Celecoxib regulates apoptosis and autophagy via the PI3K/Akt signaling pathway in SGC-7901 gastric cancer cells

Alkaloids from Zanthoxylum nitidum and their anti-proliferative activity against A549 cells by regulating the EGFR/AKT/mTOR pathway

Zanthoxylum nitidum is frequently used as a traditional Chinese medicine and food supplement. Our previous study revealed that its constituent compounds were able to inhibit cancer cell proliferation. In our continuous exploration of bioactive compounds in Z. nitidum, we isolated ten alkaloids (1-10), including one new natural compound (1), and nine known alkaloids (2-10), from an ethanolic extract of the whole plant. The chemical structures were elucidated based on a combination of comprehensive NMR and HRESIMS analyses. Compounds 5, 8 and 10 exhibited significant antiproliferative effects against A549 cancer cell lines. We further elucidated the underlying molecular mechanisms of the antiproliferative activity of compound 8 in A549 human lung cancer cells. Compound 8 was found to induce cell cycle arrest in the G0/G1 phase via p53 activation and CDK4/6 suppression. Compound 8 also effectively inhibited cell migration through the modulation of the epithelial-mesenchymal transition (EMT), as indicated by the expression of biomarkers, such as N-cadherin downregulation and E-cadherin upregulation. Compound 8 significantly suppressed the activation of the EGFR/AKT/mTOR signalling pathway in A549 cells. These results indicate that alkaloid 8 from Z. nitidum has potential to be a lead antiproliferative compound in cancer cells.

Celecoxib alleviates the DSS-induced ulcerative colitis in mice by enhancing intestinal barrier function, inhibiting ferroptosis and suppressing apoptosis

INTRODUCTION

Ulcerative colitis (UC) is an inflammatory intestine disease characterized by dysfunction of the intestinal mucosal barrier, ferroptosis, and apoptosis. Previous researches suggest that celecoxib, a nonsteroidal anti-inflammatory drug, holds promise in alleviating inflammation in UC. Therefore, this study aims to investigate the effects and mechanisms of celecoxib in UC.

METHODS

To identify ferroptosis-related drugs and genes associated with UC, we utilized the Gene Expression Omnibus (GEO), FerrDb databases, and DGIdb database. Subsequently, we established a 2.5% DSS (Dextran sulfate sodium)-induced colitis model in mice and treated them with 10 mg/kg of celecoxib to validate the bioinformatics results. We evaluated histological pathologies, inflammatory response, intestinal barrier function, ferroptosis markers, and apoptosis regulators.

RESULTS

Celecoxib treatment significantly ameliorated DSS-induced UC in mice, as evidenced by the body weight change curve, colon length change curve, disease activity index (DAI) score, and histological index score. Celecoxib treatment reduced the level of pro-inflammatory factors and promoted the expressions of intestinal tight junction proteins such as Claudin-1 and Occludin, thereby restoring the integrity of the intestinal mucosal barrier. Furthermore, celecoxib treatment reversed the ferroptosis characteristics in DSS-induced mice by increasing glutathione (GSH), decreasing malondialdehyde (MDA), and increasing the expression of GPX-4 and xCT. Additionally, apoptosis was induced in mice with UC, as evidenced by increased Caspase3, BAD, P53, BAX, Caspase9 and Aifm1 production, and decreased expression of BCL-XL and BCL2. Celecoxib treatment significantly reversed the apoptotic changes in DSS-induced mice.

CONCLUSION

Our findings suggest that celecoxib effectively treats DSS-induced UC in mice by inhibiting ferroptosis and apoptosis.

Chronic inflammation and cancer; the two sides of a coin

The correlation between chronic inflammation and cancer was initially identified in the 19th century. Biomolecules like interleukins, chemokines, tumor necrosis factors, growth factors, and adhesion molecules, which regulate inflammation, are recognized contributors to neoplastic transformation through various mechanisms, including oncogenic mutations, resistance to apoptosis, and adaptive responses like angiogenesis. This review aims to establish connections between the intricate and complex mechanisms of chronic inflammation and cancer. We illuminate implicit signaling mechanisms that drive the association between chronic inflammation and the initiation/progression of cancer, exploring potential impacts on other diseases. Additionally, we discuss the modalities of currently available therapeutic options for chronic inflammation and cancer, emphasizing the dual nature of such therapies. A thorough understanding of the molecular basis of chronic inflammation is crucial for developing novel approaches in the prevention and treatment of cancer.

Drug Repurposing in Non-Small Cell Lung Carcinoma: Old Solutions for New Problems

Lung cancer is the second most common cancer and the leading cause of cancer-related deaths in 2022. The majority (80%) of lung cancer cases belong to the non-small cell lung carcinoma (NSCLC) subtype. Despite the increased screening efforts, the median five-year survival of metastatic NSCLC remains low at approximately 3%. Common treatment approaches for NSCLC include surgery, multimodal chemotherapy, and concurrent radio and chemotherapy. NSCLC exhibits high rates of resistance to treatment, driven by its heterogeneity and the plasticity of cancer stem cells (CSCs). Drug repurposing offers a faster and cheaper way to develop new antineoplastic purposes for existing drugs, to help overcome therapy resistance. The decrease in time and funds needed stems from the availability of the pharmacokinetic and pharmacodynamic profiles of the Food and Drug Administration (FDA)-approved drugs to be repurposed. This review provides a synopsis of the drug-repurposing approaches and mechanisms of action of potential candidate drugs used in treating NSCLC, including but not limited to antihypertensives, anti-hyperlipidemics, anti-inflammatory drugs, anti-diabetics, and anti-microbials.

Immune Pathway and Gene Database (IMPAGT) Revealed the Immune Dysregulation Dynamics and Overactivation of the PI3K/Akt Pathway in Tumor Buddings of Cervical Cancer

Tumor budding (TB) is a small cluster of malignant cells at the invasive front of a tumor. Despite being an adverse prognosis marker, little research has been conducted on the tumor immune microenvironment of tumor buddings, especially in cervical cancer. Therefore, RNA sequencing was performed using 21 formalin-fixed, paraffin-embedded slides of cervical tissues, and differentially expressed genes (DEGs) were analyzed. Immune Pathway and Gene Database (IMPAGT) was generated for immune profiling. "Pathway in Cancer" was identified as the most enriched pathway for both up- and downregulated DEGs. Kyoto Encyclopedia of Genes and Genomes Mapper and Gene Ontology further revealed the activation of the PI3K/Akt signaling pathway. An IMPAGT analysis revealed immune dysregulation even at the tumor budding stage, especially in the PI3K/Akt/mTOR axis, with a high efficiency and integrity. These findings emphasized the clinical significance of tumor buddings and the necessity of blocking the overactivation of the PI3K/Akt/mTOR pathway to improve targeted therapy in cervical cancer.

Interleukin-8 Regulates the Autophagy and Apoptosis in Gastric Cancer Cells via Regulating PI3K/Akt Signaling Pathway

Objective. To explore the role and mechanism of interleukin-8-mediated autophagy regulation of gastric cancer (GC) cells in GC. Methods. After cell culture, the SGC7901 cell line was separated into the control group and IL-8 (20 ng/mL) group, IL-8 (40 ng/mL) group, and IL-8 (60 ng/mL) group, to verify the effects of the PI3K/Akt signal path on the modulation of autophagy in GC cells. Western blot detected autophagy markers, ATG12-ATG5 complexes, autophagy-associated pathways, and apoptosis-associated factors in GC cells. Transwell was utilized to identify invasion capability. Results. Compared with the control group, the expression of LC3II, Atg5, ATG7, Beclin1, Bax, C-cas3, C-cas9, P-PI3K, P-Akt, and ATG12-ATG5 was remarkably elevated in the IL-8 (60 ng/mL) group, IL-8 (20 ng/mL) group, and the IL-8 (40 ng/mL) group. The expression of P62 and Bcl-2 in the IL-8 (60 ng/mL) group was also lower than that of the IL-8 (20 ng/mL) group and IL-8 (40 ng/mL) group, in contrast to the controls. The invasive quantity of GC SGC7901 cells in the IL-8 (60 ng/mL) group was also remarkably higher in contrast to the IL-8 (20 ng/mL) and IL-8 (40 ng/mL) groups. The relative expressions of LC3II, Atg5, ATG7, Beclin1, Bax, C-cas3, C-cas9, P-PI3K, P-Akt, and ATG12-ATG5 complex proteins in LY294002 group were considerably elevated. LC3II, Atg5, ATG7, Beclin1, Bax, C-cas3, C-cas9, P-PI3K, P-Akt, and ATG12-ATG5 were decreased in the IL-8 + LY294002 group. The relative expressions of P62 and Bcl-2 proteins in the IL-8 + LY294002 group were remarkably elevated, and the invasion of SGC7901 cells in the IL-8 group was elevated. In contrast to the IL-8 group, the invasion quantity of gastric cancer SGC7901 cells in the IL-8 + LY294002 group was considerably decreased. Conclusion. IL-8 promotes autophagy and aggression and suppresses apoptosis of GC SGC7901 cells by regulating PI3K/AKT pathway phosphorylation.

Post-Translational Modifications in Atopic Dermatitis: Current Research and Clinical Relevance

Atopic dermatitis (AD) is a chronic and relapsing cutaneous disorder characterized by compromised immune system, excessive inflammation, and skin barrier disruption. Post-translational modifications (PTMs) are covalent and enzymatic modifications of proteins after their translation, which have been reported to play roles in inflammatory and allergic diseases. However, less attention has been paid to the effect of PTMs on AD. This review summarized the knowledge of six major classes (including phosphorylation, acetylation, ubiquitination, SUMOylation, glycosylation, o-glycosylation, and glycation) of PTMs in AD pathogenesis and discussed the opportunities for disease management.

Role of autophagy in gastric carcinogenesis

Gastric cancer represents a common and highly fatal malignancy, and thus a pathophysiology-based reconsideration is necessary, given the absence of efficient therapeutic regimens. In this regard, emerging data reveal a significant role of autophagy in gastric oncogenesis, progression, metastasis and chemoresistance. Although autophagy comprises a normal primordial process, ensuring cellular homeostasis under energy depletion and stress conditions, alterations at any stage of the complex regulatory system could stimulate a tumorigenic and promoting cascade. Among others, Helicobacter pylori infection induces a variety of signaling molecules modifying autophagy, during acute infection or after chronic autophagy degeneration. Subsequently, defective autophagy allows malignant transformation and upon cancer establishment, an overactive autophagy is stimulated. This overexpressed autophagy provides energy supplies and resistance mechanisms to gastric cancer cells against hosts defenses and anticancer treatment. This review interprets the implicated autophagic pathways in normal cells and in gastric cancer to illuminate the potential preventive, therapeutic and prognostic benefits of understanding and intervening autophagy.

Pulmonary Delivery of Docetaxel and Celecoxib by PLGA Porous Microparticles for Their Synergistic Effects Against Lung Cancer

BACKGROUND

using a combination of chemotherapeutic agents with novel drug delivery platforms to enhance the anticancer efficacy of the drug and minimizing the side effects, is very imperative for lung cancer treatments.

OBJECTIVE

The aim of the present study was to develop, characterize, and optimize porous poly (D, L-lactic-co-glycolic acid) (PLGA) microparticles for simultaneous delivery of docetaxel (DTX) and celecoxib (CXB) through the pulmonary route for lung cancer.

METHODS

Drug-loaded porous microparticles were prepared by an emulsion solvent evaporation method. The impact of various processing and formulation variables including PLGA amount, dichloromethane volume, homogenization speed, polyvinyl alcohol volume and concentration were assessed on entrapment efficiency, mean release time, particle size, mass median aerodynamic diameter, fine particle fraction and geometric standard deviation using a two-level factorial design. An optimized formulation was prepared and evaluated in terms of size and morphology using a scanning electron microscope.

RESULTS

FTIR, DSC, and XRD analysis confirmed drug entrapment and revealed no drug-polymer chemical interaction. Cytotoxicity of DTX along with CXB against A549 cells was significantly enhanced compared to DTX and CXB alone and the combination of DTX and CXB showed the greatest synergistic effect at a 1/500 ratio.

CONCLUSION

In conclusion, the results of the present study suggest that encapsulation of DTX and CXB in porous PLGA microspheres with desirable features are feasible and their pulmonary co-administration would be a promising strategy for the effective and less toxic treatment of various lung cancers.

Celecoxib repurposing in cancer therapy: molecular mechanisms and nanomedicine-based delivery technologies

While cancer remains a significant global health problem, advances in cancer biology, deep understanding of its underlaying mechanism and identification of specific molecular targets allowed the development of new therapeutic options. Drug repurposing poses several advantages as reduced cost and better safety compared with new compounds development. COX-2 inhibitors are one of the most promising drug classes for repurposing in cancer therapy. In this review, we provide an overview of the detailed mechanism and rationale of COX-2 inhibitors as anticancer agents and we highlight the most promising research efforts on nanotechnological approaches to enhance COX-2 inhibitors delivery with special focus on celecoxib as the most widely studied agent for chemoprevention or combined with chemotherapeutic and herbal drugs for combating various cancers.

Novel Applications of NSAIDs: Insight and Future Perspectives in Cardiovascular, Neurodegenerative, Diabetes and Cancer Disease Therapy

Once it became clear that inflammation takes place in the modulation of different degenerative disease including neurodegenerative, cardiovascular, diabetes and cancer the researchers has started intensive programs evaluating potential role of non-steroidal anti-inflammatory drugs (NSAIDs) in the prevention or therapy of these diseases. This review discusses the novel mechanism of action of NSAIDs and its potential use in the pharmacotherapy of neurodegenerative, cardiovascular, diabetes and cancer diseases. Many different molecular and cellular factors which are not yet fully understood play an important role in the pathogenesis of inflammation, axonal damage, demyelination, atherosclerosis, carcinogenesis thus further NSAID studies for a new potential indications based on precise pharmacotherapy model are warranted since NSAIDs are a heterogeneous group of medicines with relative different pharmacokinetics and pharmacodynamics profiles. Hopefully the new data from studies will fill in the gap between experimental and clinical results and translate our knowledge into successful disease therapy.

Celecoxib as a Valuable Adjuvant in Cutaneous Melanoma Treated with Trametinib

BACKGROUND

Melanoma patients stop responding to targeted therapies mainly due to mitogen activated protein kinase (MAPK) pathway re-activation, phosphoinositide 3 kinase/the mechanistic target of rapamycin (PI3K/mTOR) pathway activation or stromal cell influence. The future of melanoma treatment lies in combinational approaches. To address this, our in vitro study evaluated if lower concentrations of Celecoxib (IC50 in nM range) could still preserve the chemopreventive effect on melanoma cells treated with trametinib.

MATERIALS AND METHODS

All experiments were conducted on SK-MEL-28 human melanoma cells and BJ human fibroblasts, used as co-culture. Co-culture cells were subjected to a celecoxib and trametinib drug combination for 72 h. We focused on the evaluation of cell death mechanisms, melanogenesis, angiogenesis, inflammation and resistance pathways.

RESULTS

Low-dose celecoxib significantly enhanced the melanoma response to trametinib. The therapeutic combination reduced nuclear transcription factor (NF)-kB (p < 0.0001) and caspase-8/caspase-3 activation (p < 0.0001), inhibited microphthalmia transcription factor (MITF) and tyrosinase (p < 0.05) expression and strongly down-regulated the phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT) signaling pathway more significantly than the control or trametinib group (p < 0.0001).

CONCLUSION

Low concentrations of celecoxib (IC50 in nM range) sufficed to exert antineoplastic capabilities and enhanced the therapeutic response of metastatic melanoma treated with trametinib.

LACTB and LC3 could serve as potential biomarkers of gastric cancer to neoadjuvant chemotherapy with oxaliplatin plus S-1

The present study investigated and evaluated the correlation between the expression of LACTB and LC3 and the clinical outcomes of patients with advanced gastric cancer treated with oxaliplatin plus S-1 neoadjuvant chemotherapy (NACT). A total of 51 patients with advanced gastric cancer underwent NACT treatment between June 2015 and June 2017. Pathomorphological changes in gastric cancer were analyzed by H&E staining. The expression level and subcellular localization of LACTB and LC3 in paraffin-embedded biopsies were detected by immunohistochemistry and immunofluorescence. The mRNA and protein expression of LACTB were investigated by reverse transcription quantitative polymerase chain reaction and Western blotting, respectively. Statistical analysis was performed to determine the association between the expression of LACTB and LC3 and clinical chemotherapy efficacy of NACT for gastric cancer. Among the 51 patients, 3 (5.88%), 27 (52.94%), 13 (25.49%) and 8 (15.69%) displayed complete remission, partial remission, stable disease and progressive disease, respectively. The rate of decreased LACTB expression was 68.6%, while the rate of increased LC3 expression was 60.8%. Furthermore, there was a significant negative correlation between the expression of LACTB and that of LC3 following NACT (P<0.001). High expression of LC3 (P<0.01) and low expression of LACTB (P<0.01) were associated with a poor response of patients with advanced gastric cancer to NACT. In conclusion, the expression of LACTB and LC3 may serve as a promising novel biomarker for determining the prognosis of patients with advanced gastric cancer receiving NACT, while its potential clinical significance requires further elucidation.

H2S exposure-induced oxidative stress promotes LPS-mediated hepatocyte autophagy through the PI3K/AKT/TOR pathway

Hydrogen sulfide (H₂S), a common air pollutant and toxic gas, is detrimental to organisms and the environment. Exposure to highly concentrated H₂S can induce oxidative stress and autophagy. However, the mechanism underlying the liver damage caused by H₂S has not been identified. Lipopolysaccharide (LPS), the key component of endotoxin, can induce oxidative stress and autophagy. For this experiment, we used one-day-old chickens as model organisms to evaluate the effects of H₂S combined with LPS on oxidative stress and autophagy. The four groups (control group, LPS group, H₂S group and H₂S-LPS group) were observed by electron microscopy, detected by oxidative stress kit, analyzed by quantitative real-time quantitative PCR, and analyzed by Western blot. We found that the activities of antioxidant enzymes (superoxide dismutase, antioxidant glutathione, catalase, and glutathione peroxidase) decreased in the H₂S group compared to those in the control group; however, malondialdehyde levels in the H₂S group increased. Molecular-level studies showed that the expression of genes associated with the PI3K/ AKT/ TOR pathways in the H₂S group decreased, whereas the expression of other autophagy-related genes (Beclin1, ATG5 and the ratio of LC3-II/ LC3-I) increased compared to that in the control group. These findings suggest that H₂S caused oxidative stress and induced autophagy through the PI3K/ AKT/ TOR pathway in chicken liver cells. Additionally, exposure to H₂S aggravated LPS-induced oxidative stress and autophagy injury. Capsule: Aerial exposure to H₂S can cause oxidative stress in chicken livers and induce autophagy through the PI3K/AKT/TOR pathway, and can aggravate LPS-induced oxidative stress and autophagy.

C21 Fraction Refined from Marsdenia tenacissima-Induced Apoptosis is Enhanced by Suppression of Autophagy in Human Gastric Cell Lines

C21 steroidal glycosides have been extensively reported for treating several types of cancer and are widely found in Marsdenia tenacissima. In this study, a C21 fraction was synthesized from M. tenacissima, and its anti-cancer potency was assessed against in vitro gastric cell lines BGC-823, SGC-7901, and AGS. Significant growth inhibition and cell cycle arrest were observed in C21 fraction-treated gastric cancer cells. The results of apoptotic staining techniques in C21 fraction-treated gastric cells were confirmed with excess reactive oxygen species generation. Moreover, SOD and H₂O₂ levels were increased by C21 fraction, especially when combined with chloroquine (CQ). The apoptotic inducing potential of C21 fraction was also evidenced by upregulation of proapoptotic proteins cleaved-PARP and BAX and downregulation of antiapoptotic proteins Bcl-2 and p-AKT by western blot, especially in the presence of the autophagy inhibitor CQ. The results showed that the apoptosis of gastric cancer cells caused by C21 fraction was enhanced by inhibiting autophagy. The current findings reveal a new mechanism for the antitumor activity of C21 fraction on gastric cancer.

Celecoxib upregulates ULBP-1 expression in lung cancer cells via the JNK/PI3K signaling pathway and increases susceptibility to natural killer cell cytotoxicity

Lung cancer has the highest cancer mortality rate in the world, and effective therapies are still required. Cyclooxygenase-2 (COX-2) is highly expressed in numerous types of cancer, and is therefore considered a possible target of cancer treatment. Celecoxib, a selective COX-2 inhibitor, has binding pockets that interact with COX-2 and disrupt its enzymatic activities. In addition, celecoxib is able to affect cellular functions in a COX-2-independent manner. The present study aimed to investigate if celecoxib affected natural killer (NK) cell receptors and susceptibility to NK cell toxicity. For this purpose, PCR, immunoblotting, flow cytometry analysis and NK cell cytotoxicity assays were performed. The present study revealed that sublethal concentrations of celecoxib increased the expression levels of UL16-binding protein 1 (ULBP-1), a natural-killer group 2 member D (NKG2D) ligand, in lung cancer A549 and H460 cell lines. ULBP-1 mRNA and protein expression was induced in a dose- and time-dependent manner after celecoxib treatment. Expression levels of other NKG2D ligands, such as ULBP-2, ULBP-3, MHC class I-related chain A (MICA) and MICB did not change considerably compared to ULBP-1 in response to celecoxib treatment. Fluorescence microscopic images revealed abundant ULBP-1 in the cytoplasm after celecoxib treatment. Both JNK and PI3K may be involved in the induction of ULBP-1 expression after celecoxib treatment in A549 and H460 cells. In a NK cytotoxicity assay, celecoxib increased the sensitivity to NK cell-mediated cytotoxicity via interaction with ULBP-1 in lung cancer cells. Overall, the present results demonstrated that celecoxib treatment induced ULBP-1 expression in lung cancer cells, thereby increasing their susceptibility to NK cell cytotoxicity. These results suggest that the effects of conventional anticancer therapy may potentially be enhanced by using celecoxib, which targets COX-2, to enhance the sensitivity of lung cancer cells to NK cell-mediated cytotoxicity.

Celecoxib in Cancer Therapy and Prevention - Review

BACKGROUND AND OBJECTIVES

It is generally accepted that inflammatory cells found in the tumor microenvironment are involved in the neoplastic process, promoting cell proliferation, survival, and migration. Therefore, administering anti-inflammatory medication in cancer therapy seems to be justified. A potential pathway associated with the aforementioned issue is cyclooxygenase-2 inhibition, particularly as the overexpression of this enzyme has been proven to occur in cancer tissues and is also associated with a poor prognosis in several types of human malignancies. Celecoxib, a COX-2 selective inhibitor, has been utilized for over 20 years, particularly as an anti-inflammatory, analgesic and antipyretic medication. However, to date, its antineoplastic properties have not been sufficiently investigated. In recent years, the number of research studies on the antineoplastic effects of celecoxib has increased considerably. The vast majority of publications refers to preclinical studies attempting to elucidate its mechanisms of action. Clinical trials concerning celecoxib have focused primarily on the treatment of cancers of the colon, breast, lung, prostate, stomach, head and neck, as well as premalignant lesions such as familial adenoma polyposis. In this review article authors attempt to summarise the latest research which has elucidated celecoxib use in the treatment and prevention of cancer.

CONCLUSION

Both preclinical and clinical studies have demonstrated promising results of the role of celecoxib in the treatment and prevention of cancer - the best outcome was observed in colon, breast, prostate and head and neck cancers. However, more clinical trials providing real evidence-based clinical advances of celecoxib use are needed.

The Personalisation of Glioblastoma Treatment Using Whole Exome Sequencing: A Pilot Study

The molecular heterogeneity of glioblastoma has been linked to differences in survival and treatment response, while the development of personalised treatments may be a novel way of combatting this disease. Here we show for the first time that low passage number cells derived from primary tumours are greater than an 86% match genetically to the tumour tissue. We used these cells to identify eight genes that could be used for the personalisation of glioblastoma treatment and discovered a number of personalised drug combinations that were significantly more effective at killing glioblastoma cells and reducing recurrence than the individual drugs as well as the control and non-personalised combinations. This pilot study demonstrates for the first time that whole exome sequencing has the potential be used to improve the treatment of glioblastoma patients by personalising treatment. This novel approach could potentially offer a new avenue for treatment for this terrible disease.

Alantolactone enhances gemcitabine sensitivity of lung cancer cells through the reactive oxygen species-mediated endoplasmic reticulum stress and Akt/GSK3β pathway

Lung cancer is one of the leading causes of cancer‑associated mortality in China and globally. Gemcitabine (GEM), as a first‑line therapeutic drug, has been used to treat lung cancer, but GEM resistance poses a major limitation on the efficacy of GEM chemotherapy. Alantolactone (ALT), a sesquiterpene lactone compound isolated from Inula helenium, has been identified to exert anticancer activity in various types of cancer, including breast, pancreatic, lung squamous and colorectal cancer. However, the underlying mechanisms of the anticancer activity of ALT in lung cancer remain to be fully elucidated. The present study aimed to determine whether ALT enhances the anticancer efficacy of GEM in lung cancer cells and investigated the underlying mechanisms. The cell viability was assessed with a Cell Counting Kit‑8 assay. The cell cycle, apoptosis and the level of reactive oxygen species (ROS) were assessed by flow cytometry, and the expression of cell cycle‑associated and apoptosis‑associated proteins were determined by western blot analysis. The results demonstrated that ALT inhibited cell growth and induced S‑phase arrest and cell apoptosis in A549 and NCI‑H520 cells. Furthermore, ALT increased the level of ROS, inhibited the Akt/glycogen synthase kinase (GSK)3β pathway and induced endoplasmic reticulum (ER) stress in A549 and NCI‑H520 cells. Additionally, ALT treatment sensitized lung cancer cells to GEM. Analysis of the molecular mechanisms further revealed that ALT enhanced the anticancer effects of GEM via ROS‑mediated activation of the Akt/GSK3β and ER stress pathways. In conclusion, combined treatment with ALT and GEM may have potential as a clinical strategy for lung cancer treatment.

Swimming prevents nonalcoholic fatty liver disease by reducing migration inhibitory factor through Akt suppression and autophagy activation

Physical inactivity is an important contributor to obesity and fat accumulation in tissues. Critical complications of obesity include type II diabetes and nonalcoholic fatty liver disease (NAFLD). Exercise has been reported to exert ameliorating effects on obesity and NAFLD. However, the underlying mechanism is not fully understood. We showed the increase of microRNA-451 (miR-451) and decrease of macrophage migration inhibitory factor (MIF) in liver, after swim training in high fat diet (HFD) mice. MIF expression was regulated by miR-451. HFD intake caused the increase of body weights in WT and MIF knockout (KO) mice. In addition, HFD-induced liver anomalies were associated with Akt activation and autophagy suppression, which were reversed by MIF KO. In hepatocytes from HFD WT and MIF KO mice, autophagy was inhibited by exogenous rmMIF through Akt activation. Meanwhile, miR-451 antagonized the regulation of MIF on Akt signaling and autophagy. Taken together, these results indicate that MIF was decreased in liver of HFD mice due to physical exercise, and might prevent hepatic steatosis by suppressing Akt signaling and promoting autophagy.

A comprehensive evaluation of clinical efficacy and safety of celecoxib in combination with chemotherapy in metastatic or postoperative recurrent gastric cancer patients: A preliminary, three-center, clinical trial study

AIM

To evaluate the efficacy and safety of celecoxib combined with chemotherapy in the treatment of metastatic or postoperative recurrent gastric cancer.

METHODS

This preliminary, three-center, clinical trial study was conducted between September 2010 and December 2016. In the experimental group (n = 100), patients were treated with celecoxib combined with chemotherapy, and chemotherapy alone was used in the control group. Progression-free survival (PFS) was considered as the primary efficacy parameter. Overall survival (OS), remission rate (RR), quality of life (QOL) and drug safety were considered as the secondary efficacy parameters.

RESULTS

The PFS of the experimental group was 6 months, which was not significantly longer than that of the control group (5 months, P = .73). The average OS was not significantly different between the experimental group (12 months) and the control group (10 months, P = .59). The average OS of the COX-2 positive patients in the experimental group was 14 months and it was significantly longer than the 10-month OS in the control group (P = .01). The PFS of the COX-2 positive patients in the experimental group was 7.5 months, significantly longer than the 5-month PFS of patients in the control group (P < .001). No statistical significance was identified in the incidence of nausea, neutropenia, anorexia, peripheral neurotoxicity, diarrhea, vomiting, asthenia and thrombocytopenia. The EORTC QLQ-C30 questionnaire revealed that the overall QOL of the experimental group was significantly higher than that of the control group (P < .05). No statistical significance was found in the scores of functioning scale between the 2 groups. However, the scores of the symptom scale, especially for pain and fatigue in the experimental group was remarkably higher than that in the control group (P < .05). The overall score of EORTC QLQ-STO22 for the experimental group was considerably higher compared to that for the control group (P < .05). No statistical significance was identified in term of the domains of restrictions on feeding, dysphagia, anxiety, reflux, sense of taste, dry mouth, hair loss and body shape between the 2 groups (P > .05 for all mentioned outcomes).

CONCLUSION

Celecoxib combined with chemotherapy offers more clinical benefits for COX-2 positive advanced gastric cancer patients.

Flaccidoxide-13-Acetate-Induced Apoptosis in Human Bladder Cancer Cells is through Activation of p38/JNK, Mitochondrial Dysfunction, and Endoplasmic Reticulum Stress Regulated Pathway

Flaccidoxide-13-acetate, an active compound isolated from cultured-type soft coral Sinularia gibberosa, has been shown to have inhibitory effects against invasion and cell migration of RT4 and T24 human bladder cancer cells. In our study, we used an 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT), colony formation assay, and flow cytometry to determine the mechanisms of the anti-tumor effect of flaccidoxide-13-acetate. The MTT and colony formation assays showed that the cytotoxic effect of flaccidoxide-13-acetate on T24 and RT4 cells was dose-dependent, and the number of colonies formed in the culture was reduced with increasing flaccidoxide-13-acetate concentration. Flow cytometry analysis revealed that flaccidoxide-13-acetate induced late apoptotic events in both cell lines. Additionally, we found that flaccidoxide-13-acetate treatment upregulated the expressions of cleaved caspase 3, cleaved caspase 9, Bax, and Bad, and down-regulated the expressions of Bcl-2, p-Bad, Bcl-x1, and Mcl-1. The results indicated that apoptotic events were mediated by mitochondrial dysfunction via the caspase-dependent pathway. Flaccidoxide-13-acetate also provoked endoplasmic reticulum (ER) stress and led to activation of the PERK-eIF2α-ATF6-CHOP pathway. Moreover, we examined the PI3K/AKT signal pathway, and found that the expressions of phosphorylated PI3K (p-PI3K) and AKT (p-AKT) were decreased with flaccidoxide-13-acetate concentrations. On the other hand, our results showed that the phosphorylated JNK and p38 were obviously activated. The results support the idea that flaccidoxide-13-acetate-induced apoptosis is mediated by mitochondrial dysfunction, ER stress, and activation of both the p38 and JNK pathways, and also relies on inhibition of PI3K/AKT signaling. These findings imply that flaccidoxide-13-acetate has potential in the development of chemotherapeutic agents for human bladder cancer.

Akt/mTOR and AMPK signaling pathways are responsible for liver X receptor agonist GW3965-enhanced gefitinib sensitivity in non-small cell lung cancer cell lines

BACKGROUND

This study was to systemically analyze the mechanism of LXR ligand GW3965-induced sensitivity to EGFR-TKI in EGFR-TKI-resistant non-small cell lung cancer (NSCLC) cell lines.

METHODS

Gefitinib-resistant PC9 cell line (EGFR exon 19 deletion) was treated with single and combined treatment with GW3965 and gefitinib. Cell viability, apoptosis and autophagy were detected using MTT, flow cytometric analysis and immunofluorescent analysis, respectively. Autophagy-related signaling pathways were detected using Western blot analysis.

RESULTS

Inhibited cell viability by single and combined treatment with gefitinib and GW3965 were observed. Combined treatment with gefitinib and GW3965 increased LC3 II/I ratio and Beclin 1 expression. Synergistic effect of gefitinib and GW3965 on apoptosis and autophagosome accumulation as well as on the inhibition of Akt/mTOR signaling and activation of AMP-activated protein kinase (AMPK) was observed in gefitinib-resistant PC9 cells. AMPK expression showed similar profile with apoptosis and autophagy of PC9 cells.

CONCLUSIONS

We confirmed that GW3965 and gefitinib showed synergistic effect on Akt/mTOR inhibition, apoptosis and autophagy of lung cancer cells. Gefitinib sensitivity in PC9 cell line might be mediated by Akt/mTOR, AMPK and JNK signaling pathways.

Mir-215-5p induces autophagy by targeting PI3K and activating ROS-mediated MAPK pathways in cardiomyocytes of chicken

Our previous study revealed that selenium (Se) deficiency can cause myocardial injury through triggering autophagy. MicroRNAs (miRNAs) play crucial roles in autophagic cell death. However, the relationship between miRNAs and myocardial autophagy injury caused by Se deficiency remains unclear. We selected differential microRNA-215-5p (miR-215-5p) in Se-deficient myocardial tissue using high-throughput miRNA-sequencing. To further explore the role of miR-215-5p in myocardial injury, overexpression/knockdown of miR-215-5p in primary cardiomyocyte model was established by miRNAs interference technology. In this study, we report that miR-215-5p can promote myocardial autophagy by directly binding to the 3'untranslated region (3'UTR) of phosphatidylinositol-4, 5-bisphosphate 3-kinase (PI3K). Its target gene PI3K was confirmed by dual luciferase reporter assay, quantitative real-time polymerase chain reaction (qRT-PCR) and western blot in cardiomyocytes. Our results showed that overexpression of miR-215-5p could trigger myocardial autophagy through PI3K-threonine-protein kinase (AKT)-target of rapamycin (TOR) pathway. Further studies revealed that autophagic cell death was dependent on the activation of extracellular signal-regulated kinase1/2 (ERK1/2), c-Jun N-terminal kinase (JNK), p38 kinase (p38) and generation of reactive oxygen species (ROS) in overexpression of miR-215-5p in cardiomyocytes. On the contrary, miR-215-5p inhibitor can enhance cell survival capacity against autophagy by inhibiting ROS-mitogen-activated protein kinase (MAPK) pathways and activating the PI3K/AKT/TOR pathway in cardiomyocytes. Together, our findings support that miR-215-5p may modulate cell survival programs by regulating autophagy, and miR-215-5p acts as an autophagic regulator in the regulatory feedback loop that regulates cardiomyocyte survival by modulating the PI3K/AKT/TOR pathway and ROS-dependent MAPK pathways.

URI knockdown induces autophagic flux in gastric cancer cells

URI, a member of the prefoldin family of molecular chaperones, functions in the regulation of nutrient-sensitive, mTOR-dependent transcription signaling pathways. Previous studies of several tumor types demonstrated that URI exhibits characteristics similar to those of an oncoprotein. URI has been shown as a mitochondrial substrate of S6 kinase 1 (S6K1), which acts to integrate nutrient and growth factor signals to promote cell growth and survival. Notably, the Akt/mTOR/p70S6K signaling pathway constitutes major negative regulatory mechanism of autophagy. However, the role of URI in autophagy has not been explored. Here, we investigated the involvement of URI in autophagy by manipulating its expression in MGC-803 and HGC-27 cells using siRNA and transfection approaches. GFP-LC3 punctum aggregation was assessed by confocal microscopy, whereas formation of autophagic vesicles was assessed using transmission electron microscopy. NH₄Cl was used to inhibit autophagosome-lysosome fusion and to monitor autophagic flux. Expression of LC3-I, LC3-II, beclin1, total and phosphorylated mTOR, and p70S6k was assessed by Western blotting. The results showed that knockdown of URI induced significant autophagic flux in gastric cancer cells. URI regulates the expression of beclin1, which is essential for initiation of conventional autophagy. Levels of p-mTOR (Ser2448) and p-p70S6K (Thr389) increased in URI-overexpressing cells treated with the mTOR inhibitor rapamycin but decreased in URI-silenced cells. The inhibitory effect of URI silencing on mTOR and p70S6K phosphorylation was antagonized by the autophagy inhibitor 3-methyladenine. These results suggest that URI knockdown-induced autophagy is associated with the mTOR/p70S6K signaling pathway, indicating the potential existence of a novel autophagy regulatory mechanism mediated by URI.

The potential to treat lung cancer via inhalation of repurposed drugs

Lung cancer is a highly invasive and prevalent disease with ineffective first-line treatment and remains the leading cause of cancer death in men and women. Despite the improvements in diagnosis and therapy, the prognosis and outcome of lung cancer patients is still poor. This could be associated with the lack of effective first-line oncology drugs, formation of resistant tumors and non-optimal administration route. Therefore, the repurposing of existing drugs currently used for different indications and the introduction of a different method of drug administration could be investigated as an alternative to improve lung cancer therapy. This review describes the rationale and development of repositioning of drugs for lung cancer treatment with emphasis on inhalation. The review includes the current progress of repurposing non-cancer drugs, as well as current chemotherapeutics for lung malignancies via inhalation. Several potential non-cancer drugs such as statins, itraconazole and clarithromycin, that have demonstrated preclinical anti-cancer activity, are also presented. Furthermore, the potential challenges and limitations that might hamper the clinical translation of repurposed oncology drugs are described.

Erzhi Pill® Protected Experimental Liver Injury Against Apoptosis via the PI3K/Akt/Raptor/Rictor Pathway

Erzhi Pill (EZP) is one of the basic prescriptions for treating liver diseases in traditional Chinese medicine. However, its mechanism of action is still undefined. The PI3K/AKT/Raptor/Rictor signaling pathway is closely related to apoptosis and plays a significant role in the pathogenesis of liver disease. To define the mechanism of the hepatoprotective effect of EZP in the treatment of liver disease, hepatic injury induced by 2-acetylaminofluorene/partial hepatectomy was treated by EZP for 14 days. The therapeutic effect of EZP was confirmed by the decreased production of aspartate aminotransferase and alanine aminotransferase, recovery of pathological liver injury, followed by inhibition of pro-inflammatory cytokines and transforming growth factor-β1. Bromodeoxyuridine assay and TUNEL staining indicated that apoptosis was suppressed and the numbers of cells in S phase and G0/G1phase were decreased. The crucial proteins in the PI3K/AKT/Raptor/Rictor signaling pathway were deactivated in rats with experimental liver injury treated by EZP. These results indicated that the hepatoprotective effect of EZP via inhibition of hepatocyte apoptosis was closely related to repression of the PI3K/Akt/Raptor/Rictor signaling pathway.

Three-microRNA signature identified by bioinformatics analysis predicts prognosis of gastric cancer patients

AIM

To identify multiple microRNAs (miRNAs) for predicting the prognosis of gastric cancer (GC) patients by bioinformatics analysis.

METHODS

The original microarray dataset GSE93415, which included 20 GC and 20 tumor adjacent normal gastric mucosal tissues, was downloaded from the Gene Expression Omnibus database and used for screening differentially expressed miRNAs (DEMs). The cut-off criteria were P < 0.05 and fold change > 2.0. In addition, we acquired the miRNA expression profiles and clinical information of 361 GC patients from The Cancer Genome Atlas database to assess the prognostic role of the DEMs. The target genes of miRNAs were predicted using TargetScan, miRDB, miRWalk, and DIANA, and then the common target genes were selected for functional enrichment analysis.

RESULTS

A total of 110 DEMs including 19 up-regulated and 91 down-regulated miRNAs were identified between 20 pairs of GC and tumor adjacent normal tissues, and the Kaplan-Meier survival analysis found that a three-miRNA signature (miR-145-3p, miR-125b-5p, and miR-99a-5p) had an obvious correlation with the survival of GC patients. Furthermore, univariate and multivariate Cox regression analyses indicated that the three-miRNA signature could be a significant prognostic marker in GC patients. The common target genes of the three miRNAs are added up to 108 and used for Gene Functional Enrichment analysis. Biological Process and Molecular Function analyses showed that the target genes are involved in cell recognition, gene silencing and nucleic acid binding, transcription factor activity, and transmembrane receptor activity. Cellular Component analysis revealed that the genes are portion of nucleus, chromatin silencing complex, and TORC1/2 complex. Biological Pathway analysis indicated that the genes participate in several cancer-related pathways, such as the focal adhesion, PI3K, and mTOR signaling pathways.

CONCLUSION

This study justified that a three-miRNA signature could play a role in predicting the survival of GC patients.

Therapeutic role of meloxicam targeting secretory clusterin-mediated invasion in hepatocellular carcinoma cells

Recurrence and metastasis are the two leading causes of poor prognosis in patients with hepatocellular carcinoma (HCC). Secreted clusterin (sCLU) is a stress-induced chaperone that is overexpressed in HCC. However, the precise molecular mechanisms of sCLU in HCC invasion and migration are largely unknown. In the present study, it was indicated that downregulation of sCLU significantly alleviated invasiveness whereas overexpression of sCLU notably enhanced the number of invasive cells via mediating the expression level of MMP-2 and E-cadherin in Bel-7402 and SMMC-7721 cells. Furthermore, as an important mediator of invasiveness, sCLU may be responsible for proliferation and invasion suppression induced by meloxicam (a selective inhibitor of cyclooxygenase-2) in HCC cells. The combination of meloxicam and CLU shRNA significantly decreased invasion in HCC cells in vitro. Furthermore, it was observed that overexpression of sCLU significantly potentiated expression of p-AKT and MMP-2. However, downregulation of sCLU by CLU shRNA alleviated the extent of p-AKT. These results suggest the targeting of sCLU may be a novel therapeutic strategy against invasion and migration in HCC.

Silencing of COL1A2, COL6A3, and THBS2 inhibits gastric cancer cell proliferation, migration, and invasion while promoting apoptosis through the PI3k-Akt signaling pathway

This study explores the effect of COL1A2, COL6A3, and THBS2 gene silencing on proliferation, migration, invasion, and apoptosis of gastric cancer cells through the PI3K-Akt signaling pathway. The gastric cancer microarray expression data (GSE19826, GSE79973, and GSE65801) was analyzed. Gastric cancer tissues and corresponding adjacent normal tissues were extracted from patients. Positive expression rate of PI3K, Akt, and p-Akt was measured with immunohistochemistry. Two cell lines, BGC-823 and SGC-7901, were transfected and cells were grouped into blank, negative control, COL1A2-shRNA, COL6A3-shRNA, and THBS2-shRNA groups. Expressions of COL1A2, COL6A3, and THBS2 in gastric cancer cells transfected with corresponding silencing sequences were evaluated by RT-qPCR and Western blot. MTT assay, Transwell, and cell scratch tests were conducted to evaluate cell proliferation, invasion, and migration capacity, respectively. Flow cytometry was used to evaluate cell cycle distribution and apoptosis. The positive expression of PI3K, Akt, and p-Akt was higher in gastric cancer tissues compared with adjacent normal tissues, and the mRNA expression of COL1A2, COL6A3, and THBS2 was increased in gastric cancer tissues. Akt, p-Akt, and PI3K expression drastically decreased in cells transfected with COL1A2, COL6A3, and THBS2 silencing sequences. Cells transfected with COL1A2, COL6A3, and THBS2 silencing sequences exhibited promoted apoptosis but inhibited proliferation, migration, and invasion. This study demonstrates that COL1A2, COL6A3, and THBS2 gene silencing inhibits gastric cancer cell proliferation, migration, and invasion while promoting apoptosis through the PI3K-Akt signaling pathway.

Autophagy: novel applications of nonsteroidal anti-inflammatory drugs for primary cancer

In eukaryotic cells, autophagy is a process associated with programmed cell death. During this process, cytoplasmic proteins and organelles are engulfed by double-membrane autophagosomes, which then fuse with lysosomes to form autolysosomes. These autolysosomes then degrade their contents to recycle the cellular components. Autophagy has been implicated in a wide variety of physiological and pathological processes that are closely related to tumorigenesis. In recent years, an increasing number of studies have indicated that nonsteroidal anti-inflammatory drugs, such as celecoxib, meloxicam, sulindac, aspirin, sildenafil, rofecoxib, and sodium salicylate, have diverse effects in cancer that are mediated by the autophagy pathway. These nonsteroidal anti-inflammatory drugs can modulate tumor autophagy through the PI3K/Akt/mTOR, MAPK/ERK1/2, P53/DRAM, AMPK/mTOR, Bip/GRP78, CHOP/ GADD153, and HGF/MET signaling pathways and inhibit lysosome function, leading to p53-dependent G1 cell-cycle arrest. In this review, we summarize the research progress in autophagy induced by nonsteroidal anti-inflammatory drugs and the molecular mechanisms of autophagy in cancer cells to provide a reference for the potential benefits of nonsteroidal anti-inflammatory drugs in cancer chemotherapy.

In-vitro and in-vivo inhibition of melanoma growth and metastasis by the drug combination of celecoxib and dacarbazine

Celecoxib has been found to be effective in cancer prevention and treatment. Its combination with other chemotherapeutic agents was reported to produce synergistic/additive effects on various cancers. Dacarbazine (DTIC) is one of the most commonly used drugs in the treatment of metastatic melanoma. This investigation aimed to determine the in-vitro and in-vivo effects of the drug combination of celecoxib and DTIC on melanoma growth and metastasis. Melanoma cells B16-F10 and SK-MEL-28, and female C57BL/6 mice were used for the study. Our in-vitro data showed that significant synergistic effects were obtained when celecoxib was used together with various concentrations of DTIC. A study with B16-F10 cells using flow cytometry analysis showed that the drug combination induced significantly more apoptosis than each drug used individually. Our in-vivo results showed that the drug combination was much more effective than each drug used alone for the inhibition of both melanoma growth and metastasis in the B16-F10+C57BL/6 mouse models. For melanoma growth, the median survival rates for phosphate-buffered saline (PBS) (control), celecoxib (30 mg/kg), DTIC-1 (10 mg/kg), DTIC-2 (positive control, 50 mg/kg), and the drug combination (DTIC 10 mg/kg+celecoxib 30 mg/kg) were 6, 6.5, 7.5, 7.5, and 9 days, respectively. For melanoma metastasis, the average number of metastatic tumors in murine lungs was 53.7±10.7, 31.8±18.6, 21.2±21.7, 7.0±9.0, and 0.8±2.0 for PBS, DTIC-1, celecoxib, the drug combination, and DTIC-2. Our results warrant further investigation of the combination as an effective treatment for melanoma patients.

Brucein D, a Naturally Occurring Tetracyclic Triterpene Quassinoid, Induces Apoptosis in Pancreatic Cancer through ROS-Associated PI3K/Akt Signaling Pathway

Brucein D (BD), a major active quassinoid in Brucea javanica, has exhibited pronounced anticancer activities. However, the biologic mechanisms have not been fully explored. In this study, BD exhibited more potent cytotoxic effect on pancreatic cancer (PanCa) cell lines, while exerted weaker cytotoxic effects on GES-1 cells (non-tumorigenic). BD was shown to elicit apoptosis through inducing both the intrinsic and extrinsic mitochondria-mediated caspase activations. Furthermore, the BD-induced apoptotic effects were dependent on the accumulated reactive oxygen species (ROS) and inactivation of PI3K/Akt signaling pathway. Pretreatment with tempol completely prevented the cellular apoptosis induced by BD, and recovered the inactivation of AKT, which suggested ROS essentially involved in BD-elicited apoptosis and down-regulation of PI3K/Akt pathway. In addition, the results obtained from orthotopic xenograft in nude mice were congruent with those of the in vitro investigations. These results support the notion that BD held good potential to be further developed into an effective pharmaceutical agent for the treatment of PanCa.

Effect of silencing colon cancer-associated transcript 2 on the proliferation, apoptosis and autophagy of gastric cancer BGC-823 cells

The role of long non-coding RNAs (lncRNAs) in the carcinogenesis and progression of tumors has been receiving increasing attention. Colon cancer-associated transcript 2 (CCAT2), a type of oncogenic lncRNA, is regarded as a novel biomarker of poor prognosis and metastasis in various types of cancer. However, the molecular contributions of CCAT2 to gastric cancer (GC) progression remain largely unclear. The aim of the present study was to demonstrate the effect of silencing CCAT2 on the biological behavior of GC BGC-823 cells and illustrate the potential underlying molecular mechanisms. A short hairpin RNA interference plasmid pRNAT-U6.1-CCAT2 targeting CCAT2 was successfully constructed. At 48 h after transfection with the interference plasmid, the survival rate of BGC-823 cells was significantly decreased, as determined by the MTT assay. In addition, RT-qPCR results revealed that CCAT2 gene expression was effectively suppressed by the transfection, while POU domain class 5 transcription factor 1B (POU5F1B) gene expression was significantly decreased. Terminal deoxynucleotidyl transferase dUTP nick end labeling assay further revealed that the apoptotic index was significantly higher in the interference group. Western blot analysis also demonstrated that the expression of beclin-1 protein was significantly increased, whereas the expression levels of phosphoinositide 3-kinase (PI3K) and mammalian target of rapamycin (mTOR) proteins were downregulated in the interference group. In conclusion, CCAT2 was able to positively regulate the expression of POU5F1B gene. Furthermore, silencing of CCAT2 gene inhibited the proliferation of BGC-823 cells, as well as induced apoptosis and autophagy in BGC-823 cells, by suppression of the PI3K/mTOR signaling pathways.

Anti-cancer effect of low dose of celecoxib may be associated with lnc-SCD-1:13 and lnc-PTMS-1:3 but not COX-2 in NCI-N87 cells

In order to investigate the mechanism of celecoxib and whether long non-coding RNAs (lncRNAs) were involved in the effects of celecoxib treatment in NCI-N87 cells, NCI-N87 cells were treated with 15, 30 and 60 µM celecoxib and an MTT assay was performed to assess cell viability. Following treatment with 15 µM celecoxib, the cell cycle and apoptosis were analyzed by flow cytometry, and the mRNA levels of lnc-SCD-1:13, lnc-PTMS-1:3, cyclooxygenase-2 (COX-2), integrin α3 (ITGA3) and DSH homolog 1 (DVL1) were detected by reverse transcription quantitative PCR (RT-qPCR) in NCI-N87 cells. MTT analysis demonstrated that celecoxib significantly inhibited cell viability in treated cells compared with untreated cells. Flow cytometry analysis revealed that, compared with untreated cells, the percentage of cells in the G0/G1 phase was significantly increased, and the percentage of cells in the S and G2 phase was decreased. In addition, the percentage of early and late apoptotic cells was increased in cells treated with 15 µM celecoxib compared with the control. RT-qPCR analysis also demonstrated that the mRNA levels of lnc-SCD-1:13, lnc-PTMS-1:3, ITGA3 and DVL1 were increased following treatment with celecoxib (15 µM; P<0.05). However, there were no significant differences in the expression of COX-2 mRNA between cells treated with celecoxib (15 µM) and untreated cells. The present study demonstrated that a low dose of celecoxib may be involved in regulating cell growth independent of COX-2 in NCI-N87 cells. Furthermore, ITGA3 and/or DVL1 co-expressed with lnc-SCD-1:13 and lnc-PTMS-1:3 may be associated with the effects of treatment with a low dose of celecoxib in NCI-N87 cells.

Human bocavirus induces apoptosis and autophagy in human bronchial epithelial cells

Human bocavirus (HBoV) is classified in the Bocavirus genus within the Parvoviridae family, first identified from children with respiratory diseases. Previous studies have investigated the stimulating effect of HBoV on cell apoptosis and autophagy. In the present study, human bronchial epithelial cells (HBECs) were utilized to examine the mechanism of HBoV recombination expressing vector (pWHL-1) on the promotion of cell apoptosis and autophagy. The results from the present study indicated that pWHL-1 inhibited the proliferation of HBECs in a time-dependent manner. Additionally, pWHL-1induced apoptosis, as substantiated by an increased apoptotic rate and presence of autophagosomes. Following pWHL-1 transfection, proliferating cell nuclear antigen, caspase-3 and B cell lymphoma 2 (Bcl-2) protein expression levels were decreased, with the exception of Bcl-2 associated × (Bax) protein, which increased. mRNA and protein expression levels of microtubule-associated protein 1A/1B-light chain 3 (LC3) II and autophagy protein 5 were increased in pWHL-1-transfected HBECs, whereas, the mRNA and protein levels of LC3I and sequestosome 1 were decreased. Notably, pWHL-1 also enhanced the activation of p53 and inhibited AKT activation in HBECs. Results from the present study suggest that pWHL-1 induces apoptosis and autophagy, thus providing a novel insight into the effect of HBoV and its uses in respiratory diseases.

A novel epidermal growth factor receptor inhibitor for treating lung cancer

To investigate the effects of a novel synthetic epidermal growth factor receptor inhibitor, COMPOUND7809, on the inhibition of lung cancer growth in vitro and the underlying mechanisms, we treated three lung tumor cell lines (A549, SK-LU-1, and NCI-H23) with COMPOUND7809 and a Food and Drug Administration-approved epidermal growth factor receptor inhibitor gefitinib. Then, we examined cell growth in a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, cell survival in a Cell Counting Kit-8 assay, and cell apoptosis by Annexin V flow cytometry in the presence of fluorouracil. We found that compared to gefitinib, COMPOUND7809 inhibited cell growth more potentially and induced more cell death in the presence of fluorouracil. Thus, our study demonstrates that COMPOUND7809 may be a promising epidermal growth factor receptor inhibitor for human lung cancer therapy.

Functional role of autophagy in gastric cancer

Autophagy is a highly regulated catabolic pathway responsible for the degradation of long-lived proteins and damaged intracellular organelles. Perturbations in autophagy are found in gastric cancer. In host gastric cells, autophagy can be induced by Helicobacter pylori (or H. pylori) infection, which is associated with the oncogenesis of gastric cancer. In gastric cancer cells, autophagy has both pro-survival and pro-death functions in determining cell fate. Besides, autophagy modulates gastric cancer metastasis by affecting a wide range of pathological events, including extracellular matrix (ECM) degradation, epithelial-to-mesenchymal transition (EMT), tumor angiogenesis, and tumor microenvironment. In addition, some of the autophagy-related proteins, such as Beclin 1, microtubule-associated protein 1 light chain 3 (MAP1-LC3), and p62/sequestosome 1 (SQSTM1) have certain prognostic values for gastric cancer. In this article, we review the recent studies regarding the functional role of autophagy in gastric cancer.

Autophagy regulation and its role in gastric cancer and colorectal cancer

BACKGROUND

Autophagy is associated with the occurrence, development, cellular adaptation, progression, treatment and prognosis of gastric cancer (GC) and colorectal cancer (CRC). The effect of autophagy in these two cancers has attracted our attention.

OBJECTIVE

The aim of this study was to describe the functional and regulatory mechanisms associated with autophagy in GC and CRC.

METHODS

We reviewed recent publications describing the role of autophagy in GC and CRC, including the functional characteristics, clinical significance and regulatory mechanisms.

RESULTS

Autophagy plays context-dependent dual roles in the development and progression of GC and CRC. It can either promote tumor growth and cell survival or can contribute to tumor suppression and promote cell death. Both of these effects employ complex regulatory networks, such as those mediated by p53, PI3K/Akt/mTOR, Ras and microRNA. Among the cellular process associated with these pathways, autophagy is a potential target for anti-tumor therapy.

CONCLUSION

Autophagy is associated with both tumorigenic and protective effects in cancer. However, the role of autophagy in GC and CRC remains unclear. Although the translation of the basic science of autophagy into clinical practice is a long process, the modulation of autophagy as a potential therapeutic approach in GC and CRC merits further investigation.

Fas expression is downregulated in gastric cancer

The aim of the present study was to investigate Fas expression in tumor samples from patients with gastric cancer, in order to determine the involvement of the Fas signaling pathway. The protein expression levels of Fas, caspase-8, caspase-3 and poly (adenosine diphosphate-ribose) polymerase 1 (PARP1) were examined in gastric cancer specimens and their associations with clinical pathological parameters were analyzed with immunohistochemical staining and western blot analysis. The mRNA expression was quantified with quantitative PCR and apoptosis was examined with a FACScan flow cytometer. The results demonstrated that the downregulation of Fas expression was correlated with less histological differentiation, gender (male), and increased lymph node and distant metastases (P<0.05). In the AGS established gastric cancer cell line, upregulation of the Fas signaling pathway promoted the apoptosis of gastric cancer cells by upregulating the expression of caspase-8 and caspase-3, and downregulating the expression of PARP1. The present study demonstrated that Fas was associated with gastric cancer and promoted the apoptosis of gastric cancer cells via caspase-8, caspase-3 and PARP1. These results suggested that caspase-8, caspase-3 and PARP1 may be triggers of gastric cancer, and upregulation of caspase-8 and caspase-3 expression, or inhibition of PARP1 expression may improve the therapeutic outcome in patients with gastric cancer.

Dihydroceramide desaturase inhibitors induce autophagy via dihydroceramide-dependent and independent mechanisms

BACKGROUND

Autophagy consists on the delivery of cytoplasmic material and organelles to lysosomes for degradation. Research on autophagy is a growing field because deciphering the basic mechanisms of autophagy is key to understanding its role in health and disease, and to paving the way to discovering novel therapeutic strategies. Studies with chemotherapeutic drugs and pharmacological tools support a role for dihydroceramides as mediators of autophagy. However, their effect on the autophagy outcome (cell survival or death) is more controversial.

METHODS

We have examined the capacity of structurally varied Des1 inhibitors to stimulate autophagy (LC3-II analysis), to increase dihydroceramides (mass spectrometry) and to reduce cell viability (SRB) in T98G and U87MG glioblastoma cells under different experimental conditions.

RESULTS

The compounds activity on autophagy induction took place concomitantly with accumulation of dihydroceramides, which occurred by both stimulation of ceramide synthesis de novo and reduction of Des1 activity. However, autophagy was also induced by the test compounds after preincubation with myriocin and in cells with a reduced capacity to produce dihydroceramides (U87DND). Autophagy inhibition with 3-methyladenine in the de novo dihydroceramide synthesis competent U87MG cells increased cytotoxicity, while genetic inhibition of autophagy in U87DND cells, poorly efficient at synthesizing dihydroceramides, augmented resistance to the test compounds.

CONCLUSION

Dihydroceramide desaturase 1 inhibitors activate autophagy via both dihydroceramide-dependent and independent pathways and the balance between the two pathways influences the final cell fate.

GENERAL SIGNIFICANCE

The cells capacity to biosynthesize dihydroceramides must be taken into account in proautophagic Des1 inhibitors-including therapies.

Co-expressed differentially expressed genes and long non-coding RNAs involved in the celecoxib treatment of gastric cancer: An RNA sequencing analysis

The aim of the present study was to investigate the mechanisms of long non-coding RNAs (lncRNAs) in a gastric cancer cell line treated with celecoxib. The human gastric carcinoma cell line NCI-N87 was treated with 15 µM celecoxib for 72 h (celecoxib group) and an equal volume of dimethylsulfoxide (control group), respectively. Libraries were constructed by NEBNext Ultra RNA Library Prep kit for Illumina. Paired-end RNA sequencing reads were aligned to a human hg19 reference genome using TopHat2. Differentially expressed genes (DEGs) and lncRNAs were identified using Cuffdiff. Enrichment analysis was performed using GO-function package and KEGG profile in Bioconductor. A protein-protein interaction network was constructed using STRING database and module analysis was performed using ClusterONE plugin of Cytoscape. ATP5G1, ATP5G3, COX8A, CYC1, NDUFS3, UQCRC1, UQCRC2 and UQCRFS1 were enriched in the oxidative phosphorylation pathway. CXCL1, CXCL3, CXCL5 and CXCL8 were enriched in the chemokine signaling and cytokine-cytokine receptor interaction pathways. ITGA3, ITGA6, ITGB4, ITGB5, ITGB6 and ITGB8 were enriched in the integrin-mediated signaling pathway. DEGs co-expressed with lnc-SCD-1:13, lnc-LRR1-1:2, lnc-PTMS-1:3, lnc-S100P-3:1, lnc-AP000974.1-1:1 and lnc-RAB3IL1-2:1 were enriched in the pathways associated with cancer, such as the basal cell carcinoma pathway in cancer. In conclusion, these DEGs and differentially expressed lncRNAs may be important in the celecoxib treatment of gastric cancer.

Disruption of the ribosomal P complex leads to stress-induced autophagy

The human ribosomal P complex, which consists of the acidic ribosomal P proteins RPLP0, RPLP1, and RPLP2 (RPLP proteins), recruits translational factors, facilitating protein synthesis. Recently, we showed that overexpression of RPLP1 immortalizes primary cells and contributes to transformation. Moreover, RPLP proteins are overexpressed in human cancer, with the highest incidence in breast carcinomas. It is thought that disruption of the P complex would directly affect protein synthesis, causing cell growth arrest and eventually apoptosis. Here, we report a distinct mechanism by which cancer cells undergo cell cycle arrest and induced autophagy when RPLP proteins are downregulated. We found that absence of RPLP0, RPLP1, or RPLP2 resulted in reactive oxygen species (ROS) accumulation and MAPK1/ERK2 signaling pathway activation. Moreover, ROS generation led to endoplasmic reticulum (ER) stress that involved the EIF2AK3/PERK-EIF2S1/eIF2α-EIF2S2-EIF2S3-ATF4/ATF-4- and ATF6/ATF-6-dependent arms of the unfolded protein response (UPR). RPLP protein-deficient cells treated with autophagy inhibitors experienced apoptotic cell death as an alternative to autophagy. Strikingly, antioxidant treatment prevented UPR activation and autophagy while restoring the proliferative capacity of these cells. Our results indicate that ROS are a critical signal generated by disruption of the P complex that causes a cellular response that follows a sequential order: first ROS, then ER stress/UPR activation, and finally autophagy. Importantly, inhibition of the first step alone is able to restore the proliferative capacity of the cells, preventing UPR activation and autophagy. Overall, our results support a role for autophagy as a survival mechanism in response to stress due to RPLP protein deficiency.

Gefitinib induces lung cancer cell autophagy and apoptosis via blockade of the PI3K/AKT/mTOR pathway

Gefitinib is a selective inhibitor of the tyrosine kinase epidermal growth factor receptor, which inhibits tumor pathogenesis, metastasis and angiogenesis, as well as promoting apoptosis. Therefore, gefitinib presents an effective drug for the targeted therapy of lung cancer. However, the underlying mechanisms by which gefitinib induces lung cancer cell death remain unclear. To investigate the effects of gefitinib on lung cancer cells and the mechanism of such, the present study analyzed the effect of gefitinib on the autophagy, apoptosis and proliferation of the A549 and A549-gefitinib-resistant (GR) cell lines GR. The regulation of the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT)/ mammalian target of rapamycin (mTOR) pathway was also investigated. Acridine orange staining revealed that gefitinib induced autophagy of A549 cells but not A549-GR cells. In addition, gefitinib promoted apoptosis and inhibited proliferation of A549 cells but not A549-GR cells. Furthermore, western blot analysis demonstrated that gefitinib treatment led to the downregulation of PI3K, AKT, pAKT, mTOR and phosphorylated-mTOR protein expression in A549 cells but not A549-GR cells. LY294002 blocked the PI3K/AKT/mTOR pathway and induced autophagy and apoptosis of A549 cells, however, no synergistic effect was observed following combined treatment with gefitinib and LY294002. In conclusion, the results of the present study indicate that gefitinib promotes autophagy and apoptosis of lung cancer cells via blockade of the PI3K/AKT/mTOR pathway, which leads to lung cancer cell death.

Meloxicam suppresses hepatocellular carcinoma cell proliferation and migration by targeting COX-2/PGE2-regulated activation of the β-catenin signaling pathway

Recurrence and metastasis are the two leading causes of poor prognosis of hepatocellular carcinoma (HCC) patients. Cyclooxygenase (COX)-2 is overexpressed in many types of cancers including HCC and promotes its metastasis. Meloxicam is a selective COX-2 inhibitor that has been reported to exert an anti-proliferation and invasion/migration response in various tumors. In this study, we examined the role of meloxicam on HCC cell proliferation and migration and explored the molecular mechanisms underlying this effect. We found that meloxicam inhibited HCC cell proliferation and had a cell cycle arrest effect in human HCC cells. Furthermore, meloxicam suppressed the ability of HCC cells expressing higher levels of COX-2 and prostaglandin E2 (PGE2) to migration via potentiating expression of E-cadherin and alleviating expression of matrix metalloproteinase (MMP)-2 and -9. COX-2/PGE2 has been considered to activate the β-catenin signaling pathway which promotes cancer cell migration. We found that treatment with PGE2 significantly enhanced nuclear accumulation of β-catenin and the activation of GSK3β which could be reversed by meloxicam in HCC cells. We also observed that HCC cell migration and upregulation of the level of MMP-2/9 and downregulation of E-cadherin induced by PGE2 were suppressed by FH535, an inhibitor of β-catenin. Taken together, these findings provide a new treatment strategy against HCC proliferation and migration.

Integrated analysis of long non-coding RNA competing interactions reveals the potential role in progression of human gastric cancer

Abnormal expression of long non-coding RNAs (lncRNAs) have been shown to play an important role in tumor biology. The Cancer Genome Atlas (TCGA) platform is a large sample sequencing database of lncRNAs, and further analysis of the associations between these data and patients' clinical related information can provide new approaches to find the functions of lncRNA. In the present study, 361 RNA sequencing profiles of gastric cancer (GC) patients were selected from TCGA. Then, we constructed the lncRNA-miRNA-mRNA competitive endogenous RNA (ceRNA) network of GC. There were 25 GC specific lncRNAs (fold change >2, p<0.05) identified, 19 of them were included in ceRNA network. Subsequently, we selected these 19 key lncRNAs and analyzed the correlations with clinical features and overall survival, 14 of them were discriminatively expressed with tumor size, tumor grade, TNM stage and lymphatic metastasis (p<0.05). In addition, eight lncRNAs (RPLP0P2, FOXD2-AS1, H19, TINCR, SLC26A4-AS1, SMIM10L2A, SMIM10L2B and SNORD116-4) were found to be significantly associated with overall survival (log-rank p<0.05). Finally, two key lncRNAs HOTAIR and UCA1 were selected for validation of their expression levels in 82 newly diagnosed GC patients by qRT-PCR. Results showed that the fold changes between TCGA and qRT-PCR were 100% in agreement. In addition, we also found that HOTAIR was significantly correlated with tumor size and lymphatic metastasis (p<0.05), and UCA1 was significantly correlated with tumor size, TNM stage and lymphatic metastasis (p<0.05). The clinical relevance of the two lncRNAs and the bioinformatics analysis results were almost the same. Overall, our study showed the GC specific lncRNAs expression patterns and a ceRNA network in GC. Clinical features related to GC specific lncRNAs also suggested these lncRNAs are worthwhile for further study as novel candidate biomarkers for the clinical diagnosis of GC and potential indicators for prognosis.

Knockdown of Rap1b Enhances Apoptosis and Autophagy in Gastric Cancer Cells via the PI3K/Akt/mTOR Pathway

Gastric cancer (GC) is the fourth most common malignancy and the second leading cause of cancer mortality around the world. However, the regulatory mechanisms of GC tumorigenesis and cancer cell motility are completely unknown. We investigated the role of a RAS-related protein (Rap1b) in the progression of GC. Our results showed that the expression of Rap1b is aberrantly upregulated in GC tissue samples and human GC cell lines, and the high expression of Rap1b indicated a positive correlation with poor prognosis in patients with GC. Inhibition of endogenous Rap1b dramatically reduced the cell cycle progression but strongly enhanced the apoptosis capacity of human GC cell lines MKN-28 and SGC-7901 cells compared with the control group. Western blotting assay showed that Rap1b inhibition resulted in a significant increase in the ratio of LC3-II to LC3-I, and the levels of p62 protein were decreased in both MKN-28 and SGC-7901 cells. Furthermore, PI3K/Akt/mTOR activation was found to be maintained in a low level in the normal gastric mucosal epithelial cells, while it was significantly upregulated in GC cells, which could be decreased by Rap1b inhibition. The PI3K inhibitor LY294002 was enhanced but activator insulin-like growth factor 1 (IGF-1) blocked the Rap1b silencing-induced enhancement of apoptosis and autophagy in MKN-28 and SGC-7901 cells. In conclusion, we demonstrate that Rap1b expression is aberrantly increased in GC, resulting in the inhibition of autophagy and apoptosis of GC cells by the PI3K/Akt/mTOR pathway. This might provide a new understanding and represent a novel therapeutic target for human GC.