Search results for "p53"
showing 10 items of 303 documents
Clinicopathological and immunohistochemical analysis of 20 cases of Merkel cell carcinoma in search of prognostic markers.
2005
Aims: To evaluate the clinicopathological and immunohistochemical characteristics of Merkel cell carcinoma (MCC) in an attempt to find new, potentially significant, prognostic markers. Methods and results: Clinical data and follow-up, histopathological features (pattern, cell size, thickness, mitoses, vascular invasion, lymphocytic infiltration) and immunohistochemical detection [CK20, thyroid transcription factor (TTF-1), chromogranin A, synaptophysin, p53, Ki67, Fli-1, CD99, c-Kit] were evaluated in 20 cases of MCC. Fli-1 and CD99 were detected in 90% and 55% of cases, respectively. Tumour size > 30 mm, stage II, ‘absent’ lymphocytic infiltration, and the presence of > 50% of Ki67+ tumo…
Prognostic indicators for squamous cell carcinoma of the oral cavity: a clinicopathologic correlation.
1997
Fifty-three patients with T1 squamous cell cancer of the floor of mouth and ventral surface of the tongue with a known clinical outcome were retrospectively analyzed and arbitrarily divided into "aggressive" and "nonaggressive" groups based on their clinical behavior. Various host and tumor factors were then evaluated in an attempt to determine whether the tumor behavior could have been predicted. The paraffin-embedded tumor specimens were evaluated for tumor differentiation, tumor thickness and tumor invasion, microvessel density, and p53 expression. In addition, a composite morphologic grading score was obtained by combining cell differentiation, nuclear polymorphism, mitosis activity, de…
Biological aggressiveness evaluation in prostate carcinomas: immunohistochemical analysis of PCNA and p53 in a series of Gleason 6 (3+3) adenocarcino…
2003
We selected 63 prostate tumors with Gleason's grade 6 (3+3), commonly showing both tubular and cribrous patterns. We compared in both patterns the expression of two of the most used biologic markers: PCNA and p53, with the aim to verify the validity of the Gleason's grading system to compare the morphologic grade with biologic aggressiveness and prognostic value. We did not find any statistical difference in the protein immunopositivity, indicating that both patterns could have identical biologic behaviour; then we confirmed the validity of Gleason's system for considering both tubular and cribrous patterns as an intermediate grade of tumoral differentiation. Moreover, we found a linear rel…
Solitary Fibrous Tumor: Integration of Clinical, Morphologic, Immunohistochemical and Molecular Findings in Risk Stratification and Classification Ma…
2021
Although solitary fibrous tumors (SFTs) have an unpredictable evolution, some specific clinicopathologic factors have been associated with the final outcome. We retrieved clinical, pathological and molecular data of 97 patients with a histological diagnosis of SFT and Signal transducer and activator of transcription 6 (STAT6) positivity. We retrospectively studied the pathological factors predictive of recurrence/metastasis and compared them with the clinical outcome. A wide immunohistochemical study and molecular analysis to detect NAB2/STAT6 gene fusion, tumor protein-53 (TP53) and/or (telomerase reverse transcriptase) TERT promotor mutation were performed. The risk of metastasis was calc…
Expression of p53 Protein and Tumor Angiogenesis as Prognostic Factors in Nasopharyngeal Carcinoma Patients.
2002
The objective of this study was to evaluate the possible prognostic significance of p53 protein overexpression and tumor angiogenesis (TA) in nasopharyngeal carcinoma (NPC) patients, together with other clinicopathological variables. Forty-two NPC patients were evaluated in relation to survival. Nuclear p53 overexpression in neoplastic and endothelial cells was detected by immunohistochemistry (IHC) with the monoclonal antibody DO-7 and the polyclonal antibody against factor VIII-related antigen, respectively. Thereafter, we evaluated p53 cases in order to determine their nuclear immunoreactivity from negative (-) to positive (+, ++, +++). In addition, microvessels were counted in the most …
TP53 in gastric cancer: mutations in the l3 loop and LSH motif DNA-binding domains of TP53 predict poor outcome.
2004
The aim of this study was to clarify whether specific p53 mutations may have biological relevance in terms of disease relapse or death in gastric carcinomas (GC). Resected specimens from a consecutive series of 62 patients with GC undergoing potentially curative surgery were prospectively studied. The mutational status of exons 5-8 of the p53 gene was investigated in 62 cases using the PCR-SSCP and sequencing. Presence of microsatellite instability (MSI) was evaluated in 56 cases by analyzing loci highly sensitive of MSI. Twenty mutations of p53 were detected in 17 of the 62 cases analyzed (27%). Ten mutations (50%) occurred in highly conserved domains. According to the p53 specific functio…
CEP63 deficiency promotes p53-dependent microcephaly and reveals a role for the centrosome in meiotic recombination
2015
Artículo escrito por un elevado número de autores, solo se referencian el que aparece en primer lugar, el nombre del grupo de colaboración, si le hubiere, y los autores pertenecientes a la UAM
Immunohistochemical evaluation of PCNA, p53, HSP60, HSP10 and MUC-2 presence and expression in prostate carcinogenesis
2003
Background: The study of the expression of different biological markers in non-neoplastic, pre-neoplastic and neoplastic lesions of prostate could help to better understand their role in carcinogenesis and to find new diagnostic and prognostic tools. Materials and Methods: In the present work we evaluated, by immunohistochemistry, the presence and the expression of PCNA, p53, HSP60, HSP10 and MUC-2 in a series of nodular hyperplasia, low- and high-grade prostatic intraepithelial lesions and adenocarcinomas. Results: Our data confirmed that: 1) PCNA expression could be related to the grade of progression of cancer; and that 2) p53 mutation could be a late event in prostate carcinogenesis. Mo…
Identification of novel, clonally stable, somatic mutations targeting transcription factors PAX5 and NKX2-3, the epigenetic regulator LRIF1, and BRAF…
2021
Diagnosis of B-cell chronic lymphocytic leukemia (B-CLL) is usually straightforward, involving clinical, immunophenotypic (Matutes score), and (immuno)genetic analyses (to refine patient prognosis for treatment). CLL cases with atypical presentation (e.g., Matutes ≤ 3) are also encountered, and for these diseases, biology and prognostic impact are less clear. Here we report the genomic characterization of a case of atypical B-CLL in a 70-yr-old male patient; B-CLL cells showed a Matutes score of 3, chromosomal translocation t(14;18)(q32;q21) (BCL2/IGH), mutated IGHV, deletion 17p, and mutations in BCL2, NOTCH1 (subclonal), and TP53 (subclonal). Quite strikingly, a novel PAX5 mutation that w…
p53 mutations in L3-loop zinc-binding domain, DNA-ploidy, and S phase fraction are independent prognostic indicators in colorectal cancer: A prospect…
2002
p53 gene alterations are among the most common events observed in colorectal cancer,and are accompanied frequently by DNA aneuploidy and high proliferative activity. The prognostic significance of such mutations remains controversial. We prospectively evaluated the prognostic significance of p53 mutations, DNA-ploidy, and S phase fraction (SPF) in a consecutive series of 160 colorectal cancer patients (median follow-up 71 months). Tumor DNA was screened for p53 mutations by PCR/single-strand conformational polymorphism/sequencing. DNA-ploidy and SPF were assessed by DNA flow cytometry. p53 mutations were detected in 68 of 160 (42.5%) cases. In 56% (38 of 68) of these, p53 mutations were fou…