Design, synthesis, and biological evaluation of novel benzimidazole derivatives as anti-cervical cancer agents through PI3K/Akt/mTOR pathway and tubulin inhibition.

Phosphatidylinositol 3-kinase (PI3K) is one of the most attractive therapeutic targets for cervical cancer treatment. In this study, we designed and synthesized a series of benzimidazole derivatives and evaluated their anti-cervical cancer activity. Compound 4r exhibited strong antiproliferative activity in different cervical cancer cell lines HeLa, SiHa and Ca Ski, and relative lower cytotoxicity to normal hepatic and renal cell lines LO2 and HEK-293t (IC50 values were at 21.08 µM and 23.96 µM respectively). Its IC50 value was at 3.38 µM to the SiHa cells. Further mechanistic studies revealed that 4r induced apoptosis, arrested cell cycle in G2/M phase, suppressed PI3K/Akt/mTOR pathway and inhibit the polymerization of tubulin. Molecular docking study suggested that 4r formed key H-bonds action with PI3Kα (PDB ID:8EXU) and tubulin (PDB ID:1SA0). Zebrafish acute toxicity experiments showed that high concentrations of 4r did not cause death or malformation of zebrafish embryos. All these results demonstrated that 4r would be a promising lead candidate for further development of novel PI3K and tubulin dual inhibitors in cervical cancer treatment.

Akt Inhibitor Advancements: From Capivasertib Approval to Covalent-Allosteric Promises.

Akt kinase is vital in cell growth, survival, metabolism, and migration. Dysregulation of Akt signaling is implicated in cancer and metabolic disorders. In the context of cancer, overactive Akt promotes cell survival and proliferation. This has spurred extensive research into developing Akt inhibitors as potential therapeutic agents to disrupt aberrant Akt signaling. Akt inhibitors are classified into three main types: ATP-competitive, allosteric, and covalent-allosteric inhibitors (CAAIs). ATP-competitive inhibitors compete with ATP for binding to Akt, allosteric inhibitors interact with the Pleckstrin homology (PH) domain, and covalent-allosteric inhibitors form covalent bonds, making them more potent and selective. Notably, capivasertib (AZD5363), a potent ATP-competitive Akt inhibitor, received FDA approval in November 2023 for use in combination with the estrogen receptor degrader fulvestrant to treat breast cancer. Challenges remain, including improving selectivity, identifying biomarkers to tailor treatments, and enhancing therapeutic efficacy while minimizing adverse effects. Particularly covalent-allosteric inhibitors hold promise for future more effective and personalized treatments.

Targeting the PI3K/AKT signaling pathway in anticancer research: a recent update on inhibitor design and clinical trials (2020-2023).

INTRODUCTION: Recent years have witnessed great achievements in drug design and development targeting the phosphatidylinositol 3-kinase/protein kinase-B (PI3K/AKT) signaling pathway, a pathway central to cell growth and proliferation. The nearest neighbor protein-protein interaction networks for PI3K and AKT show the interplays between these target proteins which can be harnessed for drug discovery. In this review, we discuss the drug design and clinical development of inhibitors of PI3K/AKT in the past three years. We review in detail the structures, selectivity, efficacy, and combination therapy of 35 inhibitors targeting these proteins, classified based on the target proteins. Approaches to overcoming drug resistance and to minimizing toxicities are discussed. Future research directions for developing combinational therapy and PROTACs of PI3K and AKT inhibitors are also discussed. AREA COVERED: This review covers clinical trial reports and patent literature on inhibitors of PI3K and AKT published between 2020 and 2023. EXPERT OPINION: To address drug resistance and drug toxicity of inhibitors of PI3K and AKT, it is highly desirable to design and develop subtype-selective PI3K inhibitors or subtype-selective AKT1 inhibitors to minimize toxicity or to develop allosteric drugs that can form covalent bonds. The development of PROTACs of PI3Kα or AKT helps to reduce off-target toxicities.

Potential Anti-Gouty Arthritis of Citronella Essential Oil and Nutmeg Essential Oil through Reducing Oxidative Stress and Inhibiting PI3K/Akt/mTOR Activation-Induced NLRP3 Activity.

Citronella and Nutmeg are two common spices used for seasoning and medicinal purposes, both of which have significant economic value. This study aimed to investigate whether Citronella essential oil and Nutmeg essential oil (NEO) can ameliorate monosodium urate (MSU)-induced gouty arthritis in rats and the potential mechanisms. The results showed that CEO and NEO reduced swelling and redness at joint sites, inhibited neutrophil infiltration, and limited proinflammatory mediator secretion in mice with MSU-induced gouty arthritis. Based on the results of network pharmacology, molecular docking, and western blotting, CEO and NEO may exert anti-gouty arthritis effects by reducing the expression of reactive oxygen species and oxidative stress and downregulating the phosphorylation of the PI3K/AKT/mTOR signaling pathway, thereby inhibiting the production of the NLRP3 inflammasome and inhibiting the production of inflammatory cytokines. Therefore, these two essential oils show potential for use as adjuvant treatments for gouty arthritis in specific aromatherapy products or food seasonings.

Discovery of a nitroaromatic nannocystin with potent in vivo anticancer activity against colorectal cancer by targeting AKT1.

The development of targeted chemotherapeutic agents against colorectal cancer (CRC), one of the most common cancers with a high mortality rate, is in a constant need. Nannocystins are a family of myxobacterial secondary metabolites featuring a 21-membered depsipeptide ring. The in vitro anti-CRC activity of natural and synthetic nannocystins was well documented, but little is known about their in vivo efficacy and if positive, the underlying mechanism of action. In this study we synthesized a nitroaromatic nannocystin through improved preparation of a key fragment, and characterized its in vitro activity and in vivo efficacy against CRC. We first described the total synthesis of compounds 2-4 featuring Heck macrocyclization to forge their 21-membered macrocycle. In a panel of 7 cancer cell lines from different tissues, compound 4 inhibited the cell viability with IC values of 1-6 nM. In particular, compound 4 (1, 2, 4 nM) inhibited the proliferation of CRC cell lines (HCT8, HCT116 and LoVo) in both concentration and time dependent manners. Furthermore, compound 4 concentration-dependently inhibited the colony formation and migration of CRC cell lines. Moreover, compound 4 induced cell cycle arrest at sub-G1 phase, apoptosis and cellular senescence in CRC cell lines. In three patient-derived CRC organoids, compound 4 inhibited the PDO with IC values of 3.68, 28.93 and 11.81 nM, respectively. In a patient-derived xenograft mouse model, injection of compound 4 (4, 8 mg/kg, i.p.) every other day for 12 times dose-dependently inhibited the tumor growth without significant change in body weight. We conducted RNA-sequencing, molecular docking and cellular thermal shift assay to elucidate the anti-CRC mechanisms of compound 4, and revealed that it exerted its anti-CRC effect at least in part by targeting AKT1.

Methyl vinyl ketone and its analogs covalently modify PI3K and alter physiological functions by inhibiting PI3K signaling.

Reactive carbonyl species (RCS), which are abundant in the environment and are produced in vivo under stress, covalently bind to nucleophilic residues such as Cys in proteins. Disruption of protein function by RCS exposure is predicted to play a role in the development of various diseases such as cancer and metabolic disorders, but most studies on RCS have been limited to simple cytotoxicity validation, leaving their target proteins and resulting physiological changes unknown. In this study, we focused on methyl vinyl ketone (MVK), which is one of the main RCS found in cigarette smoke and exhaust gas. We found that MVK suppressed PI3K-Akt signaling, which regulates processes involved in cellular homeostasis, including cell proliferation, autophagy, and glucose metabolism. Interestingly, MVK inhibits the interaction between the epidermal growth factor receptor and PI3K. Cys656 in the SH2 domain of the PI3K p85 subunit, which is the covalently binding site of MVK, is important for this interaction. Suppression of PI3K-Akt signaling by MVK reversed epidermal growth factor-induced negative regulation of autophagy and attenuated glucose uptake. Furthermore, we analyzed the effects of the 23 RCS compounds with structures similar to MVK and showed that their analogs also suppressed PI3K-Akt signaling in a manner that correlated with their similarities to MVK. Our study demonstrates the mechanism of MVK and its analogs in suppressing PI3K-Akt signaling and modulating physiological functions, providing a model for future studies analyzing environmental reactive species.

Human cytomegalovirus attenuates AKT activity by destabilizing insulin receptor substrate proteins.

IMPORTANCE: Human cytomegalovirus (HCMV) requires inactivation of AKT to efficiently replicate, yet how AKT is shut off during HCMV infection has remained unclear. We show that UL38, an HCMV protein that activates mTORC1, is necessary and sufficient to destabilize insulin receptor substrate 1 (IRS1), a model insulin receptor substrate (IRS) protein. Degradation of IRS proteins in settings of excessive mTORC1 activity is an important mechanism for insulin resistance. When IRS proteins are destabilized, PI3K cannot be recruited to growth factor receptor complexes, and hence, AKT membrane recruitment, a rate limiting step in its activation, fails to occur. Despite its penchant for remodeling host cell signaling pathways, our results reveal that HCMV relies upon a cell-intrinsic negative regulatory feedback loop to inactivate AKT. Given that pharmacological inhibition of PI3K/AKT potently induces HCMV reactivation from latency, our findings also imply that the expression of UL38 activity must be tightly regulated within latently infected cells to avoid spontaneous reactivation.

Quinoxalinone substituted pyrrolizine (4h)-induced dual inhibition of AKT and ERK instigates apoptosis in breast and colorectal cancer by modulating mitochondrial membrane potential.

AKT and ERK 1/2 play a pivotal role in cancer cell survival, proliferation, migration, and angiogenesis. Therefore, AKT and ERK 1/2 are considered crucial targets for cancer intervention. In this study, we envisaged the role of AKT and ERK signaling in apoptosis regulation in presence of compound 4h, a novel synthetic derivative of quinoxalinone substituted spiropyrrolizines exhibiting substantial antiproliferative activity in various cancer cell lines. Structurally 4h is a spiropyrrolizine derivative. Molecular docking analysis revealed that compound 4h shows strong binding affinity with AKT-1 (-9.5 kcal/mol) and ERK2 (-9.0 kcal/mol) via binding at allosteric sites of AKT and active site of ERK2. The implications of 4h binding with these two survival kinases resulted in the obstruction for ATP binding, hence, hampering their phosphorylation dependent activation. We demonstrate that 4h mediated apoptotic induction via disruption in the mitochondrial membrane potential of MCF-7 and HCT-116 cells and 4h-mediated inhibition of survival pathways occurred in a wild type PTEN background and is diminished in PTEN-/- cells. In 4T1 mammary carcinoma model, 4h exhibited pronounced reduction in the tumor size and tumor volume at significantly low doses. Besides, 4h reached the highest plasma concentration of 5.8 µM within a period of 1 h in mice model intraperitoneally. Furthermore, 4h showed acceptable clearance with an adequate elimination half-life and satisfactory pharmacokinetic behaviour, thus proclaiming as a potential lead molecule against breast and colorectal cancer by specifically inhibiting simultaneously AKT and ERK1/2 kinases.

Ponatinib Represses Latent HIV-1 by Inhibiting AKT-mTOR.

Although antiretroviral therapy (ART) is effective in suppressing viral replication, it does not cure HIV-1 infection due to the presence of the viral latent reservoir. Rather than reactivating the latent viruses, the "block and lock" strategy aims to shift the viral reservoir to a deeper state of transcriptional silencing, thus preventing viral rebound after ART interruption. Although some latency-promoting agents (LPAs) have been reported, none of them have been approved for clinical application due to cytotoxicity and limited efficacy; therefore, it is important to search for novel and effective LPAs. Here, we report an FDA-approved drug, ponatinib, that can broadly repress latent HIV-1 reactivation in different cell models of HIV-1 latency and in primary CD4+ T cells from ART-suppressed individuals ex vivo. Ponatinib does not change the expression of activation or exhaustion markers on primary CD4+ T cells and does not induce severe cytotoxicity and cell dysfunction. Mechanistically, ponatinib suppresses proviral HIV-1 transcription by inhibiting the activation of the AKT-mTOR pathway, which subsequently blocks the interaction between key transcriptional factors and the HIV-1 long terminal repeat (LTR). In summary, we discovered a novel latency-promoting agent, ponatinib, which could have promising significance for future applications of HIV-1 functional cure.

Investigation of the inhibitory behavior of XFE and mitoxantrone molecules in interaction with AKT1 protein: a molecular dynamics simulation study.

The PI3K/Akt/mTOR pathway is one of the important pathways in many cancers. Akt is a serine-threonine kinase protein identified as a drug target for cancer treatment. Therefore, anticancer drugs are essential therapeutic targets for this pathway. In the current study, the inhibitory effect of two anticancer molecules, XFE and mitoxantrone, on AKT1 protein that can impact the activity of the AKT1 protein was investigated by using molecular docking and molecular dynamics (MD) simulations. The molecular docking results presented a relatively higher binding affinity of the mitoxantrone molecule in interaction with AKT1 than the XFE molecule. These results were validated by the MM/PBSA technique that was performed on obtained trajectories of 25 ns MD simulations. The mitoxantrone molecule has an intense binding energy of - 880.536 kcal/mol with AKT1 protein, while the XFE molecule shows a binding energy value of - 83.569 kcal/mol. Our findings from molecular dynamics simulations indicated that both molecules have favorite interactions with AKT1 protein. Other analyses, such as RMSF and hydrogen binding on trajectories obtained from MD simulations, indicated that the mitoxantrone molecule could be a relatively potent inhibitor for AKT1. Based on the results of this study and the structure of mitoxantrone, it is expected to be a good candidate for cancer treatment as a (PI3K)/Akt/mTOR inhibitor.

The Synergistic Anti-colon Cancer Effect of Aurora A Inhibitors and AKT Inhibitors Through PI3K/AKT Pathway.

BACKGROUND: Both AKT and Aurora inhibitors are a potential therapeutic agent for the treatment of malignant tumors. However, the role of combined inhibition of AKT and Aurora in colon cancer and its underlying mechanism have yet to be fully investigated. OBJECTIVE: To investigate the role of combined AKT and Aurora inhibitors in colon cancer and its underlying mechanisms. METHODS: CCK8 assay, colony formation assay, and flow cytometry were performed to analyze the proliferation and apoptosis of colon cancer cell line SW480 treated with combined AKT inhibitor MK2206 and Aurora inhibitor Alisertib, respectively. And tumor formation and growth were measured in tumor allograft model mice administered with the combined inhibitors. Western blot analysis was used to examine the expression levels of apoptosis-related proteins and signal transduction pathway components. The PI3K agonist 740Y-P and Overexpression of AKT are used to verify whether the PI3K/AKT pathway plays an anti-tumor effect when combined with inhibitory administration. RESULTS: Aurora A inhibitor Alisertib and AKT inhibitor MK2206 displayed consistent and synergistic antiproliferation and proapoptotic effects. Combined inhibition of Aurora A and AKT down-regulated the expression of Bcl-2/Bax and up-regulated the expression of cleaved-caspase-3 and cleaved-PARP. While single-drug treatment can significantly inhibit the expression of P-PI3K and P-AKT as well as increase the expression of P53 and H2A.X, the combined drugs had a more significant inhibitory effect than the single drug. Moreover, administration of PI3K agonist 740Y-P and AKT1 overexpression in experiments proved that the combined drugs exert an anticancer effect by inhibiting the PI3K/AKT pathway. Meanwhile, we showed that the combined administration had an anti-colon cancer effect on tumor allograft mice, and the underlying mechanism involved inhibition of the PI3K/AKT pathway. CONCLUSION: Combined administration of Aurora A inhibitor Alisertib and AKT inhibitor MK2206 can inhibit the proliferation of colon cancer cells and induce apoptosis, while inhibiting tumor growth in vivo. The underlying mechanism may involve the PI3K/AKT pathway and DNA damage pathway.

A Dimerosesquiterpene and Sesquiterpene Lactones from Artemisia argyi Inhibiting Oncogenic PI3K/AKT Signaling in Melanoma Cells.

A library of more than 2500 plant extracts was screened for activity on oncogenic signaling in melanoma cells. The ethyl acetate extract from the aerial parts of Artemisia argyi displayed pronounced inhibition of the PI3K/AKT pathway. Active compounds were tracked with the aid of HPLC-based activity profiling, and altogether 21 active compounds were isolated, including one novel dimerosequiterpenoid (1), one new disesquiterpenoid (2), three new guaianolides (3-5), 12 known sesquiterpenoids (6-17), and four known flavonoids (19-22). A new eudesmanolide derivative (13b) was isolated as an artifact formed by methanolysis. Compound 1 is the first adduct comprising a sesquiterpene lactone and a methyl jasmonate moiety. The absolute configurations of compounds 1 and 3-18 were established by comparison of their experimental and calculated ECD spectra. The absolute configuration for 2 was determined by X-ray diffraction analysis. Guaianolide 8 was the most potent sesquiterpene lactone, inhibiting the PI3K/AKT pathway with an IC50 value of 8.9 ± 0.9 µM.

Discovery of Clinical Candidate NTQ1062 as a Potent and Bioavailable Akt Inhibitor for the Treatment of Human Tumors.

Akt has emerged as an exciting target in oncology due to its critical roles in proliferation, survival, metabolism, metastasis, and invasion in tumor cells. Herein, we describe the discovery and optimization of a series of ATP-competitive Akt inhibitors that possess new chemical scaffolds and exhibit potent enzymatic activities and improved in vivo pharmacokinetic profiles. Remarkably, NTQ1062 (compound 22b) exhibited potent antitumor efficacies in vitro and in vivo, which was accomplished through the optimization of the hinge binder region and the linkage. Subsequent studies of NTQ1062 demonstrated that it possesses good oral pharmacokinetic characteristics and dose-dependent pharmacodynamic effects on downstream biomarkers. In addition, NTQ1062 exhibits a robust antitumor efficacy in xenograft models in which the PI3K-Akt-mTOR pathway was activated. Based on its ideal druglike properties, NTQ1062 is currently being evaluated in a phase I clinical trial for the treatment of advanced solid tumors (CTR20211999).

Inhibition of AKT induces p53/SIRT6/PARP1-dependent parthanatos to suppress tumor growth.

BACKGROUND: Targeting AKT suppresses tumor growth through inducing apoptosis, however, during which whether other forms of cell death occurring is poorly understood. METHODS: The effects of increasing PARP1 dependent cell death (parthanatos) induced by inhibiting AKT on cell proliferation were determined by CCK-8 assay, colony formation assay, Hoechst 33,258 staining and analysis of apoptotic cells by flow cytometry. For the detailed mechanisms during this process, Western blot analysis, qRT-PCR analysis, immunofluorescence and co-immunoprecipitation were performed. Moreover, the inhibition of tumor growth by inducing p53/SIRT6/PARP1-dependent parthanatos was further verified in the xenograft mouse model. RESULTS: For the first time, we identified that inhibiting AKT triggered parthanatos, a new form of regulated cell death, leading to colon cancer growth suppression. For the mechanism investigation, we found that after pharmacological or genetic AKT inhibition, p53 interacted with SIRT6 and PARP1 directly to activate it, and promoted the formation of PAR polymer. Subsequently, PAR polymer transported to outer membrane of mitochondria and resulted in AIF releasing and translocating to nucleus thus promoting cell death. While, blocking PARP1 activity significantly rescued colon cancer from death. Furthermore, p53 deletion or mutation eliminated PAR polymer formation, AIF translocation, and PARP1 dependent cell death, which was promoted by overexpression of SIRT6. Meanwhile, reactive oxygen species production was elevated after inhibition of AKT, which might also play a role in the occurrence of parthanatos. In addition, inhibiting AKT initiated protective autophagy simultaneously, which advanced tumor survival and growth. CONCLUSION: Our findings demonstrated that AKT inhibition induced p53-SIRT6-PARP1 complex formation and the activation of parthanatos, which can be recognized as a novel potential therapeutic strategy for cancer. Video Abstract.

PI3K/AKT/mTOR signalling inhibitor chrysophanol ameliorates neurobehavioural and neurochemical defects in propionic acid-induced experimental model of autism in adult rats.

Autism spectrum disorder (ASD) is a complex neurodevelopmental disorder marked by social and communication deficits as well as repetitive behaviour. Several studies have found that overactivation of the PI3K/AKT/mTOR signalling pathways during brain development plays a significant role in autism pathogenesis. Overexpression of the PI3K/AKT/mTOR signalling pathway causes neurological disorders by increasing cell death, neuroinflammation, and oxidative stress. Chrysophanol, also known as chrysophanic acid, is a naturally occurring chemical obtained from the plant Rheum palmatum. This study aimed to examine the neuroprotective effect of CPH on neurobehavioral, molecular, neurochemical, and gross pathological alterations in ICV-PPA induced experimental model of autism in adult rats. The effects of ICV-PPA on PI3K/AKT/mTOR downregulation in the brain were studied in autism-like rats. Furthermore, we investigated how CPH affected myelin basic protein (MBP) levels in rat brain homogenate and apoptotic biomarkers such as caspase-3, Bax, and Bcl-2 levels in rat brain homogenate and blood plasma samples. Rats were tested for behavioural abnormalities such as neuromuscular dysfunction using an actophotometer, motor coordination using a beam crossing task (BCT), depressive behaviour using a forced swim test (FST), cognitive deficiency, and memory consolidation using a Morris water maze (MWM) task. In PPA-treated rats, prolonged oral CPH administration from day 12 to day 44 of the experimental schedule reduces autistic-like symptoms. Furthermore, in rat brain homogenates, blood plasma, and CSF samples, cellular, molecular, and cell death markers, neuroinflammatory cytokines, neurotransmitter levels, and oxidative stress indicators were investigated. The recent findings imply that CPH also restores abnormal neurochemical levels and may prevent autism-like gross pathological alterations, such as demyelination volume, in the rat brain.

Combining plasma extracellular vesicle Let-7b-5p, miR-184 and circulating miR-22-3p levels for NSCLC diagnosis and drug resistance prediction.

Low-dose computed tomography (LDCT) Non-Small Cell Lung (NSCLC) screening is associated with high false-positive rates, leading to unnecessary expensive and invasive follow ups. There is a need for minimally invasive approaches to improve the accuracy of NSCLC diagnosis. In addition, NSCLC patients harboring sensitizing mutations in epidermal growth factor receptor EGFR (T790M, L578R) are treated with Osimertinib, a potent tyrosine kinase inhibitor (TKI). However, nearly all patients develop TKI resistance. The underlying mechanisms are not fully understood. Plasma extracellular vesicle (EV) and circulating microRNA (miRNA) have been proposed as biomarkers for cancer screening and to inform treatment decisions. However, the identification of highly sensitive and broadly predictive core miRNA signatures remains a challenge. Also, how these systemic and diverse miRNAs impact cancer drug response is not well understood. Using an integrative approach, we examined plasma EV and circulating miRNA isolated from NSCLC patients versus screening controls with a similar risk profile. We found that combining EV (Hsa-miR-184, Let-7b-5p) and circulating (Hsa-miR-22-3p) miRNAs abundance robustly discriminates between NSCLC patients and high-risk cancer-free controls. Further, we found that Hsa-miR-22-3p, Hsa-miR-184, and Let-7b-5p functionally converge on WNT/ßcatenin and mTOR/AKT signaling axes, known cancer therapy resistance signals. Targeting Hsa-miR-22-3p and Hsa-miR-184 desensitized EGFR-mutated (T790M, L578R) NSCLC cells to Osimertinib. These findings suggest that the expression levels of circulating hsa-miR-22-3p combined with EV hsa-miR-184 and Let-7b-5p levels potentially define a core biomarker signature for improving the accuracy of NSCLC diagnosis. Importantly, these biomarkers have the potential to enable prospective identification of patients who are at risk of responding poorly to Osimertinib alone but likely to benefit from Osimertinib/AKT blockade combination treatments.

Propranolol inhibits cell viability and expression of the pro-tumorigenic proteins Akt, NF-ĸB, and VEGF in oral squamous cell carcinoma.

BACKGROUND: Propranolol (PPL) has been suggested as an option for the treatment of various types of cancer. However, data regarding its effectiveness against oral cancer are scarce. Thus, we aimed to evaluate the antitumor potential of PPL in oral squamous cell carcinoma (OSCC) in vitro. METHODS: OSCC cell lines, SCC-9, SCC-25, and Cal27, were treated with PPL at different times and concentrations. OSCC cells were treated with PPL alone or in combination with cisplatin (CDDP) or 5-fluorouracil (5-FU). Cell viability was determined using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The expression of phosphorylated (p)-Akt, p-S6, p-PTEN, p-P65, and VEGF was verified by immunofluorescence. The migratory activity of OSCC cells was evaluated using a wound-healing assay. RESULTS: PPL reduced OSCC cell viability in a dose- and time-dependent manner. Concentrations above 300 µM, 110 µM, and 100 µM for SCC-9, Cal27, and SCC-25, respectively, significantly eliminated tumor cells. The combination of PPL with CDDP and 5-FU enhanced their antitumor effects. There was a modest difference between the use of the IC30 and IC50 of PPL in the combinatory options. PPL downregulated p-P65 NF-ĸB and VEGF expression in SCC-9 and Cal27 cells but not in SCC-25 cells. PPL inhibited the phosphorylation of Akt and s6 and increased the phosphorylation of PTEN in all OSCC cell lines studied. PPL inhibited OSCC cell migration after 24 h of treatment. CONCLUSION: PPL was effective against oral cancer cells and enhanced standard-of-care. PPL inhibited cell viability and the expression of pAkt, NF-ĸB, and VEGF.

Inhibition of the Akt/PKB Kinase Increases Nav1.6-Mediated Currents and Neuronal Excitability in CA1 Hippocampal Pyramidal Neurons.

In neurons, changes in Akt activity have been detected in response to the stimulation of transmembrane receptors. However, the mechanisms that lead to changes in neuronal function upon Akt inhibition are still poorly understood. In the present study, we interrogate how Akt inhibition could affect the activity of the neuronal Nav channels with while impacting intrinsic excitability. To that end, we employed voltage-clamp electrophysiological recordings in heterologous cells expressing the Nav1.6 channel isoform and in hippocampal CA1 pyramidal neurons in the presence of triciribine, an inhibitor of Akt. We showed that in both systems, Akt inhibition resulted in a potentiation of peak transient Na+ current (INa) density. Akt inhibition correspondingly led to an increase in the action potential firing of the CA1 pyramidal neurons that was accompanied by a decrease in the action potential current threshold. Complementary confocal analysis in the CA1 pyramidal neurons showed that the inhibition of Akt is associated with the lengthening of Nav1.6 fluorescent intensity along the axonal initial segment (AIS), providing a mechanism for augmented neuronal excitability. Taken together, these findings provide evidence that Akt-mediated signal transduction might affect neuronal excitability in a Nav1.6-dependent manner.

10-DEBC Hydrochloride as a Promising New Agent against Infection of Mycobacterium abscessus.

Mycobacterium abscessus (M. abscessus) causes chronic pulmonary infections. Its resistance to current antimicrobial drugs makes it the most difficult non-tuberculous mycobacteria (NTM) to treat with a treatment success rate of 45.6%. Therefore, there is a need for new therapeutic agents against M. abscessus. We identified 10-DEBC hydrochloride (10-DEBC), a selective AKT inhibitor that exhibits inhibitory activity against M. abscessus. To evaluate the potential of 10-DEBC as a treatment for lung disease caused by M. abscessus, we measured its effectiveness in vitro. We established the intracellular activity of 10-DEBC against M. abscessus in human macrophages and human embryonic cell-derived macrophages (iMACs). 10-DEBC significantly inhibited the growth of wild-type M. abscessus and clinical isolates and clarithromycin (CLR)-resistant M. abscessus strains. 10-DEBC's drug efficacy did not have cytotoxicity in the infected macrophages. In addition, 10-DEBC operates under anaerobic conditions without replication as well as in the presence of biofilms. The alternative caseum binding assay is a unique tool for evaluating drug efficacy against slow and nonreplicating bacilli in their native caseum media. In the surrogate caseum, the mean undiluted fraction unbound (fu) for 10-DEBC is 5.696. The results of an in vitro study on the activity of M. abscessus suggest that 10-DEBC is a potential new drug for treating M. abscessus infections.

Loss of TIPE3 reduced the proliferation, survival and migration of lung cancer cells through inactivation of Akt/mTOR, NF-κB, and STAT-3 signaling cascades.

Lung cancer is the foremost cause of cancer related mortality among men and one of the most fatal cancers among women. Notably, the 5-year survival rate of lung cancer is very low; 5% in developing countries. This low survival rate can be attributed to factors like late stage diagnosis, rapid postoperative recurrences in the patients undergoing treatment and development of chemoresistance against different agents used for treating lung cancer. Therefore, in this study we evaluated the potential of a recently identified protein namely TIPE3 which is known as a transfer protein of lipid second messengers as a lung cancer biomarker. TIPE3 was found to be significantly upregulated in lung cancer tissues indicating its role in the positive regulation of lung cancer. Supporting this finding, knockout of TIPE3 was also found to reduce the proliferation, survival and migration of lung cancer cells and arrested the G2 phase of cell cycle through inactivation of Akt/mTOR, NF-κB, STAT-3 signaling. It is well evinced that tobacco is the major risk factor of lung cancer which affects both males and females. Therefore, this study also evaluated the involvement of TIPE3 in tobacco mediated lung carcinogenesis. Notably, this study shows for the first time that TIPE3 positively regulates tobacco induced proliferation, survival and migration of lung cancer through modulation of Akt/mTOR signaling. Thus, TIPE3 plays critical role in the pathogenesis of lung cancer and hence it can be specifically targeted to develop novel therapeutic strategies.