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Activation of the cellular signaling pathways can induce sorafenib-resistant hepatocellular carcinoma (HCCR). In this work, the PI3K/mTOR inhibitor GSK1059615 inhibited the proliferation and invasion of HCCR cells. PLGA-PEG-mal diblock copolymer was used to load GSK1059615 and sorafenib, and the vector was further modified with GPC3 antibody (hGC33) to obtain hGC33-modified GSK1059615 and sorafenib-loaded nanoparticles (Ab-G/S-NP). Ab-G/S-NP regulated the activation of cellular signaling pathways in HCCR cells by inhibiting the expression and activation of NF-κB and downregulating the level of programmed cell death 1 ligand 1(PD-L1) to reverse drug resistance of HCCR cells to sorafenib. These findings deserve further study in the combined treatment of HCCR cells with GSK1059615 in vivo to develop a more effective treatment of sorafenib-resistant cancers.

Lanyu Lu,1 Bowei Liu,2 Yongfang Ma3 1Department of Endocrinology and Metabolic Diseases, Hebei Medical University, Shijiazhuang, Hebei, People’s Republic of China; 2Department of Endocrinology, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei, People’s Republic of China; 3Department of Internal Medicine, Chengde Medical University, Chengde, Hebei, People’s Republic of ChinaCorrespondence: Bowei Liu, Department of Endocrinology, The First Hospital of Qinhuangdao, Qinhuangdao, Hebei, People’s Republic of China, Tel/Fax +86-335-5908603, Email liubo-wei@126.comPurpose: To investigate the relationship between different obesity phenotypes and sarcopenia in hospitalized Chinese patients with type 2 diabetes mellitus (T2DM).Methods: This cross-sectional study included 385 men. Anthropometric measurements including applied the determination method of Dual-energy X-ray absorptiometry (DXA) determination of limb skeletal muscle mass index (ASMI) and blood samples were analyzed. The people were divided into four groups according to body mass index (BMI) (≥ 24kg/m2) and waist circumference (WC) (female ≥ 85cm, male ≥ 90cm). Group A (BMI and WC were normal), Group B (BMI was normal and high WC), Group C (high BMI and WC were normal), and Group D (BMI and WC were abnormal).Results: The prevalence rates of sarcopenia and abdominal obesity were 32.2% and 74.0%, respectively. The detection rate of lower ASMI decreased gradually from Group A to Group D(74.6% vs 68.3% vs 54.5% vs 51.6%, χ 2 =14.243, P=0.003). Logistic analysis showed that the risk of lower ASMI were decreased by 62.4% (95% CI: 0.149– 0.950, P = 0.039) in Group C and 68.8% (95% CI: 0.165– 0.593, P = 0.000) in Group D compared with Group A, respectively. The risk of lower ASMI were increased 4.153-fold (95% CI: 2.623– 6.576, P = 0.000) in male. Male (OR = 4.065, 95% CI: 2.246– 7.356, P = 0.000) and WC (OR = 1.053, 95% CI: 1.004– 1.104, P = 0.033) were risk factors for lower ASMI, but the risk of lower ASMI was decreased by 32% (95% CI: 0.5744– 0.804, P = 0.000) by elevated BMI in the overweight and obese group (Group C and Group D).Conclusion: The prevalence of sarcopenia and abdominal obesity was elevated in han Chinese middle-aged and elderly patients with T2DM. Being overweight or obesity as defined by BMI protect against sarcopenia, while abdominal obesity increases the risk of sarcopenia.Keywords: T2DM, sarcopenia, ASMI, BMI, WC

Objective: To investigate the association between plasma irisin and impaired glucose regulation (IGR) among Chinese young men. Materials and Methods: This cross-sectional study involved 86 Chinese male subjects, aged 18-45 years, who visited the First Hospital of Qinhuangdao (Hebei, China) in 2017 for annual health check-up. Anthropometric measurements, including height, weight and waist circumference (WC) were performed. All patients underwent an oral glucose tolerance test (OGTT) after 8 hours of fasting, and the levels of glucose, insulin, lipids and serum irisin were measured. Participants were categorized into: normal glucose tolerance (NGT) [fasting plasma glucose (FPG)＜5.6 mmol/L, and 2-h plasma glucose (2hPG) ＜7.8 mmol/L after a 75-g OGTT]; IGR[impaired fasting glucose (IFG) ( 5.6mmol/l ≤FPG＜7.0 mmol/L, and 2hPG＜7.8 mmol/L ) and impaired glucose tolerance (IGT) (FPG＜5.6 mmol/L, and 7.8 mmol/l ≤2hPG＜11.1 mmol/L]. Results: Subjects in the IGR group had higher body mass index (BMI), WC, FPG, 2hPG and homeostasis model assessment of insulin resistance (HOMA-IR), and lower high-density lipoprotein cholesterol(HDL-C) than subjects in the NGT group (P < 0.05). The levels of serum irisin (4.43 ± 1.44 vs. 6.25 ± 1.46 µg/mL) were significantly lower in the IGR group (PP P= 0.000) and HOMA-IR (OR=5.586, P = 0.011) were independent risk factors for predicting IGR. Conclusions: Serum irisin levels were reduced in Chinese young men with IGR. Reduced irisin may increase the occurrence of IGR. It suggested that irisin may predict the occurrence of impaired glucose homeostasis and should be examined in future studies.

Selenium is an essential trace element in the human body. The significant action of selenium is based on the selenium-containing protein as a mediator. Of note, previous studies reported that the expression of selenium-binding protein 1 (SELENBP1) has obviously decreased in many human cancer tissues including non-small-cell lung cancer (NSCLC). However, its roles in the origin and development of NSCLC are still unclear. Here, we further identified that the expression of SELENBP1 was dramatically decreased in NSCLC tissues in the TCGA database and 45 out of 59 collected clinical NSCLC tissues compared with adjacent nontumor tissues as well as four NSCLC cell lines compared with normal lung cells. Then a series of in vitro experiments uncovered that overexpression of SELENBP1 markedly inhibited the proliferation, migration, and invasion of NSCLC cells and induced cell apoptosis. Moreover, overexpression of SELENBP1 also observably inhibited growth and induced apoptosis of NSCLC cells in vivo. Mechanistically, we demonstrated that overexpression of SELENBP1 inhibited the malignant characteristics of NSCLC cells via inactivating the PI3K/AKT/mTOR signal pathway. Meanwhile, we found that overexpression of SELENBP1-inducing apoptosis of NSCLC cells was associated with the activation of the caspase-3-dependent signaling pathway under nonhigh levels of oxidative stress, but overexpression of SELENBP1 facilitating the cell apoptosis was related to its combining with GPX1 and colocalizing in the nucleus under high levels of oxidative stress. Particularly, we unexpectedly discovered that SELENBP1 was obviously expressed in alveolar type 2 (AT-II) cells for the first time. Collectively, our findings highlighted that SELENBP1 was an important tumor suppressor during the origin and development of NSCLC. It may help to discover novel biomarkers or drug therapy targets for NSCLC.

The objective of this work is to develop and verify the analytical performance of a chemiluminescence immunoassay for the specific sequence β-carboxy-terminal cross-linking telopeptide of type I collagen (β-CTX) in human serum. Two specific monoclonal antibodies (mAb-8A03 and mAb-3D12) with high affinity for β-CTX were selected, and, under optimized conditions, a chemiluminescence immunoassay method (CLIA) for β-CTX was established. The CLIA of β-CTX detected β-CTX in a wide range of 2.0-6000 ng/L. The recovery rate in serum is 95-105%, the specificity is high, and the cross-reaction rate with common easily interfering substances is low (not more than 0.01%). The CLIA correlates well with Roche electrochemiluminescence immunoassay (ECLIA), with a correlation coefficient of 0.9551, which fully meets the requirements of clinical analysis. The developed β-CTX CLIA kit has high sensitivity and good stability. It has the same performance as the commercial Roche ECLIA kit and can be applied clinically.

Epithelial mesenchymal transition (EMT) and inflammation have been identified as carcinogenic agents. This study aims to investigate whether inhibition of trichloroethylene (TCE) associated hepatocellular carcinoma (HCC) by curcumin is associated with inflammation and EMT.In the current study, TCE sub-chronic cell model was inducedTCE induces hepatocyte migration, colony formation, and EMTCurcumin has anti-inflammatory and anti-proliferative effects, and inhibits the development of HCC induced by TCE by reversing IL-6/STAT3 mediated EMT.

The miR let-7b-5p (a kind of microRNAs) has many pathophysiological regulation effects, including human hepatocellular carcinoma (HCC) pathogenesis. This study investigated whether nanoparticle-mediated miR let-7b-5p could jointly enhance the therapeutic effect of sorafenib on HCC by inhibiting the proliferation of HCC cells, inducing apoptosis, and reversing drug resistance. We evaluated the level of miR let-7b-5p in sorafenib-resistant HepG2 cells (HepG2R) and HepG2 HCC cells by qRT-PCR and analyzed the biological effects of hepatocellular carcinoma treated with sorafenib with miR let-7b-5p, and further studied the toxicity of nanoparticles (Ab-miR-NPs) that deliver miR let-7b-5p mimics and target GPC3 on the surface of hepatocellular carcinoma cells. Results showed that, in HepG2 cells, the expression level of miR let-7b-5p was significantly higher than that in HepG2R cells. Targeted nanoparticle Ab-miR-NPs mediated the delivery of miR let-7b-5p to the HCC cytoplasm and released miRNA after being broken down, down-regulating the expression of IGF1R and inhibiting AKT/mTOR and Ras/Raf signal transmission. Ab-miR-NPs not only enhanced the proliferation of sorafenib in cultured HepG2R cells and induced cell apoptosis efficiency, but they also improved the anti-tumor activity in the mouse models. These results indicated that GPC3 antibody-modified PLGA-PLL (polylactic acid-glycolic acetic copolymer grafted hyper-branched polylysine) loaded miR let-7b-5p polymer nanoparticles combined with sorafenib may be a new treatment strategy for HCC resistant to sorafenib.

Background Gefitinib is a first-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) that has become first-line treatment for patients with mutant EGFR non-small cell lung cancer (NSCLC). Despite its anti-tumor activity, the benefit of gefitinib in patients with wild-type EGFR NSCLC is debated. This work aimed to evaluate the effects of gefitinib on cisplatin-resistant wild-type EGFR NSCLC cells in in vitro and in vivo animal xenografts. Methods We established a cisplatin-resistant wild-type EGFR NSCLC cell line, H358R, to evaluate the cells’ sensitivity to gefitinib compared with that of parental cell line H358. We first tested the p-EGFR of gefitinib’s target in H358R and H358 cell line by western blot and immunofluorescence. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), clone formation assay, flow cytometry and annexin V-fluorescein/propidium iodide staining were used to investigate cellular proliferation and apoptosis of H358R/H358 cells treated with gefitinib, and the anti-tumor effect was evaluated in female BALB/c nude mice models of xenografts in vivo. Results EGFR and the downstream node molecules ERK and AKT were significantly more phosphorylated in H358R than in the parental cells and were inhibited by gefitinib. In H358R cells, gefitinib increased the inhibition of cell survival/proliferation, and the promotion of apoptosis in vitro. The increased anti-tumor effect was present also in H358R xenografts in vivo. Conclusions Abnormal activation of EGFR in H358R cells results in enhanced sensitivity to gefitinib. The improved efficacy of gefitinib on cisplatin-resistant wild-type EGFR NSCLC cells suggests that gefitinib as sequential therapy for patients with cisplatin-resistant wild-type EGFR NSCLC should be considered.

The usual first-line strategy of wild-type EGFR (wtEGFR) non-small cell lung cancer (NSCLC) remains cisplatin-based chemotherapy. However, cisplatin often loses effectiveness because most tumors acquire drug resistance over time. As EGFR is the most important pro-survival/proliferation signal receptor in NSCLC cells, we aimed at investigating whether cisplatin resistance is related to EGFR activation and further evaluating the combined effects of cisplatin/gefitinib (EGFR-tyrosine kinase inhibitor, EGFR-TKI) on cisplatin-resistant wtEGFR NSCLC cells. EGFR activation was analysed in parental and cisplatin-resistant wtEGFR NSCLC cell lines (H358 and H358R, A549 and A549R). Cellular proliferation and apoptosis of H358R/A549R cells treated with cisplatin or gefitinib, alone or in combination were investigated, and the related effector protein was detected by western blot analysis. Anti-tumor effect of two drugs combined was evaluated in animal models of H358R xenografts in vivo. EGFR was significantly phosphorylated in cisplatin-resistant wtEGFR NSCLC cells H358R and A549R than their parental cells. In H358R and A549R cells, anti-proliferative ability of gefitinib was further improved, and gefitinib combined with cisplatin enhanced inhibition of cellular survive/proliferation, and promotion of apoptosis in vitro. The combined effects were also associated with the inhibition of EGFR downstream effector proteins. Similarly, in vivo, gefitinib and cisplatin in combination significantly inhibited tumor growth of H358R xenografts. Abnormal activation of EGFR may induce wtEGFR NSCLC cell resistance to cisplatin. The combined effects of cisplatin/gefitinib suggest that gefitinib, as a combination therapy for patients with cisplatin-resistant wtEGFR NSCLC should be considered.

The transgenerational effect assessment linked to epigenetic analysis of environmental pollutants on eco (toxico)logical relevant species is regarded as a potential future risk-assessment tool. As an organotin acaricide widely used in China, azocyclotin can lead to endocrine disrupting effect on directly exposed environmental organisms, but whether it has transgenerational negative impact remains unknown. In order to illustrate this issue, in the present study, zebrafish, an aquatic model animal, was exposed to azocyclotin at less than μg/L level in a time span of embryonic stage to adult stage. Subsequently, the developmental and reproductive endocrine disrupting effects of azocyclotin on exposed F0 and unexposed offspring (F1 and F2) were evaluated. Result indicated that parentally exposed to 0.36 μg/L azocyclotin induced embryonic toxicity to unexposed offspring, and significantly (p 0.05) reduced body weight (by 8.5%-13.9%), whole body length (by 4.8%-14.3%), hepatosomatic index (by 15.6%-24.3%), gonadosomatic index (by 5.3%-17.1%), egg production (by 19.5%-25.4%), estradiol content (47.0%-65.0%) and proportion of mature germ cells (by 29.3%-41.0% and 39.2%-47.7% for late oocytes and spermatozoa, respectively) in adults of F0 and offspring. Additionally, azocyclotin decreased the contents of 5-methycytosine in gonads of unexposed offspring (by 9.9%-38.6%, p 0.05), led to genome-wide gene up-regulated expression bias and genomic DNA hypomethylation tendency in unexposed offspring. Moreover, based on the level of differentially methylated cytosine in promoter regions/gene body regions, it was found totally 5331/11,170 (in F1) and 3808/7507 (in F2) differentially expressed genes were closely related with differentially methylated genes (r 0.6). The present study provided a primary evidence that prolonged exposure to low dose azocyclotin induced inter- and transgenerational endocrine disrupting effects on zebrafish probably linked to transcriptomic and DNA methylomic alterations.

Deltamethrin (DM), a type II pyrethroid insecticide, is widely used to control agricultural pests. However, its excessive use exerts a detrimental effect on the ecological environment and human health, indicating the need to study its potential risks in detail. In the present study, zebrafish embryos were exposed to varying concentrations of DM (0.1, 1, 10, and 25 μg/L) for 96 h to assess the alterations in the transcript levels of proteins of the estrogenic and dopaminergic pathways. In addition, its effect on zebrafish locomotor activity was studied. The mRNA expression of cyp19a1b, erα, erβ2, fshr, gnrh2, gnrhr3, vtg3, dat, and dr1 significantly changed after exposing the embryos to DM. Deltamethrin at 10 and 25 μg/L significantly reduced the average swimming speed of zebrafish larvae. In addition, embryos injected with zebrafish estrogen receptor α (erα) and β (erβ) morpholinos and co-exposed to 25 μg/L DM for 96 h showed reduced expression of vtg3 mRNA compared to embryos exposed to 25 μg/L DM only. The locomotor activity of erα and erβ knockdown zebrafish following DM exposure was increased significantly when compared with that of larvae exposed to 25 μg/L DM only. Our results demonstrated that DM altered the locomotor activity of zebrafish larvae and the transcript levels of the components of estrogenic and dopaminergic pathways; erα and erβ knockdown weakened these effects.

Liver cancer remains one of the leading causes of cancer deaths worldwide. The therapeutic effect of oxaliplatin on liver cancer is often limited by acquired resistance of the cancer cells. Abnormal activation of the PI3K/AKT pathway plays an important role in the acquired resistance of oxaliplatin. The present study investigated the effects of the PI3K inhibitor LY-294002 and AKT inhibitor MK2206 on the chemosensitivity of oxaliplatin-resistant liver cancer cells and the molecular mechanism involved. An oxaliplatin-resistant liver cancer cell line HepG2R was developed. MTT assay, clone formation experiments, flow cytometry and Annexin V-FITC/PI staining were used to determine the proliferation, cycle and apoptosis of HepG2R cells when oxaliplatin was combined with LY-294002 or MK2206 treatment. The effects of LY-294002 and MK-2206 on the abnormal activation of PI3K/AKT pathway and hypoxia inducible factor (HIF)-1α protein level in HepG2R cells were detected using western blotting. The results indicated that the PI3K/AKT pathway is stably activated in HepG2R cells. Compared with the AKT inhibitor MK2206, the PI3K inhibitor LY-294002 more effectively downregulated the phosphorylation levels of p85, p110α, p110β, p110γ and AKT in the PI3K/AKT pathway in HepG2R cells, and more effectively inhibited the proliferation of the cells. LY-294002 enhanced the chemotherapy sensitivity of HepG2R cells to oxaliplatin by inducing G0/G1 phase arrest and increasing the proportion of apoptotic cells. In addition, LY-294002 reduced the level of HIF-1α, which is highly expressed in HepG2R cells. It was concluded that LY-294002 enhanced the chemosensitivity of liver cancer cells to oxaliplatin by inhibiting the PI3K/AKT signaling pathway, which may be related to the inhibition of HIF-1α expression. These findings may have clinical significance for the treatment of oxaliplatin-resistant liver cancer.

Acquired resistance of hepatocellular carcinoma (HCC) to sorafenib (SFB) is the main reason for the failure of SFB treatment of the cancer. Abnormal activation of the PI3K/AKT/mTOR pathway is important in the acquired resistance of SFB. Therefore, we investigated whether BEZ235 (BEZ) could reverse acquired sorafenib resistance by targeting the PI3K/mTOR pathway. A sorafenib-resistant HCC cell line Huh7R was established. MTT assay, clone formation assay, flow cytometry, and immunofluorescence were used to analyze the effects of BEZ235 alone or combined with sorafenib on cell proliferation, cell cycle, apoptosis, and autophagy of Huh7 and Huh7R cells. The antitumor effect was evaluated in animal models of Huh7R xenografts in vivo. Western blot was used to detect protein levels of the PI3K/AKT/mTOR pathway and related effector molecules. In vitro results showed that the Huh7R had a stronger proliferation ability and antiapoptosis effect than did Huh7, and sorafenib had no inhibitory effect on Huh7R. SFB + BEZ inhibited the activation of the PI3K/AKT/mTOR pathway caused by sorafenib. Moreover, SFB + BEZ inhibited the proliferation and cloning ability, blocked the cell cycle in the G0/G1 phase, and promoted apoptosis in the two cell lines. The autophagy level in Huh7R cells was higher than in Huh7 cells, and BEZ or SFB + BEZ further promoted autophagy in the two cell lines. In vivo, SFB + BEZ inhibited tumor growth by inducing apoptosis and autophagy. We concluded that BEZ235 enhanced the sensitivity of sorafenib through suppressing the PI3K/AKT/mTOR pathway and inducing autophagy. These observations may provide the experimental basis for sorafenib combined with BEZ235 in trial treatment of HCC.

Delivery of tumor-specific inhibitors is a challenge in cancer treatment. Antibody-modified nanoparticles can deliver their loaded drugs to tumor cells that overexpress specific tumor-associated antigens. Here, we constructed sorafenib-loaded polyethylene glycol-b-PLGA polymer nanoparticles modified with antibody hGC33 to glypican-3 (GPC3 +), a membrane protein overexpressed in hepatocellular carcinoma. We found that hGC33-modified NPs (hGC33-SFB-NP) targeted GPC3+ hepatocellular carcinoma (HCC) cells by specifically binding to GPC3 on the surface of HCC cells, inhibited Wnt-induced signal transduction, and inhibited HCC cells in G0/1 by down-regulating cyclin D1 expression, thus attenuating HCC cell migration by inhibiting epithelial–mesenchymal transition. hGC33-SFB-NP inhibited the migration, cycle progression, and proliferation of HCC cells by inhibiting the Ras/Raf/MAPK pathway and the Wnt pathway in tandem with GPC3 molecules, respectively. hGC33-SFB-NP inhibited the growth of liver cancer in vivo and improved the survival rate of tumor-bearing mice. We conclude that hGC33 increases the targeting of SFB-NP to HCC cells. hGC33-SFB-NP synergistically inhibits the progression of HCC by blocking the Wnt pathway and the Ras/Raf/MAPK pathway.

Aim: To assess AB-BEZ235-NP potential as a radio-sensitizer in hepatocellular carcinoma models. Method: By comparing hepatocellular carcinoma cell with simple radiation or combined AB-BEZ235-NP therapy, the HCC apoptosis and self-repair level have significant differences in mortality rates and cell migration abilities. Results: Cell proliferation and DNA damage increased by pretreatment with AB-BEZ235-NP after irradiation; further studies on the repair pathway indicated that AB-BEZ235-NP inhibited the important pathway of DSB repair. Our results further show that AB-BEZ235-NP significantly inhibits the phosphorylation of the canonical protein, γ-H2AX, in the NHEJ DSB repair pathway and Serine Protein Kinase (SPK) ATM, and TP53-Binding Protein one. More importantly, AB-BEZ235-NP increased the mount of mean γ-H2AX Foci in irradiated cells, indicating that AB-BEZ235-NP can selectively inhibit DSB repair in HCC cells. Therefore, these results clearly eludicate that treatment with AB-BEZ235-NP is a potential promising therapy which can increase the radiosensitivity to HCC.

Background: Sorafenib, an oral multi-kinase inhibitor of rapidly accelerated fibrosarcoma; vascular endothelial growth factor receptor-2/3, platelet-derived growth factor receptor, c-Kit, and Flt-3 signaling, is approved for treatment of advanced hepatocellular carcinoma (HCC). However, the benefit of sorafenib is often diminished because of acquired resistance through the reactivation of ERK signaling in sorafenib-resistant HCC cells. In this work, we investigated whether adding LY3214996, a selective ERK1/2 inhibitor, to sorafenib would increase the anti-tumor effectiveness of sorafenib to HCC cells. Methods: The Huh7 cell line was used as a cell model for treatment with sorafenib, LY3214996, and their combination. Phosphorylation of the key kinases in the Ras/Raf/MAPK and PI3K/Akt pathways, protein expression of the cell cycle, and apoptosis migration were assessed with western blot. MTT and colony-formation assays were used to evaluate cell proliferation. Wound-healing assay was used to assess cell migration. Cell cycle and apoptosis analyses were conducted with flow cytometry. Results: LY3214996 decreased phosphorylation of the Ras/Raf/MAPK and PI3K/Akt pathways, including p-c-Raf, p-P90RSK, p-S6K and p-eIF4EBP1 activated by sorafenib, despite increased p-ERK1/2 levels. LY3214996 increased the anti-proliferation, anti-migration, cell-cycle progression, and pro-apoptotic effects of sorafenib on Huh7R cells. Conclusions: Reactivation of ERK1/2 appears to be a molecular mechanism of acquired resistance of HCC to sorafenib. LY3214996 combined with sorafenib enhanced the anti-tumor effects of sorafenib in HCC. These findings form a theoretical basis for trial of LY3214996 combined with sorafenib as second-line treatment of sorafenib-resistant in advanced HCC.

Radiotherapy remains one of the major treatments for non-small cell lung cancer (NSCLC) patients; whereas intrinsic or acquired radioresistance limits its efficacy. Nevertheless, most studies so far have only focused on acquired resistance. The exact mechanisms of intrinsic radioresistance in NSCLC are still unclear. A few studies have suggested that epithelial–mesenchymal transition (EMT) is associated with radioresistance in NSCLC. However, little is known about whether the abnormal expression of specific microRNAs induces both EMT and radioresistance. We previously found that miR-410 has multiple roles as an oncomiRNA in NSCLC. In this study, we revealed that miR-410 overexpression promoted EMT and radioresistance, accompanied by enhanced DNA damage repair both in vitro and in vivo. Conversely, knockdown of miR-410 showed the opposite effects. We further demonstrated that PTEN was a direct target of miR-410 by using bioinformatic tools and dual-luciferase reporter assays, and the miR-410-induced EMT and radioresistance were reversed by PI3K, Akt, and mTOR inhibitors or by restoring the expression of PTEN in NSCLC cells. In addition, we preliminarily found that the expression of miR-410 was positively correlated with EMT and negatively associated with the expression of PTEN in NSCLC specimens. In summary, these results demonstrated that miR-410 is an important regulator on enhancing both NSCLC EMT and radioresistance by targeting the PTEN/PI3K/mTOR axis. The findings suggest that miR-410-induced EMT might significantly contribute to the enhanced radioresistance. Therefore, miR-410 may serve as a potential biomarker or therapeutic target for NSCLC radiotherapy.

Oxaliplatin resistance limits its effectiveness in the treatment of hepatocellular carcinoma (HCC). Abnormal activation of the PI3K/AKT/mTOR pathway has been associated with decreased survival of HCC patients, anti-apoptosis after chemotherapeutic drug-induced DNA damage, and chemoresistance. In this research, we evaluated the effect of the dual PI3K/mTOR inhibitor, PKI-587, on the sensitivity of oxaliplatin in HCC. Two HCC cell lines (HepG2 and SK-Hep1) were used to analyze PKI-587 for DNA damage response, cell proliferation, clonogenic survival, cell cycle and apoptosis after oxaliplatin treatment. A HepG2 tumor-bearing model was used to assess the in vivo effects of the combination of the two compounds. In HCC cells, oxaliplatin stably activated the PI3K/AKT/mTOR pathway, including up-regulation of p-Akt (Ser473), p-mTOR (Ser2448), p-mTOR (Ser2481), p-elF4EBP1, and p-S6K1, and activated the DNA damage repair pathways (non-homologous end joining (NHEJ) and homologous recombination (HR)), up-regulation of p-DNAPKcs (Ser2056), p-ATM (Ser1981), and p-ATR (Ser428), which were attenuated by PKI-587. Compared with oxaliplatin alone, the combination of PKI-587 and oxaliplatin increased the number of γ-H2AX/cells, decreased proliferation of cells, and an increased the percentage of G0/G1 phase cells and apoptotic cells. In vivo, the combination of oxaliplatin with PKI-587 inhibited tumor growth. Anti-tumor effects were associated with induction of mitochondrial apoptosis and inhibition of phosphorylation of mTOR, Akt and γ-H2AX. We conclude that PKI-587 enhances chemosensitivity of oxaliplatin in HCC through suppressing the PI3K/AKT/mTOR signalling pathway and inhibiting the DNA damage repair pathway. The combination of PKI-587 and oxaliplatin appears to be a promising regimen for the treatment of HCC.

Background: Sorafenib is an oral multi-kinase inhibitor that inhibits hepatocellular carcinoma (HCC) via the Ras/Raf/MAPK pathway. However, sorafenib loses effectiveness because most tumors acquire drug resistance over time. As the PI3K/AKT/mTOR signaling pathway is also activated abnormally in HCC, we evaluated the effect of sorafenib, in combination with a dual PI3K/mTOR inhibitor, BEZ235, on HCC cell proliferation and survival in vitro. Materials and methods: Biological phenotypes were analysed in HCC cell lines, parental and sorafenib-resistant HepG2 cells (HepG2 and HepG2(R)), treated with sorafenib or BEZ235, alone or in combination. HCC cellular proliferation and apoptosis were investigated, and perturbations of the Ras/Raf/MAPK and PI3K/AKT/mTOR signaling/survival pathways were evaluated by western blot analysis. Results: BEZ235 enhanced sorafenib inhibition of cellular proliferation, migration, and promotion of apoptosis in HepG2 and HepG2(R) cells. The combined effects were associated with inhibition of phosphorylation of AKT, mTOR and S6K in the PI3K/AKT/mTOR pathway, whereas the combination of sorafenib and BEZ235 did not significantly alter the Ras/Raf/MAPK pathway compared with the effect of sorafenib alone. Conclusion: Sorafenib/BEZ235 combination has potent anti-HCC cell activity. This anti-tumor activity is most likely multi-factorial, mainly involving PI3K down-regulation and AKT, mTOR and S6K dephosphorylation. Combined inhibition of PI3K/AKT/mTOR and Ras/Raf/MAPK pathways enhances sorafenib inhibition of HCC. The results of these in vitro studies suggest that trials of combined sorafenib and BEZ235 in the treatment of HCC should be considered.