Hypoxic inactivation of glycogen synthase kinase-3β promotes gastric tumor growth and angiogenesis by facilitating hypoxia-inducible factor-1 signaling

Transforming growth factor-β signalling in tumour resistance to the anti-PD-(L)1 therapy: Updated

Low frequency of durable responses in patients treated with immune checkpoint inhibitors (ICIs) demands for taking complementary strategies in order to boost immune responses against cancer. Transforming growth factor-β (TGF-β) is a multi-tasking cytokine that is frequently expressed in tumours and acts as a critical promoter of tumour hallmarks. TGF-β promotes an immunosuppressive tumour microenvironment (TME) and defines a bypass mechanism to the ICI therapy. A number of cells within the stroma of tumour are influenced from TGF-β activity. There is also evidence of a relation between TGF-β with programmed death-ligand 1 (PD-L1) expression within TME, and it influences the efficacy of anti-programmed death-1 receptor (PD-1) or anti-PD-L1 therapy. Combination of TGF-β inhibitors with anti-PD(L)1 has come to the promising outcomes, and clinical trials are under way in order to use agents with bifunctional capacity and fusion proteins for bonding TGF-β traps with anti-PD-L1 antibodies aiming at reinvigorating immune responses and promoting persistent responses against advanced stage cancers, especially tumours with immunologically cold ecosystem.

Integrated proteome and phosphoproteome analysis of gastric adenocarcinoma reveals molecular signatures capable of stratifying patient outcome

Metastasis is one of the main causes of low survival rate of gastric cancer patients. Exploring key proteins in the progression of gastric adenocarcinoma (GAC) may provide new candidates for prognostic biomarker development and therapeutic intervention. We applied quantitative mass spectrometry to compare the proteome and phosphoproteome of primary tumor tissues between GAC patients with and without lymph node metastasis (LNM). We then performed an integrated analysis of the proteomic and transcriptomic data to reveal the molecular features. We quantified a total of 5536 proteins, and we found 218 upregulated and 49 downregulated proteins in tumor samples from patients with LNM compared to those without LNM. Clustering analysis identified a number of hub proteins that have been previously shown to play important roles in gastric cancer progression. We also found that two extracellular proteins, TNXB and SPON1, are overexpressed in patients with LNM, which correlates with poor survival of GAC patients. Overexpression of TNXB and SPON1 was validated by western blotting and immunohistochemistry. Furthermore, treating gastric cancer cells with anti-TNXB antibody significantly reduced cell migration. Finally, quantitative phosphoproteomic analysis combined with activity-based kinase capture revealed a number of activated kinases in primary tumor tissues from patients with LNM, among which GSK3 might be a new target that warrants further study. Our study provides a snapshot of the proteome and phosphoproteome of GAC tumor tissues that have metastatic potential, and identifies potential biomarkers for GAC progression.

Inhibition of the glycogen synthase kinase 3β-hypoxia-inducible factor 1α pathway alleviates NLRP3-mediated pyroptosis induced by high glucose in renal tubular epithelial cells

NEW FINDINGS

What is the central question of this study? Activation of the glycogen synthase kinase 3 β (GSK-3β)-hypoxia-inducible factor 1 α (HIF-1α) pathway results in stimulation of pyroptosis under high glucose, and exerts actions in a number renal diseases: does this pathway have a role in renal tubular epithelial cells? What is the main finding and its importance? Down-regulation of GSK-3β can inhibit pyroptosis of renal tubular epithelial cells induced by high glucose and this may be related to down-regulation of HIF-1α. This role of the GSK-3β-HIF-1α pathway has not previously been reported and identifies a potential new therapeutic target in diabetic nephropathy.

ABSTRACT

Diabetic nephropathy (DN) is not only one of the main complications of diabetes, but also has a high incidence rate and a high mortality rate. Glycogen synthase kinase 3 β (GSK-3β) and hypoxia-inducible factor 1 α (HIF-1α) have been demonstrated to influence DN by regulating pyroptosis. This study aimed to investigate the effect of the GSK-3β-HIF-1α pathway on pyroptosis of high-glucose (HG)-induced renal tubular cells. Mouse renal proximal tubular epithelial cells (TKPT cells) were induced by HG to simulate DN cell and we transfected TKPT cells with GSK-3β knockdown lentivirus. Western blot analysis confirmed the transfection effects and detected the expression of GSK-3β, HIF-1α, Nod-like receptor protein 3 (NLRP3), cleaved-caspase-1, pro-caspase-1, gasdermin D (GSDMD) and GSDMD-N. The expression of GSDMD-N and HIF-1α were also verified by immunofluorescence. The levels of interleukin (IL)-1β and IL-18 were measured by enzyme linked immunosorbent assay. Flow cytometric analysis determined the apoptosis rate. Results showed that HIF-1α expression was increased in HG-induced TKPT cells, and GSK-3β knockdown could decrease the levels of NLRP3, cleaved-caspase-1, GSDMD-N and HIF-1α, verified by immunofluorescence. Moreover, GSK-3β knockdown suppressed the expression of IL-1β and IL-18, and reduced the apoptosis rate. Lithium chloride (LiCl) interference could cause the same changes as GSK-3β knockdown for HG-induced TKPT cells, and dimethyloxallyl glycine could reverse the effect of GSK-3β-knockdown interference. Our studies definitively demonstrate that the GSK-3β-HIF-1α signalling pathway mediates HG-stimulated pyroptosis in renal tubular epithelial cells and that down-regulation of GSK-3β inhibited HG-induced pyroptosis by inhibiting the expression of HIF-1α. These findings suggest a new potential target for the treatment of DN.

Marsdenia tenacissima (Roxb.) Moon injection exerts a potential anti-tumor effect in prostate cancer through inhibiting ErbB2-GSK3β-HIF1α signaling axis

ETHNOPHARMACOLOGICAL RELEVANCE

Marsdenia tenacissima injection (MTE), a traditional Chinese medical injection extracted from the rattan of Marsdenia tenacissima (Roxb.) Moon, has been approved for clinical use in China as an adjuvant therapeutic agent in multiple cancers, including esophageal cancer, gastric cancer, lung cancer, and liver cancer. However, the activity and mechanism of MTE on prostate cancer (PCa) remain to be defined.

AIM OF THE STUDY

To investigate the activity and the underlying mechanism of MTE in the treatment of PCa.

MATERIALS AND METHODS

The component characterization of MTE was analyzed by HPLC-CAD-QTOF-MS/MS technology. Cell Counting Kit-8 (CCK-8) assay was used to assess PCa cell proliferation. Colony formation assay was applied to detect the clonogenic ability of the cells. MetaboAnalyst5.0 database was employed to analyze the altered metabolites of PC3 cells treated with MTE obtained by UPLC-QTOF-MS/MS. Combined with metabolomics analysis and network pharmacology, we predicted the potential targets, which further were verified by Western Blot, RT-qPCR, and Immunohistochemistry assays. Finally, SeeSAR software was applied to predict the potential active components of MTE against PCa.

RESULTS

A total of 21 components in MTE were confirmed by HPLC-CAD-QTOF-MS/MS analysis. MTE inhibited the proliferation and colony formation of PCa cells. A total of 20 metabolites closely related to glycerophospholipid metabolism, glycolysis/gluconeogenesis, and tricarboxylic acid (TCA) cycle were significantly changed in PC3 cells treated with MTE. The network pharmacology analysis revealed that MTE suppressed the growth of PC3 cells might by regulating the ErbB2-GSK3β-HIF1α signaling axis. Furthermore, we also confirmed that stimulation of MTE significantly inhibited the phosphorylation of ErbB2 at Tyr877 and the activities of its downstream signal transducers (GSK3β and HIF1α) in PCa, as well as the mRNA levels of critical factors (IDH2, LDHA, and HIF1A) in the tricarboxylic acid (TCA) cycle. Molecular docking further suggested that Tenacissimoside E, cryptochlorogenic acid, and scopoletin might be the active ingredients of MTE for PCa treatment.

CONCLUSION

This study proposed that MTE exerts a potential anti-tumor effect in PCa through inhibiting ErbB2-GSK3β-HIF1α signaling axis, which may be related to the TCA cycle.

HIF in Gastric Cancer: Regulation and Therapeutic Target

HIF means hypoxia-inducible factor gene family, and it could regulate various biological processes, including tumor development. In 2021, the FDA approved the new drug Welireg for targeting HIF-2a, and it is mainly used to treat von Hippel-Lindau syndrome, which demonstrated its good prospects in tumor therapy. As the fourth deadliest cancer worldwide, gastric cancer endangers the health of people all across the world. Currently, there are various treatment methods for patients with gastric cancer, but the five-year survival rate of patients with advanced gastric cancer is still not high. Therefore, here we reviewed the regulatory role and target role of HIF in gastric cancer, and provided some references for the treatment of gastric cancer.

Knockdown of m6A Reader IGF2BP3 Inhibited Hypoxia-Induced Cell Migration and Angiogenesis by Regulating Hypoxia Inducible Factor-1α in Stomach Cancer

Hypoxia is a common feature of solid tumors including stomach cancer (SC) and is closely associated with cancer malignant progression. N6-methyladenosine (m6A), a common modification on RNA, is involved in the regulation of RNA fate and hypoxic responses in cancers. However, the interaction between m6A reader insulin-like growth factor-II mRNA-binding protein 3 (IGF2BP3) and SC hypoxic microenvironment is poorly defined. In the present study, expression levels of IGF2BP3 and hypoxia inducible factor-1α (HIF1A) were examined by bioinformatics analysis and RT-qPCR and western blot assays. Cell migratory ability was assessed through Transwell and wound healing assays. The angiogenic potential was evaluated by VEGF secretion, tube formation, and chick embryo chorioallantoic membrane (CAM) assays. The interaction between IGF2BP3 and HIF1A was explored using bioinformatics analysis and RIP and luciferase reporter assays. The results showed that IGF2BP3 and HIF1A were highly expressed in SC tissues and hypoxia-treated SC cells. IGF2BP3 knockdown inhibited hypoxia-induced cell migration and angiogenesis in SC. IGF2BP3 positively regulated HIF1A expression by directly binding to a specific m6A site in the coding region of HIF1A mRNA in SC cells. HIF1A overexpression abrogated the effects of IGF2BP3 knockdown on hypoxia-induced cell migration and angiogenesis in SC. In conclusion, IGF2BP3 knockdown inhibited hypoxia-induced cell migration and angiogenesis by down-regulating HIF1A in SC.

Histone deacetylase inhibitor induced pVHL-independent degradation of HIF-1α and hierarchical quality control of pVHL via chaperone system

The mortality rate of ovarian cancer is increasing and the role of hypoxia inducible factor-1α (HIF-1α) in tumor progression has been confirmed. von Hippel-Lindau tumor suppressor protein (pVHL) binds HIF-1α and mediates proteasome degradation of HIF-1α. Besides, histone deacetylase inhibitor (HDACi) mitigates tumor growth via targeting HIF-1α, whereas underlying mechanism still requires investigation. In this research, we exposed ovarian cancer cell lines OV-90 and SKOV-3 to escalating concentrations of HDACi LBH589. As a result, cell viability was significantly suppressed and expression of HIF-1α was remarkably reduced along with decreased levels of signal molecules, including phosphoinositide 3-kinase (PI3K) and glycogen synthase kinase 3β (GSK3β) (P = 0.000). Interestingly, pVHL was expressed in a notably declining tendency (P = 0.000). Chaperone heat shock protein-70 (HSP70) was expressed in an ascending manner, whereas expression of chaperonin TCP-1α was reduced clearly (P = 0.000). Besides, co-inhibition of pVHL plus HDAC did not contribute to a remarkable difference in HIF-1α expression as compared with single HDAC inhibition. Furthermore, both cell lines were transfected with plasmids of VHL plus VHL binding protein-1 (VBP-1). Consequently, the expression of HIF-1α as well as lactate dehydrogenase-A (LDHA) was remarkably decreased (P = 0.000). These findings indicate HDACi may repress expression of HIF-1α via inhibiting PI3K and GSK3β and promote degradation of HIF-1α via HSP70, independent of pVHL. Additionally, a sophisticated network of HDAC and chaperones may involve in pVHL quality control.

Inhibition of the hypoxia-induced factor-1α and vascular endothelial growth factor expression through ginsenoside Rg3 in human gastric cancer cells

Objective

The aim of this study is to probe in the inhibitory effects of ginsenoside Rg3 on the expression of hypoxia-induced factor-1α (HIF-1α) and vascular endothelial growth factor (VEGF) in human gastric cancer cells.

Materials and Methods

Human gastric cancer BGC823 cells were divided into the control group and experiment group, and expression levels of HIF-1α and VEGF were detected by immunocytochemistry and Western blot after cells were cultured under hypoxia for different durations.

Results

Under hypoxia, expression of HIF-1α and VEGF in human gastric cancer BGC823 cells showed an increasing trend, and that was remarkably lower in experiment group than in the control group after applying Rg3, which was obvious at 12 and 24 h (P < 0.05).

Conclusion

Rg3 can inhibit expression of HIF-1α and VEGF in human gastric cancer cells and may influence abdominal implantation metastasis of gastric cancer through inhibiting its expression.

GSK-3 Inhibitors and Tooth Repair: An Ethical Analysis

Tideglusib^®, a GSK-3 inhibitor, was initially tested for the treatment of Alzheimer’s disease. However, a recent report has suggested its potential off-label use for the treatment of dental cavities. Even if this effect is not yet confirmed, this off-label use can have significant public/dental health consequences, mainly because of the large number of patients with cavities. The purpose of this mini-review is to perform an ethical analysis of the use of Tideglusib in dentistry. The ethical analysis identified three main areas in which ethical breaches could be significant: 1) respect for the autonomy of the patient, 2) issues raised by horizontal shifts in the translational research process, and 3) the conflict between dental beneficence and general non-maleficence. In conclusion, the use of Tideglusib in dentistry should respect the same strict ethical and regulatory criteria from clinical medicine. A translation of the potential risks should be done only after large-scale, phase-III/IV clinical trials, explicitly designed to test the usefulness of this drug in dental medicine.

New frontiers in the treatment of colorectal cancer: Autophagy and the unfolded protein response as promising targets

Colorectal cancer (CRC), despite numerous therapeutic and screening attempts, still remains a major life-threatening malignancy. CRC etiology entails both genetic and environmental factors. Macroautophagy/autophagy and the unfolded protein response (UPR) are fundamental mechanisms involved in the regulation of cellular responses to environmental and genetic stresses. Both pathways are interconnected and regulate cellular responses to apoptotic stimuli. In this review, we address the epidemiology and risk factors of CRC, including genetic mutations leading to the occurrence of the disease. Next, we discuss mutations of genes related to autophagy and the UPR in CRC. Then, we discuss how autophagy and the UPR are involved in the regulation of CRC and how they associate with obesity and inflammatory responses in CRC. Finally, we provide perspectives for the modulation of autophagy and the UPR as new therapeutic options for CRC treatment.