Overexpression of TONSL might be an independent unfavorable prognostic indicator in hepatocellular carcinoma

TONSL promotes lung adenocarcinoma progression, immune escape and drug sensitivity

PURPOSE

The tonsoku-like DNA repair protein (TONSL) encoded by the TONSL gene, located on chromosome 8q24.3, is crucial for repairing DNA double-strand breaks through homologous recombination. However, TONSL overexpression in lung adenocarcinoma (LUAD) promotes tumor development, leading to a poor prognosis.

METHODS

TONSL was verified as a reliable prognostic marker for LUAD using bioinformatics, and clinical features related to LUAD prognosis were screened from the TCGA database to establish the relationship between risk factors and TONSL expression. In addition, TONSL expression in normal and LUAD tissues was verified using real-time quantitative polymerase chain reaction and immunohistochemistry. To elucidate the possible functions of TONSL, TONSL-related differentially expressed genes were screened, and functional enrichment analysis was performed. Subsequently, siRNA was used to knock down TONSL expression in lung cancer cells for cytobehavioral experiments. The effects of TONSL expression on tumor immune escape were analyzed using the ESTIMATE algorithm and tumor immune-infiltration analysis. In addition, the half-maximal inhibitory concentration of LUAD with varying TONSL expression levels in response to first-line chemotherapeutic drugs and epidermal growth factor receptor-tyrosine kinase inhibitors was analyzed for drug sensitivity.

RESULTS

Up-regulation of TONSL in LUAD promotes the proliferation, migration, and invasion of lung cancer cells, thereby contributing to a poor prognosis. Furthermore, TONSL overexpression promotes immune escape and drug sensitivity in LUAD.

CONCLUSION

TONSL serves as a reliable prognostic marker for LUAD, and its up-regulation is associated with increased immune escape and drug sensitivity. These findings suggest that TONSL holds potential as a novel therapeutic target for LUAD.

Application of Protein-Protein Interaction Network Analysis in Order to Identify Cervical Cancer miRNA and mRNA Biomarkers

Cervical cancer (CC) is one of the world's most common and severe cancers. This cancer includes two histological types: squamous cell carcinoma (SCC) and adenocarcinoma (ADC). The current study aims at identifying novel potential candidate mRNA and miRNA biomarkers for SCC based on a protein-protein interaction (PPI) and miRNA-mRNA network analysis. The current project utilized a transcriptome profile for normal and SCC samples. First, the PPI network was constructed for the 1335 DEGs, and then, a significant gene module was extracted from the PPI network. Next, a list of miRNAs targeting module's genes was collected from the experimentally validated databases, and a miRNA-mRNA regulatory network was formed. After network analysis, four driver genes were selected from the module's genes including MCM2, MCM10, POLA1, and TONSL and introduced as potential candidate biomarkers for SCC. In addition, two hub miRNAs, including miR-193b-3p and miR-615-3p, were selected from the miRNA-mRNA regulatory network and reported as possible candidate biomarkers. In summary, six potential candidate RNA-based biomarkers consist of four genes containing MCM2, MCM10, POLA1, and TONSL, and two miRNAs containing miR-193b-3p and miR-615-3p are opposed as potential candidate biomarkers for CC.

Absence of Either Ripk3 or Mlkl Reduces Incidence of Hepatocellular Carcinoma Independent of Liver Fibrosis

Nonalcoholic fatty liver disease (NAFLD) is one of the etiologies that contribute to hepatocellular carcinoma (HCC), and chronic inflammation is one of the proposed mediators of HCC. Because necroptosis is a cell death pathway that induces inflammation, we tested whether necroptosis-induced inflammation contributes to the progression of NAFLD to HCC in a mouse model of diet-induced HCC. Male and female wild-type (WT) mice and mouse models where necroptosis is blocked (Ripk3-/- or Mlkl-/- mice) were fed either a control diet, choline-deficient low-fat diet or choline-deficient high-fat diet. Blocking necroptosis reduced markers of inflammation [proinflammatory cytokines (TNFα, IL6, and IL1β), F4/80+ve macrophages, CCR2+ve infiltrating monocytes], inflammation-associated oncogenic pathways (JNK, PD-L1/PD-1, β-catenin), and HCC in male mice. We demonstrate that hepatic necroptosis promotes recruitment and activation of liver macrophages leading to chronic inflammation, which in turn trigger oncogenic pathways leading to the progression of NAFLD to HCC in male mice. Whereas in female mice, blocking necroptosis reduced HCC independent of inflammation. Our data show a sex-specific difference in the development of inflammation, fibrosis, and HCC in WT mice. However, blocking necroptosis reduced HCC in both males and females without altering liver fibrosis. Thus, our study suggests that necroptosis is a valid therapeutic target for NAFLD-mediated HCC.

IMPLICATIONS

Necroptosis is a major contributor to hepatic inflammation that drives the progression of NAFLD to HCC and therefore represents a valid target for NAFLD-mediated HCC.

High PPT1 expression predicts poor clinical outcome and PPT1 inhibitor DC661 enhances sorafenib sensitivity in hepatocellular carcinoma

Background

Adaptive resistance and side effects of sorafenib treatment result in unsatisfied survival of patients with hepatocellular carcinoma (HCC). Palmitoyl-protein thioesterase 1 (PPT1) plays a critical role in progression of various cancers. However, its role on prognosis and immune infiltrates in HCC remains unclarified.

Methods

By data mining in the Cancer Genome Atlas databases, the role of PPT1 in HCC were initially investigated. Furthermore, HCC cell lines Hep 3B and Hep 1-6 were treated with DC661 or siRNA against PPT1. The biological function of PPT1 was determined by CCK-8 test, colony formation assay, TUNEL staining, immunofluorescence staining, Western blot test, and PI-Annexin V apoptosis assays in vitro. Animal models of subcutaneous injection were applied to investigate the therapeutic role of targeting PPT1.

Results

We found that PPT1 levels were significantly upregulated in HCC tissues compared with normal tissues and were significantly associated with a poor prognosis. Multivariate analysis further confirmed that high expression of PPT1 was an independent risk factor for poor overall survival of HCC patients. We initially found that PPT1 was significantly upregulated in sorafenib-resistant cell lines established in this study. Upon sorafenib treatment, HCC cells acquired adaptive resistance by inducing autophagy. We found that DC661, a selective and potent small-molecule PPT1-inhibitor, induced lysosomal membrane permeability, caused lysosomal deacidification, inhibited autophagy and enhanced sorafenib sensitivity in HCC cells. Interestingly, this sensitization effect was also mediated by the induction mitochondrial pathway apoptosis. In addition, the expression level of PPT1 was associated with the immune infiltration in the HCC tumor microenvironment, and PPT1 inhibitor DC661 significantly enhanced the anti-tumor immune response by promoting dendritic cell maturation and further promoting CD8+ T cell activation. Moreover, DC661 combined with sorafenib was also very effective at treating tumor models in immunized mice.

Conclusions

Our findings suggest that targeting PPT1 with DC661 in combination with sorafenib might be a novel and effective alternative therapeutic strategy for HCC.

MicroRNA signature in liver cancer

Liver cancer is the 7^th utmost frequent neoplasm and the 4^th principal source of cancer deaths. This malignancy is linked with several environmental and lifestyle-related factors emphasizing the role of epigenetics in its pathogenesis. MicroRNAs (miRNAs) have been regarded as potent epigenetic mechanisms partaking in the pathogenesis of liver cancer. Dysregulation of miRNAs has been related with poor outcome of patients with liver cancer. In the current manuscript, we provide a concise review of the results of recent studies about the role of miRNAs in the progression of liver cancer and their diagnostic and prognostic utility.

Targeting Non-Oncogene Addiction for Cancer Therapy

While Next-Generation Sequencing (NGS) and technological advances have been useful in identifying genetic profiles of tumorigenesis, novel target proteins and various clinical biomarkers, cancer continues to be a major global health threat. DNA replication, DNA damage response (DDR) and repair, and cell cycle regulation continue to be essential systems in targeted cancer therapies. Although many genes involved in DDR are known to be tumor suppressor genes, cancer cells are often dependent and addicted to these genes, making them excellent therapeutic targets. In this review, genes implicated in DNA replication, DDR, DNA repair, cell cycle regulation are discussed with reference to peptide or small molecule inhibitors which may prove therapeutic in cancer patients. Additionally, the potential of utilizing novel synthetic lethal genes in these pathways is examined, providing possible new targets for future therapeutics. Specifically, we evaluate the potential of TONSL as a novel gene for targeted therapy. Although it is a scaffold protein with no known enzymatic activity, the strategy used for developing PCNA inhibitors can also be utilized to target TONSL. This review summarizes current knowledge on non-oncogene addiction, and the utilization of synthetic lethality for developing novel inhibitors targeting non-oncogenic addiction for cancer therapy.

Downregulation of LUZP2 Is Correlated with Poor Prognosis of Low-Grade Glioma

Background

LUZP2 is a protein limitedly expressed in the brain and spinal cord, while there are few studies on it in brain tumors. Low-grade glioma (LGG) is one of the most common brain tumors. However, the biological behavior of LGG is not very clear at present. This study was aimed at exploring the role of LUZP2 in LGG.

Methods

By data mining in The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA), the expression, clinical characteristics, and potential regulatory mechanism of LUZP2 in LGG were assessed. The regulatory miRNAs of LUZP2 were predicted using miRDB, TargetScan, and miRTarBase. Meanwhile, the potential biological function of coexpressed genes was investigated by GO and KEGG analyses.

Results

LUZP2 expression was downregulated with the increase of tumor grade (p < 0.05). Low LUZP2 expression independently predicted poor OS in LGG in TCGA cohort and the CGGA part B and part C cohorts (all p < 0.001). Additionally, LUZP2 was targeted by miR-142-5p according to 2 prediction databases and 1 validated database, which was negatively related to LUZP2 mRNA expression (p < 0.001). Kaplan-Meier analyses demonstrated that low miR-142-5p expression was significantly associated with poor OS (p < 0.001). Furthermore, coexpression genes of LUZP2 were significantly involved in nervous system development and metabolic pathways.

Conclusions

LUZP2 may be crucial for nervous system extracellular matrix development and serve as an important clinical biomarker for LGG patients. miR-142-5p upregulation could be the upstream regulator that contributed to LUZP2 downregulation.

A novel strategy for the diagnosis, prognosis, treatment, and chemoresistance of hepatocellular carcinoma: DNA methylation

The cancer mortality rate of hepatocellular carcinoma (HCC) is the second highest in the world and the therapeutic options are limited. The incidence of this deadly cancer is rising at an alarming rate because of the high degree of resistance to chemo- and radiotherapy, lack of proper, and adequate vaccination to hepatitis B, and lack of consciousness and knowledge about the disease itself and the lifestyle of the people. DNA methylation and DNA methylation-induced epigenetic alterations, due to their potential reversibility, open the access to develop novel biomarkers and therapeutics for HCC. The contribution to these epigenetic changes in HCC development still has not been thoroughly summarized. Thus, it is necessary to better understand the new molecular targets of HCC epigenetics in HCC diagnosis, prevention, and treatment. This review elaborates on recent key findings regarding molecular biomarkers for HCC early diagnosis, prognosis, and treatment. Currently emerging epigenetic drugs for the treatment of HCC are summarized. In addition, combining epigenetic drugs with nonepigenetic drugs for HCC treatment is also mentioned. The molecular mechanisms of DNA methylation-mediated HCC resistance are reviewed, providing some insights into the difficulty of treating liver cancer and anticancer drug development.

Heterozygous loss of Srp72 in mice is not associated with major hematological phenotypes

OBJECTIVES

Familial cases of hematological malignancies are associated with germline mutations. In particular, heterozygous mutations of SRP72 correlate with the development of myelodysplasia and bone marrow aplasia in two families. The signal recognition particle 72 kDa protein (SRP72) is part of the SRP complex, responsible for targeting of proteins to the endoplasmic reticulum. The main objective of this study is to investigate the role of SRP72 in the hematopoietic system, thus explaining why a reduced dose could increase susceptibility to hematological malignancies.

METHODS

We developed an Srp72 null mouse model and characterized its hematopoietic system using flow cytometry, bone marrow transplantations, and gene expression analysis.

RESULTS

Heterozygous loss of Srp72 in mice is not associated with major changes in hematopoiesis, although causes mild reductions in blood and BM cellularity and minor changes within the stem/progenitor compartment. We did not observe any hematological disorder. Interestingly, gene expression analysis demonstrated that genes encoding secreted factors, including cytokines and receptors, were transcriptionally down-regulated in Srp72^+/- animals.

CONCLUSIONS

The Srp72^+/- mouse model only partially recapitulates the phenotype observed in families with inherited SRP72 lesions. Nonetheless, these results can provide mechanistic insights into why SRP72 mutations are associated with aplasia and myelodysplasia in humans.