Troxerutin (TXN) potentiated 5-Fluorouracil (5-Fu) treatment of human gastric cancer through suppressing STAT3/NF-κB and Bcl-2 signaling pathways

Immune perturbation network identifies an EMT subtype with chromosomal instability and tumor immune-desert microenvironment

Most gastric cancer (GC) subtypes are identified through transcriptional profiling overlooking dynamic changes and interactions in gene expression. Based on the background network of global immune genes, we constructed sample-specific edge-perturbation matrices and identified four molecular network subtypes of GC (MNG). MNG-1 displayed the best prognosis and vigorous cell cycle activity. MNG-2 was enriched by immune-hot phenotype with the potential for immunotherapy response. MNG-3 and MNG-4 were identified with epithelial-mesenchymal transition (EMT) peculiarity and worse prognosis, termed EMT subtypes. MNG-3 was characterized by low mutational burden and stromal cells and considered a replica of previous subtypes associated with poor prognosis. Notably, MNG-4 was considered a previously undefined subtype with a dismal prognosis, characterized by chromosomal instability and immune-desert microenvironment. This subtype tended to metastasize and was resistant to respond to immunotherapy. Pharmacogenomics analysis showed three therapeutic agents (NVP-BEZ235, LY2606368, and rutin) were potential interventions for MNG-4.

Evaluation of drug sensitivity, immunological characteristics, and prognosis in melanoma patients using an endoplasmic reticulum stress-associated signature based on bioinformatics and pan-cancer analysis

We aimed to develop endoplasmic reticulum (ER) stress-related risk signature to predict the prognosis of melanoma and elucidate the immune characteristics and benefit of immunotherapy in ER-related risk score-defined subgroups of melanoma based on a machine learning algorithm. Based on The Cancer Genome Atlas (TCGA) melanoma dataset (n = 471) and GTEx database (n = 813), 365 differentially expressed ER-associated genes were selected using the univariate Cox model and LASSO penalty Cox model. Ten genes impacting OS were identified to construct an ER-related signature by using the multivariate Cox regression method and validated with the Gene Expression Omnibus (GEO) dataset. Thereafter, the immune features, CNV, methylation, drug sensitivity, and the clinical benefit of anticancer immune checkpoint inhibitor (ICI) therapy in risk score subgroups, were analyzed. We further validated the gene signature using pan-cancer analysis by comparing it to other tumor types. The ER-related risk score was constructed based on the ARNTL, AGO1, TXN, SORL1, CHD7, EGFR, KIT, HLA-DRB1 KCNA2, and EDNRB genes. The high ER stress-related risk score group patients had a poorer overall survival (OS) than the low-risk score group patients, consistent with the results in the GEO cohort. The combined results suggested that a high ER stress-related risk score was associated with cell adhesion, gamma phagocytosis, cation transport, cell surface cell adhesion, KRAS signalling, CD4 T cells, M1 macrophages, naive B cells, natural killer (NK) cells, and eosinophils and less benefitted from ICI therapy. Based on the expression patterns of ER stress-related genes, we created an appropriate predictive model, which can also help distinguish the immune characteristics, CNV, methylation, and the clinical benefit of ICI therapy. KEY MESSAGES: Melanoma is the cutaneous tumor with a high degree of malignancy, the highest fatality rate, and extremely poor prognosis. Model usefulness should be considered when using models that contained more features. We constructed the Endoplasmic Reticulum stress-associated signature using TCGA and GEO database based on machine learning algorithm. ER stress-associated signature has excellent ability for predicting prognosis for melanoma.

Reanalysis of single-cell data reveals macrophage subsets associated with the immunotherapy response and prognosis of patients with endometrial cancer

Endometrial cancer (EC) is an aggressive gynecological malignancy with an increased incidence rate. The immune landscape crucially affects immunotherapy efficacy and prognosis in EC patients. Here, we characterized the distinct tumor microenvironment signatures of EC tumors by analyzing single-cell RNA sequencing data from Gene Expression Omnibus and bulk RNA sequencing data from The Cancer Genome Atlas, which were compared with normal endometrium. Three macrophage subsets were identified, and two of them showed tissue-specific distribution. One of the macrophage subsets was dominant in macrophages derived from EC and exhibited characteristic behaviors such as promoting tumor growth and metastasis. One of the other macrophage subsets was mainly found in normal endometrium and served functions related to antigen presentation. We also identified a macrophage subset that was found in both EC and normal endometrial tissue. However, the pathway and cellular cross-talk of this subset were completely different based on the respective origin, suggesting a tumor-related differentiation mechanism of macrophages. Additionally, the tumor-enriched macrophage subset was found to predict immunotherapy responses in EC. Notably, we selected six genes from macrophage subset markers that could predict the survival of EC patients, SCL8A1, TXN, ANXA5, CST3, CD74 and NANS, and constructed a prognostic signature. To verify the signature, we identified immunohistochemistry for the tumor samples of 83 EC patients based on the selected genes and further followed up with the survival of the patients. Our results provide strong evidence that the signature can effectively predict the prognosis of EC patients.

An Evaluation of Fluorouracil plus Paclitaxel and Oxiliplatin as a First-Line Treatment for Advanced Gastric Squamous Cell Carcinoma

Objective. To investigate the efficacy of fluorouracil (FU) combined with paclitaxel (PTX) and oxaliplatin (OXA) as the first-line treatment for advanced gastric signet ring cell carcinoma (SRCC) and its influence on human epidermal growth factor receptor 2 (HER-2) expression. Methods. We collected one hundred and sixty-eight patients with advanced gastric SRCC, including 87 patients treated with FU combined with PTX and OXA as the study group (SG) and 81 patients treated with FU combined with OXA as the control group (CG). We compared indicators such as efficacy and adverse reactions after treatment between the two groups and also detected serum HER-2 expression pre- and post-treatment. Results. The incidence of adverse reactions differed insignificantly between SG and CG $\left(P>0.05\right)$ . SG presented a notably higher objective response rate (ORR) and disease control rate (DCR) than that of CG $\left(P<0.05\right)$ . After treatment, the serum HER-2 expression level of patients in both groups decreased significantly $\left(P<0.05\right)$ , and that in SG was significantly declined compared to CG $\left(P<0.05\right)$ . HER-2 was negatively correlated with the efficacy of both SG and CG. The 1-year survival rate in SG (29.89%) was significantly higher than that in CG (16.05%) $\left(P<0.05\right)$ . The median OS and PFS were higher in DG than that in CG $\left(P<0.05\right)$ . Conclusion. FU combined with PTX and OXA can effectively improve the efficacy of first-line treatment for advanced gastric SRCC while reducing HER-2 expression, without increasing the adverse reaction rate. This treatment is worthy of clinical promotion.

Long noncoding RNA SNHG6 silencing sensitized esophageal cancer cells to 5-FU via EZH2/STAT pathway

Chemotherapy was the main treatment method for esophageal cancer (EC) patients. However, chemotherapy resistance due to multiple factors is a major barrier to EC treatment. For investigating how small nucleolar RNA host gene 6 (SNHG6) affected the 5-fluorouracil (5-FU) resistance in EC as well as its possible molecular mechanism. This work conducted cell viability assay, clone formation, scratch assays together with cell apoptosis for evaluating the roles of SNHG6 and enhancer of zeste homolog 2 (EZH2, the histone-lysine N-methyltransferase). Relevant molecular mechanism was identified by RT-qPCR analysis together with Western-blot (WB) assays. Our data showed that SNHG6 expression increased in EC cells. SNHG6 promotes colony formation and migration, whereas suppresses EC cell apoptosis. SNHG6 silencing markedly promoted 5-FU-mediated suppression on KYSE150 and KYSE450 cells. Additional mechanism studies showed that SNHG6 modulating STAT3 and H3K27me3 via promoting EZH2 level. Similar to the function of SNHG6, abnormal expression of EZH2 promotes the malignancy of EC and intensifies its resistance to 5-FU. In addition, overexpression of EZH2 abolished the role of SNHG6 silencing in 5-FU sensitivity in EC cells. SNHG6 overexpression promoted malignancy of EC and increased EC cell resistance to 5-FU. Besides, further molecular mechanism studies provided a novel regulatory pathways that SNHG6 knockdown promoted EC cell sensitivity to 5-FU by modulating STAT3 and H3K27me3 via promoting EZH2 expression.

Polyphenol Mechanisms against Gastric Cancer and Their Interactions with Gut Microbiota: A Review

The lack of new drugs and resistance to existing drugs are serious problems in gastric cancer(GC) treatment. The research found polyphenols possess anti-Helicobacter pylori(Hp) and antitumor activities and may be used in the research and development of drugs for cancer prevention and treatment. However, polyphenols are affected by their chemical structures and physical properties, which leads to relatively low bioavailability and bioactivity in vivo. The intestinal flora can improve the absorption, utilization, and biological activity of polyphenols, whereas polyphenol compounds can increase the richness of the intestinal flora, reduce the activity of carcinogenic bacteria, stabilize the proportion of core flora, and maintain homeostasis of the intestinal microenvironment. Our review summarizes the gastrointestinal flora-mediated mechanisms of polyphenol against GC.

Signaling Pathways Involved in 5-FU Drug Resistance in Cancer

Anti-metabolite drugs prevent the synthesis of essential cell growth compounds. 5-fluorouracil is used as an anti-metabolic drug in various cancers in the first stage of treatment. Unfortunately, in some cancers, 5-fluorouracil has low effectiveness because of its drug resistance. Studies have shown that drug resistance to 5-fluorouracil is due to the activation of specific signaling pathways and increased expressions of enzymes involved in drug metabolites. However, when 5-fluorouracil is used in combination with other drugs, the sensitivity of cancer cells to 5-fluorouracil increases, and the effect of drug resistance is reversed. This study discusses how the function of 5-fluorouracil in JAK/STAT, Wnt, Notch, NF-κB, and hedgehogs in some cancers.

Modulation of TLR/NF-κB/NLRP Signaling by Bioactive Phytocompounds: A Promising Strategy to Augment Cancer Chemotherapy and Immunotherapy

Background

Tumors often progress to a more aggressive phenotype to resist drugs. Multiple dysregulated pathways are behind this tumor behavior which is known as cancer chemoresistance. Thus, there is an emerging need to discover pivotal signaling pathways involved in the resistance to chemotherapeutic agents and cancer immunotherapy. Reports indicate the critical role of the toll-like receptor (TLR)/nuclear factor-κB (NF-κB)/Nod-like receptor pyrin domain-containing (NLRP) pathway in cancer initiation, progression, and development. Therefore, targeting TLR/NF-κB/NLRP signaling is a promising strategy to augment cancer chemotherapy and immunotherapy and to combat chemoresistance. Considering the potential of phytochemicals in the regulation of multiple dysregulated pathways during cancer initiation, promotion, and progression, such compounds could be suitable candidates against cancer chemoresistance.

Objectives

This is the first comprehensive and systematic review regarding the role of phytochemicals in the mitigation of chemoresistance by regulating the TLR/NF-κB/NLRP signaling pathway in chemotherapy and immunotherapy.

Methods

A comprehensive and systematic review was designed based on Web of Science, PubMed, Scopus, and Cochrane electronic databases. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed to include papers on TLR/NF-κB/NLRP and chemotherapy/immunotherapy/chemoresistance by phytochemicals.

Results

Phytochemicals are promising multi-targeting candidates against the TLR/NF-κB/NLRP signaling pathway and interconnected mediators. Employing phenolic compounds, alkaloids, terpenoids, and sulfur compounds could be a promising strategy for managing cancer chemoresistance through the modulation of the TLR/NF-κB/NLRP signaling pathway. Novel delivery systems of phytochemicals in cancer chemotherapy/immunotherapy are also highlighted.

Conclusion

Targeting TLR/NF-κB/NLRP signaling with bioactive phytocompounds reverses chemoresistance and improves the outcome for chemotherapy and immunotherapy in both preclinical and clinical stages.

Natural products: potential treatments for cisplatin-induced nephrotoxicity

Cisplatin is a clinically advanced and highly effective anticancer drug used in the treatment of a wide variety of malignancies, such as head and neck, lung, testis, ovary, breast cancer, etc. However, it has only a limited use in clinical practice due to its severe adverse effects, particularly nephrotoxicity; 20%–35% of patients develop acute kidney injury (AKI) after cisplatin administration. The nephrotoxic effect of cisplatin is cumulative and dose dependent and often necessitates dose reduction or withdrawal. Recurrent episodes of AKI result in impaired renal tubular function and acute renal failure, chronic kidney disease, uremia, and hypertensive nephropathy. The pathophysiology of cisplatin-induced AKI involves proximal tubular injury, apoptosis, oxidative stress, inflammation, and vascular injury in the kidneys. At present, there are no effective drugs or methods for cisplatin-induced kidney injury. Recent in vitro and in vivo studies show that numerous natural products (flavonoids, saponins, alkaloids, polysaccharide, phenylpropanoids, etc.) have specific antioxidant, anti-inflammatory, and anti-apoptotic properties that regulate the pathways associated with cisplatin-induced kidney damage. In this review we describe the molecular mechanisms of cisplatin-induced nephrotoxicity and summarize recent findings in the field of natural products that undermine these mechanisms to protect against cisplatin-induced kidney damage and provide potential strategies for AKI treatment.

METTL3‑mediated m6A modification of Bcl‑2 mRNA promotes non‑small cell lung cancer progression

Methyltransferase‑like 3 (METTL3) is an RNA methyltransferase that mediates modification of N6‑methyladenosine (m6A), which serves as an oncogene in various types of cancer. The role of m6A modification in the onset and progression of cancer has attracted growing attention. However, the functional and regulatory mechanisms of METTL3 in non‑small cell lung cancer (NSCLC) progression are still poorly understood. In the present study, METTL3 expression in NSCLC tissue was analyzed using the Gene Expression Profiling Interactive Analysis database. Western blotting and reverse transcription‑quantitative PCR were performed to evaluate the expression of METTL3 in NSCLC tissue and cell lines. Here, knockdown and overexpression of METTL3 notably decreased NSCLC cell viability, apoptosis and migration in vitro and, as well as tumorigenicity in vivo. Expression of METTL3 was upregulated in NSCLC tissue. METTL3 overexpression promoted cell viability and migration in NSCLC, while knockdown of METTL3 yielded the opposite result in vivo and in vitro. METTL3 increased Bcl‑2 translation via m6A modification, which increased viability and enhanced migration of NSCLC cells. METTL3 served as an oncogene in NSCLC via METTL3‑mediated Bcl‑2 mRNA m6A modification, which indicated that targeting METTL3 may be an effective therapeutic strategy for clinical management of NSCLC.

Bio- and Hemo-Compatible Silk Fibroin PEGylated Nanocarriers for 5-Fluorouracil Chemotherapy in Colorectal Cancer: In Vitro Studies

5-fluorouracil (5-FU) remains the gold standard of treatment for colorectal cancer, but its poor bioavailability and high systemic toxicity highlight the urgent need for the development of novel delivery strategies to increase the efficacy of 5-FU treatment. The present study is aimed to design and validate a PEGylated Silk Fibroin Nanocarrier (SF/PEG nanoparticles (NPs)) as an efficient 5-FU delivery system for potential intravenous administration. Using the human adenocarcinoma HT–29 cell line as an in vitro model for colorectal cancer, the cytotoxicity screening of the SF/PEG NPs showed that pristine nanocarriers were highly biocompatible, while the addition of 5-FU triggers a dramatic reduction in tumor cell viability, proliferation potential and mitochondrial integrity as well as a significant increase in nitric oxide production. Despite their high in vitro cytotoxicity, the 5-FU SF/PEG NPs were found hemocompatible as no impact on red blood cells hemolysis or the phagocytic activity of the granulocytes was observed. Exposure of HT–29 tumor cells and blood samples to 5-FU SF/PEG NPs augmented the tumor necrosis factor-α levels. Moreover, 5-FU SF/PEG NPs showed an impact on tumor cell migration and invasive potential as both of these processes were inhibited by the NP treatment.

Molecular mechanisms of anticancer effect of rutin

Because of the extensive biological functions of natural substances such as bioflavonoids, and their high safety and low costs, they could have high priority application in the health care system. The antioxidant properties of rutin, a polyphenolic bioflavonoid, have been well documented and demonstrated a wide range of pharmacological applications in cancer research. Since chemotherapeutic drugs have a wide range of side effects and rutin is a safe anticancer agent with minor side effects so recent investigations are performed for study of mechanisms of its anticancer effect. Both in-vivo and in-vitro examinations on anticancer mechanisms of this natural agent have been widely carried out. Regulation of different cellular signaling pathways such as Wnt/β-catenin, p53-independent pathway, PI3K/Akt, JAK/STAT, MAPK, p53, apoptosis as well as NF-ĸB signaling pathways helps to mediate the anticancer impacts of this agent. This study tried to review the molecular mechanisms of rutin anticancer effect on various types of cancer. Deep exploration of these anticancer mechanisms can facilitate the development of this beneficial compound for its application in the treatment of different cancers.

Biological and Therapeutic Effects of Troxerutin: Molecular Signaling Pathways Come into View

Flavonoids consist a wide range of naturally occurring compounds which are exclusively found in different fruits and vegetables. These medicinal herbs have a number of favourable biological and therapeutic activities such as antioxidant, neuroprotective, renoprotective, anti-inflammatory, anti-diabetic and anti-tumor. Troxerutin, also known as vitamin P4, is a naturally occurring flavonoid which is isolated from tea, coffee and cereal grains as well as vegetables. It has a variety of valuable pharmacological and therapeutic activities including antioxidant, anti-inflammatory, anti-diabetic and anti-tumor. These pharmacological impacts have been demonstrated in in vitro and in vivo studies. Also, clinical trials have revealed the efficacy of troxerutin for management of phlebocholosis and hemorrhoidal diseases. In the present review, we focus on the therapeutic effects and biological activities of troxerutin as well as its molecular signaling pathways.

The Protective Roles and Molecular Mechanisms of Troxerutin (Vitamin P4) for the Treatment of Chronic Diseases: A Mechanistic Review

Troxerutin (TRX), a semi-synthetic bioflavonoid derived from rutin, has been reported to exert several pharmacological effects including antioxidant, anti-inflammatory, antihyperlipidemic, and nephroprotective. However, the related molecular details and its mechanisms remain poorly understood. In the present review, we presented evidences from the diversity in vitro and in vivo studies on the therapeutic potential of TRX against neurodegenerative, diabetes, cancer and cardiovascular diseases with the purpose to find molecular pathways related to the treatment efficacy. TRX has a beneficial role in many diseases through multiple mechanisms including, increasing antioxidant enzymes and reducing oxidative damage, decreasing in proapoptotic proteins (APAF-1, BAX, caspases-9 and-3) and increasing the antiapoptotic BCL-2, increasing the nuclear translocation of nuclear factor erythroid 2-related factor 2 (Nrf2) and downregulating the nuclear factor κB (NFκ). TRX also reduces acetylcholinesterase activity and upregulates phosphoinositide 3- kinase/Akt signaling pathway in Alzheimer's disease models. Natural products such as TRX may develop numerous and intracellular pathways at several steps in the treatment of many diseases. Molecular mechanisms of action are revealing novel, possible combinational beneficial approaches to treat multiple pathological conditions.

Combined Effects of Protocatechuic Acid and 5-Fluorouracil on p53 Gene Expression and Apoptosis in Gastric Adenocarcinoma Cells

Objectives

This study evaluated the combined effects of protocatechuic acid (PCA) and 5-fluorouracil (5-FU) on gastric adenocarcinoma (AGS) cells.

Materials and Methods

The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, colony formation assay, flow cytometry technique, real-time quantitative polymerase chain reaction, and Western blotting were used to investigate cytotoxic effects, colony formation, apoptosis, p53 gene expression, and Bcl-2 protein level in AGS cells treated with 5-FU and PCA.

Results

Our results demonstrated that PCA (500 μM) alone or in combination with 5-FU (10 μM) inhibited AGS cell proliferation, inhibited a colony formation, and increased apoptosis compared with untreated control cells. Moreover, the combined 5-FU/PCA exposure led to upregulation of p53 and downregulation of Bcl-2 protein when compared to the untreated control cells.

Conclusion

The results demonstrate that the combined 5-FU/PCA may promote antiproliferative and pro-apoptotic effects with the inhibition of colony formation in AGS cells. The mechanisms by which the combined 5-FU/PCA exposure exerts its effects are associated with upregulation of p53 gene expression and downregulation of Bcl-2 level. Therefore, the combination of 5-FU with PCA not only could be a promising approach to potentially reduce the dose requirements of 5-FU but also could promote apoptosis via p53 and Bcl-2 signaling pathways.

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.

Interleukin-1 receptor antagonist enhances chemosensitivity to fluorouracil in treatment of Kras mutant colon cancer

BACKGROUND

Kras mutant colon cancer shows abnormal activation of the nuclear factor kappa-B (NF-κB) pathway, resulting in the proliferation of tumor cells. Treatment with fluorouracil (5-FU) might not achieve the expected inhibition of proliferation of malignant cells based on the fluorouracil-induced activation of the NF-κB pathway.

AIM

To detect whether interleukin (IL)-1 receptor antagonist (IL-1RA) could increase the chemosensitivity to 5-FU by decreasing the activation of the NF-κB pathway and reducing the proliferation of colon cancer cells.

METHODS

Western blot analysis was performed to detect the persistent activation of the NF-κB pathway in colon cancer cell lines. Reverse transcription-polymerase chain reaction was used to detect the IL-1RA-reduced expression levels of IL-6, IL-8, IL-17, IL-21 and TLR4 in colon cancer cell lines. We used a xenograft nude mouse model to demonstrate the downregulation of the NF-κB pathway by blocking the NF-κB-regulated IL-1α feedforward loop, which could increase the efficacy of chemotherapeutic agents in inhibiting tumor cell growth.

RESULTS

IL-1 receptor antagonist could decrease the expression of IL-1α and IL-1β and downregulate the activity of the NF-κB pathway in Kras mutant colon cancer cells. Treatment with 5-FU combined with IL-1RA could increase the chemosensitivity of the SW620 cell line, and decreased expression of the TAK1/NF-κB and MEK pathways resulted in limited proliferation in the SW620 cell line.

CONCLUSION

Adjuvant chemotherapy with IL-1RA and 5-FU has a stronger effect than single chemotherapeutic drugs. IL-1RA combined with fluorouracil could be a potential neoadjuvant chemotherapy in the clinic.

Upregulation of miRNA‑301a‑3p promotes tumor progression in gastric cancer by suppressing NKRF and activating NF‑κB signaling

MicroRNA‑301a (miRNA/miR‑301a) and nuclear factor (NF)‑κB signaling play important roles in tumor invasion, migration and progression. However, the role of miRNA‑301a‑3p in human gastric cancer (GC), and specifically in the activation of NF‑κB signaling, remains unclear. The aim of the present study was to investigate miRNA‑301a‑3p expression in GC progression and the molecular mechanisms as regards the regulation of NF‑κB signaling. Reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was used to detect miRNA‑301a‑3p expression in GC and paired normal tissues. The association between the expression of miRNA‑301a‑3p and patient pathological parameters and the prognosis of GC was statistically analyzed using an in situ hybridization (ISH) assay. An MTS assay and a Transwell assay were performed to evaluate the effects of miRNA‑301a‑3p on the proliferation, invasion and migration of GC cells. RT‑qPCR and western blot analysis were used to analyze the association between miRNA‑301a‑3p and nuclear factor‑κB repressing factor (NKRF) expression and the corresponding downstream NF‑κB signaling molecules. A luciferase assay was used to verify the target effect of miRNA‑301a‑3p and NKRF. It was found that miRNA‑301a‑3p expression was significantly higher in 30 cases of primary GC compared with matched normal tissues. Additionally, the ISH assay indicated that the high expression of miRNA‑301a‑3p in GC was associated with tumor invasion depth, lymph node metastasis, lymph node invasion and tumor metastasis stage. Patients whose tumors had a higher miRNA‑301a‑3p expression level exhibited a poorer prognosis. The in vitro assay indicated that miRNA‑301a‑3p affected the proliferative and invasive ability of GC cells by targeting the expression of NKRF, which then affected NF‑κB signaling. Therefore, it was hypothesize that miRNA‑301a‑3p promotes GC progression and affects the prognosis of patients with GC by targeting NKRF, which in turn, directly influences NF‑κB activation.

STAT3 Pathway in Gastric Cancer: Signaling, Therapeutic Targeting and Future Prospects

Molecular signaling pathways play a significant role in the regulation of biological mechanisms, and their abnormal expression can provide the conditions for cancer development. The signal transducer and activator of transcription 3 (STAT3) is a key member of the STAT proteins and its oncogene role in cancer has been shown. STAT3 is able to promote the proliferation and invasion of cancer cells and induces chemoresistance. Different downstream targets of STAT3 have been identified in cancer and it has also been shown that microRNA (miR), long non-coding RNA (lncRNA) and other molecular pathways are able to function as upstream mediators of STAT3 in cancer. In the present review, we focus on the role and regulation of STAT3 in gastric cancer (GC). miRs and lncRNAs are considered as potential upstream mediators of STAT3 and they are able to affect STAT3 expression in exerting their oncogene or onco-suppressor role in GC cells. Anti-tumor compounds suppress the STAT3 signaling pathway to restrict the proliferation and malignant behavior of GC cells. Other molecular pathways, such as sirtuin, stathmin and so on, can act as upstream mediators of STAT3 in GC. Notably, the components of the tumor microenvironment that are capable of targeting STAT3 in GC, such as fibroblasts and macrophages, are discussed in this review. Finally, we demonstrate that STAT3 can target oncogene factors to enhance the proliferation and metastasis of GC cells.

Combining an in silico approach with an animal experiment to investigate the protective effect of troxerutin for treating acute lung injury

Background

Troxerutin (TRX), a naturally occurring flavonoid in various fruits, has been reported to exhibit numerous pharmacological and biological activities in vitro and in vivo. However, the molecular mechanisms underlying TRX as a treatment for disease are poorly understood.

Methods

Using pharmacophore mapping and inverse docking, a set of potential TRX target proteins that have been associated with multiple forms of diseases was obtained. Bioinformatic analyses were performed using the Enrichr and STRING servers to analyse the related biological processes and protein-protein networks. Furthermore, we investigated the potential protective effect of TRX against lipopolysaccharide-induced acute lung injury (ALI) using a mouse model. Morphological changes in the lungs were assessed using haematoxylin and eosin staining. Inflammatory cytokines, tumour necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6 and IL-10 were investigated using ELISA. Activation of MAPK and NF-κB was detected using western blotting.

Results

Our network pharmacology analysis revealed the existence of multiple TRX-related chemical-target interactions and the related biological processes. We found that pretreatment with TRX protected against histological changes and obviously regulated the inflammatory cell counts and inflammatory cytokine levels in bronchoalveolar lavage fluid. Based on bioinformatic and western blot analyses, TRX may exert a protective effect against ALI by inhibiting MAPK and NF-κB signalling.

Conclusions

TRX can ameliorate pulmonary injury by inhibiting the MAPK and NF-κB signalling pathways and has a potential protective effect against ALI. This study may be helpful for understanding the mechanisms underlying TRX action and for discovering new drugs from plants for the treatment of ALI.

Electronic supplementary material

The online version of this article (10.1186/s12906-019-2515-7) contains supplementary material, which is available to authorized users.

TFAP2E methylation promotes 5‑fluorouracil resistance via exosomal miR‑106a‑5p and miR‑421 in gastric cancer MGC‑803 cells

Hypermethylation of transcription factor activating enhancer-binding protein 2e (TFAP2E) has been reported to be associated with chemoresistance to 5-fluorouracil (5-FU) in gastric cancer (GC). In the present study, the molecular mechanism governing this chemoresistance was investigated. Drug-resistant human GC MGC-803/5-FU cells were established and TFAP2E expression and methylation levels were assessed. Autocrine exosomes from GC culture medium were isolated and characterized. MicroRNA (miRNA) microarray analysis was used to determine the miRNA expression profile of GC cell-derived exosomes. Exosomes collected from MGC-803/5-FU cells were co-cultured with control cells, and 5-Aza-2′-deoxycytidine (5Aza) was added into MGC-803/5-FU cells to investigate the relationship between TFAP2E, exosomes and chemosensitivity. In the present study, it was demonstrated that hypermethylation of TFAP2E resulted in its reduced expression and 5-FU chemoresistance in GC cells. miRNAs miR-106a-5p and miR-421 were highly expressed and regulated the chemoresistance induced by TFAP2E methylation. Target gene prediction using miRBase, TargetScan and PicTar revealed that E2F1, MTOR and STAT3 may be TFAP2E target genes in GC. Collectively, our data support an important role of exosomes and exosomal miRNAs in TFAP2E methylation-induced chemoresistance to 5-FU in GC. These results highlight their potential for miRNA-based therapeutics.

Extract of Cycas revoluta Thunb. enhances the inhibitory effect of 5-fluorouracil on gastric cancer cells through the AKT-mTOR pathway

BACKGROUND

Gastric cancer is one of the most common and deadly malignancies worldwide. Despite recent medical progress, the 5-year survival rate of gastric cancer is still unsatisfactory. 5-fluorouracil (5-Fu) is one of the first-line antineoplastic treatments for gastric cancer, as it can effectively induce cancer cell apoptosis. However, the effect of 5-Fu is limited due to drug resistance of the malignant tumor. Previous studies have reported that Sotetsuflavone from Cycas revoluta Thunb. can markedly suppress lung cancer cell proliferation by apoptosis, though its effect on gastric cancer remains unknown.

AIM

To investigate the inhibitory effect of Cycas revoluta Thunb. and to determine whether it can overcome gastric cancer cell drug resistance to 5-Fu.

METHODS

Cell viability was examined to determine whether the natural extract of Cycas revoluta Thunb. induced gastric cancer cell death. The half-maximal effective concentration and the half-maximal lethal concentration were calculatede. Wound-healing and transwell assays were performed to examine gastric cancer cell motility. Clonogenic assays were performed to investigate the synergistic effects of Cycas revoluta Thunb. with 5-Fu, and apoptotic bodies were detected by Hoechst staining. Western blotting was performed to examine the expression of related proteins and to investigate the molecular mechanism of Cycas revoluta Thunb.-induced cancer cell apoptosis. The expressions of proteins, including mammalian target of rapamycin (mTOR) and p-AKT, were detected in different combinations of treatments for 48 h, then analyzed by ECL detection.

RESULTS

Gastric cancer cells were more sensitive to the natural extract of Cycas revoluta Thunb. compared to normal gastric epithelial cells, and the extract effectively inhibited gastric cancer cell migration and invasion. The extract improved the anti-cancer effect of 5-Fu by enhancing the chemosensitization of gastric cancer cells. Extract plus 5-Fu further reduced the expression of the drug-resistance-related proteins p-AKT and mTOR after 48 h compared to 5-Fu alone. Compared to 5-Fu treatment alone, mTOR and p-AKT expression was significantly reduced by about 50% and 75%, respectively. We also found that the natural extract of Cycas revoluta Thunb. further increased 5-Fu-induced gastric cancer cell apoptosis. Expression of apoptosis-related protein X-linked inhibitor of apoptosis protein and apoptosis inducing factor were significantly reduced and increased, respectively, in the 5-Fu-resistant gastric cancer line SGC-7901/R treated with extract plus 5-Fu, while the expression of survivin did not change.

CONCLUSION

The natural extract of Cycas revoluta Thunb. effectively inhibited gastric cancer cell growth and enhanced the anti-cancer effect of 5-Fu through the AKT-mTOR pathway.

Cripto Enhances Proliferation and Survival of Mesenchymal Stem Cells by Up-Regulating JAK2/STAT3 Pathway in a GRP78-Dependent Manner

Cripto is a small glycosylphosphatidylinositol-anchored signaling protein that can detach from the anchored membrane and stimulate proliferation, migration, differentiation, vascularization, and angiogenesis. In the present study, we demonstrated that Cripto positively affected proliferation and survival of mesenchymal stem cells (MSCs) without affecting multipotency. Cripto also increased expression of phosphorylated janus kinase 2 (p-JAK2), phosphorylated signal transducer and activator of transcription 3 (p-STAT3), 78 kDa glucose-regulated protein (GRP78), c-Myc, and cyclin D1. Notably, treatment with an anti-GRP78 antibody blocked these effects. In addition, pretreatment with STAT3 short interfering RNA (siRNA) inhibited the increase in p-JAK2, c-Myc, cyclin D1, and BCL3 levels caused by Cripto and attenuated the pro-survival action of Cripto on MSCs. We also found that incubation with Cripto protected MSCs from apoptosis caused by hypoxia or H₂O₂ exposure, and the level of caspase-3 decreased by the Cripto-induced expression of B-cell lymphoma 3-encoded protein (BCL3). These effects were sensitive to down-regulation of BCL3 expression by BCL3 siRNA. Finally, we showed that Cripto enhanced expression levels of vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF), and hepatocyte growth factor (HGF). In summary, our results demonstrated that Cripto activated a novel biochemical cascade that potentiated MSC proliferation and survival. This cascade relied on phosphorylation of JAK2 and STAT3 and was regulated by GRP78. Our findings may facilitate clinical applications of MSCs, as these cells may benefit from positive effects of Cripto on their survival and biological properties.

Apoptosis-inducing effects and growth inhibitory of a novel chalcone, in human hepatic cancer cells and lung cancer cells

Apoptosis is an important biological phenomenon, which affects many diseases, such as cancer and Alzheimer's disease. In the present study, we observed that chalcone 9X, an aromatic ketone, induced apoptosis of human hepatic and lung cancer cells and inhibited cancer cell migration and invasion. This compound strongly suppressed the growth of tumor in a mouse model of xenograft tumors. The anticancer activity of chalcone 9X was equivalent to 5-fluorouracil (5-FU) as a positive control agent, whereas the toxic effect of chalcone 9X in non-cancer cells was weaker than 5-FU. Molecular docking results showed that chalcone 9X could act on the active sites of pro-apoptotic proteins capspases-3 and -8 to induce apoptotic death of cancer cells. Our findings suggest that chalcone 9X might be considered a candidate compound of novel anticancer drug in the future.

Troxerutin, a mixture of O-hydroxyethyl derivatives of the natural flavonoid rutin: Chemical stability and analytical aspects

Troxerutin (TRX) is a mixture of semisynthetic hydroxyethylrutosides (Hers) arising from hydroxyethylation of rutin, a natural occurring flavonoid. TRX is commonly used for its anti-oxidant and anti-inflammatory properties in chronic venous insufficiency and other vascular disorders. In recent studies, the protective effects of TRX in Alzheimer's disease, colon carcinogenesis and hepatocellular carcinoma are emerged. However, the chemical stability of TRX has never been studied. Hence, the aims of the work were to study the TRX chemical stability through a forced degradation study and to develop and validate a new stability indicating LC-UV method for determination of TRX. In order to perform the study, TRX stability was tested in various stress conditions analysing the degradation samples by LC-MS. Three degradation products (DPs; D1, D2 and D3, 3',4',7-Tri-O-(β-hydroxyethyl)quercetin, 3',4',5,7-Tetra-O-(β-hydroxyethyl)quercetin and 3',4'-Di-O-(β-hydroxyethyl)quercetin respectively) arising from degradation in acidic conditions were identified and synthesized: among them, D1 resulted the stability indicator for hydrolytic degradation. Furthermore, a stability-indicating LC-UV method for simultaneous determination of triHer (3',4',7-Tri-O-(β-hydroxyethyl)rutin, the principal component of the mixture) and D1 was developed and validated. The LC-UV method consisted in a gradient elution on a Phenomenex Kinetex EVO C18 (150 × 3 mm, 5 μm) with acetonitrile and ammonium bicarbonate buffer (10 mM, pH 9.2). The method was linear for triHer (20-60 μg mL^-1) and D1 (5.1-35 μg mL^-1). The intraday and interday precision were determined and expressed as RSDs: all the values were ≤ 2% for both triHer and D1. The method demonstrated also to be accurate and robust and the average recoveries were 98.8 and 97.9% for triHer and D1, respectively. Moreover, the method resulted selective and specific for all of the components present in the degradation pattern of TRX (diHer (3',4'-Di-O-(β-hydroxyethyl)rutin), triHer, tetraHer (3',4',5,7-Tetra-O-(β-hydroxyethyl)rutin), D3, D1 and D2) and it was successfully applied for the stability studies of both drug substances and drug products.

Role of ATP-binding cassette transporters, apoptosis, and long non-coding RNAs in gastric cancer multidrug resistance

Cancer multidrug resistance refers to the cross resistance of cancer cells to a variety of anticancer drugs, which can be primary or secondary. Several mechanisms attribute to cancer multidrug resistance. In this paper, the recent progress in the understanding of the mechanisms of multi-drug resistance of gastric cancer cells with regard to the role of adenosine triphosphate binding cassette transporters, apoptosis, and long non-coding RNAs is reviewed.