT‒qPCR, immunoblot assay, RNA pull-down assay, RNA immunoprecipitation (RIP) assay, and fluorescence in situ hybridization assay (FISH) were used to investigate the interaction of cZNF215 with peroxiredoxin 1 (PRDX1). Coimmunoprecipitation (Co-IP) assays and duolink in situ proximity ligation assays (PLAs) were conducted to analyze the effects of cZNF215 on the interaction between PRDX1 and PTEN. Finally, we tested the potential effects of cZNF215 on the antitumor activity of ipatasertib with in vivo experiments.ResultsWe found that cZNF215 expression was obviously upregulated in iCCA tissues with postoperative metastases and was correlated with iCCA metastasis and poor outcome in patients with iCCA. We further revealed that overexpression of cZNF215 promoted iCCA cell growth and metastasis in vitro and in vivo, while cZNF215 knockdown had the opposite effect. Mechanistic studies suggested that cZNF215 competitively interacted with PRDX1, which blocked the association between PRDX1 and PTEN, subsequently leading to oxidation-induced inactivation of the PTEN/AKT pathway and finally contributing to iCCA progression and metastasis. Additionally, we also revealed that silencing cZNF215 in iCCA cells had the potential to enhance the antitumor effect of ipatasertib.ConclusionsOur study demonstrates that cZNF215 facilitates iCCA progression and metastasis by regulating the PTEN/AKT pathway and may serve as a novel prognostic predictor in patients with iCCA.

Computational drug repurposing of Akt-1 allosteric inhibitors for non-small cell lung cancer

Non-small cell lung carcinomas (NSCLC) are the predominant form of lung malignancy and the reason for the highest number of cancer-related deaths. Widespread deregulation of Akt, a serine/threonine kinase, has been reported in NSCLC. Allosteric Akt inhibitors bind in the space separating the Pleckstrin homology (PH) and catalytic domains, typically with tryptophan residue (Trp-80). This could decrease the regulatory site phosphorylation by stabilizing the PH-in conformation. Hence, in this study, a computational investigation was undertaken to identify allosteric Akt-1 inhibitors from FDA-approved drugs. The molecules were docked at standard precision (SP) and extra-precision (XP), followed by Prime molecular mechanics—generalized Born surface area (MM-GBSA), and molecular dynamics (MD) simulations on selected hits. Post XP-docking, fourteen best hits were identified from a library of 2115 optimized FDA-approved compounds, demonstrating several beneficial interactions such as pi–pi stacking, pi-cation, direct, and water-bridged hydrogen bonds with the crucial residues (Trp-80 and Tyr-272) and several amino acid residues in the allosteric ligand-binding pocket of Akt-1. Subsequent MD simulations to verify the stability of chosen drugs to the Akt-1 allosteric site showed valganciclovir, dasatinib, indacaterol, and novobiocin to have high stability. Further, predictions for possible biological interactions were performed using computational tools such as ProTox-II, CLC-Pred, and PASSOnline. The shortlisted drugs open a new class of allosteric Akt-1 inhibitors for the therapy of NSCLC.

Downregulation of mTORC1 and Mcl-1 by lipid-oversupply contributes to islet β-cell apoptosis and dysfunction

Pancreatic β-cell apoptosis is a key feature of diabetes and can be induced by chronic exposure to saturated fatty acids (FAs). However, the underlying mechanisms remain poorly understood. We presently evaluated the role of Mcl-1 and mTOR in mice fed with high-fat-diet (HFD) and β-cells exposed to the overloaded palmitic acid (PA). Compared with normal-chow-diet (NCD)-fed mice, HFD group showed impaired glucose tolerance after two months. Along with the diabetes progression, pancreatic islets first became hypertrophic and then atrophic, the ratio of β-cell:α-cell increased in the islets of four months HFD-fed mice while decreased after six months. This process was accompanied by significantly increased β-cell apoptosis and AMPK activity, and decreased Mcl-1 expression and mTOR activity. Consistently, glucose-induced insulin secretion dropped. In terms of mechanism, PA with lipotoxic dose could activate AMPK, which in turn inhibited ERK-stimulated Mcl-1Thr163 phosphorylation. Meanwhile, AMPK blocked Akt activity to release Akt inhibition on GSK3β, followed by GSK3β-initiated Mcl-1Ser159 phosphorylation. The context of Mcl-1 phosphorylation finally led to its degradation by ubiquitination. Also, AMPK inhibited the activity of mTORC1, resulting in a lower level of Mcl-1. Suppression of mTORC1 activity and Mcl-1 expression positively related to β-cell failure. Alteration of Mcl-1 or mTOR expression rendered different tolerance of β-cell to different dose of PA. In conclusion, lipid oversupply-induced dual modulation of mTORC1 and Mcl-1 finally led to β-cell apoptosis and impaired insulin secretion. The study may help further understand the pathogenesis of β-cell dysfunction in case of dyslipidemia, and provide promising therapeutic targets for diabetes.

The activity and surface presence of organic cation/carnitine transporter OCTN2 (SLC22A5) in breast cancer cells depends on AKT kinase

l-carnitine is indispensable for transfer of fatty acids to mitochondria for the process of β-oxidation, a process, whose significance in cancer has drawn attention in recent years. In humans majority of carnitine is delivered by diet and enters the cell due to activity of solute carriers (SLCs), mainly by ubiquitously expressed organic cation/carnitine transporter (OCTN2/SLC22A5). In control and cancer human breast epithelial cell lines the major fraction of OCTN2 is present as a not matured non-glycosylated form. Studies on overexpressed OCTN2 demonstrated an exclusive interaction with SEC24C, as the cargo-recognizing subunit of coatomer II in transporter exit from endoplasmic reticulum. Co-transfection with SEC24C dominant negative mutant completely abolished presence of the mature form of OCTN2, pointing to a possibility of trafficking regulation. SEC24C was previously shown to be phosphorylated by serine/threonine kinase AKT, known to be activated in cancer. Further studies on breast cell lines showed that inhibition of AKT with MK-2206 in control and cancer lines decreased level of OCTN2 mature form. Proximity ligation assay showed that phosphorylation of OCTN2 on threonine was significantly abolished by AKT inhibition with MK-2206. Carnitine transport was positively correlated with the level of OCTN2 phosphorylated by AKT on threonine moiety. The observed regulation of OCTN2 by AKT places this kinase in the center of metabolic control. This points to both proteins, AKT and OCTN2, as druggable targets, in particular in a combination therapy of breast cancer.

Interleukin (IL)-17A in triple-negative breast cancer: a potent prognostic factor associated with intratumoral neutrophil infiltration.

Triple-negative breast cancer (TNBC) is characterized as highly immunogenic and lacks specific targeted therapies. Interleukin 17A (IL-17A) is a controversial cytokine and is known to have anti-tumor and pro-tumor roles depending on the tumor microenvironment. In addition, IL-17A has been recently implicated in the recruitments of neutrophil into tumor tissues. Although IL-17A is considered tumor-promoting in breast cancer, its significance in the possible regulation of neutrophil infiltration in TNBC is not clearly defined. We immunolocalized IL-17A, CD66b (neutrophil marker), and chemokine (C-X-C motif) ligand 1 (CXCL1, neutrophil chemoattractant) in 108 TNBC specimens and assessed their correlation among each other. The correlation between these markers and clinicopathological parameters was also assessed. We subsequently performed in vitro study to address the possible regulation of CXCL1 by IL-17A using TNBC cell lines, MDA-MB-231 and HCC-38. It was revealed that IL-17A correlated significantly with CXCL1 and CD66b, also CD66b with CXCL1. Furthermore, IL-17A was significantly associated with shorter disease-free and overall survival, especially in a high density CD66b group of patients. In vitro results revealed that IL-17A upregulated CXCL1 mRNA expression in a dose and time dependent manner, and this induction was significantly suppressed by an Akt inhibitor. IL-17A was considered to contribute to neutrophil infiltration by inducing CXCL1 in TNBC tissues and educating neutrophils to promote tumor progression. IL-17A might therefore serve as a potent prognostic factor in TNBC.