CCRK is a novel signalling hub exploitable in cancer immunotherapy

KEAP1-NRF2 Interaction in Cancer: Competitive Interactors and Their Role in Carcinogenesis

An American Cancer Society report estimates the emergence of around 2 million new cancer cases in the US in 2024 [...].

Cyclin-dependent protein kinases and cell cycle regulation in biology and disease

Cyclin Dependent Kinases (CDKs) are closely connected to the regulation of cell cycle progression, having been first identified as the kinases able to drive cell division. In reality, the human genome contains 20 different CDKs, which can be divided in at least three different sub-family with different functions, mechanisms of regulation, expression patterns and subcellular localization. Most of these kinases play fundamental roles the normal physiology of eucaryotic cells; therefore, their deregulation is associated with the onset and/or progression of multiple human disease including but not limited to neoplastic and neurodegenerative conditions. Here, we describe the functions of CDKs, categorized into the three main functional groups in which they are classified, highlighting the most relevant pathways that drive their expression and functions. We then discuss the potential roles and deregulation of CDKs in human pathologies, with a particular focus on cancer, the human disease in which CDKs have been most extensively studied and explored as therapeutic targets. Finally, we discuss how CDKs inhibitors have become standard therapies in selected human cancers and propose novel ways of investigation to export their targeting from cancer to other relevant chronic diseases. We hope that the effort we made in collecting all available information on both the prominent and lesser-known CDK family members will help in identify and develop novel areas of research to improve the lives of patients affected by debilitating chronic diseases.

BMSC derived EVs inhibit colorectal Cancer progression by transporting MAGI2-AS3 or something similar

In this study, we investigated the molecular mechanisms underlying the impact of extracellular vesicles (EVs) derived from bone marrow stromal cells (BMSCs) on colorectal cancer (CRC) development. The focus was on the role of MAGI2-AS3, delivered by BMSC-EVs, in regulating USP6NL DNA methylation-mediated MYC protein translation modification to promote CDK2 downregulation. Utilizing bioinformatics analysis, we identified significant enrichment of MAGI2-AS3 related to copper-induced cell death in CRC. In vitro experiments demonstrated the downregulation of MAGI2-AS3 in CRC cells, and BMSC-EVs were found to deliver MAGI2-AS3 to inhibit CRC cell proliferation, migration, and invasion. Further exploration revealed that MAGI2-AS3 suppressed MYC protein translation modification by regulating USP6NL DNA methylation, leading to CDK2 downregulation and prevention of colorectal cancer. Overexpression of MYC reversed the functional effects of BMSC-EVs-MAGI2-AS3. In vivo experiments validated the inhibitory impact of BMSC-EVs-MAGI2-AS3 on CRC tumorigenicity by promoting CDK2 downregulation through USP6NL DNA methylation-mediated MYC protein translation modification. Overall, BMSC-EVs-MAGI2-AS3 may serve as a potential intervention to prevent CRC occurrence by modulating key molecular pathways.

Construction of a circadian rhythm-relevant gene signature for hepatocellular carcinoma prognosis, immunotherapy and chemosensitivity prediction

Aims

This study explored the molecular and biologic mechanisms underlying the association between circadian rhythm disorders (CRD) and increased risk for hepatocellular carcinoma (HCC).

Background

CRD are linked to increased risk for HCC, but the molecular and biologic mechanisms underlying this association are limited.ObjectiveThe study constructed and validated a CRD related gene model as an independent prognostic factor for HCC, providing insight into the molecular mechanisms linking CRD to increased HCC risk and identifying potential indicators for the efficacy of immunotherapy and anticancer drugs. This helps provide important clues for personalized treatment strategies for HCC patients.

Methods

Gene sets correlated with circadian rhythm were obtained from the Molecular Signatures Database (MSigDB) to intersect with differentially expressed genes (DEGs) between tumor samples and control samples in The Cancer Genome Atlas (TCGA) and HCCDB18 from Hepatocellular Carcinoma Cell DataBase (HCCDB). The CRD related gene model was developed by univariate Cox and stepwise multivariate analysis. Immune checkpoint blockade (ICB) therapy and anticancer drugs were analyzed using the tumor immune dysfunction and exclusion (TIDE) and pRRophetic, respectively. Seurat determined the cell type of HCC by analyzing single-cell data, and malignant cells were identified using Copykat. To detect the mRNA levels of genes in the CRD related gene model, quantitative real-time polymerase chain reaction (qRT-PCR) was carried out.

Results

The activity of circadian rhythm in HCC tissue was significantly lower than that in control tissue. Subsequently, EZH2, IMPDH2, TYMS and SERPINE1 were selected to construct the CRD related gene model, which was an independent factor for HCC prognosis. Notably, low-risk patients had lower levels of immune cell infiltration and lower TIDE scores compared to high-risk patients with HCC, indicating that patients with a low risk may derive more benefit from immunotherapy. IMPDH2, TYMS and SERPINE1 expressed significantly higher in malignant cells than in benign epithelial cells.

Conclusions

This study presents a CRD related gene model to reveal the molecular perspective of the dependent mechanism of the association between CRD and cancer, which provides a potential indicator for understanding the preclinical efficacy of ICB and anticancer drugs.

Myeloid-intrinsic cell cycle-related kinase drives immunosuppression to promote tumorigenesis

Massive expansion of immature and suppressive myeloid cells is a common feature of malignant solid tumors. Over-expression of cyclin-dependent kinase 20, also known as cell cycle-related kinase (CCRK), in hepatocellular carcinoma (HCC) correlates with reduced patient survival and low immunotherapy responsiveness. Beyond tumor-intrinsic oncogenicity, here we demonstrated that CCRK is upregulated in myeloid cells in tumor-bearing mice and in patients with HCC. Intratumoral injection of Ccrk-knockdown myeloid-derived suppressor cells (MDSCs) increased tumor-infiltrating CD8+T cells and suppressed HCC tumorigenicity. Using an indel mutant transgenic model, we showed that Ccrk inactivation in myeloid cells conferred a mature phenotype with elevated IL-12 production, driving Th1 responses and CD8+T cell cytotoxicity to reduce orthotopic tumor growth and prolong survival. Mechanistically, CCRK activates STAT3/E4BP4 signaling in MDSCs to acquire immunosuppressive activity through transcriptional IL-10 induction and IL-12 suppression. Taken together, our findings unravel mechanistic insights into MDSC-mediated immunosuppression and offer a therapeutic kinase-target for cancer immunotherapy.

Cyclin-dependent kinases: Masters of the eukaryotic universe

A family of structurally related cyclin-dependent protein kinases (CDKs) drives many aspects of eukaryotic cell function. Much of the literature in this area has considered individual members of this family to act primarily either as regulators of the cell cycle, the context in which CDKs were first discovered, or as regulators of transcription. Until recently, CDK7 was the only clear example of a CDK that functions in both processes. However, new data points to several "cell-cycle" CDKs having important roles in transcription and some "transcriptional" CDKs having cell cycle-related targets. For example, novel functions in transcription have been demonstrated for the archetypal cell cycle regulator CDK1. The increasing evidence of the overlap between these two CDK types suggests that they might play a critical role in coordinating the two processes. Here we review the canonical functions of cell-cycle and transcriptional CDKs, and provide an update on how these kinases collaborate to perform important cellular functions. We also provide a brief overview of how dysregulation of CDKs contributes to carcinogenesis, and possible treatment avenues. This article is categorized under: RNA Interactions with Proteins and Other Molecules > RNA-Protein Complexes RNA Processing > 3' End Processing RNA Processing > Splicing Regulation/Alternative Splicing.

EZH2 in hepatocellular carcinoma: progression, immunity, and potential targeting therapies

Hepatocellular carcinoma (HCC) is the leading cause of cancer-related death. The accumulation of genetic and epigenetic changes is closely related to the occurrence and development of HCC. Enhancer of zeste homolog 2 (EZH2, a histone methyltransferase) is suggested to be one of the principal factors that mediates oncogenesis by acting as a driver of epigenetic alternation. Recent studies show that EZH2 is widely involved in proliferation and metastasis of HCC cells. In this review, the functions of EZH2 in HCC progression, the role of EZH2 in tumor immunity and the application of EZH2-related inhibitors in HCC therapy are summarized.

Primary cilia shape hallmarks of health and aging

Primary cilia are specialized organelles that sense changes in extracellular milieu, and their malfunction is responsible for several disorders (ciliopathies). Increasing evidence shows that primary cilia regulate tissue and cellular aging related features, which led us to review the evidence on their role in potentiating and/or accelerating the aging process. Primary cilia malfunction is associated with some age-related disorders, from cancer to neurodegenerative and metabolic disorders. However, there is limited understanding of molecular pathways underlying primary cilia dysfunction, resulting in scarce ciliary-targeted therapies available. Here, we discuss the findings on primary cilia dysfunction as modulators of the health and aging hallmarks, and the pertinence of ciliary pharmacological targeting to promote healthy aging or treat age-related diseases.

AlphaFold2 and its applications in the fields of biology and medicine

AlphaFold2 (AF2) is an artificial intelligence (AI) system developed by DeepMind that can predict three-dimensional (3D) structures of proteins from amino acid sequences with atomic-level accuracy. Protein structure prediction is one of the most challenging problems in computational biology and chemistry, and has puzzled scientists for 50 years. The advent of AF2 presents an unprecedented progress in protein structure prediction and has attracted much attention. Subsequent release of structures of more than 200 million proteins predicted by AF2 further aroused great enthusiasm in the science community, especially in the fields of biology and medicine. AF2 is thought to have a significant impact on structural biology and research areas that need protein structure information, such as drug discovery, protein design, prediction of protein function, et al. Though the time is not long since AF2 was developed, there are already quite a few application studies of AF2 in the fields of biology and medicine, with many of them having preliminarily proved the potential of AF2. To better understand AF2 and promote its applications, we will in this article summarize the principle and system architecture of AF2 as well as the recipe of its success, and particularly focus on reviewing its applications in the fields of biology and medicine. Limitations of current AF2 prediction will also be discussed.

AlphaFold accelerates artificial intelligence powered drug discovery: efficient discovery of a novel CDK20 small molecule inhibitor

The application of artificial intelligence (AI) has been considered a revolutionary change in drug discovery and development. In 2020, the AlphaFold computer program predicted protein structures for the whole human genome, which has been considered a remarkable breakthrough in both AI applications and structural biology. Despite the varying confidence levels, these predicted structures could still significantly contribute to structure-based drug design of novel targets, especially the ones with no or limited structural information. In this work, we successfully applied AlphaFold to our end-to-end AI-powered drug discovery engines, including a biocomputational platform PandaOmics and a generative chemistry platform Chemistry42. A novel hit molecule against a novel target without an experimental structure was identified, starting from target selection towards hit identification, in a cost- and time-efficient manner. PandaOmics provided the protein of interest for the treatment of hepatocellular carcinoma (HCC) and Chemistry42 generated the molecules based on the structure predicted by AlphaFold, and the selected molecules were synthesized and tested in biological assays. Through this approach, we identified a small molecule hit compound for cyclin-dependent kinase 20 (CDK20) with a binding constant Kd value of 9.2 ± 0.5 μM (n = 3) within 30 days from target selection and after only synthesizing 7 compounds. Based on the available data, a second round of AI-powered compound generation was conducted and through this, a more potent hit molecule, ISM042-2-048, was discovered with an average Kd value of 566.7 ± 256.2 nM (n = 3). Compound ISM042-2-048 also showed good CDK20 inhibitory activity with an IC50 value of 33.4 ± 22.6 nM (n = 3). In addition, ISM042-2-048 demonstrated selective anti-proliferation activity in an HCC cell line with CDK20 overexpression, Huh7, with an IC50 of 208.7 ± 3.3 nM, compared to a counter screen cell line HEK293 (IC50 = 1706.7 ± 670.0 nM). This work is the first demonstration of applying AlphaFold to the hit identification process in drug discovery.

The role of AccCDK20 and AccCDKN1 from Apis cerana cerana in development and response to pesticide and heavy metal toxicity

Apis cerana cerana is a native bee species in China and plays a key role in agricultural production and ecological balance. However, the growth and development of Apis cerana cerana has not been smooth, and pesticide and heavy metal stress are key factors that have forced a dramatic decline in population size. This study was performed with the objective of investigating the role of AccCDK20 and AccCDKN1 in honey bee resistance to pesticide and heavy metal stress. RT-qPCR analysis revealed that AccCDK20 transcript levels were highest in brown-eyed pupae and AccCDKN1 transcript levels were highest in 1-day-old worker bees. In different tissues and body parts of adult bees, AccCDK20 transcript levels were highest in the head, and AccCDKN1 transcript levels were highest in the thorax. It was further observed that environmental stress can affect the transcript levels of the AccCDK20 and AccCDKN1 genes. Silencing of the AccCDK20 and AccCDKN1 genes resulted in altered activities of antioxidant-related genes and antioxidant-related enzymes. AccCDK20 and AccCDKN1 transcript levels were upregulated under glyphosate stress, and silencing of the genes resulted in reduced resistance to glyphosate and greatly increased mortality in Apis cerana cerana. In addition, gene function was verified by in vitro repression assays. Overexpression of the AccCDK20 and AccCDKN1 proteins in E. coli cells increased the resistance to ROS damage induced by CHP. In conclusion, AccCDK20 and AccCDKN1 play an indispensable role in honey bee resistance to pesticide and heavy metal stress.

Effects of the Targeted Regulation of CCRK by miR-335-5p on the Proliferation and Tumorigenicity of Human Renal Carcinoma Cells

Cell cycle-related kinase (CCRK) is most closely related to cyclin-dependent protein kinase, which may activate cyclin-dependent kinase 2 and is associated with the growth of human cancer cells. However, the expression and function of CCRK in the pathogenesis of clear cell renal cell cancer (ccRCC) are unclear. Herein, this research aimed to explore the potential mechanism of the targeted regulation of CCRK by miR-335-5p on the proliferation and tumorigenicity of human ccRCC cells. The results showed that CCRK was significantly overexpressed in ccRCC tissues and cells, and knockdown of the CCRK expression by shRNA inhibited cell proliferation in vitro and in vivo and enhanced cell apoptosis in vitro, which indicated that CCRK could be a potential target for antitumour drugs in the treatment of ccRCC. Moreover, miR-335-5p was found to bind directly to the 3′ untranslated region of CCRK, was expressed at markedly low levels in ccRCC cells, and was closely associated with the tumour stage. The overexpression of CCRK partially reversed the inhibitory effects of miR-335-5p on the cell growth of ccRCC, which implied that miR-335-5p could serve as a promising tumour inhibitor for ccRCC. In summary, CCRK could serve as an alternative antitumour drug target, and miR-335-5p could be a promising therapeutic tumour inhibitor for ccRCC treatment.

Cyclin-dependent kinases as potential targets for colorectal cancer: past, present and future

Colorectal cancer (CRC) is a common cancer in the world and its prevalence is increasing in developing countries. Deregulated cell cycle traverse is a hallmark of malignant transformation and is often observed in CRC as a result of imprecise activity of cell cycle regulatory components, viz. cyclins and cyclin-dependent kinases (CDKs). Apart from cell cycle regulation, some CDKs also regulate processes such as transcription and have also been shown to be involved in colorectal carcinogenesis. This article aims to review cyclin-dependent kinases as potential targets for CRC. Furthermore, therapeutic candidates to target CDKs are also discussed.

RNA-binding protein MEX3A controls G1/S transition via regulating the RB/E2F pathway in clear cell renal cell carcinoma

MEX3A is an RNA-binding protein that mediates mRNA decay through binding to 3′ untranslated regions. However, its role and mechanism in clear cell renal cell carcinoma remain unknown. In this study, we found that MEX3A expression was transcriptionally activated by ETS1 and upregulated in clear cell renal cell carcinoma. Silencing MEX3A markedly reduced clear cell renal cell carcinoma cell proliferation in vitro and in vivo. Inhibiting MEX3A induced G1/S cell-cycle arrest. Gene set enrichment analysis revealed that E2F targets are the central downstream pathways of MEX3A. To identify MEX3A targets, systematic screening using enhanced cross-linking and immunoprecipitation sequencing, and RNA-immunoprecipitation sequencing assays were performed. A network of 4,000 genes was identified as potential targets of MEX3A. Gene ontology analysis of upregulated genes bound by MEX3A indicated that negative regulation of the cell proliferation pathway was highly enriched. Further assays indicated that MEX3A bound to the CDKN2B 3′ untranslated region, promoting its mRNA degradation. This leads to decreased levels of CDKN2B and an uncontrolled cell cycle in clear cell renal cell carcinoma, which was confirmed by rescue experiments. Our findings revealed that MEX3A acts as a post-transcriptional regulator of abnormal cell-cycle progression in clear cell renal cell carcinoma.

EZH2 expression is associated with inferior overall survival in mantle cell lymphoma

Enhancer of zeste homolog 2 (EZH2) is a catalytic component of the polycomb repressive complex 2 (PRC2) which reduces gene expression via trimethylation of a lysine residue of histone 3 (H3K27me3). Expression of EZH2 has not been assessed systematically in mantle cell lymphoma (MCL). Expression of EZH2 was assessed by immunohistochemistry in 166 patients with MCL. We also assessed other PRC2 components and H3K27me3. Fifty-seven (38%) of MCL patients were positive for EZH2 using 40% cutoff. EZH2 expression was associated with aggressive histologic variants (65% vs. 29%, p < 0.001), high Ki-67 proliferation rate (median, 72% vs. 19%, p < 0.001), and p53 overexpression (43% vs. 2%, p < 0.001). EZH2 expression did not correlate with expression of other PRC2 components (EED and SUZ12), H3K27me3, MHC-I, and MHC-II. Patients with EZH2 expression (EZH2+) had a poorer overall survival (OS) compared with patients without EZH2 expression (EZH2-) (median OS: 3.9 years versus 9.4 years, respectively, p < 0.001). EZH2 expression also predicted a poorer prognosis in MCL patients with classic histology (median OS, 4.6 years for EZH2+ and 9.6 years for EZH2-negative, respectively, p < 0.001) as well as aggressive histology (median OS, 3.7 years for EZH2+ and 7.9 years for EZH2-negative, respectively, p = 0.046). However, EZH2 expression did not independently correlate with overall survival in a multivariate analysis. Gene expression analysis and pathway enrichment analysis demonstrated a significant enrichment in cell cycle and mitotic transition pathways in MCL with EZH2 expression. EZH2 expression detected by immunohistochemistry is present in 38% of MCL cases and it is associated with high proliferation rate, p53 overexpression, aggressive histologic variants, and poorer OS. Based on gene expression profiling data, EZH2 expression could potentiate cell cycle machinery in MCL. These data suggest that assessment of EZH2 expression could be useful to stratify MCL patients into low- and high-risk groups.

Cilia kinases in skeletal development and homeostasis

Primary cilia are dynamic compartments that regulate multiple aspects of cellular signaling. The production, maintenance, and function of cilia involve more than 1000 genes in mammals, and their mutations disrupt the ciliary signaling which manifests in a plethora of pathological conditions-the ciliopathies. Skeletal ciliopathies are genetic disorders affecting the development and homeostasis of the skeleton, and encompass a broad spectrum of pathologies ranging from isolated polydactyly to lethal syndromic dysplasias. The recent advances in forward genetics allowed for the identification of novel regulators of skeletogenesis, and revealed a growing list of ciliary proteins that are critical for signaling pathways implicated in bone physiology. Among these, a group of protein kinases involved in cilia assembly, maintenance, signaling, and disassembly has emerged. In this review, we summarize the functions of cilia kinases in skeletal development and disease, and discuss the available and upcoming treatment options.

Primary Cilia-Related Pathways Moderate the Development and Therapy Resistance of Glioblastoma

As microtubule-based structures, primary cilia are typically present on the cells during the G0 or G1-S/G2 phase of the cell cycle and are closely related to the development of the central nervous system. The presence or absence of this special organelle may regulate the central nervous system tumorigenesis (e.g., glioblastoma) and several degenerative diseases. Additionally, the development of primary cilia can be regulated by several pathways. Conversely, primary cilia are able to regulate a few signaling transduction pathways. Therefore, development of the central nervous system tumors in conjunction with abnormal cilia can be regulated by up- or downregulation of the pathways related to cilia and ciliogenesis. Here, we review some pathways related to ciliogenesis and tumorigenesis, aiming to provide a potential target for developing new therapies at genetic and molecular levels.

CIRCNV: Detection of CNVs Based on a Circular Profile of Read Depth from Sequencing Data

Simple Summary

In this study, we propose a copy number variation (CNV) detection method called CIRCNV, which is based on a circular profile of the read depth from sequencing data. The proposed method is an extended version of our previously developed method CNV-LOF. The main difference of CIRCNV from CNV-LOF lies in its two new features: (1) it transfers the read depth profile from a line shape to a circular shape via a polar coordinate transformation to generate a meaningful two-dimensional dataset for CNV analysis and promote fairness between the ends and middle part of the genome, and (2) it performs two rounds of CNV declaration via estimating tumor purity and recovering the truth circular RD profile. We test and evaluate the performance of CIRCNV via conducting simulation studies and real sequencing tumor sample applications. The experimental results show that CIRCNV outperforms peer methods with respect to sensitivity, precision, and the F1-score. The experiments prove that the proposed method is a reliable and effective tool in the field of variation analysis of tumor genomes.

Abstract

Copy number variation (CNV) is a common type of structural variation in the human genome. Accurate detection of CNVs from tumor genomes can provide crucial information for the study of tumor genesis and cancer precision diagnosis. However, the contamination of normal genomes in tumor genomes and the crude profiles of the read depth make such a task difficult. In this paper, we propose an alternative approach, called CIRCNV, for the detection of CNVs from sequencing data. CIRCNV is an extension of our previously developed method CNV-LOF, which uses local outlier factors to predict CNVs. Comparatively, CIRCNV can be performed on individual tumor samples and has the following two new features: (1) it transfers the read depth profile from a line shape to a circular shape via a polar coordinate transformation, in order to improve the efficiency of the read depth (RD) profile for the detection of CNVs; and (2) it performs a second round of CNV declaration based on the truth circular RD profile, which is recovered by estimating tumor purity. We test and validate the performance of CIRCNV based on simulation and real sequencing data and perform comparisons with several peer methods. The results demonstrate that CIRCNV can obtain superior performance in terms of sensitivity and precision. We expect that our proposed method will be a supplement to existing methods and become a routine tool in the field of variation analysis of tumor genomes.

Tenacissoside G synergistically potentiates inhibitory effects of 5-fluorouracil to human colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is one of the most malignant tumors worldwide with poor prognosis and low survival rate. Since the clinical efficacy of the commonly used 5-fluorouracil (5-FU) based chemotherapy in CRC patients is limited because of its intolerable adverse effects, there is an urgent need to explore agents that can enhance the anti-cancer activity of 5-FU, reduce adverse effects and prevent resistance.

PURPOSE

This study aims to investigate Tenacissoside G (TG)'s synergistic potentiation with 5-FU in inhibitory activity to colorectal cancer cells.

METHODS

The anti-proliferation effect of TG on 5 colorectal cancer cell lines was assessed by CCK-8 assay. The isobologram analysis and combination index methods were used to detect the synergistic effect of TG and 5-FU by the CompuSyn software using the T.C. Chou Method. The effects of TG/5-FU combination on cell cycle distribution and apoptosis induction were detected by flow cytometry. DNA damage degrees of cells treated with TG, 5-FU and their combination were evaluated by the alkaline comet assay. Protein expression regulated by the TG/5-FU combination was investigated by western blotting. Furthermore, a xenograft mouse model was established to investigate the synergistic anti-tumor effect in vivo.

RESULTS

In this work, we observed a dose-dependent growth inhibitory activity and cell cycle arrest induction of TG, a monomeric substance originated from Marsdenia tenacissima (Roxb.) Wight et Arn, in colorectal cancer cells. It was found that TG potentiated the anticancer effects of 5-FU with a synergism for the first time. And the co-treatment effects were also validated by in vivo experiments. The underlying mechanisms involved in the synergistic effects were probably included: (1) increased activation of caspase cascade; (2) enhancement of DNA damage degree and (3) induction of p53 phosphorylation at Serine 46.

CONCLUSION

TG potentiated 5-FU's inhibitory activity to human colorectal cancer through arresting cell cycle progression and inducing p53-mediated apoptosis, which may present a novel strategy in CRC therapies and contribute to the optimizing clinical application of 5-FU.

Liver Immune Microenvironment and Metastasis from Colorectal Cancer-Pathogenesis and Therapeutic Perspectives

A drastic difference exists between the 5-year survival rates of colorectal cancer patients with localized cancer and distal organ metastasis. The liver is the most favorable organ for cancer metastases from the colorectum. Beyond the liver-colon anatomic relationship, emerging evidence highlights the impact of liver immune microenvironment on colorectal liver metastasis. Prior to cancer cell dissemination, hepatocytes secrete multiple factors to recruit or activate immune cells and stromal cells in the liver to form a favorable premetastatic niche. The liver-resident cells including Kupffer cells, hepatic stellate cells, and liver-sinusoidal endothelial cells are co-opted by the recruited cells, such as myeloid-derived suppressor cells and tumor-associated macrophages, to establish an immunosuppressive liver microenvironment suitable for tumor cell colonization and outgrowth. Current treatments including radical surgery, systemic therapy, and localized therapy have only achieved good clinical outcomes in a minority of colorectal cancer patients with liver metastasis, which is further hampered by high recurrence rate. Better understanding of the mechanisms governing the metastasis-prone liver immune microenvironment should open new immuno-oncology avenues for liver metastasis intervention.

Role of Epigenetic Regulation in Plasticity of Tumor Immune Microenvironment

The tumor immune microenvironment (TIME), an immunosuppressive niche, plays a pivotal role in contributing to the development, progression, and immune escape of various types of cancer. Compelling evidence highlights the feasibility of cancer therapy targeting the plasticity of TIME as a strategy to retrain the immunosuppressive immune cells, including innate immune cells and T cells. Epigenetic alterations, such as DNA methylation, histone post-translational modifications, and noncoding RNA-mediated regulation, regulate the expression of many human genes and have been reported to be accurate in the reprogramming of TIME according to vast majority of published results. Recently, mounting evidence has shown that the gut microbiome can also influence the colorectal cancer and even extraintestinal tumors via metabolites or microbiota-derived molecules. A tumor is a kind of heterogeneous disease with specificity in time and space, which is not only dependent on genetic regulation, but also regulated by epigenetics. This review summarizes the reprogramming of immune cells by epigenetic modifications in TIME and surveys the recent progress in epigenetic-based cancer clinical therapeutic approaches. We also discuss the ongoing studies and future areas of research that benefits to cancer eradication.

The Role of Cell Cycle Regulators in Cell Survival-Dual Functions of Cyclin-Dependent Kinase 20 and p21Cip1/Waf1

The mammalian cell cycle is important in controlling normal cell proliferation and the development of various diseases. Cell cycle checkpoints are well regulated by both activators and inhibitors to avoid cell growth disorder and cancerogenesis. Cyclin dependent kinase 20 (CDK20) and p21^Cip1/Waf1 are widely recognized as key regulators of cell cycle checkpoints controlling cell proliferation/growth and involving in developing multiple cancers. Emerging evidence demonstrates that these two cell cycle regulators also play an essential role in promoting cell survival independent of the cell cycle, particularly in those cells with a limited capability of proliferation, such as cardiomyocytes. These findings bring new insights into understanding cytoprotection in these tissues. Here, we summarize the new progress of the studies on these two molecules in regulating cell cycle/growth, and their new roles in cell survival by inhibiting various cell death mechanisms. We also outline their potential implications in cancerogenesis and protection in heart diseases. This information renews the knowledge in molecular natures and cellular functions of these regulators, leading to a better understanding of the pathogenesis of the associated diseases and the discovery of new therapeutic strategies.

HOXC10 promotes tumour metastasis by regulating the EMT-related gene Slug in ovarian cancer

The mortality rate of ovarian cancer is the highest among gynaecological cancers, primarily due to metastatic symptoms. Recent studies have shown that HOX genes are crucial in tumour progression, but the underlying mechanisms remain unclear. Here, HOXC10 expression was examined in ovarian cancer tissues. The function of HOXC10 in ovarian cancer metastasis was investigated in vitroand via intraperitoneal injection in vivo. A total of 158 ovarian cancer patients with adequate records were enrolled for analysis. HOXC10 was associated with metastasis and poor prognosis in ovarian cancer. In vitro, HOXC10 overexpression promoted ovarian cancer cell migration. Moreover, HOXC10 positively regulated Slug expression, altering the migration ability of cancer cells. Furthermore, our study showed that miR-222-3p was a suppressor of HOXC10. In vivo, a decrease in hepatic metastasis was seen in xenograft mice harbouring tumours with stable HOXC10 overexpression after miR-222-3p agomir (an overexpression reagent) injection. This study provides the first evidence that HOXC10 promotes ovarian cancer metastasis by regulating the transcription of the EMT-related gene Slug. Moreover, we found that HOXC10 is regulated by miR-222-3p. These data highlight the crucial role of HOXC10 in enhancing ovarian cancer metastasis and may provide a therapeutic target for ovarian cancer.

Cell cycle-related kinase reprograms the liver immune microenvironment to promote cancer metastasis

The liver is an immunologically tolerant organ and a common metastatic site of multiple cancer types. Although a role for cancer cell invasion programs has been well characterized, whether and how liver-intrinsic factors drive metastatic spread is incompletely understood. Here, we show that aberrantly activated hepatocyte-intrinsic cell cycle-related kinase (CCRK) signaling in chronic liver diseases is critical for cancer metastasis by reprogramming an immunosuppressive microenvironment. Using an inducible liver-specific transgenic model, we found that CCRK overexpression dramatically increased both B16F10 melanoma and MC38 colorectal cancer (CRC) metastasis to the liver, which was highly infiltrated by polymorphonuclear-myeloid-derived suppressor cells (PMN-MDSCs) and lacking natural killer T (NKT) cells. Depletion of PMN-MDSCs in CCRK transgenic mice restored NKT cell levels and their interferon gamma production and reduced liver metastasis to 2.7% and 0.7% (metastatic tumor weights) in the melanoma and CRC models, respectively. Mechanistically, CCRK activated nuclear factor-kappa B (NF-κB) signaling to increase the PMN-MDSC-trafficking chemokine C-X-C motif ligand 1 (CXCL1), which was positively correlated with liver-infiltrating PMN-MDSC levels in CCRK transgenic mice. Accordingly, CRC liver metastasis patients exhibited hyperactivation of hepatic CCRK/NF-κB/CXCL1 signaling, which was associated with accumulation of PMN-MDSCs and paucity of NKT cells compared to healthy liver transplantation donors. In summary, this study demonstrates that immunosuppressive reprogramming by hepatic CCRK signaling undermines antimetastatic immunosurveillance. Our findings offer new mechanistic insights and therapeutic targets for liver metastasis intervention.

circ_0084927 promotes cervical carcinogenesis by sponging miR-1179 that suppresses CDK2, a cell cycle-related gene

Background

Cervical cancer (CC) is a malignant tumor found in the lowermost part of the womb. Evolving studies on CC have reported that circRNA plays a crucial role in CC progression. In this study, we investigated the main function of a novel circRNA, circ_0084927, and its regulatory network in CC development.

Methods

qRT-PCR was applied to evaluate the expression of circ_0084927, miR-1179, and CDK2 mRNA in CC tissues and cells. Dual-luciferase reporting experiments and RNA immunoprecipitation (RIP) assay were conducted to validate the target relationship of miR-1179 with circ_0084927 and CDK2 mRNA. CCK-8 and BrdU assays were also used to evaluate CC cell proliferation. The adhesion and apoptosis phenotypes of CC cells were measured using cell–matrix adhesion and caspase 3 activation assay. Flow cytometry was also employed to detect the CC cell cycle.

Results

Our results indicated that circ_0084927 was up-regulated in CC tissues and cells. Findings also revealed that circ_0084927 silence inhibited CC cell proliferation and adhesion while facilitating apoptosis and triggering cell cycle arrest. However, miR-1179 down-regulation appeared in CC tissues. Apart from observing that circ_0084927 abolished miR-1179’s inhibitory effects on cell proliferation and adhesion, it was found that CDK2 was up-regulated in CC tissues and was instrumental in cancer promotion. Also observed was that miR-1179 directly targeted CDK2, thereby inhibiting CDK2’s promotion on the malignant phenotypes of CC cells. Lastly, results indicated that circ_0084927 revoked the inhibitory effect of miR-1179 on CDK2 by sponging miR-1179.

Conclusion

circ_0084927 promoted cervical carcinogenesis by sequestering miR-1179, which directly targeted CDK2. Our results also provided novel candidate targets for CC treatment in that it revealed the circ_0084927/miR-1179/CDK2 regulatory network that strengthened CC aggressiveness.

The Differential Effect of Carbon Dots on Gene Expression and DNA Methylation of Human Embryonic Lung Fibroblasts as a Function of Surface Charge and Dose

This study presents a toxicological evaluation of two types of carbon dots (CD), similar in size (<10 nm) but differing in surface charge. Whole-genome mRNA and miRNA expression (RNAseq), as well as gene-specific DNA methylation changes, were analyzed in human embryonic lung fibroblasts (HEL 12469) after 4 h and 24 h exposure to concentrations of 10 and 50 µg/mL (for positive charged CD; pCD) or 10 and 100 µg/mL (for negative charged CD, nCD). The results showed a distinct response for the tested nanomaterials (NMs). The exposure to pCD induced the expression of a substantially lower number of mRNAs than those to nCD, with few commonly differentially expressed genes between the two CDs. For both CDs, the number of deregulated mRNAs increased with the dose and exposure time. The pathway analysis revealed a deregulation of processes associated with immune response, tumorigenesis and cell cycle regulation, after exposure to pCD. For nCD treatment, pathways relating to cell proliferation, apoptosis, oxidative stress, gene expression, and cycle regulation were detected. The expression of miRNAs followed a similar pattern: more pronounced changes after nCD exposure and few commonly differentially expressed miRNAs between the two CDs. For both CDs the pathway analysis based on miRNA-mRNA interactions, showed a deregulation of cancer-related pathways, immune processes and processes involved in extracellular matrix interactions. DNA methylation was not affected by exposure to any of the two CDs. In summary, although the tested CDs induced distinct responses on the level of mRNA and miRNA expression, pathway analyses revealed a potential common biological impact of both NMs independent of their surface charge.

CDKs in Sarcoma: Mediators of Disease and Emerging Therapeutic Targets

Sarcomas represent one of the most challenging tumor types to treat due to their diverse nature and our incomplete understanding of their underlying biology. Recent work suggests cyclin-dependent kinase (CDK) pathway activation is a powerful driver of sarcomagenesis. CDK proteins participate in numerous cellular processes required for normal cell function, but their dysregulation is a hallmark of many pathologies including cancer. The contributions and significance of aberrant CDK activity to sarcoma development, however, is only partly understood. Here, we describe what is known about CDK-related alterations in the most common subtypes of sarcoma and highlight areas that warrant further investigation. As disruptions in CDK pathways appear in most, if not all, subtypes of sarcoma, we discuss the history and value of pharmacologically targeting CDKs to combat these tumors. The goals of this review are to (1) assess the prevalence and importance of CDK pathway alterations in sarcomas, (2) highlight the gap in knowledge for certain CDKs in these tumors, and (3) provide insight into studies focused on CDK inhibition for sarcoma treatment. Overall, growing evidence demonstrates a crucial role for activated CDKs in sarcoma development and as important targets for sarcoma therapy.

CDC27 Promotes Tumor Progression and Affects PD-L1 Expression in T-Cell Lymphoblastic Lymphoma

T-lymphoblastic lymphoma (T-LBL) is a rare hematological malignancy with highly aggressive, unique clinical manifestations, and poor prognosis. Cell division cycle 27 (CDC27) was previously reported to be a significant subunit of the anaphase-promoting complex/cyclosome. However, the specific functions and relevant mechanisms of CDC27 in T-LBL remain unknown. Through immunohistochemistry staining, we identified that CDC27 was overexpressed in T-LBL tissues and related to tumor progression and poor survival. Functional experiments demonstrated that CDC27 promoted proliferation in vivo and in vitro. Further experiment suggested the role of CDC27 in facilitating G1/S transition and promoting the expression of Cyclin D1 and CDK4. Then the effect of CDC27 in inhibiting apoptosis was also identified. Furthermore, we found a positive correlation between the expression of CDC27 and Programmed death ligand-1 (PD-L1) by immunohistochemistry staining. The interaction between CDC27 and PD-L1 was also proved by western blot, luciferase gene reporter assay and immunofluorescence. Taken together, our results showed that CDC27 contributes to T-LBL progression and there is a positive correlation between PD-L1 and CDC27, which offers novel perspectives for future studies on targeting CDC27 in T-LBL.

Zinc finger of the cerebellum 5 promotes colorectal cancer cell proliferation and cell cycle progression through enhanced CDK1/CDC25c signaling

Introduction

Colorectal cancer (CRC), mostly caused by external or environmental factors, is the third most common and lethal cancer worldwide. Although a large number of investigations have been carried out to reveal the evolution of CRC, the underlying mechanisms of CRC remain unclear.

Material and methods

Expression of zinc finger of the cerebellum 5 (ZIC5) in CRC tissues and cell models was measured by qRT-PCR and IHC. Cell transfection was carried out for ZIC5 overexpression or knockdown. The MTT assay was applied to examine the capacity of glioma cell proliferation. Wound healing assay and tumor invasion assay were used to test the capacity of glioma cell migration and invasion respectively. Cell cycle analysis and western blot were used to verify the apoptosis rates of CRC cells upon ZIC5 overexpression or downregulation. A further tumor Xenograft study was used to examine the effects of ZIC5 on tumor malignancy in vivo.

Results

Cell models using HCT116 and SW620 cells were established to study the ZIC5 function upon ZIC5 overexpression of knockdown. Consistently, we discovered that ZIC5 also significantly increased in Chinese CRC patients. In addition, ZIC5 promoted CRC cell proliferation through increasing the proportion of cells maintained in the S phase. ZIC5 overexpression facilitated the capacity of CRC cell migration and invasion. Inhibition of ZIC5 mitigated such malignant effects.

Conclusions

Collectively, investigations of the ZIC5 in CRC provided a new insight into CRC diagnosis, treatment, prognosis and next-step translational therapeutic developments from bench to clinic.

From bench to bed: the tumor immune microenvironment and current immunotherapeutic strategies for hepatocellular carcinoma

Hepatocellular carcinoma (HCC) ranks the most common primary liver malignancy and the third leading cause of tumor-related mortality worldwide. Unfortunately, despite advances in HCC treatment, less than 40% of HCC patients are eligible for potentially curative therapies. Recently, cancer immunotherapy has emerged as one of the most promising approaches for cancer treatment. It has been proven therapeutically effective in many types of solid tumors, such as non-small cell lung cancer and melanoma. As an inflammation-associated tumor, it's well-evidenced that the immunosuppressive microenvironment of HCC can promote immune tolerance and evasion by various mechanisms. Triggering more vigorous HCC-specific immune response represents a novel strategy for its management. Pre-clinical and clinical investigations have revealed that various immunotherapies might extend current options for needed HCC treatment. In this review, we provide the recent progress on HCC immunology from both basic and clinical perspectives, and discuss potential advances and challenges of immunotherapy in HCC.

Cyclin dependent kinase (CDK) inhibitors as anticancer drugs: Recent advances (2015-2019)

Sustained proliferative capacity and gene dysregulation are hallmarks of cancer. In mammalian cells, cyclin-dependent kinases (CDKs) control critical cell cycle checkpoints and key transcriptional events in response to extracellular and intracellular signals leading to proliferation. Significant clinical activity for the treatment of hormone receptor positive metastatic breast cancer has been demonstrated by palbociclib, ribociclib and abemaciclib, dual CDK4/6 inhibitors recently FDA-approved. SY-1365, a CDK7 inhibitor has shown initial encouraging data in phase I for solid tumors treatment. These results have rejuvenated the CDKs research field. This review provides an overview of relevant advances on CDK inhibitor research since 2015 to 2019, with special emphasis on transcriptional CDK inhibitors, new emerging strategies such as target protein degradation and compounds under clinical evaluation.

EZH2 inhibitor DZNep modulates microglial activation and protects against ischaemic brain injury after experimental stroke

Enhancer of zeste homolog-2 (EZH2), a histone methyltransferase, has been recognized to play a pivotal role in regulating the immune response in various diseases. However, its role in the inflammatory response induced by ischaemic stroke remains to be further investigated. The aim of this study was to determine the role of EZH2 in microglia-associated inflammation in ischaemic stroke and to further detect the effects of the EZH2 inhibitor, 3-deazaadenosine A (DZNep), in ischaemic brain injury. Here, we found that both in vivo ischemic/reperfusion (I/R) injury and in vitro oxygen-glucose deprivation (OGD) treatment induced a marked upregulation of EZH2 in microglia. The administration of the EZH2 inhibitor DZNep improved behavioural performance and reduced the infarct volume in mice after experimental stroke. Furthermore, we showed that DZNep blocked pro-inflammatory (CD86⁺) microglial activation and triggered anti-inflammatory (CD206⁺) microglial polarization in experimental stroke. Pro-inflammatory cytokines such as IL-1β, IL-6, TNF-α and CXCL10 were also significantly downregulated by DZNep. In addition, it was found that DZNep blocked the phosphorylation of signal transducer and activator of transcription 3 (STAT3) in microglia, which was increased by I/R injury and OGD. Collectively, we demonstrated that EZH2 is implicated in regulating microglial activation and exacerbates neurological deficits after ischaemic stroke, probably via activating STAT3, and that the EZH2 inhibitor DZNep can exert neuroprotective effects after ischaemic stroke.

Differential gene expression induced by Verteporfin in endometrial cancer cells

Endometrial cancer (EMCA) is a clinically heterogeneous disease. Previously, we tested the efficacy of Verteporfin (VP) in EMCA cells and observed cytotoxic and anti-proliferative effects. In this study, we analyzed RNA sequencing data to investigate the comprehensive transcriptomic landscape of VP treated Type 1 EMCA cell lines, including HEC-1-A and HEC-1-B. There were 549 genes with differential expression of two-fold or greater and P < 0.05 after false discovery rate correction for the HEC-1-B cell line. Positive regulation of TGFβ1 production, regulation of lipoprotein metabolic process, cell adhesion, endodermal cell differentiation, formation and development, and integrin mediated signaling pathway were among the significantly associated terms. A functional enrichment analysis of differentially expressed genes after VP treatment revealed extracellular matrix organization Gene Ontology as the most significant. CDC23 and BUB1B, two genes crucially involved in mitotic checkpoint progression, were found to be the pair with the best association from STRING among differentially expressed genes in VP treated HEC-1-B cells. Our in vivo results indicate that subcutaneous tumors in mice were regressed after VP treatment by inhibiting cell cycle pathway proteins. The present study revealed multiple key genes of pathological significance in EMCA, thereby improving our understanding of molecular profiles of EMCA cells.

An inflammatory-CCRK circuitry drives mTORC1-dependent metabolic and immunosuppressive reprogramming in obesity-associated hepatocellular carcinoma

Obesity increases the risk of hepatocellular carcinoma (HCC) especially in men, but the molecular mechanism remains obscure. Here, we show that an androgen receptor (AR)-driven oncogene, cell cycle-related kinase (CCRK), collaborates with obesity-induced pro-inflammatory signaling to promote non-alcoholic steatohepatitis (NASH)-related hepatocarcinogenesis. Lentivirus-mediated Ccrk ablation in liver of male mice fed with high-fat high-carbohydrate diet abrogates not only obesity-associated lipid accumulation, glucose intolerance and insulin resistance, but also HCC development. Mechanistically, CCRK fuels a feedforward loop by inducing STAT3-AR promoter co-occupancy and transcriptional up-regulation, which in turn activates mTORC1/4E-BP1/S6K/SREBP1 cascades via GSK3β phosphorylation. Moreover, hepatic CCRK induction in transgenic mice stimulates mTORC1-dependent G-csf expression to enhance polymorphonuclear myeloid-derived suppressor cell recruitment and tumorigenicity. Finally, the STAT3-AR-CCRK-mTORC1 pathway components are concordantly over-expressed in human NASH-associated HCCs. These findings unveil the dual roles of an inflammatory-CCRK circuitry in driving metabolic and immunosuppressive reprogramming through mTORC1 activation, thereby establishing a pro-tumorigenic microenvironment for HCC development.

Androgen receptor drives hepatocellular carcinogenesis by activating enhancer of zeste homolog 2-mediated Wnt/β-catenin signaling

Background

Androgen receptor (AR) plays a crucial role as a transcription factor in promoting the development of hepatocellular carcinoma (HCC) which is prone to aberrant chromatin modifications. However, the regulatory effects of AR on epigenetic mediators in HCC remain ill-defined. Enhancer of zeste homolog 2 (EZH2), an oncogene responsible for the tri-methylation of histone H3 at lysine 27 (H3K27me3), was identified to be overexpressed in approximate 70–90% of HCC cases, which prompted us to investigate whether or how AR regulates EZH2 expression.

Methods

Colony formation, soft agar assay, xenograft and orthotopic mouse models were used to determine cell proliferation and tumorigenicity of gene-manipulated HCC cells. Gene regulation was assessed by chromatin immunoprecipitation, luciferase reporter assay, quantitative RT-PCR and immunoblotting. Clinical relevance of candidate proteins in patient specimens was examined in terms of pathological parameters and postsurgical survival rates.

Findings

In this study, we found that AR upregulated EZH2 expression by binding to EZH2 promoter and stimulating its transcriptional activity. EZH2 overexpression increased H3K27me3 levels and thereby silenced the expression of Wnt signal inhibitors, resulting in activation of Wnt/β-catenin signaling and subsequently induction of cell proliferation and tumorigenesis. In a cohort of human HCC patients, concordant overexpression of AR, EZH2, H3K27me3 and active β-catenin was observed in tumor tissues compared with paired non-tumor tissues, which correlated with tumor progression and poor prognosis. These findings demonstrate a novel working model in which EZH2 mediates AR-induced Wnt/β-catenin signaling activation through epigenetic modification, and support the application of EZH2-targeted reagents for treating HCC patients.