Prognostic significance of Ki-67 and p53 antigen expression in carcinomas of bile duct and gallbladder

Ki-67 and p53 protein expression was evaluated immunohistochemically in 32 patients with intrahepatic, extrahepatic bile duct and gallbladder carcinomas, who underwent surgery at First Department of Surgery, The University of Tokushima School of Medicine. p53 expression was found more in the well differentiated group than poorly differentiated group (p = 0.007). MIB1 labelling index (MIB1 LI) was higher in EHC than in GBC (p = 0.0061). MIB1 LI (T), (MIB1 LI in tumor) was higher in cases with lymph node metastasis than in those without lymph node metastasis (p = 0.0189). Moreover, MIB1 LI (L) (MIB1 LI in metastasized lymph node) was higher in poorly differentiated than in well differentiated carcinoma (p = 0.0404). Prognostically, patients with high MIB1 LI (T) (> 56.93) had a worse prognosis after surgery than those with low MIB1 LI (T) (p < 0.05). There was no association between p53 positive tumors and MIB1 expression. These results suggest that cancer cell proliferative activity was markedly increased in cases with EHC compared to those with GBC and the poorly differentiated and lymph node metastasis group. MIB1 LI in tumor was found to be a good prognostic indicator whereas there was no association of p53 positive tumor with MIB1 expression and prognosis of the patients.     

Spindle cell carcinoma of the breast: a case report and an immunohistochemical study including p53 and Ki-67 expression

A rare case of spindle cell carcinoma (SpCC) of the breast occurring in a 51-year-old Japanese woman is reported. A firm and well-circumscribed tumor, measuring 9 x 8.5 x 8.5 cm, was located on the upper lateral region of the right breast. Microscopically, the tumor consisted of sheets of both malignant spindle cells and poorly differentiated ductal carcinoma containing squamoid islands with gradual transition to the spindle cell component. The immunocytochemical expression of epithelial markers was recognized in the spindle cells, as well as in the carcinomatous cells. Moreover, the spindle cell component expressed vimentin, alpha-smooth muscle actin and S-100 protein. Ultrastructurally, in addition to the features of adenocarcinoma, squamous or myoepithelial differentiation was confirmed in the spindle cell component. These findings thus suggest an epithelial origin with squamous differentiation and myoepithelial participation in the genesis of SpCC. In a comparative study, the expression of p53 protein and Ki-67 as a proliferation marker in each component of this tumor was also investigated. The mean p53 labeling index (LI) in both the carcinomatous and spindle cell area was similar, however the mean MIB-1 LI in the spindle cell area was significantly higher than that in the carcinomatous area. The results indicate that p53 overexpression is involved in the tumorigenesis of both components in the SpCC, and the spindle cell component shows a higher degree of proliferative activity than the carcinomatous component.     

Study on Ki-67 immunoreactivity as a prognostic indicator in patients with advanced gastric cancer

BACKGROUND: Cell proliferation characteristics may reflect the aggressiveness of gastric tumors and their eventual prognosis. The aim of this study was to evaluate whether the proliferative activities determined by the antibody Ki-67 could be used as a prognostic predictor in patients affected by advanced gastric cancer. METHODS: The prognostic significance of proliferative activity was investigated in 56 patients who underwent curative gastrectomy (R0) for advanced gastric cancer using the monoclonal antibody Ki-67. The patients were divided into three groups according to the Ki-67 labeling index of the tumors: < 10% (18 cases), 10-40% (21 cases) and > 40% (17 cases). The Cox regression model was used to evaluate the prognostic significance of the Ki-67 index controlling for age, gender, histology, depth of tumor invasion and node metastasis. RESULTS: There was no significant relationship between the Ki-67 index and wall invasion (P = 0.80) or nodal status (P = 0.73). The cumulative 3-year survival rates (95% Cl) were 61.0% (35.3-79.2%) in patients with Ki-67 index < 10%, 52.4% (29.7-70.9%) with Ki-67 index 10-40% and 52.9% (27.6-73.0%) with Ki-67 index > 40% and the differences were not statistically significant (P = 0.93). Also in multivariate analysis the proliferative activity did not independently affect survival (P = 0.98). An interaction between Ki-67 index and age was found and Ki-67 index > 40% was significantly associated with a poor prognosis in patients over 68 years old (P = 0.004). CONCLUSION: Our study indicated that the proliferative activity in gastric cancer, determined with the monoclonal antibody Ki-67, does not influence the survival except in elderly patients (> or = 68 years old).     

Prognostic value of immunohistochemistry for p53 in primary soft-tissue sarcomas: a multivariate analysis of five antibodies

Most changes of tumor suppressor p53 and its pathway involve a protein with prolonged half-life that permits immunohistochemical detection. The goal of this study was to compare the prognostic relevance of five different p53 antibodies in primary soft-tissue sarcomas (STS) with known p53 mutation status, using a multivariate Cox regression model (adjusted to tumor grading, staging, localization, tumor type, and therapy). A group of 198 primary STS of six types were investigated for p53 overexpression, using p53 antibodies DO-1, DO-7, Pab1801, Pab240, and CM-1. A positive marker frequency between 36.2% and 62.6% was detected. Out of 65 patients whose primary tumor reacted positively to all five antibodies, 52 (80%) died within the study period. Only the N-terminal-binding monoclonal antibodies DO-1, DO-7 and Pab1801 showed a multivariate correlation with survival (P = 0.0014, 0.0048 and 0.02). CM-1 and Pab240 had a univariate, but not a multivariate correlation, with a confounding effect of grading. The prognostic relevance for the five p53 antibodies was: DO-1 > Pab1801 > DO-7 > CM-1 > Pab240. This is the first study that investigates multivariately the prognostic relevance of p53 immunostaining in STS. If monoclonal antibodies with an epitope in the N-terminal region of the p53 protein (DO-1, Pab1801, DO-7) are applied, p53 immunohistochemistry provides an independent prognostic marker in STS.     

Molecular pathology in basal cell cancer with p53 as a genetic marker

Human basal cell cancer (BCC) has unique growth characteristics with virtual inability to metastasize. We investigated clonality and genetic progression using p53 mutations as marker. Sampling was done through microdissection of frozen immunohistochemically stained 16 microm slices of tumors. From 11 BCC tumors 78 samples were analysed. Direct DNA sequencing of exons 5-8 was performed, haplotypes were determined after cloning of p53 exons and loss of heterozygosity (LOH) ascertained by microsatellite analysis. All tumors had p53 mutations and in a majority both p53 alleles were affected, commonly through missense mutations. Microdissection of small parts (50-100 cells) of individual tumors showed BCC to be composed of a dominant cell clone and prone to genetic progression with appearance of subclones with a second and even third p53 mutation. Samples from normal immunohistochemically negative epidermis always showed wild type sequence, except for a case of previously unknown germline p53 mutation. Our analysis also included p53 immunoreactive patches i.e. morphologically normal epidermis with a compact pattern of p53 immunoreactivity. Mutations within those were never the same as in the adjacent BCC. This detailed study of only one gene thus uncovered a remarkable heterogeneity within a tumor category famous for its benign clinical behavior.     

DNA ploidy and MYC DNA amplification in ovarian carcinomas. Correlation with p53 and bcl-2 expression, proliferative activity and prognosis

There is increasing evidence that DNA ploidy is a prognostic factor in ovarian carcinomas, but it is uncertain whether MYC DNA amplification is an epiphenomenon of DNA nondiploidy or a distinct biological change with an impact on the clinical course of the disease. To clarify these issues we analysed DNA ploidy by flow and image cytometry and MYC copy number by polymerase chain reaction in archival material from ovarian carcinomas with known follow up. The results were compared with proliferative activity (Ki67 index) and p53 and bcl-2 expression. DNA cytometry revealed nondiploidy in 84 of 144 cases (58.3%). Nondiploidy was statistically significantly correlated with histological tumour type, histological grade, Ki67 index > 10%, FIGO stage, presence of residual tumour after debulking surgery and adverse postoperative outcome. Furthermore, DNA nondiploidy was associated with p53 accumulation. We found that 84.9% of the p53-positive cases were nondiploid. This points to the paramount importance of wild type p53 for the maintenance of genome integrity in this tumour type. MYC DNA amplification was seen in 33.8% (26/77 cases) of ovarian carcinoma. There was no correlation between MYC DNA amplification and histological tumour type, histological grade, FIGO stage, DNA ploidy, proliferative activity or prognosis. However, when p53 and bcl-2 expression was taken into account, a statistically significant correlation between gene alteration or expression patterns and histological tumour type was revealed. The group of mucinous carcinomas demonstrated both MYC DNA amplification and strong bcl-2 expression in 50% and contained the largest fraction of cases without aberration (37.5%). Endometrioid carcinomas were characterized by strong bcl-2 expression in 85%, whereas serous and undifferentiated carcinomas predominantly exhibited p53 alterations, frequently accompanied by bcl-2 overexpression or MYC DNA amplification. Thus, in interaction with other genes MYC DNA amplification may play a role in the determination of the varying differentiation patterns of ovarian carcinomas.     

bcl-2 but not p53 expression is associated with resistance to chemotherapy in advanced breast cancer

Programmed cell death is an important determinant of the response to chemotherapy. Among the factors controlling this process, a significant role is played by bcl-2 and p53, the expression of which, together with estrogen receptor content and tumor proliferative activity, was investigated by means of immunohistochemistry in 55 advanced breast cancer patients (median age, 60 years; range, 25-71 years). Analysis of bcl-2 expression identified two groups of patients with a significant difference in response rate. A total of 17 patients (31%) responded to chemotherapy (5 had a complete response and 12 had a partial response): 14 of 32 (44%) bcl-2-negative patients (< 40% stained cells) and only 3 of 23 (13%) bcl-2-positive patients (> or = 40% of stained cells; P = 0.019 by Fisher's exact test). The two groups were well balanced in terms of age, performance status, disease-free survival, menopausal status, and type of chemotherapy. bcl-2-negative tumors showed a tendency toward a higher p53 expression and proliferation rate, whereas an excess of bone as the dominant disease site was evident among the bcl-2-positive ones. However, the only variable to result significantly different between the two groups was estrogen receptor expression (P = 0.004). A multivariate logistic regression model showed that bcl-2 maintained its power of discriminating two groups with a different probability of responding to chemotherapy, although the greatest contribution was given by dominant disease site and type of chemotherapy. In conclusion, the results of this study suggest a possible role for bcl-2 in predicting resistance to chemotherapy.     

Mutant p53 expression: a marker of diminished survival in well-differentiated soft tissue sarcoma

The aim of this study was to assess the translational value of the quantitative assay of mutant p53 protein expression as both a prognostic indicator and a tool to determine appropriate therapy in a group of relatively innocuous and morphologically similar soft tissue sarcomas (STSs). Using a quantitative ELISA, we analyzed mutant p53 protein expression in 47 well-differentiated (grade I) STSs from patients treated in our Department of Surgical Oncology. Sixteen of 47 tumors expressed up to 42.6 ng mutant p53 protein/mg total protein. After a mean follow-up of 112 months, 63% of the patients with mutant p53+ tumors but only 16% of the patients with mutant p53- tumors had died (P < 0.01). Mutant p53 expression of >/=4.5 ng predicted even greater reduction in survival. These data show that mutant p53 expression identifies biologically aggressive grade I STSs. This molecular marker should have translational value as a tool to select those patients likely to benefit from aggressive multimodal therapy and intense surveillance.     

DNA topoisomerase II alpha and Ki-67 in human adrenocortical neoplasms: a possible marker of differentiation between adenomas and carcinomas

Cell kinetic information is valuable in evaluating the diagnosis and/or biologic behavior of various human neoplasms. Monoclonal antibody Ki-67 recognizes the cells other than G0 of the cell cycle. A cell cycle-related intranuclear protein, topoisomerase II alpha (topoII alpha), separates chromosomes at the end of mitosis. Its expression is mostly limited to the S to G2/M phases of the cell cycle. We studied cell proliferative activity in adrenocortical adenomas (n = 28), carcinomas (n = 17), and normal adrenal glands (n = 6) by immunohistochemical analysis of Ki-67 and topoII alpha to evaluate their value in the diagnosis of adrenocortical malignancy. We detected Ki-67 and topoII alpha immunohistoreactivity in the nuclei of each case we examined. There was a significant positive correlation (r = 0.927) between the Ki-67 and topoII alpha labeling indexes (LIs), the percentage of positive cells. In normal adrenal cortex and adenoma, the LIs for Ki-67 and topoII alpha were 0.48 +/- 0.16 and 0.44 +/- 0.15 for normal and 0.64 +/- 0.11 and 0.72 +/- 0.12 for adenoma, respectively, with no significant differences in the LIs of adenomas and normal adrenals. The Ki-67 and topoII alpha LIs in the carcinomas were 5.84 +/- 1.33 and 6.13 +/0 1.65, respectively; these LIs were significantly higher than the LIs of adenomas. Eleven of 17 carcinomas demonstrated topoII alpha and Ki-67 LIs of more than 2.5, whereas none of the adenomas did. The topoII alpha and Ki-67 LIs in carcinomas with metastasis (11.21 +/- 3.15 and 9.75 +/- 2.31 respectively; n = 7) were significantly higher than in those without metastasis (2.58 +/- 0.61 and 3.12 +/- 0.90, respectively; n = 10). This indicates that immunohistochemical analysis of Ki-67 and topoII alpha could help to differentiate carcinoma from adenoma in resected adrenocortical neoplasms and might predict aggressive biologic behavior in carcinomas.     

p53 expression in B-cell chronic lymphocytic leukemia: a marker of disease progression and poor prognosis

We have analyzed by immunocytochemistry (ICC) the frequency of p53 protein expression in 181 cases of B-cell chronic lymphocytic leukemia (CLL) followed at a single institution to assess the relationship between p53 and the clinical and morphological features of the disease, as well as the possible involvement of this protein in the pathogenesis of the more aggressive forms of CLL. The overall frequency of p53 protein positivity in CLL was 15% (27 of 181 cases). There were no significant differences in age, sex, absolute lymphocyte count, or lymphocyte doubling time between p53-positive and -negative patients. By contrast, p53-positive patients had a significantly higher percentage of prolymphocytes (P = .002) and a significantly lower percentage of residual CD3-positive T lymphocytes (P = .0001). No correlation was found between the percentage of p53-positive cells and the percentage of cells in cycle assessed by the monoclonal antibody Ki-67. When the percentage of p53 positivity was correlated with the clinical stage of the disease, the proportion of p53-positive cases increased significantly from Binet's stage A (8 of 108; 7.4%), to stage B (12 of 49; 24.4%) and C (7 of 24; 29.2%) (P = .002). p53 positivity correlated also with the phase of the disease, showing a low expression at diagnosis (8 of 112; 7.1%) and a significantly higher expression in patients studied during the course of the disease (7 of 35; 20%) and, to a further extent, with disease progression (12 of 34; 35.3%) (P = .0001). The association of p53 protein expression with mutations in the gene was confirmed by direct sequence of the entire cDNA in 15 of the 17 ICC positive cases tested (88%). A significantly shorter treatment-free interval from diagnosis (P = .003) and a poorer response to therapy (P = .007) was observed in p53-positive compared with p53-negative patients. Overall survival from the time of diagnosis, as well as from the time of p53 protein analysis, was significantly shorter in patients with p53 protein expression (P = .03 and .0001, respectively). Moreover, in multivariate analysis, p53 expression and stage C were independently associated with a short survival. The results of this study indicate that in CLL the expression of the p53 protein, analyzed by a simple and reliable immunocytochemical method, is strongly associated with p53 gene mutations, a morphological variant (CLL with >10% prolymphocytes), advanced clinical stage, progressive disease, poor response to therapy, and short survival.     

Expression of the cell cycle inhibitor p27KIP1 is a new prognostic marker associated with survival in epithelial ovarian tumors

This case-control study was designed to identify factors associated with long-term survival. We examined two groups of patients with epithelial ovarian cancer, one group of long-term survivors (> 5 years) and one group of short-term survivors (< 2 years), for levels of expression of p53 and p27KIP1 proteins (as both proteins have been shown to be independent prognostic markers in tumors other than ovary) and the relationship with patient survival. Our findings show that p27KIP1 expression, in contrast to p53 expression, is positively associated with long-term survival in univariate analysis (P = 0.001), in analyses stratified by residual disease (P = 0.02) or performance status (P = 0.02), the two strongest prognostic factors for ovarian cancer, as well as multivariate analysis (P = 0.002) adjusting simultaneously for age, tumor stage, residual disease, performance status, and grade of differentiation. Therefore, immunostaining for levels of p27KIP1 expression may have potential as a new prognostic factor in the management of ovarian cancer.     

p21WAF1/Cip1 expression is associated with cell differentiation but not with p53 mutations in squamous cell carcinomas of the larynx

The anti-metastatic effect of Z-100, an immunomodulatory arabinomannan extracted from Mycobacterium tuberculosis, was investigated in mice bearing B16 melanoma cells. Treatment of BF10 mice implanted with high metastatic B16F10 melanoma cells with a 10 mg/kg dose of Z-100 resulted in the reduction of experimental pulmonary metastasis as compared with that of BF10 mice treated with saline. The number of pulmonary metastatic colonies in BF1 mice (mice implanted with low metastatic B16F1 melanoma cells) was greatly increased after the inoculation of CD4+ CD11b+ CD281+ TCR alphabeta+ type 2 T cells (F10-Th2 cells) derived from BF10 mice, while only a few metastatic colonies were demonstrated in lungs of BF1 mice inoculated with naive CD4+ T cells. However, the numbers of metastatic colonies in BF1 mice were not increased when they were inoculated with the F10-Th2 cell fraction derived from Z-100-treated BF10 mice and the generation of F10-Th2 cells in BF10 mice was effectively suppressed by the Z-100 treatment. These results suggest that Z-100 inhibits pulmonary metastasis of B16 melanoma through the regulation of tumor-associated Th2 cells, which are a key cell in the acceleration of tumor metastasis.     

Clinical relevance of transforming growth factor alpha, epidermal growth factor receptor, p53, and Ki67 in colorectal liver metastases and corresponding primary tumors

To determine whether the expression of transforming growth factor alpha (TGF-alpha), its receptor (epidermal growth factor receptor [EGFr]), p53 nuclear protein, and proliferation influences prognosis of patients with liver metastases, a study was performed in 45 liver metastases and 33 corresponding primary colorectal carcinomas in patients referred for liver surgery. The expression of TGF-alpha, EGFr, p53 nuclear protein, and proliferation rate was correlated with clinicopathological characteristics and survival after partial liver resection. In liver metastases, TGF-alpha expression was low in 42%, intermediate in 35%, and high in 23%. TGF-alpha expression was higher in liver metastases derived from lymph node-positive primary carcinomas, in synchronous and in irresectable liver metastases compared with those derived from lymph node-negative primary carcinomas, metachronous, and resectable liver metastases. Nuclear p53 expression was found in 83% of primary tumors and 71% of liver metastases. p53 expression did not correlate with the various clinicopathological characteristics. Ki67 expression was not associated with clinicopathological characteristics in primary and metastatic tumors. In the 38 patients in whom a partial liver resection was performed, median survival was 25 months in patients with a higher TGF-alpha expression in the metastasis than in the primary tumor and 60 months in patients with comparable or lower TGF-alpha expression in the metastasis than in the primary tumor (P = .036). Median survival after liver resection was 21 months in patients with p53-negative liver metastases and 58 months in patients with p53-positive metastases (P = .043). By multivariate analysis, p53 and EGFr expression on liver metastases were the best predictors of disease-free survival after partial liver resection, with relative risks of 2.38 and 3.33, respectively. In patients with colorectal liver metastases, referred for liver surgery, a higher TGF-alpha expression is associated with unfavorable tumor characteristics, whereas p53 and absence of EGFr expression is associated with a better survival after partial liver resection.     

Reduced expression of cyclin-dependent kinase inhibitor p27Kip1 is associated with advanced stage and invasiveness of gastric carcinomas

Reduced expression of a cyclin-dependent kinase inhibitor p27Kip1 has recently been shown to predict poor survival of patients with breast and colorectal cancers. We studied the expression of p27Kip1 in gastric carcinomas by northern blotting, western blotting and immunohistochemistry to determine whether lack of p27 has implications for aggressiveness of gastric cancer. Reduced expression of p27 was detected in 40% of the gastric carcinomas at the mRNA level, while it was detected in 57% at the protein level. No gross alterations of the p27 gene were observed in any of the cases examined by Southern blot analysis. Immunohistochemical studies revealed that the expression of p27 was well preserved in most of the gastric adenomas, whereas it was so in only 26% of the gastric carcinomas. Fifty-six percent of the carcinomas showed almost no p27-positive cells. Decrease of p27-positive cells significantly correlated with advanced stage, depth of tumor invasion and lymph node metastasis. The expression of p27 showed an inverse correlation with the expression of cyclin E. These findings suggest that reduction of p27Kip1 protein may reflect the progression of gastric carcinomas and may be an indicator of high-grade malignancy.     

Use of in situ detection of histone mRNA in the assessment of epidermal proliferation: comparison with the Ki67 antigen and BrdU incorporation

The labelling index is commonly used as a measure of proliferation. However, the use of tritiated thymidine or BrdU labelling of S-phase cells is limited to prospective samples. We have employed an oligonucleotide cocktail complementary to the mRNA species encoding the replication-dependent histones H2B, H3 and H4 for non-isotopic in situ hybridization (NISH), and have compared the resultant proliferation indices in normal skin with those obtained by bromodeoxyuridine (BrdU) incorporation and by Ki67 immunohistochemistry (IHC) using the monoclonal antibody MIB1. In addition, we compared the staining characteristics of histone NISH and Ki67 IHC in a further 25 samples from a variety of inflammatory dermatoses and neoplastic conditions, as well as from normal skin. In normal skin, S-phase (histone NISH and BrdU) and cycling (Ki67) cells were confined to the basal and low suprabasal layers. The labelling indices determined by histone NISH and BrdU incorporation were similar, whereas that of Ki67 IHC was four times greater. In biopsies from hyperproliferative dermatoses and dysplastic or malignant lesions, the number of histone NISH- and Ki67 IHC-positive cells was generally elevated; in accordance with the differential expression of these two markers during the cell cycle, MIB1 consistently gave higher results. The advantage of histone NISH over Ki67 IHC is that it is a marker of the same part of the cell cycle as BrdU incorporation. However, the combined use of both histone NISH and Ki67 IHC to measure two cell cycle parameters, namely S-phase and the number of cycling cells, allows more detailed retrospective study of epidermal proliferation than has been possible previously.     

Locally recurrent prostate tumors following either radiation therapy or radical prostatectomy have changes in Ki-67 labeling index, p53 and bcl-2 immunoreactivity

Mast cells participate in the host defense against parasites. Mast cells release leukotrienes (LTs), potent 5-lipoxygenase (LO) products of arachidonic acid well-known to be involved in the inflammatory process. After incubation with Toxoplasma gondii, mast cells were found to degranulate and release LTB4; this interaction damages the tachyzoites. This mast cell activity against the tachyzoites was inhibited by the 5-LO inhibitor A-63162 and the 5-LO-activating protein inhibitor MK-886 but not by the cyclooxygenase inhibitor indomethacin. Reactive oxygen species were not implicated in the mast cell-mediated toxoplasmacidal activity. The generation of LTs is important for mast cell secretion, and LTB4 released by mast cells and other inflammatory cells may be a key factor in the host defense against T. gondii.     

p34cdc2 in invasive breast cancer: relationship to DNA content, Ki67 index and c-erbB-2 expression

AIMS: One-hundred and eighty-eight cases of human mammary carcinoma were examined immunohistochemically for their expression of Ki67, p34cdc2 and c-erbB-2. DNA image cytometry was performed to evaluate DNA ploidy, Auer type, S-phase fraction (SPF), 5c exceeding rate (5cER) and 2c deviation index (2cDI). METHODS AND RESULTS: One-hundred and sixty-eight cases were invasive ductal carcinomas, 20 were of invasive lobular type. Routinely assessed oestrogen and progesterone receptor scores were available. The results were analysed statistically in comparison to tumour type, histopathological grade, lymph node status, menopausal status, patient age and overall survival. Ki67 (P < 0.002) and c-erbB-2 (P < 0.0001) correlated well with overall survival (P < 0.0008) and grade (P < 0.038) but not with lymph node status and tumour type. p34cdc2 showed a trend towards a positive correlation with Ki67 (P < 0.058) and a significant negative correlation with receptor status (P < 0.008) but with none of the other parameters examined. CONCLUSIONS: No association between the DNA measured parameters (Auer type, SPF, 5cER and 2cDI) and survival was found. Our results suggest that c-erbB-2 and Ki67 are parameters which might, in combination with receptor status, help to define subgroups with different outcomes.     

p53 nuclear protein overexpression in colorectal cancer: a dominant predictor of survival in patients with advanced hepatic metastases

PURPOSE: To determine whether p53 protein expression is similar within primary colorectal cancer (CRC) and synchronous regional and distant metastases and to assess whether p53 nuclear protein expression could predict outcome in patients with synchronous unresectable liver metastases treated by hepatic artery infusional (HAI) chemotherapy. MATERIALS AND METHODS: Paraffin sections from tumor and corresponding normal mucosa representative of 50 consecutive advanced CRC cases were examined for p53 nuclear protein expression by immunohistochemistry using the monoclonal antibody PAb 1801. Patterns of p53 nuclear expression were correlated with standard clinicopathologic variables and outcome, including response to HAI and survival. In a subset analysis, the pattern of nuclear p53 immunoreactivity was compared between primary CRC and lymph node and liver metastases. RESULTS: Positive nuclear immunoreactivity for p53 protein was found in 72% of cases. The pattern of p53 protein expression in lymph node and liver metastases was identical to that of the primary tumor. The median survival time was 21.0 months in patients with p53-positive tumors and 53.2 months in patients with p53-negative tumors (Wilcoxon test P = .038). Two-year survival rates were 41.7% and 78.6%, respectively (P < .01). No significant difference was found in the response rates to HAI chemotherapy between the two groups. By multivariate analysis, p53 protein status was the single best predictor of survival, with a relative risk of 6.312. CONCLUSION: Our results indicate that nuclear p53 protein status in primary CRC is similar to that in metastatic sites and may be the dominant predictor of survival in patients with advanced hepatic metastases.     

Altered p53 is associated with aggressive behavior of chondrosarcoma: a long term follow-up study

BACKGROUND: p53 is a major tumor suppressor gene that has been implicated in the biology of a variety of human neoplasms, including some that affect the skeleton. Recent studies based on small numbers of cases have shown that overexpression or alteration of the p53 gene is frequently present in high grade, clinically aggressive chondrosarcomas of bone. In this study, the authors addressed the relation between overexpression and alteration of the p53 gene and the clinical aggressiveness of chondrosarcoma in a large series of patients for whom long term follow-up data were available. METHODS: The authors analyzed the expression and/or alteration of the p53 gene in 158 cases of chondrosarcoma of bone using immunohistochemistry, single-strand conformation polymorphism, and direct sequencing. They then related the findings to various clinicopathologic parameters and long term follow-up data. RESULTS: The presence of overexpression and/or structural alterations of the p53 gene was documented in 38.1% of chondrosarcomas of bone. A statistically significant correlation was observed between overexpression or alteration of the p53 gene and both the histologic grade of the tumor and the presence of metastasis. The probability of local recurrence free, metastasis free, and overall survival was significantly higher for patients with no overexpression or alteration of p53 than for patients with p53 overexpression or alteration. CONCLUSIONS: Overexpression or alteration of the p53 gene is an important predictor of aggressive clinical behavior in chondrosarcoma of bone.     

Genotypic analysis of tumor suppressor genes PTEN/MMAC1 and p53 in head and neck squamous cell carcinomas

OBJECTIVES: Tumor suppressor gene mutations in both p53 and PTEN/MMAC1 genomic DNA have been detected in many types of cancer. The purpose of this study was to investigate the presence and importance of PTEN/MMAC1 mutations in squamous cell carcinomas. METHODS: Exons of each gene were amplified after polymerase chain reaction (PCR) using genomic DNA derived from cell lines of squamous cell carcinoma of the head and neck (SCCHN) and snap-frozen biopsy specimens from primary established head and neck tumors. The amplified and purified DNA was then sequenced directly. RESULT: As anticipated, point mutations of the p53 gene were found in 80% of cell lines examined. A single base mutation in codon 151 was found in six of 10 cell lines studied. PTEN/MMAC1 gene mutations were found in neither the cell lines tested nor the tumor biopsy samples. CONCLUSION: This study, as well as a large volume of data, confirms that mutations of the p53 gene are frequent events in head and neck cancer cell lines. Although PTEN/MMAC1 gene mutations have been found in a variety of carcinomas, this gene was not found to be mutated in SCCHN cell lines or in primary squamous cell carcinomas of the head and neck. This information is useful for further studies of mutations in these cell lines.