Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UNIPROT:P04637 (p53)
 77,613 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Transcripts coding for transcription factors (RB, P53, FOS, MYC, MYB, ERBA, REL), growth factors (FGF1, FGF2, INT2, TGFA, TGFB, PDGF, IGF1, IGF2), interleukins, (IL1, IL2, IL3, IL4, IL6, TNF), growth-factor receptors or cytosolic protein kinases (RAF, PIM, FES, MET, SRC, ROS, TRK, KIT, CSFR, IGFR, PDGFR, EGFR, NEU) were quantified in cultured human mammary fibroblasts from normal tissues, benign tumours, carcinomas and post-radiation fibrosis lesions by slot-blot autoradiography and image analysis. The effects of a differentiating agent (cholera toxin) and of a tumour promoter (12-O-tetradecanoyl-phorbol-13-acetate) were also examined. The drugs modulated the levels of the anti-oncogene transcripts (RB, P53) and of ERBA, REL, RAF, MET, ROS, TRK, CSFR, EGFR, NEU, FGF1, INT2, IGF1, IL1, IL2, IL4 and IL6. Apart from this variation, there were multiple differences in gene expression among normal and pathological cells (concerning all but P53, TGFB and interleukin transcripts) and between sub-types defined by the presence of alpha-sm-actin (myofibroblasts) or EDB-fibronectin (RAF, ROS, FES, KIT, IGFR, NEU, INT2, TGFB, PDGF, IGFs, ILs). It appears, therefore, that mammary stroma progress irreversibly along with the epithelium during tumoral development, and that breast cancer is not only a multi-gene but also a multi-tissue phenotype.
 ...
PMID:Quantitative variation of proto-oncogene and cytokine gene expression in isolated breast fibroblasts. 776 44

The expression of oncogenes c-myc, c-jun and c-raf and tumour suppressor gene p53 was assessed by northern blot analysis of 42 tumours and p53 protein expression by immunohistochemistry on paraffin-embedded sections from 36 specimens of squamous cell carcinoma of the head and neck (SCCHN) obtained before therapy. Of the 42 tumours, 89, 100 and 100% expressed c-myc, c-jun and c-raf oncogenes, respectively. These oncogene expressions did not correlate with sex, age or clinical stage of the disease. However, an association was found between low c-myc expression (P = 0.0001) and high c-jun expression (P = 0.0001) and absence of tumoral response to neoadjuvant chemotherapy. On the other hand, c-raf overexpression was observed in patients resistant to radiation therapy (P = 0.0494). Forty-two per cent of the tumours showed p53 protein overexpression, which did not correlate with any clinical parameter. This p53 protein overexpression was associated with high p53 mRNA levels (REL) (P = 0.0223). A correlation was found between increased c-myc RNA expression and lack of p53 protein expression (P = 0.0407). In addition, a lack of p53 protein expression was indicative of tumour relapse (P = 0.05). None of these biological parameters were associated with disease-free survival (Cox-Mantel test). In conclusion, the overexpression of c-myc, c-jun and c-raf may be independently associated to tumoral response to chemotherapy or radiotherapy, or to tumour relapse, but fail to predict long-term survival.
 ...
PMID:Differential c-myc, c-jun, c-raf and p53 expression in squamous cell carcinoma of the head and neck: implication in drug and radioresistance. 874 69

Twenty primary central nervous system lymphomas (PCNSL) from immunocompetent patients (nineteen B-cell lymphomas and one T-cell lymphoma) were investigated for genetic alterations and/or expression of the genes BCL2, CCND1, CDK4, CDKN1A, CDKN2A, MDM2, MYC, RB1, REL, and TP53. The gene found to be altered most frequently was CDKN2A. Eight tumors (40%) showed homozygous and two tumors (10%) hemizygous CDKN2A deletions. Furthermore, methylation analysis of six PCNSL without homozygous CDKN2A loss revealed methylation of the CpG island within exon 1 of CDKN2A in three instances. Reverse transcription PCR analysis of CDKN2A mRNA expression was performed for 11 tumors and showed either no or weak signals. Similarly, immunocytochemistry for the CDKN2A gene product (p16) remained either completely negative or showed expression restricted to single tumor cells. None of the PCNSL showed amplification of CDK4. Similarly, investigation of CCND1 revealed no amplification, rearrangement or overexpression. The retinoblastoma protein was strongly expressed in all tumors. Only one PCNSL showed a mutation of the TP53 gene, i.e., a missense mutation at codon 248 (CGG to TGG:Arg to Trp). No evidence of BCL2 gene rearrangement was found in 11 tumors investigated. The bcl-2 protein, however, was strongly expressed in most tumors. None of the 20 PCNSL demonstrated gene amplification of MDM2, MYC or REL. In summary, inactivation of CDKN2A by either homozygous deletion or DNA methylation represents an important molecular mechanism in PCNSL. Mutation of the TP53 gene and alterations of the other genes investigated appear to be of minor significance in these tumors.
 ...
PMID:Frequent inactivation of CDKN2A and rare mutation of TP53 in PCNSL. 954 85

Common-variable immunodeficiency (CVI) patients develop non-Hodgkin's lymphomas (NHL), mainly B-lineage diffuse large-cell lymphomas (DLCL), with a high relative risk. The molecular pathogenesis of CVI-related NHL (CVI-NHL) is unknown. Here we aimed at providing a detailed molecular characterization of CVI-NHL. Rearrangements of BCL-6 were detected in two thirds of CVI-NHL cases examined. All 3 CVI-NHL also harbored point mutations of the BCL-6 5' noncoding regions, which constitute a marker of B-cell transit through the germinal center (GC). The number and molecular pattern of BCL-6 mutations in CVI-NHL were similar to that detected in DLCL of immunocompetent hosts and in DLCL arising in other immunodeficiency settings. Microsatellite instability occurred in one CVI-NHL devoid of a BCL-6 rearrangement. All CVI-NHL scored negative for genetic lesions of BCL-2, p53, c-MYC, REL as well as for viral infection by EBV and HHV-8. Overall, these data indicate that: similarly to other immunodeficiency-related NHL, involvement of BCL6 occurs frequently also in CVI-NHL; and because BCL-6 mutations are acquired by B cells during GC transit, their occurrence in CVI-NHL suggest that these lymphomas are histogenetically related to GC B cells.
 ...
PMID:Common-variable immunodeficiency-related lymphomas associate with mutations and rearrangements of BCL-6: pathogenetic and histogenetic implications. 1092 27

Genetic instability is a characteristic feature of the malignant Hodgkin and Reed-Sternberg (HRS) cells in classical Hodgkin's lymphoma and the lymphocytic and histiocytic (L&H) cells in lymphocyte predominant Hodgkin's lymphoma. Genetic instability can be classified into four major categories: distinct DNA mutations (microsatellite instability); numerical aberrations (chromosomal instability); structural aberrations (translocation instability); and gains and losses of chromosomal regions. In Hodgkin's lymphoma (HL), HRS cells and L&H cells show somatically mutated clonally rearranged immunoglobulin genes, thus characterizing these cells genetically as germinal center B cells. These cells furthermore show mutations of oncogenes and tumor suppressor genes in some cases (p53, IkappaBalpha, CD95/Fas). They do not, however, display microsatellite instability, as they have a proficient mismatch repair machinery. In contrast, HRS and L&H cells frequently harbor recurrent but not specific numerical and structural aberrations as detected by classical cytogenetics and fluorescence in situ hybridization analysis. Results from molecular genetic studies using comparative genomic hybridization and allelotyping (LOH) indicate typical genetic patterns in HL with gains and losses of distinct chromosomal regions. In some instances, candidate genes possibly involved in the malignant transformation of HRS cells and L&H cells have been characterized (JAK2, c-REL, MDM2). In summary, using molecular genetics it might be possible in the near future to elucidate some of the complex genetic instabilities observed in HL.
 ...
PMID:Genetic instability in Hodgkin's lymphoma. 1207 97

Genomic aberrations in a series of paired biopsy samples from patients who presented initially with follicle center lymphoma (FCL) and subsequently transformed to diffuse large B-cell lymphoma (DLBCL) were measured by array comparative genomic hybridization (CGH). The consequences of these aberrations on gene expression were determined by comparison with expression analysis on these specimens using cDNA microarrays. A heterogeneous pattern of acquired genomic abnormalities was observed upon transformation, some of which were recurrent in small subsets of patients. Some of the genomic aberration acquired upon transformation, such as gain/amplification of 1q21-q24, 2p16 (REL/BCL11A gene loci), 3q27-q29 (including the BCL6 locus), 7q11.2-q22.1, 12pter-q12, 18q21 (including the BCL2 locus) and Xq, and deletion of 6q22-q24, 13q14-q21 and 17p13 (P53 locus) have been previously implicated in the FCL/DLBCL pathogenesis. In addition, novel genomic imbalances not previously reported in association with FCL transformation, such as overrepresentation of 4p12-pter, 5p12-p15, 6p12.3-p21, 9p23, 9q13-q31, 16q, 17q21, and loss of 1p36.3, 4q21-q23, 5q21-q23, 9q31-qter, 11q24-q25, and 15q23, were identified. We observed a differential expression profile of many genes within regions of gain and deletion upon transformation, including novel target genes associated with FCL transformation. However, other genes did not show deregulated expression despite their location within these areas. In summary, the combination of array CGH and expression analysis provides a more comprehensive picture of the transformation of FCL to DLBCL. This process is associated with the acquisition of a variable spectrum of genomic imbalances affecting recurrent chromosomal areas that harbor overexpressed or underexpressed genes targeted upon transformation.
 ...
PMID:Transformation of follicular lymphoma to diffuse large cell lymphoma is associated with a heterogeneous set of DNA copy number and gene expression alterations. 1240 72

Controversy still exists over the response to therapy and prognosis of patients with primary mediastinal B-cell lymphoma (PMBL). Recent data from the International Extranodal Lymphoma Study Group (IELSG) suggest that a MACOP-B (methotrexate, adriamycin, cyclophosphamide, vincristine, prednisone, bleomycin) chemotherapy regimen followed by radiotherapy may be a better induction strategy than other previously used treatments. Although the pathobiology of PMBL has been widely studied, its precise histology, phenotype, and molecular characteristics are still not clear. To date, phenotypic analysis has revealed the following phenotype: positivity for CD45 and CD20, but negativity for CD3, CD10, CD21, Class I/II major histocompatibility antigens, and a variety of other immunohistochemical markers. CD79a is generally detected, despite an absence of surface immunoglobulins (Igs). CD30 staining is observed in most cases, but is weaker and less homogeneous than in classic Hodgkin's lymphoma or anaplastic large cell lymphoma. BCL-2 protein is usually expressed but there are few data describing the expression of MUM1/IRF4, PAX5/BSAP, BCL-6, or the B-cell transcription factors BOB.1, Oct-2, and PU.1. Cytogenetic studies reveal gains in segments of chromosome 9p, including amplification of the REL proto-oncogene and the tyrosine kinase gene JAK2. Other molecular findings include: C-myc mutations or rearrangements, p53 mutations, IgV(H), gene mutations, and bcl-2 and mal over-expression. bcl-6 mutations and bcl-2 gene rearrangements are generally absent, suggesting that PMBL is of pre-germinal center (GC) origin. However, two recent reports show isotype-switched Ig genes with a high frequency of somatic hypermutations as well as variants in the 5' noncoding region of the bcl-6 gene. The IELSG collected 137 PMBL cases for extensive pathologic review. Histologically, the lymphomatous growth was predominantly diffuse with sclerosis that induced compartmentalized cell aggregation. It consisted of large cells with varying degrees of nuclear polymorphism and clear to basophilic cytoplasm. Molecular analysis was performed on 40 cases and showed novel findings. More than half of the cases displayed bcl-6 gene mutations, which usually occurred together with functioning somatic IgV(H) gene mutations, and BCL-6 and/or MUM1/IRF4 expression. The present study supports the concept that PBML is derived from activated GC or post-germinal center cells. However, it differs from other aggressive B-cell lymphomas in that it shows defective Ig production despite the expression of Oct-2, BOB.1, and PU.1 transcription factors, and a lack of IgV(H) gene crippling mutations.
 ...
PMID:Pathobiology of primary mediastinal B-cell lymphoma. 1520 21

Activation of an oncogene via its juxtaposition to the IGH locus by a chromosomal translocation or, less frequently, by genomic amplification is considered a major mechanism of B-cell lymphomagenesis. However, amplification of an IGH/oncogene fusion, coined a complicon, is a rare event in human cancers and has been associated with poor outcome and resistance to treatment. In this article are descriptions of two cases of germinal-center-derived B-cell lymphomas with IGH/BCL2 fusion that additionally displayed amplification of an IGH/MYC fusion. As shown by fluorescence in situ hybridization, the first case contained a IGH/MYC complicon in double minutes, whereas the second case showed a BCL2/IGH/MYC complicon on a der(8)t(8;14)t(14;18). Additional molecular cytogenetic and mutation analyses revealed that the first case also contained a chromosomal translocation affecting the BCL6 oncogene and a biallelic inactivation of TP53. The second case harbored a duplication of REL and acquired a translocation affecting IGL and a biallelic inactivation of TP53 during progression. Complicons affecting Igh/Myc have been reported previously in lymphomas of mouse models simultaneously deficient in Tp53 and in genes of the nonhomologous end-joining DNA repair pathway. To the best of our knowledge, this is the first time that IGH/MYC complicons have been reported in human lymphomas. Our findings imply that the two mechanisms resulting in MYC deregulation, that is, translocation and amplification, can occur simultaneously.
 ...
PMID:Amplification of IGH/MYC fusion in clinically aggressive IGH/BCL2-positive germinal center B-cell lymphomas. 1585 72

This study was undertaken to further elucidate the biological mechanisms underlying the frequent event of transformation of follicular lymphoma (FL) to diffuse large B-cell lymphoma (t-FL). The gene expression profiles of 20 paired lymph node biopsies, derived from the same patient pre- and post-transformation, were analysed using the Lymphochip cDNA microarray. TP53 mutation analysis was performed and copy number alterations at the c-REL and CDNK2A examined. Immunohistochemistry was performed on an independent panel of paired transformation paraffin-embedded samples. Transformed follicular lymphoma was predominantly of the germinal centre B-like phenotype both at the mRNA and protein level. Despite this homogeneity, transformation proceeded by at least two pathways. One mechanism was characterised by high proliferation, as assessed by the co-ordinately expressed genes of the proliferation signature. This group was associated with the presence of recurrent oncogenic abnormalities. In the remaining cases, proliferation was not increased and transformation proceeded by alternative routes as yet undetermined. Genes involved in cellular proliferation prevailed amongst those that were significantly increased upon transformation and T cell and follicular dendritic-associated genes predominated amongst those that decreased. t-FL is a germinal centre B (GCB)-like malignancy that evolves by two pathways, one that is similar in proliferation rate to the antecedent FL and the other that has a higher proliferation rate and is characterised by the presence of recognised oncogenic abnormalities.
 ...
PMID:Transformation of follicular lymphoma to diffuse large B-cell lymphoma proceeds by distinct oncogenic mechanisms. 1727 62

Deletion of 17p (TP53) identifies a rare subset of chronic lymphocytic leukaemia (17p- CLL) with aggressive behaviour. Genome-wide DNA-profiling was performed to investigate 18 patients with 17p- CLL. All cases had multiple copy-number (CN) changes. Among the several recurrent CN changes identified, 8q24.13-q24.1-gain (MYC), 8p-loss (TNFRSF10A/B, also known as TRAIL1/2) and 2p16.1-p14-gain (REL/BCL11A) appeared frequently represented. 8p-loss and 2p16.1-p14-gain also appeared clinically relevant and predicted significant shorter time from diagnosis to treatment (8p-loss) and overall survival (8p-loss and 2p16.1-p14-gain, P < 0.05). These observations document a highly unstable genome in 17p- CLL and suggest that additional genes outside the TP53 locus may be important for tumour behaviour.
 ...
PMID:Genome-wide DNA analysis identifies recurrent imbalances predicting outcome in chronic lymphocytic leukaemia with 17p deletion. 1875 89


1 2 3 Next >>