Toll-like receptor 2 stimulation promotes colorectal cancer cell growth via PI3K/Akt and NF-κB signaling pathways

Toll-like receptors in health and disease

Toll-like receptors (TLRs) are inflammatory triggers and belong to a family of pattern recognition receptors (PRRs) that are central to the regulation of host protective adaptive immune responses. Activation of TLRs in innate immune myeloid cells directs lymphocytes to produce the most appropriate effector responses to eliminate infection and maintain homeostasis of the body's internal environment. Inappropriate TLR stimulation can lead to the development of general autoimmune diseases as well as chronic and acute inflammation, and even cancer. Therefore, TLRs are expected to be targets for therapeutic treatment of inflammation-related diseases, autoimmune diseases, microbial infections, and human cancers. This review summarizes the recent discoveries in the molecular and structural biology of TLRs. The role of different TLR signaling pathways in inflammatory diseases, autoimmune diseases such as diabetes, cardiovascular diseases, respiratory diseases, digestive diseases, and even cancers (oral, gastric, breast, colorectal) is highlighted and summarizes new drugs and related clinical treatments in clinical trials, providing an overview of the potential and prospects of TLRs for the treatment of TLR-related diseases.

Mechanisms by which the intestinal microbiota affects gastrointestinal tumours and therapeutic effects

The intestinal microbiota is considered to be a forgotten organ in human health and disease. It maintains intestinal homeostasis through various complex mechanisms. A significant body of research has demonstrated notable differences in the gut microbiota of patients with gastrointestinal tumours compared to healthy individuals. Furthermore, the dysregulation of gut microbiota, metabolites produced by gut bacteria, and related signal pathways can partially explain the mechanisms underlying the occurrence and development of gastrointestinal tumours. Therefore, this article summarizes the latest research progress on the gut microbiota and gastrointestinal tumours. Firstly, we provide an overview of the composition and function of the intestinal microbiota and discuss the mechanisms by which the intestinal flora directly or indirectly affects the occurrence and development of gastrointestinal tumours by regulating the immune system, producing bacterial toxins, secreting metabolites. Secondly, we present a detailed analysis of the differences of intestinal microbiota and its pathogenic mechanisms in colorectal cancer, gastric cancer, hepatocellular carcinoma, etc. Lastly, in terms of treatment strategies, we discuss the effects of the intestinal microbiota on the efficacy and toxic side effects of chemotherapy and immunotherapy and address the role of probiotics, prebiotics, FMT and antibiotic in the treatment of gastrointestinal tumours. In summary, this article provides a comprehensive review of the pathogenic mechanisms of and treatment strategies pertaining to the intestinal microbiota in patients with gastrointestinal tumours. And provide a more comprehensive and precise scientific basis for the development of microbiota-based treatments for gastrointestinal tumours and the prevention of such tumours.

Antitumor activity of 5-fluorouracil polymeric nanogel synthesized by gamma radiation on a rat model of colon carcinoma: a proposed mechanism

The use of 5-fluorouracil (5-FU) is associated with multifaceted challenges and poor pharmacokinetics. Accordingly, our study was designed to prepare 5-FU nanogel as a new form of the colon cancer chemotherapeutic drug 5-FU using polyacrylic acid and gelatin hybrid nanogel as efficient drug carriers. Alongside the in vivo chemotherapeutic evaluation, the anti-proliferative and anti-apoptotic efficacy were carried out for 5-FU nanogel against 1,2-dimethylhydrazine (DMH, 20 mg/kg) and γ-radiation (4 Gy)-prompted colon dysplasia in rats compared to 5-FU. The morphology and size of 5-FU nanogel were characterized by transmission electron microscopy (TEM) and dynamic light scattering (DLS) in addition to cytotoxicity assay. The expression of phosphoinositide-3-kinase (PI3K)/Akt, mammalian target of rapamycin (mTOR); Toll-like receptor2 (TLR2)/nuclear factor kappa B), adenosine monophosphate (AMP)-activated protein kinase (AMPK) and its downstream autophagy-related genes in addition to apoptotic markers were measured in colon tissues. Results: 5-FU nanogel reduced the levels of the TLR2/ NF-κβ as well as the expression of PI3K/AKT/mTOR. Moreover, it promoted autophagy through the activation of the AMPK and its downstream targets which consequently augmented the intrinsic and extrinsic apoptotic pathways. Conclusion: Collectively, these data might strengthen the therapeutic potential of 5-FU nanogel which can be used as an antitumor product for colon cancer.

Dietary fiber as a wide pillar of colorectal cancer prevention and adjuvant therapy

Colorectal cancer is the third most incident and second most lethal type of cancer worldwide. Lifestyle and dietary patterns are the key factors for higher disease development risk. The dietary fiber intake from fruits and vegetables, mainly formed by food hydrocolloids, can help to lower the incidence of this type of neoplasia. Different food polysaccharides have applications in anti-tumoral therapy, such as coadjuvant to mainstream drugs, carriage-like properties, or direct influence on tumoral cells. Some classes include inulin, β-glucans, pectins, fucoidans, alginates, mucilages, and gums. Therefore, it is fundamental to discuss colorectal cancer mechanisms and the roles played by different polysaccharides in intestinal health. Genetic, environmental, and immunological modulation of mutated pathways regarding colorectal cancer has been explored before. Microbial diversity, byproduct formation (primarily short-chain fatty acids), inflammatory profile control, and tumoral mutated pathways regulation are thoroughly explored mechanisms by which dietary fiber sources influence a healthy gut ambiance.

WNT1 Inducible Signaling Pathway Protein 1 Is a Stroma-Specific Secreting Protein Inducing a Fibroblast Contraction and Carcinoma Cell Growth in the Human Prostate

The WNT1 inducible signaling pathway protein 1 (WISP1), a member of the connective tissue growth factor family, plays a crucial role in several important cellular functions in a highly tissue-specific manner. Results of a RT-qPCR indicated that WISP1 expressed only in cells of the human prostate fibroblasts, HPrF and WPMY-1, but not the prostate carcinoma cells in vitro. Two major isoforms (WISP1v1 and WISP1v2) were identified in the HPrF cells determined by RT-PCR and immunoblot assays. The knock-down of a WISP1 blocked cell proliferation and contraction, while treating respectively with the conditioned medium from the ectopic WISP1v1- and WISPv2-overexpressed 293T cells enhanced the migration of HPrF cells. The TNFα induced WISP1 secretion and cell contraction while the knock-down of WISP1 attenuated these effects, although TNFα did not affect the proliferation of the HPrF cells. The ectopic overexpression of WISP1v1 but not WISP1v2 downregulated the N-myc downstream regulated 1 (NDRG1) while upregulating N-cadherin, slug, snail, and vimentin gene expressions which induced not only the cell proliferation and invasion in vitro but also tumor growth of prostate carcinoma cells in vivo. The results confirmed that WISP1 is a stroma-specific secreting protein, enhancing the cell migration and contraction of prostate fibroblasts, as well as the proliferation, invasion, and tumor growth of prostate carcinoma cells.

Biological roles of toll-like receptors and gut microbiota in colorectal cancer

Colorectal cancer (CRC) is one of the most considerably common malignancies of the alimentary system, with high mortality and incidence rates.  The present study suggested that the occurrence of CRC is closely related to bacteria, as the large intestine is a gathering place for human micro-organisms. However, the nosogenesis of bacteria leading to tumorigenesis is still obscure. Recently, many studies have reported that toll-like receptors and their related molecular pathways are involved in the process of gut micro-organisms generating CRC. Gut micro-organisms can promote or inhibit the development of CRC via binding to special toll-like receptors. In this paper, the authors review the relationship among toll-like receptors, gut micro-organisms and CRC in order to provide a reference for future tumor immunotherapy and targeted therapy.

Comprehensive Bioinformatics Analysis of Toll-Like Receptors (TLRs) in Pan-Cancer

Background

To conduct a comprehensive bioinformatics analysis on the transcriptome signatures of Toll-like receptors (TLRs) in pan-cancer. Materials and methods. A total of 11,057 tissues consisting of 33 types of carcinoma in The Cancer Genome Atlas (TCGA) were retrieved, and then we further explored the correlation between TLRs' expression with tumorigenesis, immune infiltration, and drug sensitivity. We conducted a comprehensive bioinformatics analysis on TLR1 to 10 in pan-cancer, including differential expression analysis between normal and tumor tissues, differential immune subtype correlation, survival analysis, tumor immune infiltration estimating, stemness indices correlation, and drug responses correlation.

Results

TLR2 was highly expressed in most types of tumors. TLR9 was hardly expressed compared to other TLR genes, which lead to TLR9 showing less correlation with both immune-estimate scores and stromal-estimate scores. All the TLRs were related with immune subtype of tumor samples that all of them were differentially expressed in differential immune subtype samples. The expression of TLRs was positively related with immune-estimate scores and stromal-estimate scores in almost all types of tumor. The expression of TLRs was negatively correlated with mRNA expression-based stemness scores (RNAss) in nearly almost type of tumors except kidney renal clear cell carcinoma (KIRC) and also negatively correlated with DNA methylation-based stemness scores (DNAss) in many types of tumors except adrenocortical carcinoma (ACC), cholangiocarcinoma (CHOL), KIRC, acute myeloid leukemia (LAML), low-grade glioma (LGG), testicular germ cell tumors (TGCT), thyroid carcinoma (THCA), thymoma (THYM), and uveal melanoma (UVM). The expression of TLR9 was significantly positively correlated with the drug sensitivity of fluphenazine, alectinib, carmustine, and 7−hydroxystaurosporine. TLR7 was significantly positively correlated with the drug sensitivity of alectinib.

Conclusions

Our study reveals the significant role of TLRs family in pan-cancer and provides potential therapeutic strategies of cancer.

Bacterial Translocation in Gastrointestinal Cancers and Cancer Treatment

In recent years, there has been increasing evidence that gut microbiota is associated with the onset and exacerbation of various diseases, such as gastrointestinal cancer. For instance, it is well known that local inflammation of the intestinal tract in colorectal cancer that is caused by the increased number of Fusobacterium, due to changes in the intestinal bacterial flora, is involved in carcinogenesis. In contrast, gut bacteria or their products, pathogen-associated molecular patterns, not only cause intestinal inflammation but also invade the bloodstream through dysbiosis and gut barrier dysfunction, thereby leading to systemic inflammation, namely bacterial translocation. The involvement of bacterial translocation in the carcinogenesis of gastrointestinal cancers and their prognosis is increasingly being recognized. The Toll-like receptor signaling pathways plays an important role in the carcinogenesis of such cancers. In addition, bacterial translocation influences the treatment of cancers such as surgery and chemotherapy. In this review, we outline the concept of bacterial translocation, summarize the current knowledge on the relationship between gut bacteria and gastrointestinal cancer, and provide future perspectives of this field.

The Association Between Gut Microbiota, Toll-Like Receptors, and Colorectal Cancer

The large number of microbes found in the gut are involved in various critical biological processes in the human body and have dynamic and complex interactions with the immune system. Disruptions in the host’s gut microbiota and the metabolites produced during fermentation promote the development of intestinal inflammation and colorectal cancer (CRC). Toll-like receptors (TLRs) recognize specific microbial-associated molecular patterns specific to microorganisms whose signaling is involved in maintaining intestinal homeostasis or, under certain conditions, mediating dysbiosis-associated intestinal inflammation. The signaling pathways of TLRs are described first, followed by a discussion of the interrelationship between gut microbes and TLRs, including the activation of TLRs by gut microbes and the effect of TLRs on the distribution of gut microbiota, particularly the role of microbes in colorectal carcinogenesis via TLRs. Finally, we discuss the potential roles of various TLRs in colorectal cancer.

Sparstolonin B exerts beneficial effects on prostate cancer by acting on the reactive oxygen species-mediated PI3K/AKT pathway

Prostate cancer is a major health concern in males worldwide, owing to its high incidence. Sparstolonin B (SsnB), a component of the Chinese herbal medicine Sparganium stoloniferum, is used to treat many diseases. However, the effects and mechanisms of action of SsnB in prostate cancer have not yet been reported. In this study, we evaluated the effects of SsnB on cellular processes and tumour growth. In particular, we verified that SsnB could inhibit the proliferation, migration and invasion of prostate cancer cells and induce apoptosis by activating G2/M phase arrest in vitro based on a series of cytological experiments. In vivo, we found that SsnB could inhibit tumour growth in nude mouse xenograft models. We further confirmed that SsnB could repress the PI3K/AKT pathway by increasing reactive oxygen species (ROS) accumulation and oxidative stress. Collectively, SsnB inhibits tumour growth and induces apoptosis in prostate cancer via the suppression of the ROS‐mediated PI3K/AKT pathway and may be a new alternative to adjuvant therapy for prostate cancer.

Ganglioside GT1b increases hyaluronic acid synthase 2 via PI3K activation with TLR2 dependence in orbital fibroblasts from thyroid eye disease patients

Thyroid eye disease (TED) is a complex autoimmune disease with a spectrum of signs. we previously reported that trisialoganglioside (GT)1b is significantly overexpressed in the orbital tissue of TED patients, and that exogenous GT1b strongly induced HA synthesis in orbital fibroblasts. However, the signaling pathway in GT1b-induced hyaluronic acid synthase (HAS) expression in orbital fibroblasts from TED patients have rarely been investigated. Here, we demonstrated that GT1b induced phosphorylation of Akt/mTOR in a dose-dependent manner in orbital fibroblasts from TED patients. Both co-treatment with a specific inhibitor for PI3K and siRNA knockdown of TLR2 attenuated GT1b-induced Akt phosphorylation. GT1b significantly induced HAS2 expression at both the transcriptional and translational level, which was suppressed by specific inhibitors of PI3K or Akt/mTOR, and by siRNA knockdown of TLR2. In conclusion, GT1b induced HAS2 in orbital fibroblasts from TED patients via activation of the PI3K-related signaling pathway, dependent on TLR2.

Temozolomide Treatment Induces HMGB1 to Promote the Formation of Glioma Stem Cells via the TLR2/NEAT1/Wnt Pathway in Glioblastoma

Formation of glioma stem cells (GSCs) is considered as one of the main reasons of temozolomide (TMZ) resistance in glioma patients. Recent studies have shown that tumor microenvironment-derived signals could promote GSCs formation. But the critical molecule and underlying mechanism for GSCs formation after TMZ treatment is not entirely identified. Our study showed that TMZ treatment promoted GSCs formation by glioma cells; TMZ treatment of biopsy-derived glioblastoma multiforme cells upregulated HMGB1; HMGB1 altered gene expression profile of glioma cells with respect to mRNA, lncRNA and miRNA. Furthermore, our results showed that TMZ-induced HMGB1 increased the formation of GSCs and when HMGB1 was downregulated, TMZ-mediated GSCs formation was attenuated. Finally, we showed that the effect of HMGB1 on glioma cells was mediated by TLR2, which activated Wnt/β-catenin signaling to promote GSCs. Mechanistically, we found that HMGB1 upregulated NEAT1, which was responsible for Wnt/β-catenin activation. In conclusion, TMZ treatment upregulates HMGB1, which promotes the formation of GSCs via the TLR2/NEAT1/Wnt pathway. Blocking HMGB1-mediated GSCs formation could serve as a potential therapeutic target for preventing TMZ resistance in GBM patients.

[Regulation of long non-coding RNA in cartilage injury of osteoarthritis]

Objective

To summarize the regulatory effect of long non-coding RNA (lncRNA) on osteoarthritis (OA) cartilage injury.

Methods

The molecular functions and mechanisms of lncRNA were introduced and its regulatory effects on the pathological processes of OA were elaborated by referring to the relevant literature at domestic and abroad in recent years.

Results

The pathological characteristics of OA are degeneration of articular cartilage and inflammation of synovial tissue, but its etiology and pathological mechanism have not been clarified. lncRNA is a kind of heterogeneous non-coding RNA, which plays a regulatory role in many inflammation-related diseases and exerts a wide range of biological functions. lncRNA is a regulator involved in the pathogenesis of OA, and is abnormally expressed in OA cartilage, leading to the degeneration of the extracellular matrix of cartilage.

Conclusion

At present, there have been preliminary studies on the pathological effects of lncRNA in regulating OA and the biological functions of chondrocytes. However, the pathogenesis of lncRNA and its regulatory network in OA and the way in which it regulates inflammatory pathways are still unclear, and further exploration is needed.

Signal transduction pathway mutations in gastrointestinal (GI) cancers: a systematic review and meta-analysis

The present study was conducted to evaluate the prevalence of the signaling pathways mutation rate in the Gastrointestinal (GI) tract cancers in a systematic review and meta-analysis study. The study was performed based on the PRISMA criteria. Random models by confidence interval (CI: 95%) were used to calculate the pooled estimate of prevalence via Metaprop command. The pooled prevalence indices of signal transduction pathway mutations in gastric cancer, liver cancer, colorectal cancer, and pancreatic cancer were 5% (95% CI: 3–8%), 12% (95% CI: 8–18%), 17% (95% CI: 14–20%), and 20% (95% CI: 5–41%), respectively. Also, the mutation rates for Wnt pathway and MAPK pathway were calculated to be 23% (95% CI, 14–33%) and 20% (95% CI, 17–24%), respectively. Moreover, the most popular genes were APC (in Wnt pathway), KRAS (in MAPK pathway) and PIK3CA (in PI3K pathway) in the colorectal cancer, pancreatic cancer, and gastric cancer while they were beta-catenin and CTNNB1 in liver cancer. The most altered pathway was Wnt pathway followed by the MAPK pathway. In addition, pancreatic cancer was found to be higher under the pressure of mutation compared with others based on pooled prevalence analysis. Finally, APC mutations in colorectal cancer, KRAS in gastric cancer, and pancreatic cancer were mostly associated gene alterations.

Toll-like Receptors as a Novel Therapeutic Target for Natural Products Against Chronic Diseases

Toll-like receptors (TLR) are one among the initial responders of the immune system which participate in the activation inflammatory processes. Several different types of TLR such as TLR2, TLR4, TLR7 and TLR9 have been identified in various cell types, each having distinct ligands like lipids, lipoproteins, nucleic acids and proteins. Though its prime concern is xenobiotic defences, TLR signalling has also recognized as an activator of inflammation and associated development of chronic degenerative disorders (CDDs) including obesity, type 2 diabetes mellitus (T2DM), fatty liver disease, cardiovascular and neurodegenerative disorders as well as various types of cancers. Numerous drugs are in use to prevent these disorders, which specifically inhibit different pathways associated with the development of CDDs. Compared to these drug targets, inhibition of TLR, which specifically responsible for the inflammatory insults has proven to be a better drug target. Several natural products have emerged as inhibitors of CDDs, which specifically targets TLR signalling, among these, many are in the clinical trials. This review is intended to summarize the recent progress on TLR association with CDDs and to list possible use of natural products, their combinations and their synthetic derivative in the prevention of TLR-driven CDD development.

Dysregulation of TLR2 Serves as a Prognostic Biomarker in Breast Cancer and Predicts Resistance to Endocrine Therapy in the Luminal B Subtype

Background: Breast cancer (BCa) is a serious global health burden among females, and the development of resistance represents an important challenge to BCa treatment. Here, we examined the expression of toll-like receptor 2 (TLR2) in BCa patients and the prognostic value of TLR2 for predicting endocrine resistance.

Methods: The study included 150 BCa patients, of which 82 underwent endocrine therapy. TLR2 mRNA expression was measured by quantitative Real-Time PCR, and its prognostic value was determined by Kaplan-Meier survival analysis. Changes in the expression of TLR2 in BCa patients with endocrine resistance were assessed, and the value of TLR2 for predicting endocrine resistance was evaluated using the receiver operating characteristic curve analysis.

Results: TLR2 expression was higher in BCa tissue than in normal tissue and associated with tumor size, HER2 status, tumor subtype, and TNM stage. TLR2 upregulation was associated with poor prognosis in patients with BCa, as well as endocrine resistance, and TLR2 upregulation was more prevalent among HER2-positive BCa cases. The predictive performance of TLR2 for endocrine resistance was higher in HER2-positive BCa than in other hormone receptor-positive BCa cases.

Conclusion: TLR2 upregulation is a promising biomarker for prognosis and predicting resistance to endocrine therapy. The relationship between TLR2 and HER2 indicates that TLR2 may be involved in endocrine resistance through the HER2 signaling pathway in BCa.

Effect of TLR2 on the proliferation of inflammation-related colorectal cancer and sporadic colorectal cancer

Background

Colitis-associated cancer (CAC) is a complication of inflammatory bowel disease (IBD) with a poor prognosis because it is often diagnosed in advanced stages with local progression or metastasis. Compared with the more common polyp-induced sporadic colorectal cancer (sCRC), CAC has different molecular mechanisms. Toll-like receptor 2 (TLR2) expression is not limited to cells related to inflammation and immune function. High levels of TLR2 expression in tumor tissues of colorectal cancer (CRC) patients have been reported. This report is to investigate the effects of knockout and knockdown of the TLR2 gene on the proliferation of CAC and sCRC.

Methods

Twelve C57BL/6 J wild-type mice (WT) and 12 TLR2 knockout mice (TLR2-/-) were used to rapidly establish a colitis-associated cancer (CAC) model via the 1,2-dimethylhydrazine-dextran sodium sulfate (DMH-DSS) method and were divided into the normal WT control group (NC), TLR2 knockout control group (KC), normal wild-type tumor modeling group (NT), and TLR2 knockout tumor modeling group (KT), with 6 mice in each group. The general performance of the mice during modeling, the gross changes of the colon and the rectum, and the pathological score of HE staining were used to observe tumor growth. The expression of TLR2 was detected by immunohistochemistry, and tumor proliferation was detected by Ki67 labeling. Lentivirus carrying TLR2-RNAi was used to stably infect colorectal cancer cells (HCT116 and HT29) to knock down TLR2 gene expression. The experimental groups included the uninfected control group, negative control group, and gene knockdown group. After infection, the expression of TLR2 protein was detected by Western blot, and cell proliferation and the cell cycle were detected by the CCK-8 method and fluorescence-activated cell sorting. Western blot was used to detect the expression levels of p- NF-κβ, cyclin D1 and cyclin D3 protein in each group of cells.

Results

TLR2 knockout in the CAC model resulted in greater changes in body weight and more severe diarrhea and colorectal hemorrhage. However, knocking out the TLR2 gene reduced the shortening of colorectal length, the number of tumors, and the total tumor volume and inhibited the growth of CAC. Knocking out the TLR2 gene also reduced the pathological score and tumor severity. TLR2 was localized in the cell membrane of the colorectal epithelium of the NC group and of the colorectal tumors of the NT group and was highly expressed in the NT group, while antigen Ki67 was localized in the nucleus of the colorectal tumor cells of the NT group and the KT group, and its expression was reduced in the KT group. In an in vitro sporadic colorectal cancer cell experiment, TLR2 protein in the TLR2 knockdown group was significantly downregulated, and TLR2 knockdown significantly inhibited the proliferation of HCT116 and HT29 colorectal cancer cells, resulting in G1 phase arrest. The expression levels of p-NF-κβ, cyclin D1 and cyclin D3 proteins in TLR2 gene knockdown group cells were significantly reduced.

Conclusion

Knockout and knockdown of TLR2 can inhibit the proliferation of inflammation-related colorectal cancer and sporadic colorectal cancer.

Toll-like receptors: exploring their potential connection with post-operative infectious complications and cancer recurrence

Cancer is the leading cause of death in North America. Despite modern advances in cancer therapy, many patients will ultimately develop cancer metastasis resulting in mortality. Surgery to resect early stage solid malignancies remains the cornerstone of cancer treatment. However, surgery places patients at risk of developing post-operative infectious complications that are linked to earlier cancer metastatic recurrence and cancer mortality. Toll-like receptors (TLRs) are evolutionarily-conserved sentinel receptors of the innate immune system that are activated by microbial products present during infection, leading to activation of innate immunity. Numerous types of solid cancer cells also express TLRs, with their activation augmenting their ability to metastasize. Similarly, healthy host-tissue TLRs activated during infection induce a prometastatic environment in the host. Cancer cells additionally secrete TLR activating ligands that activate both cancer TLRs and host TLRs to promote metastasis. Consequently, TLRs are an attractive therapeutic candidate to target infection-induced cancer metastasis and progression.

Cancer immunotherapy with immunoadjuvants, nanoparticles, and checkpoint inhibitors: Recent progress and challenges in treatment and tracking response to immunotherapy

Chemotherapy, surgery, and radiation are accepted as the preferred treatment modalities against cancer, but in recent years the use of immunotherapeutic approaches has gained prominence as the fourth treatment modality in cancer patients. In this approach, a patient's innate and adaptive immune systems are activated to achieve clearance of occult cancerous cells. In this review, we discuss the preclinical and clinical immunotherapeutic (e.g., immunoadjuvants (in-situ vaccines, oncolytic viruses, CXC antagonists, device activated agents), organic and inorganic nanoparticles, and checkpoint blockade) that are under investigation for cancer therapy and diagnostics. Additionally, the innovations in imaging of immune cells for tracking therapeutic responses and limitations (e.g., toxicity, inefficient immunomodulation, etc.) are described. Existing data suggest that if immune therapy is optimized, it can be a real and potentially paradigm-shifting cancer treatment frontier.

Nuclear Factor κB Signaling and Its Related Non-coding RNAs in Cancer Therapy

Nuclear factor κB (NF-κB) acts as a nuclear factor that is composed of five main subunits. It is a pluripotent and crucial dimer transcription factor that has a close relationship with many serious illnesses, especially its influences on cell proliferation, inflammation, and cancer initiation and progression. NF-κB acts as part of the signaling pathway and determines its effect on the expression of several other genes, such as epidermal growth factor receptor (EGFR), p53, signal transducer and activator of transcription 3 (STAT3), and non-coding RNA (ncRNA). Continuous activation of the NF-κB signaling pathway has been seen in many cancer types. While the NF-κB signaling pathway is tightly regulated in physiological settings, quite frequently it is constitutively activated in cancer, and the molecular biology mechanism underlying the deregulated activation of NF-κB signaling remains unclear. In this review, we discuss the regulatory role and possible clinical significance of ncRNA (microRNA [miRNA] and long non-coding RNA [lncRNA]) in NF-κB signaling in cancer, including in the conversion of inflammation to carcinogenesis. Non-coding RNA plays an essential and complex role in the NF-κB signaling pathway. NF-κB activation can also induce the ncRNA status. Targeting NF-κB signaling by ncRNA is becoming a promising strategy of drug development and cancer treatment.

Construction and Validation of an Immune-Related Prognostic Model Based on TP53 Status in Colorectal Cancer

Growing evidence has indicated that prognostic biomarkers have a pivotal role in tumor and immunity biological processes. TP53 mutation can cause a range of changes in immune response, progression, and prognosis of colorectal cancer (CRC). Thus, we aim to build an immunoscore prognostic model that may enhance the prognosis of CRC from an immunological perspective. We estimated the proportion of immune cells in the GSE39582 public dataset using the CIBERSORT (Cell type identification by estimating relative subset of known RNA transcripts) algorithm. Prognostic genes that were used to establish the immunoscore model were generated by the LASSO (Least absolute shrinkage and selection operator) Cox regression model. We established and validated the immunoscore model in GEO (Gene Expression Omnibus) and TCGA (The Cancer Genome Atlas) cohorts, respectively; significant differences of overall survival analysis were found between the low and high immunoscore groups or TP53 subgroups. In the multivariable Cox analysis, we observed that the immunoscore was an independent prognostic factor both in the GEO cohort (HR (Hazard ratio) 1.76, 95% CI (confidence intervals): 1.26-2.46) and the TCGA cohort (HR 1.95, 95% CI: 1.20-3.18). Furthermore, we established a nomogram for clinical application, and the results suggest that the nomogram is a better predictive model for prognosis than immunoscore or TNM staging.

β-arrestin-2 up-regulates toll-like receptor 2 signaling and inhibits apoptosis in human endometrial cancer heterotransplants in nude mice

BACKGROUND

β-arrestin-2(Arr2) functions as an anti-apoptotic factor and affects cell proliferation, but its downstream molecular pathway in endometrial carcinoma (EC) is still unclear. This study aimed to investigate the effects of the stable overexpression of Arr2 on the proliferation and apoptosis of human EC heterotransplants and the expression of associated molecules, including Toll-like receptor 2(TLR2), serine-threonine kinase Akt (Akt), glycogen synthase kinase-3β(GSK3β) and some typical inflammatory cytokines such as NF-κB p56, TNF-α and IL-6 & IL-8.

METHODS

Human EC cell line Ishikawa, stably transfected with Arr2 full-length plasmid, was injected subcutaneously into nude mice. They were treated with 0, 10, 20 mg/kg paclitaxel and the volume and weight of the tumor tissue were measured and calculated. The necrotic index were assessed by H&E staining and microscopic observation. The levels of caspase-3, caspase-9, TLR2, NF-κB p56, Akt, GSK3β were measured by western blot, and the levels of TNF-α, IL-6, IL-8 were measured by real-time PCR.

RESULTS

We found that Arr2 overexpression promoted the growth of human EC heterotransplants. Arr2 attenuated the promotion of caspase-3 and caspase-9 by paclitaxel and mediated the increase of TLR2 and several inflammatory cytokines. The levels of Akt and GSK3β were not affected.

CONCLUSION

Arr2 overexpression was associated with the increase of TLR2 and several inflammatory factors, meanwhile inhibited paclitaxel-induced anti-tumor effect on human EC heterotransplants.

Toll-like receptor 6 expression, sequence variants, and their association with colorectal cancer risk

This is the first study to examine the potential correlation of the rs3796508 and rs5743810 SNPs of the TLR6 gene in patients with colorectal cancer (CRC) in a subset of the Saudi population. TLR6 gene expression was studied by real-time PCR assaysin 10 matching normal and cancer colon tissues. TLR6 expression at the protein level was determined by immunohistochemistry. A case-control search was conductedon 115 case patients and 102 controls. All samples were genotyped with the TaqMan assay for the TLR6 gene. Odds ratios and 95% confidence interval were computed from logistic regression models after adjusting for age, sex, and tumor localization. Our findings showed a decrease in TLR6 expression (p <0.001) in colon cancer tissues when compared to normal colon tissues. Global analysis revealed no significant association between the TLR6 rs3796508 and rs5743810 and CRC in this population. However, the Val/Met genotype of rs3796508 had a significantly higher frequency in the control group than in the cases for the male group (OR= 0.095, and p= 0.03385) or the volunteers aged more than 57 years OR= 0.152; and p= 0.04069, respectively). Two non-synonymous single nucleotide polymorphisms (SNP; S249P and V327M) were common in a few patients and were predicted as damaging by SIFT and Polyphen and were further analyzed for their protein stability and function using advanced bioinformatics tools. The results suggest that TLR6 rs3796508 has a crucial role as a protective factor against colorectal cancer in the older Saudi male population.

Targeted delivery of hesperetin to cartilage attenuates osteoarthritis by bimodal imaging with Gd2(CO3)3@PDA nanoparticles via TLR-2/NF-κB/Akt signaling

The progressive degeneration of cartilage marks the advancement of osteoarthritis (OA), which requires specific targeted treatment for effective cartilage repair. However, there is still no efficient cartilage delivery system or novel magnetic resonance (MR) contrast agent (CA). Herein, we report the synthesis of a novel class of MR CA, Gd₂(CO₃)₃-based nanoparticles (NPs), from a simpler and "greener" approach than previous ones. After the coating of polydopamine (PDA) onto the Gd₂(CO₃)₃ core, we further anchored a cartilage-targeting peptide and loaded hesperetin (Hes) into NPs (Hes-Gd₂(CO₃)₃@PDA-PEG-DWpeptide, HGdPDW), showing excellent cartilage affinity and MR suitability. Additionally, the synthesized HGdPDW exerted significant protective effects against IL-1β stimulation, as shown by the decreased apoptosis and inflammation and increased maturation of chondrocytes in vitro. More importantly, RNA-seq analyses showed the significant reduction of TLR-2 in IL-1β-treated chondrocytes, and this reduction was followed by the inactivation of NF-κB/Akt signaling, leading to the protective effect of HGdPDW. By the establishment of anterior cruciate ligament transection (ACLT) OA mice, the bimodal MRI/IVIS imaging demonstrated the effective cartilage-binding ability of HGdPDW in OA knees with low cytotoxicity, which alleviated the gradual degeneration of articular cartilage in vivo by inhibiting TLR-2 in chondrocytes. Taken together, these results suggest that HGdPDW could target cartilage effectively, thereby protecting chondrocytes from apoptosis and inflammation via TLR-2/NF-κB/Akt signaling. We hope this new class of MRI CA could be applied in not only other fields using MRI technology but also the treatment of general cartilage-related diseases; this application will undoubtedly extend the treatment of OA clinically.

WNT1-inducible signaling pathway protein 1 (WISP1/CCN4) stimulates melanoma invasion and metastasis by promoting the epithelial-mesenchymal transition

Besides intrinsic changes, malignant cells also release soluble signals that reshape their microenvironment. Among these signals is WNT1-inducible signaling pathway protein 1 (WISP1), a secreted matricellular protein whose expression is elevated in several cancers, including melanoma, and is associated with reduced survival of patients diagnosed with primary melanoma. Here, we found that WISP1 knockout increases cell proliferation and represses wound healing, migration, and invasion of mouse and human melanoma cells in multiple in vitro assays. Metastasis assays revealed that WISP1 knockout represses tumor metastasis of B16F10 and YUMM1.7 melanoma cells in both C57BL/6Ncrl and NOD-scid IL2Rγ^null (NSG) mice. WT B16F10 cells having an invasion phenotype in a transwell assay possessed a gene expression signature similar to that observed in the epithelial-mesenchymal transition (EMT), including E-cadherin repression and fibronectin and N-cadherin induction. Upon WISP1 knockout, expression of these EMT signature genes went in the opposite direction in both mouse and human cell lines, and EMT-associated gene expression was restored upon exposure to media containing WISP1 or to recombinant WISP1 protein. In vivo, Wisp1 knockout-associated metastasis repression was reversed by the reintroduction of either WISP1 or snail family transcriptional repressor 1 (SNAI1). Experiments testing EMT gene activation and inhibition with recombinant WISP1 or kinase inhibitors in B16F10 and YUMM1.7 cells suggested that WISP1 activates AKT Ser/Thr kinase and that MEK/ERK signaling pathways shift melanoma cells from proliferation to invasion. Our results indicate that WISP1 present within the tumor microenvironment stimulates melanoma invasion and metastasis by promoting an EMT-like process.

Knockdown of MON1B Exerts Anti-Tumor Effects in Colon Cancer In Vitro

Background

Colon cancer is one of the most common cancers in the world. We performed the present study to determine the molecular mechanism of MON1B in colon cancer cells.

Material/Methods

Colon cancer tissues and adjacent normal tissues were collected from 34 colon cancer patients. MON1B-silenced LoVo colon cancer cells were constructed. RT-qPCR and Western blot analysis were used to detect mRNA and protein levels, respectively, of colon cancer tissues and cells. Cell counting kit-8 (CCK-8), wound healing, and Transwell assays were used to detect viability, migration, and invasion, respectively, of colon cancer cells.

Results

The mRNA and protein levels of MON1B were higher in colon cancer tissues and human colon cancer cell lines (HT-29, SW480, COLO205, LoVo). Cell proliferation, migration, and invasion abilities were all inhibited when MON1B was silenced in LoVo colon cancer cells. Both the mRNA and protein levels of tissue inhibitor of metalloproteinase (TIMP)-2 and iκB were increased, while that of matrix metalloproteinases (MMP)-2, MMP-9, metastasis-associated genes (MTA)-1, nuclear factor-kappa B (NF-κB), and chemokine receptor type (CXCR)-4 was decreased when MON1B was silenced.

Conclusions

MON1B interference exerted anti-tumor effect in colon cancer in vitro.

Potential role of LINC00996 in colorectal cancer: a study based on data mining and bioinformatics

Background

The clinical significance of LINC00996 in colorectal cancer (CRC) has not been verified. In the current study, the authors aimed to explore the expression of LINC00996 and its clinical significance in CRC based on the data mining of Gene Expression Omnibus (GEO) and the Cancer Genome Atlas (TCGA) datasets, as well as to elucidate the functions of its potential target genes.

Materials and methods

GEO and TCGA microarray datasets were used to evaluate the LINC00996 expression and its clinical significance in CRC. LINC00996 related genes were identified by Multi Experiment Matrix, RNA-Binding Protein DataBase, and The Atlas of Noncoding RNAs in Cancer. Subsequently, they were sent to gene ontology enrichment and Kyoto Encyclopedia of Genes and Genomes pathway analysis.

Results

LINC00996 is significantly decreased in CRC tissues compared with non-tumor tissues. Low level of LINC00996 is associated with remote metastasis and poor overall survival. However, LINC00996 has a minimal effect on gender, lymphatic invasion, tumor size, lymph node metastasis, and pathological stage. One hundred and forty-two LINC00996 related genes were identified; the results of functional analysis indicated that LINC00996 might repress tumorigenesis and metastasis via modulating the JAK-STAT, NF-κB, HIF-1, TLR, and PI3K-AKT signaling pathways.

Conclusion

Our study demonstrates that decreased LINC00996 expression may be involved in colorectal carcinogenesis and metastasis, and the depletion of LINC00996 is associated with a poor outcome in CRC patients. Moreover, the JAK-STAT, NF-κB, HIF-1, TLR, and PI3K-AKT pathways may be the key pathways regulated by LINC00996 in CRC.