The HIF-1α as a Potent Inducer of the Hallmarks in Gastric Cancer

Integrative pharmacological analysis of modified Zuojin formula: Inhibiting the HIF-1α-mediated glycolytic pathway in chronic atrophic gastritis

ETHNOPHARMACOLOGICAL RELEVANCE

Zuojin formula (ZJF) is a well-known herbal medicine in Pharmacopoeia of China, which is widely used for gastritis. Modified Zuojin formula (MZJF) was adapted based on traditional Chinese medicine (TCM) theories concerning gastric atrophy and dysplasia, along with extensive clinical experience, has been clinically employed to treat chronic atrophic gastritis (CAG). However, the underlying mechanisms by which MZJF intervenes in CAG remain to be fully elucidated.

AIM OF THE STUDY

The aim of this study was to evaluate the effects of MZJF intervention in CAG and explore its potential mechanisms.

METHODS

Four induction factors were used to establish a CAG rat model. HE and AB-PAS staining was utilized to assess the effects of MZJF in the intervention of CAG. The stomach weight index and gastric acid pH was used to assess the overall state of stomach. ELISA was used to assess the gastric mucosal inflammatory response. Using transmission electron microscopy to observe chief cells and parietal cells, we evaluated the improvement of ultrastructure by MZJF. Through network pharmacology analysis, the possible regulatory mechanism of MZJF in CAG was preliminarily explored. Binding interactions between MZJF components and predicted targets were explored using molecular docking. Subsequently, quantitative real-time PCR (qRT-PCR), Western blot, biochemical analysis and TUNEL staining were applied to validate the effect of MZJF on predicted pathway.

RESULTS

MZJF treatment ameliorated gastric mucosal pathology, inflammation, cellular ultrastructural damage and PG levels, halted the exacerbation of CAG in rats, along with a reduction in stomach weight index and gastric acid pH. A total of 79 compounds in MZJF targeting 203 CAG-related molecules were identified through network pharmacology. Enrichment analysis of the core targets was focused on the hypoxia inducible factor-1α (HIF-1α) signaling pathway. Molecular docking results identified HIF-1α as stable binding targets for MZJF primary components. Subsequently, PCR, WB, and biochemical results showed that MZJF suppressed the gene and protein expression levels of HIF-1α and its downstream molecules including glycolytic enzymes and transporters, modulated glucose, pyruvic acid and lactate levels in gastric mucosal tissue. Moreover, MZJF induced apoptosis of gastric epithelial cells, as evidenced by the upregulation of cleaved caspase-3, Bax, Bax/Bcl-2 and TUNEL positive cells ratio.

CONCLUSIONS

MZJF suppressed the HIF-1α-mediated glycolytic pathway, and promoted cell apoptosis, thereby halting the malignant transformation of CAG. The study provides a valuable reference point for applying TCM in preventing and treating CAG.

Prediction of HIF-1α expression in endometrial carcinoma by enhanced T2 ∗ weighted angiography and dynamic contrast-enhanced magnetic resonance imaging

Purpose

To explore the value of quantitative imaging parameters by enhanced T2 * weighted angiography (ESWAN) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) for evaluating the expression of Hypoxia-inducible factor-1α (HIF-1α) in endometrial carcinoma (EC).

Methods

Data from 122 patients with EC confirmed by clinical pathology were retrospectively analyzed. According to the number of positive cells stained with HIF-1α by immunohistochemistry, patients were divided into two groups: 65 cases with high expression of HIF-1α and 57 cases with low expression of HIF-1α. Clinical data included age, FIGO stage, menopausal status, abnormal uterine bleeding, and pathological type. All patients underwent preoperative 1.5T MRI scans, including ESWAN and DCE-MRI. The amplitude, phase, and R2 * values derived from ESWAN and the volume transfer constant (Ktrans), rate constant (Kep), and extravascular volume fraction (Ve) values derived from DCE-MRI were measured by two observers, respectively. The intra-class correlation coefficient (ICC) was used to assess the measurement of reproducibility across observers, and the differences in imaging parameters between the two groups were compared using the independent sample t-test or Mann-Whitney U-test. Binary logistic regression analysis was used to find independent risk factors for HIF-1α expression. The efficacy of selected imaging parameters for predicting HIF-1α expression was assessed using receiver operating characteristic (ROC) curves, and the Delong test was used to compare the area under ROC curves (AUC).

Results

The consistency between the two observers was good (ICC>0.75). The R2 *, Ktrans, and Kep values of the HIF-1α high expression group were higher than those of the HIF-1α low expression group (14.59 ± 4.06 vs. 11.99 ± 2.84 Hz, 0.45 ± 0.18 vs. 0.36 ± 0.14/min, and 2.17 ± 1.10 vs. 1.54 ± 0.80/min) (P< 0.001, P = 0.011, and P =0.001). Binary logistic regression analysis revealed that R2 * and Kep values were independent risk factors for HIF-1α expression. The AUC values of R2 *, Kep, and their combination for prediction of HIF-1α expression were 0.697, 0.677, and 0.781, respectively. The diagnostic efficacy was significantly improved with combination of R2 * and Kep.

Conclusions

Quantitative parameters by ESWAN and DCE-MRI showed significant differences between EC patients with low and high expression of HIF-1α, and the combination of ESWAN and DCE-MRI improves the efficacy in prediction of HIF-1α expression in EC, which has an excellent clinical application prospect.

Is Chronic Ice Water Ingestion a Risk Factor for Gastric Cancer Development? An Evidence-Based Hypothesis Focusing on East Asian Populations

This article introduces a novel risk factor for gastric cancer (GC) by analyzing available epidemiological data from East Asian populations. A significantly higher age-standardized GC rate was observed in Japanese and Korean populations than in Chinese populations, despite nearly identical ethnicity, food habits, obesity rates, and alcohol consumption. Given the pivotal role of environmental factors in GC development, particularly for the intestinal type, a thorough evaluation of the lifestyles of these three populations was conducted to identify commonalities and disparities. It was observed that Japanese and Korean individuals prefer consuming ice water, while Chinese individuals tend to drink warm water, potentially influenced by traditional Chinese medicine disciplines. Considering the key features of GC development, a literature review was conducted to investigate the mechanisms through which the consumption of ice water might contribute to GC initiation and progression. Mechanistically, exposing gastric cells to hypothermia can increase the risk of carcinogenesis through multiple pathways. This includes the promotion of Helicobacter pylori colonization, prolonged gastric inflammation, and mitochondrial dysfunction in gastric cells. Furthermore, drinking ice water can enhance the survival, proliferation, and invasion of GC cells by releasing cold shock proteins, increasing gastric acid secretion, and delaying gastric emptying. Additionally, hypothermia can boost the immune evasion of cancer cells by weakening the antitumor immune system and activating different components of the tumor microenvironment. This paper also explores the association between exposure of GC cells to hypothermia and current insights into cancer hallmarks. These findings may partially elucidate the higher incidence of GC in Japanese and Korean populations and provide a clue for future experimental studies.Graphical abstract available for this article.

Modified Zuojin pill alleviates gastric precancerous lesions by inhibiting glycolysis through the HIF-1α pathway

BACKGROUND

Gastric precancerous lesions (GPL) typically originates from chronic gastritis (CG), and the changes in glycolysis mediated by the HIF-1α pathway during the progression from CG to GPL are unclear. Modified Zuojin pill (SQQT) is a traditional Chinese herbal formula used for treating GPL. However, the underlying mechanism has not been fully elucidated.

PURPOSE

To investigate the changes in glycolysis mediated by the HIF-1α pathway during the progression from CG to GPL and whether SQQT can alleviate GPL by attenuating glycolysis through the HIF-1α pathway.

METHODS

A rat model of GPL was established, and the changes of glycolysis mediated by the HIF-1α pathway during the progression from CG to GPL were detected in 12th, 18th, 24th, and 30th weeks. The therapeutic efficacy of SQQT was evaluated through pathological changes. In vitro, the GPL cell model (MC cell) originated from GES-1 cells intervened by MNNG. The effects of SQQT on glycolysis and the HIF-1α pathway were detected in vivo and in vitro. In vitro, HIF-1α overexpression was used to confirmed that SQQT attenuated glycolysis by targeting the HIF-1α pathway.

RESULTS

Our study revealed that glycolysis mediated by the HIF-1α pathway exhibited dynamic changes in the progression from CG to GPL, characterized by sequential activation, deactivation, and reactivation. SQQT ameliorated gastric mucosal pathology and inflammation in GPL rats. Mechanistic studies revealed that SQQT alleviated glycolysis by targeting the HIF-1α pathway, and improved abnormal cellular proliferation and apoptosis. Importantly, HIF-1α overexpression blocked the effect of SQQT on glycolysis.

CONCLUSION

In the progression from CG to GPL, the HIF-1α pathway-mediated glycolysis was characterized by sequential activation, deactivation, and reactivation. SQQT attenuated glycolysis by targeting the HIF-1α pathway and improved abnormal cellular proliferation and apoptosis in the gastric mucosa, thereby exerting therapeutic effects on GPL.

Targeting PGK1: A New Frontier in Breast Cancer Therapy Under Hypoxic Conditions

Breast cancer represents one of the most prevalent malignant neoplasms affecting women, and its pathogenesis has garnered significant scholarly interest. Research indicates that the progression of breast cancer is intricately regulated by glucose metabolism. Under hypoxic conditions within the tumor microenvironment, breast cancer cells generate ATP and essential biosynthetic precursors for growth via the glycolytic pathway. Notably, phosphoglycerate kinase 1 (PGK1) is intimately associated with the regulation of hypoxia-inducible factors in breast cancer and plays a crucial role in modulating glycolytic processes. Further investigation into the role of PGK1 in breast cancer pathogenesis is anticipated to identify novel therapeutic targets and strategies. This review consolidates current research on the regulation of glucose metabolism and the function of PGK1 in breast cancer within hypoxic conditions. It aims to offer a significant theoretical foundation for elucidating the mechanisms underlying breast cancer progression and metastasis, thereby facilitating the development of innovative treatment approaches.

Development and validation of a hypoxia- and mitochondrial dysfunction- related prognostic model based on integrated single-cell and bulk RNA sequencing analyses in gastric cancer

Introduction

Gastric cancer (GC) remains a major global health threat ranking as the fifth most prevalent cancer. Hypoxia, a characteristic feature of solid tumors, significantly contributes to the malignant progression of GC. Mitochondria are the major target of hypoxic injury that promotes mitochondrial dysfunction during the development of cancers including GC. However, the gene signature and prognostic model based on hypoxia- and mitochondrial dysfunction-related genes (HMDRGs) in the prediction of GC prognosis have not yet been established.

Methods

The gene expression profile datasets of stomach cancer patients were retrieved from The Cancer Genome Atlas and the Gene Expression Omnibus databases. Prognostic genes were selected using Least Absolute Shrinkage and Selection Operator Cox (LASSO-Cox) regression analysis to construct a prognostic model. Immune infiltration was evaluated through ESTIMATE, CIBERSORT, and ssGSEA analyses. Tumor immune dysfunction and exclusion (TIDE) and immunophenoscore (IPS) were utilized to explore implications for immunotherapy. Furthermore, in vitro experiments were conducted to validate the functional roles of HMDRGs in GC cell malignancy.

Results

In this study, five HMDRGs (ZFP36, SERPINE1, DUSP1, CAV1, and AKAP12) were identified for developing a prognostic model in GC. This model stratifies GC patients into high- and low-risk groups based on median risk scores. A nomogram predicting overall survival (OS) was constructed and showed consistent results with observed OS. Immune infiltration analysis indicated that individuals in the high-risk group tend to exhibit increased immune cell infiltration. Additionally, analysis of cancer immunotherapy responses revealed that high-risk group patients exhibit poorer responses to cancer immunotherapy compared to the low-risk group. Immunohistochemistry (IHC) staining indicated that the expression levels of HMDRGs were remarkably correlated with GC, of which, SERPINE1 displayed the most pronounced up-regulation, while ZFP36 exhibited the most notable down-regulation in GC patients. Furthermore, in vitro investigation validated that SERPINE1 and ZFP36 contribute to the malignant processes of GC cells correlated with mitochondrial dysfunction.

Conclusions

This study presents a novel and efficient approach to evaluate GC prognosis and immunotherapy efficacy, and also provides insights into understanding the pathogenesis of GC.

Targeting vascular disrupting agent-treated tumor microenvironment with tissue-penetrating nanotherapy

Cancer treatment with vascular disrupting agents (VDAs) causes rapid and extensive necrosis in solid tumors. However, these agents fall short in eliminating all malignant cells, ultimately leading to tumor regrowth. Here, we investigated whether the molecular changes in the tumor microenvironment induced by VDA treatment sensitize the tumors for secondary nanotherapy enhanced by clinical-stage tumor penetrating peptide iRGD. Treatment of peritoneal carcinomatosis (PC) and breast cancer mice with VDA combretastatin A-4 phosphate (CA4P) resulted in upregulation of the iRGD receptors αv-integrins and NRP-1, particularly in the peripheral tumor tissue. In PC mice treated with CA4P, coadministration of iRGD resulted in an approximately threefold increase in tumor accumulation and a more homogenous distribution of intraperitoneally administered nanoparticles. Notably, treatment with a combination of CA4P, iRGD, and polymersomes loaded with a novel anthracycline Utorubicin (UTO-PS) resulted in a significant decrease in the overall tumor burden in PC-bearing mice, while avoiding overt toxicities. Our results indicate that VDA-treated tumors can be targeted therapeutically using iRGD-potentiated nanotherapy and warrant further studies on the sequential targeting of VDA-induced molecular signatures.

Adjuvant Properties of Caffeic Acid in Cancer Treatment

Caffeic acid (CA) is a polyphenol belonging to the phenylpropanoid family, commonly found in plants and vegetables. It was first identified by Hlasiwetz in 1867 as a breakdown product of caffetannic acid. CA is biosynthesized from the amino acids tyrosine or phenylalanine through specific enzyme-catalyzed reactions. Extensive research since its discovery has revealed various health benefits associated with CA, including its antioxidant, anti-inflammatory, and anticancer properties. These effects are attributed to its ability to modulate several pathways, such as inhibiting NFkB, STAT3, and ERK1/2, thereby reducing inflammatory responses, and activating the Nrf2/ARE pathway to enhance antioxidant cell defenses. The consumption of CA has been linked to a reduced risk of certain cancers, mitigation of chemotherapy and radiotherapy-induced toxicity, and reversal of resistance to first-line chemotherapeutic agents. This suggests that CA could serve as a useful adjunct in cancer treatment. Studies have shown CA to be generally safe, with few adverse effects (such as back pain and headaches) reported. This review collates the latest information from Google Scholar, PubMed, the Phenol-Explorer database, and ClinicalTrials.gov, incorporating a total of 154 articles, to underscore the potential of CA in cancer prevention and overcoming chemoresistance.

YTHDF2 promotes gastric cancer progression and enhances chemoradiotherapy resistance

The role of YTHDF2 in gastric cancer (GC) is controversial. Due to the limitations of technical difficulty and experimental period, research on completely knocking out YTHDF2 is rare. Therefore, further investigations are still needed to clarify the YTHDF2's clinical significance and biological function in GC. To carry out the investigation, an analysis was performed on the expression levels of YTHDF2 in both publicly available databases and samples obtained from patients with gastric cancer. Based on the complete knockout of YTHDF2 using the CRISPR-Cas9 system, in vivo and in vitro experiments were conducted to analyze the effects of YTHDF2 on tumor formation, radiotherapy and chemoradiotherapy resistance in GC. Our investigation revealed an increase in YTHDF2 levels in GC tissues, which was found to be associated with a negative prognosis. Under hypoxic conditions, high expression of YTHDF2 enhanced the invasion of gastric cancer cells, and high expression of YTHDF2 was associated with HIF-1a. YTHDF2 facilitated gastric cancer cell growth in vitro and in vivo. Moreover, the results of the present study demonstrated that YTHDF2 mediated the expression of CyclinD1 and stability of CyclinD1 mRNA. CyclinD1 knockdown inhibited YTHDF2-mediated GC cell proliferation whereas CyclinD1 overexpression ameliorated YTHDF2 knockdown-induced inhibition of GC progression. Furthermore, YTHDF2 also promoted resistance to DDP and CTX chemotherapy, along with radiotherapy treatment for GC cells. The findings suggested that YTHDF2 expression accelerated GC progression through a potential mechanism involving CyclinD1 expression, and enhanced chemoradiotherapy resistance. This indicated that YTHDF2 could be a promising prognostic biomarker and therapeutic target for individuals diagnosed with GC.

Cancer-associated fibroblasts: protagonists of the tumor microenvironment in gastric cancer

Enhanced knowledge of the interaction of cancer cells with their environment elucidated the critical role of tumor microenvironment in tumor progression and chemoresistance. Cancer-associated fibroblasts act as the protagonists of the tumor microenvironment, fostering the metastasis, stemness, and chemoresistance of cancer cells and attenuating the anti-cancer immune responses. Gastric cancer is one of the most aggressive cancers in the clinic, refractory to anti-cancer therapies. Growing evidence indicates that cancer-associated fibroblasts are the most prominent risk factors for a poor tumor immune microenvironment and dismal prognosis in gastric cancer. Therefore, targeting cancer-associated fibroblasts may be central to surpassing resistance to conventional chemotherapeutics, molecular-targeted agents, and immunotherapies, improving survival in gastric cancer. However, the heterogeneity in cancer-associated fibroblasts may complicate the development of cancer-associated fibroblast targeting approaches. Although single-cell sequencing studies started dissecting the heterogeneity of cancer-associated fibroblasts, the research community should still answer these questions: "What makes a cancer-associated fibroblast protumorigenic?"; "How do the intracellular signaling and the secretome of different cancer-associated fibroblast subpopulations differ from each other?"; and "Which cancer-associated fibroblast subtypes predominate specific cancer types?". Unveiling these questions can pave the way for discovering efficient cancer-associated fibroblast targeting strategies. Here, we review current knowledge and perspectives on these questions, focusing on how CAFs induce aggressiveness and therapy resistance in gastric cancer. We also review potential therapeutic approaches to prevent the development and activation of cancer-associated fibroblasts via inhibition of CAF inducers and CAF markers in cancer.

Network pharmacology and experimental evaluation strategies to decipher the underlying pharmacological mechanism of Traditional Chinese Medicine CFF-1 against prostate cancer

Prostate cancer (PCa) is a common malignancy in elderly men. We have applied Traditional Chinese Medicine CFF-1 in clinical treatments for PCa for several years. Here, we aimed to identify the underlying mechanism of CFF-1 on PCa using network pharmacology and experimental validation. Active ingredients, potential targets of CFF-1 were acquired from the public databases. Subsequently, protein-protein interaction (PPI) and the herbs-active ingredients-target network was constructed. A prognostic model for PCa was also constructed based on key targets. In vitro experiments using PCa cell lines CWR22Rv1 and PC-3 were carried out to validate the potential mechanism of CFF-1 on PCa. A total of 112 bioactive compounds and 359 key targets were screened from public databases. PPI and herbs-active ingredients-target network analysis determined 12 genes as the main targets of CFF-1 on PCa. Molecular docking studies indicated that the primary active ingredients of CFF-1 possess strong binding affinity to the top five hub targets. DNMT3B, RXRB and HPRT1 were found to be involved in immune regulation of PCa. In vitro, CFF-1 was found to inhibit PCa cell proliferation, migration, invasion and induce apoptosis via PI3K-Akt, HIF-1, TNF, EGFR-TKI resistance and PD-1 checkpoint signaling pathways. This study comprehensively elucidates the underlying molecular mechanism of CFF-1 against PCa, offering a strong rationale for clinical application of CFF-1 in PCa treatment.

HPV16 E6 Oncogene Contributes to Cancer Immune Evasion by Regulating PD-L1 Expression through a miR-143/HIF-1a Pathway

Human Papillomaviruses have been associated with the occurrence of cervical cancer, the fourth most common cancer that affects women globally, while 70% of cases are caused by infection with the high-risk types HPV16 and HPV18. The integration of these viruses' oncogenes E6 and E7 into the host's genome affects a multitude of cellular functions and alters the expression of molecules. The aim of this study was to investigate how these oncogenes contribute to the expression of immune system control molecules, using cell lines with integrated HPV16 genome, before and after knocking out E6 viral gene using the CRISPR/Cas9 system, delivered with a lentiviral vector. The molecules studied are the T-cell inactivating protein PD-L1, its transcription factor HIF-1a and the latter's negative regulator, miR-143. According to our results, in the E6 knock out (E6KO) cell lines an increased expression of miR-143 was recorded, while a decrease in the expression of HIF-1a and PD-L1 was exhibited. These findings indicate that E6 protein probably plays a significant role in enabling cervical cancer cells to evade the immune system, while we propose a molecular pathway in cervical cancer, where PD-L1's expression is regulated by E6 protein through a miR-143/HIF-1a axis.

IDF-11774 Induces Cell Cycle Arrest and Apoptosis by Inhibiting HIF-1α in Gastric Cancer

Hypoxia-inducible factor-1 alpha (HIF-1α) is a regulatory factor of intracellular oxygen supersession. The expression or increased activity of HIF-1α is closely related to various human cancers. Previously, IDF-11774 was demonstrated to inhibit HSP70 chaperone activity and suppress the accumulation of HIF-1α. In this study, we aimed to determine the effects of IDF-11774 on gastric cancer cell lines. Treatment with IDF-11774 was found to markedly decrease the proliferation, migration, and invasion of the gastric cancer cell lines. Furthermore, the phosphorylation levels of extracellular signal-regulated kinase 1/2, p38, and Jun N-terminal kinase in the mitogen-activated protein kinase signaling pathways were markedly increased in a dose-dependent manner, ultimately promoting apoptosis via the induction of cell cycle arrest. Our findings indicate that HIF-1α inhibitors are potent drugs for the treatment of gastric cancer.

Biological function, regulatory mechanism, and clinical application of mannose in cancer

Studies examining the regulatory roles and clinical applications of monosaccharides other than glucose in cancer have been neglected. Mannose, a common type of monosaccharide found in human body fluids and tissues, primarily functions in protein glycosylation rather than carbohydrate metabolism. Recent research has demonstrated direct anticancer effects of mannose in vitro and in vivo. Simply supplementing cell culture medium or drinking water with mannose achieved these effects. Moreover, mannose enhances the effectiveness of current cancer treatments including chemotherapy, radiotherapy, targeted therapy, and immune therapy. Besides the advancements in basic research on the anticancer effects of mannose, recent studies have reported its application as a biomarker for cancer or in the delivery of anticancer drugs using mannose-modified drug delivery systems. This review discusses the progress made in understanding the regulatory roles of mannose in cancer progression, the mechanisms underlying its anticancer effects, and its current application in cancer diagnosis and treatment.

Molecular mechanism of oroxyli semen against triple-negative breast cancer verified by bioinformatics and in vitro experiments

OBJECTIVE

This study aimed to use network pharmacology to predict the therapeutic mechanism of oroxyli semen (OS) on triple-negative breast cancer (TNBC) and validate it through in vitro experiments.

METHODS

The active ingredients and target proteins of OS were retrieved from the Traditional Chinese Medicine Systems Pharmacology database, and the TNBC-related target genes were obtained from the GeneCards database. The overlapping genes were used to construct a protein-protein interaction (PPI) network via the String database. Furthermore, we employed an online bioinformatics analysis platform (https://www.bioinformatics.com.cn/) to perform gene ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses to evaluate biological processes, molecular functions, and cellular components and generate simulated signal pathways. Additionally, molecular docking was used to evaluate the binding ability of small molecule drugs and signaling pathway targets. CCK8 assay was conducted to detect the effect of small molecule drugs on TNBC cell viability, and Western Blot was utilized to verify the expression of AKT, VEGF, and hypoxia-inducible factor 1-alpha (HIF-1α) proteins.

RESULTS

Fifteen active ingredients and 166 therapeutic targets of OS were obtained from the Traditional Chinese Medicine Systems Pharmacology database. The Venn diagram revealed that 163 targets were related to TNBC. The protein-protein interaction network analysis identified AKT1, IL-6, JUN, vascular endothelial growth factor A (VEGFA), CASP3, and HIF-1α as potential core targets through which OS may treat TNBC. Furthermore, the molecular docking results indicated that the active ingredient chryseriol in OS had good binding ability with VEGFA, and HIF-1α. CCK8 assay results indicated that chryseriol inhibited the viability of MDA-MB-231 and BT-20 cells. Western Blot demonstrated that chryseriol intervention led to a decrease in VEGFA, and HIF-1α protein expression compared with the control group (P < .05), increased the cleaved PARP.

CONCLUSION

OS may exert its therapeutic effects on TNBC through multiple cellular signaling pathways. Chryseriol, the active component of OS, can enhance the apoptosis of TNBC cells by targeting VEGFA/HIF-1α pathway. This study provided new insights into the potential therapeutic mechanism of OS for TNBC and may aid in the development of novel therapeutic approaches for TNBC.

Construction of a hypoxia-immune-related prognostic panel based on integrated single-cell and bulk RNA sequencing analyses in gastric cancer

Introduction

Gastric cancer (GC) is the fifth most common tumor, contributing to the third-highest number of cancer-related deaths. Hypoxia is a major feature of the tumor microenvironment. This study aimed to explore the influence of hypoxia in GC and establish a hypoxia-related prognostic panel.

Methods

The GC scRNA-seq data and bulk RNA-seq data were downloaded from the GEO and TCGA databases, respectively. AddModuleScore() and AUCell() were used to calculate module scores and fractions of enrichment for hypoxia-related gene expression in single cells. Least absolute shrinkage and selection operator cox (LASSO-COX) regression analysis was utilized to build a prognostic panel, and hub RNAs were validated by qPCR. The CIBERSORT algorithm was adopted to evaluate immune infiltration. The finding of immune infiltration was validated by a dual immunohistochemistry staining. The TIDE score, TIS score and ESTIMATE were used to evaluate the immunotherapy predictive efficacy.

Results

Hypoxia-related scores were the highest in fibroblasts, and 166 differentially expressed genes were identified. Five hypoxia-related genes were incorporated into the hypoxia-related prognostic panel. 4 hypoxia-related genes (including POSTN, BMP4, MXRA5 and LBH) were significantly upregulated in clinical GC samples compared with the normal group, while APOD expression decreased in GC samples. Similar results were found between cancer-associated fibroblasts (CAFs) and normal fibroblasts (NFs). A high hypoxia score was associated with advanced grade, TNM stage, N stage, and poorer prognosis. Decreased antitumor immune cells and increased cancer-promoting immune cells were found in patients with high hypoxia scores. Dual immunohistochemistry staining showed high expression of CD8 and ACTA2 in gastric cancer tissue. In addition, the high hypoxia score group possessed higher TIDE scores, indicating poor immunotherapy benefit. A high hypoxia score was also firmly related to sensitivity to chemotherapeutic drugs.

Discussion

This hypoxia-related prognostic panel may be effective in predicting the clinical prognosis, immune infiltrations, immunotherapy, and chemotherapy in GC.

The hypoxia-inducible factor-1α in stemness and resistance to chemotherapy in gastric cancer: Future directions for therapeutic targeting

Hypoxia-inducible factor-1α (HIF-1α) is a crucial mediator of intra-tumoral heterogeneity, tumor progression, and unresponsiveness to therapy in tumors with hypoxia. Gastric tumors, one of the most aggressive tumors in the clinic, are highly enriched in hypoxic niches, and the degree of hypoxia is strongly correlated with poor survival in gastric cancer patients. Stemness and chemoresistance in gastric cancer are the two root causes of poor patient outcomes. Based on the pivotal role of HIF-1α in stemness and chemoresistance in gastric cancer, the interest in identifying critical molecular targets and strategies for surpassing the action of HIF-1α is expanding. Despite that, the understanding of HIF-1α induced signaling in gastric cancer is far from complete, and the development of efficacious HIF-1α inhibitors bears various challenges. Hence, here we review the molecular mechanisms by which HIF-1α signaling stimulates stemness and chemoresistance in gastric cancer, with the clinical efforts and challenges to translate anti-HIF-1α strategies into the clinic.