Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Biol Open ; 12(5)2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37194999

RESUMO

Head and neck cancer (HNC) differs at anatomical sites and hypopharyngeal cancer (HPC) is a type of HNC. The non-surgical treatment option for advanced cases of HPC is radiotherapy (RT) with or without chemotherapy but survival is poor. Thus, new treatment approaches in combination with RT are essential. Yet, obtaining post-RT treated tumour specimens and lack of animal models with identical anatomical sites are the major translational research barriers. To overcome these barriers, for the first time, we have developed a tumour-stroma based in vitro three-dimensional (3D)-tumouroid co-culture model of HPC by growing FaDu and HS-5 cells together to mimic the complex tumour-microenvironment in a Petri dish. Before growing the cells together, imaging flow cytometry revealed distinct epithelial and non-epithelial characteristics of the cells. Growth rate of the 3D-tumouroid co-culture was significantly higher compared to the tumouroid monoculture of FaDu. Histology and morphometric analysis were done for the characterisation as well as the development of hypoxia was measured by CAIX immunostaining in this 3D-tumouroid co-culture. Taken together, this innovative in vitro 3D model of HPC resembles many features of the original tumour. The wider application of this pre-clinical research tool is in understanding newer combination (e.g. immunotherapy) treatment approaches with RT in HPC and beyond.


Assuntos
Neoplasias Hipofaríngeas , Animais , Técnicas de Cocultura , Neoplasias Hipofaríngeas/terapia , Bioengenharia , Microambiente Tumoral
2.
Cancers (Basel) ; 13(6)2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33804647

RESUMO

Defective DNA damage response (DDR) pathways are enabling characteristics of cancers that not only can be exploited to specifically target cancer cells but also can predict chemotherapy response. Defective Homologous Recombination Repair (HRR) function, e.g., due to BRCA1/2 loss, is a determinant of response to platinum agents and PARP inhibitors in ovarian cancers. Most chemotherapies function by either inducing DNA damage or impacting on its repair but are generally used in the clinic unselectively. The significance of HRR and other DDR pathways in determining response to several other chemotherapy drugs is not well understood. In this study, the genomic, transcriptomic and functional analysis of DDR pathways in a panel of 14 ovarian cancer cell lines identified that defects in DDR pathways could determine response to several chemotherapy drugs. Carboplatin, rucaparib, and topotecan sensitivity were associated with functional loss of HRR (validated in 10 patient-derived primary cultures) and mismatch repair. Two DDR gene expression clusters correlating with treatment response were identified, with PARP10 identified as a novel marker of platinum response, which was confirmed in The Cancer Genome Atlas (TCGA) ovarian cancer cohort. Reduced non-homologous end-joining function correlated with increased sensitivity to doxorubicin, while cells with high intrinsic oxidative stress showed sensitivity to gemcitabine. In this era of personalised medicine, molecular/functional characterisation of DDR pathways could guide chemotherapy choices in the clinic allowing specific targeting of ovarian cancers.

3.
J Clin Pathol ; 74(7): 469-474, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33214200

RESUMO

In an era when immunohistochemistry (IHC) is increasingly depended on for histological subtyping, and IHC-determined biomarker informing rapid treatment choices is on the horizon; reproducible, quantifiable techniques are required. This study aimed to compare automated IHC scoring to quantify 6 DNA damage response protein markers using a tissue microarray of 66 ovarian cancer samples. Accuracy of quantification was compared between manual H-score and computer-aided quantification using Aperio ImageScope with and without a tissue classification algorithm. High levels of interobserver variation was seen with manual scoring. With automated methods, inclusion of the tissue classifier mask resulted in greater accuracy within carcinomatous areas and an overall increase in H-score of a median of 11.5% (0%-18%). Without the classifier, the score was underestimated by a median of 10.5 (5.2-25.6). Automated methods are reliable and superior to manual scoring. Fixed algorithms offer the reproducibility needed for high-throughout clinical applications.


Assuntos
Algoritmos , Biomarcadores Tumorais/análise , Diagnóstico por Computador/métodos , Interpretação de Imagem Assistida por Computador/métodos , Neoplasias Ovarianas/diagnóstico , Feminino , Humanos , Imuno-Histoquímica/métodos
4.
Cancers (Basel) ; 12(7)2020 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-32709004

RESUMO

In order to be effective models to identify biomarkers of chemotherapy response, cancer cell lines require thorough characterization. In this study, we characterised the widely used high grade serous ovarian cancer (HGSOC) cell line NIH-OVCAR3 using bioinformatics, cytotoxicity assays and molecular/functional analyses of DNA damage response (DDR) pathways in comparison to an ovarian cancer cell line panel. Bioinformatic analysis confirmed the HGSOC-like features of NIH-OVCAR3, including low mutation frequency, TP53 loss and high copy number alteration frequency similar to 201 HGSOCs analysed (TCGA). Cytotoxicity assays were performed for the standard of care chemotherapy, carboplatin, and DDR targeting drugs: rucaparib (a PARP inhibitor) and VE-821 (an ATR inhibitor). Interestingly, NIH-OVCAR3 cells showed sensitivity to carboplatin and rucaparib which was explained by functional loss of homologous recombination repair (HRR) identified by plasmid re-joining assay, despite the ability to form RAD51 foci and absence of mutations in HRR genes. NIH-OVCAR3 cells also showed high non-homologous end joining activity, which may contribute to HRR loss and along with genomic amplification in ATR and TOPBP1, could explain the resistance to VE-821. In summary, NIH-OVCAR3 cells highlight the complexity of HGSOCs and that genomic or functional characterization alone might not be enough to predict/explain chemotherapy response.

6.
Cancer Epidemiol ; 54: 31-37, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29571035

RESUMO

BACKGROUND: We undertook the current study on cervical Human Papillomavirus (HPV) prevalence along with cytology in women visiting the Gynecology Out-patient Department of a hospital for common gynecological ailments, subsequent to our earlier population-based study on HPV prevalence from India. METHODS: We analyzed data on cervical-cytology (Pap smears) and PCR-based molecular detection of HPV infection along with socio-demographic variables (N = 696). RESULTS: We identified 36.84% HPV-positive women amongst whom, HPV16 and 18 together predominated (79.37%) over other HPV types (20.63%). Contrarily, only 6.4% women revealed abnormal cytological lesions, of which, 46.51% were HPV-positive and 95% of such women harbored HPV16/18, while 5% harbored other HPV types. Individuals with normal cytology portrayed 36.09% HPV infections, of which, 77.97% were HPV16/18-positive and 22.03% harbored other HPV types. Overall HPV prevalence decreased significantly (ptrend  = 0.047) with increase in age, but HPV16/18 infections were significantly over-represented compared to the other HPV types across all age-groups. Specifically, HPV16 prevalence increased (p trend < 0.01) with increase in severity of cervical lesions. HPV16 prevalence did not differ between the Hindus and Muslims but HPV18 was significantly higher among the cytologically normal Muslim women (24.14%, p = 0.02), compared to the Hindus (11.91%), specifically among those ≥ 30 years of age. There was a significant (p < 0.05) overrepresentation of HPV16 prevalence among women who were users of oral contraceptive-pills, irrespective of cytology. CONCLUSIONS: Our study highlights the need for HPV16/18-based screening of cervical cancers in India considering the immense socio-cultural and genetic diversity at the population level.


Assuntos
Papillomavirus Humano 16/isolamento & purificação , Papillomavirus Humano 18/isolamento & purificação , Programas de Rastreamento/métodos , Infecções por Papillomavirus/epidemiologia , Adulto , Distribuição por Idade , Feminino , Humanos , Índia/epidemiologia , Pessoa de Meia-Idade , Infecções por Papillomavirus/virologia , Reação em Cadeia da Polimerase , Prevalência , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/patologia , Esfregaço Vaginal
7.
Cell Oncol (Dordr) ; 39(6): 559-572, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27683269

RESUMO

PURPOSE: Previously, over-expression of the long noncoding RNA (lncRNA) HOTAIR has been found to be associated with the invasive and metastatic capacities of several epithelial cancers, including cervical cancer (CaCx). Here, we aimed at identifying functionally relevant genetic variants that may be employed to differentiate between clinically distinct CaCx subtypes, i.e., those exhibiting high HOTAIR levels and molecular signatures of metastasis and those lacking such signatures in the presence of low HOTAIR expression levels. METHODS: Genomic DNA isolated from various cervical tissue samples (characterized by histopathology and HPV status) was used for HOTAIR amplicon sequencing, followed by validation of the findings by Sanger sequencing. The impact of the genetic variants found on the secondary structure of HOTAIR and the concomitant alterations in miRNA binding sites were determined through in silico analysis, followed by miRNA expression analysis by quantitative real-time PCR and confirmation of miRNA binding using a luciferase reporter assay. RESULTS: We found that rs2366152C was over-represented [ORage-adjusted = 2.58 (1.23-5.57); p = 0.014] in low HOTAIR expressing HPV positive CaCx cases compared to HPV negative controls. This genetic variant showed the propensity of a secondary structure alteration and gain of a miR-22 binding site in HOTAIR, which was found to be concordant with miR-22 over-expression in low HOTAIR CaCx cases compared to controls. We found that miR-22 expression negatively correlated with HOTAIR and E7 expression in HPV16 positive cases and in an E7 transfected HPV negative CaCx-derived cell line (C33A), but was not altered in high HOTAIR cases compared to controls. Reduced luciferase activity of a HOTAIR rs2366152C expression plasmid in C33A cells through miR-22 co-transfection confirmed the ability of miR-22 to specifically target rs2366152C-harbouring HOTAIR lncRNA in CaCx cells, ultimately leading to its down-regulation. CONCLUSIONS: Our data indicate that rs2366152C not only has the potential to serve as a marker for singling out CaCx cases lacking metastatic molecular signatures, but also to explain the functional inactivation of HOTAIR in these cases, including the mechanism of its down-regulation.


Assuntos
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Polimorfismo de Nucleotídeo Único/genética , RNA Longo não Codificante/genética , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia , Adulto , Idoso , Carcinoma de Células Escamosas/virologia , Regulação para Baixo , Feminino , Papillomavirus Humano 16 , Humanos , Pessoa de Meia-Idade , Infecções por Papillomavirus/complicações , Reação em Cadeia da Polimerase em Tempo Real , Neoplasias do Colo do Útero/virologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...