METTL5 promotes gastric cancer progression via sphingomyelin metabolism

BACKGROUND The treatment of gastric cancer(GC)has caused an enormous social burden worldwide.Accumulating studies have reported that N6-methyladenosine(m6A)is closely related to tumor progression.METTL5 is a m6A methyltransferase that plays a pivotal role in maintaining the metabolic stability of cells.However,its aberrant regulation in GC has not been fully elucidated.AIM To excavate the role of METTL5 in the development of GC.METHODS METTL5 expression and clinicopathological characteristics were analyzed via The Cancer Genome Atlas dataset and further verified via immunohistochemistry,western blotting and real-time quantitative polymerase chain reaction in tissue microarrays and clinical samples.The tumor-promoting effect of METTL5 on HGC-27 and AGS cells was explored in vitro by Cell Counting Kit-8 assays,colony formation assays,scratch healing assays,transwell assays and flow cytometry.The tumor-promoting role of METTL5 in vivo was evaluated in a xenograft tumor model.The EpiQuik m6A RNA Methylation Quantification Kit was used for m6A quantification.Next,liquid chromatography-mass spectrometry was used to evaluate the association between METTL5 and sphingomyelin metabolism,which was confirmed by Enzyme-linked immunosorbent assay and rescue tests.In addition,we investigated whether METTL5 affects the sensitivity of GC cells to cisplatin via colony formation and transwell experiments.RESULTS Our research revealed substantial upregulation of METTL5,which suggested a poor prognosis of GC patients.Increased METTL5 expression indicated distant lymph node metastasis,advanced cancer stage and pathological grade.An increased level of METTL5 correlated with a high degree of m6A methylation.METTL5 markedly promotes the proliferation,migration,and invasion of GC cells in vitro.METTL5 also promotes the growth of GC in animal models.METTL5 knockdown resulted in significant changes in sphingomyelin metabolism,which implies that METTL5 may impact the development of GC via sphingomyelin metabolism.In addition,high METTL5 expression led to cisplatin resistance.CONCLUSION METTL5 was found to be an oncogenic driver of GC and may be a new target for therapy since it facilitates GC carcinogenesis through sphingomyelin metabolism and cisplatin resistance.

miR-125b reverses cisplatin resistance by regulating autophagy via targeting RORA/BNIP3L axis in lung adenocarcinoma

The platinum-based chemotherapy is one of the most frequently used treatment protocols for lung adenocarcinoma(LUAD),and chemoresistance,however,usually results in treatment failure and limits its application in the clinic.It has been shown that microRNAs(miRNAs)play a significant role in tumor chemoresistance.In this study,miR-125b was identified as a specific cisplatin(DDP)-resistant gene in LUAD,as indicated by the bioinformatics analysis and the real-time quantitative PCR assay.The decreased serum level of miR-125b in LUAD patients was correlated with the poor treatment response rate and short survival time.MiR-125b decreased the A549/DDP proliferation,and the multiple drug resistance-and autophagy-related protein expression levels,which were all reversed by the inhibition of miR-125b.In addition,xenografts of human tumors in nude mice were suppressed by miR-125b,demonstrating that through autophagy regulation,miR-125b could reverse the DDP resistance in LUAD cells,both in vitro and in vivo.Further mechanistic studies indicated that miR-125b directly repressed the expression levels of RORA and its downstream BNIP3L,which in turn inhibited autophagy and reversed chemoresistance.Based on these findings,miR-125b in combination with DDP might be an effective treatment option to overcome DDP resistance in LUAD.

TGF-β-regulated different iron metabolism processes in the development and cisplatin resistance of ovarian cancer

The impact of different iron metabolism processes(DIMP)on ovarian cancer remains unclear.In this study,we employed various gene chips and databases to investigate the role of DIMP in the initiation and development of ovarian cancer.cBioPortal was used to determine mutations in DIMP-associated genes in ovarian cancer.Kaplan-Meier plotter was used to examine the influence of DIMP on the prognosis of ovarian cancer.By analyzing 1669 serous ovarian cancer cases,we identified a range of mutations in iron metabolism genes,notably in those coding for the transferrin receptor(19%),melanotransferrin(19%),and ceruloplasmin(10%)in the iron import process,and glucose-6-phosphate isomerase(9%),hepcidin antimicrobial peptide(9%),metal regulatory transcription factor 1(8%),and bone morphogenetic protein 6(8%)in the iron regulation process.Compared to the unaltered group,the group with gene alterations exhibited a higher tumor mutation burden count(43 vs.54)and more advanced histologic grade(78.19%vs.87.90%).Compared to the normal ovarian counterparts,a reduction in expression was observed in 9 out of the 14 genes involved in iron utilization and 4 out of the 5 genes involved in iron export in ovarian cancer;in contrast,an increase in expression was observed in 2 out of the 3 genes involved in iron storage in ovarian cancer.Furthermore,in cisplatin-resistant cells compared to cisplatin-sensitive ones,the expression of all genes in iron storage and 13 out of 14 genes in iron import was decreased,while that of 8 out of the 10 genes in iron utilization was increased.In addition,survival curve analysis indicated that a higher expression in the majority of genes in the iron import process(12/21),or a reduced expression in most genes in the iron export process(4/5)correlated with poor progression-free survival.Additionally,TGF-βcould regulate the expression of most iron metabolism-associated genes;particularly,expression of genes involved in the iron storage process(2/2)was inhibited after TGF-β1 or TGF-β2 treatment.In conclusion,DIMP plays multifaceted roles in the initiation,chemo-resistance,and prognosis of ovarian cancer.Therapeutically targeting DIMP may pave the way for more tailored treatment approaches for ovarian cancer.

Cisplatin-induced activation of TGF-βsignaling contributes to drug resistance

Growing evidence suggests an association between epithelial-mesenchymal transition(EMT),a hallmark of tumor malignancy,and chemoresistance to a number of anti-cancer drugs.However,the mechanism of EMT induction in the process of acquiring anti-cancer drug resistance remains unclear.To address this issue,we obtained a number of cisplatin-resistant clones from LoVo cells and found that almost all of them lost cell-cell contacts.In these clones,the epithelial marker E-cadherin was downregulated,whereas the mesenchymal marker N-cadherin was upregulated.Moreover,the expression of EMT-related transcription factors,including Slug,was elevated.On the other hand,the upregulation of other mesenchymal marker Vimentin was weak,suggesting that the mesenchymal-like phenotypic changes occurred in these cisplatin-resistant clones.These mesenchymal-like features of cisplatin-resistant clones were partially reversed to parental epithelial-like features by treatment with transforming growth factor-β(TGF-β)receptor kinase inhibitors,indicating that TGF-βsignaling is involved in cisplatin-induced the mesenchymallike phenotypic changes.Moreover,cisplatin was observed to enhance the secretion of TGF-βinto the culture media without influencing TGF-βgene transcription.These results suggest that cisplatin may induce the mesenchymal-like phenotypic changes by enhancing TGF-βsecretion,ultimately resulting in drug resistance.

Ganoboninketal C from Ganoderma boninense improves the efficacy of CDDP-based chemotherapy through inhibiting translesion DNA synthesis

Translesion DNA synthesis(TLS)can bypass DNA lesions caused by chemotherapeutic drugs,which usually result in drug resistance.Given its key role in mutagenesis and cell survival after DNA damage,inhibition of the TLS pathway has emerged as a potential target for improving the efficacy of DNA-damaging agents such as cisplatin(CDDP),a widely used anticancer agent.Unfortunately,few suitable natural TLS inhibitors have been reported.Here,we found that a triterpenoid compound Ganoboninketal C(26-3)from Ganoderma boninense,a traditional Chinese medicine,can impair CDDP-induced TLS polymerase eta(Polη)focus formation,PCNA monoubiquitination as well as mutagenesis.Moreover,26-3 can significantly sensitize tumor cells to CDDP killing and reduce the proportion of cancer stem cells in AGS and promote apoptosis after CDDP exposure.Interestingly,26-3 can also sensitize tumor cells to Gefitinib therapy.Mechanistically,through RNA-seq analysis,we found that 26-3 could abrogate the CDDP-induced upregulation of Polηand PIDD(p53-induced protein with a death domain),2 known factors promoting TLS pathway.Furthermore,we found that activating transcription factor 3 is a potential novel TLS modulator.Taken together,we have identified a natural TLS inhibitor 26-3,which can be potentially used as an adjuvant to improve clinical efficacy.

Liu-Jun-Zi decoction alleviates chemotherapy-induced anorexia by regulating gut microbiota and TLR4/MyD88/NF-κB p65 signaling pathway

Background:Liu-Jun-Zi decoction(LJZD),a classical nourishing formula in China,has been proven to be effective in treating chemotherapy-induced anorexia.In this study,the mechanism of LJZD in alleviating chemotherapy-induced anorexia was discussed from the aspects of regulating gut microbiota,repairing intestinal barrier injury and inhibiting inflammatory pathways.Methods:A rat model of chemotherapy-induced anorexia was established using cisplatin.The study evaluated the therapeutic effects of LJZD by observing the weight,food intake,and intestinal pathology of rats.The impact of LJZD on gut microbiota and metabolites,specifically short-chain fatty acids,was investigated through gut microbiota analysis and targeted metabolomics.The anti-inflammatory and intestinal protective effects of LJZD were assessed by examining the expression of intestinal tight junction proteins associated with the inflammatory pathway.Results:LJZD alleviated cisplatin-induced inflammation and intestinal barrier disruption,as evidenced by upregulated expression of tight junction protein 1(TJ-1)and occludin,along with reduced serum levels of interleukin 6(IL-6),interleukin-1β(IL-1β),tumor necrosis factor-α(TNF-α),and lipopolysaccharide.Additionally,LJZD alleviated microbiota imbalance and regulated the levels of short-chain fatty acids,especially increased the relative abundance of Coriobacteriales Incertae Sedis,Lactabacillus johnsonii F19785,Parasutterella,and reduced the Tyzzerella.In the hypothalamus,LJZD exerts suppressive effects on the toll-like receptor 4(TLR4)/myeloid differentiation factor 88(MyD88)/nuclear factor-κB(NF-κB)p65 signaling pathway,leading to a downregulation in the transcriptional activity of IL-6 and IL-1β,as well as Interleukin 6 receptors(IL-6R)and Interleukin-1βreceptors(IL-1R1)mRNA expression levels.Conclusion:In summary,LJZD alleviate chemotherapy-induced anorexia by modulating the gut microbiota,repairing the intestinal mechanical barriers,and suppressing the TLR4/MyD88/NF-κB p65 signaling pathway.

Celecoxib enhances the response of tumor cells to cisplatin through upregulating PUMA in non–small cell lung cancer carrying wild-type p53

Celecoxib,a cyclooxygenase-2 inhibitor,can enhance the efficacy of chemotherapy;however,its effect seems inconsistent.In this study,we investigated whether celecoxib would increase the antiproliferative effects of cisplatin in human lung cancer cells.Our data demonstrated the synergistic effects of celecoxib with cisplatin in wild-type p53 cells and their antagonistic effects inmutated or deleted p53 cells.Combination indices of 0.82 to 0.93 reflected a synergistic effect between celecoxib and cisplatin in lung cancer cells with wild-type p53.Combination indices of 1.63 to 3.00 reflected antagonism between celecoxib and cisplatin in lung cancer cells with mutated or deleted p53.Compared with that in cells with mutated or deleted p53,apoptosis significantly increased with the addition of celecoxib and cisplatin in wild-type p53 cells(P<0.05).Moreover,the results in vivo were similar to those in vitro:celecoxib combinedwith cisplatin slowed tumor growth in wild-type p53 groups and not in mutated or deleted p53 groups.In addition,celecoxib promoted p53 translocation into the nucleus and upregulated active p53 expression in wild-type p53 cells.Celecoxib combined with cisplatin upregulated PUMA(PUMA is a downstream gene of p53)after active p53 increased in wild-type p53 cells.In summary,the combination of celecoxib and cisplatin demonstrates clear synergistic effects in wild-type p53 cells and antagonistic effects inmutated or deleted p53 cells.The synergistic effect was achieved by apoptosis,induced by upregulating PUMA.Our results will provide a new treatment strategy for patients carrying wild-type p53,insensitive to cisplatin.

Management of Testicular Cancers in Brazzaville

Introduction: Testicular cancer accounts for 5% of urological tumors, predominantly affecting young men. The aim of our study was to report the diagnostic and evolutionary aspects of testicular cancer cases treated in our center. Patients and Methods: A retrospective study conducted over a 15-year period involving 12 patients treated for testicular cancer at the University Hospital of Brazzaville. Results: The median age was 31 years (range 11 to 49 years), with a median consultation delay of 10.6 months (range 3 to 27 months). Scrotal mass was the most common reason for consultation. Cancer was bilateral in two patients. Two patients were admitted with metastatic disease. Histopathological examination favored germ cell tumors in 7 cases, two cases of non-Hodgkin’s malignant lymphoma, and one case of epididymo-testicular adenocarcinoma. Adjuvant chemotherapy resulted in complete remission in patients with germ cell tumors. However, neoadjuvant chemotherapy was not effective in patients admitted with advanced-stage disease. Conclusion: Testicular cancer is a rare condition that is curable in the majority of cases, but its management is often complicated in our setting due to delayed diagnosis caused by taboos surrounding genital organ pathologies.

hucMSC-derived exosomes protect ovarian reserve and restore ovarian function in cisplatin treated mice

Anti-cancer therapy often causes premature ovarian insufficiency and infertility as the ovarian follicle reserve is extremely sensitive to chemotherapy drugs,such as cisplatin.Various fertility preservation methods have been explored for women,especially prepubertal girls undergoing radiotherapy and chemotherapy due to cancer.In recent years,mesenchymal stem cell-derived exosomes(MSC-exos)have been reported to play an important role in tissue repair and the treatment of various diseases.In the current study,we observed that human umbilical cord-derived MSC-exos(hucMSC-exos)after short-term culture improved follicular survival and development while receiving cisplatin treatment.Moreover,intravenous injection of hucMSC-exos improved ovarian function and ameliorated inflammatory environment within the ovary.The underlying mechanism of hucMSC-exos on fertility preservation was associated with the down-regulation of p53-related apoptosis and their anti-inflammatory function.Based on these findings,we propose that hucMSC-exos may be a potential approach to improve fertility in women diagnosed with cancer.

TMED2 Induces Cisplatin Resistance in Breast Cancer via Targeting the KEAP1-Nrf2 Pathway

Objective Cisplatin is the first-line treatment for breast cancer,but it faces challenges of drug resistance.This study investigated new molecular mechanisms underlying cisplatin resistance in breast cancer.Methods We analyzed sequencing data from the TCGA database to identify potential associations between transmembrane emp24 protein transport domain containing 2(TMED2)and breast cancer.Western blotting,real-time PCR,CCK-8,and TUNEL assays were used to measure the effects and molecular mechanism of TMED2 on cisplatin resistance in MCF-7 and MDA-MB-231 cell lines.Results TMED2 was overexpressed in breast cancer and associated with poor prognosis.TMED2 increased cisplatin resistance in breast cancer cells in vitro via promoting ubiquitination of Kelch-like ECH-associated protein 1(KEAP1),relieving inhibition of KEAP1 on nuclear factor erythroid 2-related factor 2(Nrf2),and increasing expression of downstream drug resistance related genes,such as heme oxygenase 1(HO-1)and NAD(P)H quinone oxidoreductase 1(NQO1).Conclusion We identified a new molecular mechanism by which TMED2 affects cisplatin resistance in breast cancer.Our results provide theoretical guidance for future clinical applications.

Ellagic acid ameliorates cisplatin-induced acute kidney injury by regulating inflammation and SIRT6/TNF-α signaling

De spite cisplatin has been widely used in the treatment of various cancers,the noteworthy nephrotoxicity greatly constrained its clinical value.For this reason,finding novel targeted therapies to attenuate the nephrotoxicity of cisplatin should be pretty significant.Our previous study found that histone deacetylase sirtuin 6(SIRT6)could be an ideal target for the treatment of cisplatin-induced acute kidney injury.In this study,we explored the protective effects of ellagic acid,a natural polyphenol compound that activates SIRT6,on cisplatin-induced nephrotoxicity.Pre-treatment of ellagic acid attenuated cytotoxicity of cisplatin in primary renal cells and TCMK-1 cells.Moreover,ellagic acid ameliorated renal dysfunction,apoptosis and fibrosis induced by cisplatin in mice.Furthermore,ellagic acid reduced nephrotoxicity-associated inflammatory factor interleukin(IL)-1βand IL-6 expression both in vitro and in vivo.Mechanistically,ellagic acid reversed cisplatin-reduced SIRT6 expression and diminished cisplatin-induced tumor necrosis factor(TNF)-αexpression.And SIRT6 knockdown abrogated the protective effects of ellagic acid on cisplatin-induced cell apoptosis,indicating the renal-protective effects of ellagic acid are mainly dependent on ellagic acid-mediated SIRT6 activation.Our results provide preclinical rationale for using ellagic acid as a feasible and promising agent to ameliorate cisplatin-induced acute kidney injury,and support ellagic acid as a potential adjunctive therapy for future cancer treatment.

PKD1抑制剂CID755673通过诱导线粒体功能障碍加重急性肾损伤

目的 探讨PKD1在急性肾损伤(acute kidney injury, AKI)中的表达及其作用机制。方法 采用免疫组化法检测癌旁正常肾组织和AKI患者肾活检组织中以及顺铂(Cisplatin)处理的小鼠肾组织中PKD1的表达;体外培养小鼠肾小管上皮细胞(mouse proximal tubular epithelial cells, mPTC),应用qRT-PCR和Western blot法检测PKD1及凋亡相关基因mRNA和蛋白表达水平;运用流式细胞术检测细胞凋亡、线粒体膜电位及线粒体活性氧水平。结果 免疫组化检测:PKD1在AKI患者肾活检组织中的表达(4.07±0.994)明显高于癌旁正常肾组织(1.001±0.073,P=0.021 1);在Cisplatin诱导的小鼠AKI肾组织中也发现,与对照组(0.992±0.072)相比,AKI肾组织中PKD1表达水平明显上调(2.457±0.317,P=0.002 5);在mPTC中,与Cisplatin组比较,Cisplatin+CID组中Bax mRNA及蛋白表达增加(P<0.05)及Caspase-3活化水平升高(P=0.026),抗凋亡蛋白BCL-2 mRNA及蛋白水平则进一步下调(P<0.05)。流式细胞术实验:与Cisplatin组比较,Cisplatin+CID组细胞凋亡百分比(Cisplatin组为21.77±2.378、Cisplatin+CID组为43.01±2.796,P<0.000 1)及线粒体活性氧水平(Cisplatin组为1.562±0.023、Cisplatin+CID组为1.957±0.088,P=0.002)进一步增加;而线粒体膜电位水平进一步降低(Cisplatin组为0.725 7±0.163、Cisplatin+CID组为0.46±0.026,P=0.043)。结论 PKD1在AKI损伤中显著上调,抑制PKD1明显加重Cisplatin诱导的AKI,其有望成为防治AKI的新靶点。

Theanine combined with cisplatin inhibits the proliferation and metastasis of TNBC cells through Akt signaling pathway

Background:Theanine,was natural compounds,has been employed in antibacterial,antineoplastic,promotion of hair growth,therapy of poliosis,and removing pattogenic heat from the blood and toxic material from the body for centuries.However,few reports focused on the treatment by theanine combined with chemotherapy in triple negative breast cancer.Methods:Our study aimed to evaluate and compare the molecular and cellular effects of theanine in combination with cisplatin in triple negative breast cancer lines MDA-MB-231.The 50%inhibitory concentration and cell viability were determined by the cell counting kit-8 assay.Meanwhile,wound healing and transwell assays were used to evaluate the effect of theanine combination with cisplatin on triple negative breast cancer(TNBC)cell metastasis.Moreover,the label-free proteomic method was available to explore the molecular mechanism of theanine combination with cisplatin on TNBC cells.What’s more,reverse transcription-polymerase chain reaction and western blotting were carried out to evaluate the related protein and mRNA alteration in the Akt signaling pathway.Results:With theanine added,the inhibitory effect of cisplatin on cell proliferation and metastasis was significantly improved.Meanwhile,with the increase of theanine concentration,the anti-tumor effect of the combination group was also significantly improved.Afterward,label-free proteomics analysis showed that theanine combined with cisplatin could significantly activate the Akt signaling pathway,thus improving the anti-tumor effect of cisplatin.Finally,reverse transcription-polymerase chain reaction and western blotting experiment showed that the combination of cisplatin with theanine induced the greatest down-regulation of phosphorylated Akt expression.Conclusion:All in all,combining theanine with appears to be a promising strategy for the effective treatment of TNBC in the prospective application which merits further clinical investigation.

Elevated extracellular calcium ions accelerate the proliferation and migration of HepG2 cells and decrease cisplatin sensitivity

Hepatoblastoma is the most frequent liver malignancy in children.HepG2 has been discovered as a hepatoblastoma-derived cell line and tends to form clumps in culture.Intriguingly,we observed that the addition of calcium ions reduced cell clumping and disassociated HepG2 cells.The calcium signal is in connection with a series of processes critical in the tumorigenesis.Here,we demonstrated that extracellular calcium ions induced morphological changes and enhanced the epithelial-mesenchymal transition in HepG2 cells.Mechanistically,calcium ions promoted HepG2 proliferation and migration by up-regulating the phosphorylation levels of focal adhesion kinase(FAK),protein kinase B,and p38 mitogen-activated protein kinase.The inhibitor of FAK or Ca2+/calmodulin-dependent kinaseⅡ(CaMKⅡ)reversed the Ca2+-induced effects on HepG2 cells,including cell proliferation and migration,epithelial-mesenchymal transition protein expression levels,and phosphorylation levels of FAK and protein kinase B.Moreover,calcium ions decreased HepG2 cells'sensitivity to cisplatin.Furthermore,we found that the expression levels of FAK and CaMKⅡwere increased in hepatoblastoma.The group with high expression levels of FAK and CaMKⅡexhibited significantly lower ImmunoScore as well as CD8+T and NK cells.The expression of CaMKⅡwas positively correlated with that of PDCD1 and LAG3.Correspondingly,the expression of FAK was negatively correlated with that of TNFSF9,TNFRSF4,and TNFRSF18.Collectively,extracellular calcium accelerates HepG2 cell proliferation and migration via FAK and CaMKⅡand enhances cisplatin resistance.FAK and CaMKⅡshape immune cell infiltration and responses in tumor microenvironments,thereby serving as potential targets for hepatoblastoma.

Deciphering key genes involved in cisplatin resistance in kidney renal clear cell carcinoma through a combined in silico and in vitro approach

The low survival rate of Kidney renal clear cell carcinoma(KIRC)patients is largely attributed to cisplatin resistance.Rather than focusing solely on individual proteins,exploring protein-protein interactions could offer greater insight into drug resistance.To this end,a series of in silico and in vitro experiments were conducted to identify hub genes in the intricate network of cisplatin resistance-related genes in KIRC chemotherapy.The genes involved in cisplatin resistance across KIRC were retrieved from the National Center for Biotechnology Information(NCBI)database using search terms as“Kidney renal clear cell carcinoma”and“Cisplatin resistance”.The genes retrieved were analyzed for hub gene identification using the STRING database and Cytoscape tool.Expression and promoter methylation profiling of the hub genes was done using UALCAN,GEPIA,OncoDB,and HPA databases.Mutational,survival,functional enrichment,immune cell infiltration,and drug prediction analyses of the hub genes were performed using the cBioPortal,GEPIA,GSEA,TIMER,and DrugBank databases.Lastly,expression and methylation levels of the hub genes were validated on two cisplatin-resistant RCC cell lines(786-O and A-498)and a normal renal tubular epithelial cell line(HK-2)using two high throughput techniques,including targeted bisulfite sequencing(bisulfite-seq)and RT-qPCR.A total of 124 genes were identified as being associated with cisplatin resistance in KIRC.Out of these genes,MCL1,IGF1R,CCND1,and PTEN were identified as hub genes and were found to have significant(p<0.05)variations in their mRNA and protein expressions and effects on the overall survival(OS)of the KIRC patients.Moreover,an aberrant promoter methylation pattern was found to be associated with the dysregulation of the hub genes.In addition to this,hub genes were also linked with different cisplatin resistance-causing pathways.Thus,hub genes can be targeted with Alvocidib,Estradiol,Tretinoin,Capsaicin,Dronabinol,Metribolone,Calcitriol,Acetaminophen,Acitretin,Cyclosporine,Azacitidine,Genistein,and Resveratrol drugs.As the pathogenesis of KIRC is complex,targeting hub genes and associated pathways involved in cisplatin resistance could bring a milestone change in the drug discovery and management of drug resistance,which might uplift overall survival among KIRC patients.

Inhibition of histone methyltransferase PRMT5 attenuates cisplatininduced hearing loss through the PI3K/Akt-mediated mitochondrial apoptotic pathway

This study aimed to evaluate the therapeutic potential of inhibiting protein arginine methyltransferase 5(PRMT5)in cisplatin-induced hearing loss.The effects of PRMT5 inhibition on cisplatin-induced auditory injury were determined using immunohistochemistry,apoptosis assays,and auditory brainstem response.The mechanism of PRMT5 inhibition on hair cell survival was assessed using RNA-seq and Cleavage Under Targets and Tagment-quantitative polymerase chain reaction(CUT&Tag-qPCR)analyses in the HEI-OC1 cell line.Pharmacological inhibition of PRMT5 significantly alleviated cisplatin-induced damage to hair cells and spiral ganglion neurons in the cochlea and decreased apoptosis by protecting mitochondrial function and preventing the accumulation of reactive oxygen species.CUT&Tag-qPCR analysis demonstrated that inhibition of PRMT5 in HEI-OC1 cells reduced the accumulation of H4R3me2s/H3R8me2s marks at the promoter region of the Pik3ca gene,thus activating the expression of Pik3ca.These findings suggest that PRMT5 inhibitors have strong potential as agents against cisplatininduced ototoxicity and can lay the foundation for further research on treatment strategies of hearing loss.

Erratum to:ARID1A Inactivation Increases Expression of circ0008399 and Promotes Cisplatin Resistance in Bladder Cancer

The original version of this article was revised due to production error by the vendor.The author“Hua-min DING”is one of the co-authors,and the name should be labeled correctly as appears on PDF.The affiliation of“Yu-jun SHUAI”and“Chao HUANG”is“Department of Urology,Union Hospital,Tongji Medical College,Huazhong University of Science and Technology,Wuhan 430022,China”,and both of them should be labeled as 1,as correctively appears on PDF.

A nanocomposite competent to overcome cascade drug resistance in ovarian cancer via mitochondria dysfunction and NO gas synergistic therapy

Ovarian cancer(OC)is one of the most common and recurring malignancies in gynecology.Patients with relapsed OC always develop"cascade drug resistance"(CDR)under repeated chemotherapy,leading to subsequent failure of chemotherapy.To overcome this challenge,amphiphiles(P1)carrying a nitric oxide(NO)donor(Isosorbide 5-mononitrate,ISMN)and high-density disulfide are synthesized for encapsulatingmitochondria-targeted tetravalent platinum prodrug(TPt)to construct a nanocomposite(INP@TPt).Mechanism studies indicated that INP@TPt significantly inhibited drug-resistant cells by increasing cellular uptake and mitochondrial accumulation of platinum,depleting glutathione,and preventing apoptosis escape through generating highly toxic peroxynitrite anion(ONOO−).To better replicate the microenvironmental and histological characteristics of the drug resistant primary tumor,an OC patient-derived tumor xenograft(PDXOC)model in BALB/c nude mice was established.INP@TPt showed the best therapeutic effects in the PDXOC model.The corresponding tumor tissues contained high ONOO−levels,which were attributed to the simultaneous release of O_(2)^(·−)and NO in tumor tissues.Taken together,INP@TPtbased systematic strategy showed considerable potential and satisfactory biocompatibility in overcoming platinum CDR,providing practical applications for ovarian therapy.

Deltonin enhances gastric carcinoma cell apoptosis and chemosensitivity to cisplatin via inhibiting PI3K/AKT/mTOR and MAPK signaling

BACKGROUND As an active ingredient derived from Dioscorea zingiberensis C.H.Wright,deltonin has been reported to show anti-cancer effects in a variety of malignancies.AIM To investigate the role and mechanism of action of deltonin in promoting gastric carcinoma(GC)cell apoptosis and chemosensitivity to cisplatin.METHODS The GC cell lines AGS,HGC-27,and MKN-45 were treated with deltonin and then subjected to flow cytometry and 3-(4,5-dimethylthiazol-2-yl)-3,5-diphenyltet-razolium bromide assays for cell apoptosis and viability determination.Western blot analysis was conducted to examine alterations in the expression of apoptosis-related proteins(Bax,Bid,Bad,and Fas),DNA repair-associated proteins(Rad51 and MDM2),and phosphatidylinositol 3-kinase/protein kinase B/mammalian target of the rapamycin(PI3K/AKT/mTOR)and p38-mitogen-activated protein kinase(MAPK)axis proteins.Additionally,the influence of deltonin on GC cell chemosensitivity to cisplatin was evaluated both in vitro and in vivo.RESULTS Deltonin treatment weakened viability,enhanced apoptosis,and dampened DNA repair in GC cell lines in a dose-dependent pattern.Furthermore,deltonin mitigated PI3K,AKT,mTOR,and p38-MAPK phosphorylation.HS-173,an inhibitor of PI3K,attenuated GC cell viability and abolished deltonin inhibition of GC cell viability and PI3K/AKT/mTOR and p38-MAPK pathway activation.Deltonin also promoted the chemosensitivity of GC cells to cisplatin via repressing GC cell proliferation and growth and accelerating apoptosis.CONCLUSION Deltonin can boost the chemosensitivity of GC cells to cisplatin via inactivating p38-MAPK and PI3K/AKT/mTOR signaling.

Flavonoids in safflower extract reduce cisplatin-induced damage to human follicle dermal papilla cells by inhibiting DNA damage and Rad17/Chk1/Cdc25C signaling

Background:Cisplatin is a chemotherapeutic agent commonly used clinically for the treatment of various human cancers.Patients often reduce the use of cisplatin due to its side effects,which in turn affects its treatment.This study explored the mechanism of action of safflower extract as an adjuvant traditional Chinese medicine for chemotherapy.Methods:Primary human follicle dermal papilla cells(HFDPCs)were used as target cells for cisplatininduced damage to hair cells.Western blotting was used to investigate the molecular targets of cisplatin and safflower extract in causing HFDPCs damage.Cell survival and cell cycle were analyzed by mitochondrial staining reagent WST-1 and propidium iodide.Results:Cisplatin could reduce the viability of HFDPCs without causing cell death.Cisplatin increased the level of phospho-Rad17 in HFDPCs and activated the Chk1/Cdc25C signaling to reduce the expression of Cdc2 protein,thereby arresting the cells in the G2/M phase.The combination of safflower extract and the flavonoids could effectively inhibit the signal transduction of Rad17/Chk1/Cdc25 in cisplatin-treated cells and reduce the cell population in the G2/M phase.Finally,we also confirmed that safflower extract could effectively inhibit the damage to HFDPCs caused by cisplatin,mainly at the level of reducing the DNA damage caused by cisplatin.Conclusions:Safflower extract can be used as an adjuvant Chinese medicine for chemotherapy to reduce the damage caused by chemotherapy to normal hair follicle cells.