High expression of Tob1 indicates poor survival outcome and promotes tumour progression via a Wnt positive feedback loop in colon cancer

A pan-cancer analysis of anti-proliferative protein family genes for therapeutic targets in cancer

The recently discovered APRO (anti-proliferative protein) family encodes a group of trans-membrane glycoproteins and includes 6 members: TOB1, TOB2, BTG1, BTG2, BTG3 and BTG4. The APRO family is reportedly associated with the initiation and progression of cancers. This study aims to undertake a comprehensive investigation of the APRO family of proteins as a prognostic biomarker in various human tumors. We performed a pan-cancer analysis of the APRO family based on The Cancer Genome Atlas (TCGA). With the bioinformatics methods, we explored the prognostic value of the APRO family and the correlation between APRO family expression and tumor mutation burden (TMB), microsatellite instability (MSI), drug sensitivity, and immunotherapy in numerous cancers. Our results show that the APRO family was primarily down-regulated in cancer samples. The expression of APRO family members was linked with patient prognosis. In addition, APRO family genes showed significant association with immune infiltrate subtypes, tumor microenvironment, and tumor cell stemness. Finally, our study also demonstrated the relationship between APRO family genes and drug sensitivity. This study provides comprehensive information to understand the APRO family's role as an oncogene and predictor of survival in some tumor types.

Unveiling the role of regulatory T cells in the tumor microenvironment of pancreatic cancer through single-cell transcriptomics and in vitro experiments

Background

In order to investigate the impact of Treg cell infiltration on the immune response against pancreatic cancer within the tumor microenvironment (TME), and identify crucial mRNA markers associated with Treg cells in pancreatic cancer, our study aims to delve into the role of Treg cells in the anti-tumor immune response of pancreatic cancer.

Methods

The ordinary transcriptome data for this study was sourced from the GEO and TCGA databases. It was analyzed using single-cell sequencing analysis and machine learning. To assess the infiltration level of Treg cells in pancreatic cancer tissues, we employed the CIBERSORT method. The identification of genes most closely associated with Treg cells was accomplished through the implementation of weighted gene co-expression network analysis (WGCNA). Our analysis of single-cell sequencing data involved various quality control methods, followed by annotation and advanced analyses such as cell trajectory analysis and cell communication analysis to elucidate the role of Treg cells within the pancreatic cancer microenvironment. Additionally, we categorized the Treg cells into two subsets: Treg1 associated with favorable prognosis, and Treg2 associated with poor prognosis, based on the enrichment scores of the key genes. Employing the hdWGCNA method, we analyzed these two subsets to identify the critical signaling pathways governing their mutual transformation. Finally, we conducted PCR and immunofluorescence staining in vitro to validate the identified key genes.

Results

Based on the results of immune infiltration analysis, we observed significant infiltration of Treg cells in the pancreatic cancer microenvironment. Subsequently, utilizing the WGCNA and machine learning algorithms, we ultimately identified four Treg cell-related genes (TRGs), among which four genes exhibited significant correlations with the occurrence and progression of pancreatic cancer. Among them, CASP4, TOB1, and CLEC2B were associated with poorer prognosis in pancreatic cancer patients, while FYN showed a correlation with better prognosis. Notably, significant differences were found in the HIF-1 signaling pathway between Treg1 and Treg2 cells identified by the four genes. These conclusions were further validated through in vitro experiments.

Conclusion

Treg cells played a crucial role in the pancreatic cancer microenvironment, and their presence held a dual significance. Recognizing this characteristic was vital for understanding the limitations of Treg cell-targeted therapies. CASP4, FYN, TOB1, and CLEC2B exhibited close associations with infiltrating Treg cells in pancreatic cancer, suggesting their involvement in Treg cell functions. Further investigation was warranted to uncover the mechanisms underlying these associations. Notably, the HIF-1 signaling pathway emerged as a significant pathway contributing to the duality of Treg cells. Targeting this pathway could potentially revolutionize the existing treatment approaches for pancreatic cancer.

Mouse models in colon cancer, inferences, and implications

Mouse models of colorectal cancer (CRC) have been crucial in the identification of the role of genes responsible for the full range of pathology of the human disease and have proved to be dependable for testing anti-cancer drugs. Recent research points toward the relevance of tumor, angiogenic, and immune microenvironments in CRC progression to late-stage disease, as well as the treatment of it. This study examines important mouse models in CRC, discussing inherent strengths and weaknesses disclosed during their construction. It endeavors to provide both a synopsis of previous work covering how investigators have defined various models and to evaluate critically how researchers are most likely to use them in the future. Accumulated evidence regarding the metastatic process and the hope of using checkpoint inhibitors and immunological inhibitor therapies points to the need for a genetically engineered mouse model that is both immunocompetent and autochthonous.

A budding concept with certain microbiota, anti-proliferative family proteins, and engram theory for the innovative treatment of colon cancer

Inflammatory bowel disease (IBD) is a multifactorial chronic disease. Patients with IBD have an increased risk of developing colorectal cancer which has become a major health concern. IBD might exert a role of engrams for making the condition of specific inflammation in the gut. Dysregulation of immune cells induced by the command of engrams might be crucial in the pathogenesis of damages in gut epithelium. The anti-proliferative (APRO) family of anti-proliferative proteins characterized by immediate early responsive gene-products that might be involved in the machinery of the carcinogenesis in IBD. Herein, it is suggested that some probiotics with specific bacteria could prevent the development and/or progression of the IBD related tumors. In addition, consideration regarding the application of studying APRO family proteins for the comprehension of IBD related tumors has been presented. It is hypothesized that overexpression of Tob1, a member of APRO family proteins, in the epithelium of IBD could suppress the function of adjacent cytotoxic immune cells possibly via the paracrine signaling.

Methylation Mediated Downregulation of TOB1-AS1 and TOB1 Correlates with Malignant Progression and Poor Prognosis of Esophageal Squamous Cell Carcinoma

BACKGROUND

TOB1, a member of the transducer of erbB-2 /B-cell translocation gene family, was detected to be down-regulated in ESCC by RNA sequencing. TOB1-AS1, a head-to-head antisense lncRNA with TOB1, was down-regulated in several cancers. However, the roles of them in esophageal squamous cell carcinoma (ESCC) remained unclarified.

AIMS

To investigate the roles and functions of TOB1-AS1 and TOB1 in ESCC tumorigenesis.

MATERIALS AND METHODS

The expression levels, methylation status, biological function and mechanisms of TOB1-AS1 and TOB1 in ESCC were, respectively, detected.

RESULTS

Frequent down-regulation of TOB1-AS1 and TOB1 was verified in esophageal cancer cells and ESCC tissues, and there was a positive correlation between them in ESCC tissues. The CpG sites hypermethylation within proximal promoter of TOB1-AS1 and TOB1 could lead to transcriptional inhibition of both genes. Furthermore, expression and proximal promoter methylation status of TOB1-AS1 or TOB1 may be associated with ESCC patients' prognosis. TOB1-AS1 and TOB1 may function as tumor suppressors by inhibiting growth, migration, and invasion of esophageal cancer cells. Up-regulation of TOB1-AS1 increased expression level of TOB1, and TOB1-AS1 could work as a ceRNA to modulate ATF3 expression via competitively binding with miR-103a-2-5p. Meanwhile, ATF3, as a transcription factor, could regulate transcription of TOB1; down-regulation of TOB1-AS1 in ESCC led to decreased expression of ATF3 through ceRNA mechanism, and further influenced the transcription of TOB1.

CONCLUSION

TOB1-AS1 and TOB1 may act as tumor suppressors and may serve as potential targets for antitumor therapy in ESCC.

Magic and mystery of microRNA-32

MicroRNAs (miRNAs) are a group of endogenous, small (∼22 nts in length) noncoding RNA molecules that function specifically by base pairing with the mRNA of genes and regulate gene expression at the post-transcriptional level. Alterations in miR-32 expression have been found in numerous diseases and shown to play a vital role in cell proliferation, apoptosis, oncogenesis, invasion, metastasis and drug resistance. MiR-32 has been documented as an oncomiR in the majority of related studies but has been also verified as a tumour suppressor miRNA in conflicting reports. Moreover, it has a crucial role in metabolic and cardiovascular disorders. This review provides an in-depth look into the most recent finding regarding miR-32, which is involved in the expression, regulation and functions in different diseases, especially tumours. Additionally, this review outlines novel findings suggesting that miR-32 may be useful as a noninvasive biomarker and as a targeted therapeutic in several diseases.

Identification of GSPT1 as prognostic biomarker and promoter of malignant colon cancer cell phenotypes via the GSK-3β/CyclinD1 pathway

Colon cancer is the third most common malignant tumor and its mortality rate ranks fourth among all malignant tumor types. Bioinformatics analysis has shown that GSPT1 is dysregulated in colon cancer and is associated with tumor progression. However, the underlying mechanism remains unclear. To address this research gap, we examined the impact of GSPT1 on cell proliferation, apoptosis, migration, and invasion in vitro as well as tumor growth in vivo in colon cancer by using a Cell Counting Kit-8 assay, flow cytometry, transwell migration assay, transwell invasion assay, and tumor xenograft model-based analysis, respectively. GSPT1 was significantly up-regulated in colon cancer tissues and cell lines. High GSPT1 expression was correlated with a larger tumor size. Depletion of GSPT1 suppressed cell proliferation, migration, and invasion-induced colon cancer cell apoptosis in vitro and restrained tumorigenicity in vivo in HCT116 colon cancer cells. Taken together, our findings suggest that the GSPT1/GSK pathway exerts tumor-promoting actions in colon cancer oncogenesis and progression. The GSPT1/GSK pathway may thus be an effective target for controlling colon cancer.

NEDD4 triggers FOXA1 ubiquitination and promotes colon cancer progression under microRNA-340-5p suppression and ATF1 upregulation

NEDD4 is an E3 ubiquitin ligase that recognizes substrates through protein-protein interactions and is involved in cancer development. This study aimed to elucidate the function of NEDD4 in colon cancer (CC) progression and its mechanism of action. NEDD4 was abundantly expressed in CC tissues and cells, and the overexpression of NEDD4 promoted the growth and metastasis of xenograft tumours as well as the tumorigenesis rate of primary CC in mouse models. In in vitro experiments, the silencing (or upregulation) of NEDD4 inhibited (or increased) the viability, invasion, and epithelial-to-mesenchymal transition of CC cells. The binding relationships between NEDD4 and FOXA1, FOXA1 and microRNA (miRNA)-340-5p, and miR-340-5p and ATF1 were validated by Co-immunoprecipitation, chromatin immunoprecipitation and luciferase assays, and NEDD4 was demonstrated to trigger FOXA1 ubiquitination and degradation. FOXA1 transcriptionally activated miR-340-5p, which subsequently bound to ATF1 mRNA. The upregulation of FOXA1 or miR-340-5p or the downregulation of ATF1 blocked certain functions of NEDD4 in CC cells. Altogether, NEDD4 was demonstrated to trigger FOXA1 ubiquitination and promote CC progression under the involvement of microRNA-340-5p suppression and ATF1 upregulation.

Identification and Development of Long Non-coding RNA Associated Regulatory Network in Pancreatic Adenocarcinoma

Background and Aims

Pancreatic adenocarcinoma (PAAD) is the most lethal cancer type around the world. With the in-depth exploration of the function of long non‐coding RNAs (lncRNAs), the competing endogenous RNA (ceRNA) mechanism has shown its potential to partially reveal the pathogenesis of PAAD. This study aimed to construct a lncRNA‐associated ceRNA network and explore ceRNA regulatory axes with experimental and prognostic value in PAAD.

Methods

First, we applied differential expression analysis in the TCGA_PAAD dataset. Then, interaction analysis and survival analysis in multiple RNA interaction databases were conducted to construct a ceRNA network. Finally, a potential regulatory axis was validated using clinical samples and cell lines by quantitative realtime PCR (qRT‐PCR).

Results

A ceRNA network comprising 13 lncRNAs, 96 miRNAs, and 30 mRNAs was successfully constructed. Survival analysis further narrowed this network to five lncRNAs, three miRNAs, and seven mRNAs, which were significantly associated with patients’ overall survival. A potential regulatory axis CASC8-miR-129-5p-TOB1 was further experimentally validated. The expression of these genes was associated with clinicopathological factors and their expression trend was consistent with ceRNA mechanism. Specifically, knockdown of lncRNA-CASC8 led to the overexpression of miR-129-5p and down-regulation of TOB1, while overexpression of CASC8 showed opposite effects.

Conclusion

This novel ceRNA regulatory network could provide new insight into the pathogenesis of PAAD. The new regulatory axis CASC8-miR-129-5p-TOB1 might serve as a potential therapeutic target for patients.

Analysis of CNOT Family Gene Expression, Clinicopathological Features, and Prognosis Value in Hepatocellular Carcinoma

The carbon catabolite repressor 4-negative on TATA (CCR4-NOT) complex, abbreviated CNOT, has deadenylation and 3'-5' exonuclease activity, mediates deadenylation in the degradation of RNA, initiates the exonuclease degradation pathway, and participates in tumor gene regulation. CNOT proteins comprise a family of global transcriptional regulators that are evolutionarily conserved in eukaryotic cells. Several subunit types of the CNOT complex have been discovered; however, little is known about the role of different subunits in tumorigenesis and development. We observed overexpression of CNOT1-11 in liver cancer and correlations with clinicopathological characteristics. The expression of some CNOTs subunits was associated with histological grades, lymph node metastasis, and tumor stages in patients with hepatocellular carcinoma (HCC). Our data suggested that some CNOTs can be used as predictors of poor prognosis in HCC patients. At the same time, we conducted an analysis of CNOTs mutations in HCC patients. Moreover, we selected CNOT6, CNOT10, and CNOT11 for protein interaction network analysis and Gene Ontology enrichment analysis to investigate their related biological processes and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Finally, the results of western blot and quantitative reverse transcription-PCR (qRT-PCR) experiments were consistent with the database findings. Results of this study suggest that CNOT6, CNOT10, and CNOT11, acting as regulators of transcription, may play an important role in the development of HCC and may serve as biological markers in the diagnosis and prognosis of HCC.

HOXA13 promotes colon cancer progression through β-catenin-dependent WNT pathway

Human class I homeobox A13 (HOXA13) was initially identified as a transcription factor and has an important role in embryonic development and malignant transformation. However, the clinical significance and the molecular mechanisms of HOXA13 in colon cancer development and progression are still unknown. In this study, we found that HOXA13 was highly expressed in colon cancer tissues, and its expression was associated with histological grade, T stage, N stage and tumour size. In vitro studies showed that HOXA13 promoted colon cancer cell proliferation, migration and invasion. Bioinformatics analysis revealed that HOXA13 expression was positively correlated with the WNT signalling pathway. In vitro studies showed that HOXA13 promoted the malignant phenotype of colon cancer cells by facilitating the nuclear translocation of β-Catenin. Moreover, XAV939, an inhibitor of β-Catenin, reversed the HOXA13-mediated effects on invasion and proliferation of colon cancer cells. In vivo studies further verified that HOXA13 promoted tumour formation through the Wnt/β-Catenin pathway. Collectively, these results suggest that HOXA13 is a potential oncogene that functions by promoting the nuclear translocation of β-Catenin, thereby maintaining the proliferation and metastasis of colon cancer.

LncRNA WEE2-AS1 promotes proliferation and inhibits apoptosis in triple negative breast cancer cells via regulating miR-32-5p/TOB1 axis

Triple negative breast cancer (TNBC) is a malignant breast cancer subtype with poor prognosis. Recent studies have revealed the critical roles of dysregulated long non-coding RNAs (lncRNAs) in many cancer types, including TNBC. LncRNA WEE2 antisense RNA 1 (WEE2-AS1) has been reported to be able to promote the progression of hepatocellular carcinoma, but the function of WEE2-AS1 in TNBC is still unknown. Therefore, in this study, we specifically researched the role of WEE2-AS1 and probed its molecular mechanism in TNBC cells. Our results showed that WEE2-AS1 was up-regulated in TNBC cell lines, and WEE2-AS1 knockdown could inhibit TNBC cell proliferation, promote apoptosis, and suppress migration and invasion. Further, we found that miR-32-5p was down-regulated in TNBC cells and could be sponged by WEE2-AS1. Moreover, miR-32-5p could target its downstream gene transducer of ERBB2, 1 (TOB1), which was highly expressed and could play the oncogenic role in TNBC cells. Through rescue assays, we proved that WEE2-AS1/miR-32-5p/TOB1 axis could modulate cancer progression in TNBC cells. In conclusion, our results demonstrated the oncogenic function of lncRNA WEE2-AS1 in TNBC cells, providing a novel insight into TNBC therapy.

IM-12 activates the Wnt-β-catenin signaling pathway and attenuates rtPA-induced hemorrhagic transformation in rats after acute ischemic stroke

Hemorrhagic transformation (HT) is a devastating complication for patients with acute ischemic stroke (AIS) who are treated with tissue plasminogen activator (tPA). HT is associated with high morbidity and mortality, but no effective treatments are currently available to reduce the risk of HT. Therefore, methods to prevent HT are urgently needed. In this study, we used IM-12, an inhibitor of glycogen synthase kinase 3β (GSK-3β), to evaluate the role of the Wnt-β-catenin signaling pathway in recombinant tPA (rtPA)-induced HT. Sprague-Dawley rats were subjected to a middle cerebral artery occlusion (MCAO) model of ischemic stroke, and then were either administered rtPA, rtPA combined with IM-12, or the vehicle at 4 h after stroke was induced. Our results indicate that rats subjected to HT had more severe neurological deficits, brain edema, and blood-brain barrier (BBB) breakdown, and had a greater infarction volume than the control group. Rats treated with IM-12 had improved outcomes compared with those of rats treated with rtPA alone. Moreover, IM-12 increased the protein expression of β-catenin and downstream proteins while suppressing the expression of GSK-3β. These results suggest that IM-12 reduces rtPA-induced HT and attenuates BBB disruption, possibly through activation of the Wnt-β-catenin signaling pathway, and provides a potential therapeutic strategy for preventing tPA-induced HT after AIS.

MiR-32-5p Regulates Radiosensitization, Migration And Invasion Of Colorectal Cancer Cells By Targeting TOB1 Gene

Background

MicroRNAs (miRNAs) play key roles in the development and progression of various cancers. However, the precise functions and regulation mechanisms of miRNAs in human tumors remain elusive.

Methods

Quantitative real time-PCR (qRT-PCR) was performed to detect the level of miR-32-5p in colorectal cancer tissues. The relationships between miR-32-5p level with clinicopathological characteristics and prognosis were analyzed. The miR-32-5p inhibitor was employed to knock down the expression of miR-32-5p. The overexpression plasmid and si-RNA targeting TOB1 were generated. Clone formation assays under radiant exposure were used to evaluate the radiosensitization. Transwell migration and invasion were employed to test the ability of cell migration and invasion. Luciferase reporter assays were used to confirm the regulation of miR-32-5p on the expression of TOB1. Rescue experiments were conducted to investigate the effects of TOB1 on the functions of miR-32-5p.

Results

In this study, we found that miR-32-5p was significantly upregulated in colorectal cancer tissues compared with adjacent normal tissues. The level of miR-32-5p was positively correlated with tumor differentiation and metastasis. Log-rank tests showed that high level of miR-32-5p was significantly correlated with poor overall survival and disease-free survival. Anti-miR-32-5p remarkably enhanced the radiosensitivity and inhibited migration and invasion of colorectal cancer cells. In addition, overexpression of TOB1 obviously increased the radiosensitivity and inhibited migration and invasion of colorectal cancer cells. Moreover, bioinformatics analysis and luciferase reporter assays demonstrated that miR-32-5p suppressed the expression of TOB1 through directly binding to the 3ʹ-UTR of TOB1 mRNA. Rescue experiments indicated that miR-32-5p regulated the radiosensitivity, migration and invasion of colorectal cancer cells through inhibiting TOB1 expression.

Conclusion

This study suggested that miR-32-5p may serve as a prognostic and therapeutic target for colorectal cancer, and downregulation of miR-32-5p enhanced the radiosensitivity and inhibited migration and invasion through promoting TOB1 expression.