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1.
BMJ Open Gastroenterol ; 11(1)2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302475

RESUMO

OBJECTIVE: Coeliac disease (CD) diagnosis generally depends on histological examination of duodenal biopsies. We present the first study analysing the concordance in examination of duodenal biopsies using digitised whole-slide images (WSIs). We further investigate whether the inclusion of immunoglobulin A tissue transglutaminase (IgA tTG) and haemoglobin (Hb) data improves the interobserver agreement of diagnosis. DESIGN: We undertook a large study of the concordance in histological examination of duodenal biopsies using digitised WSIs in an entirely virtual reporting setting. Our study was organised in two phases: in phase 1, 13 pathologists independently classified 100 duodenal biopsies (40 normal; 40 CD; 20 indeterminate enteropathy) in the absence of any clinical or laboratory data. In phase 2, the same pathologists examined the (re-anonymised) WSIs with the inclusion of IgA tTG and Hb data. RESULTS: We found the mean probability of two observers agreeing in the absence of additional data to be 0.73 (±0.08) with a corresponding Cohen's kappa of 0.59 (±0.11). We further showed that the inclusion of additional data increased the concordance to 0.80 (±0.06) with a Cohen's kappa coefficient of 0.67 (±0.09). CONCLUSION: We showed that the addition of serological data significantly improves the quality of CD diagnosis. However, the limited interobserver agreement in CD diagnosis using digitised WSIs, even after the inclusion of IgA tTG and Hb data, indicates the importance of interpreting duodenal biopsy in the appropriate clinical context. It further highlights the unmet need for an objective means of reproducible duodenal biopsy diagnosis, such as the automated analysis of WSIs using artificial intelligence.


Assuntos
Doença Celíaca , Humanos , Doença Celíaca/diagnóstico , Transglutaminases , Inteligência Artificial , Variações Dependentes do Observador , Imunoglobulina A
2.
Nat Genet ; 54(12): 1827-1838, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36175792

RESUMO

We identify the sodium leak channel non-selective protein (NALCN) as a key regulator of cancer metastasis and nonmalignant cell dissemination. Among 10,022 human cancers, NALCN loss-of-function mutations were enriched in gastric and colorectal cancers. Deletion of Nalcn from gastric, intestinal or pancreatic adenocarcinomas in mice did not alter tumor incidence, but markedly increased the number of circulating tumor cells (CTCs) and metastases. Treatment of these mice with gadolinium-a NALCN channel blocker-similarly increased CTCs and metastases. Deletion of Nalcn from mice that lacked oncogenic mutations and never developed cancer caused shedding of epithelial cells into the blood at levels equivalent to those seen in tumor-bearing animals. These cells trafficked to distant organs to form normal structures including lung epithelium, and kidney glomeruli and tubules. Thus, NALCN regulates cell shedding from solid tissues independent of cancer, divorcing this process from tumorigenesis and unmasking a potential new target for antimetastatic therapies.


Assuntos
Neoplasias , Humanos , Camundongos , Animais , Canais Iônicos/genética , Proteínas de Membrana/genética
3.
Nat Metab ; 3(9): 1150-1162, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34531575

RESUMO

Macrophages exhibit a spectrum of activation states ranging from classical to alternative activation1. Alternatively, activated macrophages are involved in diverse pathophysiological processes such as confining tissue parasites2, improving insulin sensitivity3 or promoting an immune-tolerant microenvironment that facilitates tumour growth and metastasis4. Recently, the metabolic regulation of macrophage function has come into focus as both the classical and alternative activation programmes require specific regulated metabolic reprogramming5. While most of the studies regarding immunometabolism have focussed on the catabolic pathways activated to provide energy, little is known about the anabolic pathways mediating macrophage alternative activation. In this study, we show that the anabolic transcription factor sterol regulatory element binding protein 1 (SREBP1) is activated in response to the canonical T helper 2 cell cytokine interleukin-4 to trigger the de novo lipogenesis (DNL) programme, as a necessary step for macrophage alternative activation. Mechanistically, DNL consumes NADPH, partitioning it away from cellular antioxidant defences and raising reactive oxygen species levels. Reactive oxygen species serves as a second messenger, signalling sufficient DNL, and promoting macrophage alternative activation. The pathophysiological relevance of this mechanism is validated by showing that SREBP1/DNL is essential for macrophage alternative activation in vivo in a helminth infection model.


Assuntos
Antioxidantes/metabolismo , Ácidos Graxos/biossíntese , Macrófagos/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Animais , Dexametasona/farmacologia , Humanos , Interleucina-4/farmacologia , Lipopolissacarídeos/farmacologia , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Camundongos , Camundongos Knockout , Nippostrongylus/isolamento & purificação , Nippostrongylus/patogenicidade , Células RAW 264.7 , Análise de Sequência de RNA/métodos , Infecções por Strongylida/imunologia , Infecções por Strongylida/parasitologia , Regulação para Cima
4.
Health Technol Assess ; 24(40): 1-190, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32880572

RESUMO

BACKGROUND: The addition of adjuvant trastuzumab to chemotherapy has significantly improved outcomes for people with human epidermal growth factor receptor 2 (HER2)-positive, early, potentially curable breast cancer. Twelve months' trastuzumab, tested in registration trials, was adopted as standard adjuvant treatment in 2006. Subsequently, similar outcomes were demonstrated using 9 weeks of trastuzumab. Shorter durations were therefore tested for non-inferiority. OBJECTIVES: To establish whether or not 6 months' adjuvant trastuzumab is non-inferior to 12 months' in the treatment of HER2-positive early breast cancer using a primary end point of 4-year disease-free survival. DESIGN: This was a Phase III randomised controlled non-inferiority trial. SETTING: The setting was 152 NHS hospitals. PARTICIPANTS: A total of 4088 patients with HER2-positive early breast cancer who it was planned would receive both chemotherapy and trastuzumab took part. INTERVENTION: Randomisation (1 : 1) to 6 months' or 12 months' trastuzumab treatment. MAIN OUTCOMES: The primary end point was disease-free survival. The secondary end points were overall survival, cost-effectiveness and cardiac function during treatment with trastuzumab. Assuming a 4-year disease-free survival rate of 80% with 12 months' trastuzumab, 4000 patients were required to demonstrate non-inferiority of 6 months' trastuzumab (5% one-sided significance, 85% power), defining the non-inferiority limit as no worse than 3% below the standard arm. Costs and quality-adjusted life-years were estimated using a within-trial analysis and a lifetime decision-analytic model. RESULTS: Between 4 October 2007 and 31 July 2015, 2045 patients were randomised to 12 months' trastuzumab and 2043 were randomised to 6 months' trastuzumab. Sixty-nine per cent of patients had ER-positive disease; 90% received anthracyclines (49% with taxanes; 41% without taxanes); 10% received taxanes without anthracyclines; 54% received trastuzumab sequentially after chemotherapy; and 85% received adjuvant chemotherapy (58% were node negative). At 6.1 years' median follow-up, with 389 (10%) deaths and 566 (14%) disease-free survival events, the 4-year disease-free survival rates for the 4088 patients were 89.5% (95% confidence interval 88.1% to 90.8%) in the 6-month group and 90.3% (95% confidence interval 88.9% to 91.5%) in the 12-month group (hazard ratio 1.10, 90% confidence interval 0.96 to 1.26; non-inferiority p = 0.01), demonstrating non-inferiority of 6 months' trastuzumab. Congruent results were found for overall survival (non-inferiority p = 0.0003) and landmark analyses 6 months from starting trastuzumab [non-inferiority p = 0.03 (disease-free-survival) and p = 0.006 (overall survival)]. Six months' trastuzumab resulted in fewer patients reporting adverse events of severe grade [365/1929 (19%) vs. 460/1935 (24%) for 12-month patients; p = 0.0003] or stopping early because of cardiotoxicity [61/1977 (3%) vs. 146/1941 (8%) for 12-month patients; p < 0.0001]. Health economic analysis showed that 6 months' trastuzumab resulted in significantly lower lifetime costs than and similar lifetime quality-adjusted life-years to 12 months' trastuzumab, and thus there is a high probability that 6 months' trastuzumab is cost-effective compared with 12 months' trastuzumab. Patient-reported experiences in the trial highlighted fatigue and aches and pains most frequently. LIMITATIONS: The type of chemotherapy and timing of trastuzumab changed during the recruitment phase of the study as standard practice altered. CONCLUSIONS: PERSEPHONE demonstrated that, in the treatment of HER2-positive early breast cancer, 6 months' adjuvant trastuzumab is non-inferior to 12 months'. Six months' treatment resulted in significantly less cardiac toxicity and fewer severe adverse events. FUTURE WORK: Ongoing translational work investigates patient and tumour genetic determinants of toxicity, and trastuzumab efficacy. An individual patient data meta-analysis with PHARE and other trastuzumab duration trials is planned. TRIAL REGISTRATION: Current Controlled Trials ISRCTN52968807, EudraCT 2006-007018-39 and ClinicalTrials.gov NCT00712140. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 40. See the NIHR Journals Library website for further project information.


THE BACKGROUND: There are several different types of breast cancer and some are called 'HER2 positive'. These cancers can often be cured by treatment with chemotherapy and a drug called trastuzumab (also known as Herceptin®; Roche, Basel, Switzerland). Although the first trials of trastuzumab used 12 months treatment, we did not know if less treatment could work as well. A small trial in Finland showed that giving trastuzumab for just 9 weeks was also effective. We know that trastuzumab can have some side effects, including heart problems, so it was important to see if we could reduce the length of treatment time, which is usually 12 months. WHAT DID WE DO?: We wanted to find out if we could treat patients safely with 6 months rather than 12 months of trastuzumab. We carried out a clinical trial called PERSEPHONE, in which over 4000 patients with this type of early breast cancer took part. Half of the patients were given 12 months of trastuzumab and half were given 6 months of trastuzumab. WHAT DID WE FIND?: We found that the two groups of patients had very similar benefit from treatment. At 4 years after diagnosis 90.3% of those who had received 12 months of trastuzumab were alive and free of any breast cancer recurrence, compared with 89.5% of those who had received 6 months. In other words, 125 patients would need to be treated with 12 months' trastuzumab rather than 6 months' trastuzumab for one more person to be alive and cancer-free 4 years from diagnosis. THE SIDE EFFECTS?: Severe side effects of trastuzumab were seen on at least one occasion in 24% of 12-month patients compared with 19% of 6-month patients. More patients receiving 12 months of trastuzumab had to stop trastuzumab early because of heart problems (8% of 12-month patients compared with 3% of 6-month patients). WHAT DOES THIS ALL MEAN?: We have shown that 6 months of trastuzumab has similar outcomes to 12 months in treating patients with HER2-positive early breast cancer but with fewer severe side effects, including heart problems, fewer visits to hospital for patients and significant cost savings for the NHS.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante , Receptor ErbB-2 , Trastuzumab/administração & dosagem , Antineoplásicos Imunológicos/efeitos adversos , Análise Custo-Benefício , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Anos de Vida Ajustados por Qualidade de Vida , Receptor ErbB-2/genética , Fatores de Tempo , Trastuzumab/efeitos adversos
5.
ANZ J Surg ; 90(11): 2346-2352, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32808415

RESUMO

BACKGROUND: Pre-operative breast tumour radial dimensions often determine the choice between simple wide local excision (WLE) and oncoplastic breast surgery (OBS). We reviewed the three-dimensional interplay between tumour and surgical specimen dimensions in the two cohorts. METHODS: Demographic, tumour and treatment data were collected for all patients undergoing OBS by a single surgeon and compared with a randomly selected cohort of WLE patients treated. The relationship between tumour and specimen medio-lateral, supero-inferior and antero-posterior dimensions were explored in both groups. Subgroup analyses were performed in the OBS cohort (parenchymal displacement versus replacement). RESULTS: We identified 60 OBS patients (63 breasts), comparing them with 60 WLE patients. Pre-operative tumour estimated size was significantly larger in the OBS cohort and concordant with macroscopic tumour radial dimensions and final microscopic tumour size. Surgical specimen weight was more than 3.5 times higher in the OBS group and its radial dimensions were almost double. No significant difference was observed for the antero-posterior dimensions. The rate of margin re-excisions and completion mastectomies were lower in the OBS cohort. WLE patients with positive margins had a lower tumour-to-specimen ratio, whereas, the requirement for further surgery in the OBS cohort was associated with larger tumour dimensions. CONCLUSION: Despite larger tumour dimensions, OBS is not inferior to WLE in providing clear surgical margins. Our analysis of the three-dimensional spatial relationship between cancer and surgical specimen, although not completely conclusive, can be helpful in the selection of the most appropriate surgical approach for every patient.


Assuntos
Neoplasias da Mama , Mastectomia Segmentar , Mama/diagnóstico por imagem , Mama/cirurgia , Neoplasias da Mama/cirurgia , Humanos , Margens de Excisão , Mastectomia
6.
J Surg Case Rep ; 2020(3): rjaa004, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32161635

RESUMO

Epidermoid inclusion cysts of the perineal region are a rare entity, which require appropriate diagnosis and management. Here we describe the unusual case of a large protruding epidermoid inclusion cyst originating from the intersphincteric anal plane, which was mobilized and excised successfully. Essential investigations to ensure accurate diagnosis in addition to surgical technique to reduce recurrence and patient morbidity are described in this case report.

7.
BMJ Case Rep ; 13(2)2020 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-32034000

RESUMO

Diaphragm disease (DD) of the small bowel is a rarely reported complication of non-steroidal anti-inflammatory drug (NSAID) use, characterised by diaphragm-like strictures, most commonly in the ileum, causing varying degrees of obstruction. It typically presents in the elderly, over many years with non-specific symptoms. Diagnosis is challenging, the majority of cases relying on histopathology for confirmation. Treatment involves NSAID cessation and surgery through a combination of stricturoplasties and/or segmental resection. Very rarely DD presents as a surgical emergency. A case presenting as acute small bowel obstruction (SBO) is described, initially diagnosed as adhesions, later confirmed to be DD of the terminal ileum following histopathological examination. Given the widespread use of NSAIDs and an ageing population, it is likely the incidence of DD will increase. It is, therefore, important that surgeons are aware of this disease entity and consider it as a potential diagnosis in patients presenting with acute SBO.


Assuntos
Anti-Inflamatórios não Esteroides/efeitos adversos , Obstrução Intestinal/etiologia , Intestino Delgado/patologia , Doença Aguda , Idoso , Constrição , Meios de Contraste , Feminino , Humanos , Intestino Delgado/diagnóstico por imagem , Aderências Teciduais , Tomografia Computadorizada por Raios X
8.
BMJ Case Rep ; 13(1)2020 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-31907219

RESUMO

Here we present a rare case of spontaneous colonic perforation in a middle-aged woman affected by systemic sclerosis (SSc). In spite of maximal medical support and prompt emergency laparotomy for source control the patient died due to multiorgan failure within 48 hours of admission. This case emphasises that although rarely, patients with scleroderma can present with colonic perforation which unfortunately due to their decreased physiological reserve, can lead to rapid and irreversible deterioration and subsequent death. It is therefore essential that clinicians faced with abdominal symptoms and signs in patients affected by SSc are able to quickly differentiate acute visceral perforation from benign causes.


Assuntos
Perfuração Intestinal/etiologia , Perfuração Intestinal/cirurgia , Escleroderma Sistêmico/complicações , Perfuração Espontânea/etiologia , Perfuração Espontânea/cirurgia , Evolução Fatal , Feminino , Humanos , Pessoa de Meia-Idade
9.
Lancet ; 393(10191): 2599-2612, 2019 06 29.
Artigo em Inglês | MEDLINE | ID: mdl-31178152

RESUMO

BACKGROUND: Adjuvant trastuzumab significantly improves outcomes for patients with HER2-positive early breast cancer. The standard treatment duration is 12 months but shorter treatment could provide similar efficacy while reducing toxicities and cost. We aimed to investigate whether 6-month adjuvant trastuzumab treatment is non-inferior to the standard 12-month treatment regarding disease-free survival. METHODS: This study is an open-label, randomised phase 3 non-inferiority trial. Patients were recruited from 152 centres in the UK. We randomly assigned patients with HER2-positive early breast cancer, aged 18 years or older, and with a clear indication for chemotherapy, by a computerised minimisation process (1:1), to receive either 6-month or 12-month trastuzumab delivered every 3 weeks intravenously (loading dose of 8 mg/kg followed by maintenance doses of 6 mg/kg) or subcutaneously (600 mg), given in combination with chemotherapy (concurrently or sequentially). The primary endpoint was disease-free survival, analysed by intention to treat, with a non-inferiority margin of 3% for 4-year disease-free survival. Safety was analysed in all patients who received trastuzumab. This trial is registered with EudraCT (number 2006-007018-39), ISRCTN (number 52968807), and ClinicalTrials.gov (number NCT00712140). FINDINGS: Between Oct 4, 2007, and July 31, 2015, 2045 patients were assigned to 12-month trastuzumab treatment and 2044 to 6-month treatment (one patient was excluded because they were double randomised). Median follow-up was 5·4 years (IQR 3·6-6·7) for both treatment groups, during which a disease-free survival event occurred in 265 (13%) of 2043 patients in the 6-month group and 247 (12%) of 2045 patients in the 12-month group. 4-year disease-free survival was 89·4% (95% CI 87·9-90·7) in the 6-month group and 89·8% (88·3-91·1) in the 12-month group (hazard ratio 1·07 [90% CI 0·93-1·24], non-inferiority p=0·011), showing non-inferiority of the 6-month treatment. 6-month trastuzumab treatment resulted in fewer patients reporting severe adverse events (373 [19%] of 1939 patients vs 459 [24%] of 1894 patients, p=0·0002) or stopping early because of cardiotoxicity (61 [3%] of 1939 patients vs 146 [8%] of 1894 patients, p<0·0001). INTERPRETATION: We have shown that 6-month trastuzumab treatment is non-inferior to 12-month treatment in patients with HER2-positive early breast cancer, with less cardiotoxicity and fewer severe adverse events. These results support consideration of reduced duration trastuzumab for women at similar risk of recurrence as to those included in the trial. FUNDING: UK National Institute for Health Research, Health Technology Assessment Programme.


Assuntos
Antineoplásicos Imunológicos/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Trastuzumab/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antineoplásicos Imunológicos/efeitos adversos , Neoplasias da Mama/metabolismo , Quimioterapia Adjuvante , Intervalo Livre de Doença , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Injeções Subcutâneas , Pessoa de Meia-Idade , Estudos Prospectivos , Receptor ErbB-2/metabolismo , Trastuzumab/efeitos adversos , Resultado do Tratamento , Reino Unido , Adulto Jovem
10.
Proc Natl Acad Sci U S A ; 116(17): 8380-8389, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30948643

RESUMO

The PIK3CA gene, which encodes the p110α catalytic subunit of PI3 kinase (PI3K), is mutationally activated in cancer and in overgrowth disorders known as PIK3CA-related overgrowth spectrum (PROS). To determine the consequences of genetic PIK3CA activation in a developmental context of relevance to both PROS and cancer, we engineered isogenic human induced pluripotent stem cells (iPSCs) with heterozygous or homozygous knockin of PIK3CAH1047R While heterozygous iPSCs remained largely similar to wild-type cells, homozygosity for PIK3CAH1047R caused widespread, cancer-like transcriptional remodeling, partial loss of epithelial morphology, up-regulation of stemness markers, and impaired differentiation to all three germ layers in vitro and in vivo. Genetic analysis of PIK3CA-associated cancers revealed that 64% had multiple oncogenic PIK3CA copies (39%) or additional PI3K signaling pathway-activating "hits" (25%). This contrasts with the prevailing view that PIK3CA mutations occur heterozygously in cancer. Our findings suggest that a PI3K activity threshold determines pathological consequences of oncogenic PIK3CA activation and provide insight into the specific role of this pathway in human pluripotent stem cells.


Assuntos
Classe I de Fosfatidilinositol 3-Quinases , Células-Tronco Pluripotentes Induzidas , Neoplasias , Adolescente , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases/genética , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Classe I de Fosfatidilinositol 3-Quinases/fisiologia , Feminino , Edição de Genes , Regulação Neoplásica da Expressão Gênica/genética , Técnicas de Introdução de Genes , Humanos , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/fisiologia , Masculino , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patologia , Transdução de Sinais/genética
13.
N Engl J Med ; 368(13): 1199-209, 2013 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-23484797

RESUMO

BACKGROUND: The management of metastatic breast cancer requires monitoring of the tumor burden to determine the response to treatment, and improved biomarkers are needed. Biomarkers such as cancer antigen 15-3 (CA 15-3) and circulating tumor cells have been widely studied. However, circulating cell-free DNA carrying tumor-specific alterations (circulating tumor DNA) has not been extensively investigated or compared with other circulating biomarkers in breast cancer. METHODS: We compared the radiographic imaging of tumors with the assay of circulating tumor DNA, CA 15-3, and circulating tumor cells in 30 women with metastatic breast cancer who were receiving systemic therapy. We used targeted or whole-genome sequencing to identify somatic genomic alterations and designed personalized assays to quantify circulating tumor DNA in serially collected plasma specimens. CA 15-3 levels and numbers of circulating tumor cells were measured at identical time points. RESULTS: Circulating tumor DNA was successfully detected in 29 of the 30 women (97%) in whom somatic genomic alterations were identified; CA 15-3 and circulating tumor cells were detected in 21 of 27 women (78%) and 26 of 30 women (87%), respectively. Circulating tumor DNA levels showed a greater dynamic range, and greater correlation with changes in tumor burden, than did CA 15-3 or circulating tumor cells. Among the measures tested, circulating tumor DNA provided the earliest measure of treatment response in 10 of 19 women (53%). CONCLUSIONS: This proof-of-concept analysis showed that circulating tumor DNA is an informative, inherently specific, and highly sensitive biomarker of metastatic breast cancer. (Funded by Cancer Research UK and others.).


Assuntos
Biomarcadores Tumorais/sangue , Neoplasias da Mama/secundário , DNA de Neoplasias/sangue , Mucina-1/sangue , Metástase Neoplásica/diagnóstico , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Feminino , Estudo de Associação Genômica Ampla , Humanos , Mutação , Metástase Neoplásica/diagnóstico por imagem , Metástase Neoplásica/genética , Prognóstico , Radiografia , Sensibilidade e Especificidade , Análise de Sequência de DNA/métodos , Carga Tumoral
15.
J Pathol ; 219(1): 131-40, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19562735

RESUMO

The pathogenesis of late normal tissue fibrosis after high-dose ionizing radiation involves multiple cell types and signalling pathways but is not well understood. To identify the molecular changes occurring after radiotherapy, paired normal tissue samples were collected from the non-irradiated breast and from the treated breast of women who had undergone curative radiotherapy for early breast cancer months or years previously. As radiation may induce distinct transcriptional changes in the different components of the breast, laser capture microdissection and gene expression microarray profiling were performed separately for epithelial and stromal components and selected genes were validated using immunohistochemistry. In the epithelial compartment, a reduction of KIT (c-Kit; CD117) and a reciprocal increase in ESR1 (oestrogen receptor-alpha, ERalpha) mRNA and protein levels were seen in irradiated compared to non-irradiated samples. In the stromal compartment, extracellular matrix genes including FN1 (fibronectin 1) and CTGF (connective tissue growth factor; CCN2) were increased. Further investigation revealed that c-Kit and ERalpha were expressed in distinct subpopulations of luminal epithelial cells. Interlobular c-Kit-positive mast cells were also increased in irradiated cases not showing features of post-radiation atrophy. Pathway analysis revealed 'cancer, reproductive system disease and tumour morphology' as the most significantly enriched network in the epithelial compartment, whereas in the stromal component, a significant enrichment for 'connective tissue disorders, dermatological diseases and conditions, genetic disorder' and 'cancer, tumour morphology, infection mechanism' networks was observed. These data identify previously unreported changes in the epithelial compartment and show altered expression of genes implicated in late normal tissue injury in the stromal compartment of normal breast tissue. The findings are relevant to both fibrosis and atrophy occurring after radiotherapy for early breast cancer.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/radioterapia , Mama/efeitos da radiação , Receptor alfa de Estrogênio/genética , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Proteínas Proto-Oncogênicas c-kit/genética , Adulto , Idoso , Mama/metabolismo , Neoplasias da Mama/patologia , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Células Epiteliais/efeitos da radiação , Receptor alfa de Estrogênio/análise , Feminino , Fibrose , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Estudo de Associação Genômica Ampla/métodos , Humanos , Imuno-Histoquímica , Microdissecção , Microscopia Confocal , Pessoa de Meia-Idade , Proteínas Proto-Oncogênicas c-kit/análise , Estatísticas não Paramétricas , Células Estromais/metabolismo , Células Estromais/patologia , Células Estromais/efeitos da radiação
16.
Clin Cancer Res ; 15(8): 2711-22, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19318498

RESUMO

PURPOSE: To characterize the molecular genetic profiles of grade 3 invasive ductal carcinomas of no special type using high-resolution microarray-based comparative genomic hybridization (aCGH) and to identify recurrent amplicons harboring putative therapeutic targets associated with luminal, HER-2, and basal-like tumor phenotypes. EXPERIMENTAL DESIGN: Ninety-five grade 3 invasive ductal carcinomas of no special type were classified into luminal, HER-2, and basal-like subgroups using a previously validated immunohistochemical panel. Tumor samples were microdissected and subjected to aCGH using a tiling path 32K BAC array platform. Selected regions of recurrent amplification were validated by means of in situ hybridization. Expression of genes pertaining to selected amplicons was investigated using quantitative real-time PCR and gene silencing was done using previously validated short hairpin RNA constructs. RESULTS: We show that basal-like and HER-2 tumors are characterized by "sawtooth" and "firestorm" genetic patterns, respectively, whereas luminal cancers were more heterogeneous. Apart from confirming known amplifications associated with basal-like (1q21, 10p, and 12p), luminal (8p12, 11q13, and 11q14), and HER-2 (17q12) cancers, we identified previously unreported recurrent amplifications associated with each molecular subgroup: 19q12 in basal-like, 1q32.1 in luminal, and 14q12 in HER-2 cancers. PPM1D gene amplification (17q23.2) was found in 20% and 8% of HER-2 and luminal cancers, respectively. Silencing of PPM1D by short hairpin RNA resulted in selective loss of viability in tumor cell lines harboring the 17q23.2 amplification. CONCLUSIONS: Our results show the power of aCGH analysis in unraveling the genetic profiles of specific subgroups of cancer and for the identification of novel therapeutic targets.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/genética , Carcinoma Ductal de Mama/patologia , Linhagem Celular Tumoral , Ciclina D1/genética , Receptor alfa de Estrogênio/genética , Amplificação de Genes/genética , Dosagem de Genes/genética , Perfilação da Expressão Gênica , Inativação Gênica , Genes erbB-1/genética , Genes erbB-2/genética , Humanos , Estadiamento de Neoplasias , Fosfoproteínas Fosfatases/genética , Proteína Fosfatase 2C
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