P53 codon 72 polymorphism in breast cancer

Increased and deregulated proliferative activity due to abnormalities in the cell cycle modulators are frequently observed in cancer. A sequence polymorphism at codon 72 of the p53 gene results in either a proline or an arginine and may induce different functional activities. This polymorphism has been shown to have varying ethnic and geographical distribution. It has been reported that the p53 Arg homozygous genotype could be a potential genetic risk factor for cancer. However, not all investigations have been consistent and this hypothesized association remains controversial. The purpose of this study was to investigate the genotype frequencies and association of the p53 codon 72 polymorphism with breast cancer in Turkish patients. A group of 115 patients with breast cancer and a control group of 76 healthy individuals were enrolled in the study. A significantly higher prevalence of homozygosity for the p53 Arg allele was observed in the patients as compared to the controls. Statistical analysis suggested a strong association between the Arg/Arg genotype and breast cancer.     

乳腺癌中P53的表达与上皮-间质转化的相关性及其临床意义

  目的   探讨乳腺癌组织中P53的表达和上皮-间质转化（EMT）的相互关系及其临床意义。方法:免疫组织化学法检测63例乳腺癌组织中P53、Twist、Snail、E-Cadherin、N-Cadherin、Vimentin和Fibronectin的表达情况,分析乳腺癌突变型P53蛋白表达与临床病理特征,患者预后和EMT发生之间的关系。   方法   免疫组织化学法检测63例乳腺癌组织中P53、Twist、Snail、E-Cadherin、N-Cadherin、Vimentin和Fibronectin的表达情况,分析乳腺癌突变型P53蛋白表达与临床病理特征,患者预后和EMT发生之间的关系。   结果   P53、Twist和Snail的阳性率以及EMT的发生率分别为44.4%（28/63）、54.0%（34/63）、68.3%（43/63）和41.3%（26/63）。乳腺癌P53表达与组织学分级相关（P < 0.05）,与其他临床病理特征无关（P>0.05）。P53与Twist、Snail的表达存在相关性,而Twist、Snail和EMT发生相关（P < 0.05）。多因素分析显示,淋巴结转移、P53和EMT是乳腺癌患者预后的独立影响因素。   结论   P53的表达与乳腺癌组织学分级和EMT的发生相关,是患者预后的独立影响因素,可作为乳腺癌治疗的重要靶点。       

P-gp、p53过表达与胃癌及乳腺癌转移的关系

目的研究胃癌和乳腺癌组织P-耐药糖蛋白(P-gp),p53蛋白表达及临床意义.方法应用免疫组化SABC法检测93例胃腺癌组织及60例乳腺癌组织中p-gp、p53蛋白的表达.结果乳腺癌组织中P-gp阳性率为38.3%,p53阳性率为56.7%;胃腺癌组织中P-gp阳性率为55.9%,p53阳性率为44.1%;P-gp、p53蛋白表达均与淋巴结转移有关(P＜0.05)P-gp表达与p53表达有显著的协同性(P＜0.05).结论p53突变蛋白和P-gp过表达在胃癌和乳腺癌淋巴结转移中起重要作用.p53基因突变对于多药耐药基因(mdr-1)编码产物P-gp表达增高有一定影响,早期进行p53蛋白和P-gp检测有重要的临床意义.     

Luminal 型乳腺癌 P53表达与临床病理特征及预后的关系

目的：探讨 Luminal 型乳腺癌 P53表达与临床病理特征及预后的关系。方法选取2009年1月至2012年12月在上海交通大学附属第一人民医院手术治疗的283例 Luminal 型乳腺癌患者作为研究对象,采用免疫组织化学法测定 P53表达。生存分析采用 Kaplan-Meier 曲线评估和 Log-rank 检验比较,并用 Cox 比例风险回归模型进行单因素和多因素分析。结果 Luminal 型乳腺癌患者 P53表达与肿瘤最大径（χ2＝6．285,P ＝0．043）、淋巴结转移（χ2＝15．881,P ＝0．000）、组织分级（χ2＝8．132,P ＝0．043）、Ki-67（χ2＝6．476,P ＝0．039）有关;而与年龄（χ2＝0．955,P ＝0．328）、月经状态（χ2＝3．808,P ＝0．051）、病理类型（χ2＝0．847,P ＝0．655）、雌激素受体（χ2＝1．867,P ＝0．172）、孕激素受体（χ2＝0．937, P ＝0．333）及人表皮生长因子受体-2（χ2＝0．110,P ＝0．741）无关。在283例患者中,P53阴性组和阳性组5年无复发生存率分别为90．7％、66．7％（χ2＝12．609,P ＝0．000）,5年总生存率分别为93．4％、84．4％（χ2＝4．153,P ＝0．042）,差异均有统计学意义。Cox 多因素分析发现,淋巴结转移（HR ＝2．484,95％CI 为1．393～4．431,χ2＝9．497,P ＝0．002）和 P53阳性（HR ＝3．627,95％CI 为1．061～12．401;χ2＝4．220,P ＝0．040）是 Luminal 型乳腺癌患者无复发生存的独立危险因素;淋巴结转移（HR ＝3．451,95％CI为1．891～6．297;χ2＝16．290,P ＝0．000）和高组织学分级（HR ＝2．806,95％CI 为1．091～7．219;χ2＝4．582,P ＝0．032）是总生存时间的独立危险因素。结论 Luminal 型乳腺癌患者 P53过表达与淋巴结转移、组织分级等预后因素相关,且 P53过表达患者预后更差。     

P53 autoantibodies in 1006 patients followed up for breast cancer

During embryogenesis, the formation of primary vascular networks occurs via the processes of vasculogenesis and angiogenesis. In uveal melanoma, vasculogenic mimicry describes the 'embryonic-like' ability of aggressive, but not nonaggressive, tumor cells to form networks surrounding spheroids of tumor cells in three-dimensional culture; these recapitulate the patterned networks seen in patients' aggressive tumors and correlates with poor prognosis. The molecular profile of these aggressive tumor cells suggests that they have a deregulated genotype, capable of expressing vascular phenotypes. Similarly, the embryonic-like phenotype expressed by the aggressive human breast cancer cells is associated with their ability to express a variety of vascular markers. These studies may offer new insights for consideration in breast cancer diagnosis and therapeutic intervention strategies.     

P53 autoantibodies in 1006 patients followed up for breast cancer

Serial plasma samples from 1006 patients with breast cancer revealed: (i) no correlation of p53 autoantibody status with disease status at the time of sample collection, or with menopausal status at time of primary diagnosis of breast cancer; (ii) 155 out of 1006 (15%) of patients were positive for p53 autoantibodies, and these patients tended to have a persistent autoantibody status throughout follow up, irrespective of disease behaviour; and (iii) where a negative autoantibody status was found at primary diagnosis of breast cancer, this negative status persisted throughout follow up, irrespective of later disease behaviour. We conclude that screening for p53 autoantibody status is not informative on residual tumour activity nor on therapeutic responsiveness.     

HER-2, P53 and hormonal receptors protein expression as predictive factors in breast cancer prognosis

OBJECTIVE Breast cancer is a heterogeneous disease with variable biological and clinical characteristics. We conducted a study to evaluate P53, HER-2/neu and hormonal receptor expression as predictors of prognosis in breast cancer.
METHODS In a prospective study, we recruited 81 consecutive patients with primary operable breast cancer who were treated with mastectomy followed by locoregional radiotherapy or chemotherapy and studied the presence of P53, HER-2/neu and hormonal receptors （ER/PR） expression in tumor tissues by immunohistochemical staining. Associations between these markers expression and clinical outcomes, including local and regional recurrence and metastasis were evaluated. Statistical analysis was performed with the SPSS software.
RESULTS The mean time of follow-up was （47.3 ± 4.6） months. Expression of P53, HER-2/neu, Estrogen receptors and progesterone receptors were observed in 31.1%, 38.5%, 31.8% and 51.7% of the patients, respectively. P53, HER-2/neu and Negative ER status were potent predictors of local-regional recurrence （P = 0.034, 0.038, 0.044, respectively）. Also HER-2/neu, Negative ER and Negative PR status were strong predictors of metastasis （P = 0.001, 0.042, 0.054, respectively）. CONCLUSION P53 and HER-2/neu expression and also steroid receptors status （ER/PR status） have an important role in predicting the outcome of breast cancer and thus may be of value in selecting suitable therapeutic strategy and determining prognosis in these patients.     

P53 gene polymorphisms and breast cancer risk in Arab women

The association between polymorphisms in the p53 tumor suppressor gene and breast cancer risk has been studied in many human populations with conflicting conclusions. However, similar studies in Arab women are not available, and the status of these polymorphisms in this ethnic population is not known. We investigated the status of four known p53 gene polymorphisms and their possible role in breast cancer risk in Arab women. Genotyping was performed for 288 breast cancer women and 188 controls to determine Pro47Ser, Arg72Pro, Intron 3 Ins16 bp and intron 6 (G > C) polymorphisms. The p53 variant Pro47Ser was detected only in one Kuwaiti breast cancer patient and was not detected in any of the control subjects. Frequency of Arg/Arg at codon 72 was 26.6% in controls and 28.1% in patients, Arg/Pro frequency was 59.6% in controls and 69.4% in patients, the Pro/Pro genotype was 13.8% in controls and 2.4% in patients. We observed that women with Pro/Pro genotype have decreased risk for developing breast cancer (OR = 0.166, 95% CI = 0.067–0.411, p < 0.001). The intron 3 genotypes were A1/A1 (48.9%), A1/A2 (40.6%) and A2/A2 (10.5%) in controls and A1/A1(42.4%), A1/A2 (52.8%) and A2/A2 (4.8%) in cases. The intron 6 genotypes were 92.4% (GG), 7.6% (GC) and 0% (CC) in controls and 96.5% (GG), 3.5% (GC) and 0% (CC) in cases. No statistically significant differences between patients and controls were observed for intron 3 and intron 6 polymorphisms. Our data show that proline homozygosity at p53 codon 72 is associated with decreased breast cancer risk in Arab women.     

P73 functionally replaces p53 in Adriamycin-treated, p53-deficient breast cancer cells

p53-Related genes, p73 and p63, encode 2 classes of proteins, TA-p73/p63 and DeltaN-p73/p63. TA-p73/p63 demonstrate p53-like properties including gene transactivation and cell death promotion, whereas DeltaN-p73/p63 lack these p53-like functions. Although p53-deficient cancer cells are often less responsive to chemotherapy, they are not completely drug resistant, suggesting that other apoptotic pathways are at work. Here, we compared for the first time to our knowledge p73 and p63 activation in various breast cancer (BC) cell lines after Adriamycin (ADR) treatment, an agent considered as mandatory in breast cancer chemotherapy. Our study was carried out using 1 p53-proficient BC cell line (MCF7 cells) and 3 BC cell lines deficient in p53 response (MCF7/ADR(IGR), MDA-MB157 and T47D) after ADR-induced genotoxic stress. We report that in cells with no p53 response after ADR treatment, TAp73, but not TAp63 or DeltaN-p73/p63, may replace p53 in triggering not only apoptosis but also cell cycle arrest or DNA repair effectors such as p21, GADD45, 14-3-3sigma and p53R2. We also demonstrate that TAp73 siRNA inhibits the accumulation of TAp73 in response to ADR treatment in MDA-MB157 cells and confers protection against ADR. ADR-induced downregulation of the DeltaNp73 isoform in the T47D cell line with nonfunctional mutant p53 further supports anti-apoptotic function of the isoform antagonistic to both p53 and TA-p73/p63. Exogenous TAp73 and DeltaNp73 overexpression in p53-response-deficient cell lines further confirms these results. cDNA microarray techniques demonstrated that the cellular response induced by p73 during ADR treatment could involve specific genes.     

P53 expression is a factor for prognostic assessment in breast sarcoma

The present study was undertaken with the aim of evaluating the clinical and anatomopathological findings, emphasizing expression of the protein p53 as possible prognostic markers, in patients with breast sarcoma. p53 immunohistochemical expression was determined in archival paraffin embedded tissue blocks of 30 breast sarcoma patients, (19 fibrosarcomas, nine malignant fibrohistiocytomas and two liposarcomas) treated at the Hospital do Câncer AC Camargo, São Paulo, Brazil from 1955 to 1990. Immunopositivity was present in 50% of the cases. The survival of the patients was compared with the above parameters. Median follow up time was 113 months. The 5 years specific survival rates were 55.1% for patients with a positive expression of p53 contrariwise to 92.3% of specific survival found in p53 negative patients (p=0.04). Positive expression of p53 was found in 3/4 (75%) of the patients with local recurrence and in 7/9 (77%) of patients with metastatic disease. No significant correlation between survival and clinicopathologic features (age, menopausal status, tumor size, stage and histological type), was found. A slight positive correlation between high grade and poor outcome was observed, 89% of the metastatic cases being classified as high grade (p=0.02, by one sided Fisher's exact test). When we have compared, independently, survival probability curves between p53 positive/negative expression and each category of clinicopathologic features a worse prognosis was observed when p53 was positive in patients older than 50 years (p=0.01), in tumors larger than 5cm (p=0.02), within the malignant fibrous histiocytoma subtype (p=0.01) and in tumors classified as high grade (p=0.07). In conclusion p53 expression seems to be a useful prognostic marker for this type of tumor.     

P7 antigen expression in human breast cancer.

PURPOSE: Evaluate p7 expression in human breast cancer and determine whether chemotherapy and radiation therapy effect a change in p7 expression. EXPERIMENTAL DESIGN: Using a p7-specific monoclonal antibody with immunohistochemistry and Western immunoblot analyses to assess p7 expression in archival, frozen breast cancer specimens both before and after therapy. RESULTS: A novel 7 kDa protein (p7), originally identified in multidrug-resistant ovarian and breast cancer cell lines, was found to be expressed in 21 of 64 (32%) primary, unselected human breast cancer specimens by immunohistochemistry with the use of a p7-specific monoclonal antibody, 1D7. P7 was observed in malignant cells but not in other types of cells in the breast tissue. Western blot analysis confirmed the 7 kDa polypeptide in p7-positive breast carcinomas identified by immunohistochemistry. P7 expression was significantly associated with breast cancers having distant metastasis and/or local recurrence (P = 0.027, Fisher's exact test). In addition, p7 expression was significantly increased in post-treatment breast cancer biopsy specimens compared with pretreatment breast cancer biopsy specimens in patients with locally advanced breast cancer after 5-fluorouracil chemotherapy and radiation therapy [2 of 15 (13%) pretreatment breast cancers compared with 8 of 15 (53%) post-treatment breast cancers; P = 0.016, McNemar's test]. CONCLUSIONS: These findings demonstrate that expression of p7 is associated with malignant tumor cells in primary breast cancers, especially those showing recurrent or metastatic disease. Its specific association with the malignant phenotype suggests it may have potential for novel target-based therapies. The markedly increased expression in patients with locally advanced disease after neoadjuvant therapy suggests a role for p7 in treatment outcome.     

三阴性乳腺癌中p53蛋白表达的Meta分析

目的:评价三阴性乳腺癌与p53蛋白表达的相关性,为提高三阴性乳腺癌个体化治疗提供参考。方法:通过PubMed、Web of Science、CNKI、WanFang data、VIP数据库检索相关文献,检索时间为2005年至2020年。由两位研究者按照文献的纳入与排除标准进行文献筛选、资料提取、质量评价,最后采用RevMan 5.3软件进行Meta分析。结果:纳入文献36篇,其中中文文献29篇,英文文献7篇。结果显示:三阴性乳腺癌组p53的阳性表达率高于非三阴性乳腺癌组［OR=2.29,95%CI(2.06,2.55)］,p53阳性组的淋巴转移率高于p53阴性组［OR=1.96,95%CI(1.20,3.18)］,差异具有统计学意义;而p53的阳性表达与三阴性乳腺癌的TNM分期无关［OR=0.49,95%CI(0.08,2.90)］,差异没有统计学意义;三阴性乳腺癌p53阳性组的总生存率低于p53阴性组［OR=0.36,95%CI(0.23,0.56)］,差异具有统计学意义;三阴性乳腺癌p53阳性组的无病生存率低于p53阴性组［OR=0.32,95%CI(0.23,0.45)］,差异具有统计学意义;三阴性乳腺癌患者的年龄与p53的阳性表达没有相关性［OR=1.17,95%CI(0.83,1.65)］,差异没有统计学意义。结论:p53的表达与三阴性乳腺癌的发生、发展及预后密切相关,并且可能成为预测三阴性乳腺癌发生发展的独立因子。     

Gene expression patterns associated with p53 status in breast cancer

Background  

Breast cancer subtypes identified in genomic studies have different underlying genetic defects. Mutations in the tumor suppressor p53 occur more frequently in estrogen receptor (ER) negative, basal-like and HER2-amplified tumors than in luminal, ER positive tumors. Thus, because p53 mutation status is tightly linked to other characteristics of prognostic importance, it is difficult to identify p53's independent prognostic effects. The relation between p53 status and subtype can be better studied by combining data from primary tumors with data from isogenic cell line pairs (with and without p53 function).     

P53, Bcl-2 expression and cell proliferation in benign breast lesions

The role of proliferation-related markers on breast cancer pathogenesis has been only occasionally investigated. The immunocytochemical expression of P53 and Bcl-2 (using PAb1801 and anti-bcl-2 monoclonal antibodies) and cell proliferation (evaluated as the H-3-thymidine labeling index [H-3-dT LI]) were determined on 62 benign breast lesions at different risk. Accumulation of the P53 protein was never observed; Bcl-2 was detected in 50% of cases and it was unrelated to biologic and clinicopathologic features. Median H-3-dT LI was about three times lower than that observed on large series of invasive breast cancer. It was only slightly higher in lesions from patients younger than 35 years or with a positive family history than in those under 35 or with a negative family history and appeared unrelated to histology or risk classification. Such findings indicate that the investigated biomarkers fail to identify women at increased risk for breast cancer.     

The R72P P53 mutation is associated with familial breast cancer in Jewish women

BRCA1/BRCA2 mutations account for a substantial proportion of familial breast cancer, but clearly mutations in additional genes exist, one candidate being the p53 gene. To evaluate its putative involvement in inherited predisposition to breast/ovarian cancer in Jewish high-risk women, mutational analysis of the p53 gene (exons 4-9) was carried out using exon-specific polymerase chain reaction followed by denaturing gradient gel electrophoresis (DGGE) analysis, complemented by DNA sequencing of abnormally migrating fragments. Overall, 132 Jewish breast cancer patient non-BRCA1/2 mutation carriers and 167 average risk controls (Ashkenazi (n=60), non-Ashkenazi (n=107)) were genotyped, and no inactivating p53 germline mutations were detected. Consistent migration abnormalities were noted in 167 fragments, 134 of which were shown to be the Arg72Pro polymorphism, whereas migration abnormalities in fragments containing exons 4 (n=2) and 6 (n=23) and introns 3 (n=4) and 9 (n=4) corresponded to five previously described polymorphisms. Allele distribution of the R72P missense mutation between ethnically diverse Jewish breast cancer cases and average risk controls showed significant differences: among non-Ashkenazi breast cancer cases, 62.5%, 33.3% and 4.2% were homozygous, heterozygous and homozygous for the Arg72, Arg72Pro and the Pro72 polymorphism, respectively, whereas for controls, the distribution was 22.4%, 65.4% and 12.2%, respectively (P=0.00052), and among Ashkenazi breast cancer cases, allele distribution was 68.5%, 29.6% and 1.9%, whereas for controls, the distribution was 50%, 40% and 10%, respectively (P=0.0125). We conclude that arginine homozygosity at codon 72 of the p53 gene is associated with a significant increased breast cancer risk in Jewish high-risk population.     

P53 expression in human small-intestinal tumors

Expression of the tumor supressor gene product p53 in thirteen human small intestinal tumors was examined employing an immunohistochemical technique. The level of p53 was analysed using the monoclonal antibody pAb240. Six out of thirteen tumors (46%) including one lymphoma, one angiosarcoma of the jejunum, one leiomyosarcoma, one adenocarcinoma of the small intestine and two metastatic adenocarcinomas of the colon were found to have p53 overexpression. This is the first demonstration of p53 expression in small intestinal tumors. These results indicate that the p53 gene may be involved in the pathogenesis of small intestinal tumors.