Development Of Cisplatin Resistance Research Articles

Establishment and characterization of cisplatin-resistant cell lines from canine mammary gland tumors

The development of cisplatin resistance is one of the major causes of mammary cancer treatment failure, and is associated with changes in Sox4 gene expression. To investigate the characteristic changes that occur in canine mammary gland tumor (CMGT) cells following the development of acquired cisplatin resistance, along with the relationship between these changes and the Sox4 gene. We constructed cisplatin-resistant cell line, CHMpCIS, from the cell line CHMp, which was isolated from the primary lesion of a malignant CMGT. The biological characteristics of these cells were examined by Western blot analysis, Transwell assays, and mammosphere formation assays. Compared to CHMp cells, CHMpCIS cells exhibited elevated cisplatin resistance, apoptotic escape ability, enhanced epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) features, in addition to over-activation of the Wnt/β-catenin signaling pathway and increased Sox4 protein. In CMGT cases, CMGT tissues (CMGTT) expressed higher levels of Sox4 protein and mRNA compared to adjacent tissues (CAMGTT). We found that these changes were inhibited by silencing of Sox4 expression in CHMpCIS cells. Furthermore, activation of the Wnt/β-catenin signaling pathway increased Sox4 expression levels through a positive feedback loop. These results suggested that CHMpCIS cells circumvented the damage caused by cisplatin through altering the expression of the Sox4 gene and activating the Wnt/β-catenin pathway, thereby changing the cellular biological characteristics.

P32/OPA1 axis-mediated mitochondrial dynamics contributes to cisplatin resistance in non-small cell lung cancer.

Cisplatin resistance is a major obstacle in the treatment of non-small cell lung cancer (NSCLC). p32 and OPA1 are the key regulators of mitochondrial morphology and function. This study aims to investigate the role of the p32/OPA1 axis in cisplatin resistance in NSCLC and its underlying mechanism. The levels of p32 protein and mitochondrial fusion protein OPA1 are higher in cisplatin-resistant A549/DDP cells than in cisplatin-sensitive A549 cells, which facilitates mitochondrial fusion in A549/DDP cells. In addition, the expression of p32 and OPA1 protein is also upregulated in A549 cells during the development of cisplatin resistance. Moreover, p32 knockdown effectively downregulates the expression of OPA1, stimulates mitochondrial fission, decreases ATP generation and sensitizes A549/DDP cells to cisplatin-induced apoptosis. Furthermore, metformin significantly downregulates the expressions of p32 and OPA1 and induces mitochondrial fission and a decrease in ATP level in A549/DDP cells. The co-administration of metformin and cisplatin shows a significantly greater decrease in A549/DDP cell viability than cisplatin treatment alone. Moreover, D-erythro-Sphingosine, a potent p32 kinase activator, counteracts the metformin-induced downregulation of OPA1 and mitochondrial fission in A549/DDP cells. Taken together, these findings indicate that p32/OPA1 axis-mediated mitochondrial dynamics contributes to the acquired cisplatin resistance in NSCLC and that metformin resensitizes NSCLC to cisplatin, suggesting that targeting p32 and mitochondrial dynamics is an effective strategy for the prevention of cisplatin resistance.

Meta-analysis of microarray data to determine gene indicators involved in the cisplatin resistance in ovarian cancer.

Significant miss-expressed gene indicators contributing to cisplatin resistance in ovarian cancer have not been completely understood. It seems that several regulatory genes and signaling pathways are associated with the emergence of the chemo-resistant phenotype. Here, a meta-analysis approach was adopted to assess deregulated genes involved in relapse after the first line of chemotherapy (cisplatin). To do so, six ovarian cancer libraries were gathered from GEO repository. Batch effect removal and quality assessment, and boxplots and PCA were performed using SVA and ggplot2 packages in R, respectively. Cisplatin-resistant and -sensitive ovarian cancer groups were compared with find genes with significant expression changes using linear regression models in the LIMMA R package. The significance threshold for DEGs was taken as adj p-value < .05 and - 1 > logFC > 1. A total of 261 genes were identified to have significant differential expression levels in the cisplatin-resistant versus cisplatin-sensitive group. Among the 10 top up-regulated and down-regulated genes, PITX2, SNCA, and EPHA7 (up), as well as TMEM98 (down) are indirect upstream regulators of PI3K/AKT signaling pathway, contributing greatly to the development of chemo-resistance in cancer via promoting cell proliferation, survival, and cell cycle progression as well as inhibiting apoptosis. Moreover, a comprehensive assessment of DEGs revealed the dysregulation of not only membrane ion channels KCa1.1, Kv4, and CACNB4, affecting cell excitability, proliferation, and apoptosis but also cell adhesion proteins COL4A6, EPHA3, and CD9, affecting the attachment of normal cells to ECM and apoptosis, introducing good options to reverse cisplatin resistance. Our results predict and suggest that upstream regulators of PI3K/AKT signaling pathway, ion channels, and cell adhesion proteins play important roles in cisplatin resistance development in ovarian cancer.

MiR-375 promotes cisplatin sensitivity of lung adenocarcinoma

BackgroundCisplatin-based chemotherapy has been widely used in the treatment of lung adenocarcinoma (LUAD). However, the development of cisplatin resistance becomes a major obstacle impeding the curative effect. It remains necessary to uncover the molecular mechanism of cisplatin resistance. MethodsBased on the CCLE database, lung cancer cell lines were divided into cisplatin-resistant and cisplatin-sensitive groups. The differentially expressed miRNAs were filtered and further identified by survival prognosis analysis. After transfection with miR-375 inhibitor or mimic, cell cytotoxicity assay, flow cytometry and western blot were conducted to validate the role of miR-375. The transcription factor (TF)-miRNA network was constructed based on TransmiR. The target genes of miR-375 were predicted by Starbase and further verified by RT-qPCR and immunohistochemistry results in the Human Protein Atlas. Functional enrichment analysis was performed with GO terms and KEGG. ResultsIn this study, miR-375 showed the ability to promote cisplatin sensitivity and apoptosis of LUAD. Genes correlated with miR-375 in LUAD were analyzed and ABCC8 showed the strongest positive correlation. Moreover, transcription factors that regulate miR-375 expression were predicted. MBNL1, PTPN3, PRKD1 and RPN1 were identified as the target genes of miR-375. Enrichment analysis demonstrated that miR-375-related genes associated with promoting cell proliferation and anti-apoptosis were involved in the MAPK signaling pathway. ConclusionOverall, this study provides new insights into the role of miR-375 in the cisplatin sensitivity of LUAD. Our present findings may serve as a theoretical basis for new therapeutic strategies and predictive models of cisplatin resistance in LUAD.

Isoalantolactone Suppresses Glycolysis and Resensitizes Cisplatin-Based Chemotherapy in Cisplatin-Resistant Ovarian Cancer Cells.

Cisplatin is a potent chemotherapeutic drug for ovarian cancer (OC) treatment. However, its efficacy is significantly limited due to the development of cisplatin resistance. Although the acquisition of cisplatin resistance is a complex process involving various molecular alterations within cancer cells, the increased reliance of cisplatin-resistant cells on glycolysis has gained increasing attention. Isoalantolactone, a sesquiterpene lactone isolated from Inula helenium L., possesses various pharmacological properties, including anticancer activity. In this study, isoalantolactone was investigated as a potential glycolysis inhibitor to overcome cisplatin resistance in OC. Isoalantolactone effectively targeted key glycolytic enzymes (e.g., lactate dehydrogenase A, phosphofructokinase liver type, and hexokinase 2), reducing glucose consumption and lactate production in cisplatin-resistant OC cells (specifically A2780 and SNU-8). Importantly, it also sensitized these cells to cisplatin-induced apoptosis. Isoalantolactone-cisplatin treatment regulated mitogen-activated protein kinase and AKT pathways more effectively in cisplatin-resistant cells than individual treatments. In vivo studies using cisplatin-sensitive and resistant OC xenograft models revealed that isoalantolactone, either alone or in combination with cisplatin, significantly suppressed tumor growth in cisplatin-resistant tumors. These findings highlight the potential of isoalantolactone as a novel glycolysis inhibitor for treating cisplatin-resistant OC. By targeting the dysregulated glycolytic pathway, isoalantolactone offers a promising approach to overcoming drug resistance and enhancing the efficacy of cisplatin-based therapies.

Pevonedistat Inhibits SOX2 Expression and Sphere Formation but Also Drives the Induction of Terminal Differentiation Markers and Apoptosis within Arsenite-Transformed Urothelial Cells.

Urothelial cancer (UC) is a common malignancy and its development is associated with arsenic exposure. Around 25% of diagnosed UC cases are muscle invasive (MIUC) and are frequently associated with squamous differentiation. These patients commonly develop cisplatin (CIS) resistance and have poor prognosis. SOX2 expression is correlated to reduced overall and disease-free survival in UC. SOX2 drives malignant stemness and proliferation in UC cells and is associated with development of CIS resistance. Using quantitative proteomics, we identified that SOX2 was overexpressed in three arsenite (As3+)-transformed UROtsa cell lines. We hypothesized that inhibition of SOX2 would reduce stemness and increase sensitivity to CIS in the As3+-transformed cells. Pevonedistat (PVD) is a neddylation inhibitor and is a potent inhibitor of SOX2. We treated non-transformed parent and As3+-transformed cells with PVD, CIS, or in combination and monitored cell growth, sphere forming abilities, apoptosis, and gene/protein expression. PVD treatment alone caused morphological changes, reduced cell growth, attenuated sphere formation, induced apoptosis, and elevated the expression of terminal differentiation markers. However, the combined treatment of PVD with CIS significantly elevated the expression of terminal differentiation markers and eventually led to more cell death than either solo treatment. Aside from a reduced proliferation rate, these effects were not seen in the parent. Further research is needed to explore the potential use of PVD with CIS as a differentiation therapy or alternative treatment for MIUC tumors that may have become resistant to CIS.

7-Epitaxol induces apoptosis in cisplatin-resistant head and neck squamous cell carcinoma via suppression of AKT and MAPK signalling.

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Although cisplatin-based chemotherapy is commonly used in HNSCC, frequent development of cisplatin resistance is a potential cause of poor HNSCC prognosis. In the present study, we investigated the anticancer efficacy of a major paclitaxel metabolite namely 7-Epitaxol in cisplatin-resistant HNSCC. The findings revealed that 7-Epitaxol exerts cytotoxic effects in cisplatin-resistant HNSCC cell lines by inducing cell cycle arrest and intrinsic and extrinsic apoptotic pathways. Specifically, 7-Epitaxol increased Fas, TNF-R1, DR5, DcR3 and DcR2 expressions, reduced Bcl-2 and Bcl-XL (anti-apoptotic proteins) expressions, and increased Bid and Bim L/S (pre-apoptotic proteins) expressions, leading to activation of caspase-mediated cancer cell apoptosis. At the upstream cell signalling level, 7-Epitaxol reduced the phosphorylation of AKT, ERK1/2 and p38 to trigger apoptosis. In vivo results showed that animals treated with 7-Epitaxol show antitumor growth compared to control animals. Taken together, the study demonstrates the potential anticancer efficacy of 7-Epitaxol in inducing apoptosis of cisplatin-resistant HNSCC cells through the suppression of AKT and MAPK signalling pathways.

Combinatorial Treatment with PARP-1 Inhibitors and Cisplatin Attenuates Cervical Cancer Growth through Fos-Driven Changes in Gene Expression.

Our observations, which link the gene regulatory effects of PARPi + cisplatin to the growth inhibitory effects of FOS expression in cervical cancer cells, strengthen the rationale for using PARPi with cisplatin as a therapy for cervical cancer.

PD51-03 MOLECULAR CHARACTERISTICS OF METASTATIC TERATOMAS AND MATCHED PRIMARY TESTICULAR GERM CELL TUMORS

You have accessJournal of UrologyCME1 May 2022PD51-03 MOLECULAR CHARACTERISTICS OF METASTATIC TERATOMAS AND MATCHED PRIMARY TESTICULAR GERM CELL TUMORS Anna Savelyeva, Feng Wang, Lei Guo, John Lafin, Liwei Jia, Kirill Medvedev, Cheryl Lewis, Payal Kapur, Vitaly Margulis, Solomon Woldu, Xiaosong Meng, Nick Grishin, James Amatruda, Lin Xu, and Aditya Bagrodia Anna SavelyevaAnna Savelyeva More articles by this author , Feng WangFeng Wang More articles by this author , Lei GuoLei Guo More articles by this author , John LafinJohn Lafin More articles by this author , Liwei JiaLiwei Jia More articles by this author , Kirill MedvedevKirill Medvedev More articles by this author , Cheryl LewisCheryl Lewis More articles by this author , Payal KapurPayal Kapur More articles by this author , Vitaly MargulisVitaly Margulis More articles by this author , Solomon WolduSolomon Woldu More articles by this author , Xiaosong MengXiaosong Meng More articles by this author , Nick GrishinNick Grishin More articles by this author , James AmatrudaJames Amatruda More articles by this author , Lin XuLin Xu More articles by this author , and Aditya BagrodiaAditya Bagrodia More articles by this author View All Author Informationhttps://doi.org/10.1097/JU.0000000000002622.03AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookLinked InTwitterEmail Abstract INTRODUCTION AND OBJECTIVE: Metastatic teratoma (MT) is a subtype of germ cell tumor (GCT) characterized by resistance to platinum-based chemotherapy. MT is treated via complete surgical excision, using retroperitoneal lymph node dissection (RPLND), following chemotherapy. Molecular characterization of post-chemotherapy MTs along with pre-chemotherapy testicular primary tumors could reveal 1) the mechanisms of MT development and differentiation, 2) molecular changes associated with platinum-resistance, 3) novel therapeutic options for patients with unresectable MTs. METHODS: We performed whole exome and transcriptome sequencing for 16 primary germ cell tumors and 18 metastatic teratomas, 11 were matched tumor/metastasis pairs. All MTs in our cohort were collected after induction platinum-based chemotherapy. We used VarScan for SNV analysis and PennCNV to detect genomic copy-number variations (CNVs). Metastatic Teratomas were compared to matched primary tumors and primary teratomas characterized by TCGA. RESULTS: Our analysis revealed that metastatic teratomas as well as their tumors of origin had low tumor mutation burden (0.65 and 0.47 accordingly). Amongst 583 SNVs detected in the study cohort, only two (KRAS p.Gly12Asp and KRAS p.Gly12Val) were previously described as oncogenic. Analysis of SNVs in proteins playing key roles in oncogenic signaling showed that TP53 and Ras pathways were the most affected in metastatic teratomas. The majority of metastatic teratomas possess gain of 3p11.1 and loss of 10q26.3, 16p11.2, 19p13.2, 19q12 and 22q12.3 loci. Within 3p11.1 we did not identify any well-known oncodrivers. However, 5 chromosomal loci with lost heterozygosity contained 16 previously annotated tumor suppressor genes: HTRA1, EBF3, FUS, PRKCB, NUPR1, PYCARD, ZNF668, ARMC5, YPEL3, DNMT1, DNAJB1, SMARCA4, GADD45GIP1, MIR199A1, TIMP3, TMPRSS6. Amongst those, GADD45GIP1 inhibition (growth arrest and DNA-damage-inducible, gamma interacting protein 1) is associated with cisplatin resistance development through mechanism of cellular senescence. CONCLUSIONS: Metastatic teratoma in our cohort is characterized by low tumor mutational burden and several recurring copy number changes. Molecular insight of metastatic teratoma may inform disease biology and treatment. Source of Funding: Dedman Scholar Award © 2022 by American Urological Association Education and Research, Inc.FiguresReferencesRelatedDetails Volume 207Issue Supplement 5May 2022Page: e843 Advertisement Copyright & Permissions© 2022 by American Urological Association Education and Research, Inc.MetricsAuthor Information Anna Savelyeva More articles by this author Feng Wang More articles by this author Lei Guo More articles by this author John Lafin More articles by this author Liwei Jia More articles by this author Kirill Medvedev More articles by this author Cheryl Lewis More articles by this author Payal Kapur More articles by this author Vitaly Margulis More articles by this author Solomon Woldu More articles by this author Xiaosong Meng More articles by this author Nick Grishin More articles by this author James Amatruda More articles by this author Lin Xu More articles by this author Aditya Bagrodia More articles by this author Expand All Advertisement PDF DownloadLoading ...

Piperlongumine increases the sensitivity of bladder cancer to cisplatin by mitochondrial ROS.

BackgroundThe development of cisplatin resistance often results in cisplatin inefficacy in advanced or recurrent bladder cancer. However, effective treatment strategies for cisplatin resistance have not been well established.MethodsGene expression was measured by qRT‐PCR and Western blotting. CCK‐8 assay was performed to detect cell survival. The number of apoptotic cells was determined using the Annexin V‐PI double‐staining assay. The level of reactive oxygen species (ROS) was measured using 2’,7'‐dichlorodihydrofluorescein diacetate fluorescent dye, and the ATP level was detected using an ATP measurement kit.ResultsThe expression of receptor‐interacting protein kinase 1 (RIPK1), a key regulator of necroptosis, gradually decreased during cisplatin resistance. We first used piperlongumine (PL) in combination with cisplatin to act on cisplatin‐resistant BC cells and found that PL‐induced activation of RIPK1 increased the sensitivity of T24 resistant cells to cisplatin treatment. Furthermore, we revealed that PL killed T24 cisplatin‐resistant cells by triggering necroptosis, because cell death could be rescued by the mixed lineage kinase domain‐like (MLKL) protein inhibitor necrotic sulfonamide or MLKL siRNA, but could not be suppressed by the apoptosis inhibitor z‐VAD. We further explored the specific mechanism and found that PL activated RIPK1 to induce necroptosis in cisplatin‐resistant cells by stimulating mitochondrial fission to produce excessive ROS.ConclusionsOur results demonstrated the role of RIPK1 in cisplatin‐resistant cells and the sensitization effect of the natural drug PL on bladder cancer. These may provide a new treatment strategy for overcoming cisplatin resistance in bladder cancer.

Overcoming Chemotherapy Resistance in Germ Cell Tumors.

Testicular germ cell tumors (GCTs) are highly curable malignancies. Excellent survival rates in patients with metastatic disease can be attributed to the exceptional sensitivity of GCTs to cisplatin-based chemotherapy. This hypersensitivity is probably related to alterations in the DNA repair of cisplatin-induced DNA damage, and an excessive apoptotic response. However, chemotherapy fails due to the development of cisplatin resistance in a proportion of patients. The molecular basis of this resistance appears to be multifactorial. Tracking the mechanisms of cisplatin resistance in GCTs, multiple molecules have been identified as potential therapeutic targets. A variety of therapeutic agents have been evaluated in preclinical and clinical studies. These include different chemotherapeutics, targeted therapies, such as tyrosine kinase inhibitors, mTOR inhibitors, PARP inhibitors, CDK inhibitors, and anti-CD30 therapy, as well as immune-checkpoint inhibitors, epigenetic therapy, and others. These therapeutics have been used as single agents or in combination with cisplatin. Some of them have shown promising in vitro activity in overcoming cisplatin resistance, but have not been effective in clinical trials in refractory GCT patients. This review provides a summary of current knowledge about the molecular mechanisms of cisplatin sensitivity and resistance in GCTs and outlines possible therapeutic approaches that seek to overcome this chemoresistance.

ARL6IP5 reduces cisplatin-resistance by suppressing DNA repair and promoting apoptosis pathways in ovarian carcinoma

Ovarian carcinoma (OC) is the most lethal gynecological malignancy due to frequent recurrence resulting from cisplatin-resistance. ARL6IP5 is a novel gene implicated to suppress cisplatin-resistance by activating apoptosis and inhibiting DNA repair through XRCC1 and PARP1. We investigated the clinicopathological and prognostic significance of the immunohistochemical ARL6IP5 expression on 79 post-chemotherapy OC patient tissue samples; in vitro, the effect of ARL6IP5 overexpression (OE) and knockdown (KD) on cancer hallmark functions and the effect of ARL6IP5 on the expression of DNA repair and apoptosis-related proteins were observed in OC cells and their cisplatin-resistant (CisR) counterparts. ARL6IP5 expression was significantly associated with chemotherapeutic response and was an independent prognosticator of progression-free and overall survival of high-grade serous OC patients. ARL6IP5-OE decreased cellular proliferation, invasion, migration, adhesion, and increased apoptosis (p < 0.05); the opposite was observed for ARL6IP5-KD. Notably, ARL6IP5-OE reduced cisplatin-resistance of both OC and CisR OC cells, while ARL6IP5-KD increased cisplatin-resistance (p < 0.05). ARL6IP5-OE suppressed the expressions of DNA repair proteins and increased those of pro-apoptotic proteins; the opposite was observed for ARL6IP5-KD. The recombinant ARL6IP5 protein (rARL6IP5) had the greatest apoptotic effect among cisplatin and olaparib, in both OC and CisR OC cells; moreover, rARL6IP5 was the only single agent in CisR OC cells to retain higher apoptotic efficacy compared with control (p < 0.05), indicating that the apoptotic pathway influenced by rARL6IP5 remained effective in CisR OC cells compared to cisplatin and olaparib. In conclusion, we demonstrated that ARL6IP5 is an independent prognosticator of OC patients with cellular functions of a tumor-suppressor, possibly influencing the development of cisplatin-resistance and progression of OC cells through regulation of DNA repair and apoptosis. rARL6IP5 had significantly greater apoptotic efficacy compared to conventional chemotherapeutic agents in both OC and CisR OC cells, suggesting that ARL6IP5 may be a valuable novel chemotherapeutic against CisR OC.

Characterization of the nucleotide excision repair pathway and evaluation of compounds for overcoming the cisplatin resistance of non‑small cell lung cancer cell lines.

Lung cancer has been reported to be the leading cause of cancer‑related mortality worldwide. Cisplatin combination chemotherapy is a standard therapeutic strategy for patients with non‑small cell lung cancer (NSCLC) lacking driver mutations. However, the development of cisplatin resistance is a major obstacle to effective cancer treatment. The cellular mechanisms underlying cisplatin resistance have been previously revealed to be multifunctional. Accordingly, mechanistic analysis and the development of novel therapeutic strategies for cisplatin‑resistant NSCLC are urgently required. The present study mainly focused on the DNA repair mechanisms in cisplatin‑resistant NSCLC cells. Additionally, the effects of an Ecteinascidin (Et) derivative on cisplatin‑resistant cell lines were examined, by using a cisplatin‑resistant NSCLC cell line subjected to nucleotide excision repair (NER) pathway alterations. The results revealed that xeroderma pigmentosum group F‑complementing protein (XPF) mRNA expression was strongly associated with cisplatin resistance in cisplatin‑resistant NSCLC cell lines. XPF silencing significantly restored the sensitivity of cisplatin‑resistant PC‑14/CDDP cells to the drug. A potent anticancer effect of Et was observed in the cisplatin‑resistant cell line (PC‑14/CDDP), in which the NER pathway was altered. On the whole, these findings revealed that the expression levels of NER pathway‑related genes, including XPF, may have potential as biomarkers of cisplatin resistance. It was also suggested that Et may be a very promising compound for the development of novel anticancer drugs for the treatment of cisplatin‑resistant lung cancer.

Mechanisms of Cisplatin Resistance in HPV Negative Head and Neck Squamous Cell Carcinomas.

Head and neck squamous cell carcinomas (HNSCCs) are the eighth most common cancers worldwide. While promising new therapies are emerging, cisplatin-based chemotherapy remains the gold standard for advanced HNSCCs, although most of the patients relapse due to the development of resistance. This review aims to condense the different mechanisms involved in the development of cisplatin resistance in HNSCCs and highlight future perspectives intended to overcome its related complications. Classical resistance mechanisms include drug import and export, DNA repair and oxidative stress control. Emerging research identified the prevalence of these mechanisms in populations of cancer stem cells (CSC), which are the cells mainly contributing to cisplatin resistance. The use of old and new CSC markers has enabled the identification of the characteristics within HNSCC CSCs predisposing them to treatment resistance, such as cell quiescence, increased self-renewal capacity, low reactive oxygen species levels or the acquisition of epithelial to mesenchymal transcriptional programs. In the present review, we will discuss how cell intrinsic and extrinsic cues alter the phenotype of CSCs and how they influence resistance to cisplatin treatment. In addition, we will assess how the stromal composition and the tumor microenvironment affect drug resistance and the acquisition of CSCs’ characteristics through a complex interplay between extracellular matrix content as well as immune and non-immune cell characteristics. Finally, we will describe how alterations in epigenetic modifiers or other signaling pathways can alter tumor behavior and cell plasticity to induce chemotherapy resistance. The data generated in recent years open up a wide range of promising strategies to optimize cisplatin therapy, with the potential to personalize HNSCC patient treatment strategies.

MiR-133a targets YES1 to reduce cisplatin resistance in ovarian cancer by regulating cell autophagy

BackgroundAccumulating evidence has revealed that aberrant microRNA (miRNA) expression can affect the development of chemotherapy drug resistance by modulating the expression of relevant target proteins. Emerging evidence has demonstrated that miR-133a participates in the tumorigenesis of various cancers. However, whether miR-133a is associated with cisplatin resistance in ovarian cancer remains unclear.ObjectiveTo investigate the role of miR-133a in the development of cisplatin resistance in ovarian cancer.MethodsMiR-133a expression in cisplatin-resistant ovarian cancer cell lines was assessed by reverse-transcription quantitative PCR (RT–qPCR). A cell counting kit-8 (CCK-8) assay was used to evaluate the viability of tumour cells treated with cisplatin in the presence or absence of miR-133a. A luciferase reporter assay was used to analyse the binding of miR-133a with the 3′ untranslated region (3′UTR) of YES proto-oncogene 1 (YES1). The YES1 expression level was analysed using a dataset from the International Cancer Genome Consortium (ICGC) and assessed by RT–qPCR and western blotting in vitro. The roles and mechanisms of YES1 in cell functions were further probed via gain- and loss-of-function analysis.ResultsThe expression of miR-133a was significantly decreased in cisplatin-resistant ovarian cancer cell lines (A2780-DDP and SKOV3-DDP), and the overexpression of the miR-133a mimic reduced cisplatin resistance in A2780-DDP and SKOV3-DDP cells. Treatment with the miR-133a inhibitor increased cisplatin sensitivity in normal A2780 and SKOV3 cells. MiR-133a binds the 3’UTR of YES1 and downregulates its expression. Bioinformatics analysis revealed that YES1 expression was upregulated in recurrent cisplatin-resistant ovarian cancer tissue, and in vitro experiments also verified its upregulation in cisplatin-resistant cell lines. Furthermore, we discovered that miR-133a downregulated the expression of YES1 and thus inhibited cell autophagy to reduce cisplatin resistance. Yes1 knockdown significantly suppressed the cisplatin resistance of ovarian cancer cells by inhibiting autophagy in vitro. Xenograft tumour implantation further demonstrated that Yes1 overexpression promoted ovarian tumour development and cisplatin resistance.ConclusionsOur results suggest that the miR-133a/YES1 axis plays a critical role in cisplatin resistance in human ovarian cancer by regulating cell autophagy, which might serve as a promising therapeutic target for ovarian cancer chemotherapy treatment in the future.

CRISPR/Cas9-based genome-wide screening for deubiquitinase subfamily identifies USP1 regulating MAST1-driven cisplatin-resistance in cancer cells.

Background: Cisplatin is one of the frontline anticancer agents. However, development of cisplatin-resistance limits the therapeutic efficacy of cisplatin-based treatment. The expression of microtubule-associated serine/threonine kinase 1 (MAST1) is a primary factor driving cisplatin-resistance in cancers by rewiring the MEK pathway. However, the mechanisms responsible for MAST1 regulation in conferring drug resistance is unknown.Methods: We implemented a CRISPR/Cas9-based, genome-wide, dual screening system to identify deubiquitinating enzymes (DUBs) that govern cisplatin resistance and regulate MAST1 protein level. We analyzed K48- and K63-linked polyubiquitination of MAST1 protein and mapped the interacting domain between USP1 and MAST1 by immunoprecipitation assay. The deubiquitinating effect of USP1 on MAST1 protein was validated using rescue experiments, in vitro deubiquitination assay, immunoprecipitation assays, and half-life analysis. Furthermore, USP1-knockout A549 lung cancer cells were generated to validate the deubiquitinating activity of USP1 on MAST1 abundance. The USP1-MAST1 correlation was evaluated using bioinformatics tool and in different human clinical tissues. The potential role of USP1 in regulating MAST1-mediated cisplatin resistance was confirmed using a series of in vitro and in vivo experiments. Finally, the clinical relevance of the USP1-MAST1 axis was validated by application of small-molecule inhibitors in a lung cancer xenograft model in NSG mice.Results: The CRISPR/Cas9-based dual screening system identified USP1 as a novel deubiquitinase that interacts, stabilizes, and extends the half-life of MAST1 by preventing its K48-linked polyubiquitination. The expression analysis across human clinical tissues revealed a positive correlation between USP1 and MAST1. USP1 promotes MAST1-mediated MEK1 activation as an underlying mechanism that contributes to cisplatin-resistance in cancers. Loss of USP1 led to attenuation of MAST1-mediated cisplatin-resistance both in vitro and in vivo. The combined pharmacological inhibition of USP1 and MAST1 using small-molecule inhibitors further abrogated MAST1 level and synergistically enhanced cisplatin efficacy in a mouse xenograft model.Conclusions: Overall, our study highlights the role of USP1 in the development of cisplatin resistance and uncovers the regulatory mechanism of MAST1-mediated cisplatin resistance in cancers. Co-treatment with USP1 and MAST1 inhibitors abrogated tumor growth and synergistically enhanced cisplatin efficacy, suggesting a novel alternative combinatorial therapeutic strategy that could further improve MAST1-based therapy in patients with cisplatin-resistant tumors.

LncRNA NRON negatively regulates cisplatin-induced cell apoptosis via downregulating miR-31 in esophageal squamous cell carcinomas.

LncRNA non-coding repressor of NFAT (NRON) can promote bladder cancer and suppress liver cancer, while its role in esophageal squamous cell carcinoma (ESCC) is unknown. We analyzed its involvement in ESCC. NRON and miR-31 expression in plasma before and after cisplatin treatment was detected using RT-qPCR. The correlation between NRON and miR-31 was analyzed by linear regression. Expression of NRON and miR-31 in ESCC cells was also analyzed using RT-qPCR. Overexpression of NRON and miR-31 was achieved in ESCC cells to explore their interaction. Cell apoptosis induced by cisplatin was studied using cell apoptosis assay. NRON was highly expressed in ESCC and further upregulated after cisplatin treatment. MiR-31 was downregulated in ESCC and inversely correlated with NRON. In ESCC cells, NRON overexpression decreased miR-31 expression, while miR-31 failed to alter NRON expression. Cisplatin treatment promoted NRON expression and inhibited miR-31 expression. Under cisplatin treatment, cell apoptosis was inhibited after NRON overexpression and increased after miR-31 overexpression. Moreover, NRON inhibited the effect of miR-31 on cell apoptosis. NRON might promote the development of cisplatin resistance via downregulating miR-31 in ESCC.

Curcumin Synergizes with Cisplatin to Inhibit Colon Cancer through Targeting the MicroRNA-137-Glutaminase Axis.

Colorectal cancer (CRC) is one of the most lethal and prevalent malignancies world-wide. Currently, surgery, radiotherapy and chemotherapy are clinically applied as common approaches for CRC patients. Cisplatin is one of the most frequently used chemotherapy drugs for diverse cancers. Although chemotherapeutic strategies have improved the prognosis and survival of cancer patients, development of cisplatin resistance has led to cancer recurrence. Curcumin, isolated from turmeric, has been used as an effective anti-cancer agent. However, the molecular mechanisms for curcumin-mediated cisplatin sensitivity of CRC have not been elucidated. This study aimed to investigate the effects of curcumin treatment on cisplatin-resistant CRC cells. Expression levels of miRNAs and mRNAs were determined by qRT-PCR. Protein expression levels were detected by Western blotting. Cell responses to curcumin treatments were evaluated by MTT assay, Clonogenic assay and Annexin V apoptosis assay. The glutamine metabolism of colon cancer cells was assessed by glutamine uptake and glutaminase (GLS) activity. The binding of miR-137 on 3' UTR of GLS was validated by Western blotting and luciferase assay. Results demonstrated that curcumin significantly synergized with cisplatin (combination index <1) to suppress proliferation of colon cancer cells compared with curcumin or cisplatin alone. Moreover, from the established cisplatin-resistant cell line (HT-29), glutamine metabolism was remarkedly elevated in cisplatin-resistant CRC cells that displayed a glutamine addictive phenotype. Furthermore, curcumin treatments attenuated glutamine metabolism in colon cancer cells. Under low glutamine supply, colon cancer cells showed less sensitivity to curcumin. Using a microRNA (miRNA) microArray assay, miR-137, a tumor suppressor in colon cancer, was significantly induced by curcumin treatments in CRC cells. Bioinformatics analysis and a luciferase assay illustrated miR-137 directly targeted the 3' UTR of GLS mRNA. Rescue experiments demonstrated that miR-137-induced cisplatin sensitization was through targeting of GLS. Finally, curcumin treatment overcame cisplatin resistance through miR-137-mediated glutamine inhibition. Collectively, these results indicate that curcumin could be clinically applied as an anti-chemoresistance approach against CRC by modulating miR-137-inhibited glutamine metabolism.

Elevated N-Glycosylation Contributes to the Cisplatin Resistance of Non-Small Cell Lung Cancer Cells Revealed by Membrane Proteomic and Glycoproteomic Analysis.

Chemoresistance is the major restriction on the clinical use of cisplatin. Aberrant changes in protein glycosylation are closely associated with drug resistance. Comprehensive study on the role of protein glycosylation in the development of cisplatin resistance would contribute to precise elucidation of the complicated mechanism of resistance. However, comprehensive characterization of glycosylated proteins remains a big challenge. In this work, we integrated proteomic and N-glycoproteomic workflow to comprehensively characterize the cisplatin resistance-related membrane proteins. Using this method, we found that proteins implicated in cell adhesion, migration, response to drug, and signal transduction were significantly altered in both protein abundance and glycosylation level during the development of cisplatin resistance in the non-small cell lung cancer cell line. Accordingly, the ability of cell migration and invasion was markedly increased in cisplatin-resistant cells, hence intensifying their malignancy. In contrast, the intracellular cisplatin accumulation was significantly reduced in the resistant cells concomitant with the down-regulation of drug uptake channel protein, LRRC8A, and over-expression of drug efflux pump proteins, MRP1 and MRP4. Moreover, the global glycosylation was elevated in the cisplatin-resistant cells. Consequently, inhibition of N-glycosylation reduced cell resistance to cisplatin, whereas promoting the high-mannose or sialylated type of glycosylation enhanced the resistance, suggesting that critical glycosylation type contributes to cisplatin resistance. These results demonstrate the high efficiency of the integrated proteomic and N-glycoproteomic workflow in discovering drug resistance-related targets, and provide new insights into the mechanism of cisplatin resistance.

Role of HMGB1 in Cisplatin-Persistent Lung Adenocarcinoma Cell Lines

Significant advances have been made recently in the development of targeted therapy for lung adenocarcinoma. However, platinum-based chemotherapy remains as the cornerstone in the treatment of this neoplasm. This is the treatment option for adenocarcinomas without EGFR gain-of-function mutations or tumors that have developed resistance to targeted therapy. The High-Mobility Group Box 1 (HMGB1) is a multifunctional protein involved in intrinsic resistance to cisplatin. HMGB1 is released when cytotoxic agents, such as cisplatin, induce cell death. In the extracellular milieu, HMGB1 acts as adjuvant to induce an antitumor immune response. However, the opposite effect favoring tumor progression has also been reported. In this study, the effects of cisplatin in lung adenocarcinoma cell lines harboring clinically relevant mutations, such as EGFR mutations, were studied. Subcellular localization of HMGB1 was detected in the cell lines and in viable cells after a single exposure to cisplatin, which are designated as cisplatin-persistent cells. The mRNA expression of the receptor for advanced glycation end products (RAGE), TLR-2, and TLR-4 receptors was measured in parental cell lines and their persistent variants. Finally, changes in plasma HMGB1 from a cohort of lung adenocarcinoma patients without EGFR mutation and treated with cisplatin-based therapy were analyzed. Cisplatin-susceptible lung adenocarcinoma cell lines died by apoptosis or necrosis and released HMGB1. In cisplatin-persistent cells, nuclear relocalization of HMGB1 and overexpression of HMGB1 and RAGE, but not TLR-2 or TLR-4, were observed. In tumor cells, this HMGB1–RAGE interaction may be associated with the development of cisplatin resistance. The results indicate a direct relationship between the plasma levels of HMGB1 and overall survival. In conclusion, HMGB1 may be an effective biomarker associated with increased overall survival of lung adenocarcinoma patients.