Pharmacological inhibition of BUB1 suppresses UCEC progression by modulating the PI3K-AKT pathway and reversing anoikis resistance and immune evasion: a multi-omics and experimental study

BUB3: a novel prognostic biomarker and therapeutic target in hepatocellular carcinoma unveiled by pan-cancer analysis and experimental validation

BUB3 is a core component of the spindle assembly checkpoint (SAC) that is indispensable for faithful chromosome segregation and mitotic progression. Although aberrant BUB3 expression has been reported in several malignancies, its comprehensive role in tumorigenesis, immune regulation, and therapeutic response across cancers remains poorly understood. This study aimed to systematically characterize the expression landscape, clinical significance, biological functions, and therapeutic relevance of BUB3 in a pan-cancer context. A comprehensive pan-cancer analysis integrating multiple public databases and bioinformatics platforms was performed to evaluate the expression pattern, diagnostic performance, prognostic value, genomic alterations, functional pathways immune infiltration characteristics, and drug sensitivity associated with BUB3. In addition, BUB3 expression in hepatocellular carcinoma (LIHC) was validated using RT-qPCR and Western blotting, and its biological functions were further investigated through in vitro experiments. BUB3 was significantly upregulated in most cancer types and exhibited strong diagnostic performance in several malignancies. Elevated BUB3 expression was associated with unfavorable clinical outcomes, especially in head and neck squamous cell carcinoma (HNSC), LIHC, and lung adenocarcinoma (LUAD). Genetic alterations in BUB3, predominantly mutations, were frequently observed in uterine corpus endometrial carcinoma (UCEC). Copy number variation (CNV) and tumor mutation burden (TMB) positively correlated with BUB3 expression in LUAD. Functional enrichment analyses suggested that BUB3-related genes are primarily involved in cell cycle regulation, proliferation, migration, and invasion pathways. Moreover, BUB3 expression was closely associated with immune cell infiltration patterns, while single-cell analyses demonstrated predominant BUB3 expression in immune populations, particularly T cells, indicating a potential role in remodeling the TIME. Importantly, elevated BUB3 expression was associated with reduced responsiveness to immunotherapy and decreased chemosensitivity, suggesting unfavorable therapeutic outcomes in patients with high BUB3 expression. Experimental validation further demonstrated increased BUB3 expression in LIHC tissues and cell lines. Functional assays revealed that BUB3 knockdown significantly inhibited colony formation, proliferation, migration, and invasion in HepG2 and Hep3B cells, supporting its oncogenic role in LIHC progression. Our findings demonstrate that BUB3 plays a critical role in tumor progression and immune regulation and possesses substantial diagnostic and prognostic value, highlighting its potential as both a biomarker for patient stratification and a promising therapeutic target across multiple cancer types.

AKR1B15 promotes hepatocarcinogenesis by activating the p53-PI3K-AKT-mTOR-E2F1 signaling pathway.

Hepatocellular carcinoma (HCC) is a leading cause of cancer mortality worldwide, with limited biomarkers available for early diagnosis and targeted therapy. AKR1B15, a lesser-studied member of the aldo-keto reductase family, shares high sequence similarity with AKR1B10, but its role in HCC remains unclear. Therefore, this study aimed to investigate the biological function of AKR1B15 in HCC and its involvement in oncogenic signaling pathways. Bioinformatic analysis of gene expression datasets and patient tissue samples was used to evaluate AKR1B15 expression and prognostic relevance. Functional assays were conducted following AKR1B15 knockdown, including CCK-8, colony formation, transwell, wound healing, flow cytometry, and xenograft models. Western blotting and immunofluorescence were employed to assess phosphorylation of key signaling molecules. AKR1B15 expression was significantly elevated in HCC tissues and associated with higher pathologic T stage and worse disease-specific survival (P < 0.05). AKR1B15 knockdown inhibited HCC cell proliferation, invasion, and migration (P < 0.01), and promoted apoptosis (P < 0.001). In vivo, AKR1B15 depletion suppressed tumor growth and reduced Ki-67 expression. Mechanistically, silencing AKR1B15 decreased phosphorylation of p53 (Ser15), PI3K (Tyr458/199), AKT (Ser473), mTOR (Ser2448), and E2F1 (S364), indicating inhibition of the p53-PI3K-AKT-mTOR-E2F1 axis. AKR1B15 promotes HCC progression and is associated with activation of the p53-PI3K-AKT-mTOR-E2F1 signaling pathway. It may serve as a novel diagnostic marker and therapeutic target in hepatocellular carcinoma.

m6A-modified lncRNA MIAT promotes anoikis resistance and peritoneal metastasis of colorectal cancer through miR-181a-5p/MCL1 signaling axis.

BACKGROUND Colorectal cancer peritoneal metastasis (CRCPM) represents a highly aggressive clinical condition associated with limited therapeutic options and poor prognosis. Anoikis resistance, a specialized form of apoptosis induced by loss of cell-matrix interactions, is essential for tumor cell survival during peritoneal dissemination. However, the molecular mechanisms underlying anoikis resistance in CRCPM remain poorly understood. METHODS Differentially expressed lncRNAs associated with CRCPM were identified using microarray analysis and validated in clinical specimens. Gain- and loss-of-function assays were performed to evaluate the biological role of MIAT in colorectal cancer (CRC) cells, patient-derived organoids, and in vivo models. RNA pull-down, luciferase reporter, and RNA immunoprecipitation (RIP) assays were conducted to investigate the ceRNA mechanism. Methylated RNA immunoprecipitation (MeRIP) and RNA stability assays were used to assess m6A modification and its regulatory effects on MIAT. RESULTS MIAT was significantly upregulated in CRCPM tissues and anoikis-resistant CRC cells and was associated with poor prognosis. Functional assays demonstrated that MIAT silencing suppressed CRC cell proliferation, migration, invasion, and anoikis resistance in vitro and inhibited tumor growth and peritoneal metastasis in vivo. Mechanistically, MIAT acted as a competing endogenous RNA by sponging miR-181a-5p, thereby upregulating the anti-apoptotic protein MCL1. Furthermore, MIAT stability was enhanced by METTL3-mediated m6A modification in an IGF2BP2-dependent manner. CONCLUSIONS These findings identify a novel m6A-MIAT/miR-181a-5p/MCL1 signaling axis that promotes anoikis resistance and peritoneal metastasis in CRC. This study provides mechanistic insights into CRCPM progression and highlights MIAT as a potential prognostic biomarker and therapeutic target.

MX1 promotes gastric cancer cell migration via inhibiting ANXA2 ubiquitination and degradation.

Gastric cancer (GC) is a globally lethal malignancy, with invasion and metastasis driving treatment failure and poor prognosis. MX dynamin like GTPase 1 (MX1) shows tumor-specific functional heterogeneity, while its expression, biological functions and molecular mechanisms in GC remain unclear. Here, we explored MX1's clinical significance and its regulatory mechanism in GC cell migration. We integrated public databases and institutional paired clinical samples for bioinformatics analysis of MX1's correlation with clinical outcomes, and verified its pro-migratory effect via Transwell and wound healing assays. Co-immunoprecipitation/mass spectrometry (Co-IP/MS), immunofluorescence and ubiquitination assays were used to identify MX1-interacting proteins and dissect the underlying mechanism, and the Genomics of Drug Sensitivity in Cancer database was applied for chemosensitivity analysis. MX1 was aberrantly upregulated in GC tissues and served as an independent prognostic biomarker, with high expression associated with shortened overall, first-progression and post-progression survival. MX1 promoted GC cell migration and epithelial-mesenchymal transition pathway enrichment, and directly bound Annexin A2 (ANXA2) in the cytoplasm; both were co-enriched in endothelial and epithelial cells by single-cell sequencing. MX1 dose-dependently upregulated ANXA2 protein (without affecting its mRNA) by inhibiting NEDD4L/TRIM65-mediated ANXA2 ubiquitination and degradation, enhancing ANXA2 stability. Additionally, high MX1 expression correlated with increased paclitaxel sensitivity in GC patients based on database analysis, and CCK-8 assays confirmed that MX1 overexpression significantly reduced the paclitaxel IC50 in gastric cancer cells, supporting its potential as a predictive biomarker for paclitaxel efficacy. This study demonstrates that MX1 promotes GC cell migration by suppressing ANXA2 ubiquitination and degradation, highlighting the critical role of the MX1-ANXA2 axis in GC progression. These findings provide novel molecular targets and theoretical support for GC prognostic evaluation, individualized chemotherapy and targeted therapy.

GATA6-mediated transcriptional activation and METTL3/IGF2BP2-dependent post-transcriptional stabilization upregulate CDC20 to promote the malignant progression of colorectal cancer and immune escape

UBTD1 Drives Ovarian Cancer Progression via Mutation‐Associated Alterations, Stromal Microenvironment Remodeling, and TNF/AP‐1 Signaling

Background The ubiquitin domain‐containing protein 1 (UBTD1) is involved in protein homeostasis and cell cycle regulation, and emerging evidence suggests its role in tumor biology. However, its function in ovarian cancer (OC) remains unclear. OC is highly lethal due to late diagnosis, metastasis, and platinum resistance. This study is aimed at investigating the role of UBTD1 in OC by integrating single‐cell transcriptomics, mutation and HRD‐related analyses, tumor microenvironment evaluation, and experimental validation. Methods We examined UBTD1 expression, prognosis, somatic mutation features, and immune microenvironment characteristics utilizing public databases, such as the Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Single‐cell RNA‐seq data were analyzed using Seurat, hdWGCNA, and CopyKAT to characterize UBTD1‐associated malignant‐cell states and inferred CNV burden. Based on the median UBTD1 expression, TCGA‐OV samples were divided into high and low expression groups to compare mutation spectra, DNA repair pathway activity, stromal scores, and immune cell infiltration. Functional assays were performed in A2780 and SK‐OV‐3 cell lines following lentiviral shRNAs‐mediated UBTD1 knockdown. RNA sequencing and rescue experiments were used to explore downstream pathways. Results Integrated single‐cell and TCGA‐OV analyses revealed that UBTD1‐low tumors were enriched for genomic instability–related features, including increased inferred CNV burden and higher tumor mutation burden. By comparison, UBTD1‐high tumors showed increased stromal scores and modest enrichment of selected immune‐cell populations, including macrophages and neutrophils. Experimentally, UBTD1 was upregulated in OC and associated with poor prognosis. UBTD1 knockdown inhibited malignant phenotypes, enhanced cisplatin sensitivity, promoted apoptosis, and suppressed TNF/AP‐1/FOS–related signaling. FOS overexpression partially reversed the effects of UBTD1 silencing. Conclusions UBTD1 expression defines distinct mutation and microenvironmental states in OC and functionally promotes malignant phenotypes, potentially through TNF/AP‐1/FOS–related signaling.