Upregulation of DPY30 promotes cell proliferation and predicts a poor prognosis in cholangiocarcinoma

Protein regulator of cytokinesis 1 accentuates cholangiocarcinoma progression via mTORC1-mediated glycolysis

This study aimed to investigate the expression of protein regulator of cytokinesis 1 (PRC1) in cholangiocarcinoma (CHOL) and elucidate its potential impact as well as the underlying mechanisms governing the progression of CHOL. In this study, we used CHOL cells (HUCCT1, RBE, and CCLP1) and conducted a series of experiments, including qRT-PCR, cell counting kit-8 assays, EdU assays, flow cytometry, wound healing assays, Transwell assays, western blotting, double luciferase assays, and ELISA. Subsequently, a mouse model was established using cancer cell injections. Haematoxylin-eosin staining, along with Ki67 and TUNEL assays, were employed to assess tissue histopathology, cell proliferation, and apoptosis. Our findings revealed significantly elevated PRC1 expression in CHOL. According to bioinformatics analysis, it was found that the increased PRC1 level is correlated with the high tumour grades, metastases, and unfavourable prognoses. Notably, PRC1 knockdown inhibited cell viability, proliferation, migration, and invasion while promoting apoptosis in CHOL cells. Analysing TCGA-CHOL data and utilising transcription factor prediction tools (hTFtarget and HumanTFDB), we identified that genes positively correlated with PRC1 in TCGA-CHOL intersect with predicted transcription factors, revealing the activation of PRC1 by forkhead box protein M1 (FOXM1). Moreover, PRC1 was found to exert regulatory control over glycolysis and the mammalian target of rapamycin complex 1 (mTORC1) pathway in the context of CHOL based on KEGG and GSEA analysis. Collectively, these results underscore the pivotal role of PRC1 in CHOL progression, wherein it modulates glycolysis and the mTORC1 pathway under the regulatory influence of FOXM1.

DPY30 promotes colorectal carcinoma metastasis by upregulating ZEB1 transcriptional expression

DPY30 belongs to the core subunit of components of the histone lysine methyltransferase complex, which is implicated in tumorigenesis, cell senescence, and other biological events. However, its contribution to colorectal carcinoma (CRC) progression and metastasis has yet to be elucidated. Therefore, this study aimed to investigate the biological function of DPY30 in CRC metastasis both in vitro and in vivo. Herein, our results revealed that DPY30 overexpression is significantly positively correlated with positive lymph nodes, epithelial-mesenchymal transition (EMT), and CRC metastasis. Moreover, DPY30 knockdown in HT29 and SW480 cells markedly decreased EMT progression, as well as the migratory and invasive abilities of CRC cells in vitro and lung tumor metastasis in vivo. Mechanistically, DPY30 increased histone H3K4me3 level and promoted EMT and CRC metastasis by upregulating the transcriptional expression of ZEB1. Taken together, our findings indicate that DPY30 may serve as a therapeutic target and prognostic marker for CRC.

Identification and validation of DPY30 as a prognostic biomarker and tumor immune microenvironment infiltration characterization in esophageal cancer

Esophageal cancer (ESCA) is a lethal malignancy and is associated with the alterations of various genes and epigenetic modifications. The protein dpy-30 homolog (DPY30) is a core member of histone H3K4 methylation catalase and its dysfunction is associated with the occurrence and development of cancer. Therefore, the present study investigated the role of DPY30 in ESCA and evaluated the association between the expression of DPY30, the clinicopathological characteristics of ESCA and the tumor immune microenvironment. It conducted a comprehensive analysis of DPY30 in patients with ESCA using The Cancer Genome Atlas (TCGA) database and clinical tissue microarray specimens of ESCA. Immunohistochemistry was performed to assess the expression levels of DPY30 in tissues. Receiver operating curve analysis, Kaplan-Meier survival analysis and Cox regression analysis were performed to identify the diagnostic and prognostic value of DPY30. Gene Set Enrichment Analysis, protein-protein interaction network and Estimation of Stromal and Immune cells in Malignant Tumor tissues using the Expression data were used to screen DPY30-associated genes and evaluate the immune score of the TCGA samples. The results demonstrated that the expression of mRNA and protein levels of DPY30 were significantly upregulated in tumor tissues compared with normal tissue samples. The expression of DPY30 was closely associated with the poor prognosis of patients with ESCA. The present study also found that DPY30 expression and the pathological characteristics of ESCA were significantly correlated. Additionally, the expression of DPY30 demonstrated a significant positive correlation with various immune cells infiltration. The results suggested that DPY30 might influence tumor immune infiltration. In conclusion, the findings suggested that DPY30 might be a potential prognostic biomarker and an immunotherapeutic target in ESCA.

DPY30 promotes the growth and survival of osteosarcoma cell by regulating the PI3K/AKT signal pathway

Osteosarcoma (OS) is characterized by aggressive features including invasiveness and high incidence of metastasis. OS patients with metastases are difficult to treat and suffer from a poor prognosis. DPY30 (protein dpy-30 homolog) is a key component of SET1/MLL family of H3K4 methyltransferases, which is implicated in the progression of multiple cancers. However, the potential functional engagement of DPY30 in OS remains to be unveiled. The objective of this study is to investigate the potential roles of DPY30 in the regulation of malignant phenotypes of OS cells. We examined DPY30 expression from a published dataset (GSE28424) as well as in OS tissues and adjacent normal tissues from OS patients. The association of DPY30 expression level and clinicopathologic parameters was assessed by Chi-square test. The role of DPY30 in regulating the malignant phenotype of OS cells and tumorigenesis was examined by in vitro functional assays and xenograft mouse model. We reported an upregulation of DPY30 in OS tumor tissues in both published dataset and clinical samples. A high level of DPY30 expression was associated with larger tumor size and more metastasis in OS patients, as well as poor overall survival. DPY30 knockdown in OS cells significantly impairs proliferation, migration and invasion, but induced cellular apoptosis. We further demonstrated that the agonist of PI3K/AKT pathway can rescue the inhibitory effects of DPY30 knockdown in OS cells. Together, our data indicate that DPY30 functions as an oncogene to promote the malignancy of OS cells possibly through PI3K/AKT pathway. The dependency of OS cells on DPY30 overexpression is a targetable vulnerability in OS cells.

DPY30 acts as an ASH2L-specific stabilizer to stimulate the enzyme activity of MLL family methyltransferases on different substrates

Dumpy-30 (DPY30) is a conserved component of the mixed lineage leukemia (MLL) family complex and is essential for robust methyltransferase activity of MLL complexes. However, the biochemical role of DPY30 in stimulating methyltransferase activity of MLL complexes remains elusive. Here, we demonstrate that DPY30 plays a crucial role in regulating MLL1 activity through two complementary mechanisms: A nucleosome-independent mechanism and a nucleosome-specific mechanism. DPY30 functions as an ASH2L-specific stabilizer to increase the stability of ASH2L and enhance ASH2L-mediated interactions. As a result, DPY30 promotes the compaction and stabilization of the MLL1 complex, consequently increasing the HKMT activity of the MLL1 complex on diverse substrates. DPY30-stabilized ASH2L further acquires additional interfaces with H3 and nucleosomal DNA, thereby boosting the methyltransferase activity of the MLL1 complex on nucleosomes. These results collectively highlight the crucial and conserved roles of DPY30 in the complex assembly and activity regulation of MLL family complexes.

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DPY30 stimulates the enzyme activity of MLL complexes on broad-spectrum substrates

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DPY30 functions as an ASH2L-specific stabilizer

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DPY30 promotes the compaction and stabilization of the MLL1 complex

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DPY30-stabilized ASH2L acquires additional interfaces with H3 and nucleosomal DNA

Metabolic reprogramming in cholangiocarcinoma

Metabolic reprogramming is a hallmark of cancer and allows tumour cells to meet the increased energy demands required for rapid proliferation, invasion, and metastasis. Indeed, many tumour cells acquire distinctive metabolic and bioenergetic features that enable them to survive in resource-limited conditions, mainly by harnessing alternative nutrients. Several recent studies have explored the metabolic plasticity of cancer cells with the aim of identifying new druggable targets, while therapeutic strategies to limit the access to nutrients have been successfully applied to the treatment of some tumours. Cholangiocarcinoma (CCA), a highly heterogeneous tumour, is the second most common form of primary liver cancer. It is characterised by resistance to chemotherapy and poor prognosis, with 5-year survival rates of below 20%. Deregulation of metabolic pathways have been described during the onset and progression of CCA. Increased aerobic glycolysis and glutamine anaplerosis provide CCA cells with the ability to generate biosynthetic intermediates. Other metabolic alterations involving carbohydrates, amino acids and lipids have been shown to sustain cancer cell growth and dissemination. In this review, we discuss the complex metabolic rewiring that occurs during CCA development and leads to unique nutrient addiction. The possible role of therapeutic interventions based on metabolic changes is also thoroughly discussed.

The DPY30-H3K4me3 Axis-Mediated PD-L1 Expression in Melanoma

Background

DPY30 is a common subunit of the human SET1/MLL complex and is an essential protein required for the activity of SET1/MLL methyltransferase. DPY30 regulates the histone H3K4 modification, and dysfunction of DPY30 might contribute to the regulation of cancer immune evasion. However, the functions and regulation of DPY30 in the expression of programmed cell death ligand 1 (PD-L1) is still not completely explored.

Methods

Various online databases were used for data processing and visualization, including UALCAN, Oncomine, cBioPortal, SangerBox, TISIDB, TIMER, and GEPIA databases. The expression of DPY30 and PD-L1 in melanoma tissues were evaluated by IHC. Chromatin Immunoprecipitation (ChIP), RT-PCR and flow cytometry were used to elucidate the underlying molecular mechanism of PD-L1 expression regulation and its function.

Results

The mRNA level of DPY30 in melanoma was higher than in normal tissues. The expression of DPY30 was positively associated with TMB, neoantigens and PD-L1 expression. Furthermore, DPY30 expression showed significant positive correlations with immune suppressor cells and ICP genes involved in T-cell exhaustion. IHC showed that the positive rates of DPY30 and PD-L1 in melanoma tissues were 62% and 58%, respectively. Correlation analysis revealed that DPY30 over-expression was positively associated with PD-L1 expression. Silencing of DPY30 by specific siRNA significantly inhibited PD-L1 expression. ChIP analysis revealed that H3K4me3 levels were enriched in the proximal PD-L1 promoter region in tumor cells. Inhibition of DPY30 still suppressed the PD-L1 level in IFN-γ treated MMAC-SF cells. Furthermore, the apoptosis of PD1⁺ T-cells in co-culture with MMAC-SF cells by knockdown of DPY30 were markedly reduced.

Conclusion

This study shows the roles of DPY30 in regulating the cancer immune evasion in melanoma. Targeting the DPY30-H3K4me3 axis might be an alternative approach to enhance the efficacy of checkpoint immunotherapy.

Construction of a prognostic model with histone modification-related genes and identification of potential drugs in pancreatic cancer

Background

Pancreatic cancer (PC) is a highly fatal and aggressive disease with its incidence and mortality quite discouraging. An effective prediction model is urgently needed for the accurate assessment of patients’ prognosis to assist clinical decision-making.

Methods

Gene expression data and clinicopathological data of the samples were acquired from The Cancer Genome Atlas (TCGA), Genotype-Tissue Expression (GTEx), and Gene Expression Omnibus (GEO) databases. Differential expressed genes (DEGs) analysis, univariate Cox regression analysis, least absolute shrinkage and selection operator (LASSO) regression analysis, random forest screening and multivariate Cox regression analysis were applied to construct the risk signature. The effectiveness and independence of the model were validated by time-dependent receiver operating characteristic (ROC) curve, Kaplan–Meier (KM) survival analysis and survival point graph in training set, test set, TCGA entire set and GSE57495 set. The validity of the core gene was verified by immunohistochemistry and our own independent cohort. Meanwhile, functional enrichment analysis of DEGs between the high and low risk groups revealed the potential biological pathways. Finally, CMap database and drug sensitivity assay were utilized to identify potential small molecular drugs as the risk model-related treatments for PC patients.

Results

Four histone modification-related genes were identified to establish the risk signature, including CBX8, CENPT, DPY30 and PADI1. The predictive performance of risk signature was validated in training set, test set, TCGA entire set and GSE57495 set, with the areas under ROC curve (AUCs) for 3-year survival were 0.773, 0.729, 0.775 and 0.770 respectively. Furthermore, KM survival analysis, univariate and multivariate Cox regression analysis proved it as an independent prognostic factor. Mechanically, functional enrichment analysis showed that the poor prognosis of high-risk population was related to the metabolic disorders caused by inadequate insulin secretion, which was fueled by neuroendocrine aberration. Lastly, a cluster of small molecule drugs were identified with significant potentiality in treating PC patients.

Conclusions

Based on a histone modification-related gene signature, our model can serve as a reliable prognosis assessment tool and help to optimize the treatment for PC patients. Meanwhile, a cluster of small molecule drugs were also identified with significant potentiality in treating PC patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-01928-6.