Targeting the NCOA3-SP1-TERT axis for tumor growth in hepatocellular carcinoma

LKB1 inhibits telomerase activity resulting in cellular senescence through histone lactylation in lung adenocarcinoma

Despite the confirmed role of LKB1 in suppressing lung cancer progression, its precise effect on cellular senescence is unknown. The aim of this research was to clarify the role and mechanism of LKB1 in restraining telomerase activity in lung adenocarcinoma. The results showed that LKB1 induced cellular senescence and apoptosis either in vitro or in vivo. Overexpression of LKB1 in LKB1-deficient A549 cells led to the inhibition of telomerase activity and the induction of telomere dysfunction by regulating telomerase reverse transcriptase (TERT) expression in terms of transcription. As a transcription factor, Sp1 mediated TERT inhibition after LKB1 overexpression. LKB1 induced lactate production and inhibited histone H4 (Lys8) and H4 (Lys16) lactylation, which further altered Sp1-related transcriptional activity. The telomerase inhibitor BIBR1532 was beneficial for achieving the optimum curative effect of traditional chemotherapeutic drugs accompanied by the glycolysis inhibitor 2DG. These data reveal a new mechanism by which LKB1 regulates telomerase activity through lactylation-dependent transcriptional inhibition, and therefore, provide new insights into the effects of LKB1-mediated senescence in lung adenocarcinoma. Our research has opened up new possibilities for the creation of new cancer treatments.

Pathological discrimination between luteinized thecoma associated with sclerosing peritonitis and thecoma

BACKGROUND

Similarities between luteinized thecoma associated with sclerosing peritonitis (LTSP) and thecoma, cause difficulty in clinical differential diagnoses. To improve the situation, we selected 10 specified molecular pathological markers that are frequently used in clinical pathology of ovarian sex cord-stromal tumors to determine whether they exert a discriminatory effect.

METHODS

Applying immunohistochemistry, we analyzed the expression of alpha-1,6-mannosylglycoprotein 6-beta-n-acetylglucosaminyltransferase B (MGAT5B), nuclear receptor coactivator 3 (NCOA3), proliferation marker protein Ki-67 (MKI67), estrogen receptor, progesterone receptor, Vimentin, receptor tyrosine-protein kinase erbB-2, Catenin beta-1 (β-Catenin), CD99 antigen (CD99) and Wilms tumor protein (WT1) in 102 cases of diseases containing 11 LTSP and 91 thecoma. Whole-exome sequencing and fluorescence in situ hybridization were used to examine the MGAT5B-NCOA3 fusion gene in LTSP. Statistical analysis was performed using t test, one-way analysis of variance test, and post hoc test.

RESULTS

Six significant markers were verified for the discrimination between LTSP and thecoma, containing 4 upregulating indicators MGAT5B, NCOA3, MKI67, β-Catenin, and 2 downregulating markers CD99 and WT1 in luteinized cells. In addition, the MGAT5B-NCOA3 fusion gene was identified in LTSP for the first time with significantly rich expression compared to thecoma.

CONCLUSIONS

We verified 6 significant molecular pathological markers containing MGAT5B, NCOA3, MKI67, β-Catenin, CD99, and WT1 and identified MGAT5B-NCOA3 fusion gene in LTSP; this work will help clinicians to discriminate between medical conditions and treat patients accurately.

Mapping Multi-factor-mediated Chromatin Interactions to Assess Dysregulation of Lung Cancer-related Genes

Studies on the lung cancer genome are indispensable for developing a cure for lung cancer. Whole-genome resequencing, genome-wide association studies, and transcriptome sequencing have greatly improved our understanding of the cancer genome. However, dysregulation of long-range chromatin interactions in lung cancer remains poorly described. To better understand the three-dimensional (3D) genomic interaction features of the lung cancer genome, we used the A549 cell line as a model system and generated high-resolution chromatin interactions associated with RNA polymerase II (RNAPII), CCCTC-binding factor (CTCF), enhancer of zeste homolog 2 (EZH2), and histone 3 lysine 27 trimethylation (H3K27me3) using long-read chromatin interaction analysis by paired-end tag sequencing (ChIA-PET). Analysis showed that EZH2/H3K27me3-mediated interactions further repressed target genes, either through loops or domains, and their distributions along the genome were distinct from and complementary to those associated with RNAPII. Cancer-related genes were highly enriched with chromatin interactions, and chromatin interactions specific to the A549 cell line were associated with oncogenes and tumor suppressor genes, such as additional repressive interactions on FOXO4 and promoter-promoter interactions between NF1 and RNF135. Knockout of an anchor associated with chromatin interactions reversed the dysregulation of cancer-related genes, suggesting that chromatin interactions are essential for proper expression of lung cancer-related genes. These findings demonstrate the 3D landscape and gene regulatory relationships of the lung cancer genome.

Specificity Proteins (SP) and Krüppel-like Factors (KLF) in Liver Physiology and Pathology

The liver acts as a central hub that controls several essential physiological processes ranging from metabolism to detoxification of xenobiotics. At the cellular level, these pleiotropic functions are facilitated through transcriptional regulation in hepatocytes. Defects in hepatocyte function and its transcriptional regulatory mechanisms have a detrimental influence on liver function leading to the development of hepatic diseases. In recent years, increased intake of alcohol and western diet also resulted in a significantly increasing number of people predisposed to the incidence of hepatic diseases. Liver diseases constitute one of the serious contributors to global deaths, constituting the cause of approximately two million deaths worldwide. Understanding hepatocyte transcriptional mechanisms and gene regulation is essential to delineate pathophysiology during disease progression. The current review summarizes the contribution of a family of zinc finger family transcription factors, named specificity protein (SP) and Krüppel-like factors (KLF), in physiological hepatocyte functions, as well as how they are involved in the onset and development of hepatic diseases.

Protective role of circRNA CCND1 in ulcerative colitis via miR-142-5p/NCOA3 axis

BACKGROUND

Increasing research indicates that circular RNAs (circRNAs) play critical roles in the development of ulcerative colitis (UC). This study aimed to determine the role of circRNA CCND1 in UC bio-progression, which has been shown to be downregulated in UC tissues.

METHODS

Reverse transcription quantitative polymerase chain reaction was used to determine the levels of circRNA CCND1, miR-142-5p, and nuclear receptor coactivator-3 (NCOA3) in UC tissues and in lipopolysaccharide (LPS)-induced Caco-2 cells. Target sites of circRNA CCND1 and miR-142-5p were predicted using StarBase, and TargetScan to forecast potential linkage points of NCOA3 and miR-142-5p, which were confirmed by a double luciferase reporter-gene assay. Cell Counting Kit 8 and flow cytometry assays were performed to assess Caco-2 cell viability and apoptosis. TNF-α, IL-1β, IL-6, and IL-8 were detected using Enzyme-Linked Immunosorbent Assay kits.

RESULTS

CircRNA CCND1 was downregulated in UC clinical samples and LPS-induced Caco-2 cells. In addition, circRNA CCND1 overexpression suppressed LPS-induced apoptosis and inflammatory responses in Caco-2 cells. Dual-luciferase reporter-gene assays showed that miR-142-5p could be linked to circRNA CCND1. Moreover, miR-142-5p was found to be highly expressed in UC, and its silencing inhibited LPS-stimulated Caco-2 cell apoptosis and inflammatory responses. Importantly, NCOA3 was found downstream of miR-142-5p. Overexpression of miR-142-5p reversed the inhibitory effect of circRNA CCND1-plasmid on LPS-stimulated Caco-2 cells, and the effects of miR-142-5p inhibitor were reversed by si-NCOA3.

CONCLUSION

CircRNA CCND1 is involved in UC development by dampening miR-142-5p function, and may represent a novel approach for treating UC patients.

Pathogenesis and Current Treatment Strategies of Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the most frequent liver cancer with high lethality and low five-year survival rates leading to a substantial worldwide burden for healthcare systems. HCC initiation and progression are favored by different etiological risk factors including hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, non-/and alcoholic fatty liver disease (N/AFLD), and tobacco smoking. In molecular pathogenesis, endogenous alteration in genetics (TP53, TERT, CTNNB1, etc.), epigenetics (DNA-methylation, miRNA, lncRNA, etc.), and dysregulation of key signaling pathways (Wnt/β-catenin, JAK/STAT, etc.) strongly contribute to the development of HCC. The multitude and complexity of different pathomechanisms also reflect the difficulties in tailored medical therapy of HCC. Treatment options for HCC are strictly dependent on tumor staging and liver function, which are structured by the updated Barcelona Clinic Liver Cancer classification system. Surgical resection, local ablative techniques, and liver transplantation are valid and curative therapeutic options for early tumor stages. For multifocal and metastatic diseases, systemic therapy is recommended. While Sorafenib had been the standalone HCC first-line therapy for decades, recent developments had led to the approval of new treatment options as first-line as well as second-line treatment. Anti-PD-L1 directed combination therapies either with anti-VEGF directed agents or with anti-CTLA-4 active substances have been implemented as the new treatment standard in the first-line setting. However, data from clinical trials indicate different responses on specific therapeutic regimens depending on the underlying pathogenesis of hepatocellular cancer. Therefore, histopathological examinations have been re-emphasized by current international clinical guidelines in addition to the standardized radiological diagnosis using contrast-enhanced cross-sectional imaging. In this review, we emphasize the current knowledge on molecular pathogenesis of hepatocellular carcinoma. On this occasion, the treatment sequences for early and advanced tumor stages according to the recently updated Barcelona Clinic Liver Cancer classification system and the current algorithm of systemic therapy (first-, second-, and third-line treatment) are summarized. Furthermore, we discuss novel precautional and pre-therapeutic approaches including therapeutic vaccination, adoptive cell transfer, locoregional therapy enhancement, and non-coding RNA-based therapy as promising treatment options. These novel treatments may prolong overall survival rates in regard with quality of life and liver function as mainstay of HCC therapy.

Inducing Synergistic DNA Damage by TRIP13 and PARP1 Inhibitors Provides a Potential Treatment for Hepatocellular Carcinoma

Thyroid hormone receptor interactor 13 (TRIP13), an AAA-ATPase, participates in the development of many cancers. This study explores the function of TRIP13 and synergistic effects of TRIP13 and PARP1 inhibitors in hepatocellular carcinoma (HCC). The dose-dependent effects of TRIP13 and PARP1 inhibitors on HCC cells proliferation or migration were investigated by the CCK-8 and Transwell assays. Using siRNA or lentivirus to knock down TRIP13, we tested HCC cell and tumor growth in vitro and in vivo. The DNA damage caused by TRIP13 and PARP1 inhibitors was measured by the phosphorylation of H2AX, one of the DNA damage biomarkers. The phosphorylation of H2AX was increased after treatment with DCZ0415 or TRIP13 knockdown. Combining DCZ0415 with PARP1 inhibitor, Olaparib induced synergistic anti-HCC activity. We also found that the overexpression of TRIP13 is significantly associated with early recurrent HCC and poor survival. Up-regulation of TRIP13 in HCC was regulated by transcription factor SP1. In conclusion, our study demonstrated that DCZ0415 targeting TRIP13 impaired non-homologous end-joining repair to inhibit HCC progression and had a synergistic effect with PARP1 inhibitor Olaparib in HCC, suggesting a potential treatment of HCC.

Multidimensional Analysis of CHMP Family Members in Hepatocellular Carcinoma

Background

EGFR frequently accumulates and mutates simultaneously in various cancers. Ubiquitinated EGFR proteins can be degraded by the endosomal sorting complex required for transport. Among them, ESCRTIII is mainly composed of CHMP family members.

Methods

A total of 424 samples from the TCGA-LIHC data set were used to explore the relationship between CHMPs and liver hepatocellular carcinoma (LIHC). Oncomine, the Human Protein Altas, cBioPortal, TISIDB, TIMER, Metascape, and R software were used to facilitate analysis of the role played by CHMPs in the pathogenesis of LIHC. The role of CHMPs in the development of LIHC was analyzed in terms of differential expression, survival, mutation, immunoinfiltration, functional enrichment, and drug sensitivity.

Results

Differential expression analysis showed that CHMPs were significantly more expressed in LIHC tumor tissue, and the high expression of some CHMPs was closely correlated with clinicopathological stage. The prognosis was worse in the group with high expression of CHMPs. Among them, CHMP4C was considered to play a major role. Gene-mutation analysis and DNA promoter–methylation analysis further revealed possible mechanisms for the aberrant amplification of CHMPs. Immunoinfiltration analysis indicated that CHMPs were closely associated with multiple immune cells and exhibited resistance to various drugs when highly expressed.

Conclusion

CHMPs were found to be significantly elevated in LIHC and strongly associated with immune-cell infiltration, poor prognosis, multiple star pathways, and drug resistance.

Conditional ERK3 overexpression cooperates with PTEN deletion to promote lung adenocarcinoma formation in mice

ERK3, officially known as mitogen‐activated protein kinase 6 (MAPK6), is a poorly studied mitogen‐activated protein kinase (MAPK). Recent studies have revealed the upregulation of ERK3 expression in cancer and suggest an important role for ERK3 in promoting cancer cell growth and invasion in some cancers, in particular lung cancer. However, it is unknown whether ERK3 plays a role in spontaneous tumorigenesis in vivo. To determine the role of ERK3 in lung tumorigenesis, we created a conditional ERK3 transgenic mouse line in which ERK3 transgene expression is controlled by Cre recombinase. By crossing these transgenic mice with a mouse line harboring a lung tissue–specific Cre recombinase transgene driven by a club cell secretory protein gene promoter (CCSP‐iCre), we have found that conditional ERK3 overexpression cooperates with phosphatase and tensin homolog (PTEN) deletion to induce the formation of lung adenocarcinomas (LUADs). Mechanistically, ERK3 overexpression stimulates activating phosphorylations of erb‐b2 receptor tyrosine kinases 2 and 3 (ERBB2 and ERBB3) by upregulating Sp1 transcription factor (SP1)–mediated gene transcription of neuregulin 1 (NRG1), a potent ligand for ERBB2/ERBB3. Our study has revealed a bona fide tumor‐promoting role for ERK3 using genetically engineered mouse models. Together with previous findings showing the roles of ERK3 in cultured cells and in a xenograft lung tumor model, our findings corroborate that ERK3 acts as an oncoprotein in promoting LUAD development and progression.

PFKFB4 is overexpressed in clear-cell renal cell carcinoma promoting pentose phosphate pathway that mediates Sunitinib resistance

Background

Kinases play critical role in clear-cell renal cell carcinoma (ccRCC). We aim to exploit novel kinase that is both protumorigenic and drugable in ccRCC.

Methods

Reproduction of public datasets with validation using microarray was performed to identify candidate gene. Functionality was studied using multi-omics with validation in vitro and in vivo.

Results

6-Phosphofructo-2-Kinase/Fructose-2,6-Biphosphatase 4 (PFKFB4) was differentially expressed showing significantly higher expression in tumor than in normal kidney. PFKFB4 overexpression was associated with advanced tumor grade, stage and worsened prognosis. PFKFB4-knockdown significantly impaired fitness in cell proliferation, migration and wound healing. Despite being recurrently deleted on 3p, PFKFN4 mRNA remained actively transcribed by HIF1α. Metabolomics showed overexpressed PFKFB4 showed enriched metabolites in pentose phosphate pathway (PPP). Phosphoproteomics and immunoprecipitation showed PFKFB4 also phosphorylated NCOA3 which interacted with FBP1 to counteract overactive PPP flux, forming a regulatory loop. PFKFB4-knockdown overcame resistance to Sunitinib in vitro and in vivo both in xenograft and tail-vein injection murine models.

Conclusion

We concluded PFKFB4 was associated with PPP activity and the fine-tuning of which was mediated by its phosphorylation of NCOA3. Targeting PFKFB4 held promise to combat resistance to Sunitinib.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-02103-5.

Metformin inhibits MAPK signaling and rescues pancreatic aquaporin 7 expression to induce insulin secretion in type 2 diabetes mellitus

Metformin is the first-line antidiabetic agent for type 2 diabetes mellitus (T2DM) treatment. Although accumulated evidence has shed light on the consequences of metformin action, the precise mechanisms of its action, especially in the pancreas, are not fully understood. Aquaporin 7 (AQP7) acts as a critical regulator of intraislet glycerol content, which is necessary for insulin production and secretion. The aim of this study was to investigate the effects of different doses of metformin on AQP7 expression and explore the possible mechanism of its protective effects in the pancreatic islets. We used an in vivo model of high-fat diet in streptozocin-induced diabetic rats and an in vitro model of rat pancreatic β-cells (INS-1 cells) damaged by hyperglycemia and hyperlipidemia. Our data showed that AQP7 expression levels were decreased, whereas p38 and JNK mitogen-activated protein kinases (MAPKs) were activated in vivo and in vitro in response to hyperglycemia and hyperlipidemia. T2DM rats treated with metformin demonstrated a reduction in blood glucose levels and increased regeneration of pancreatic β-cells. In addition, metformin upregulated AQP7 expression as well as inhibited activation of p38 and JNK MAPKs both in vivo and in vitro. Overexpression of AQP7 increased glycerol influx into INS-1 cells, whereas inhibition of AQP7 reduced glycerol influx, thereby decreasing subsequent insulin secretion. Our findings demonstrate a new mechanism by which metformin suppresses the p38 and JNK pathways, thereby upregulating pancreatic AQP7 expression and promoting glycerol influx into pancreatic β-cells and subsequent insulin secretion in T2DM.