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1.
J Pediatr Hematol Oncol ; 43(1): e119-e122, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-31913943

RESUMO

Synovial sarcoma is a mesenchymal neoplasm that shows a specific t(X;18) translocation that leads to the formation of SS18-SSX gene fusions and is most commonly seen in soft tissues of the extremity. The gastrointestinal tract is a very rare site of involvement. We report a case of primary gastric synovial sarcoma in a 13-year-old male child. Synovial sarcoma should be included in the differential diagnosis when spindle cell neoplasms are encountered in the stomach. A high degree of suspicion, followed by the necessary immunohistochemistry and molecular studies, is required to make an accurate diagnosis.


Assuntos
Proteínas de Fusão Oncogênica/genética , Sarcoma Sinovial/diagnóstico , Neoplasias Gástricas/diagnóstico , Translocação Genética , Adolescente , Humanos , Masculino , Prognóstico , Sarcoma Sinovial/genética , Neoplasias Gástricas/genética
2.
Lasers Surg Med ; 53(10): 1435-1445, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34058028

RESUMO

BACKGROUND AND OBJECTIVES: Despite having numerous advances in therapeutics, mortality and morbidity due to oral cancer incidence are still very high. Early detection can improve the chances of survival in most patients. However, diagnosis at early stages can be challenging as premalignant conditions are usually asymptomatic. Currently, histological assessment remains the gold standard for diagnosis. Early diagnosis poses challenges to pathologists due to less severe morphological changes associated with early stages. Therefore, a fast and robust method of detection based on molecular changes is needed for early diagnosis. © 2021 Wiley Periodicals LLC. STUDY DESIGN/MATERIAL AND METHODS: In the present study, Fourier transform infrared (FTIR) spectroscopic imaging has been used to differentiate early-stage oral hyperplasia from adjacent normal (AN) and oral squamous cell carcinoma (OSCC). Hyperplasia is often considered as an initial event in the pathogenesis of oral cancer and OSCC is the most common advanced stage of malignancy. Differentiating normal versus hyperplasia and hyperplasia versus OSCC can remain quite challenging on occasion using conventional staining as the histological assessment is based on morphological changes. RESULTS: Unsupervised hierarchical cluster analysis (UHCA) has been performed on FTIR images of multiple tissues together that provided some degree of classification among tissue groups. The AN epithelium clustered distinctively using UHCA from both hyperplasia and grades 1 and 2 of OSCC. An increase in the content of DNA, denaturation of protein, and altered lipid structures were more clearly elucidated with spectral analysis. CONCLUSION: This study demonstrates a simple strategy to differentiate early-stage oral hyperplasia from AN and OSCC using UHCA. This study also proposes a future alternative method where FTIR imaging can be used as a diagnostic tool for cancer at early stages.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Carcinoma de Células Escamosas/diagnóstico por imagem , Detecção Precoce de Câncer , Humanos , Hiperplasia , Neoplasias Bucais/diagnóstico por imagem , Análise Multivariada
3.
Gastric Cancer ; 23(5): 796-810, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32333232

RESUMO

BACKGROUND: Phosphorylation is an important regulatory mechanism of protein activity in cells. Studies in various cancers have reported perturbations in kinases resulting in aberrant phosphorylation of oncoproteins and tumor suppressor proteins. METHODS: In this study, we carried out quantitative phosphoproteomic analysis of gastric cancer tissues and corresponding xenograft samples. Using these data, we employed bioinformatics analysis to identify aberrant signaling pathways. We further performed molecular inhibition and silencing of the upstream regulatory kinase in gastric cancer cell lines and validated its effect on cellular phenotype. Through an ex vivo technology utilizing patient tumor and blood sample, we sought to understand the therapeutic potential of the kinase by recreating the tumor microenvironment. RESULTS: Using mass spectrometry-based high-throughput analysis, we identified 1,344 phosphosites and 848 phosphoproteins, including differential phosphorylation of 177 proteins (fold change cut-off ≥ 1.5). Our data showed that a subset of differentially phosphorylated proteins belonged to splicing machinery. Pathway analysis highlighted Cdc2-like kinase (CLK1) as upstream kinase. Inhibition of CLK1 using TG003 and CLK1 siRNA resulted in a decreased cell viability, proliferation, invasion and migration as well as modulation in the phosphorylation of SRSF2. Ex vivo experiments which utilizes patient's own tumor and blood to recreate the tumor microenvironment validated the use of CLK1 as a potential target for gastric cancer treatment. CONCLUSIONS: Our data indicates that CLK1 plays a crucial role in the regulation of splicing process in gastric cancer and that CLK1 can act as a novel therapeutic target in gastric cancer.


Assuntos
Fosfoproteínas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteoma/metabolismo , Neoplasias Gástricas/patologia , Animais , Apoptose , Biomarcadores Tumorais , Movimento Celular , Proliferação de Células , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Camundongos SCID , Invasividade Neoplásica , Fosforilação , Prognóstico , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/antagonistas & inibidores , Proteínas Tirosina Quinases/genética , Proteoma/análise , RNA Interferente Pequeno/genética , Neoplasias Gástricas/metabolismo , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
4.
Exp Cell Res ; 378(2): 206-216, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-30772380

RESUMO

Metastatic progression is a major cause of mortality in cervical cancers, but factors regulating migratory and pre-metastatic cell populations remain poorly understood. Here, we sought to assess whether a SUV39H1-low chromatin state promotes migratory cell populations in cervical cancers, using meta-analysis of data from The Cancer Genome Atlas (TCGA), immunohistochemistry, genomics and functional assays. Cervical cancer cells sorted based on migratory ability in vitro have low levels of SUV39H1 protein, and SUV39H1 knockdown in vitro enhanced cervical cancer cell migration. Further, TCGA SUV39H1-low tumours correlated with poor clinical outcomes and showed gene expression signatures of cell migration. SUV39H1 expression was examined within biopsies, and SUV39H1low cells within tumours also demonstrated migratory features. Next, to understand genome scale transcriptional and chromatin changes in migratory populations, cell populations sorted based on migration in vitro were examined using RNA-Seq, along with ChIP-Seq for H3K9me3, the histone mark associated with SUV39H1. Migrated populations showed SUV39H1-linked migratory gene expression signatures, along with broad depletion of H3K9me3 across gene promoters. We show for the first time that a SUV39H1-low chromatin state associates with, and promotes, migratory populations in cervical cancers. Our results posit SUV39H1-low cells as key populations for prognosis estimation and as targets for novel therapies.


Assuntos
Movimento Celular , Metiltransferases/fisiologia , Proteínas Repressoras/fisiologia , Neoplasias do Colo do Útero/patologia , Linhagem Celular Tumoral , Cromatina , Feminino , Técnicas de Silenciamento de Genes , Histonas/metabolismo , Humanos , Metiltransferases/genética , Metástase Neoplásica , Proteínas Repressoras/genética , Resultado do Tratamento
5.
Tumour Biol ; 40(5): 1010428318780859, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29888653

RESUMO

The goal of this study was to isolate cancer stem-like cells marked by high expression of CD44, a putative cancer stem cell marker, from primary oral squamous cell carcinomas and identify distinctive gene expression patterns in these cells. From 1 October 2013 to 4 September 2015, 76 stage III-IV primary oral squamous cell carcinoma of the gingivobuccal sulcus were resected. In all, 13 tumours were analysed by immunohistochemistry to visualise CD44-expressing cells. Expression of CD44 within The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma RNA-sequencing data was also assessed. Seventy resected tumours were dissociated into single cells and stained with antibodies to CD44 as well as CD45 and CD31 (together referred as Lineage/Lin). From 45 of these, CD44+Lin- and CD44-Lin- subpopulations were successfully isolated using fluorescence-activated cell sorting, and good-quality RNA was obtained from 14 such sorted pairs. Libraries from five pairs were sequenced and the results analysed using bioinformatics tools. Reverse transcription quantitative polymerase chain reaction was performed to experimentally validate the differential expression of selected candidate genes identified from the transcriptome sequencing in the same 5 and an additional 9 tumours. CD44 was expressed on the surface of poorly differentiated tumour cells, and within the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma samples, its messenger RNA levels were higher in tumours compared to normal. Transcriptomics revealed that 102 genes were upregulated and 85 genes were downregulated in CD44+Lin- compared to CD44-Lin- cells in at least 3 of the 5 tumours sequenced. The upregulated genes included those involved in immune regulation, while the downregulated genes were enriched for genes involved in cell adhesion. Decreased expression of PCDH18, MGP, SPARCL1 and KRTDAP was confirmed by reverse transcription quantitative polymerase chain reaction. Lower expression of the cell-cell adhesion molecule PCDH18 correlated with poorer overall survival in the The Cancer Genome Atlas-Head and Neck Squamous Cell Carcinoma data highlighting it as a potential negative prognostic factor in this cancer.


Assuntos
Caderinas/biossíntese , Carcinoma de Células Escamosas/genética , Adesão Celular/genética , Receptores de Hialuronatos/genética , Neoplasias Bucais/genética , Células-Tronco Neoplásicas/patologia , Ácido Aspártico Endopeptidases/biossíntese , Biomarcadores Tumorais/imunologia , Proteínas de Ligação ao Cálcio/biossíntese , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Proteínas da Matriz Extracelular/biossíntese , Citometria de Fluxo , Regulação Neoplásica da Expressão Gênica/genética , Papillomavirus Humano 16/genética , Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/genética , Papillomavirus Humano 18/isolamento & purificação , Humanos , Receptores de Hialuronatos/imunologia , Receptores de Hialuronatos/metabolismo , Antígenos Comuns de Leucócito/imunologia , Neoplasias Bucais/patologia , Molécula-1 de Adesão Celular Endotelial a Plaquetas/imunologia , Protocaderinas , RNA Mensageiro/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína de Matriz Gla
6.
Neurol India ; 66(3): 733-738, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29766934

RESUMO

BACKGROUND: While brain metastases (BM) are the most common causes of neurologic disorders in patients with known systemic malignancies, they can often be the initial manifestations of an undetected primary elsewhere. BM are major causes of morbidity and mortality in cancer patients. AIMS: We describe a mixed population (data from both retrospective and prospective collection) having a BM from a solid tumor. We report the percentage distribution of the most frequent types of BM, confirming the data published in the literature. This paper may play a role in presenting the Southeast Asian reality compared with the Western countries. SETTING: A tertiary-care cancer centre. MATERIALS AND METHODS: Data for 4 years were retrieved from the records of the Department of Pathology of our institute. Hematolymphoid and meningeal tumors were excluded. Hematoxylin and eosin (H and E) stained slides were reviewed, and in cases with an unknown primary, immunohistochemistry (IHC) was advised. The panel of markers was chosen based on the histomorphology on H and E sections. IHC was done in cases with an unknown primary where paraffin blocks were available. RESULTS: Lung cancer was found to be the most common primary malignancy (n = 30; 48.4%) followed by breast cancer (n = 13; 21%), colorectal cancer (n = 6; 9.6%), and skin cancer (melanoma) [n = 3; 4.8%]. CONCLUSION: The incidence of BM from lung and breast cancer was similar to that seen in the Western studies. However, BM from colorectal cancer and melanoma show a higher and lower incidence, respectively, in comparison with the Western literature.


Assuntos
Neoplasias Encefálicas/epidemiologia , Neoplasias Encefálicas/secundário , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Centros de Atenção Terciária , Adulto Jovem
7.
ScientificWorldJournal ; 2015: 325721, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26788548

RESUMO

The development of esophageal squamous cell carcinoma (ESCC) is poorly understood and the major regulatory molecules involved in the process of tumorigenesis have not yet been identified. We had previously employed a quantitative proteomic approach to identify differentially expressed proteins in ESCC tumors. A total of 238 differentially expressed proteins were identified in that study including S100 calcium binding protein A9 (S100A9) as one of the major downregulated proteins. In the present study, we carried out immunohistochemical validation of S100A9 in a large cohort of ESCC patients to determine the expression and subcellular localization of S100A9 in tumors and adjacent normal esophageal epithelia. Downregulation of S100A9 was observed in 67% (n = 192) of 288 different ESCC tumors, with the most dramatic downregulation observed in the poorly differentiated tumors (99/111). Expression of S100A9 was restricted to the prickle and functional layers of normal esophageal mucosa and localized predominantly in the cytoplasm and nucleus whereas virtually no expression was observed in the tumor and stromal cells. This suggests the important role that S100A9 plays in maintaining the differentiated state of epithelium and suggests that its downregulation may be associated with increased susceptibility to tumor formation.


Assuntos
Calgranulina B/metabolismo , Carcinoma de Células Escamosas/metabolismo , Regulação para Baixo , Neoplasias Esofágicas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Calgranulina B/genética , Carcinoma de Células Escamosas/patologia , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Células Epiteliais/metabolismo , Neoplasias Esofágicas/patologia , Humanos , Pessoa de Meia-Idade
8.
Biochim Biophys Acta ; 1834(11): 2308-16, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23665456

RESUMO

Protein biomarker discovery for early detection of head and neck squamous cell carcinoma (HNSCC) is a crucial unmet need to improve patient outcomes. Mass spectrometry-based proteomics has emerged as a promising tool for identification of biomarkers in different cancer types. Proteins secreted from cancer cells can serve as potential biomarkers for early diagnosis. In the current study, we have used isobaric tag for relative and absolute quantitation (iTRAQ) labeling methodology coupled with high resolution mass spectrometry to identify and quantitate secreted proteins from a panel of head and neck carcinoma cell lines. In all, we identified 2,472 proteins, of which 225 proteins were secreted at higher or lower abundance in HNSCC-derived cell lines. Of these, 148 were present in higher abundance and 77 were present in lower abundance in the cancer-cell derived secretome. We detected a higher abundance of some previously known markers for HNSCC including insulin like growth factor binding protein 3, IGFBP3 (11-fold) and opioid growth factor receptor, OGFR (10-fold) demonstrating the validity of our approach. We also identified several novel secreted proteins in HNSCC including olfactomedin-4, OLFM4 (12-fold) and hepatocyte growth factor activator, HGFA (5-fold). IHC-based validation was conducted in HNSCC using tissue microarrays which revealed overexpression of IGFBP3 and OLFM4 in 70% and 75% of the tested cases, respectively. Our study illustrates quantitative proteomics of secretome as a robust approach for identification of potential HNSCC biomarkers. This article is part of a Special Issue entitled: An Updated Secretome.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Proteoma/metabolismo , Proteômica/métodos , Biomarcadores Tumorais/análise , Linhagem Celular Tumoral , Cabeça/patologia , Humanos , Espectrometria de Massas/métodos , Pescoço/patologia , Proteoma/análise , Via Secretória , Carcinoma de Células Escamosas de Cabeça e Pescoço
9.
Cancers (Basel) ; 15(13)2023 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-37444412

RESUMO

Esophageal squamous cell carcinoma (ESCC) is a heterogeneous cancer associated with a poor prognosis in advanced stages. In India, it is the sixth most common cause of cancer-related mortality. In this study, we employed high-resolution mass spectrometry-based quantitative proteomics to characterize the differential protein expression pattern associated with ESCC. We identified several differentially expressed proteins including PDPN, TOP2A, POSTN and MMP2 that were overexpressed in ESCC. In addition, we identified downregulation of esophagus tissue-enriched proteins such as SLURP1, PADI1, CSTA, small proline-rich proteins such as SPRR3, SPRR2A, SPRR1A, KRT4, and KRT13, involved in squamous cell differentiation. We identified several overexpressed proteins mapped to the 3q24-29 chromosomal region, aligning with CNV alterations in this region reported in several published studies. Among these, we identified overexpression of SOX2, TP63, IGF2BP2 and RNF13 that are encoded by genes in the 3q26 region. Functional enrichment analysis revealed proteins involved in cell cycle pathways, DNA replication, spliceosome, and DNA repair pathways. We identified the overexpression of multiple proteins that play a major role in alleviating ER stress, including SYVN1 and SEL1L. The SYVN1/SEL1L complex is an essential part of the ER quality control machinery clearing misfolded proteins from the ER. SYVN1 is an E3 ubiquitin ligase that ubiquitinates ER-resident proteins. Interestingly, there are also other non-canonical substrates of SYVN1 which are known to play a crucial role in tumor progression. Thus, SYVN1 could be a potential therapeutic target in ESCC.

10.
Cells ; 11(10)2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35626709

RESUMO

ER-positive (ER+) breast cancer is considered immunologically 'silent' with fewer tumor-infiltrating immune cells. We have previously demonstrated the role of miR-18a in mediating invasion and poor prognosis in ER+ breast cancer by activation of the Wnt signaling pathway. Here, we explored the immune-modulatory functions of high levels of miR-18a in these tumors. A microarray-based gene expression analysis performed in miR-18a over-expressed ER+ breast cancer cell lines demonstrated dysregulation and suppression of immune-related pathways. Stratification of the ER+ tumor samples by miR-18a levels in the TCGA and METABRIC cohort and immune cell identification performed using CIBERSORT and Immune CellAI algorithms revealed a higher proportion of T-regulatory cells (p < 0.001) and a higher CD4/CD8 ratio (p < 0.01). miR-18a over-expressed MCF7 co-cultured with THP-1 showed decreased antigen presentation abilities and increased invasiveness and survival. They also promoted the differentiation of pro-tumorigenic M2 macrophages. Inhibition of the Wnt pathway in miR-18a over-expressed cells brought about the restoration of TAP-1, a protein critical for antigen presentation. Examination of tumor specimens from our case series showed that miR-18a high ER+ tumors had a dense lymphocyte infiltrate when compared to miR-18a low tumors but expressed a higher CD4/CD8 ratio and the M2 macrophage marker CD206, along with the invasive marker MMP9. We report for the first time an association between miR-18a-mediated Wnt signaling and stromal immune modulation in ER+ tumors. Our results highlight the possibility of formulating specific Wnt pathway inhibitors that may be used in combination with immune checkpoint blockers (ICB) for sensitizing 'immune-cold' ER+ tumors to immunotherapy.


Assuntos
Neoplasias da Mama , MicroRNAs , Neoplasias da Mama/patologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Evasão da Resposta Imune , MicroRNAs/metabolismo , Via de Sinalização Wnt
11.
Eur J Breast Health ; 18(1): 21-29, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35059588

RESUMO

OBJECTIVE: The interaction between programmed cell death protein 1 (PD-1) on activated T-lymphocytes and programmed death-ligand 1 (PD-L1) on tumor cells or antigen-presenting cells sends immunosuppressive signals leading to the escape of tumor cells from the host anti-tumor immune response. Inhibiting this interaction with antibodies against PD-1 or PD-L1 is emerging as a valuable therapeutic strategy. However, tissue distribution patterns for PD-L1 and PD-1 in breast cancer patients from India are not reported, yet many clinical trials are underway. In this study the expression of PD-1 and PD-L1 in breast cancer patient samples from India was characterized. MATERIALS AND METHODS: The study included 392 cases of operated breast cancer (2012-2017) from a tertiary cancer care center in Bangalore, Karnataka, India. Paraffin blocks were retrievable and receptor status was known. Immunohistochemistry (IHC) was performed using anti-PD-L1 and anti-PD-1 antibodies. RNA was isolated from 76 fresh tumors and nine adjacent normal tissues (2019). PD-L1 transcript levels were measured by RT-qPCR using Hypoxanthine-guanine phosphoribosyl transferase (HPRT) as a reference gene. RESULTS: Based on IHC, PD-1 expression within tumor-infiltrating immune cells (TIICs) was observed in 55/385 cases (14%) across all breast cancer types. In triple-negative breast cancer (TNBC), 21/132 cases (16%) showed PD-1 staining in TIICs. The overall expression of PD-L1 in breast tumor cells across all breast cancer subtypes and TIICs was 11% (41/378) and 39% (151/385), respectively. A relatively higher proportion of TNBC cases had PD-L1 expression in tumor cells (17/132 cases, 13%) and immune cells (68/132 cases, 52%). We also detected PD-L1 transcript expression by qRT-PCR in freshly isolated tumor samples. CONCLUSION: These findings show that around 52% (68/132) of the TNBC cases express PD-L1 in TIICs. Hence, anti-PD-1/PD-L1 therapy alone or combined with chemotherapy may be a promising treatment for TNBC in Indian patients.

12.
ACS Chem Biol ; 17(6): 1376-1386, 2022 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-35605245

RESUMO

Aberrations in glycan and lectin expression and function represent one of the earliest hallmarks of cancer. Among galectins, a conserved family of ß-galactoside-binding lectins, the role of Galectin-9 in immune-tumor interactions is well-established, although its effect on cancer cell behavior remains unclear. In this study, we assayed for, and observed, an association between Galectin-9 expression and invasiveness of breast cancer cells in vitro and in vivo. Genetic perturbation and pharmacological inhibition using novel cognate inhibitors confirmed a positive correlation between Galectin-9 levels and the adhesion of invasive cancer cells to─and their invasion through─constituted organomimetic extracellular matrix microenvironments. Signaling experiments and unbiased quantitative proteomics revealed Galectin-9 induction of Focal Adhesion Kinase activity and S100A4 expression, respectively. FAK inhibition decreased S100A4 mRNA levels. Our results provide crucial insights into how elevated Galectin-9 expression potentiates the invasiveness of breast cancer cells during early steps of invasion.


Assuntos
Neoplasias da Mama , Neoplasias da Mama/metabolismo , Matriz Extracelular/metabolismo , Feminino , Galectinas/genética , Galectinas/metabolismo , Humanos , Polissacarídeos/metabolismo , Transdução de Sinais , Microambiente Tumoral
13.
ACS Cent Sci ; 7(1): 110-125, 2021 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-33532574

RESUMO

Heterogeneity in phenotypes of malignantly transformed cells and aberrant glycan expression on their surface are two prominent hallmarks of cancers that have hitherto not been linked to each other. In this paper, we identify differential levels of a specific glycan linkage: α2,6-linked sialic acids within breast cancer cells in vivo and in culture. Upon sorting out two populations with moderate, and relatively higher, cell surface α2,6-linked sialic acid levels from the triple-negative breast cancer cell line MDA-MB-231, both populations (denoted as medium and high 2,6-Sial cells, respectively) stably retained their levels in early passages. Upon continuous culturing, medium 2,6-Sial cells recapitulated the heterogeneity of the unsorted line whereas high 2,6-Sial cells showed no such tendency. Compared with high 2,6-Sial cells, the medium 2,6-Sial counterparts showed greater adhesion to reconstituted extracellular matrices (ECMs) and invaded faster as single cells. The level of α2,6-linked sialic acids in the two sublines was found to be consistent with the expression of a specific glycosyl transferase, ST6GAL1. Stably knocking down ST6GAL1 in the high 2,6-Sial cells enhanced their invasiveness. When cultured together, medium 2,6-Sial cells differentially migrated to the edge of growing tumoroid-like cocultures, whereas high 2,6-Sial cells formed the central bulk. Multiscale simulations in a Cellular Potts model-based computational environment calibrated to our experimental findings suggest that differential levels of cell-ECM adhesion, likely regulated by α2,6-linked sialic acids, facilitate niches of highly invasive cells to efficiently migrate centrifugally as the invasive front of a malignant breast tumor.

14.
Front Oncol ; 10: 1457, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32974170

RESUMO

Esophageal squamous cell carcinoma (ESCC) is the most common histological subtype of esophageal cancer in India. Cigarette smoking and chewing tobacco are known risk factors associated with ESCC. However, genomic alterations associated with ESCC in India are not well-characterized. In this study, we carried out exome sequencing to characterize the mutational landscape of ESCC tumors from subjects with a varied history of tobacco usage. Whole exome sequence analysis of ESCC from an Indian cohort revealed several genes that were mutated or had copy number changes. ESCC from tobacco chewers had a higher frequency of C:G > A:T transversions and 2-fold enrichment for mutation signature 4 compared to smokers and non-users of tobacco. Genes, such as TP53, CSMD3, SYNE1, PIK3CA, and NOTCH1 were found to be frequently mutated in Indian cohort. Mutually exclusive mutation patterns were observed in PIK3CA-NOTCH1, DNAH5-ZFHX4, MUC16-FAT1, and ZFHX4-NOTCH1 gene pairs. Recurrent amplifications were observed in 3q22-3q29, 11q13.3-q13.4, 7q22.1-q31.1, and 8q24 regions. Approximately 53% of tumors had genomic alterations in PIK3CA making this pathway a promising candidate for targeted therapy. In conclusion, we observe enrichment of mutation signature 4 in ESCC tumors from patients with a history of tobacco chewing. This is likely due to direct exposure of esophagus to tobacco carcinogens when it is chewed and swallowed. Genomic alterations were frequently observed in PIK3CA-AKT pathway members independent of the history of tobacco usage. PIK3CA pathway can be potentially targeted in ESCC which currently has no effective targeted therapeutic options.

15.
Front Oncol ; 10: 1666, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33251127

RESUMO

Though smoking remains one of the established risk factors of esophageal squamous cell carcinoma, there is limited data on molecular alterations associated with cigarette smoke exposure in esophageal cells. To investigate molecular alterations associated with chronic exposure to cigarette smoke, non-neoplastic human esophageal epithelial cells were treated with cigarette smoke condensate (CSC) for up to 8 months. Chronic treatment with CSC increased cell proliferation and invasive ability of non-neoplastic esophageal cells. Whole exome sequence analysis of CSC treated cells revealed several mutations and copy number variations. This included loss of high mobility group nucleosomal binding domain 2 (HMGN2) and a missense variant in mediator complex subunit 1 (MED1). Both these genes play an important role in DNA repair. Global proteomic and phosphoproteomic profiling of CSC treated cells lead to the identification of 38 differentially expressed and 171 differentially phosphorylated proteins. Bioinformatics analysis of differentially expressed proteins and phosphoproteins revealed that most of these proteins are associated with DNA damage response pathway. Proteomics data revealed decreased expression of HMGN2 and hypophosphorylation of MED1. Exogenous expression of HMGN2 and MED1 lead to decreased proliferative and invasive ability of smoke exposed cells. Immunohistochemical labeling of HMGN2 in primary ESCC tumor tissue sections (from smokers) showed no detectable expression while strong to moderate staining of HMGN2 was observed in normal esophageal tissues. Our data suggests that cigarette smoke perturbs expression of proteins associated with DNA damage response pathways which might play a vital role in development of ESCC.

16.
Mol Cancer ; 8: 128, 2009 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-20030805

RESUMO

BACKGROUND: Recent studies have implicated aberrant Notch signaling in breast cancers. Yet, relatively little is known about the pattern of expression of various components of the Notch pathway, or its mechanism of action. To better understand the role of the Notch pathway in breast cancer, we have undertaken a detailed expression analysis of various Notch receptors, their ligands, and downstream targets at different stages of breast cancer progression. RESULTS: We report here that there is a general increase in the expression levels of Notch 1, 2, 4, Jagged1, Jagged2, and Delta-like 4 proteins in breast cancers, with simultaneous upregulation of multiple Notch receptors and ligands in a given cancer tissue. While Notch3 and Delta-like1 were undetectable in normal tissues, moderate to high expression was detected in several cancers. We detected the presence of active, cleaved Notch1, along with downstream targets of the Notch pathway, Hes1/Hes5, in approximately 75% of breast cancers, clearly indicating that in a large proportion of breast cancers Notch signaling is aberrantly activated. Furthermore, we detected cleaved Notch1 and Hes1/5 in early precursors of breast cancers - hyperplasia and ductal carcinoma in situ - suggesting that aberrant Notch activation may be an early event in breast cancer progression. Mechanistically, while constitutively active Notch1 alone failed to transform immortalized breast cells, it synergized with the Ras/MAPK pathway to mediate transformation. This cooperation is reflected in vivo, as a subset of cleaved Notch positive tumors additionally expressed phopsho-Erk1/2 in the nuclei. Such cases exhibited high node positivity, suggesting that Notch-Ras cooperation may lead to poor prognosis. CONCLUSIONS: High level expression of Notch receptors and ligands, and its increased activation in several breast cancers and early precursors, places Notch signaling as a key player in breast cancer pathogenesis. Its cooperation with the Ras/MAPK pathway in transformation offers combined inhibition of the two pathways as a new modality for breast cancer treatment.


Assuntos
Neoplasias da Mama/metabolismo , Sistema de Sinalização das MAP Quinases , Proteína Oncogênica p21(ras)/metabolismo , Receptores Notch/metabolismo , Transdução de Sinais , Neoplasias da Mama/enzimologia , Neoplasias da Mama/patologia , Transformação Celular Neoplásica , Progressão da Doença , Humanos , Ligantes
17.
Pediatr Blood Cancer ; 52(7): 881-3, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19165887

RESUMO

We report a rare case of cellular fetal rhabdomyoma in a 9-year-old male, in the unusual location of right lower thigh. These tumors are more common in the head and neck region; and this case the second such case to be reported in the thigh. Fetal rhabdomyoma is a benign tumor of the skeletal muscle, showing varying degrees of skeletal muscle maturation. The present report discusses the histopathological features, the differential diagnosis and the importance of making the correct diagnosis for proper management of this rare entity.


Assuntos
Extremidade Inferior/patologia , Rabdomioma/patologia , Criança , Humanos , Extremidade Inferior/embriologia , Masculino , Rabdomioma/embriologia
18.
South Asian J Cancer ; 8(2): 88-91, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31069185

RESUMO

CONTEXT: Pancreatic fistula has forever been a dreaded complication after pancreatic anastomosis (PA). We present a retrospective analysis of 10 years of experience with the Modified Heidelberg technique (MHT) that has been recently described. AIM: The aim of the study is to establish postoperative pancreatic fistula (POPF) rates after MHT. SETTINGS AND DESIGN: This is a retrospective observational study carried out at a tertiary cancer center in South India in the Department of Surgical Oncology. SUBJECTS AND METHODS: Two hundred and eight consecutive patients who underwent pancreaticoduodenectomy (PD) and PA with MHT for a variety of proximal pancreatic lesions from January 2008 to February 2018 were included in this study. The incidence of POPF was recorded by the International Study Group on Pancreatic Fistula 2005 and 2016 definitions. STATISTICAL ANALYSIS USED: Epidemiological and clinical data are expressed in ratios and percentage and presented in table format. RESULTS: Between January 2008 and March 2016, 186 patients underwent PD, and MHT was used for PA. Five (2.7%) patients developed Grade A POPF whereas Grades B and C were seen in three (1.6%) patients each with one death. Between April 2016 and February 2018, 22 patients underwent PD. Two patients (9%) had biochemical leak whereas none of them developed clinically relevant POPF. No deaths were recorded in this period. Overall, Grade B and Grade C POPF rates were 1.4% each, whereas 30-day mortality was 0.4%. CONCLUSIONS: Results of this study indicate that MHT is a safe, reliable, easy to learn, and adopt technique of pancreatic reconstruction after PD.

19.
J Gastrointest Oncol ; 10(2): 307-313, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31032099

RESUMO

BACKGROUND: Little has been reported regarding differences between malignancies that develop at the anastomotic site (ASC) and those that develop at the remnant stump (RSC) in gastric stump carcinomas (GSC). The purpose of our study was to compare clinical, pathological and survival characteristics of ASC patients with those of RSC patients. METHODS: Patients who underwent surgery for GSC between January 2005 and December 2017 were analyzed. Of the total 112 patients, 22 patients were excluded from the study due to extensive loss of data. Ninety patients underwent curative resection and were evaluated based on anatomic site at which they developed malignancy, i.e., ASC and RSC. Clinical, pathological and survival characteristics were assessed. RESULTS: As per Lauren's classification, diffuse and intestinal variety were significantly associated with ASC (P=0.0001) and RSC (P=0.0001) respectively. RSC was associated with lower pT [pT2, 15/33 (45.5%), P=0.0002]. ASC was significantly associated with higher pN [pN3, 30/57 (52.6%), P=0.0013], stage [stage III, 48/57 (84.2%), P=0.0022], positive mesenteric nodes (P=0.006) and poor 3-year survival (10.5% versus 36.4%, P=0.003). CONCLUSIONS: ASC is substantially different than RSC. ASC is more aggressive disease compared to RSC and has different pathophysiology, higher rates of nodal involvement (both primary and mesenteric), presents with higher stage and has significantly poor 3-year survival.

20.
Clin Breast Cancer ; 19(1): 27-34, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30217473

RESUMO

BACKGROUND: Homeostasis of telomere in breast cancer might be altered as a result of cumulative effects of various factors causing genomic instability and affecting prognosis. This study aimed to compare the relative telomere length (RTL) and hTERT mRNA expression in the tissue of patients with breast cancer along with the clinicopathologic parameters. PATIENTS AND METHODS: Frozen tumor tissues and adjacent normal breast tissue from 98 patients with invasive ductal breast cancer were used for the analysis. RTL and hTERT mRNA expression were measured using quantitative real time polymerase chain reaction. RESULTS: Among the 98 cases, 51% had an early-stage carcinoma, 66% were tumor size < 5 cm, 30% were node-negative, and 20% were low-grade tumors. In this study, 63% of cases showed higher hTERT gene expression with an odds ratio of 2.77 (P = .02). The median RTL for elongated telomere was 3.49, and the value was significantly elevated when compared with the shorter telomere. Shortened RTL was present in 60% of early-stage cancer cases, 55% where the tumor size was < 5 cm, 72% of the lymph node-negative cases, and 68% of low-grade carcinoma. Significantly elongated RTL, with median 4.22, 3.19, 3.17, and 3.28 was observed (P < .05) in the advanced stage, larger tumor size, node-positive, and high-grade cases respectively. CONCLUSION: In this study, shortened telomere was observed in early-stage cancer, and elongated telomere was found in advanced diseases. However, 13% of patients with lower hTERT gene expression showed elongated telomeres, indicating relative telomere length measurement in tissue is different from blood leukocyte, showing the dynamic process of tumorigenesis in tissue.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/patologia , Telomerase/genética , Encurtamento do Telômero/genética , Adulto , Neoplasias da Mama/genética , Neoplasias da Mama/cirurgia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/cirurgia , Carcinoma Lobular/genética , Carcinoma Lobular/cirurgia , Estudos de Casos e Controles , Estudos Transversais , Feminino , Seguimentos , Humanos , Gradação de Tumores , Estadiamento de Neoplasias , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
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