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Although single treatment with sodium‐glucose cotransporter‐2 inhibitors (SGLT2i) or vitamin D3 (VD3) inhibited metabolic dysfunction‐associated steatohepatitis (MASH) development in diabetic patients, their combination has not been explored previously. Hence, this study investigated the hepatoprotective effects of SGLT2i (empagliflozin) and/or VD3 against MASH in type 2 diabetic mice. Forty Mice were assigned into negative (NC) and positive (PC) controls, SGLT2i, VD3, and SGLT2i + VD3 groups. All animals, except the NC group, received high‐fructose/high‐fat diet (8 weeks) followed by diabetes induction. Diabetic mice then received another cycle of high‐fructose/high‐fat diet (4 weeks) followed by 8 weeks of treatment (five times/week) with SGLT2i (5.1 mg/kg/day) and/or VD3 (410 IU/Kg/day). The PC group demonstrated hyperglycaemia, dyslipidaemia, elevated liver enzymes, and increased non‐alcoholic fatty liver disease activity score (NAS) with fibrosis. Hepatic glucose transporting molecule (SGLT2) with lipogenesis (SREBP‐1/PPARγ), oxidative stress (MDA/H2O2), inflammation (IL1β/IL6/TNF‐α), fibrosis (TGF‐β1/α‐SMA), and apoptosis (TUNEL/Caspase‐3) markers alongside the PI3K/AKT/mTOR pathway increased in the PC group. Conversely, hepatic insulin‐dependent glucose transporter (GLUT4), lipolytic (PPARα/INSIG1), antioxidant (GSH/GPx1/SOD1/CAT), and anti‐inflammatory (IL‐10) molecules with the inhibitor of PI3K/AKT/mTOR pathway (PTEN) decreased in the PC group. Whilst SGLT2i monotherapy outperformed VD3, their combination showed the best attenuation of hyperglycaemia, dyslipidaemia, and fibrosis with the strongest modulation of hepatic glucose‐transporting and lipid‐regulatory molecules, PI3K/AKT/mTOR pathway, and markers of oxidative stress, inflammation, fibrosis, and apoptosis. This study is the first to reveal boosted hepatoprotection for SGLT2i and VD3 co‐therapy against diabetes‐induced MASH, possibly via enhanced metabolic control and modulation of hepatic PI3K/AKT/mTOR, anti‐inflammatory, anti‐oxidative, and anti‐fibrotic pathways. [ABSTRACT FROM AUTHOR]

1,3,4‐Thiadiazine‐based components have gained the attention as they afford significant intervention for cancer therapy. We aimed at assessing the in vivo antitumor activity of sodium 2‐[(4‐oxidobenzylidene) amino]‐6H‐1,3,4‐thiadiazine‐5‐c (SOTA) versus Ehrlich ascites carcinoma (EAC) cells in female mice's peritoneal cavity. An advantageous interaction of the test compound with the receptors p53 (2J1X), Caspase‐3 (3KJF), mTOR (3QAR), and PI3K (4JPS) was revealed by the docking study. The in vivo study of the test compound against EAC, equated with the EAC control mice, EAC bearing mice that received the test compound by i.p. injection proven a substantial decrease in the viability of tumor cell by 70%. Treatment with the tested compound increased total antioxidants capacity and decreasing malondialdehyde levels. Also, the apoptotic activity of the test compound was confirmed by up regulation of caspase‐3 and p53 and downregulation of PI3K and mTOR. Through the liver, kidney, and heart function assessments, the examined component has no adverse effects on either of the two organs, which were supported by a histological study. Significant positive and negative associations among variables were discovered, according to our research. Through the induction of apoptosis and antioxidant effects, the test compound show potential anticancer activity against EAC cells. The treatment with SOTA eliminated most of the pathological abnormalities brought on by EAC cells in mice, according to the results of tests on the liver, kidney, and heart as well as the histological investigation. Taking together, the tested compound SOTA is promising chemotherapeutic agent as supported by targeting PI3k/mTOR pathway. [ABSTRACT FROM AUTHOR]

PI3K/Akt/mTOR pathway activation causes relapse and resistance after radiotherapy in breast cancer (BC). We aimed to radiosensitize BC cell lines to irradiation (IR) by PKI-402, a dual PI3K/mTOR inhibitor. We performed cytotoxicity, clonogenicity, hanging drop, apoptosis and double-strand break detection, and phosphorylation of 16 essential proteins involved in the PI3K/mTOR pathway. Our findings showed that PKI-402 has cytotoxic efficiency in all cell lines. Clonogenic assay results showed that PKI-402 plus IR inhibited the colony formation ability of MCF-7 and breast cancer stem cell lines. Results showed that PKI-402 plus IR causes more apoptotic cell death than IR alone in the MCF-7 cells but did not cause significant changes in the MDA-MB-231. γ-H2AX levels were increased in MDA-MB-231 in PKI-402 plus IR groups, whereas we did not observe any apoptotic and γ-H2AX induction in BCSCs and MCF-10A cells in all treatment groups. Some pivotal phosphorylated proteins of the PI3K/AKT pathway decreased, several proteins increased and others did not change. In conclusion, if the combined use of PKI-402 with radiation is supported by in vivo studies, it can contribute to the treatment options and the course of the disease. [ABSTRACT FROM AUTHOR]

Breast cancer is a common form of cancer that affects both men and women. One of the most common types of genomic flaws in cancer is the aberrations in the PI3K/AKT/mTOR pathway. The benefit of dual targeting PI3K as well as mTOR is that the kinase-positive feedback loops are more effectively inhibited. Therefore, in the current study, structure-based models like molecular docking, MM-GBSA, Qikprop, induced fit docking, simulated molecular dynamics (MD), and thermal MM-GBSA were used to identify the phytochemicals from the zinc 15 database, which may inhibit PI3K and mTOR. After docking the phytochemicals with PI3K (PDB 4FA6), ten ligands based on the docking score were selected, among which salvianolic acid C had the highest docking score. Hence, salvianolic acid A was also docked. All the ligands taken showed a binding energy of greater than − 30 kcal/mol. The predicted ADME showed that the ligands have druggable properties. By performing MD of the top five ligands and salvianolic acid A, it was found that ZINC000059728582, ZINC000257545754, ZINC000253532301, and salvianolic acid A form a stable complex with PI3K protein, among which ZINC000014690026 showed interaction with Val 882 for more than 89% of the time. Salvianolic acid A is already proven to suppress tumor growth in acute myeloid leukemia by inhibiting PI3K/AKT pathway, but the exact protein target is unknown. Therefore, the present study identifies new molecules and provides evidence for salvianolic acid A for dual inhibition. Further experiments must be performed both in vitro and in vivo to support the predictions of these computational tools. [ABSTRACT FROM AUTHOR]

Circular RNAs (CircRNAs) are key regulators in the development and progression of human cancers. However, the biological roles and mechanisms of circRNAs in gastric cancer (GC) remain largely unknown. Analyzing circRNA microarray dataset (GSE102686) and clinical specimens, a novel circRNA termed hsa_circ_0001627, was identified and it was highly expressed in CC cancerous tissues and cells, and was associated with poor clinical outcomes. Functionally, hsa_circ_0001627 silencing impaired the malignant progression of CC cells and the growth of CC xenografts in nude mice. Mechanistically, hsa_circ_0001627 acted as a miR-1225-5p sponge, thus indirectly regulating FNDC3B and leading to the activation of PI3K/mTOR signaling pathway. Collectively, the present study indicates that hsa_circ_0001627 regulates miR-1225-5p/FNDC3B/PI3K/mTOR axis and functions as an oncogene in CC progression, suggesting the potential therapeutic use of hsa_circ_0001627 in CC treatment. [ABSTRACT FROM AUTHOR]

Objective: Multiple myeloma is a hematologic malignancy in which targeting phosphoinositide 3 kinase (PI3K) and/or the mammalian target of rapamycin (mTOR) individually has been shown to have anti-proliferative effects, however, inhibiting both proteins simultane9 has been reported to have more effective results for its treatment. The aim of this study is to determine the molecular interactions and predicted inhibitory effects of 40 different dual inhibitors on mTOR, PI3Kδ, and PI3Kγ to propose potentially the most effective dual inhibitor that targets the PI3Kδ and PI3Kγ isoforms as well as the mTOR proteins since those isoforms are known to be predominant in multiple myeloma patients. Therefore, the focus in this study is built around the specific targeting of the PI3Kδ and PI3Kγ isoforms from the multiple myeloma perspective. Materials and Methods: In silico docking experiments were conducted to determine the binding energies for different ligands that target mTOR, PI3Kδ, and PI3Kγ. Protein-dual inhibitor complexes and the amino acids and bond types were visualized to identify molecular interactions. The absorption, distribution, metabolism, and excretion properties of dual inhibitors were analyzed and evaluated. Results: The binding affinity values were found to be between -7 and -9.9 kcal/mol. The toxicity prediction values of the selected dual inhibitors were obtained from the Pro-Tox-II web tool and classified according to the globally harmonized system of classification of labeling of chemicals. Conclusion: Correspondingly, among all dual inhibitors, Vistusertib is determined to be a promising compound against multiple myeloma cells by inhibiting both PI3Kδ and PI3Kγ as well as mTORC1/2. [ABSTRACT FROM AUTHOR]

Background: Outer membrane protein A (OmpA) is the major virulence factor of Acinetobacter baumannii and plays a wide role in the pathogenesis and antimicrobial resistance of A. baumannii. Dendritic cells (DCs) are the most effective antigen‐presenting cells and play a crucial role in regulating the immune response to multiple antigens and immune sentries. We aimed to study the role and molecular mechanisms of OmpA‐induced mouse bone marrow‐derived dendritic cells (BMDCs) autophagy in the immune response of A. baumannii. Methods: First, purified A. baumannii OmpA was assessed by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE) and western blot. OmpA effect on BMDCs viability was evaluated by MTT assay. BMDCs were pretreated with autophagy inhibitor chloroquine or transfected with overexpression plasmids (oe‐NC or oe‐PI3K). Then BMDCs apoptosis, inflammatory cytokines, protein kinase B (PI3K)/mammalian target of rapamycin (mTOR) pathway, and autophagy‐related factors levels were evaluated. Results: SDS‐PAGE and western blot verified the successful purification of OmpA. BMDCs viability repressed gradually with the increase of OmpA concentration. OmpA treatment of BMDCs led to apoptosis and inflammation in BMDCs. OmpA caused incomplete autophagy in BMDCs, and light chain 3 (LC3), Beclin1, P62, and LC3II/I levels were significantly elevated with the increase of the time and concentration of OmpA treatment. Chloroquine reversed OmpA effects on autophagy in BMDCs, that was, LC3, Beclin1, and LC3II/I levels were reduced, while P62 level was elevated. Furthermore, chloroquine reversed OmpA effects on apoptosis and inflammation in BMDCs. PI3K/mTOR pathway‐related factor expression was affected by OmpA treatment of BMDCs. After overexpression of PI3K, these effects were reversed. Conclusions: A. baumannii OmpA induced autophagy in BMDCs involving the PI3K/mTOR pathway. Our study may provide a novel therapeutic target and theoretical basis for treating infections caused by A. baumannii. [ABSTRACT FROM AUTHOR]

Abstract Background Lung cancer is one of the most lethal cancers worldwide. Cisplatin, a widely used anti‐lung cancer drug, has been limited in clinical application due to its drug resistance. Medicines targeting mitochondrial electron transport chain (ETC) complexes may be effective candidates for cisplatin‐based chemotherapy. Methods In this study, the small molecule drug library from Food and Drug Administration FDA was used to screen for medicines targeting ETC. MTT and colony formation assays were used to investigate cell proliferation. Flow cytometry was employed to analyze cell cycle, apoptosis, reactive oxygen species (ROS), and mitochondrial membrane potential. Wound scratch and transwell assays were used to detect migration and invasion abilities. The activities of the ETC complex were tested using kits. Western blot analysis was used to investigate the expressions of related proteins. A mouse xenograft model was constructed to verify the antitumor effect in vivo. Results The results showed that mubritinib can reduce the activation of the PI3K/mTOR signal pathway, disrupt mitochondrial function, significantly increase ROS levels and induce oxidative stress, and ultimately exert its antitumor effect against non‐small cell lung cancer (NSCLC) both in vivo and in vitro. In addition, the combination of cisplatin and mubritinib can improve the tumor‐suppressive effect of cisplatin. Conclusion Mubritinib can upregulate intracellular ROS concentration and cell apoptosis, inhibit the PI3K signaling pathway and interfere with the function of mitochondria, thus reducing cell proliferation and increasing ROS induced apoptosis by reducing the activation of Nrf2 by PI3K.

Background: Lung cancer is one of the most lethal cancers worldwide. Cisplatin, a widely used anti‐lung cancer drug, has been limited in clinical application due to its drug resistance. Medicines targeting mitochondrial electron transport chain (ETC) complexes may be effective candidates for cisplatin‐based chemotherapy. Methods: In this study, the small molecule drug library from Food and Drug Administration FDA was used to screen for medicines targeting ETC. MTT and colony formation assays were used to investigate cell proliferation. Flow cytometry was employed to analyze cell cycle, apoptosis, reactive oxygen species (ROS), and mitochondrial membrane potential. Wound scratch and transwell assays were used to detect migration and invasion abilities. The activities of the ETC complex were tested using kits. Western blot analysis was used to investigate the expressions of related proteins. A mouse xenograft model was constructed to verify the antitumor effect in vivo. Results: The results showed that mubritinib can reduce the activation of the PI3K/mTOR signal pathway, disrupt mitochondrial function, significantly increase ROS levels and induce oxidative stress, and ultimately exert its antitumor effect against non‐small cell lung cancer (NSCLC) both in vivo and in vitro. In addition, the combination of cisplatin and mubritinib can improve the tumor‐suppressive effect of cisplatin. Conclusion: Mubritinib can upregulate intracellular ROS concentration and cell apoptosis, inhibit the PI3K signaling pathway and interfere with the function of mitochondria, thus reducing cell proliferation and increasing ROS induced apoptosis by reducing the activation of Nrf2 by PI3K. [ABSTRACT FROM AUTHOR]

Simple Summary: We determined the sensitivity of several conjunctival melanoma cell lines to kinase inhibitors as well as a few other inhibitors using an image-based high throughput drug screening assay with 542 compounds. All cell lines demonstrated sensitivity to cell cycle inhibition, especially with polo-like inhibitors. The response to MAPK pathway inhibition was better in the presence of BRAFV600E mutations, while the response to PI3k/mTOR inhibition was better in the presence of the NRASQ61L mutation. Our study uncovers a large panel of new vulnerabilities in conjunctival melanoma and establishes the background for the expansion of therapeutic options in the management of this tumor. Recent evidence suggests that numerous similarities exist between the genomic landscapes of both conjunctival and cutaneous melanoma. Since alterations of several components of the MAP kinases, PI3K/mTOR, and cell cycle pathways have been reported in conjunctival melanoma, we decided to assess the sensitivity of conjunctival melanoma to targeted inhibition mostly of kinase inhibitors. A high content drug screening assay based on automated fluorescence microscopy was performed in three conjunctival melanoma cell lines with different genomic backgrounds with 489 kinase inhibitors and 53 other inhibitors. IC50 and apoptosis induction were respectively assessed for 53 and 48 compounds. The genomic background influenced the response to MAK and PI3K/mTOR inhibition, more specifically cell lines with BRAF V600E mutations were more sensitive to BRAF/MEK inhibition, while CRMM2 bearing the NRASQ61L mutation was more sensitive to PI3k/mTOR inhibition. All cell lines demonstrated sensitivity to cell cycle inhibition, being more pronounced in CRMM2, especially with polo-like inhibitors. Our data also revealed new vulnerabilities to Hsp90 and Src inhibition. This study demonstrates that the genomic background partially influences the response to targeted therapy and uncovers a large panel of potential vulnerabilities in conjunctival melanoma that may expand available options for the management of this tumor. [ABSTRACT FROM AUTHOR]

Mulberry leaves have antioxidant activity and anti‑inflammatory effects in several types of cells. However, the efficacy of mulberry leaves fermented with Cordyceps militaris remains unknown. Therefore, the present study aimed to investigate whether the ethanol extracts of mulberry leaves fermented with C. militaris (EMfC) can prevent lipopolysaccharide (LPS)‑induced inflammation and autophagy in macrophages. To achieve this, RAW264.7 cells pretreated with three different dose of EMfCs were subsequently stimulated with LPS, and examined for alterations in the regulatory factors of inflammatory responses and key parameters of the autophagy signaling pathway. EMfC treatment inhibited the generation of reactive oxidative species; however, significant activity was observed for 2,2‑diphenyl‑1‑picrylhydrazyl (DPPH) radical scavenging (IC50=579.6703 mg/ml). Most regulatory factors in inflammatory responses were significantly inhibited following treatment with EMfC, without any significant cellular toxicity. EMfC‑treated groups exhibited marked suppression of nitrogen oxide (NO) levels, mRNA expression levels of iNOS/COX‑2, levels of all inflammatory cytokines (TNF‑α, IL‑1β and IL‑6) and phosphorylation of MAPK members, as well as recovery of cell cycle progression. Furthermore, similar effects were observed in the LPS‑induced autophagy signaling pathway of RAW264.7 cells. The expression levels of microtubule‑associated protein 1A/1B‑light chain 3 (LC3) and Beclin exhibited a dose‑dependent decrease in the EMfC+LPS‑treated groups compared with in the Vehicle+LPS‑treated group, whereas the phosphorylation of PI3K and mTOR were enhanced in a dose‑dependent manner in the same groups. Overall, the results of the present study provide evidence that exposure to EMfC protects against LPS‑induced inflammation and autophagy in RAW264.7 cells. These results indicated that EMfC is a potential candidate for treatment of inflammatory diseases. [ABSTRACT FROM AUTHOR]

Transforming growth factor beta (TGF-β) is a multifunctional cytokine with important functions in cell proliferation and differentiation. TGF-β is highly expressed in several types of cancers and promotes tumor invasion and metastasis. However, the role of TGF-β in osteosarcoma progression is poorly understood. In the present study, we found that TGF-β is highly expressed in osteosarcoma cells and tissues, and is associated with high Ennecking stage (P = 0.033), metastasis, and recurrence. TGF-β-knockdown osteosarcoma cell lines were established using siRNA (si-TGF-β). Cells transfected with si-TGF-β exhibited significantly reduced proliferation, migration/invasion, and colony formation abilities, and increased levels of cell apoptosis. In addition, si-TGF-β treatment reduced spheroid size, the ratio of CD133-positive cells, and expression of SOX-2, Nanog, and Oct-3/4 in osteosarcoma cells. Mechanistically, PI3K/mTOR phosphorylation is inhibited by TGF-β knockdown. Pretreatment with 25 µM LY294002, a PI3K-specific inhibitor, further enhanced the si-TGF-β-induced suppression of osteosarcoma progression. Taken together, these results reveal a novel role for TGF-β in osteosarcoma progression and modulation of stemness-related traits and indicate that TGF-β may be of value as a therapeutic target for the treatment of osteosarcoma. [ABSTRACT FROM AUTHOR]

Abstract Background Phosphatase and Tensin homolog (PTEN) is a tumor suppressor gene. Loss of its function is the most frequent genetic alteration in endometrioid endometrial cancers (70–80%) and high grade tumors (90%). We assessed the sensitivity of endometrial cancer cell lines to PARP inhibitors (olaparib and BMN-673) and a PI3K inhibitor (BKM-120), alone or in combination, in the context of their PTEN mutation status. We also highlighted a direct pathway linking PTEN to DNA repair. Methods Using endometrial cancer cellular models with known PTEN status, we evaluated their homologous recombination (HR) functionality by RAD51 foci formation assay. The 50% Inhibitory concentration (IC50) of PI3K and PARP inhibitors in these cells was assessed, and western blotting was performed to determine the expression of proteins involved in the PI3K/mTOR pathway. Moreover, we explored the interaction between RAD51 and PI3K/mTOR by immunofluorescence. Next, the combination effect of PI3K and PARP inhibitors on cell proliferation was evaluated by a clonogenic assay. Results Cells with mutated PTEN showed over-activation of the PI3K/mTOR pathway. These cells were more sensitive to PARP inhibition compared to PTEN wild-type cells. In addition, PI3K inhibitor treatment reduced RAD51 foci formation in PTEN mutated cells, and sensitized these cells to PARP inhibitor. Conclusion Targeting both PARP and PI3K might lead to improved personalized therapeutic approaches in endometrial cancer patients with PTEN mutations. Understanding the complex interaction of PTEN mutations with DNA repair in endometrial cancer will help to better select patients that are likely to respond to some of the new and costly targeted therapies.

OBJECTIVE: Merlin is encoded by Neurofibromatosis type 2 gene (NF-2), a tumor suppressor gene, which causes some multiple tumors forming disease of the nervous system in case of function loss. Bioinformatics analysis suggested that patients with NF-2 mutation had a worse prognosis, while it was associated with PI3K/mTOR activation, implying abnormal apoptosis in NF-2 mutation related tumors. Hence, we supposed that the inhibitors of PI3K/ mTOR pathway might play a role in suppressing the tumor proliferation. MATERIALS AND METHODS: Two representative NF-2 mutation tumor model of NCI-H2452 and HEI193 cell lines were adopted, while two PI3K/mTOR pathway inhibitors Trametinib and Vistusertib were chosen to study the proliferation and apoptosis of the tumor cells. RESULTS: CCK8 cell counting experiment showed that both Trametinib and Vistusertib could inhibit the proliferation of NCI-H2452 cell in vitro, while the combination of Trametinib and Vistusertib was more significant. Flow cytometry results showed that both Trametinib and Vistusertib could enhance apoptosis of NCI-H2452 cell in vitro, while the combination of Trametinib and Vistusertib was more significant. Similar results were also achieved for HEI193 cell lines. In vivo tumorigenicity experiments demonstrated that the tumor volume and weight were significantly decreased by both Trametinib and Vistusertib, while their combination had the most significant effect. Western blot results demonstrated that both Trametinib and Vistusertib could inhibit PI3K/mTOR /MEK pathway and enhance the expression of merlin. CONCLUSIONS: We found that PI3K/mTOR inhibitor could decrease the proliferation of NF-2 mutation tumor cell lines by enhancing apoptosis, while the combination of two drugs might have a better effect. [ABSTRACT FROM AUTHOR]

Abstract: Objective: This study was designed to explore the relationship between ginsenoside Rb1 (Grb1) and high‐load heart failure (HF) in rats. Methods: The parameters of cardiac systolic function (left ventricular posterior wall thickness (LVPWT), left ventricular internal diastolic diameter (LVID), fraction shortening (FS) and mitral valves (MVs)) of rat hearts in each group were inspected by echocardiogram. The expressions of rat myocardial contractile proteins, autophagy‐related proteins and the activation of Rho/ROCK and PI3K/mTOR pathways were detected by Western blot. Key findings: LVPWT, FS, MVs and the expression of myocardial contractile proteins α‐MHC, apoptosis‐related proteins Bcl‐2 and signalling pathway involved proteins pAkt and mTOR were significantly reduced in the HF, HF+5 mg/kg Grb1 (HF+Grb1‐5) and HF+Grb1+arachidonic acid (AA) groups with LVID, β‐MHC, cell apoptosis, cell autophagy and Rho/ROCK significantly increased compared with the control group, of which the tendency was contrary to the HF+20 mg/kg Grb1 (HF+Grb1‐20) group compared with the HF group (P < 0.05). In the HF+Grb1+AA group, there was no significant change in the above indexes compared with the HF group. Conclusions: The results indicated that Grb1 can exert anti‐HF function by inhibiting cardiomyocyte autophagy of rats through regulation of Rho/ROCK and PI3K/mTOR pathways. [ABSTRACT FROM AUTHOR]

Background: Phosphatase and Tensin homolog (PTEN) is a tumor suppressor gene. Loss of its function is the most frequent genetic alteration in endometrioid endometrial cancers (70-80%) and high grade tumors (90%). We assessed the sensitivity of endometrial cancer cell lines to PARP inhibitors (olaparib and BMN-673) and a PI3K inhibitor (BKM-120), alone or in combination, in the context of their PTEN mutation status. We also highlighted a direct pathway linking PTEN to DNA repair.Methods: Using endometrial cancer cellular models with known PTEN status, we evaluated their homologous recombination (HR) functionality by RAD51 foci formation assay. The 50% Inhibitory concentration (IC50) of PI3K and PARP inhibitors in these cells was assessed, and western blotting was performed to determine the expression of proteins involved in the PI3K/mTOR pathway. Moreover, we explored the interaction between RAD51 and PI3K/mTOR by immunofluorescence. Next, the combination effect of PI3K and PARP inhibitors on cell proliferation was evaluated by a clonogenic assay.Results: Cells with mutated PTEN showed over-activation of the PI3K/mTOR pathway. These cells were more sensitive to PARP inhibition compared to PTEN wild-type cells. In addition, PI3K inhibitor treatment reduced RAD51 foci formation in PTEN mutated cells, and sensitized these cells to PARP inhibitor.Conclusion: Targeting both PARP and PI3K might lead to improved personalized therapeutic approaches in endometrial cancer patients with PTEN mutations. Understanding the complex interaction of PTEN mutations with DNA repair in endometrial cancer will help to better select patients that are likely to respond to some of the new and costly targeted therapies. [ABSTRACT FROM AUTHOR]

The failure of therapies targeting tumor angiogenesis may be caused by anti-angiogenic resistance mechanisms induced by VEGF and non-VEGF pathways alterations. Anti-angiogenic therapy failure is also attributed to immune system, acting by tumor-associated macrophages that release pro-angiogenic factors and a consequent increase of blood vessels. Recently, in a study by Rheal et al., a new angiogenic receptor, epidermal growth factor, latrophilin, and 7 trans-membrane domain-containing protein 1 on chromosome 1(ELTD1) has been identified as a promising glioma biomarker. In this study we aim to analyse whether this receptor may be used as a target molecule in glioblastoma therapy. Our results showed that small interfering RNA silencing ELTD1 caused cytotoxicity in glioblastoma cells. We also found that PDGFR, VEGFR, and their common PI3K/mTOR intracellular pathway inactivation-induced cytotoxicity in glioblastoma cells. Further, we found high percent of cytotoxicity in a low passage glioblastoma cell line after BEZ235 (a dual inhibitor of PI3K/mTOR pathway) treatment at nanomolar concentrations, compared to AG1433 (a PDGFR inhibitor) and SU1498 (a VEGFR inhibitor) that were only cytotoxic at micromolar ranges. In the future, these could prove as attractive therapeutic targets in single therapy or coupled with classic therapeutic approaches such as chemotherapy of radiotherapy. [ABSTRACT FROM PUBLISHER]

Objective To study the anti-tumor effect and mechanism of intraperitoneal injection of celastrol on ovarian cancer xenografts in rats. Methods Sixty adult F344 rats were randomly divided into groups A, B and C, with 20 rats in each group. Rats of the three groups were used to make animal models of ovarian cancer xenografts, and all models were successful. After making the models, the rats in the group B were injected with 40 mg/(kg·D-1) cisplatin injection, and group C was injected with 40 mg/(kg · D-1) celastrol, and the same volume of normal saline was injected into the rat models of the group A, for 30 d. Ten rats were killed in each group before administration and 30 d after administration, and the tumor volume was calculated. The PI3K, p-mTOR and PTEN proteins of the transplanted tumor tissues of rats were detected by Western blotting. Results The volume of xenografts in each group at 30 d after administration was higher than that before administration(all P < 0.05); at 30 d after administration, the tumor volume in the group C was smaller than that in the groups A and B(all P < 0.05), and the volume of tumor in the group B was smaller than that in the group A(P< 0.05). At 30 d after administration, the relative expression of PI3K, p-mTOR, and PTEN in the ovarian cancer xenograft tissues of group C was higher than that in the group B(P < 0.05), and group B was higher than group A(P <0.05). Conclusion Intraperitoneal injection of celastrol can inhibit the metastasis of ovarian cancer in rats, its effect is better than cisplatin, and the anti-tumor effect of celastrol may be related to PI3K/mTOR signaling pathway and PTEN. [ABSTRACT FROM AUTHOR]

Cell experiments were implemented in this research to investigate the molecular mechanism by which H19 affected senescence of human DFs (HDFs). By conducting luciferase assay, we analyzed the relations between H19 and miR-296-5p and between miR-296-5pand IGF2. Ectopic expression and silencing experiments were performed to assess their effects on the growth and senescence of HDFs. β-Gal, DUSP6, p21, and p16 were utilized as markers for evaluating cell senescence. H19 and IGF2 were downregulated but miR-296-5p was upregulated in the aging HDFs. Mechanistic analysis showed that H19 bound to miR-296-5p to upregulate the miR-296-5p target, IGF2, and that activating the PI3K/mTOR pathway and upregulating AQP3 expression in HDFs. H19 upregulation or miR-296-5p downregulation facilitated the viability but restrained the senescence of HDFs, accompanied with reductions in the expression of cell senescence markers. Knockdown of IGF2 expression counteracted the effects induced by miR-296-5p inhibition, while inhibited PI3K/mTOR pathway reversed the impacts of IGF2 overexpression on HDFs. In summary, our data provided a novel insight into the anti-senescent mechanism of H19 in HDFs, offers a better understanding of cellular mechanisms during the process of aging. • H19 overexpression stimulates HDF viability and inhibits HDF senescence. • H19 competitively binds to miR-296-5p to upregulate IGF2 in HDFs. • miR-296-5p targets IGF2 to repress HDF viability and accelerate HDF senescence. • IGF2 activates PI3K/mTOR/AQP3 to limit viability and enhance senescence of HDFs. • This study provides a new molecular target for delaying skin aging. [ABSTRACT FROM AUTHOR]

The phosphoinositide-3-kinase (PI3K) pathway has widely been considered as a potential therapeutic target for head and neck cancer (HNC); however, the application of PI3K inhibitors is often overshadowed by the induction of drug resistance with unknown mechanisms. In this study, PII3K inhibitor resistant cancer cells were developed by prolonged culturing of cell lines with BEZ235, a dual PI3K and mammalian target of rapamycin (mTOR) inhibitor. The drug resistant HNC cells showed higher IC50 of the proliferation to inhibitors specifically targeting PI3K and/or mTOR, as compared to their parental cells. These cells also showed profound resistance to drugs of other classes. Molecular analysis revealed persistent activation of phosphorylated AKT at threonine 308 in the drug resistant cells and increased expression of markers for tumor-initiating cells. Interestingly, increased intra-cellular ROS levels were observed in the drug resistant cells. Among anti-oxidant molecules, the expression of SOD2 was increased and was associated with the ALDH-positive tumor-initiating cell features. Co-incubation of SOD inhibitors and BEZ235 decreased the stemness feature of the cells in vitro, as shown by results of the spheroid formation assay. In conclusion, dysregulation of SOD2 might contribute to the profound resistance to PI3K inhibitors and the other drugs in HNC cells. [ABSTRACT FROM AUTHOR]

Background: Autophagy is reported as a survival or death-promoting pathway that is highly debatable in different kinds of cancer. Here, we examined the co-effect of cold atmospheric plasma (CAP) and silymarin nanoemulsion (SN) treatment on G-361 human melanoma cells via autophagy induction. Methods: The temperature and pH of the media, along with the cell number, were evaluated. The intracellular glucose level and PI3K/mTOR and EGFR downstream pathways were assessed. Autophagy-related genes, related transcriptional factors, and autophagy induction were estimated using confocal microscopy, flow cytometry, and ELISA. Results: CAP treatment increased the temperature and pH of the media, while its combination with SN resulted in a decrease in intracellular ATP with the downregulation of PI3K/AKT/mTOR survival and RAS/MEK transcriptional pathways. Co-treatment blocked downstream paths of survival pathways and reduced PI3K (2 times), mTOR (10 times), EGFR (5 times), HRAS (5 times), and MEK (10 times). CAP and SN co-treated treatment modulates transcriptional factor expressions (ZKSCAN3, TFEB, FOXO1, CRTC2, and CREBBP) and specific genes (BECN-1, AMBRA-1, MAP1LC3A, and SQSTM) related to autophagy induction. Conclusion: CAP and SN together activate autophagy in G-361 cells by activating PI3K/mTOR and EGFR pathways, expressing autophagy-related transcription factors and genes. [ABSTRACT FROM AUTHOR]

Lung cancer is the most prevalent cancer worldwide and non‑small cell lung cancer (NSCLC) is the most common subtype and accounts for 75% of all lung cancer cases. Although programmed death‑1/programmed death‑ligand‑1 (PD‑1/PD‑L1) blockade has shown good results in the clinic, numerous NSCLC patients still fail to respond to this therapy. In the current study, formalin‑fixed, paraffin‑embedded tumor and matched blood samples from 1,984 Chinese NSCLS patients were collected for detection of genomic alterations including single nucleotide variations, short and long insertions/deletions, copy number variations and gene rearrangements. The most common mutated genes were tumor protein p53 (55.70%; 1,105/1,984), epidermal growth factor receptor (52.47%; 1,041/1,184), KRAS proto‑oncogene GTPase (13.36%, 265/1084), cyclin dependent kinase inhibitor 2A (12.30%; 244/1,984), LDL receptor related protein 1B (11.09%; 220/1,984) and telomerase reverse transcriptase (10.58%; 210/1,984). Tumor mutational burden was calculated and results revealed that it was associated with PI3K/mTOR pathway gene mutations, and patient's gender, age, smoking status, and tumor stage. In addition, mutations of phosphatidylinositol‑4,5‑bisphosphate 3‑kinase catalytic subunit α or F‑box and WD repeat domain containing 7 were detected in 3 patients with NSCLC who were resistant to PD‑1 inhibitors nivolumab and pembrolizumab. Disease stabilization and tumor shrinkage were observed in these patients after mTOR inhibitor everolimus treatment. The current data showed that NSCLC with PI3K/mTOR mutations are sensitive to mTOR inhibitors.

Radiation therapy (RT) is the current standard adjuvant approach for oral squamous cell carcinoma (OSCC) patients. Radioresistance is a major contributor to radiotherapy failure. In this study, we used patient-derived cells and a radiation-resistant cell line in vitro and in vivo for two purposes: evaluate the anti-tumor effects and understand the mechanisms in the dual PI3K/mTOR signaling pathway regulation of radiosensitization. Our findings indicate that in OML1-R cells, the radioresistance phenotype is associated with activation of the PI3K/AKT/mTOR signaling pathway. Compared to a combination of PI3K or mTOR inhibitors and radiation, dual blockade of the PI3K and mTOR kinases significantly improved radiation efficacy in oral cancer and patient-derived OSCC cells. Dual PI3K/mTOR inhibition enhanced the effect of radiation by inhibiting AKT/mTOR signaling pathways and caused G1 phase arrest, which is associated with downregulation of cyclin D1/CDK4 activity, leading to growth inhibition. In nude mice xenografted with radioresistant OML1-R cells, the combined treatment was also more effective than RT alone in reducing tumor growth. This treatment was also demonstrated to be dependent on the inhibition of protein kinase-dependent S6 kinase pathway and eIF4E-mediated cap-dependent translation. These findings indicate that activation of the PI3K/AKT/mTOR signaling pathway has a role in radioresistance of OSCC. We determined that a PI3K/mTOR inhibitor combined with radiation exhibits synergistic inhibition of the AKT/mTOR axis and induces cell cycle arrest. Our results show the therapeutic potential of drugs targeting the PI3K/AKT/mTOR signaling pathway should be new candidate drugs for radiosensitization in radiotherapy., Competing Interests: CONFLICTS OF INTEREST Nothing to declare.

The aim of this study was to clarify the synergistic effects of dual inhibition of the PI3K/mTOR and MAPK pathways in ovarian mucinous carcinoma (OMC) cells, using fluorescence resonance energy transfer (FRET) imaging. We exposed 6 OMC cell lines to a PI3K/mTOR inhibitor (voxtalisib, SAR245409) and/or a MEK inhibitor (pimasertib), and evaluated synergistic effects using the Chou-Talalay method. Then, S6K (PI3K pathway) and ERK (MAPK pathway) kinase activities, and their individual proliferative or cytotoxic effects were calculated by time-lapse FRET imaging. In combination with SAR245409, pimasertib (30 nM) synergistically inhibited cell growth (combination indexes: 0.03-0.5) and induced apoptosis in all 6 OMC cell lines. FRET-imaging results demonstrated that ERK inhibition induced both anti-proliferation and apoptosis in a dose-dependent manner in both MCAS and OAW42 cells. However, S6K inhibition suppressed proliferation in a threshold manner in both cell lines, although apoptosis was only induced in OAW42 cells. These results demonstrated that combined PI3K/mTOR and MEK inhibition exhibited synergistic antitumor effects in OMC cells and that FRET imaging is useful for analyzing kinase activities in live cells and elucidating their cytostatic and cytotoxic effects., Competing Interests: The authors report no conflicts of interest.

Aim: Endometrial stromal sarcoma (ESS) is a rare gynecological mesenchymal malignancy with only few therapeutic options. This study aimed to investigate the efficacy of the histone deacetylase (HDAC) inhibitor suberanilohydroxamic acid (SAHA) combined with inhibitors of the phosphoinositid-3-Kinase (PI3K) pathway in ESS therapy., Materials and Methods: The effects of SAHA combined with inhibitor of PI3K (LY294002, LY), mammalian target of rapamycin mTOR (rapamycin), and their combination on cell growth and the PI3K pathway in two ESS cell lines (ESS-1 and MES-SA) and one non-neoplastic cell line HESC, were investigated., Results: SAHA reduced growth of the three cell lines by inhibiting protein kinase B AKT and mTOR/p70S6K cascade activation. SAHA combined with LY or rapamycin, or both, synergistically reduced p-p70S6K and p-4E-BP1 levels. SAHA combined with LY and rapamycin led to the strongest growth inhibition and slowest growth recovery among the combination treatments., Conclusion: SAHA combined with inhibition of PI3K and mTOR could represent an efficient therapy option for patients with ESS., (Copyright© 2014 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.)

Breast cancer is the most common cancer among women. Up to 75% of breast cancers express the estrogen receptor (ER)α and/or the progesterone receptor (PR). Patients with hormone receptor-positive metastatic breast cancer are typically treated with endocrine therapy. Yet, not all patients with metastatic breast cancer respond to endocrine treatments and are considered to have primary (de novo) resistance. Furthermore, all patients who initially respond to endocrine treatment will eventually develop acquired resistance. Several mechanisms have been linked to the development of endocrine resistance, including reduced expression of ERα, altered regulation of the ER pathway, and activation of various growth factor signaling pathways, among them the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of rapamycin (mTOR) signaling pathway. This pathway is involved in critical processes including cell survival, proliferation, and angiogenesis, and plays a central role in breast cancer development. Recent laboratory and clinical data implicate this pathway as mediating endocrine resistance, and agents directed against critical components of this pathway are either already approved for clinical use in breast cancer patients or are currently being tested in clinical trials. In this review, we describe the interaction between the PI3K/Akt/mTOR pathway and the ER cascade, its role in mediating endocrine resistance, and the clinical implications of this interaction.