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2.
Support Care Cancer ; 31(7): 420, 2023 Jun 24.
Article in English | MEDLINE | ID: mdl-37354234

ABSTRACT

In India, approximately 1.4 million new cases of cancer are recorded annually, with 26.7 million people living with cancer in 2021. Providing care for family members with cancer impacts caregivers' health and financial resources. Effects on caregivers' health and financial resources, understood as family and caregiver "financial toxicity" of cancer, are important to explore in the Indian context, where family members often serve as caregivers, in light of cultural attitudes towards family. This is reinforced by other structural issues such as grave disparities in socioeconomic status, barriers in access to care, and limited access to supportive care services for many patients. Effects on family caregivers' financial resources are particularly prevalent in India given the increased dependency on out-of-pocket financing for healthcare, disparate access to insurance coverage, and limitations in public expenditure on healthcare. In this paper, we explore family and caregiver financial toxicity of cancer in the Indian context, highlighting the multiple psychosocial aspects through which these factors may play out. We suggest steps forward, including future directions in (1) health services research, (2) community-level interventions, and (3) policy changes. We underscore that multidisciplinary and multi-sectoral efforts are needed to study and address family and caregiver financial toxicity in India.


Subject(s)
Caregivers , Neoplasms , Humans , Caregivers/psychology , Family , Social Class , Neoplasms/therapy , India
3.
Nat Commun ; 13(1): 6623, 2022 11 04.
Article in English | MEDLINE | ID: mdl-36333297

ABSTRACT

Activities of dendritic cells (DCs) that present tumor antigens are often suppressed in tumors. Here we report that this suppression is induced by tumor microenvironment-derived factors, which activate the activating transcription factor-3 (ATF3) transcription factor and downregulate cholesterol 25-hydroxylase (CH25H). Loss of CH25H in antigen presenting cells isolated from human lung tumors is associated with tumor growth and lung cancer progression. Accordingly, mice lacking CH25H in DCs exhibit an accelerated tumor growth, decreased infiltration and impaired activation of intratumoral CD8+ T cells. These mice do not establish measurable long-term immunity against malignant cells that undergo chemotherapy-induced immunogenic cell death. Mechanistically, downregulation of CH25H stimulates membrane fusion between endo-phagosomes and lysosomes, accelerates lysosomal degradation and restricts cross-presentation of tumor antigens in the intratumoral DCs. Administration of STING agonist MSA-2 reduces the lysosomal activity in DCs, restores antigen cross presentation, and increases therapeutic efficacy of PD-1 blockade against tumour challenge in a CH25H-dependent manner. These studies highlight the importance of downregulation of CH25H in DCs for tumor immune evasion and resistance to therapy.


Subject(s)
Cross-Priming , Lung Neoplasms , Mice , Humans , Animals , Antigens, Neoplasm , CD8-Positive T-Lymphocytes , Dendritic Cells , Lung Neoplasms/metabolism , Lysosomes , Mice, Inbred C57BL , Tumor Microenvironment
4.
Cancer Immunol Res ; 10(12): 1490-1505, 2022 12 02.
Article in English | MEDLINE | ID: mdl-36255418

ABSTRACT

Fragility of regulatory T (Treg) cells manifested by the loss of neuropilin-1 (NRP1) and expression of IFNγ undermines the immune suppressive functions of Treg cells and contributes to the success of immune therapies against cancers. Intratumoral Treg cells somehow avoid fragility; however, the mechanisms by which Treg cells are protected from fragility in the tumor microenvironment are not well understood. Here, we demonstrate that the IFNAR1 chain of the type I IFN (IFN1) receptor was downregulated on intratumoral Treg cells. Downregulation of IFNAR1 mediated by p38α kinase protected Treg cells from fragility and maintained NRP1 levels, which were decreased in response to IFN1. Genetic or pharmacologic inactivation of p38α and stabilization of IFNAR1 in Treg cells induced fragility and inhibited their immune suppressive and protumorigenic activities. The inhibitor of sumoylation TAK981 (Subasumstat) upregulated IFNAR1, eliciting Treg fragility and inhibiting tumor growth in an IFNAR1-dependent manner. These findings describe a mechanism by which intratumoral Treg cells retain immunosuppressive activities and suggest therapeutic approaches for inducing Treg fragility and increasing the efficacy of immunotherapies.


Subject(s)
Neoplasms , T-Lymphocytes, Regulatory , Humans , Tumor Microenvironment , Neuropilin-1 , Immunotherapy
5.
Cell Metab ; 34(9): 1342-1358.e7, 2022 09 06.
Article in English | MEDLINE | ID: mdl-36070682

ABSTRACT

Effector trogocytosis between malignant cells and tumor-specific cytotoxic T lymphocytes (CTLs) contributes to immune evasion through antigen loss on target cells and fratricide of antigen-experienced CTLs by other CTLs. The mechanisms regulating these events in tumors remain poorly understood. Here, we demonstrate that tumor-derived factors (TDFs) stimulated effector trogocytosis and restricted CTLs' tumoricidal activity and viability in vitro. TDFs robustly altered the CTL's lipid profile, including depletion of 25-hydroxycholesterol (25HC). 25HC inhibited trogocytosis and prevented CTL's inactivation and fratricide. Mechanistically, TDFs induced ATF3 transcription factor that suppressed the expression of 25HC-regulating gene-cholesterol 25-hydroxylase (CH25H). Stimulation of trogocytosis in the intratumoral CTL by the ATF3-CH25H axis attenuated anti-tumor immunity, stimulated tumor growth, and impeded the efficacy of chimeric antigen receptor (CAR) T cell adoptive therapy. Through use of armored CAR constructs or pharmacologic agents restoring CH25H expression, we reversed these phenotypes and increased the efficacy of immunotherapies.


Subject(s)
T-Lymphocytes, Cytotoxic , Trogocytosis , Immunotherapy , Steroid Hydroxylases , Virus Replication/genetics
6.
Biomed Res Int ; 2022: 6392206, 2022.
Article in English | MEDLINE | ID: mdl-35993044

ABSTRACT

Breast cancer is the most prevalent form of cancer that can strike at any age; the higher the age, the greater the risk. The presence of malignant tissue has become more frequent in women. Although medical therapy has improved breast cancer diagnostic and treatment methods, still the death rate remains high due to failure of diagnosing breast cancer in its early stages. A classification approach for mammography images based on nonsubsampled contourlet transform (NSCT) is proposed in order to investigate it. The proposed method uses multiresolution NSCT decomposition to the region of interest (ROI) of mammography images and then uses Z-moments for extracting features from the NSCT-decomposed images. The matrix is formed by the components that are extracted from the region of interest and are then subjected to singular value decomposition (SVD) in order to remove the essential features that can generalize globally. The method employs a support vector machine (SVM) classification algorithm to categorize mammography pictures into normal, benign, and malignant and to identify and classify the breast lesions. The accuracy of the proposed model is 96.76 percent, and the training time is greatly decreased, as evident from the experiments performed. The paper also focuses on conducting the feature extraction experiments using morphological spectroscopy. The experiment combines 16 different algorithms with 4 classification methods for achieving exceptional accuracy and time efficiency outcomes as compared to other existing state-of-the-art approaches.


Subject(s)
Breast Neoplasms , Algorithms , Breast , Breast Neoplasms/diagnostic imaging , Female , Humans , Mammography/methods , Support Vector Machine
7.
Nat Cancer ; 3(7): 808-820, 2022 07.
Article in English | MEDLINE | ID: mdl-35637402

ABSTRACT

Evasion of antitumor immunity and resistance to therapies in solid tumors are aided by an immunosuppressive tumor microenvironment (TME). We found that TME factors, such as regulatory T cells and adenosine, downregulated type I interferon receptor IFNAR1 on CD8+ cytotoxic T lymphocytes (CTLs). These events relied upon poly-ADP ribose polymerase-11 (PARP11), which was induced in intratumoral CTLs and acted as a key regulator of the immunosuppressive TME. Ablation of PARP11 prevented loss of IFNAR1, increased CTL tumoricidal activity and inhibited tumor growth in an IFNAR1-dependent manner. Accordingly, genetic or pharmacologic inactivation of PARP11 augmented the therapeutic benefits of chimeric antigen receptor T cells. Chimeric antigen receptor CTLs engineered to inactivate PARP11 demonstrated a superior efficacy against solid tumors. These findings highlight the role of PARP11 in the immunosuppressive TME and provide a proof of principle for targeting this pathway to optimize immune therapies.


Subject(s)
Neoplasms , Poly(ADP-ribose) Polymerases/metabolism , Receptors, Chimeric Antigen , Humans , Immunosuppression Therapy , Immunotherapy, Adoptive , Neoplasms/drug therapy , Receptors, Chimeric Antigen/genetics , Tumor Microenvironment
8.
Nat Med ; 28(4): 649-657, 2022 04.
Article in English | MEDLINE | ID: mdl-35440716

ABSTRACT

Cancer research currently is heavily skewed toward high-income countries (HICs), with little research conducted in, and relevant to, the problems of low- and middle-income countries (LMICs). This regional discordance in cancer knowledge generation and application needs to be rebalanced. Several gaps in the research enterprise of LMICs need to be addressed to promote regionally relevant research, and radical rethinking is needed to address the burning issues in cancer care in these regions. We identified five top priorities in cancer research in LMICs based on current and projected needs: reducing the burden of patients with advanced disease; improving access and affordability, and outcomes of cancer treatment; value-based care and health economics; quality improvement and implementation research; and leveraging technology to improve cancer control. LMICs have an excellent opportunity to address important questions in cancer research that could impact cancer control globally. Success will require collaboration and commitment from governments, policy makers, funding agencies, health care organizations and leaders, researchers and the public.


Subject(s)
Developing Countries , Neoplasms , Delivery of Health Care , Humans , Income , Neoplasms/epidemiology , Neoplasms/therapy , Poverty , Research
9.
Cell Biol Toxicol ; 36(3): 273-278, 2020 06.
Article in English | MEDLINE | ID: mdl-31758290

ABSTRACT

Glioblastoma (GBM) is the most aggressive type of glioma. Temozolomide (TMZ) is currently the drug of choice used for post-operative chemotherapy of GBM. However, the presence of intrinsic and acquired resistance hinders the success of chemotherapy. To understand the TMZ resistant mechanisms in glioma, we investigated the alterations in cellular signaling pathways by performing transcriptome analysis of TMZ treated glioma cells. Gene Set Enrichment Analysis (GSEA) indicated a significant enrichment of Wnt/ß-catenin signaling besides many other pathways in TMZ treated cells. Further, we demonstrate that TMZ treatment increased the activity from TOPflash reporter, (a Wnt responsive reporter), enhanced the levels of pGSK-3ß (S9) and reduced the levels of p-ß-catenin (S33/37/T41) with a concomitant increase in transcript and protein levels of Wnt targets in a concentration and time-dependent manner. While TMZ treated cells did not show alteration in any of the Wnt ligands, PI3K inhibitor (LY294002) treatment repressed Akt activation and abolished the TMZ-mediated induction of Wnt/ß-catenin pathway. In addition, we show that Wnt/ß-catenin signaling activation by TMZ is independent of ATM/Chk2 pathway. Further, we also demonstrate the activation of mTOR pathway after TMZ treatment. Thus, our results demonstrate that activation of Wnt/ß-catenin pathway involves an ATM/Chk2- independent PI3K/Akt/GSK-3 cascade in TMZ treated cells and further provides mechanistic basis for the chemoresistance of glioma to TMZ.


Subject(s)
Glioma/metabolism , Temozolomide/pharmacology , Wnt Signaling Pathway/physiology , Brain Neoplasms/drug therapy , Cell Line, Tumor , Drug Resistance, Neoplasm/drug effects , Gene Expression Regulation, Neoplastic/drug effects , Glioblastoma/metabolism , Glioma/drug therapy , Glycogen Synthase Kinase 3/metabolism , Humans , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Temozolomide/metabolism , Wnt Proteins/metabolism , Xenograft Model Antitumor Assays , beta Catenin/metabolism
10.
J Biol Chem ; 294(38): 14081-14095, 2019 09 20.
Article in English | MEDLINE | ID: mdl-31366730

ABSTRACT

TP53 is the most frequently mutated tumor suppressor gene in many cancers, yet biochemical characterization of several of its reported mutations with probable biological significance have not been accomplished enough. Specifically, missense mutations in TP53 can contribute to tumorigenesis through gain-of-function of biochemical and biological properties that stimulate tumor growth. Here, we identified a relatively rare mutation leading to a proline to leucine substitution (P152L) in TP53 at the very end of its DNA-binding domain (DBD) in a sample from an Indian oral cancer patient. Although the P152Lp53 DBD alone bound to DNA, the full-length protein completely lacked binding ability at its cognate DNA motifs. Interestingly, P152Lp53 could efficiently tetramerize, and the mutation had only a limited impact on the structure and stability of full-length p53. Significantly, when we expressed this variant in a TP53-null cell line, it induced cell motility, proliferation, and invasion compared with a vector-only control. Also, enhanced tumorigenic potential was observed when P152Lp53-expressing cells were xenografted into nude mice. Investigating the effects of P152Lp53 expression on cellular pathways, we found that it is associated with up-regulation of several pathways, including cell-cell and cell-extracellular matrix signaling, epidermal growth factor receptor signaling, and Rho-GTPase signaling, commonly active in tumorigenesis and metastasis. Taken together, our findings provide a detailed account of the biochemical and cellular alterations associated with the cancer-associated P152Lp53 variant and establish it as a gain-of-function TP53 variant.


Subject(s)
Carcinogenesis/genetics , Tumor Suppressor Protein p53/genetics , Animals , Cell Line, Tumor , Cell Movement/genetics , Cell Proliferation/genetics , Female , Gain of Function Mutation , Humans , Lung Neoplasms/genetics , Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Mice , Mice, Nude , Mouth Neoplasms/genetics , Mouth Neoplasms/metabolism , Mouth Neoplasms/pathology , Neoplasm Invasiveness/genetics , Polymorphism, Single Nucleotide , Signal Transduction/genetics , Transcriptional Activation , Tumor Suppressor Protein p53/metabolism , Xenograft Model Antitumor Assays
11.
Biochem Biophys Res Commun ; 515(1): 241-247, 2019 07 12.
Article in English | MEDLINE | ID: mdl-31146910

ABSTRACT

Phosphatases play an important role in cellular signaling and are often found dysregulated in cancers including glioblastoma (GBM). A comprehensive bioinformatics analysis of phosphatases (n = 403) in multiple datasets revealed their deregulation in GBM. Among the differentially regulated phosphatases (n = 186; 46.1%), majority of them were found to be regulated by microRNA (n = 94; 50.5%) followed by DNA methylation (n = 22; 11.8%) and altered copy number variation (n = 10; 5.37%). STYXL1 (Serine/threonine/tyrosine-interacting-like protein 1) was found to be the second most amplified gene in GBM, upregulated, and correlated to poor prognosis. The expression of STYXL1 was also found to be higher in IDH1 mutant gliomas and G-CIMP- gliomas which are reported to be more aggressive than their corresponding counterparts. Silencing STYXL1 inhibited glioma cell growth, soft agar colony formation, migration, invasion, proliferation, and xenograft tumor growth. Further, ectopic expression of STYXL1 was found to promote glioma cell growth, soft agar colony formation, migration, and RasV12 induced in-vitro transformation of immortalized human astrocytes, thus confirming its oncogenic potential in GBM. In this report, we provide a comprehensive overview of deregulation of phosphatases in GBM and demonstrate for the first time, the oncogenic nature of STYXL1 in GBM. This study might be useful for treatment of GBM patients with deregulated STYXL1.


Subject(s)
Apoptosis Regulatory Proteins/genetics , Brain Neoplasms/genetics , Carcinogenesis/genetics , Glioma/genetics , Phosphoric Monoester Hydrolases/genetics , Animals , Apoptosis Regulatory Proteins/metabolism , Brain Neoplasms/metabolism , Brain Neoplasms/therapy , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Glioma/metabolism , Glioma/therapy , Humans , Mice , Phosphoric Monoester Hydrolases/metabolism , RNAi Therapeutics/methods , Xenograft Model Antitumor Assays/methods
12.
Mol Cell Biol ; 39(6)2019 03 15.
Article in English | MEDLINE | ID: mdl-30617160

ABSTRACT

MicroRNA 155 (miR-155) is an oncomir, generated as a noncoding RNA from the BIC gene whose promoter activity is mainly controlled via activation protein 1 (AP-1) and NF-κB transcription factors. We found that the expression levels of miR-155 and programmed cell death 4 (Pdcd4) exhibit inverse relationships in tongue cancer cells (SAS and AWL) and tumor tissues compared to their relationships in normal FBM cells and normal tongue tissues, respectively. In silico and in vitro studies with the 3' untranslated region (UTR) of Pdcd4 via luciferase reporter assays, quantitative PCR (qPCR), and Western blotting showed that miR-155 directly targets Pdcd4 mRNA and blocks its expression. Ectopic expression of Pdcd4 or knockdown of miR-155 in tongue cancer cells predominantly reduces AP-1-dependent transcriptional activity of the BIC promoter and decreases miR-155 expression. In this study, we demonstrate that miR-155 expression is modulated by a feedback loop between Pdcd4, AP-1, and miR-155 which results in enhanced expression of miR-155 with a consequent progression of tongue tumorigenesis. Further, miR-155 knockdown increases apoptosis, arrests the cell cycle, regresses tumor size in xenograft nude mice, and reduces cell viability and colony formation in soft-agar and clonogenic assays. Thus, the restoration of Pdcd4 levels by the use of molecular manipulation such as using a miR-155 sponge has an essential role in the therapeutic intervention of cancers, including tongue cancer.


Subject(s)
Apoptosis Regulatory Proteins/metabolism , MicroRNAs/genetics , RNA-Binding Proteins/metabolism , Tongue Neoplasms/genetics , Transcription Factor AP-1/metabolism , 3' Untranslated Regions , Animals , Apoptosis/physiology , Apoptosis Regulatory Proteins/genetics , Carcinogenesis , Cell Line, Tumor , Cell Movement/physiology , Cell Proliferation/physiology , Cell Survival/physiology , Cell Transformation, Neoplastic , Feedback, Physiological , Female , HEK293 Cells , Humans , Mice , Mice, Inbred BALB C , Mice, Nude , MicroRNAs/biosynthesis , MicroRNAs/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , RNA-Binding Proteins/genetics , Tongue Neoplasms/metabolism , Tongue Neoplasms/pathology , Xenograft Model Antitumor Assays
13.
Phys Rev Lett ; 100(3): 036106, 2008 Jan 25.
Article in English | MEDLINE | ID: mdl-18233009

ABSTRACT

We examine the surface morphological evolution of a conducting crystalline solid under the simultaneous action of an electric field and mechanical stress based on a fully nonlinear model and combining linear stability theory with self-consistent dynamical simulations. We demonstrate that electric current, through surface electromigration, can stabilize the surface morphology of the stressed solid against cracklike surface instabilities. The results also have more general implications for the morphological response of solid surfaces under the simultaneous action of multiple external forces.

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