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

Mutations of the p53 gene appear to be one of the most common abnormalities in human cancer. Although many studies have been published about p53 alterations in breast cancer, data on molecular biological detection of p53 mutations in in situ lesions are still rare, and the implications for breast cancerogenesis are unclear. Tissue samples from 83 patients with different stages of breast cancer and from 13 patients with benign breast lesions were screened for p53 gene mutations by polymerase chain reaction (PCR) followed by temperature-gradient gel electrophoresis (TGGE). p53 protein accumulation was analysed by immunohistochemistry (IHC). Samples were gained from fresh-frozen tissue, scrapings, or paraffin embedded tissue. Additionally, 23 pairs of primary tumours and corresponding lymph nodes were examined. p53 gene aberrations were found in 55.7% of the infiltrating carcinomas, in 31.5% of the ductal carcinomas in situ (DCIS) and in one atypical ductal hyperplasia. A positive correlation was seen with high-grade tumours and with comedo. There was no statistically significant relationship with respect to age, menopausal status, tumour size, hormone receptor status or lymphatic invasion. Concordance between TGGE and IHC was seen in only 63% of the cases analysed. However, with regard to p53 mutation screening by TGGE, a high significance (P = 0.0008) was seen between standard tissue extraction and our scrape preparation technique. Among 8 pairs of primary tumours and their corresponding lymph node metastases, only 3 harbored identical p53 mutations in the same exon, while in 5 cases with mutant p53 in the primaries, no mutation was seen in the lymph node. Our data indicate that p53 mutations are frequent in breast tumours associated with unfavorable prognosis, including high-grade or the comedo histotype. There is evidence that p53 gene alterations occur early in breast cancerogenesis, as mutations were detected not only in in situ carcinomas but also in atypical ductal hyperplasia.
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PMID:Molecular and immunohistochemical analysis of p53 mutations in scrapings and tissue from preinvasive and invasive breast cancer. 942 25

Expression of p53 protein was investigated by immunohistochemical techniques in archival cases of 134 primary breast carcinomas comprising 13 comedo ductal carcinoma in situ (DCIS), 105 invasive ductal carcinomas, 7 contained the comedo DCIS component adjacent to the invasive ductal component, 5 invasive lobular carcinomas, three colloid carcinomas and one medullary carcinoma. Overexpression of p53 gene product was studied to determine the association with clinico-pathological parameters and also its relationship to c-erbB2. Overexpression of p53 protein was observed in 31% (4/13) of comedo DCIS, 37% (39/105) of invasive ductal carcinomas, 57% (4/7) of carcinomas containing both the in situ and invasive lesions and all medullary carcinomas. A significant relationship (p < 0.05) was observed between strong immunoreactivity of p53 protein and absence of estrogen receptor, histological grade and c-erbB2 but not with lymph node metastases or age of patient. These observations suggest that overexpression of p53 protein may play an important role in tumor progression from noninvasive to invasive in some breast carcinomas and may have potential as an indicator for poorer prognosis.
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PMID:Immunohistochemical analysis of p53 expression in primary breast carcinomas. 956 57

In 74 in situ breast cancers an immunohistochemical study for estrogen (ER) and progesterone (PR) receptors, proliferation index (PI), and c-erbB-2, p53, and bcl-2 overexpression was performed. Cases were categorized as ductal carcinoma in situ (DCIS) comedo: 24.3% of cases; DCIS non comedo: 27% of cases; DCIS cribriform: 5.4% of cases; lobular carcinoma in situ (LCIS): 16.3% of cases; mixed carcinoma in situ: 27% of cases. Quantitation of immunohistochemical results was obtained with an image analysis computerized system (CAS 200). The cutoff values used were: 10% of positive area for ER, PR, NEU, and bcl-2; 5% of positive area for p53; 13% of PI for proliferative activity. DCIS cribriform and LCIS displayed a higher positivity for ER (92.6 and 93.8% of cases); DCIS cribriform and DCIS non comedo a higher for PR (89 and 75.3%); DCIS comedo presented the highest values for PI (65.4%), NEU (72.8%), and p53 expression (37.3%). All DCIS cribriform and DCIS non comedo and 99.6% of LCIS expressed bcl-2. The results underscore the importance of biological characterization of breast carcinoma in situ with the aim to define lesions natural history.
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PMID:Biological profile of in situ breast cancer investigated by immunohistochemical technique. 967 74

To reveal any association between the histological type and grade of intraductal breast neoplasms and the manner of accumulation of gene alterations, eight types of gene alterations, i.e., loss of heterozygosity (LOH) on chromosomal arms 16p, 16q, 17p, 17q, and 18q, amplification of the c-erbB-2 and hst-1/int-2 genes, and mutation of the p53 gene, were examined by Southern blot analysis or single-strand conformation polymorphism analysis in a total of 60 cases of intraductal breast cancer and 18 nonmalignant proliferative lesions. Among the histological types and three histological grade groups of intraductal carcinomas, the gene alterations which occurred most frequently were LOH on 16q alone in non-comedo type and Grade 1, alterations of c-erbB-2, 17p, and 16q in comedo type and Grade 2, and alterations of 17q and p53 as well as those of 16q, 17p, and c-erbB-2 in Grade 3. LOH on 16q and 18q was frequent in intraductal carcinoma of the intracystic papillary type, whereas LOH on 18q alone was detected in 27% of papillomas. Among intraductal carcinomas, the mean number of gene alterations was largest in comedo type and Grade 3, whereas it was smallest in non-comedo type and Grade 1. It was possible that LOH on 18q and 16q was involved frequently in papillary tumori-genesis and acquisition of malignant phenotype, respectively, whereas most of the other gene alterations were involved in acquisition of aggressive biological properties by intraductal carcinoma cells. It was also possible that the phenotype of breast neoplasms was determined by the combination of gene alterations at a relatively early developmental stage.
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PMID:Pattern of gene alterations in intraductal breast neoplasms associated with histological type and grade. 981 81

Expression of c-erbB3 protein was investigated in 104 primary breast carcinomas comprising nine comedo ductal carcinoma in situ (DCIS), 91 invasive ductal carcinomas and four invasive lobular carcinomas using two monoclonal antibodies, RTJ1 and RTJ2. Of the 91 invasive ductal carcinomas, seven contained the comedo DCIS component adjacent to the invasive component. An immunohistochemical technique was used to evaluate the association between expression of c-erbB3 and clinical parameters and tumour markers such as epidermal growth factor receptor (EGFR), c-erbB2, cathepsin-D and p53 in archival formalin-fixed paraffin-embedded tumour tissues. Our results indicated that RTJ1 and RTJ2 gave identical staining patterns and concordant results. It was found that the overexpression of c-erbB3 protein was observed in 67% (6/9) of comedo DCIS, 52% (44/84) of invasive ductal carcinomas, 71% (5/7) of carcinomas containing both the in situ and invasive lesions and 25% (1/4) of invasive lobular carcinomas. A significant relationship (P < 0.05) was observed between strong immunoreactivity of c-erbB3 protein and histological grade, EGFR and cathepsin-D, but not with expression of c-erbB2, p53, oestrogen receptor status, lymph node metastases or age of patient. However, we noted that a high percentage of oestrogen receptor-negative tumours (59%), lymph node-positive tumours (63%) and c-erbB2 (63%) were strongly positive for c-erbB3 protein. We have also documented that a high percentage of EGFR (67%), c-erbB2 (67%), p53 (75%) and cathepsin-D-positive DCIS (60%) were strongly positive for c-erbB3. These observations suggest that overexpression of c-erbB3 protein could play an important role in tumour progression from non-invasive to invasive and, also, that it may have the potential to be used as a marker for poor prognosis of breast cancer.
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PMID:Expression of c-erbB3 protein in primary breast carcinomas. 982 84

Carcinoma of the breast has an unpredictable biological behaviour. Several oncogenes have been implicated in the progression of breast cancer. Immunohistochemical staining of c-erbB-2 (Neu) oncoprotein and mutant p53 protein on 45 cases of infiltrating duct carcinoma (IDC) of the breast revealed 33% membrane positivity of c-erbB-2 oncoprotein, 46% nuclear positivity of mutated p53 protein, 33% and 84% membrane positivity of EGF-R and EMA respectively. Staining profile of c-erb-B2 oncoprotein in various histological subtypes of IDC of the breast indicated a high positivity rate in comedo followed by NOS and cibriform subtype. Similarly, high incidence of immunopositivity of mutated p53 protein was observed in comedo and cibriform subtypes while papillary carcinoma were found exclusively positive for mutated p53 protein. Interestingly, tubular subtype of IDC was not positive for c-erbB-2 oncoprotein as well as p53 mutant protein. Further, comedo and cibriform subtypes of IDC revealed 'high grade' histological features of tumour of the breast with high mitotic count, presence of marked pleomorphism and multinucleation thus, reflecting a positive relationship with overexpression of c-erbB-2 (Neu) oncoprotein as well as mutant p53 protein. The results on immunoexpression of c-erbB-2 oncoprotein and mutated p53 protein in various histological subtypes of IDC of the breast demonstrated c-erbB-2 status as an important predictor and also indicated that oncogene product may be involved in growth factor response pathway.
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PMID:Immunohistochemical co-expression of c-erbb-2/Neu oncoprotein, altered tumour suppressor (p53) protein, EGF-R and EMA in histological subtypes of infiltrating duct carcinoma of the breast. 1064 Nov 49

Apoptosis is a frequent phenomenon in breast cancer and it can be detected by light microscopy in conventional histopathological sections or by special staining techniques. The number of apoptotic cells as a percentage of cells present, or the number of apoptotic cells per square millimetre of neoplastic tissue, is usually described as the apoptotic index (AI). In breast cancer, the AI is not related to tumour size, axillary lymph node metastasis or distant metastasis at diagnosis. It is greater in invasive ductal carcinomas than in other histological types. High AI is also related to high histological grade, high nuclear grade, comedo-type necrosis, lack of tubule formation, and dense infiltration of the tumour by lymphocytes. Sex steroid receptor-negative tumours have greater AIs than the sex steroid receptor-positive ones. Aneuploid breast cancers with high S-phase fractions (SPFs) also have high AI values compared with diploid tumours with low SPFs. p53-Positive breast cancers have high AIs, whereas tumours that are Bcl-2 positive have low AIs. The AI shows a strong positive correlation to all direct or indirect indicators of cell proliferation, such as mitotic index and Ki67 immunolabelling. Univariate survival analyses show that a high AI is linked with unfavourable disease outcome in axillary lymph node-negative and -positive breast cancer, but multivariate analyses indicate that AI is not an independent prognostic factor. In conclusion, a high AI is related to malignant cellular features and indicators of invasiveness and cell proliferation in breast cancer.
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PMID:Apoptosis in breast cancer: relationship with other pathological parameters. 1073 80

Investigation of early breast carcinogenesis is limited by the difficulty in obtaining cell cultures or adequate fresh frozen material and by the fact that available data from in situ techniques are interpreted in terms of various classification systems. Our studies in a series of pure ductal carcinomas in situ (DCIS) were conducted in accordance with the recommendations of the international Consensus Conference (Hum. Pathol., 28, 122-125, 1997) relative to processing, determination of lesion extent, and histological stratification primarily on nuclear grade (NG). A multifactorial study performed in 15 low- and 16 high-NG DCIS (68% detected by mammography) included the following: (1) morphological analysis of NG, necrosis, and architectural pattern; (2) detection of numerical genomic abnormalities at ERBB2, MYC, CCND1, Xq1.2 and 20q13 loci by fluorescence in situ hybridization on interphase nuclei; and (3) immunohistochemical determination of cell proliferation, p53 accumulation, hormonal receptors and bcl-2 expression on serial sections of formalin-fixed, paraffin-embedded specimens. High NG, comedo/solid pattern and necrosis were significantly associated with amplification at one or more loci, the number of amplified loci, amplification at the ERBB2 locus, absence of bcl-2 and hormonal receptor expression and high cell proliferation (p < 0.05). High NG and comedo/solid pattern were significantly associated with MYC amplification and p53 accumulation, and necrosis with CCND1 amplification (the only gene amplification detected in low NG DCIS). These data provide additional information on the early steps of breast carcinogenesis, in accordance with currently recognized criteria of histological classification.
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PMID:Gene amplifications detected by fluorescence in situ hybridization in pure intraductal breast carcinomas: relation to morphology, cell proliferation and expression of breast cancer-related genes. 1100 1

p21Waf1 (p21), p27Kip1 (p27) and cyclin D1 have recently been reported as useful prognostic markers for patients with breast carcinoma. However, studies on these cell cycle regulators in ductal carcinoma in situ (DCIS) have been extremely limited. Therefore, we studied the immunohistochemical expression of p21, p27 and cyclin D1 proteins in 49 DCIS cases and compared the findings with the clinicopathologic parameters (age, tumor size, gross type, histologic type, histologic grade, necrosis and mitotic index), p53 and estrogen receptor (ER) status. A significant correlation was found between positive p21 immunoreactivity (67.3% of the cases) and well-differentiated histologic grade, non-comedo type, ER-positive and p53-negative (p53-) status. DCIS with p21+/p53- is likely to be the non-comedo type. The overexpression of cyclin D1 (59.2% of the cases) correlated positively with the ER expression (P = 0.001). The p27 protein expression (46.9% of the cases) correlated with the cyclin D1 immunopositivity (P = 0.0003) and ER expression (P = 0.005). No significant associations were seen in the p27 or cyclin D1 expression and other clinicopathologic parameters. Our results suggest that p21 might be more related to the useful biologic markers in DCIS than p27 or cyclin D1. The significant positive association between p21, p27 or cyclin D1 and ER status, and close association of p27 and cyclin D1 expression might be implicated in the tumor biology of DCIS.
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PMID:Expression of p21Waf1, p27Kip1 and cyclin D1 proteins in breast ductal carcinoma in situ: Relation with clinicopathologic characteristics and with p53 expression and estrogen receptor status. 1116 47

All cases of ductal carcinoma in situ (DCIS) diagnosed from 1987 to 1991 in the Southern Health Care Region of Sweden, and operated upon with breast conserving treatment (BCT) with (n=66) or without (n=121) postoperative radiation (RT) were clinically followed, morphologically re-evaluated and analysed for cell biological factors (immunohistochemical assays or DNA flow cytometry). Median age at diagnosis was 58 years (range 29--83 years) and median follow-up was 62 months. Oestrogen (ER)- and progesterone receptor (PR)-negativity, c-erbB-2 overexpression, low bcl-2 expression, p53 accumulation, DNA non-diploidy and high Ki67, were strongly associated with high grade DCIS, and comedo-type necrosis. In contrast, significant associations to growth pattern (not diffuse versus diffuse) were seen only for c-erbB-2 and PgR. There was also a strong relationship between the cell biological factors, and a summary cell biological index based on principal component analysis was introduced (CBI-7). In the group that had not received postoperative RT, 31 ipsilateral local recurrences occurred (13 invasive, 18 DCIS). Ipsilateral recurrence-free interval (IL-RFI) was in univariate analyses significantly, or almost significantly, shorter for patients showing p53 accumulation, high Ki67 or low bcl-2, compared with patients with normal p53, low Ki67 and high bcl-2. The prognostic importance of the remaining cell biological factors was less pronounced. On the other hand, the index CBI-7, was a strong predictor for recurrence.
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PMID:Cell biological factors in ductal carcinoma in situ (DCIS) of the breast-relationship to ipsilateral local recurrence and histopathological characteristics. 1150 59


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