Galectin-14 promotes hepatocellular carcinoma tumor growth via enhancing heparan sulfate proteoglycan modification

Hepatocellular carcinoma(HCC)is a highly heterogeneous malignancy and lacks effective treatment.Bulk-sequencing of different gene transcripts by comparing HCC tissues and adjacent normal tissues provides some clues for investigating the mechanisms or identifying potential targets for tumor progression.However,genes that are exclusively expressed in a subpopulation of HCC may not be enriched or detected through such a screening.In the current study,we performed a single cell-clone-based screening and identified galectin-14 as an essential molecule in the regulation of tumor growth.The aberrant expression of galectin-14 was significantly associated with a poor overall survival of liver cancer patients with database analysis.Knocking down galectin-14 inhibited the proliferation of tumor growth,whereas overexpressing galectin-14 promoted tumor growth in vivo.Non-targeted metabolomics analysis indicated that knocking down galectin-14 decreased glycometabolism;specifically that glycoside synthesis was significantly changed.Further study found that galectin-14 promoted the expression of cell surface heparan sulfate proteoglycans(HSPGs)that functioned as co-receptors,thereby increasing the responsiveness of HCC cells to growth factors,such as epidermal growth factor and transforming growth factor-alpha.In conclusion,the current study identifies a novel HCC-specific molecule galectin-14,which increases the expression of cell surface HSPGs and the uptake of growth factors to promote HCC cell proliferation.

A Novel ATM Antisense Transcript ATM-AS Positively Regulates ATM Expression in Normal and Breast Cancer Cells

Objective:The ataxia telangiectasia mutated(ATM)gene is a master regulator in cellular DNA damage response.The dysregulation of ATM expression is frequent in breast cancer,and is known to be involved in the carcinogenesis and prognosis of cancer.However,the underlying mechanism remains unclear.The bioinformatic analysis predicted a potential antisense transcript ATM-antisense(AS)from the opposite strand of the ATM gene.The purpose of this study was to identify ATM-AS and investigate the possible effect of ATM-AS on the ATM gene regulation.Methods:Single strand-specific RT-PCR was performed to verify the predicted antisense transcript ATM-AS within the ATM gene locus.qRT-PCR and Western blotting were used to detect the expression levels of ATM-AS and ATM in normal and breast cancer cell lines as well as in tissue samples.Luciferase reporter gene assays,biological mass spectrometry,ChIP-qPCR and RIP were used to explore the function of ATM-AS in regulating the ATM expression.Immunofluorescence and host-cell reactivation(HCR)assay were performed to evaluate the biological significance of ATM-AS in ATM-mediated DNA damage repair.Breast cancer tissue samples were used for evaluating the correlation of the ATM-AS level with the ATM expression as well as prognosis of the patients.Results:The ATM-AS significantly upregulated the ATM gene activity by recruiting KAT5 histone acetyltransferase to the gene promoter.The reduced ATM-AS level led to the abnormal downregulation of ATM expression,and impaired the ATM-mediated DNA damage repair in normal breast cells in vitro.The ATM-AS level was positively correlated with the ATM expression in the examined breast cancer tissue samples,and the patient prognosis.Conclusion:The present study demonstrated that ATM-AS,an antisense transcript located within the ATM gene body,is an essential positive regulator of ATM expression,and functions by mediating the binding of KAT5 to the ATM promoter.These findings uncover the novel mechanism underlying the dysregulation of the ATM gene in breast cancer,and enrich our understanding of how an antisense transcript regulates its host gene.

Immunotherapy in biliary tract cancers:Current evidence and future perspectives

Bile duct tumors are comprised of tumors that originate from both intrahepatic and extrahepatic bile ducts and gallbladder tumors.These are aggressive tumors and chemotherapy is still the main treatment for advanced-stage disease and most of these cases have a poor overall survival.Strategies are aimed at treatments with better outcomes and less toxicity which makes immunotherapy an area of significant importance.Recent Food and Drug Administration approvals of immune checkpoint inhibitors(ICI)for agnostic tumors based on biomarkers such as microsatellite instability-high and tumor mutation burden-high are important steps in the treatment of patients with advanced bile duct tumors.Despite limited responses with isolated checkpoint inhibitors in later lines of systemic treatment in advanced disease,drug combination strategies have been demonstrating encouraging results to enhance ICI efficacy.

Improving antibody affinity through in vitro mutagenesis in complementarity determining regions

High-affinity antibodies are widely used in diagnostics and for the treatment of human diseases.However,most antibodies are isolated from semi-synthetic libraries by phage display and do not possess in vivo affinity maturation,which is triggered by antigen immunization.It is therefore necessary to engineer the affinity of these antibodies by way of in vitro assaying.In this study,we optimized the affinity of two human monoclonal antibodies which were isolated by phage display in a previous related study.For the 42A1 antibody,which targets the liver cancer antigen glypican-3,the variant T57H in the second complementarity-determining region of the heavy chain(CDR-H2)exhibited a 2.6-fold improvement in affinity,as well as enhanced cell-binding activity.For the I4A3 antibody to severe acute respiratory syndrome coronavirus 2,beneficial single mutations in CDR-H2 and CDR-H3 were randomly combined to select the best synergistic mutations.Among these,the mutation S53P-S98T improved binding affinity(about 3.7 fold)and the neutralizing activity(about 12 fold)compared to the parent antibody.Taken together,single mutations of key residues in antibody CDRs were enough to increase binding affinity with improved antibody functions.The mutagenic combination of key residues in different CDRs creates additive enhancements.Therefore,this study provides a safe and effective in vitro strategy for optimizing antibody affinity.

Estrogen receptor beta suppresses the androgen receptor oncogenic effects in triple-negative breast cancer

Background:Triple-negative breast cancer(TNBC)is an aggressive type of breast cancer associated with poor prognosis and limited treatment options.The androgen receptor(AR)has emerged as a potential therapeutic target for luminal androgen receptor(LAR)TNBC.However,multiple studies have claimed that anti-androgen therapy for AR-positive TNBC only has limited clinical benefits.This study aimed to investigate the role of AR in TNBC and its detailed mechanism.Methods:Immunohistochemistry and TNBC tissue sections were applied to investigate AR and nectin cell adhesion molecule 4(NECTIN4)expression in TNBC tissues.Then,in vitro and in vivo assays were used to explore the function of AR and estrogen receptor beta(ERβ)in TNBC.Chromatin immunoprecipitation sequencing(ChIP-seq),co-immunoprecipitation(co-IP),molecular docking method,and luciferase reporter assay were performed to identify key molecules that affect the function of AR.Results:Based on the TNBC tissue array analysis,we revealed that ERβand AR were positive in 21.92%(32/146)and 24.66%(36/146)of 146 TNBC samples,respectively,and about 13.70%(20/146)of TNBC patients were ERβpositive and AR positive.We further demonstrated the pro-tumoral effects of AR on TNBC cells,however,the oncogenic biology was significantly suppressed when ERβtransfection in LAR TNBC cell lines but not in AR-negative TNBC.Mechanistically,we identified that NECTIN4 promoter–42 bp to–28 bp was an AR response element,and that ERβinteracted with AR thus impeding the AR-mediated NECTIN4 transcription which promoted epithelial–mesenchymal transition in tumor progression.Conclusions:This study suggests that ERβfunctions as a suppressor mediating the effect of AR in TNBC prognosis and cell proliferation.Therefore,our current research facilitates a better understanding of the role and mechanisms of AR in TNBC carcinogenesis.

Cytosolic TGM2 promotes malignant progression in gastric cancer by suppressing the TRIM21-mediated ubiquitination/degradation of STAT1 in a GTP binding-dependent modality

Background:Previous studies have revealed the critical role of transglutaminase 2(TGM2)as a potential therapeutic target in cancers,but the oncogenic roles and underlying mechanisms of TGM2 in gastric cancer(GC)are not fully understood.In this study,we examined the role and potential mechanism of TGM2 in GC.Methods:Western blotting,immunohistochemistry,CCK8,colony formation and transwell assays were used to measure TGM2 expression in the GC cells and tissues and to examine the in vitro role of TGM2 in GC.Xenograft and in vivo metastasis experiments were performed to examine the in vivo role of TGM2 in GC.Gene set enrichment analysis,quantitative PCR and western blotting were conducted to screen for potential TGM2 targets involved in GC.Gain/loss-offunction and rescue experiments were conducted to detect the biological roles of STAT1 in GC cells in the context of TGM2.Co-immunoprecipitation,mass spectrometry,quantitative PCR and western blotting were conducted to identify STAT1-interacting proteins and elucidate their regulatory mechanisms.Mutations in TGM2 and two molecules(ZM39923 and A23187)were used to identify the enzymatic activity of TGM2 involved in the malignant progression of GC and elucidate the underlying mechanism.Results:In this study,we demonstrated elevated TGM2 expression in the GC tissues,which closely related to pathological grade,and predicted poor survival in patients with GC.TGM2 overexpression or knockdown promoted(and inhibited)cell proliferation,migration,and invasion,which were reversed by STAT1 knockdown or overexpression.Further studies showed that TGM2 promoted GC progression by inhibiting STAT1 ubiquitination/degradation.Then,tripartite motif-containing protein 21(TRIM21)was identified as a ubiquitin E3 ligase of STAT1 in GC.TGM2 maintained STAT1 stability by facilitating the dissociation of TRIM21 and STAT1 with GTP-binding enzymatic activity.A23187 abolished the role of TGM2 in STAT1 and reversed the pro-tumor role of TGM2 in vitro and in vivo.Conclusions:This study revealed a critical role and regulatory mechanism of TGM2 on STAT1 in GC and highlighted the potential of TGM2 as a therapeutic target,which elucidates the development of medicine or strategies by regulating the GTP-binding activity of TGM2 in GC.

N6-methyladenosine modification of CENPF mRNA facilitates gastric cancer metastasis via regulating FAK nuclear export

Background:N6-methyladenosine(m^(6)A)modification is the most common modification that occurs in eukaryotes.Although substantial effort has been made in the prevention and treatment of gastric cancer(GC)in recent years,the prognosis of GC patients remains unsatisfactory.The regulatory mechanism between m^(6)A modification and GC development needs to be elucidated.In this study,we examined m^(6)A modification and the downstream mechanism in GC.Methods:Dot blotting assays,The Cancer Genome Atlas analysis,and quantitative real‑time PCR(qRT-PCR)were used to measure the m^(6)A levels in GC tissues.Methylated RNA-immunoprecipitation sequencing and RNA sequencingwere performed to identify the targets ofm^(6)Amodification.Western blotting,Transwell,wound healing,and angiogenesis assays were conducted to examine the role of centromere protein F(CENPF)in GC in vitro.Xenograft,immunohistochemistry,and in vivo metastasis experiments were conducted to examine the role of CENPF in GC in vivo.Methylated RNA-immunoprecipitation-qPCR,RNA immunoprecipitation-qPCR and RNA pulldown assays were used to verify the m^(6)A modification sites of CENPF.Gain/loss-of-function and rescue experiments were conducted to determine the relationship between CENPF and the mitogen-activated protein kinase(MAPK)signaling pathway in GC cells.Coimmunoprecipitation,mass spectrometry,qRT-PCR,and immunofluorescence assays were performed to explore the proteins that interact with CENPF and elucidate the regulatory mechanisms between them.Results:CENPF was upregulated in GC and facilitated the metastasis of GC both in vitro and in vivo.Mechanistically,increasedm^(6)A modification of CENPF was mediated by methyltransferase 3,and this modified molecule could be recognized by heterogeneous nuclear ribonucleoprotein A2/B1(HNRNPA2B1),thereby promoting its mRNA stability.In addition,the metastatic phenotype of CENPF was dependent on the MAPK signaling pathway.Furthermore,CENPF could bind to FAK and promote its localization in the cytoplasm.Moreover,we discovered that high expression of CENPF was related to lymphatic invasion and overall survival in GC patients.Conclusions:Our findings revealed that increased m^(6)A modification of CENPF facilitates the metastasis and angiogenesis of GC through the CENPF/FAK/MAPK and epithelial-mesenchymal transition axis.CENPF expression was correlated with the clinical features of GC patients;therefore,CENPF may serve as a prognostic marker of GC.

Inhibition of MYC suppresses programmed cell death ligand-1 expression and enhances immunotherapy in triple-negative breast cancer

Background:Cancer immunotherapy has emerged as a promising strategy against triple-negative breast cancer(TNBC).One of the immunosuppressive pathways involves programmed cell death-1(PD-1)and programmed cell death ligand-1(PD-L1),but many patients derived little benefit from PD-1/PD-L1 checkpoint blockades treatment.Prior research has shown that MYC,a master transcription amplifier highly expressed in TNBC cells,can regulate the tumor immune microenvironment and constrain the efficacy of immunotherapy.This study aims to investigate the regulatory relationship between MYC and PD-L1,and whether a cyclin-dependent kinase(CDK)inhibitor that inhibits MYC expression in combination with anti-PD-L1 antibodies can enhance the response to immunotherapy.Methods:Public databases and TNBC tissue microarrays were used to study the correlation between MYC and PD-L1.The expression of MYC and PD-L1 in TNBCs was examined by quantitative real-time polymerase chain reaction and Western blotting.A patient-derived tumor xenograft(PDTX)model was used to evaluate the influence of a CDK7 inhibitor THZ1 on PD-L1 expression.Cell proliferation and migration were detected by 5-ethynyl-2′-deoxyuridine(EdU)cell proliferation and cell migration assays.Tumor xenograft models were established for in vivo verification.Results:A high MYC expression level was associated with a poor prognosis and could alter the proportion of tumor-infiltrating immune cells(TIICs).The positive correlation between MYC and PD-L1 was confirmed by immunostaining samples from 165 TNBC patients.Suppression of MYC in TNBC caused a reduction in the levels of both PD-L1 messenger RNA and protein.In addition,antitumor immune response was enhanced in the TNBC cancer xenograft mouse model with suppression of MYC by CDK7 inhibitor THZ1.Conclusions:The combined therapy of CDK7 inhibitor THZ1 and anti-PD-L1 antibody appeared to have a synergistic effect,which might offer new insight for enhancing immunotherapy in TNBC.

Relationship of sleep duration and annual changes in sleep duration with the incidence of gastrointestinal cancers:a prospective cohort study

Background:Prospective analyses have yet to identify a consistent relationship between sleep duration and the incidence of gastrointestinal(GI)cancers.The effect of changes in sleep duration on GI cancer incidence has scarcely been studied.Therefore,we aimed to examine the association between baseline sleep duration and annual changes in sleep duration and GI cancer risk in a large population-based cohort study.Methods:A total of 123,495 participants with baseline information and 83,511 participants with annual changes in sleep duration information were prospectively observed from 2006 to 2015 for cancer incidence.Cox proportional-hazards models were used to calculate hazard ratios(HRs)and their confidence intervals(CIs)for GI cancers according to sleep duration and annual changes in sleep duration.Results:In baseline sleep duration analyses,short sleep duration(≤5 h)was significantly associated with a lower risk of GI cancer in females(HR:0.31,95%CI:0.10-0.90),and a linear relationship between baseline sleep duration and GI cancer was observed(P=0.010),especially in males and in the>50-year-old group.In the annual changes in sleep duration analyses,with stable category(0 to-15 min/year)as the control group,decreased sleep duration(≤-15 min/year)was significantly associated with the development of GI cancer(HR:1.29;95%CI:1.04-1.61),especially in the>50-year-old group(HR:1.32;95%CI:1.01-1.71),and increased sleep duration(>0 min/year)was significantly associated with GI cancer in females(HR:2.89;95%CI:1.14-7.30).Conclusions:Both sleep duration and annual changes in sleep duration were associated with the incidence of GI cancer.

Interdisciplinary management of central nervous system metastasis and neoplastic meningitis:recent developments and future perspectives

The incidence of metastatic disease in the central nervous system(CNS)is rising.According to current estimates,up to a third of adult cancer patients will suffer from CNS metastasis.Clinical evidence-based data from prospective randomized trials are rare,however,because CNS metastasis patients were often excluded from clinical trial participation.The management of CNS metastasis patients is therefore rather ill-defined and an interdisciplinary challenge.Recent basic and translational science data have begun contributing to a more profound understanding of the molecular mechanisms leading to invasion of tumor cells into the CNS.This report reviews advances,challenges,and perspectives in this field.