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)

The present study compared two microwave based antigen-retrieval solutions in their ability to unmask antigenic determinants in formalin-fixed and paraffin-embedded tissues for Immunostaining. In this regard, two widely used antigen-retrieval solutions, namely 0.05 M glycine-HCl buffer, pH 3.6, containing 0.01% (w/v) (EDTA) and 0.1 M sodium citrate buffer, pH 6.0, were evaluated for (1) their effectiveness in unmasking a wide range of antigenic determinants (2) their ability to yield reproducible results (3) the lack of deleterious effects in any antibody antigen systems of interest. Both of these antigen-retrieval solutions resulted in greatly improved immunostaining following microwave-heating of dewaxed tissue sections for 2 x 5 min. Glycine-HCl buffer solution resulted in stronger immunostaining with antibodies to nuclear antigens [androgen receptor (AR), estrogen receptor (ER), progesterone receptor (PR), p53, proliferating cell nuclear antigen (PCNA), Ki-67 and MIB-1], cytoplasmic antigens (actin and factor-VIII) and cell-surface antigens [Cu-18, epithelial membrane antigen (EMA) and MT-1 (CD43)], whereas sodium citrate buffer yielded superior immunostaining with antibodies to vimentin, and some cell-surface antigens [common leukocyte antigen (CLA) (CD45) and UCHL-1 (CD45RO)]. The effect of unmasking the epitopes recognized by antibody to PCNA was equally effective with either of the antigen-retrieval solutions. Antibodies to pan-keratin, prostatic acid phosphatase (PAP), B lymphocyte antigen (BLA.36, CD20CY) and L26 (CD20) exhibited no enhancement in the intensity of staining with either of the antigen-retrieval solutions.
 ...
PMID:Comparison of two microwave based antigen-retrieval solutions in unmasking epitopes in formalin-fixed tissue for immunostaining. 754 61

Histopathologic features alone fail to reliably stratify patients with clinical Stage A nonseminomatous germ cell tumors of the testis into groups with high and low risk for occult metastatic disease. Previous flow cytometric studies at Indiana University demonstrated a significant correlation between high proliferative activity and metastatic disease. The current study evaluated the prognostic significance of immunohistochemical markers related to tumor proliferation and aggressiveness in a consecutive series of clinical Stage A nonseminomatous germ cell tumors patients who underwent retroperitoneal lymph node dissection. Archival material of the orchiectomy specimens of 62 patients (45 pathologic Stage A, 17 with metastatic disease) was reviewed and immunohistochemically stained for Ki-67 antigen (MIB-1), proliferation-associated nuclear antigen (PC10), p53 protein (Pab1801), and Factor-VIII-related antigen (neovascularization). Staining with MIB-1 was significantly higher in the metastatic group (mean 80.2%, standard deviation [SD] 15.5) than in pathologic Stage A cases (66.3%, SD 27.9; P = 0.0032) and was predictive of metastatic status with a sensitivity of 82% and specificity of 69%. In this study, no patient with a MIB-1 value less than 52% had metastases. Proliferation-associated nuclear antigen and p53 staining correlated with MIB-1 values (R = 0.63 and 0.55, respectively) but did not correlate with metastatic status. Tumor angiogenesis was also not predictive of metastatic status. Assessment of proliferation rates using MIB-1 antibody in clinical Stage A nonseminomatous germ-cell-tumor patients may prove helpful in predicting metastatic status.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Prognostic significance of immunohistochemical proliferation markers (Ki-67/MIB-1 and proliferation-associated nuclear antigen), p53 protein accumulation, and neovascularization in clinical stage A nonseminomatous testicular germ cell tumors. 754 14

Gastric dysplasia (high-grade, HGD, and low-grade, LGD) and normal mucosa were tested for anti-p53, anti-Ki-67 and anti-PCNA monoclonal antibodies on paraffin sections, and for relative AgNOR area and number on semithin Epon-Araldite sections. The proliferative compartment in normal mucosa was restricted to the middle layer corresponding to the neck-isthmus region. In LGD and HGD there was an expansion of this compartment to the lower and upper layers of mucosa, and in HGD in particular to the upper layer. p53 was always negative in LGD as well as in normal mucosa, while it was positive in 34 out of 51 cases of HGD. The most discriminant variables between LGD and HGD were relative AgNOR area and the percentages of MIB-1, p53 and PCNA. In p53-positive HGD the highest percentages of PCNA and MIB-1 were in the middle and upper layers (PCNA) or the upper layer (MIB-1), while in p53-negative HGD cases cell proliferation was maximal in the middle layer, although also present in the upper layer. The majority of cases of LGD did not demonstrate cell proliferation in the upper layer, but 5 cases behaved similarly to the p53-negative HGD cases. No significant correlations were found among percentages of MIB-1 and of PCNA and relative AgNOR area and number.
 ...
PMID:Cell proliferation patterns and p53 expression in gastric dysplasia. 762 88

We report 25 cases of a peculiar sclerosing epithelioid variant of fibrosarcoma (SEF) simulating an infiltrating carcinoma. The tumors occurred primarily in the deep musculature and were frequently associated with the adjacent fascia or periosteum. The patients' ages were 14 to 87 years (median, 45). Fourteen were male and 11 female. The tumors were located in the lower extremities and limb girdles (12 cases), trunk (9), upper limb girdles (2), and neck (2). They measured 2 to 14.5 cm in greatest dimension (median size, 7 cm) and were gray to white and firm. Histologically, the lesions were characterized by a proliferation of rather uniform, small, slightly angulated, round to ovoid epithelioid cells with sparse, often clear cytoplasm arranged in distinct nests and cords. In all cases there was prominent hyaline sclerosis, sometimes reminiscent of osteoid or cartilage and foci of conventional fibrosarcoma. Occasional myxoid zones with cyst formation and foci of hyaline cartilage, calcification, and metaplastic bone were also seen. Mitotic figures were generally scarce. Vimentin was detected in 13 of 14 cases, epithelial membrane antigen in seven, S100 protein in four, and neuron-specific enolase in two. Cytokeratins were detected with AE1/AE3 and CAM 5.2 in two cases. Leukocyte common antigen, CD68 antigen, HMB45, desmin, and alpha-smooth muscle actin were negative in all cases. In 13 of 14 cases, 75% or more of the cells stained for proliferating cell nuclear antigen (PCNA). Ki67 immunostaining with MIB 1 showed low proliferative activity in all cases, averaging 5% of tumor cells or less. In all cases, p53 was detected by immunohistochemical methods; bcl-2, an antiapoptosis marker, was detected in more than 90% of the cells in 11 of 12 cases. Ultrastructurally, both the epithelioid and spindled tumor cells had features of fibroblasts. Follow-up in 16 cases ranging from 13 months to 17 years 3 months (median, 11 years 4 months) revealed persistent disease or local recurrences in 53% of patients and metastases in 43%. The metastases were to the lungs (4 cases), skeleton (3), chest wall/pleura (3), pericardium (1), and brain (1). Four patients died of disease, four were alive with disease, two were known to be alive but disease status unknown, and six had no evidence of further disease at last follow-up. The data suggest that SEF is a relatively low-grade fibrosarcoma; yet it is fully malignant despite the presence of histologically benign-appearing foci. The proliferation markers PCNA and Ki67 did not correlate with prognosis.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Sclerosing epithelioid fibrosarcoma. A variant of fibrosarcoma simulating carcinoma. 766 Dec 86

Alterations in the function of p53, a tumor suppressor gene, have been postulated as a principal underlying mechanism involved in the loss of cell cycle control in human malignancies. Because p53 dysfunction is generally associated with protein overexpression, immunocytochemistry is a valuable technique for the analysis of p53's functional status. We tested the hypothesis that loss of p53 function is a critical event in the early development and progression of human malignant melanoma and can lead to alterations in cell proliferation. We performed an immunocytochemical study in archival fixed, embedded specimens that included 102 melanocytic lesions ranging from benign nevi to metastatic melanoma. In addition to p53, we assessed the p53-associated protein, mdm-2, and markers of cell cycle status (the MIB-1-defined cell proliferation marker; proliferating cell nuclear antigen; and statin, a 57-kDa nuclear protein expressed preferentially by G0 cells). Tumor expression of all nuclear proteins was scored in a semiquantitative fashion related to the fraction of positive tumor nuclei. The overall incidence of significant p53 overexpression was low (8% of primary and 14% of metastatic melanomas). Analysis demonstrated strong correlation between increasing p53 expression in primary versus metastatic lesions (chi 2 analysis, P = 0.001). Correlation was found between increased MIB-1-defined cell proliferation and p53 overexpression in primary melanomas (P = 0.02). Detectable mdm-2 expression was significantly correlated with p53 overexpression (P = 0.02). Comparison of statin and proliferating cell nuclear antigen indices demonstrated inverse correlation (chi 2 , P = 0.03) in the combined groups, but within the metastatic group there was a subset of cases strongly expressing the two markers.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:p53 and mdm-2 expression in malignant melanoma: an immunocytochemical study of expression of p53, mdm-2, and markers of cell proliferation in primary versus metastatic tumors. 767 73

Mutations of the p53 gene often result in the overexpression of p53 protein. Previous studies have suggested that the function of p53 and its mutant protein forms may be linked with the disease course of patients with a breast carcinoma. In the present study, we tested 462 primary breast carcinomas for the presence of p53 antigen using immunohistochemical methods employing antibodies against the clone, DO-1. These tumors were also immunohistochemically stained using the monoclonal antibody, MIB-1, in order to demonstrate the presence of Ki67. Comparison of the presence of p53 with other prognostic parameters revealed highly significant negative correlations with estrogen- and progesterone-receptor status (P < 0.001 and P = 0.001, respectively) as well as positive correlations with both the presence of MIB-1 (P < 0.001) and the histological grading (P = 0.008). The presence of p53 was not correlated with tumor stage and node status. Evaluation of the findings for all 462 tumors as well as for node-positive and -negative subgroups revealed less favorable findings for overall survival and the disease-free period for both p53-positive tumors (for total group, overall survival, P = 0.0002, disease-free period, P = 0.02; for node-positive group, overall survival, P = 0.0004, disease-free period, P = 0.1045) and breast carcinomas with higher proportions of cell nuclei positive for MIB-1 (total, overall survival, P = 0.0026, disease-free period, P = 0.0022; node-positive, overall survival, P = 0.021, disease-free period, P = 0.0882). We were able to demonstrate that p53 expression in breast carcinomas means a significantly worse prognosis for grade II tumors (overall survival, P = 0.0002; disease-free period, P = 0.0116), for overall survival in the case of estrogen-receptor-positive tumors (P = 0.014), and for tumors showing increased proliferation activity (overall survival, P = 0.0477).
 ...
PMID:Usefulness of immunohistochemical staining for p53 in the prognosis of breast carcinomas: correlations with established prognosis parameters and with the proliferation marker, MIB-1. 770 8

Neuroblastoma, a tumor of the sympathetic nervous system, is one of the most common solid malignancies in infants and represents 7% of all cases of childhood cancer outside of the central nervous system. Thirty-five samples of neuroblastoma from 31 patients were obtained from Duke University Medical Center between 1979 and 1991 and studied to determine the relative prognostic value of a number of clinical, histologic, nuclear, and oncogenic features. The features studied were: stage, Shimada classification, DNA ploidy, MIB-1-proliferation index and status for HER-2/neu, p53 and epidermal growth factor receptor (EGFr). Only age (P = .03), HER-2/neu (P = .01), and p53 (P = .02) reached statistical significance as prognostic indicators. The median survival for patients with HER-2/neu expression was 12 months; median survival for patients with no HER-2/neu expression was 138 months. Similarly, the median survival for patients with p53 expression was 12 months; patients with no p53 expression had a median survival was 144 months. The combination of either HER-2/neu or p53 positivity was especially strong as a prognostic indicator (P = .002).
 ...
PMID:Prognostic indicators for neuroblastoma: stage, grade, DNA ploidy, MIB-1-proliferation index, p53, HER-2/neu and EGFr--a survival study. 774 72

The nature of perineurioma, variably termed "localized hypertrophic neuropathy," "intraneural neurofibroma," and "hypertrophic interstitial neuritis" has long been an issue of contention. Most authors consider it a neoplasm, but some a reactive process. Eight clinically and morphologically typical perineuriomas were studied by histologic, immunohistochemical and ultrastructural methods. One perineurioma was subject to tissue culture and cytogenetic study and another to fluorescence in situ hybridization (FISH) analysis. The patients, 3 males and 5 females, ranged in age from 11 to 38 years. All tumors were intraneural, and involved extremities (2 sciatic, 1 median, 1 femoral, 1 peroneal, 1 brachial plexus, 1 ulnar, and 1 radial). Neurologic symptoms, motor in all cases and sensory in 4, were present from 1 month to 7 years (mean 1.2 years). Fusiform, segmental nerve enlargement was clinically apparent in only two patients, but was evident on MRI in five of eight patients. Lesion length ranged from 3.5 to 30 cm, the largest involving the sciatic nerve from the obturator foramen to the knee. One lesion involved two nerve roots, but no association with a phakomatosis was noted. Treatment consisted of biopsy in six cases and resection in two cases. Histologically, pseudo-onion bulbs composed of epithelial membrane antigen-reactive, S-100 protein-negative perineurial cells surrounded myelinated or nonmyelinated nerve fibers. Many were accompanied by their S-100 protein-positive Schwann sheaths. Some whorls lacked a central axon. A single mitosis was noted in one case. The MIB-1 antigen labelling index ranged from 4% to 17%. Staining for p53 antigen in six cases showed no (2 of 6), rare (2 of 6), or scattered (2 of 6) immunoreactive nuclei. Cytogenetic analysis in one case demonstrated a chromosomally abnormal clone. Each of 16 metaphases was abnormal; the tumor cells appeared to be homozygously deficient for the region 22q11.2qter. In another case, 53% of interphase nuclei showed three FISH signals with a chromosome 14/22 probe, thus suggesting either monosomy for the centromere of chromosome 14 or that of chromosome 22.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Intraneural perineurioma. A clonal neoplasm associated with abnormalities of chromosome 22. 778 53

An immunohistochemical analysis with monoclonal antibodies against Ki-67 (MIB 1), PCNA (PC10), p53 and Lewis X antigen was performed on 47 squamous carcinomas of the larynx after partial laser resection. Ki-67 index and expression of Lewis X antigen correlated significantly with both tumor recurrence rate and tumor-free interval. A much weaker relationship was found for the expression of proliferating cell nuclear antigen (PCNA), and no correlation existed with p53 expression. In conclusion, examination of Ki-67 and Lewis X antigen is thought to provide useful prognostic information concerning laser-resectable squamous carcinomas of the larynx.
 ...
PMID:[Value of monoclonal antibodies (PC 10, MIB1, p53 and LeuM 1) for assessing the prognosis of patients with squamous epithelial carcinoma of the larynx after partial laser resection]. 779 71

Aberrant p53 immunoreactivity has been found in skin pre-malignancies and dysplasias such as Bowen's disease and actinic keratoses. Vulval lichen sclerosus (LS) has been reported to be pre-malignant, with an association of vulval carcinoma in 3% to 6% of patients. In contrast, non-genital LS appears to have no malignant potential. In this immunocytochemical study, we investigated p53 expression in 10 cases of histologically proven vulval LS and 9 cases of non-genital LS using the murine monoclonal antibody Do-1 raised against recombinant human p53 which reacts with both wild-type and mutant p53. None of the vulval specimens had epithelial dysplasia or malignancy. Normal vulval (7 cases) and non-genital skin (5 cases) were used as tissue controls, respectively. The cell proliferation index was also studied using the MIB 1 monoclonal antibody which detects the cell-cycle associated Ki-67 antigen. The technique of microwave irradiation for antigen unmasking was employed on formalin-fixed and paraffin-embedded tissues. There was a significant increase in p53 immunoreactivity in vulval LS (32.13 +/- 15.11 epidermal cells per 100 basal cells) compared to normal vulval skin (7.52 +/- 5.04 epidermal cells per 100 basal cells) (p < 0.001), whereas the MIB 1 labelling index was lower in vulval LS (39.45 +/- 15.88 epidermal cells per 100 basal cells) than in normal controls (86.26 +/- 32.31 epidermal cells per 100 basal cells) (0.001 < p < 0.01). In contrast, there was no significant difference in p53 immunoreactivity or MIB 1 labelling index between non-genital LS and normal controls.(ABSTRACT TRUNCATED AT 250 WORDS)
 ...
PMID:Altered p53 expression and epidermal cell proliferation is seen in vulval lichen sclerosus. 779 88


1 2 3 4 5 6 7 8 9 10 Next >>