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)

An E1B 55 kDa gene-deleted adenovirus, Onyx-015, which reportedly selectively replicates in and lyses p53-deficient cells, was administered by a single intratumoral injection to a total of 22 patients with recurrent head and neck cancer. The objectives of this Phase I study were to determine the safety, feasibility, and efficacy of this therapy and determine any correlation to p53 status. Six cohorts were investigated with a dose escalation from 10(7)-10(11) plaque-forming units. Toxicity was assessed using NCIC criteria. Tumor response was assessed by clinical and radiological measurement. Blood samples were taken to detect adenovirus DNA and neutralizing antibody to adenovirus. Tumor biopsies were taken to detect adenovirus by in situ hybridization. Treatment was well tolerated, with the main toxicity being grade 1/2 flu-like symptoms. Dose-limiting toxicity was not reached at the highest dose of 10(11) plaque-forming units. Twenty-one of the 22 patients treated showed an increase in neutralizing antibody to adenovirus. In situ hybridization showed viral replication in 4 of 22 patients treated, all of whom had mutant p53 tumors. Using conventional response criteria, no objective responses were observed. However, magnetic resonance imaging scans were suggestive of tumor necrosis at the site of viral injection in five patients, three of whom were classified using nonconventional criteria as partial responders, and two of whom were classified using nonconventional criteria as minor responders. Of these five cases, four had mutant p53 tumors. The response duration for the three partial responders was 4, 8, and 12 weeks. An additional eight patients had stable disease in the injected tumors lasting from 4-8 weeks. These preliminary results show that intratumoral administration of Onyx-015 is feasible, well tolerated, and associated with biological activity. Further investigation of Onyx-015, particularly with a more frequent injection protocol and in combination with systemic chemotherapy, is warranted.
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PMID:A phase I study of Onyx-015, an E1B attenuated adenovirus, administered intratumorally to patients with recurrent head and neck cancer. 1074 99

The family of tumor necrosis factor related apoptosis inducing ligand (TRAIL) receptors, including the pro-apoptotic DR4 and p53-regulated KILLER/DR5, as well as the decoys TRID and TRUNDD, are all located on human chromosome 8p21-22. This region of the genome is frequently altered in head and neck cancer. We previously reported that KILLER/DR5 can be mutationally inactivated in head and neck cancer. Here, we report that the FaDu nasopharyngeal cancer cell line contains an abnormal chromosome 8p21-22 region. In addition, there appears to be a homozygous deletion involving DR4 but not KILLER/DR5 in FaDu cells. The homozygous loss within the DR4 gene encompasses its death domain, which is required for apoptotic signaling. The deletion of DR4 in FaDu cells is associated with resistance to the cytotoxic effects of TRAIL. Re-introduction of wild-type DR4 leads to apoptosis and restores TRAIL sensitivity of FaDu cells. These observations suggest that the death inducing DR4 receptor gene may be a rare target for inactivation in human cancer and that DR4 loss may contribute to resistance to TRAIL therapy.
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PMID:Homozygous deletion of the death receptor DR4 gene in a nasopharyngeal cancer cell line is associated with TRAIL resistance. 1076 27

The expression of p53 and bcl-2 proteins by immunohistochemistry and the identification of human papillomavirus (HPV) infection by a non-isotopic polymerase chain reaction (PCR)based method were investigated in 30 patients with head and neck cancer. Ten cases were HPV-positive (33%), mostly as double or multiple infections by high- or intermediate-risk types. Twenty-one patients were p53-positive (70%), 9/10 with HPV-positive tumours and 12/20 with HPV-negative tumours; this difference was not statistically significant. Only four cases were bcl-2-positive, irrespective of the presence of either HPV or p53. No correlation was found between these biological factors and tumour stage, differentiation grade, and alcohol or tobacco use. Our findings indicate that p53 is involved in the majority of cases, bcl-2 is rare, and high-risk HPV could play a key role, especially in tumours of tongue and tonsil. In conclusion p53 and bcl-2 protein expression and the presence of HPV infection are independent events in these malignancies.
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PMID:Overexpression of p53 and bcl-2 proteins and the presence of HPV infection are independent events in head and neck cancer. 1076 95

The development of biological markers of response to chemo- and radiotherapy to judge benefit to risk ratios for toxic treatments is still at an experimental stage. Tumour cell death is largely by apoptosis and the p53 gene has a major influence on this. P-glycoprotein (P-gp) accumulation has been correlated with treatment failure in several types of cancer. p53 and P-gp expression were studied in 111 advanced head and neck cancers treated with radiotherapy and up to four courses of synchronous or sequential chemotherapy. The probability of survival at 5 years for patients in the trial as a whole was 27.7%, while the cohort used for this marker project was 29.4%. Among the subjects used for the marker study at the time of analysis, 13 remained disease-free and 18 were alive. Immunohistochemistry was used to assess p53 and P-gp expression; 27/111 (24%) head and neck cancers demonstrated p53/P-gp expression and 33/111 (30%) were both p53- and P-gp- negative. In univariate analysis, both p53 and P-gp expression were associated with reduced disease-free and overall survival. Multivariate analysis revealed tumour size, p53, and P-gp expression as the most powerful pretreatment prognosticators in the study cohort. Long-term follow-up results suggest that p53 and P-gp co-expression predicts the biological behaviour or the outcome following chemo/radiotherapy in advanced head and neck cancer.
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PMID:p53 and P-glycoprotein expression are significant prognostic markers in advanced head and neck cancer treated with chemo/radiotherapy. 1076 16

We and others recently isolated a human p53 homologue (p40/p51/p63/p73L) and localized the gene to the distal long arm of chromosome 3. Here we sought to examine the role of p40/p73L, two variants lacking the N-terminal transactivation domain, in cancer. Fluorescent in situ hybridization (FISH) analysis revealed frequent amplification of this gene locus in primary squamous cell carcinoma of the lung and head and neck cancer cell lines. (We named this locus AIS for amplified in squamous cell carcinoma.) Furthermore, amplification of the AIS locus was accompanied by RNA and protein overexpression of a variant p68(AIS) lacking the terminal transactivation domain. Protein overexpression in primary lung tumors was limited to squamous cell carcinoma and tumors known to harbor a high frequency of p53 mutations. Overexpression of p40(AIS) in Rat 1a cells led to an increase in soft agar growth and tumor size in mice. Our results support the idea that AIS plays an oncogenic role in human cancer.
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PMID:AIS is an oncogene amplified in squamous cell carcinoma. 1080 2

The prognostic and predictive role of c-erbB-2 oncoprotein in human malignancies remains controversial. The pattern of expression and the biological behaviour of c-erbB-2 protein was investigated in a series of 89 locally advanced squamous carcinomas of the head and neck. Possible associations between c-erbB-2 and T,N-stage, histological grade, microvessel density and the expression of bcl-2 and p53 proteins were sought. Biopsy material had been collected prior to the initiation of treatment which consisted of platinum based induction chemotherapy or concurrent chemotherapy and radiotherapy. In all cases, follow-up of at least 2 years duration was available. Positive staining was seen in 27 out of 89 (30.4%) cases and was invariably cytoplasmic, exhibiting strong reactivity in more than 50% of tumour cells. Such c-erbB-2 overexpressing tumours were not associated with a response to radiotherapy and/or induction chemotherapy. Further, survival analysis did not disclose any difference in the overall or relapse free survival between c-erbB-2 positive and negative cases. Similarly, no relationship was found with T,N-stage, histological grade and bcl-2 or p53 expression. There was, however, a significant inverse association between c-erbB-2 expression and microvessel density (p = 0.0001). Interestingly, tumours with low vascular grade (VG; MS < 26) and positive c-erbB-2 expression were less frequently associated with local aggressiveness compared to c-erbB-2 negative tumours and low VG (5/27 vs. 12/18; p = 0.001), or to c-erbB-2 negative tumours and high VG (MS > 27) (5/27 vs. 19/44; p = 0.03). These differences were statistically significant but were not related to treatment response or prognosis. Nonetheless, when patients with highly angiogenic tumours were analysed for survival, irrespective of the c-erbB-2 status, they showed a poorer prognosis than those having a low microvessel density (p = 0.06 and 0.05 for overall and relapse free survival, respectively). Six out of 89 patients presented with distant metastases, five of which had tumours negative for c-erbB-2 expression. Our results seem to indicate that the pattern of c-erbB-2 expression in locally advanced inoperable head and neck cancer is exclusively cytoplasmic. c-erbB-2 reactivity is of little value in predicting survival or chemo-radiotherapeutic response. Expression of genes related to angiogenesis or other invasion and migration pathways are, apparently, more important.
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PMID:c-erbB-2 oncoprotein is overexpressed in poorly vascularised squamous cell carcinomas of the head and neck, but is not associated with response to cytotoxic therapy or survival. 1081 Mar 87

Despite the introduction of screening procedures and an increased public awareness of prostate cancer, a substantial number of patients present with locally advanced prostate cancer. Traditional therapies (such as radiation therapy or radical prostatectomy) applied either alone or in combination fail to control local disease in a large number of cases and have no effect on disseminated disease. Recent advances in molecular oncology and genetics have led to such novel therapies as p53 gene therapy, which we are currently evaluating in a clinical protocol in patients with locally advanced (nonmetastatic) prostatic cancer. Ad5CMVp53 (RPR/INGN 201) has previously shown promise in both patients with lung cancer and those with head and neck cancer. The traditional end points used to appraise prostate cancer preclude rapid evaluation of the patient's disease and prevent modification of the therapeutic strategy, and we suggest that the pathologic stage after therapy be evaluated as an intermediate end point.
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PMID:Ad5CMVp53 gene therapy for locally advanced prostate cancer--where do we stand? 1085 46

Patients with advanced stages of head and neck cancer frequently develop locoregional recurrence as well as distant metastases. These data indicate that traditional diagnostic methods such as histopathology and radiology are not sensitive enough to detect the small numbers of tumor cells which are left behind, defined as minimal residual disease (MRD). Sensitive diagnostic assays based on molecular markers appear to be powerful tools to improve the staging of these patients. At the DNA level, tumor-specific p53 mutations seem to have great potential for the detection of "occult" tumor cells at surgical margins and lymph nodes. At the RNA level HNSCC associated antigens like the E48 antigen, allow the detection of rare HNSCC cells in blood and bone marrow and, it is hoped, also in lymph nodes and lymph node aspirates. However, the molecular assays which are used to detect MRD are subject to certain (technical) problems which affect their sensitivity and specificity. In this paper we will present examples of molecular assays such as the plaque assay using p53 mutations and the E48 RT-PCR, and show their use for MRD detection in cervical lymph nodes. In addition, we will discuss the problems and pitfalls associated with these sensitive techniques.
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PMID:Molecular diagnosis of head and neck cancer. 1085 64

Knowledge about the influence of biomarkers on cell proliferative activity might explain differences in radiosensitivity between head and neck tumors and might improve patient selection for the most optimal treatment strategy. p53 and bcl-2 protein expression were determined immunohistochemically in 56 head and neck cancer patients, treated by surgery only in five cases and by radiotherapy, with or without surgery, in 51 cases. Relationships with various cell proliferation markers, determined by flow-cytometry (G1-phase fraction, S-phase fraction, BrdUrd-labeling index, duration of S-phase and potential doubling time) were investigated. Associations between these cell proliferation parameters, on the one hand, and both p53 and bcl-2, on the other, were not found. Furthermore, p53 and bcl-2 expression were both not related to clinicopathological parameters (T- and N-stage, site, grade) and did not affect loco-regional recurrence-free survival and/or disease-free survival. We could not find a prognostic value for both p53 and bcl-2 protein expression to differentiate radiosensitive from radioresistant head and neck tumors.
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PMID:Influence of p53 and bcl-2 on proliferative activity and treatment outcome in head and neck cancer patients. 1088 20

p53 autoantibodies (AAB) are a fairly new serological parameter in patients with malignancies. Although the actual mechanism of how they develop is still unclear, it seems that these AAB could be of prognostic relevance. Very few studies demonstrated the usefulness of p53 AAB in the follow-up of cancer patients. In this study, 109 patients with head and neck cancer were investigated using an ELISA for the presence of p53 AAB in their serum and were followed-up for at least 36 months. In 21 of the cancer patients, p53 serum AAB were detected. In 5/21 p53-seropositive AAB patients, a correlation with the clinical course was observed. Sixteen of the p53-positive patients did not show any significant AAB titer changes during the follow-up, and no significant correlation with the clinical course was seen. According to these results, the clinical value of p53 AAB in the follow-up of patients with head and neck cancer seems to be limited.
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PMID:Serum p53 autoantibodies in the follow-up of head and neck cancer patients. 1089 64


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