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1.
Oncogene ; 41(45): 4929-4940, 2022 11.
Article in English | MEDLINE | ID: mdl-36182968

ABSTRACT

Cisplatin, 5FU and docetaxel (TPF) are the most common chemotherapy regimen used for advanced OSCC. However, many cancer patients experience relapse, continued tumor growth, and spread due to drug resistance, which leads to treatment failure and metastatic disease. Here, using a CRISPR/Cas9 based kinome knockout screening, Misshapen-like kinase 1 (MINK1) is identified as an important mediator of 5FU resistance in OSCC. Analysis of clinical samples demonstrated significantly higher MINK1 expression in the tumor tissues of chemotherapy non-responders as compared to chemotherapy responders. The nude mice and zebrafish xenograft experiments indicate that knocking out MINK1 restores 5FU mediated cell death in chemoresistant OSCC. An antibody based phosphorylation array screen revealed MINK1 as a negative regulator of p53. Mechanistically, MINK1 modulates AKT phosphorylation at Ser473, which enables p-MDM2 (Ser 166) mediated degradation of p53. We also identified lestaurtinib as a potent inhibitor of MINK1 kinase activity. The patient derived TPF resistant cell based xenograft data suggest that lestaurtinib restores 5FU sensitivity and facilitates a significant reduction of tumor burden. Overall, our study suggests that MINK1 is a major driver of 5FU resistance in OSCC. The novel combination of MINK1 inhibitor lestaurtinib and 5FU needs further clinical investigation in advanced OSCC.


Subject(s)
Proto-Oncogene Proteins c-akt , Tumor Suppressor Protein p53 , Mice , Animals , Humans , Proto-Oncogene Proteins c-akt/metabolism , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Protein p53/metabolism , Mice, Nude , Zebrafish/metabolism , Neoplasm Recurrence, Local/drug therapy , Cisplatin/pharmacology , Fluorouracil/therapeutic use , Cell Line, Tumor , Drug Resistance, Neoplasm/genetics , Proto-Oncogene Proteins c-mdm2/genetics , Proto-Oncogene Proteins c-mdm2/metabolism , Protein Serine-Threonine Kinases/genetics
2.
FASEB J ; 36(10): e22566, 2022 10.
Article in English | MEDLINE | ID: mdl-36165231

ABSTRACT

CMTM6, a type 3 transmembrane protein, is known to stabilize the expression of programmed cell death ligand 1 (PD-L1) and hence facilitates the immune evasion of tumor cells. Recently, we demonstrated that CMTM6 is a major driver of cisplatin resistance in oral squamous cell carcinomas (OSCC). However, the detailed mechanism of how CMTM6 rewires cisplatin resistance in OSCC is yet to be explored. RNA sequencing analysis of cisplatin-resistant OSCC lines stably expressing Nt shRNA and CMTM6 shRNA revealed that CMTM6 might be a potential regulator of the ribosome biogenesis network. Knocking down CMTM6 significantly inhibited transcription of 47S precursor rRNA and hindered the nucleolar structure, indicating reduced ribosome biogenesis. When CMTM6 was ectopically over-expressed in CMTM6KD cells, almost all ribosomal machinery components were rescued. Mechanistically, CMTM6 induced the expression of C-Myc, which promotes RNA polymerase I mediated rDNA transcription. In addition to this, CMTM6 was also found to regulate the AKT-mTORC1-dependent ribosome biogenesis and protein synthesis in cisplatin-resistant lines. The nude mice and zebrafish xenograft experiments indicate that blocking ribosome synthesis either by genetic inhibitor (CMTM6KD) or pharmacological inhibitor (CX-5461) significantly restores cisplatin-mediated cell death in chemoresistant OSCC. Overall, our study suggests that CMTM6 is a major regulator of the ribosome biogenesis network and targeting the ribosome biogenesis network is a viable target to overcome chemoresistance in OSCC. The novel combination of CX-5461 and cisplatin deserves further clinical investigation in advanced OSCC.


Subject(s)
Carcinoma, Squamous Cell , Head and Neck Neoplasms , Mouth Neoplasms , Animals , B7-H1 Antigen , Carcinoma, Squamous Cell/genetics , Cell Death , Cell Line, Tumor , Cisplatin/pharmacology , DNA, Ribosomal , Humans , Ligands , Mechanistic Target of Rapamycin Complex 1 , Mice , Mice, Nude , Mouth Neoplasms/drug therapy , Mouth Neoplasms/pathology , Proto-Oncogene Proteins c-akt , RNA Polymerase I , RNA, Small Interfering , Ribosomes , Squamous Cell Carcinoma of Head and Neck , Zebrafish/genetics
3.
Int J Environ Health Res ; 32(8): 1716-1732, 2022 Aug.
Article in English | MEDLINE | ID: mdl-33769141

ABSTRACT

This study investigated the influence of climate factors on malaria incidence in the Sundargarh district, Odisha, India. The WEKA machine learning tool was used with two classifier techniques, Multi-Layer Perceptron (MLP) and J48, with three test options, 10-fold cross-validation, percentile split, and supplied test. A comparative analysis was carried out to ascertain the superior model among malaria prediction accuracy techniques in varying climate contexts. The results suggested that J48 had exhibited better skill than MLP with the 10-fold cross-validation method over the percentile split and supplied test options. J48 demonstrated less error (RMSE = 0.6), better kappa = 0.63, and higher accuracy = 0.71), suggesting it as most suitable model. Seasonal variation of temperature and humidity had a better association with malaria incidents than rainfall, and the performance was better during the monsoon and post-monsoon when the incidents are at the peak.


Subject(s)
Machine Learning , Malaria , Climate , Humans , Malaria/epidemiology , Neural Networks, Computer , Seasons
5.
Br J Cancer ; 124(12): 2004-2016, 2021 06.
Article in English | MEDLINE | ID: mdl-33762722

ABSTRACT

BACKGROUND: Chemoresistance is one of the major factors for treatment failure in OSCC. Identifying key resistance triggering molecules will be useful strategy for developing novel treatment methods. METHODS: To identify the causative factors of chemoresistance, we performed RNA sequencing and global proteomic profiling of human OSCC lines presenting with sensitive, early and late cisplatin-resistance patterns. RESULTS: From the common set of dysregulated genes from both the analysis, RRBP1 was identified to be upregulated in both early and late cisplatin-resistant cells with respect to the sensitive counterpart. Analysis of OSCC patient sample indicates that RRBP1 expression is upregulated in chemotherapy-non-responder tumours as compared to chemotherapy-responder tumours. Genetic (knockout) or pharmacological (Radezolid, represses expression of RRBP1) inhibition of RRBP1 restores cisplatin-mediated cell death in chemo-resistant OSCC. Mechanistically, RRBP1 regulates Yes-associated protein1 (YAP1), a key protein in the Hippo pathway to induce chemoresistance. The PDC xenograft data suggests that knockout of RRBP1 induces cisplatin-mediated cell death and facilitates a significant reduction of tumour burden. CONCLUSION: Overall, our data suggests that (I) RRBP1 is a major driver of cisplatin-resistance in OSCC, (II) RRBP1 regulates YAP1 expression to mediate cisplatin-resistance, (III) Radezolid represses RRBP1 expression and (IV) targeting RRBP1 reverses cisplatin-induced chemoresistance in advanced OSCC.


Subject(s)
Carcinoma, Squamous Cell/drug therapy , Carrier Proteins/physiology , Cisplatin/therapeutic use , Drug Resistance, Neoplasm/genetics , Mouth Neoplasms/drug therapy , Animals , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Carrier Proteins/genetics , Cell Line, Tumor , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/genetics , Gene Knockout Techniques , HEK293 Cells , Hippo Signaling Pathway/drug effects , Hippo Signaling Pathway/genetics , Humans , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Mouth Neoplasms/genetics , Mouth Neoplasms/pathology , Xenograft Model Antitumor Assays
6.
JCI Insight ; 6(4)2021 02 22.
Article in English | MEDLINE | ID: mdl-33434185

ABSTRACT

Rewiring tumor cells to undergo drug-induced apoptosis is a promising way to overcome chemoresistance. Therefore, identifying causative factors for chemoresistance is of high importance. Unbiased global proteome profiling of sensitive, early, and late cisplatin-resistant oral squamous cell carcinoma (OSCC) lines identified CMTM6 as a top-ranked upregulated protein. Analyses of OSCC patient tumor samples demonstrated significantly higher CMTM6 expression in chemotherapy (CT) nonresponders as compared with CT responders. In addition, a significant association between higher CMTM6 expression and poorer relapse-free survival in esophageal squamous cell carcinoma, head and neck squamous cell carcinoma, and lung squamous cell carcinoma was observed from Kaplan-Meier plot analysis. Stable knockdown (KD) of CMTM6 restored cisplatin-mediated cell death in chemoresistant OSCC lines. Upon CMTM6 overexpression in CMTM6-KD lines, the cisplatin-resistant phenotype was rescued. The patient-derived cell xenograft model of chemoresistant OSCC displaying CMTM6 depletion restored the cisplatin-induced cell death and tumor burden substantially. The transcriptome analysis of CMTM6-KD and control chemoresistant cells depicted enrichment of the Wnt signaling pathway. We demonstrated that CMTM6 interaction with membrane-bound Enolase-1 stabilized its expression, leading to activation of Wnt signaling mediated by AKT-glycogen synthase kinase-3ß. CMTM6 has been identified as a stabilizer of programmed cell death ligand 1. Therefore, as CMTM6 facilitates tumor cells for immune evasion and mediates cisplatin resistance, it could be a promising therapeutic target for treating therapy-resistant OSCC.


Subject(s)
Cisplatin/pharmacology , DNA-Binding Proteins/metabolism , Drug Resistance, Neoplasm/drug effects , Glycogen Synthase Kinase 3 beta/metabolism , Myelin Proteins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Wnt Signaling Pathway/drug effects , Animals , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Biomarkers, Tumor/metabolism , Carcinoma, Squamous Cell/pathology , Cell Death , Cell Line, Tumor , Esophageal Neoplasms/genetics , Esophageal Squamous Cell Carcinoma/drug therapy , Esophageal Squamous Cell Carcinoma/genetics , Gene Expression Regulation, Neoplastic/drug effects , Glycogen Synthase Kinase 3 beta/genetics , Head and Neck Neoplasms/drug therapy , Head and Neck Neoplasms/genetics , Humans , MARVEL Domain-Containing Proteins , Male , Mice , Mice, Inbred BALB C , Mice, Nude , Mouth Neoplasms/drug therapy , Mouth Neoplasms/pathology , Myelin Proteins/genetics , Phosphopyruvate Hydratase/metabolism , Squamous Cell Carcinoma of Head and Neck/drug therapy , Squamous Cell Carcinoma of Head and Neck/genetics , Tumor Suppressor Proteins/metabolism , Up-Regulation/drug effects
7.
Front Oncol ; 10: 612337, 2020.
Article in English | MEDLINE | ID: mdl-33718113

ABSTRACT

m6A RNA methylation, which serves as a critical regulator of transcript expression, has gathered tremendous scientific interest in recent years. From RNA processing to nuclear export, RNA translation to decay, m6A modification has been studied to affect various aspects of RNA metabolism, and it is now considered as one of the most abundant epitranscriptomic modification. RNA methyltransferases (writer), m6A-binding proteins (readers), and demethylases (erasers) proteins are frequently upregulated in several neoplasms, thereby regulating oncoprotein expression, augmenting tumor initiation, enhancing cancer cell proliferation, progression, and metastasis. Though the potential role of m6A methylation in growth and proliferation of cancer cells has been well documented, its potential role in development of therapy resistance in cancer is not clear. In this review, we focus on m6A-associated regulation, mechanisms, and functions in acquired chemoresistance, radioresistance, and resistance to immunotherapy in cancer.

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