TCF12 overexpression as a poor prognostic factor in ovarian cancer

TCF12 Transcriptionally Activates SPHK1 to Induce Osteosarcoma Angiogenesis by Promoting the S1P/S1PR4/STAT3 Axis

Transcription factor 12 (TCF12) is a known oncogene in many cancers. However, whether TCF12 can regulate malignant phenotypes and angiogenesis in osteosarcoma is not elucidated. In this study, we demonstrated increased expression of TCF12 in osteosarcoma tissues and cell lines. High TCF12 expression was associated with metastasis and poor survival rate of osteosarcoma patients. Knockdown of TCF12 reduced the proliferation, migration, and invasion of osteosarcoma cells. TCF12 was found to bind to the promoter region of sphingosine kinase 1 (SPHK1) to induce transcriptional activation of SPHK1 expression and enhance the secretion of sphingosine-1-phosphate (S1P), which eventually resulted in the malignant phenotypes of osteosarcoma cells. In addition, S1P secreted by osteosarcoma cells promoted the angiogenesis of HUVECs by targeting S1PR4 on the cell membrane to activate the STAT3 signaling pathway. These findings suggest that TCF12 may induce transcriptional activation of SPHK1 to promote the synthesis and secretion of S1P. This process likely enhances the malignant phenotypes of osteosarcoma cells and induces angiogenesis via the S1PR4/STAT3 signaling pathway.

Systematic analysis of DNA methylation-mediated TF dysregulation on lncRNAs reveals critical roles in tumor immunity

Emerging evidence suggests that DNA methylation affects transcriptional regulation and expression perturbations of long non-coding RNAs (lncRNAs) in cancer. However, a comprehensive investigation into the transcriptional control of DNA methylation-mediated dysregulation of transcription factors (TFs) on lncRNAs has been lacking. Here, we integrated the transcriptome, methylome, and regulatome across 21 human cancers and systematically identified the transcriptional regulation of DNA methylation-mediated TF dysregulations (DMTDs) on lncRNAs. Our findings reveal that TF regulation of lncRNAs is significantly impacted by DNA methylation. Comparative analysis of DMTDs on mRNAs revealed a conserved pattern of TFs involvement. Pan-cancer Methylation TFs (MethTFs) and Methylation LncRNAs (MethLncRNAs) were identified, and were found to be closely associated with cancer hallmarks and clinical features. In-depth analysis of co-expressed mRNAs with pan-cancer MethLncRNAs unveiled frequent disruptions in cancer immunity, particularly in the context of inflammatory response. Furthermore, we identified five immune-related network modules that contribute to immune cell infiltration in cancer. Immune-related subtypes were subsequently classified, characterized by high levels of immune cell infiltration, expression of immunomodulatory genes, and relevant immune cytolytic activity score, major histocompatibility complex score, response to chemotherapy, and prognosis. Our findings provide valuable insights into cancer immunity from the epigenetic and transcriptional regulation perspective.

Transcription factor 12-mediated self-feedback regulatory mechanism is required in DUX4 fusion leukaemia

BACKGROUND

IGH::DUX4 is frequently observed in 4% B-cell acute lymphoblastic leukaemia patients. Regarding the IGH::DUX4-driven transactivation and alternative splicing, which are the main reasons behind this acute leukaemia outbreak, it remains unclear how transcriptional cofactors contribute to this oncogenic process. Further investigation is required to elucidate their specific role in leukaemogenesis.

METHODS

In order to investigate the cofactors of IGH::DUX4, integrated mining of Chromatin immunoprecipitation (ChIP)-sequencing and RNA-sequencing of leukaemia cells and patient samples were conducted. Furthermore, to elucidate the synergistic interaction between transcription factor 12 (TCF12) and IGH::DUX4, knockdown and knockout experiment, mammalian two-hybridisation assay, co-immunoprecipitation and in situ proximity ligation assays were carried out. Additionally, to further investigate the direct interaction between TCF12 and IGH::DUX4, AI-based structural simulations were utilised. Finally, to validate the synergistic role of TCF12 in promoting IGH::DUX4 leukaemia, cell proliferation, apoptosis and drug sensitivity experiments were performed.

RESULTS

In this study, we observed that the IGH::DUX4 target gene TCF12 might be an important cofactor/helper for this oncogenic driver. The co-expression of IGH::DUX4 and TCF12 resulted in enhanced DUX4-driven transactivation. Supportively, knockdown and knockout of TCF12 significantly reduced expression of IGH::DUX4-driven target genes in leukaemia REH (a precursor B-cell leukaemia cell line) and NALM-6 cells (a precursor B-cell leukaemia cell line). Consistently, in TCF12 knockout cells, the expression of structure-based TCF12 mutant, but not wild-type TCF12, failed to restore the TCF12-IGH::DUX4 crosstalk and the synergistic transactivation. More importantly, the breakdown in TCF12-IGH::DUX4 cooperation impaired IGH::DUX4-driven leukaemia cell survival, caused sensitivity to the chemotherapy.

CONCLUSIONS

Altogether, these results helped to define a previously unrecognised TCF12-mediated positive self-feedback regulatory mechanism in IGH::DUX4 leukaemia, which holds the potential to function as a pivotal drug target for the management of this particular form of leukaemia.

HIGHLIGHTS

Transcription factor 12 (TCF12) is a new novel cofactor in IGH::DUX4 transcriptional complexes/machinery. TCF12 mediates a positive self-feedback regulatory mechanism in IGH::DUX4-driven oncogenic transaction. IGH::DUX4-TCF12 structure/cooperation might represent a potent target/direction in future drug design against B-cell acute lymphoblastic leukaemia.

TCF12 Activates TGFB2 Expression to Promote the Malignant Progression of Melanoma

As one of the most common malignant tumors, melanoma is a serious threat to human health. More than half of melanoma patients have a BRAF mutation, and 90% of them have a BRAF(V600E) mutation. There is a targeted therapy for patients using a BRAF(V600E) inhibitor. However, no response to treatment is generally inevitable due to the heterogeneity of melanoma. Coupled with its high metastatic character, melanoma ultimately leads to poor overall survival. This study aimed to explore the possible mechanisms of melanoma metastasis and identify a more effective method for the treatment of melanoma. In this paper, we report that TCF12 expression is higher in melanoma, especially in metastatic tumors, through analyzing data from TCGA. Then, cell proliferation, colony formation, and transwell assays show that the upregulated expression of TCF12 can promote proliferation and metastasis of melanoma cells in vitro. The same result is confirmed in the subcutaneous tumor formation assay. Moreover, TGFB2 is identified as a direct downstream target of TCF12 by RNA-seq, qPCR, immunoblotting, ChIP, and a dual luciferase reporting assay. Interestingly, depletion of TCF12 can sensitize melanoma to BRAF inhibition both in vitro and in vivo. Overall, our results demonstrate that TCF12 promotes melanoma progression and can be a potential tumor therapeutic target.

Roles of circular RNAs in regulating the development of glioma

BACKGROUND

Glioma is the most common malignant tumor in the central nervous system. In patients with glioma, the prognosis is poor and median survival is only 12-15 months. With the recent development of sequencing technology, important roles of noncoding RNAs are being discovered in cells, especially those of circular RNAs (circRNAs). Because circRNAs are stable, abundant, and highly conserved, they are regarded as novel biomarkers in the early diagnosis and prognosis of diseases.

PURPOSE

In this review, roles and mechanisms of circRNAs in the development of glioma are summarized.

METHODS

This paper collects and reviews relevant PubMed literature.

CONCLUSION

Several classes of circRNAs are highly expressed in glioma and are associated with malignant biological behaviors of gliomas, including proliferation, migration, invasion, apoptosis, angiogenesis, and drug resistance. Further studies are needed to clarify the roles of circRNAs in glioma and to determine whether it is possible to increase therapeutic effects on tumors through circRNA intervention.

TCF12 activates MAGT1 expression to regulate the malignant progression of pancreatic carcinoma cells

As a highly malignant gastrointestinal tumor, pancreatic carcinoma (PC) has poor prognosis due to its low early diagnosis rate, advanced tumor resection and chemotherapy resistance. Magnesium transporter 1 (MAGT1) is a magnesium ion transporter located on the cell membrane, which shows promotive effects on biological behaviors of multiple tumor cells. The aim of the present study was to investigate the role of MAGT1 in the progression of PC and its potential molecular mechanism. Based on the Gene Expression Profiling Interactive Analysis website, MAGT1 was highly expressed in tissues from patients with PC and was associated with poor prognosis. In functional experiments, MAGT1 was highly expressed in PC cell lines. The Cell Counting Kit-8, gap closure and Transwell assays, and western blot analysis, were used to investigate the effects of MAGT1 overexpression or knockdown on the biological behaviors of PC cells. It was found that MAGT1 promoted the proliferation, migration and invasion of PC cells in vitro. According to the Encyclopedia of RNA Interactomes website, transcription factor 12 (TCF12) mRNA expression level was positively correlated with MAGT1 expression level in the tissues from patients with PC. Positive targeting regulation of MAGT1 by TCF12 was also confirmed using a dual-luciferase gene reporter assay and chromatin immunoprecipitation. In addition, knockdown of TCF12 expression inhibited the proliferation and migration of PC cells, but overexpression of MAGT1 expression partly reversed this. These results suggested that TCF12 could promote the proliferation, migration and invasion of PC cells by activating MAGT1 expression, which was associated with poor prognosis. These findings suggest that MAGT1 could be a promising biomarker for the occurrence, progression and prognosis of PC.

Screening and bioinformatics analysis of cellular proteins interacting with chicken bromodomain-containing protein 2 in DF-1 cells

1. Bromodomain-containing protein 2 (BRD2) is an important member of the BET protein family, which can specifically bind histone acetylated lysine to participate in gene transcriptional regulation, chromatin remodelling, cell proliferation and apoptosis. The following investigation of cellular proteins interacting with chBRD2 will be helpful in understanding the new functions of chBRD2 and the mechanism of NDV replication.2. The recombinant eukaryotic expression vector pEGFP-chBRD2 and empty vector pEGFP-C1 were transfected into DF-1 cells to overexpress GFP-chBRD2 and GFP, respectively. GO annotation, KEGG pathway, and protein-protein interaction network were used to analyse the cellular proteins interacting with chBRD2. In addition, one targeted protein was selected to verify its interaction with chBRD2 using fluorescent co-localisation and Co-IP.3. A total of 225 cellular proteins were identified that potentially interact with chBRD2. GO analysis showed that these play key roles in gene transcriptional regulation, cell cycle and development, immunity and viral infection. Further KEGG pathway analysis showed that these proteins were mainly involved in genetic information processing, immune system, cellular processes and translation. In addition, one targeted cellular protein chicken matrin 3 (chMATR3) was also identified as chBRD2 complex using both fluorescence co-localisation and Co-IP analysis.4. This study presents the interactome data of chBRD2 protein in DF-1 cells, which provides new information to understand the functions of chBRD2 and new targets for further investigating the replication and pathogenesis of NDV.

MicroRNA-211 attenuates cell proliferation in T-cell lymphoblastic lymphoma through targeting TCF12

T-cell lymphoblastic lymphoma (T-LBL) is a class of highly aggressive hematologic neoplasms originating from progenitor T-lymphocytes. MicroRNA (miRNA) is an endogenous RNA molecule with 22 nucleotides in length. Accumulated evidence suggests that miRNA functions as a key regulator in human cancer. Herein, by in silico analysis, we found that miR-211 was a decreased miRNA in T-LBL in high-throughput sequencing data, which was subsequently verified in our cohort. Low miR-211 was closely correlated with bulky disease, high ann arbor stage, relapse and poor prognosis. miR-211 was regulated by N6-methyladenosine (m⁶A) modification, specifically, m6A methyltransferase METTL14 methylated primary miR-211 (pri-miR-211), expediting pri-miR-211 processing via recruiting DGCR8. Functionally, miR-211 overexpression significantly reduced T-LBL cell viability, DNA synthesis rate and spheroid formation ability, whereas silencing of miR-211 had the opposite effects. In addition, we established the xenograft tumor model and found that miR-211 remarkably inhibited tumor growth in vivo. Further, TCF12 was the direct target of miR-211, miR-211 bound to TCF12 mRNA 3`-untranslated region (UTR) and increased its decay, overexpression of TCF12 could effectively rescue the weakened malignant behavior of T-LBL cells caused by miR-211 overexpression. Collectively, our data clearly demonstrate that miR-211 is a novel tumor suppressor in T-LBL, targeting of miR-211/TCF12 axis may be a potential treatment for T-LBL patients.

miR-218-5p inhibits the malignant progression of glioma via targeting TCF12

Several studies have shown the ability of transcription factor 12 (TCF12) to promote tumor malignant progression, but its function in glioma cells has not been fully elucidated. In this study, we analyzed the data from TCGA by bioinformatics and found that in glioma tissue, TCF12 was conspicuously highly expressed while miR-218-5p was significantly low-expressed. The downregulation of miR-218-5p was correlated with adverse prognosis in patients with glioma. miR-218-5p was found to be negatively associated with TCF12 by Pearson correlation analysis, and dual luciferase assay was employed to verify that miR-218-5p and TCF12 had a targeting relationship. qRT-PCR and Western blot assays were used to verify that the expression of TCF12 was regulated by its upstream regulator miR-218-5p. Moreover, cell experiments validated that overexpressed TCF12 could promote the proliferation, migration, and invasion of glioma cells and inhibit their apoptosis, whereas overexpressing miR-218-5p at the same time could reverse this phenomenon. Our study demonstrates the regulatory mechanism of the miR-218-5p/TCF12 axis in gliomas, which lays a foundation for searching for new therapeutic approaches for glioma.

GSG2 Promotes Development and Predicts Poor Prognosis of Ovarian Cancer

Purpose

Ovarian cancer is one of the most common malignant tumors in gynecology, whose treatment was seriously limited by the unclear understanding of molecular mechanism in disease development. GSG2, also known as Haspin, is a novel molecule found to be involved in human cancers.

Materials and Methods

In this study, immunohistochemical analysis was used to detect GSG2 expression in ovarian cancer tissues and corresponding normal tissues. Statistical analysis was performed to construct relationship between GSG2 and tumor characteristics as well as prognosis. Ovarian cell model with GSG2 knockdown was constructed through lentivirus-mediated transfection of shRNA, which was used in MTT assay, colony formation assay and flow cytometry for investigating the role of GSG2 in ovarian cancer. A human apoptosis antibody array was used to identify potential downstream apoptosis-related proteins of GSG2.

Results

The results demonstrated the upregulation of GSG2 in ovarian cancer, whose expression was positively related to tumor grade and AJCC stage, and negatively correlated with patients’ prognosis. Moreover, knockdown of GSG2 inhibited ovarian cancer development through suppressing cell growth and inducing cell apoptosis. Further exploration revealed that a variety of apoptosis-related and PI3K signaling pathway-related proteins may be implicated in the GSG2 induced regulation of ovarian cancer.

Conclusion

In summary, it was illustrated that GSG2 was involved in the development of ovarian cancer, which has the potential to become therapeutic target and prognostic indicator in ovarian cancer treatment.

CircRNA PIP5K1A promotes the progression of glioma through upregulation of the TCF12/PI3K/AKT pathway by sponging miR-515-5p

Background

Increasing studies have revealed that circular RNAs (CircRNAs) make great contributions to regulating tumor progression. Therefore, we intended to explore the expression characteristics, function, and related mechanisms of a novel type of circRNA, PIP5K1A, in glioma.

Methods

Firstly, reverse transcription-polymerase chain reaction (RT-PCR) was carried out to examine CircPIP5K1A expression in glioma tissues and adjacent normal tissues, and the correlation between CircPIP5K1A level and the clinical-pathological indicators of glioma was analyzed. Then, the CircPIP5K1A expression in various glioma cell lines was detected, and CircPIP5K1A overexpression and knockdown cell models were constructed. Subsequently, cell proliferation and viability were detected by the CCK8 method and BrdU staining. Cell apoptosis was detected by flow cytometry, and cell invasion was examined by Transwell assay. The expression of TCF12, PI3K/AKT pathway apoptotic related proteins (Caspase3, Bax, and Bcl2) and epithelial-mesenchymal transition (EMT) markers (E-cadherin, Vimentin, and N-cadherin) was determined by western blot or RT-PCR.

Results

The results manifested that CircPIP5K1A was upregulated in glioma tissues (compared with that in normal adjacent tissues), and overexpressed CircPIP5K1A was related to glioma volume and histopathological grade. Functionally, overexpressing CircPIP5K1A notably elevated glioma cell proliferation, invasion, and EMT and inhibited apoptosis both in vivo and in vitro. Besides, CircPIP5K1A upregulated TCF12 and PI3K/AKT activation. Bioinformatics analysis testified that miR-515-5p was a common target of CircPIP5K1A and TCF12, while the dual-luciferase reporter assay and RNA immunoprecipitation (RIP) experiment further confirmed that CircPIP5K1A targeted miR-515-5p, which bound the 3′-untranslated region (UTR) of TCF12.

Conclusions

Overall, the study illustrated that CircPIP5K1A is a potential prognostic marker in glioma and regulates glioma evolvement by modulating the miR-515-5p-mediated TCF12/PI3K/AKT axis.

Inhibitory effects of brusatol delivered using glycosaminoglycan‑placental chondroitin sulfate A‑modified nanoparticles on the proliferation, migration and invasion of cancer cells

Breakthroughs in cancer management result from the development of drugs that can be used for early diagnosis and effective treatment. Surgery, chemotherapy, radiotherapy and hormone therapy are the main anticancer therapies. However, traditional cancer chemotherapy is associated with serious systemic side effects. Nanoparticles (NPs) provide an effective solution for cancer treatment via the targeted delivery of drugs to cancer cells, while minimizing injury to normal cells. Glycosaminoglycan-placental chondroitin sulfate A (plCSA) is expressed in a number of tumor cells and trophoblasts. A plCSA-binding peptide (plCSA-BP) was isolated from malaria protein VAR2CSA, which can effectively promote the binding of lipid polymer NPs to tumor cells, thereby significantly enhancing the anticancer effect of encapsulated drugs. Brusatol is an important compound derived from Brucea javanica that exerts a multitude of biological effects, including inhibiting tumor cell growth, reducing the reproduction of malaria parasites, reducing inflammation and resisting virus invasion. In the present study, brusatol-loaded NPs (BNPs) or coumarin 6 NPs (CNPs), plCSA-BP and scrambled control peptide-bound BNPs or CNPs were prepared. Ovarian cancer cells (SKOV3), endometrial cancer cells (HEC-1-A) and lung cancer cells (A549) were treated with the NPs. The uptake of plCSA-CNPs by tumor cells was found to be markedly higher compared with that of other types of NPs. Further studies demonstrated that the plCSA-BNPs promoted the apoptosis of cancer cells more effectively and inhibited their proliferation, invasion and migration, accompanied by downregulation of matrix metalloproteinase (MMP)-2, MMP-9 and B-cell CLL/lymphoma 2 (BCL2) levels, but upregulation of BCL2-associated X protein BAX and cleaved caspase-3 levels. The results demonstrated the potential of brusatol delivered by plCSA-modified NPs as a chemotherapeutic agent for the targeted therapy of tumors by regulating the BCL2, BAX, cleaved caspase-3, MMP-2 and MMP-9 pathways, and indicated that it may be an effective and safe strategy for the treatment of various tumors.