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)

Significant clinical and biological differences are found between invasive squamous cell carcinoma (SCCA) and verrucous carcinoma (VC) of the oral cavity. The correct diagnosis of these tumors has important therapeutic implications. Immunoperoxidase stains for bcl-2, p53, and Her-2/neu, and in situ end-labeling of DNA to identify apoptosis were performed in eight VC and eight SCCA matched for age, sex, and stage. Marked differences were identified in the pattern of expression of oncogenes and the indexes of cell turnover in these two types of tumors. VC displayed minimal apoptosis in rare keratinizing cells (0 to 3%); p53-positive cells (4/8) and Ki-67 (8/8) were confined to the nuclei of the basal proliferating layers; and bcl-2 (4/8) was expressed only in the cytoplasm of rare tumor cells. In contrast, SCCA displayed higher apoptosis rates (5 to 10%), whereas p53- (5/8) and Ki-67- (8/8) positive nuclei were distributed randomly throughout the tumor. Very well differentiated areas in one SCCA case had a pattern of staining for p53 and Ki-67 similar to the one seen in VC. In SCCA bcl-2 showed patchy cytoplasmic staining (4/8) or strong cytoplasmic and nuclear positivity (2/8) in the less differentiated tumors. Her-2/neu was negative in all VC and SCCA cases. The different levels and patterns of gene expression and cell turnover between SCCA and VC undoubtedly correlate with the different biology and prognosis of these tumors.
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PMID:Comparative study of invasive squamous cell carcinoma and verrucous carcinoma of the oral cavity: expression of bcl-2, p53, and Her-2/neu, and indexes of cell turnover. 939 88

Rearrangements or loss of chromosome 17 are frequent events in breast tumors. Chromosome 17 contains at least four genes implicated in breast cancer (TP53, ERBB2 (Her2/neu), BRCA1, and NM23), as well as other putative tumor suppressor genes and oncogenes implicated in loss of heterozygosity or allelic imbalance studies. Allelic imbalance represents the addition or loss of genetic material in tumor samples, providing circumstantial evidence for the location of cancer related genes. We have analyzed a panel of 85 breast tumor/normal tissue pairs with 21 PCR-based short tandem repeat (STR) markers located at 17q12-qter to more precisely define regions of allelic imbalance and to determine their relation to clinical parameters. Our analysis revealed at least four common regions of allelic imbalance: proximal to BRCA1, including D17S800 (17q12); distal to NM23 around D17S787 (17q22); near the growth hormone (GH) locus, at D17S948 (17q23-24); and between markers D17S937 and D17S802 (17q25). These data also reveal that loss (or gain) of 17q genetic material correlates with poorly differentiated (grade III) tumors (P = < 0.001), high S phase fraction (P = 0.034), and positive TP53 immunohistochemical staining (P = 0.011). However steroid receptor status, ERBB2 (Her2/neu) staining, and aneuploidy do not correlate with allelic imbalance at 17q.
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PMID:Four regions of allelic imbalance on 17q12-qter associated with high-grade breast tumors. 940 51

The farnesyltransferase inhibitor L-744,832 selectively blocks the transformed phenotype of cultured cells expressing a mutated H-ras gene and induces dramatic regression of mammary and salivary carcinomas in mouse mammary tumor virus (MMTV)-v-Ha-ras transgenic mice. To better understand how the farnesyltransferase inhibitors might be used in the treatment of human tumors, we have further explored the mechanisms by which L-744,832 induces tumor regression in a variety of transgenic mouse tumor models. We assessed whether L-744,832 induces apoptosis or alterations in cell cycle distribution and found that the tumor regression in MMTV-v-Ha-ras mice could be attributed entirely to elevation of apoptosis levels. In contrast, treatment with doxorubicin, which induces apoptosis in many tumor types, had a minimal effect on apoptosis in these tumors and resulted in a less dramatic tumor response. To determine whether functional p53 is required for L-744,832-induced apoptosis and the resultant tumor regression, MMTV-v-Ha-ras mice were interbred with p53(-/-) mice. Tumors in ras/p53(-/-) mice treated with L-744,832 regressed as efficiently as MMTV-v-Ha-ras tumors, although this response was found to be mediated by both the induction of apoptosis and an increase in G1 with a corresponding decrease in the S-phase fraction. MMTV-v-Ha-ras mice were also interbred with MMTV-c-myc mice to determine whether ras/myc tumors, which possess high levels of spontaneous apoptosis, have the potential to regress through a further increase in apoptosis levels. The ras/myc tumors were found to respond nearly as efficiently to L-744,832 treatment as the MMTV-v-Ha-ras tumors, although no induction of apoptosis was observed. Rather, the tumor regression in the ras/myc mice was found to be mediated by a large reduction in the S-phase fraction. In contrast, treatment of transgenic mice harboring an activated MMTV-c-neu gene did not result in tumor regression. These results demonstrate that a farnesyltransferase inhibitor can induce regression of v-Ha-ras-bearing tumors by multiple mechanisms, including the activation of a suppressed apoptotic pathway, which is largely p53 independent, or by cell cycle alterations, depending upon the presence of various other oncogenic genetic alterations.
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PMID:A farnesyltransferase inhibitor induces tumor regression in transgenic mice harboring multiple oncogenic mutations by mediating alterations in both cell cycle control and apoptosis. 941 56

The clinicopathologic features of 32 metaplastic carcinomas with heterologous osteocartilaginous elements are reported. Each neoplasm consisted of invasive adenocarcinoma accompanied by a cartilaginous or osseous component. In 10 neoplasms, this consisted of cartilage and in 2 the heterologous element was osteoid or bone exclusively. The remaining 20 neoplasms contained a mixture of cartilaginous and osseous components. All patients were women; mean age was 56 years. Twenty-four patients were treated using mastectomy and eight by local excision. Twenty-six patients underwent axillary lymph node dissection. Lymph node metastases were detected in 6 of the 26 (23%) patients who underwent axillary dissection. Clinical follow-up was available for 29 of 32 patients (91%). Local recurrence or distant metastases developed in 6 patients (21%) within 2 years of initial treatment, and 4 of these patients died of metastatic carcinoma. The overall 5-year survival rate was 60%. When compared with control patients with infiltrating duct carcinoma, the group with metaplastic carcinoma tended to have a more favorable prognosis after adjustment for nodal status and tumor size. The prognosis of patients with metaplastic mammary carcinoma with heterologous osteocartilaginous elements is dependent on tumor stage at diagnosis. Immunohistochemical studies for 34BE12, p53, retinoblastoma protein, HER/2neu (polyclonal), epidermal growth factor receptor, and cyclin D1 were performed in 18 cases. Positive immunohistochemical staining was found as follows: 34BE12: n = 13 (72%); p53: n = 11 (61%); retinoblastoma protein: n = 12 (66%); HER2/neu: n = 2 (11%); epidermal growth factor receptor: n = 7 (38%); and cyclin Dm: n = 5 (28%). Positive staining for 34BE12 was observed in the carcinomatous component in 5 (38%) of the neoplasms, in the metaplastic component in 2 (15%), and in both elements in 6 (64%). A p53 staining was observed in the carcinomatous component exclusively in 4 (36%) of 11 p53-positive tumors. No disparity in p53 staining was noted between the epithelial and metaplastic elements in the other p53-positive tumors. Expression of these markers did not correlate with clinicopathologic features such as patient age, tumor size, tumor type, relative proportion of metaplastic elements, and axillary nodal status and was not predictive of disease-free survival.
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PMID:Metaplastic carcinoma of the breast with osteocartilaginous heterologous elements. 950 Feb 19

Pancreatic adenocarcinoma is one of the most incurable and least understood of all human cancers. It is the fourth leading cause of cancer-related mortality in males (after lung, prostate, and colon) and in females (after lung, breast, and colon) in the United States with <2-3% of patients surviving >5 years. In an attempt to search for more effective therapies for this disease, we report here, for the first time, an effective treatment, the combination of gemcitabine and auristatin-phenethylamine (PE), against an orthotopic implantation of a human pancreatic adenocarcinoma cell line (HPAC) in severe combined immunodeficient (SCID) mice. Tumor implantation was performed by injecting 100 microl of the HPAC cell suspension (1 x 10(6) cells) directly into the pancreas of 5-week-old SCID mice. After implantation, tumor formation was checked twice a week. All palpable tumors were detected within 21 days (100% take rate), and tumors were confirmed histologically to be pancreatic adenocarcinoma. For the subsequent efficacy trial, tumor-bearing SCID mice were randomized into four groups with five mice in each group. One served as a control, the second received gemcitabine alone (2.5 mg/kg/injection i.p.), the third received auristatin-PE alone (2.0 mg/kg/injection i.v.), and the fourth group received the combination of gemcitabine (i.p.) and auristatin-PE (1.5 mg/kg/injection i.v.). All animals were euthanized 7 days after the completion of their treatments, and the pancreases were resected. Histological examination revealed the tumors to be adenocarcinoma. The tumors were composed of diffuse sheets of cells interrupted by glandular spaces containing secretory material. Cytologically, the tumor cells were large, pleomorphic, and hyperchromatic. Many cells contained intracellular lumina containing mucin. Immunohistochemical studies showed strong p21WAF1 (p21) expression but no immunoreactivity with p53 and Her-2/neu antibodies. The mean pancreatic weight in the gemcitabine/auristatin-PE combination group was significantly (P = 0.014) lower (0.84 +/- 0.639 g) when compared with those of the control (2.91 +/- 1.19 g) and gemcitabine alone (1.84 +/- 0.796 g; P = 0.064) groups. In addition, the mean weight in the combination group approached statistical significance when compared with the auristatin-PE group alone (1.16 +/- 0.635 g; P = 0.028). We conclude that the combination of gemcitabine and auristatin-PE is an effective treatment against HPAC tumors in this xenograft model and more effective than treatment with either gemcitabine or auristatin-PE alone and could be considered for future animal studies with pancreas cancer and/or for human clinical trials.
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PMID:An orthotopic model of human pancreatic cancer in severe combined immunodeficient mice: potential application for preclinical studies. 956 82

To characterize the biological features of breast cancer associated with germ-line mutations in BRCA1 and BRCA2, invasive tumors were studied from 58 Jewish women ascertained through studies of early-onset breast cancer. All women were tested for the BRCA1 founder mutations 187delAG (commonly known as 185delAG) and 5385insC (commonly known as 5382insC) and the BRCA2 founder mutation 6174delT. Mutations were detected in 17 of 58 (29.3%) women. Comparing BRCA-associated breast cancers (BABCs) to cases arising in women without founder mutations, no differences were noted in tumor size, tumor stage, or frequency of axillary nodal involvement. Infiltrating ductal carcinoma was the predominant histological type in both groups. BABCs were significantly more likely to be of histological grade III (100 versus 63%; P = 0.04), estrogen receptor negative (75 versus 35%; P = 0.004), and HER2/neu negative (87 versus 58%; P = 0.04). An associated intraductal component was present in 59% of BABCs and 76% of cancers not associated with mutations (P = not significant). A high Ki-67 labeling index was more commonly observed in BABCs than in cases without mutations (83 versus 48%; P = 0.09). There were no differences between the two groups in the frequency of expression of epidermal growth factor receptor, cathepsin D, bcl-2, p27, p53, or cyclin D. There were no significant differences in relapse-free or overall survival. These observations suggest that breast cancers arising in Jewish women with germ-line BRCA founder mutations have a greater proliferative potential than cancers in women without such mutations. Additional studies of BABC are required to determine the nature and implications of additional genetic abnormalities occurring in these tumors.
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PMID:BRCA-associated breast cancer: absence of a characteristic immunophenotype. 958 22

Recurrent respiratory papillomatosis (RRP), usually confined to the nasopharynx, trachea, and larynx, occasionally can progress to extensive bronchopulmonary disease. Most cases of bronchopulmonary and laryngeal papillomatosis are cytologically benign and do not undergo malignant transformation; however, squamous cell carcinoma (SCC) can arise in RRP in the absence of known risk factors such as radiation and smoking. In this study, the authors investigated molecular genetic alterations occurring in a case of metastasizing SCC that arose in long-standing bronchopulmonary papillomatosis. Genomic DNA from tracheal papillomata, tracheobronchial papillomata, SCC of the lung, and a lymph node metastasis was extracted. The physical state of the human papillomavirus type 11 (HPV-11) DNA was investigated by two-dimensional gel electrophoresis. Molecular genetic alterations of the host genome were studied by direct sequencing of polymerase chain reaction-amplified gene fragments and restriction fragment length polymorphism (RFLP) analysis. Episomal and integrated forms of HPV-11 sequences were detected in histologically benign tumors, but only the integrated form of the viral DNA could be found in malignant tissue samples. Molecular genetic studies revealed that an allelic loss of the interferon-beta gene (IFNbeta-1) and an endogenous type of mutation of the p53 antioncogene were found only in the malignant lesions. Mutations were not observed in the ras, neu, or multiple tumor suppressor (MTS1/p16) genes in any specimens. The authors' data indicated that the p53 genetic mutation was associated with integration of HPV-11 in histologically malignant lesions. This association may promote a progressive genetic instability that can lead to the development and clonal expansion of malignant lesions in RRP.
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PMID:Malignant transformation of recurrent respiratory papillomatosis associated with integrated human papillomavirus type 11 DNA and mutation of p53. 959 56

Tumor size, axillary nodal status, histologic grading and the hormonal receptor status are the established prognostic factors for breast carcinoma. Concurrent to these factors the clinical validation of the new innovative tumor characteristics from molecular biology is difficult to achieve. Clinicians are more and more interested in indicators of response to particular treatments (predictive factors) and less in prognostic factors relevant for the natural course. The hormonal receptor status is the best known predictive factor with regard to the response to hormonal treatment. Among the innovative parameters the tumor suppressor gene p53 and the oncogene Her2/neu show a good correlation to sensitivity to cytostatic treatment. The detection of more and more molecular mechanisms of tumor growth and tumor spread raise hopes that innovative treatment approaches will lead to an antineoplastic effect. The molecular tumor parameters then may play the role of predictive factors for a specific treatment. For the present the established tumor factors should be used as the base for a treatment plan and the available already known predictive factors should be taken into consideration.
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PMID:[Relative indicators for disease outcome in breast carcinoma]. 960 45

IIB-BR-G is an undifferentiated, highly heterogeneous, hormone receptor negative human breast cancer cell line previously established in our laboratory from a patient's primary tumor. An in vitro growing cell line (IIB-BR-G) and a xenotransplanted tumor growing in nude mice (IIB-BR-G(NUDE)) were derived. To further characterize these systems, immunocytochemical analysis was performed for differentiation antigens (PEM 200 kDa, CEA, NCA 90 kDa), blood-group related antigens (Le(x), sTn), oncogenes and tumor suppressor gene products (Her-2/neu protein, p53), metastasis-related cathepsin D and CD63/5.01 Ag, and the chemokine monocyte chemotactic protein 1 (MCP-1). Expression of markers was heterogeneous in these different systems. Previously reported karyotypic analysis has shown extensive chromosomal alterations including double min. Searching for oncogene amplification, we detected augmented copy number of c-myc and c-fos, the last one with two rearranged fragments. No amplification was found for c-erbB-2 in the cell line or in IIB-BR-G(NUDE), although this oncogene was amplified in the patient's primary tumor DNA. The differences observed between the patient's tumor, the cell line and the IIB-BR-G(NUDE) tumors are probably due to clonal expansion of cell variants not present in the original tumor. Electron microscopy of IIB-BR-G growing cells revealed epithelial characteristics with abundant dense granules, presumably secretory, distributed all over the cytoplasm and great nuclear pleomorphism. In vitro, IIB-BR-G cells showed a significant number of invading cells by Matrigel assay. After nearly 40 sequential subcutaneous passages of the original xenograft through nude mice, 80% of recipients developed spontaneous metastases, primarily to the lung and lymph nodes. Since this experimental model allowed to analyze changes produced in cancer cells from the primary tumor during adaptation to in vitro and in vivo growth, our results provide novel insights on the behaviour of hormone independent metastatic breast cancer.
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PMID:The human breast cancer cell line IIB-BR-G has amplified c-myc and c-fos oncogenes in vitro and is spontaneously metastatic in vivo. 962 Apr 46

Significant progress is being made in understanding molecular events leading to lung cancer. Both susceptibility factors (molecular markers of risk) and the genetic alterations involved have been discovered. New techniques for early detection of lung cancer based on molecular changes (i.e. mutations in p53, K-ras and rb, amplification of myc and Her-2/neu, deletion of 3p, and microsatellite instability) in sputum or bronchoalveolar lavage fluid may be used as tools in diagnosis and prognosis, as well as in screening programs. These new findings should be transferred to the clinical environment. Multiple markers should be used, thereby increasing the chance of detecting the tumor or premalignant lesions. In the future, such research should be carried out in large prospective studies.
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PMID:[Lung cancer]. 969 5


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