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

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.