MESP2 binds competitively to TCF4 to suppress gastric cancer progression by regulating the SKP2/p27 axis

NONO regulates m5C modification and alternative splicing of PTEN mRNAs to drive gastric cancer progression

BACKGROUND

The effect of m5C modification on oncogene mRNAs has been well studied, while little is known about its influence on mRNAs of tumor suppressor genes (TSGs). Early studies showed PTEN, a key TSG, undergoes alternative splicing (AS) in cancers, however, the underlying regulatory mechanism remains elusive.

METHODS

We analyzed tissue microarrays and transcriptomic data derived from gastric cancer, with an emphasis on RNA splicing and m5C regulators. To unravel the role of NONO in GC, we employed RNA sequencing, RNA-Bis-Seq, RNA immunoprecipitation, RNA in situ hybridization, and Minigene reporter assay with NONO knockdown cells. The clinical relevance was validated using CDX models and human tissue microarrays.

RESULTS

Analysis of publicly available datasets and immunohistochemistry assay of tissue microarrays containing 40 GC tissues showed NONO was upregulated in GC and contributed to poor prognosis. In vitro and in vivo experiments indicated a positive regulatory role of NONO in terms of cell proliferation, migration, and invasion of GC. Mechanically, NONO interacted directly with PTEN pre-mRNA and recruited the RNA m5C methyltransferase NSUN2 via RNA-recognition motif (RRM) domains, altering the mRNA methylation pattern across PTEN pre-mRNA. The oncogenic role of NONO/NSUN2/PTEN axis in GC progression was further confirmed with pre-clinical experiments and clinical data.

CONCLUSION

Here, we revealed NONO-regulated AS of PTEN mRNA in an m5C-dependent manner, resulting in the downregulation of PTEN expression in gastric cancer (GC).This study unveils a novel regulatory mechanism of tumor suppressor gene inactivation mediated by m5C modification and related alternative splicing in cancer.

Implication of protein post translational modifications in gastric cancer

Gastric cancer (GC) is one of the most common and highly lethal malignant tumors worldwide, and its occurrence and development are regulated by multiple molecular mechanisms. Post-translational modifications (PTM) common forms include ubiquitylation, phosphorylation, acetylation and methylation. Emerging research has highlighted lactylation and glycosylation. The diverse realm of PTM and PTM crosstalk is linked to many critical signaling events involved in neoplastic transformation, carcinogenesis and metastasis. This review provides a comprehensive overview of the impact of PTM on the occurrence and progression of GC. Specifically, aberrant PTM have been shown to alter the proliferation, migration, and invasion capabilities of GC cells. Moreover, PTM are closely associated with resistance to chemotherapeutic agents in GC. Notably, this review also discusses the phenomenon of PTM crosstalk, highlighting the interactions among PTM and their roles in regulating signaling pathways and protein functions. Therefore, in-depth investigation into the mechanisms of PTM and the development of targeted therapeutic strategies hold promise for advancing early diagnosis, treatment, and prognostic evaluation of GC, offering novel insights and future research directions.

TCF4 as a potential prognostic biomarker and an anticancer target in gastric cancer

Background

Lymphoid enhancer-binding factor 1 (LEF1)/T cell factor (TCF) family members are key transcription factors in malignant tumors. In this study, the role of T cell factor 4 (TCF4) in the progression of gastric cancer (GC) cell migration and invasion was investigated.

Methods

Fifty-five pairs of GC tissues and adjacent non-tumor tissues were collected for evaluating the expression of LEF1/TCF family members, which were also evaluated by the Gene Expression Profiling Interactive Analysis (GEPIA) database, an online analysis platform based on The Cancer Genome Atlas and Genotype-Tissue Expression databases.

Results

Through GEPIA online analysis and our experimental specimens, we found that TCF4 messenger RNA (mRNA) expression was significantly upregulated in GC tissues compared with normal non-tumor tissues. The findings from protein-protein interaction (PPI) analysis suggested that myocyte enhancer factor 2C (MEF2C) may function as a regulatory gene for TCF4 and play a role in the progression of GC. A significant increase in TCF4 mRNA expression was observed in the GC cell lines. Silencing of TCF4 led to significant inhibition of the proliferation, migration, and invasion of the MGC-803 and SGC-7901 cells. TdT-mediated dUTP nick end labeling (TUNEL)-positive staining cells were significantly increased after transfection with TCF4 small interfering (si)-RNA into GC cells. In addition, patients with GC with high TCF4 expression were associated with poor T stage, pathologic stages, histologic grade, overall survival, and recurrence-free survival, indicating that TCF4 may be a potential prognostic marker of GC.

Conclusions

TCF4 potentially exerts a carcinogenic role in the progression of GC. TCF4 may serve as a prognostic indicator and therapeutic target for GC.

Genetic Risk Loci and Familial Associations in Migraine: A Genome-Wide Association Study in the Han Chinese Population of Taiwan

BACKGROUND AND PURPOSE

Migraine is a condition that is often observed to run in families, but its complex genetic background remains unclear. This study aimed to identify the genetic factors influencing migraines and their potential association with the family medical history.

METHODS

We performed a comprehensive genome-wide association study of a cohort of 1,561 outpatients with migraine and 473 individuals without migraine in Taiwan, including Han Chinese individuals with or without a family history of migraine. By analyzing the detailed headache history of the patients and their relatives we aimed to isolate potential genetic markers associated with migraine while considering factors such as sex, episodic vs. chronic migraine, and the presence of aura.

RESULTS

We revealed novel genetic risk loci, including rs2287637 in DEAD-Box helicase 1 and long intergenic non-protein coding RNA 1804 and rs12055943 in engulfment and cell motility 1, that were correlated with the family history of migraine. We also found a genetic location downstream of mesoderm posterior BHLH transcription factor 2 associated with episodic migraine, whereas loci within the ubiquitin-specific peptidase 26 exonic region, dual specificity phosphatase 9 and pregnancy-upregulated non-ubiquitous CaM kinase intergenic regions, and poly (ADP-ribose) polymerase 1 and STUM were linked to chronic migraine. We additionally identified genetic regionsassociated with the presence or absence of aura. A locus between LINC02561 and urocortin 3 was predominantly observed in female patients. Moreover, three different single-nucleotide polymorphisms were associated with the family history of migraine in the control group.

CONCLUSIONS

This study has identified new genetic locations associated with migraine and its family history in a Han Chinese population, reinforcing the genetic background of migraine. The findings point to potential candidate genes that should be investigated further.

M6A methylation of FKFB3 reduced pyroptosis of gastric cancer by NLRP3

Gastric cancer is a kind of malignant tumor that seriously endangers human life and health. Its incidence rate and mortality rate are among the highest in the global malignant tumors. Therefore, this study explored the role of 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) in the progression of gastric cancer and its underlying mechanism. Patients with gastric cancer were collected, and human GC cell lines (stomach gastric carcinoma 7901, stomach gastric carcinoma 823 , human gastric carcinoma cell line 803 and adenocarcinoma gastric stomach) were used in this study. We utilized glucose consumption, cell migration, and ELISA assay kits to investigate the function of GC. To understand its mechanism, we employed quantitative PCR (qPCR), western blot, and m6A methylated RNA immunoprecipitation assay. FKFB3 protein expression levels in patients with gastric cancer were increased. The induction of PFKFB3 mRNA expression levels in patients with gastric cancer or gastric cancer cell lines. Gastric cancer patients with high PFKFB3 expression had a lower survival rate. PFKFB3 high expression possessed the probability of pathological stage, lymph node metastasis or distant metastasis in patients with gastric cancer. PFKFB3 upregulation promoted cancer progression and Warburg effect progression of gastric cancer. PFKFB3 upregulation reduced pyroptosis and suppressed nucleotidebinding domain, leucinerich repeat containing protein 3-induced pyroptosis of gastric cancer. M6A-forming enzyme methyltransferase-like 3 increased PFKFB3 stability. Taken together, the M6A-forming enzyme methyltransferase-like 3 increased PFKFB3 stability and reduced pyroptosis in the model of gastric cancer through the Warburg effect. The PFKFB3 gene represents a potential therapeutic strategy for the treatment of gastric cancer.

SKping cell cycle regulation: role of ubiquitin ligase SKP2 in hematological malignancies

SKP2 (S-phase kinase-associated protein 2) is a member of the F-box family of substrate-recognition subunits in the SCF ubiquitin-protein ligase complexes. It is associated with ubiquitin-mediated degradation in the mammalian cell cycle components and other target proteins involved in cell cycle progression, signal transduction, and transcription. Being an oncogene in solid tumors and hematological malignancies, it is frequently associated with drug resistance and poor disease outcomes. In the current review, we discussed the novel role of SKP2 in different hematological malignancies. Further, we performed a limited in-silico analysis to establish the involvement of SKP2 in a few publicly available cancer datasets. Interestingly, our study identified Skp2 expression to be altered in a cancer-specific manner. While it was found to be overexpressed in several cancer types, few cancer showed a down-regulation in SKP2. Our review provides evidence for developing novel SKP2 inhibitors in hematological malignancies. We also investigated the effect of SKP2 status on survival and disease progression. In addition, the role of miRNA and its associated families in regulating Skp2 expression was explored. Subsequently, we predicted common miRNAs against Skp2 genes by using miRNA-predication tools. Finally, we discussed current approaches and future prospective approaches to target the Skp2 gene by using different drugs and miRNA-based therapeutics applications in translational research.

Role of F-box proteins in human upper gastrointestinal tumors

Protein ubiquitination and degradation is an essential physiological process in almost all organisms. As the key participants in this process, the E3 ubiquitin ligases have been widely studied and recognized. F-box proteins, a crucial component of E3 ubiquitin ligases that regulates diverse biological functions, including cell differentiation, proliferation, migration, and apoptosis by facilitating the degradation of substrate proteins. Currently, there is an increasing focus on studying the role of F-box proteins in cancer. In this review, we present a comprehensive overview of the significant contributions of F-box proteins to the development of upper gastrointestinal tumors, highlighting their dual roles as both carcinogens and tumor suppressors. We delve into the molecular mechanisms underlying the involvement of F-box proteins in upper gastrointestinal tumors, exploring their interactions with specific substrates and their cross-talks with other key signaling pathways. Furthermore, we discuss the implications of F-box proteins in radiotherapy resistance in the upper gastrointestinal tract, emphasizing their potential as clinical therapeutic and prognostic targets. Overall, this review provides an up-to-date understanding of the intricate involvement of F-box proteins in human upper gastrointestinal tumors, offering valuable insights for the identification of prognostic markers and the development of targeted therapeutic strategies.