976 resultados para Tumor markers, biological
Resumo:
BACKGROUND: The single nucleotide polymorphism (SNP) rs2542151 within the gene locus region encoding protein tyrosine phosphatase non-receptor type 2 (PTPN2) has been associated with Crohn's disease (CD), ulcerative colitis (UC), type-I diabetes, and rheumatoid arthritis. We have previously shown that PTPN2 regulates mitogen-activated protein kinase (MAPK) signaling and cytokine secretion in human THP-1 monocytes and intestinal epithelial cells (IEC). Here, we studied whether intronic PTPN2 SNP rs1893217 regulates immune responses to the nucleotide-oligomerization domain 2 (NOD2) ligand, muramyl-dipeptide (MDP). MATERIALS AND METHODS: Genomic DNA samples from 343 CD and 663 non-IBD control patients (male and female) from a combined German, Swiss, and Polish cohort were genotyped for the presence of the PTPN2 SNPs, rs2542151, and rs1893217. PTPN2-variant rs1893217 was introduced into T(84) IEC or THP-1 cells using a lentiviral vector. RESULTS: We identified a novel association between the genetic variant, rs1893217, located in intron 7 of the PTPN2 gene and CD. Human THP-1 monocytes carrying this variant revealed increased MAPK activation as well as elevated mRNA expression of T-bet transcription factor and secretion of interferon-γ in response to the bacterial wall component, MDP. In contrast, secretion of interleukin-8 and tumor necrosis factor were reduced. In both, T(84) IEC and THP-1 monocytes, autophagosome formation was impaired. CONCLUSIONS: We identified a novel CD-associated PTPN2 variant that modulates innate immune responses to bacterial antigens. These findings not only provide key insights into the effects of a functional mutation on a clinically relevant gene, but also reveal how such a mutation could contribute to the onset of disease.
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Since 2004, four antiangiogenic drugs have been approved for clinical use in patients with advanced solid cancers, on the basis of their capacity to improve survival in phase III clinical studies. These achievements validated the concept introduced by Judah Folkman that the inhibition of tumor angiogenesis could control tumor growth. It has been suggested that biomarkers of angiogenesis would greatly facilitate the clinical development of antiangiogenic therapies. For these four drugs, the pharmacodynamic effects observed in early clinical studies were important to corroborate activities, but were not essential for the continuation of clinical development and approval. Furthermore, no validated biomarkers of angiogenesis or antiangiogenesis are available for routine clinical use. Thus, the quest for biomarkers of angiogenesis and their successful use in the development of antiangiogenic therapies are challenges in clinical oncology and translational cancer research. We review critical points resulting from the successful clinical trials, review current biomarkers, and discuss their potential impact on improving the clinical use of available antiangiogenic drugs and the development of new ones.
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The pathogenesis of hepatosplenic T-cell lymphoma (HSTL), a rare entity mostly derived from γδ T cells and usually with a fatal outcome, remains largely unknown. In this study, HSTL samples (7γδ and 2αβ) and the DERL2 HSTL cell line were subjected to combined gene-expression profiling and array-based comparative genomic hybridization. Compared with other T-cell lymphomas, HSTL had a distinct molecular signature irrespective of TCR cell lineage. Compared with peripheral T-cell lymphoma, not otherwise specified and normal γδ T cells, HSTL overexpressed genes encoding NK-cell-associated molecules, oncogenes (FOS and VAV3), the sphingosine-1-phosphatase receptor 5 involved in cell trafficking, and the tyrosine kinase SYK, whereas the tumor-suppressor gene AIM1 (absent in melanoma 1) was among the most down-expressed. We found highly methylated CpG islands of AIM1 in DERL2 cells, and decitabine treatment induced a significant increase in AIM1 transcripts. Syk was present in HSTL cells and DERL2 cells contained phosphorylated Syk and were sensitive to a Syk inhibitor in vitro. Genomic profiles confirmed recurrent isochromosome 7q (n = 6/9) without alterations at the SYK and AIM1 loci. Our results identify a distinct molecular signature for HSTL and highlight oncogenic pathways that offer rationale for exploring new therapeutic options such as Syk inhibitors and demethylating agents.
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Many biologically active peptides are protected from general proteolytic degradation by evolutionary conserved prolines (Pro), due to conformational constraints imposed by the Pro residue. Thus the biological importance of prolyl-specific peptidases points to a high potential for drug discovery for this family of enzymes. Panels of inhibitors have been synthesized and their effects, determined in biological models, suggest the inhibition of families of enzymes with similar activities. Prolyl-specific aminodipeptidases include dipeptidyl-aminodipeptidase IV (DPP IV)/CD26, DPP8, DPP9 and fibroblast activation protease-alpha (FAP-alpha)/seprase, able to release X-Pro dipeptides from the N-terminus of peptides. DPP IV inhibitors are in clinical use for type 2 diabetes. In this review, the expression and the potential functions of prolyl-aminodipeptidases are reviewed in diseases, and the inhibitors developed for these enzymes are discussed, with a specific focus on inhibitors able to discriminate between DPP IV and fibroblast activation protease-alpha (FAPalpha)/seprase as potential leads for the treatment of fibrogenic diseases.
Resumo:
PURPOSE: Prostate cancer is the most commonly diagnosed cancer in the United States. The diagnosis or followup of prostate cancer in men older than 50 years is based on digital rectal examination, measurement of the free-to-total prostatic specific antigen ratio and transrectal ultrasound assisted needle biopsy of the prostate. We developed and evaluated a noninvasive method for diagnosing prostate cancer based on the measurement of telomerase activity after prostatic massage in fresh voided urine or after urethral washing. MATERIALS AND METHODS: We obtained 36 specimens of cells after prostatic massage in the fresh voided urine of 16 patients who subsequently underwent radical prostatectomy and after urethral washing in 20 who underwent prostate needle biopsies. Ethylenediaminetetraacetic acid was immediately added to the collected urine or washing to a final concentration of 20 mM. After protein extraction by CHAPS buffer each specimen was tested for telomerase activity in a 2-step modified telomeric repeat amplification protocol assay. The 2 prostate cancer cell lines PC-3 and LNCaP with high telomerase activity were used as a positive control. RESULTS: Telomerase activity was detected in 14 of 24 samples with known prostate cancer (sensitivity 58%). In contrast, no telomerase activity was found in the 12 cases without histological evidence of prostate tumor (specificity 100%). Eight of 9 poorly differentiated cancers expressed telomerase activity (89%), while only 6 of 15 well and moderately differentiated cancers showed telomerase activity (40%). CONCLUSIONS: Our data illustrate that telomerase activity may be detected in voided urine or washing after prostatic massage in patients with prostate cancer. Sensitivity was higher for poorly differentiated tumors. This approach is not currently available for detecting prostate cancer in clinical practice. However, these results are promising and further studies are ongoing.
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PURPOSE: To improve the risk stratification of patients with rhabdomyosarcoma (RMS) through the use of clinical and molecular biologic data. PATIENTS AND METHODS: Two independent data sets of gene-expression profiling for 124 and 101 patients with RMS were used to derive prognostic gene signatures by using a meta-analysis. These and a previously published metagene signature were evaluated by using cross validation analyses. A combined clinical and molecular risk-stratification scheme that incorporated the PAX3/FOXO1 fusion gene status was derived from 287 patients with RMS and evaluated. RESULTS: We showed that our prognostic gene-expression signature and the one previously published performed well with reproducible and significant effects. However, their effect was reduced when cross validated or tested in independent data and did not add new prognostic information over the fusion gene status, which is simpler to assay. Among nonmetastatic patients, patients who were PAX3/FOXO1 positive had a significantly poorer outcome compared with both alveolar-negative and PAX7/FOXO1-positive patients. Furthermore, a new clinicomolecular risk score that incorporated fusion gene status (negative and PAX3/FOXO1 and PAX7/FOXO1 positive), Intergroup Rhabdomyosarcoma Study TNM stage, and age showed a significant increase in performance over the current risk-stratification scheme. CONCLUSION: Gene signatures can improve current stratification of patients with RMS but will require complex assays to be developed and extensive validation before clinical application. A significant majority of their prognostic value was encapsulated by the fusion gene status. A continuous risk score derived from the combination of clinical parameters with the presence or absence of PAX3/FOXO1 represents a robust approach to improving current risk-adapted therapy for RMS.
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Colorectal cancer is a clinical entity of a persistent relevance in clinical practice and its early diagnosis is a determinant factor to obtain better therapeutic results. Tumor markers are helpful means for a better approach to individuals with such neoplasm. In the present review, the authors analyze the phases in which surgical-clinical treatment markers must be used: diagnosis, determination of tumor stage, establishment of prognosis and detection of recurrence. Current and future markers and the consensus on their use are discussed. Causal factors for errors in diagnosis with markers and perspectives of use are also presented.
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The Barrett's esophagus (BE) is defined as endoscopically visible columnar mucosa at the distal esophagus, of any extension, proved to harbor intestinal metaplasia on biopsy, highlighted by the presence of goblet cells. BE denotes long-standing gastroesophageal reflux disease (GERD) and is an important risk factor for the development of esophageal adenocarcinoma (EAC). Therefore, these patients must be on follow-up, in order to diagnose cancer early. BE patients have frequent alterations in esophageal physiologyc studies. Alkaline duodenogastroesophageal reflux seems to have important role. The development BE occurs in steps, initially with formation of cardiac type mucosa subsequent intestinalization. Futher progression can follow a sequence, from low grade dysplasia, to high grade dysplasia and esophageal adenocarcinoma. Current follow-up is based on the presence of dysplasia. It has limitations, grouping patients heterogeneously. Different steps of carcinogenesis have been studied looking for an ideal prognostic marker. Uncontrolled proliferative activity, apoptosis inhibition, angiogenesis, tissue invasion and metastases formation are all implicated in cancer origin. Some cycle cell molecules have been studied in BE, such as retinoblastoma protein, ciclins, kinase dependent ciclins and cell cycle inhibitors. The P53 protein is one of the most investigated in the metaplasia-adenocarcinoma progression. Growth Factors, apoptotic proteins, telomers and DNA ploidy have also been searched. Increased proliferative activity has been implicated in Barrett's carcinogenesis and the Ki-67 antigen, through imunohistochemical analysis, has become the the method of choice. Present in the nucleus, it is found in proliferative cells only. Some studies suport association between Ki-67 activity and the metaplasia-dysplasia-adenocarcinoma sequence.The results, however, are inconclusive and research should follow this way.
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A primary carcinoid tumour of the breast in a 66-year-old man was diagnosed by fine-needle aspiration cytology. The nature of the lesion was proved by histochemical and immunocytochemical studies. The importance of a conclusive diagnosis is discussed and the value of immunocytochemical analysis as an aid to cytomorphologic diagnosis is demonstrated.
Simple mucin-type carbohydrate antigens (T, sialosyl T, Tn and sialosyl-Tn) in breast carcinogenesis
Resumo:
Immunohistochemical analysis of the expression of simple mucin-type carbohydrate antigens (Tn, sialyl-Tn and T) was performed in a series of 43 cases of intraductal hyperplasia without atypia, 9 cases of intraductal hyperplasia with atypia, 54 cases of ductal carcinoma in situ (DCIS) and 26 cases of invasive breast carcinoma. We also studied 36 cases of isolated breast normal epithelium, 20 cases of 'normal' breast epithelium adjacent to neoplasms and 14 cases of apocrine metaplasia. All antigens were detected in different frequencies in normal, hyperplastic, metaplastic and neoplastic breast epithelium. Tn and sialyl-Tn are expressed more frequently in malignant than in benign breast epithelium; while Tn expression increases from normal to invasive carcinomas, sialyl-Tn increases until DCIS and drops in invasive carcinomas, suggesting that either there is a failure of a proportion of DCIS to progress to invasive carcinoma or loss of expression of sialyl-Tn when some carcinomas become invasive. The high frequency of Tn and sialyl-Tn expression in breast intraductal proliferations probably reflects incomplete glycosylation in these lesions, which is a well-known tumour-associated phenomenon and supports the assumption that such lesions are putative precursors of breast cancer. T antigen was expressed in all groups studied, but its prevalence differed significantly between normal and neoplastic epithelium. The expression of these antigens in epithelium adjacent to carcinomas is similar to that found in isolated normal breast epithelium, whereas apocrine metaplasia has a pattern of simple mucin-type glycosylation that is specific and distinct from that of the normal breast epithelium, with a high frequency of marked expression of Tn and sialyl-Tn. The similarity of the pattern of expression of simple mucin-type antigens in metaplasia and malignant neoplasia reduces the usefulness of these markers from a diagnostic standpoint.
Resumo:
OBJECTIVE: To investigate the usefulness of assessing the immunoreactivity of cytokeratins 7 (CK7) and 20 (CK20) as well as several cytomorphologic parameters in effusions with metastatic adenocarcinomas in the search for the primary site of the tumor. STUDY DESIGN: From the files of the Pathology Department, A. C. Camargo Hospital, we studied cytologic smears from 73 metastatic adenocarcinomas originally from the breast, 63 from the ovary, 40 from the lung and 32 from the stomach, looking for morphologic parameters that could have discriminant potential in suggesting the primary site in a routine situation, including intranuclear inclusions, prominent nucleoli, mitosis, signet-ring cells, psammoma bodies, nuclear crease, binucleation and multinucleation, papillary features, acinar profile (including ball cells) and single cells. Immunoreactions were performed with monoclonal antibodies to CK7 (OV-TL 12/30 and CK20 (Ks 20.8) and included morphologic analysis. Both analyses were studied in a blind fashion regarding the primary site of the tumors. RESULTS: Positivity ratios for breast, ovary, stomach and lung cases were 67.6%, 63.5%, 29.7% and 45.5%, respectively, for CK7 and 17.2%, 15.8%, 13.5% and 32.2%, respectively, for CK20. Discriminant analysis of morphologic and immunocytochemical parameters had an error rate of 42.9% in recognizing the primary site and a Wilk's lambda of .7290. CONCLUSION: The more efficient parameter with discriminant function was the papillary appearance showed by CK7, which should be used in further studies with a similar scope. The set of parameters used in this study were insufficient to discriminate the primary site of female adenocarcinomas in effusions with significant accuracy.
Resumo:
We analyzed clinicopathologic data, immunophenotype, and Epstein-Barr virus (EBV) status in 96 cases of Hodgkin disease (HD) in juveniles (younger than 20 years) and adults (20 years or older) from 2 distinctive states in Brazil. We studied 34 juvenile (group 1) and 16 adult (group 2) cases from Ceara and 31 juvenile (group 3) and 15 adult (group 4) cases from São Paulo. Ceara has a socioeconomic profile similar to a developing country; São Paulo is in better economic condition. Mixed cellularity (MC) was the major histologic subtype among groups 1 (22 [65%]), 3 (21 [68%]), and 4 (7 [47%]); nodular sclerosis (NS) was more frequent in group 2 (8 [50%]). EBV infection was observed in 61 cases (64%), including the following (among others): group 1, MC, 22 (65%) and NS, 4 (12%); group 2, NS, 3 (19%) and MC, 2 (12%); group 3, MC, 16 (52%) and NS, 1 (3%); and group 4, MC, 7 (47%). There was predominance of EBV+ HD cases in group 1 compared with group 3. HD in Brazilian patients is highly associated with EBV infection, but geographic differences reflect histologic subtypes and age distribution.