950 resultados para HUMAN GASTRIC-CANCER
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Penile cancer is a potentially mutilating disease. Although its occurrence is relatively rare worldwide, penile cancer rates can be high in developing countries. A few studies have been conducted on the involvement of human papillomavirus (HPV) in penile carcinoma, which have found HPV present in 30-70% of penile malignant lesions, with a higher prevalence of HPV 16 and 18. It has been assumed that cofactors, such as Epstein-Barr virus (EBV) infections, may play a role in the progression of penile neoplasia. The aim of this study was to determine HPV and EBV prevalence in 135 penile malignant lesions from Brazilian men through the use of MY09/11 polymerase chain reaction (PCR), type-specific PCR and restriction fragment length polymorphism analysis. HPV prevalence among the men tested was 60.7%. Of the men who tested positive, 27 presented with HPV 16 (29.7%), five with HPV 18 (5.5%), 21 with HPV 45 (23.1%) and nine with HPV 6 (9.9%). Seven mixed infections were detected (9.2%), while 11 cases remained untyped (13.4%). Regarding EBV positivity, 46.7% of the samples contained EBV DNA with EBV-1 as the most prevalent type (74.6%). More than 23% of the men were co-infected with both HPV and EBV, while 35% presented exclusively with HPV DNA and 20% presented only with EBV DNA. Penile carcinoma aetiology has not been fully elucidated and the role of HPV and EBV infections individually or synergistically is still controversial. Hence, more studies are needed to determine their possible role in carcinogenesis.
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BACKGROUND Human papillomavirus (HPV)-related head and neck cancer has been associated with an improved prognosis in patients treated with radiotherapy (RT) +/- chemotherapy (CT); however, RT combined with epidermal growth factor receptor (EGFR) inhibitors has not been fully studied in this group of patients. METHODS Immunohistochemical expression of p16 and PCR of HPV16 DNA were retrospectively analyzed in tumor blocks from 108 stage III/IV head and neck cancer patients treated with RT+CT (56) or RT+EGFR inhibitors (52). Disease-free survival (DFS) and overall survival (OS) were analyzed by the Kaplan-Meier method. RESULTS DNA of HPV16 was found in 12 of 108 tumors (11%) and p16 positivity in 18 tumors (17%), with similar rates in both arms of treatment. After a median follow-up time of 35 months (range 6-135), p16-positive patients treated with RT+EGFR inhibitors showed improved survival compared with those treated with RT+CT (2-year OS 88% vs. 60%, HR 0.18; 95% CI 0.04 to 0.88; p = 0.01; and 2-year DFS 75% vs. 47%, HR 0.17; 95% CI 0.03 to 0.8; p = 0.01). However, no differences were observed in p16-negative patients (2-year OS 56% vs. 53%, HR 0.97; 95% CI 0.55 to 1.7; p = 0.9; and 2-year DFS 43% vs. 45%, HR 0.99; 95% CI 0.57 to 1.7; p = 0.9). CONCLUSIONS This is the first study to show that p16-positive patients may benefit more from RT+EGFR inhibitors than conventional RT+CT. These results are hypothesis-generating and should be confirmed in prospective trials.
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BACKGROUND AND OBJECTIVES Cancer testis antigens (CTA) provide attractive targets for cancer-specific immunotherapy. Although CTA genes are expressed in some normal tissues, such as the testis, this immunologically protected site lacks MHC I expression and as such, does not present self antigens to T cells. To date, CTA genes have been shown to be expressed in a range of solid tumors via demethylation of their promoter CpG islands, but rarely in chronic myeloid leukemia (CML) or other hematologic malignancies. DESIGN AND METHODS In this study, the methylation status of the HAGE CTA gene promoter was analyzed by quantitative methylation-specific polymerase chain reaction (MSP) and sequencing in four Philadelphia-positive cell lines (TCC-S, K562, KU812 and KYO-1) and in CML samples taken from patients in chronic phase (CP n=215) or blast crisis (BC n=47). HAGE expression was assessed by quantitative reverse transcriptase-polymerase chain reaction. RESULTS The TCC-S cell line showed demethylation of HAGE that was associated with over-expression of this gene. HAGE hypomethylation was significantly more frequent in BC (46%) than in CP (22%) (p=0.01) and was correlated with high expression levels of HAGE transcripts (p<0.0001). Of note, in CP-CML, extensive HAGE hypomethylation was associated with poorer prognosis in terms of cytogenetic response to interferon (p=0.01) or imatinib (p=0.01), molecular response to imatinib (p=0.003) and progression-free survival (p=0.05). INTERPRETATIONS AND CONCLUSION: The methylation status of the HAGE promoter directly correlates with its expression in both CML cell lines and patients and is associated with advanced disease and poor outcome.
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Transcriptional deregulation in cancer has been shown to be associated with epigenetic alterations, in particular to tumor-suppressor- gene (TSG) promoters. In contrast, DNA methylation of TSGs is not considered to be present in normal differentiated cells. Nevertheless, we previously showed that the promoter of the tumor-suppressor gene APC is methylated, for one allele only, in normal gastric cells. Recently, RASSF1A has been shown to be imprinted in normal human placenta. To clarify putative TSG methylation in the placenta, 23 normal placental tissues from the first trimester, both decidua and villi, and four normal non-gestational endometrium were screened for DNA methylation by methylation-sensitive single-strand conformation analysis (MS-SSCA) and sequencing after bisulfite modification, on a panel of 12 genes known to be implicated in carcinogenesis. In all placental villi, four TSG promoters-APC, SFRP2, RASSF1A and WIF1-were hypermethylated, whereas all decidua and normal endometrium did not show any methylation. Allele-specific methylation analysis revealed that this methylation was monoallelic. Furthermore, comparison with maternal DNA indicated that APC and WIF1 were methylated on the maternal allele, whereas SFRP2 was methylated on the paternal allele. Sequence analysis of WIF1 mRNA revealed that only the unmethylated paternal allele was transcribed. The imprinting status of these TSGs is conserved during pregnancy. These results indicate that TSG imprinting is pre-existent in normal human placenta and should not be confused with carcinogenesis or pathology-induced methylation.
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RESUME Le cancer du col de l'utérus, deuxième cause de mort par cancer chez la femme, a pu être associé à une infection par plusieurs types de virus du Papillome Humain (HPV), et en particulier HPV 16. Les vaccins prophylactiques sont efficaces à prévenir le cancer du col utérin alors que les lésions de haut grade sont généralement traitées par ablation chirurgicale et par d'éventuels traitements additionnels. Les risques de récurrence liés aux ablations et le taux de mortalité (50%) lié au cancer, démontrent le besoin de développer des stratégies alternatives afin de cibler les lésions précancéreuses. A ce jour, les vaccins thérapeutiques ont démontré peu de résultats cliniques, contrastant avec les régressions de tumeurs ectopiques observées après vaccination dans des modèles murins avec tumeurs associées à HPV. L'induction de réponses immunitaires protectrices dans la muqueuse génitale semble être cruciale pour l'efficacité des vaccins thérapeutiques HPV et évaluer leur efficacité dans un modèle murin avec tumeurs-HPV génitales représente un pré-requis important avant de procéder à des études cliniques. Par conséquent, nous avons établi un modèle murin orthotopique où des tumeurs se développent dans (a muqueuse génitale après une instillation intra-vaginale (i.vag) de cellules tumorales exprimant les oncogènes E6/E7 d'HPV 16 et transduites par un vecteur lentiviral codant la luciferase afin de suivre le développement de ces tumeurs in vivo par imagerie. La caractérisation histologique a démontré que les tumeurs grandissaient dans l'épithélium vaginal et en accord avec leur localisation, des cellules Τ CD8 spécifiques à E7 induites par la tumeur n'étaient détectées que dans la muqueuse génitale et les ganglions drainants. Une infiltration de cellules Τ régulatrices a aussi été mise en évidence, empêchant la régression spontanée de ces tumeurs. Par conséquent, ce modèle devrait être plus adéquat pour tester des stratégies thérapeutiques, étant donné qu'il partage certaines similarités immunologiques avec les lésions génitales naturelles causées par HPV. Etant donné que les oncogènes E6 et E7 d'HPV sont nécessaires à la maintenance du phénotype cancéreux des cellules cervicales, elles représentent des antigènes cibles pour la vaccination thérapeutique. Nous avons démontré que des souris immunisées par voie sous-cutanée (s.c.) avec une dose d'un vaccin à base de polypeptide E7 d'HPV 16 et d'adjuvants, présentaient de nombreuses cellules Τ CD8 sécrétant de l'IFN-γ spécifiquement à E7 dans leurs organes lymphatiques mais également dans la muqueuse génitale. De plus, le manque de corrélation entre les réponses spécifiques mesurées dans la périphérie et dans la muqueuse génitale souligne la nécessité et l'importance de déterminer les réponses immunitaires localement là où les lésions dues à HPV se développent. Si une vaccination par voie muqueuse est plus propice à traiter/régresser des infections génitales/tumeurs que le voie parentérale est un sujet débattu. Nos données montrent que seule la voie s.c. était capable de régresser la quasi totalité des tumeurs génitales chez la souris bien que des réponses CD8 spécifiques à E7 similaires étaient mesurées dans la muqueuse génitale après des vaccinations intra-nasale et i.vag. Afin d'augmenter la réponse spécifique au vaccin dans la muqueuse génitale, des immunostimulants ont été administrés par voie i.vag après vaccination. Nous avons démontré qu'une application i.vag d'agonistes des Toll like receptors après une vaccination s.c. induisait de manière significative une augmentation des cellules Τ CD8 sécrétant de l'IFN-γ spécifiquement à E7 dans la muqueuse génitale. Plus précisément et concernant les CpG et Poly l:C, l'effet était probablement associé à une attraction locale des cellules Τ CD8 et deuxièmement dépendait respectivement des voies de signalisation TLR9 et TLR3/Mda5. Finalement, cette stratégie combinatoire a permis de régresser des grosses tumeurs génitales chez la souris, suggérant qu'une telle immunothérapie pourrait adéquatement traiter des lésions dues à HPV chez les femmes. SUMMARY Cervical cancer is the second leading cause of cancer mortality in women worldwide and results from an infection with a subset of Human Papillomavirus (HPV), HPV 16 representing the most prevalent type. The available prophylactic vaccines are an effective strategy to prevent cervical cancer while already established high grade lesions usually require surgical ablation of lesion with possible additional treatments. Recurrence risks linked to conventional ablations and the high mortality (50%) related to cervical cancer demonstrate the need for alternative strategies like immunotherapies to target pre¬cancerous lesions. Until now, therapeutic vaccines only showed limited clinical results, which strongly contrast with the regression of ectopic tumors observed in the available murine HPV tumor models after vaccination. Induction of protective immune responses in the genital mucosa (GM) may be crucial for efficacy of HPV therapeutic vaccines and evaluating their efficacy in a murine model with genital HPV- tumors represents an important prerequisite for clinical trials. Thus, we have here established an orthotopic mouse model where tumors in the GM develop after an intravaginal (i.vag) instillation of HPV 16 E6/E7 oncogenes-expressing tumor cells transduced with a luciferase encoding lentivirus vector for in vivo imaging of tumor growth. Histological characterization showed that tumor grew within the vaginal epithelium and according to their mucosal location tumor- induced E7-specific CD8 Τ cells were restricted to the GM and genital draining lymph nodes together with high Τ regulatory cells infiltrates preventing spontaneous regression. Consequently, sharing several immunological similarities with natural genital HPV lesions, this novel genital tumor model may be more adequate to test therapeutic strategies. As E6 and/or E7 HPV oncogenes expression is required for the maintenance of the cancerous phenotype of cervical cells, they represent target antigens for therapeutic vaccination. We reported that mice subcutaneously (s.c.) immunized once with an adjuvanted HPV 16 E7 polypeptide vaccine harbored high E7-specific IFN-γ secreting CD8 Τ cells in their lymphoid organs and more importantly in the GM. In addition, the lack of correlation between specific responses measured in the periphery with those measured in the GM highlighted the necessity and relevance to determine the immune responses locally where HPV 16-induced lesions develop. Whether a mucosal route of immunization is better to treat/regress genital infections/tumors than parenteral immunization is still debated. Our data shows that although similar E7-specific IFN-γ secreting CD8 Τ cells responses were measured in the GM upon mucosal routes of E7 vaccine delivery (nasal and vaginal immunizations), only the s.c immunization was able to regress at least all genital tumors in mice. To further increase the vaccine-specific responses in the GM, immunostimulatory agents were i.vag administrated after vaccination. We demonstrated that a single i.vag application of toll like receptor (TLR) agonists after a s.c. E7 vaccination induced a significant increase of E7-specific IFN-γ secreting CD8 Τ cells in the GM. More precisely, regarding CpG and Poly l:C, the effect is most probably associated with a local attraction of total CD8 Τ cells and secondly depends on TLR9 and TLR3/Mda5 signaling pathways, respectively. Finally, this combinatorial strategy induced tumor regression in mice harboring large genital tumors, suggesting that such an immunotherapy could be adequate to treat HPV-induced lesions in women.
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A considerable public concern about cancer risk from acrylamide-rich foods followed the announcement that high concentrations of acrylamide are found in fried potatoes and potato chips and, more generally, in starch-containing foods cooked at high temperatures. From a series of hospital-based case-control studies conducted in Italy and Switzerland between 1991 and 2000, we have analyzed the relation between intake of fried/baked potatoes and cancer risk. The cancer sites considered were oral cavity and pharynx (749 cases, 1772 controls), esophagus (395 cases, 1066 controls), larynx (527 cases, 1297 controls), large bowel (1225 colon and 728 rectum cases, 4154 controls), breast (2569 cases, 2588 controls) and ovary (1031 cases, 2411 controls). All cancer cases were incident and histologically confirmed. Controls were subjects admitted to the same network of hospitals of cases for acute, non-neoplastic conditions. All the odds ratios (OR) for the highest vs. the lowest tertile of intake ranged between 0.8-1.1. We found no evidence of interaction with age, gender, alcohol and tobacco use. Our data provide reassuring evidence for the lack of an important association between consumption of fried/baked potatoes and cancer risk.
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Background: Two genes are called synthetic lethal (SL) if mutation of either alone is not lethal, but mutation of both leads to death or a significant decrease in organism's fitness. The detection of SL gene pairs constitutes a promising alternative for anti-cancer therapy. As cancer cells exhibit a large number of mutations, the identification of these mutated genes' SL partners may provide specific anti-cancer drug candidates, with minor perturbations to the healthy cells. Since existent SL data is mainly restricted to yeast screenings, the road towards human SL candidates is limited to inference methods. Results: In the present work, we use phylogenetic analysis and database manipulation (BioGRID for interactions, Ensembl and NCBI for homology, Gene Ontology for GO attributes) in order to reconstruct the phylogenetically-inferred SL gene network for human. In addition, available data on cancer mutated genes (COSMIC and Cancer Gene Census databases) as well as on existent approved drugs (DrugBank database) supports our selection of cancer-therapy candidates.Conclusions: Our work provides a complementary alternative to the current methods for drug discovering and gene target identification in anti-cancer research. Novel SL screening analysis and the use of highly curated databases would contribute to improve the results of this methodology.
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Background: Cancer is a major medical problem in modern societies. However, the incidence of this disease in non-human primates is very low. To study whether genetic differences between human and chimpanzee could contribute to their distinct cancer susceptibility, we have examined in the chimpanzee genome the orthologous genes of a set of 333 human cancer genes. Results: This analysis has revealed that all examined human cancer genes are present in chimpanzee, contain intact open reading frames and show a high degree of conservation between both species. However, detailed analysis of this set of genes has shown some differences in genes of special relevance for human cancer. Thus, the chimpanzee gene encoding p53 contains a Pro residue at codon 72, while this codon is polymorphic in humans and can code for Arg or Pro, generating isoforms with different ability to induce apoptosis or interact with p73. Moreover, sequencing of the BRCA1 gene has shown an 8 Kb deletion in the chimpanzee sequence that prematurely truncates the co-regulated NBR2 gene. Conclusion: These data suggest that small differences in cancer genes, as those found in tumor suppressor genes, might influence the differences in cancer susceptibility between human and chimpanzee. Nevertheless, further analysis will be required to determine the exact contribution of the genetic changes identified in this study to the different cancer incidence in non-human primates.
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Background: One of the main goals of cancer genetics is to identify the causative elements at the molecular level leading to cancer.Results: We have conducted an analysis of a set of genes known to be involved in cancer in order to unveil their unique features that can assist towards the identification of new candidate cancer genes. Conclusion: We have detected key patterns in this group of genes in terms of the molecular function or the biological process in which they are involved as well as sequence properties. Based on these features we have developed an accurate Bayesian classification model with which human genes have been scored for their likelihood of involvement in cancer.
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Le cancer est défini comme la croissance incontrôlée des cellules dans le corps. Il est responsable de 20 % des décès en Europe. Plusieurs expériences montrent que les tumeurs sont issues et se développent grâce à un petit nombre de cellules, que l'on appelle cellules souches cancéreuses (CSC). Ces CSC sont également responsables de l'apparition de métastases et de la résistance aux médicaments anticancéreux. De ce fait, l'identification des gènes qui contribuent aux propriétés de ces CSC (comme la survie des tumeurs, les métastases et la résistance aux médicaments) est nécessaire pour mieux comprendre la biologie des cancers et d'améliorer la qualité des soins des patients avec un cancer. A ce jour, de nombreux marqueurs ont été proposés ainsi que de nouvelles thérapies ciblées contre les CSC. Toutefois, et malgré les énormes efforts de la recherche dans ce domaine, la quasi-totalité des marqueurs de CSC connus à ce jour sont aussi exprimés dans les cellules saines. Ce projet de recherche visait à trouver un nouveau candidat spécifique des CSC. Le gène BORIS (pour Brother of Regulator of Imprinted Sites), nommé aussi CTCFL (CTCF-like), semble avoir certaines caractéristiques de CSC et pourrait donc devenir une cible prometteuse pour le traitement du cancer. BORIS/CTCFL est une protéine nucléaire qui se lie à l'ADN, qui est exprimée dans les tissus normaux uniquement dans les cellules germinales et qui est réactivée dans un grand nombre de tumeurs. BORIS est impliqué dans la reprogrammation épigénétique au cours du développement et dans la tumorigenèse. En outre, des études récentes ont montré une association entre l'expression de BORIS et un mauvais pronostic chez des patients atteints de différents types de cancers. Nous avons développé une nouvelle technologie basée sur les Molecular Beacon pour cibler l'ARNm de BORIS et cela dans les cellules vivantes. Grâce à ce système expérimental, nous avons montré que seule une toute petite sous-population (0,02 à 5%) de cellules tumorales exprimait fortement BORIS. Les cellules exprimant BORIS ont pu être isolées et elles présentaient les caractéristiques de CSC, telles qu'une forte expression de hTERT et des gènes spécifiques des cellules souches (NANOG, SOX2 et OCT4). En outre, une expression élevée de BORIS a été mise en évidence dans des populations enrichies en CSC ('side population' et sphères). Ces résultats suggèrent que BORIS pourrait devenir un nouveau et important marqueur de CSC. Dans des études fonctionnelles sur des cellules de cancer du côlon et du sein, nous avons montré que le blocage de l'expression de BORIS altère largement la capacité de ces cellules à former des sphères, démontrant ainsi un rôle essentiel de BORIS dans l'auto- renouvellement des tumeurs. Nos expériences montrent aussi que BORIS est un facteur important qui régule l'expression de gènes jouant un rôle clé dans le développement et la progression tumorale, tels le gène hTERT et ceux impliqués dans les cellules souches, les CSC et la transition épithélio-mésenchymateuse (EMT). BORIS pourrait affecter la régulation de la transcription de ces gènes par des modifications épigénétiques et de manière différente en fonction du type cellulaire. En résumé, nos résultats fournissent la preuve que BORIS peut être classé comme un gène marqueur de cellules souches cancéreuse et révèlent un nouveau mécanisme dans lequel BORIS jouerait un rôle important dans la carcinogénèse. Cette étude ouvre de nouvelles voies pour mieux comprendre la biologie de la progression tumorale et offre la possibilité de développement de nouvelles thérapies anti-tumorales et anti-CSC avec BORIS comme molécule cible. - Cancer is defined as the uncontrolled growth of cells in the body. It causes 20% of deaths in the European region. Current evidences suggest that tumors originate and are maintained thanks to a small subset of cells, named cancer stems cells (CSCs). These CSCs are also responsible for the appearance of metastasis and therapeutic resistance. Consequently, the identification of genes that contribute to the CSC properties (tumor survival, metastasis and therapeutic resistance) is necessary to better understand the biology of malignant diseases and to improve care management. To date, numerous markers have been proposed to use as new CSC- targeted therapies. Despite the enormous efforts in research, almost all of the known CSCs markers are also expressed in normal cells. This project aimed to find a new CSC-specific candidate. BORIS (Brother of Regulator of Imprinted Sites) or CTCFL (CTCF-like) is a DNA binding protein involves in epigenetic reprogramming in normal development and in tumorigenesis. Recent studies have shown an association of BORIS expression with a poor prognosis in different types of cancer patients. Therefore, BORIS seems to have the same characteristics of CSCs markers and it could be a promising target for cancer therapy. BORIS is normally expressed only in germinal cells and it is re-expressed in a wide variety of tumors. We developed a new molecular beacon-based technology to target BORIS mRNA expressing cells. Using this system, we showed that the BORIS expressing cells are only a small subpopulation (0.02-5%) of tumor cells. The isolated BORIS expressing cells exhibited the characteristics of CSCs, with high expression of hTERT and stem cell genes (NANOG, SOX2 and OCT4). Furthermore, high BORIS expression was observed in the CSC-enriched populations (side population and spheres). These results suggest that BORIS might be a novel and powerful CSCs marker. In functional studies, we observed that BORIS knockdown significantly impairs the capacity to form spheres in colon and breast cancer cells, thus demonstrating a critical role of BORIS in the self-renewal of tumors. The results showed in the functional analysis indicate that BORIS is an important factor that regulates the expression of key-target genes for tumor development and progression, such as hTERT, stem cells, CSCs markers and EMT (epithelial mesenchymal transition)-related marker genes. BORIS could affect the transcriptional regulation of these genes by epigenetic modification and in a cell type dependent manner. In summary, our results support the evidence that BORIS can be classified as a cancer stem cell marker gene and reveal a novel mechanism in which BORIS would play a critical role in tumorigenesis. This study opens new prospective to understand the biology of tumor development and provides opportunities for potential anti-tumor drugs.
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Recombinant human tumour necrosis factor (TNF) has a selective effect on angiogenic vessels in tumours. Given that it induces vasoplegia, its clinical use has been limited to administration through isolated limb perfusion (ILP) for regionally advanced melanomas and soft tissue sarcomas of the limbs. When combined with the alkylating agent melphalan, a single ILP produces a very high objective response rate. In melanoma, the complete response (CR) rate is around 80% and the overall objective response rate greater than 90%. In soft tissue sarcomas that are inextirpable, ILP is a neoadjuvant treatment resulting in limb salvage in 80% of the cases. The CR rate averages 20% and the objective response rate is around 80%. The mode of action of TNF-based ILP involves two distinct and successive effects on the tumour-associated vasculature: first, an increase in endothelium permeability leading to improved chemotherapy penetration within the tumour tissue, and second, a selective killing of angiogenic endothelial cells resulting in tumour vessel destruction. The mechanism whereby these events occur involves rapid (of the order of minutes) perturbation of cell-cell adhesive junctions and inhibition of alphavbeta3 integrin signalling in tumour-associated vessels, followed by massive death of endothelial cells and tumour vascular collapse 24 hours later. New, promising approaches for the systemic use of TNF in cancer therapy include TNF targeting by means of single chain antibodies or endothelial cell ligands, or combined administration with drugs perturbing integrin-dependent signalling and sensitizing angiogenic endothelial cells to TNF-induced death.
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Cancer/testis (CT) genes are normally expressed in germ cells only, yet are reactivated and expressed in some tumors. Of the approximately 40 CT genes or gene families identified to date, 20 are on the X chromosome and are present as multigene families, many with highly conserved members. This indicates that novel CT gene families may be identified by detecting duplicated expressed genes on chromosome X. By searching for transcript clusters that map to multiple locations on the chromosome, followed by in silico analysis of their gene expression profiles, we identified five novel gene families with testis-specific expression and >98% sequence identity among family members. The expression of these genes in normal tissues and various tumor cell lines and specimens was evaluated by qualitative and quantitative RT-PCR, and a novel CT gene family with at least 13 copies was identified on Xq24, designated as CT47. mRNA expression of CT47 was found mainly in the testes, with weak expression in the placenta. Brain tissue was the only positive somatic tissue tested, with an estimated CT47 transcript level 0.09% of that found in testis. Among the tumor specimens tested, CT47 expression was found in approximately 15% of lung cancer and esophageal cancer specimens, but not in colorectal cancer or breast cancer. The putative CT47 protein consists of 288 amino acid residues, with a C-terminus rich in alanine and glutamic acid. The only species other than human in which a gene homologous to CT47 has been detected is the chimpanzee, with the predicted protein showing approximately 80% identity in its carboxy terminal region.
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BACKGROUND: Lapatinib is an effective anti-HER2 therapy in advanced breast cancer and docetaxel is one of the most active agents in breast cancer. Combining these agents in pre-treated patients with metastatic disease had previously proved challenging, so the primary objective of this study aimed to determine the maximum tolerated dose (MTD) in treatment-naive patients, by identifying acute dose-limiting toxicities (DLT) during cycle 1 in the first part of a phases 1-2 neoadjuvant European Organisation for Research and Treatment of Cancer (EORTC) trial. PATIENTS AND METHODS: Patients with large operable or locally-advanced HER2 positive breast cancer were treated with continuous lapatinib, and docetaxel every 21days for 4 cycles. Dose levels (DLs) were: 1000/75, 1250/75, 1000/85, 1250/85, 1000/100 and 1250/100 (mg/day)/(mg/m(2)). RESULTS: Twenty-one patients were included. Two DLTs occurred at dose level 5 (1000/100); one grade 4 neutropenia ⩾7days and one febrile neutropenia. A further 3 patients were therefore treated at the same dose with prophylactic granulocyte-colony stimulating factor (G-CSF), and 3 patients at dose level 6. No further DLTs were observed. CONCLUSIONS: Our recommended dose for phase II is lapatinib 1000mg/day and docetaxel 100mg/m(2) with G-CSF in HER2 positive non-metastatic breast cancer. The dose of lapatinib should have been 1250mg/day but we were mindful of the high rate of treatment discontinuation in GeparQuinto with lapatinib 1250mg/day combined with docetaxel. No grade 3-4 diarrhoea was observed. Pharmacodynamics analysis suggests that concomitant medications altering P-glycoprotein activity (in addition to lapatinib) can modify toxicity, including non-haematological toxicities. This needs verification in larger trials, where it may contribute to understanding the sources of variability in clinical toxicity and treatment discontinuation.
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Full-term pregnancies are associated with long-term reductions in maternal risk of breast cancer, but the biological determinants of the protection are unknown. Experimental observations suggest that human chorionic gonadotropin (hCG), a major hormone of pregnancy, could play a role in this association. A case-control study (242 cases and 450 controls) nested within the Northern Sweden Maternity Cohort included women who had donated a blood sample during the first trimester of a first full-term pregnancy. Total hCG was determined on Immulite 2000 analyzer. Odds ratios (OR) and 95% confidence intervals (CI) were estimated through conditional logistic regression. Maternal breast cancer risk decreased with increasing hCG (upper tertile OR, 0.67; CI, 0.46-0.99), especially for pregnancies before age 25 (upper tertile OR, 0.41; CI, 0.21-0.80). The association diverged according to age at diagnosis: risk was reduced after age 40 (upper tertile OR, 0.60; CI, 0.39-0.91) and seemed to increase before age 40 (upper tertile OR, 1.78; CI, 0.72-4.38). Risk was reduced among those diagnosed 10 years or longer after blood draw (upper tertile OR, 0.60; CI, 0.40-0.90), but not so among those diagnosed within 10 years (upper tertile OR, 4.33; CI, 0.86-21.7). These observations suggest that the association between pregnancy hCG and subsequent maternal risk of breast cancer is modified by age at diagnosis. Although the hormone seems to be a determinant of the reduced risk around or after age 50, it might not confer protection against, or it could even increase the risk of, cancers diagnosed in the years immediately following pregnancy.
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BACKGROUND: We investigated whether the free β-human chorionic gonadotropin (free β-hCG) would provide additional information to that provided by total hCG alone and thus be useful in future epidemiological studies relating hCG to maternal breast cancer risk. MATERIALS & METHODS: Cases (n = 159) and controls (n = 286) were a subset of our previous study within the Northern Sweden Maternity Cohort on total hCG during primiparous pregnancy and breast cancer risk. RESULTS: The associations between total hCG (hazard ratio: 0.79; 95% CI: 0.49-1.27), free β-hCG (hazard ratio: 0.85; 95% CI: 0.33-2.18) and maternal risk of breast cancer were very similar in all analyses and mutual adjustment for either one had minor effects on the risk estimates. CONCLUSION: In the absence of a reliable assay on intact hCG, total hCG alone can be used in epidemiological studies investigating hCG and breast cancer risk, as free β-hCG does not appear to provide any additional information.