p53 and P-glycoprotein are often co-expressed and are associated with poor prognosis in breast cancer.

Expression of both P-glycoprotein (P-gp) and mutant p53 have recently been reported to be associated with poor prognosis of breast cancer. The expression of P-gp is associated in vitro and in vivo with cross-resistance to several anti-cancer drugs. p53 plays a regulatory role in apoptosis, and mutant p53 has been suggested to be involved in drug resistance. Interestingly, in vitro experiments have shown that mutant p53 can activate the promoter of the MDR1 gene, which encodes P-gp. We investigated whether p53 and P-gp are simultaneously expressed in primary breast cancer cells and analysed the impact of the co-expression on patients prognosis. Immunohistochemistry was used to investigate P-gp expression (JSB-1, C219) and nuclear p53 accumulation (DO-7) in 20 operable chemotherapy untreated and 30 locally advanced breast cancers undergoing neoadjuvant chemotherapy with doxorubicin and cyclophosphamide. Double immunostaining showed that P-gp expression and nuclear p53 accumulation often occur concomitantly in the same tumour cells. A correlation between p53 and P-gp expression was found in all 50 breast cancers (P = 0.003; Fisher''s exact test). P-gp expression, nuclear p53 accumulation, and co-expression of p53 and P-gp were more frequently observed in locally advanced breast cancers than in operable breast cancers (P = 0.0004, P = 0.048; P = 0.002 respectively. Fisher''s exact test). Co-expression of p53 and P-gp was the strongest prognostic factor for shorter survival by multivariate analysis (P = 0.004) in the group of locally advanced breast cancers (univariate analysis: P = 0.0007). Only 3 out of 13 samples sequentially taken before and after chemotherapy displayed a change in P-gp or p53 staining. In conclusion, nuclear p53 accumulation is often associated with P-gp expression in primary breast cancer, and simultaneous expression of p53 and P-gp is associated with shorter survival in locally advanced breast cancer patients. Co-expression of P-gp and mutant p53 belong to a series of molecular events resulting in a more aggressive phenotype, drug resistance and poor prognosis.     

Methylation associated inactivation of RASSF1A from region 3p21.3 in lung, breast and ovarian tumours

Previously we analysed overlapping homozygous deletions in lung and breast tumours/tumour lines and defined a small region of 120 kb (part of LCTSGR1) at 3p21.3 that contained putative lung and breast cancer tumour suppressor gene(s) (TSG). Eight genes including RASSF1 were isolated from the minimal region. However, extensive mutation analysis in lung tumours and tumour lines revealed only rare inactivating mutations. Recently, de novo methylation at a CpG island associated with isoform A of RASSF1 (RASSF1A) was reported in lung tumours and tumour lines. To investigate RASSF1A as a candidate TSG for various cancers, we investigated: (a) RASSF1A methylation status in a large series of primary tumour and tumour lines; (b) chromosome 3p allele loss in lung tumours and (c) RASSF1 mutation analysis in breast tumours. RASSF1A promoter region CpG island methylation was detected in 72% of SCLC, 34% of NSCLC, 9% of breast, 10% of ovarian and 0% of primary cervical tumours and in 72% SCLC, 36% NSCLC, 80% of breast and 40% of ovarian tumour lines. In view of the lower frequency of RASSF1 methylation in primary breast cancers we proceeded to RASSF1 mutation analysis in 40 breast cancers. No mutations were detected, but six single nucleotide polymorphisms were identified. Twenty of 26 SCLC tumours with 3p21.3 allelic loss had RASSF1A methylation, while only six out of 22 NSCLC with 3p21.3 allele loss had RASSF1A methylation (P=0.0012), one out of five ovarian and none out of six cervical tumours with 3p21.3 loss had RASSF1A methylation. These results suggest that (a) RASSF1A inactivation by two hits (methylation and loss) is a critical step in SCLC tumourigenesis and (b) RASSF1A inactivation is of lesser importance in NSCLC, breast, ovarian and cervical cancers in which other genes within LCTSGR1 are likely to be implicated.     

High-resolution analysis of 16q22.1 in breast carcinoma using DNA amplifiable probes (multiplex amplifiable probe hybridization technique) and immunohistochemistry

Loss of the chromosomal material at 16q22.1 is one of the most frequent genetic aberrations found in both lobular and low-grade nonlobular invasive carcinoma of the breast, indicating the presence of a tumour suppressor gene (TSG) at this region in these tumours. However, the TSG (s) at the 16q22.1 in the more frequent nonlobular carcinomas is still unknown. Multiplex Amplifiable Probe Hybridisation (MAPH) is a simple, accurate and a high-resolution technique that provides an alternative approach to DNA copy-number measurement. The aim of our study was to examine the most likely candidate genes at 16q22.1 using MAPH assay combined with protein expression analysis by immunohistochemistry. We identified deletion at 16q22.1 that involves some or all of these genes. We also noticed that the smallest region of deletion at 16q22.1 could be delineated to a 3 Mb region centromeric to the P-cadherin gene. Apart from the correlation between E-cadherin protein expression and its gene copy number, no correlation was detected between the expression of E2F-4, CTCF, TRF2 or P-cadherin with their gene's copy number. In the malignant tissues, no significant loss or decrease of protein expression of any gene other than E-cadherin was seen in association with any specific tumour type. No expression of VE-cadherin or Ksp-cadherin was detected in the normal and/or malignant tissues of the breast in these cases. However, there was a correlation between increased nuclear expression of E2F-4 and tumours with higher histological grade (p = 0.04) and positive lymph node disease (p = 0.02), suggesting that it may have an oncogenic rather than a tumour suppressor role. The malignant breast tissues also showed abnormal cytoplasmic cellular localisation of CTCF, compared to its expression in the normal parenchymal cells. In conclusion, we have demonstrated that MAPH is a potential technique for assessment of genomic imbalances in malignant tissues. Although our results support E-cadherin as the TSG in invasive lobular carcinoma, they argue against the candidacy of E2F-4, CTCF, TRF2, P-cadherin, Ksp-cadherin and VE-cadherin as TSGs in breast cancer.     

Prognostic importance of survivin in breast cancer

Survivin is a member of the inhibitor of apoptosis (IAP) family, and is also involved in the regulation of cell division. Survivin is widely expressed in foetal tissues and in human cancers, but generally not in normal adult tissue. This study examined the expression of surviving protein in a series of 293 cases of invasive primary breast carcinoma. Survivin immunoreactivity was assessed using two different polyclonal antibodies, and evaluated semiquantitatively according to the percentage of cells demonstrating distinct nuclear and/or diffuse cytoplasmic staining. Overall, 60% of tumours were positive for survivin: 31% demonstrated nuclear staining only, 13% cytoplasmic only, and 16% of tumour cells demonstrated both nuclear and cytoplasmic staining. Statistical analysis revealed that survivin expression was independent of patient's age, tumour size, histological grade, nodal status, and oestrogen receptor status. In multivariate analysis, nuclear survivin expression was a significant independent prognostic indicator of favourable outcome both in relapse-free and overall survival (P<0.001 and P=0.01, respectively). In conclusion, our results show that survivin is frequently overexpressed in primary breast cancer. Nuclear expression is most common and is an independent prognostic indicator of good prognosis.     

Jun activation domain binding protein 1 expression is associated with low p27(Kip1)levels in node-negative breast cancer.

PURPOSE: The purpose is to evaluate expression levels of Jun activation domain-binding protein 1 (JAB1) in breast cancer tissue and adjacent normal tissue, to determine whether JAB1 expression is associated with p27(Kip1) expression in invasive breast carcinomas, and to evaluate the prognostic significance of JAB1 and p27(Kip1) in node-negative breast cancer. EXPERIMENTAL DESIGN: JAB1 levels were measured in 10 matched pairs of invasive breast tumor tissue and adjacent normal tissue using Western blot analysis. We also investigated the immunoreactivity of JAB1 and p27(Kip1) levels in paraffin-embedded tissue specimens from 220 patients with node-negative breast cancer who had not received adjuvant systemic therapy. The median follow-up was 15 years. RESULTS: JAB1 was expressed at higher levels in invasive tumors than in adjacent normal tissue (P = 0.01). JAB1 overexpression was observed in 57% of invasive breast cancers. Low levels of p27(Kip1) were noted in 70% of the tumor specimens. We found an inverse correlation between JAB1 and p27(Kip1) expression levels (P = 0.01). JAB1 overexpression was associated with patient age of at least 50 years (P = 0.03) and tumor size of 相似文献   

ATM expression in rectal cancers with or without preoperative radiotherapy

Patients with ATM (Ataxia-Telangiectasia mutated) mutation show increased sensitivity to radiation and have a higher risk of developing malignancies. The present study aimed to investigate whether ATM expression was related to radiotherapy, and clinicopathological and biological variables in rectal cancers. ATM expression was immunohistochemically examined in 78 rectal cancers from patients who participated in a Swedish rectal cancer trial of preoperative radiotherapy. Of 78 patients, 44 underwent surgery alone, and 34 underwent both preoperative radiotherapy and surgery. Fifty-eight cases had normal rectal mucosa adjacent to the tumour. The results showed that, compared to normal mucosa, tumours had less nuclear (p=0.03) but more cytoplasmic expression of ATM (p=0.004). In tumours, less expression of ATM, either in the nucleus (p=0.07) or in the cytoplasm (p=0.02 for staining intensity, and p=0.07 for staining percentage), tended to be correlated with male patients. Also, ATM expression was not related to radiotherapy or other clinicopathological and biological variables (p>0.05). In conclusion, the pattern of ATM expression was changed from normal mucosa to tumour. Less expression of ATM may be related to males.     

Prognostic value of nuclear survivin expression in oesophageal squamous cell carcinoma

Survivin, a new member of the family of apoptosis inhibitors, is expressed almost exclusively in proliferating cells, above all in cancers. Subcellular localisation and prognostic implications of the survivin protein have not yet been determined in oesophageal squamous cell carcinoma. The survival of 84 patients with oesophageal squamous cell carcinomas was correlated with the extent of immunohistochemical survivin expression in tumour cell nuclei. Tumours were scored positive when >5% cells stained positive. Patients were followed up for at least 5 years or until death. In normal oesophageal squamous cell epithelium, some cytoplasmic survivin expression was detected in the basal cells, whereas proliferating cells showed nuclear staining of survivin. Nuclear expression of survivin was also detected in 67 cancers (80%). The mean survival for patients of this group (28 months, range 20-36) was significantly less than that for patients without survivin expression in the tumour cell nuclei (108 months, range 62-154, P=0.003). Using univariate analysis, nuclear survivin expression (P=0.003), tumour depth (P=0.001), lymph node metastasis (P=0.003) and stage (P<0.001) were the best predictors of survival. In contrast, cytoplasmic survivin staining was noted in 53 (63%) tumours and had no prognostic relevance. In conclusion, the analysis of nuclear survivin expression identifies subgroups in oesophageal squamous cell cancer with favourable (survivin(-)) or with poor prognosis (survivin(+)). We suggest that the determination of nuclear survivin expression could be used to individualise therapeutic strategies in oesophageal squamous cell cancer in the future.     

Leptin and leptin receptor involvement in cancer development: a study on human primary breast carcinoma

Obesity is associated with an increased risk of breast cancer. Leptin, a hormone synthesised essentially by adipose tissue, may be involved in cancer development. We examined the expression of leptin and leptin receptor (Ob-R) in human primary breast cancer and adjacent non-cancerous tissue. We also analysed their relationships with histological variables such as the oestrogen and progesterone receptors, Ki67 proliferation factor and tumour size. The expressions of leptin and Ob-R were investigated by immunohistochemical staining in 35 primary breast cancers and 17 adjacent non-cancerous tissues. Samples and histological features were obtained from the Anti-Cancer Centre. Expressions of leptin and Ob-R were detected in, respectively, 85 and 75% of the primary breast cancer cases studied. The expression of leptin was significantly correlated with Ob-R detection (p=0.008). In addition, Ob-R expression in primary breast carcinoma was positively correlated with oestrogen receptor expression (p=0.028) and tumour size (p=0.045) but not with Ki67 or progesterone receptor expressions. However, the expression of leptin showed no statistical correlation with these variables. First, the co-expression of leptin and Ob-R in primary breast cancer shows that leptin acts on mammary tumour cells via an autocrine pathway. Second, the co-expression of Ob-R and oestrogen receptors suggests a possible interaction between leptin and oestrogen systems to promote breast carcinogenesis. Finally, the fact that Ob-R expression was positively correlated with tumour size may point to a potential role of leptin as a growth factor and of Ob-R as a new prognostic factor.     

Expression of the p65 gene in patients with colorectal cancer: comparison with some histological typing, grading and clinical staging.

AIMS: P65 protein/gene is a potential, non-specific tumour marker expressed by different types of neoplasms. In this study p65 gene expression was estimated in a group of colorectal cancers and compared with some histological features, grading and clinical staging of the neoplasms to assess its role as a prognostic marker for colorectal cancer. METHODS: 109 pairs of frozen samples of colorectal carcinomas and adjacent normal colorectal mucosa and four samples of tissue from patients without neoplastic diseases were analysed by means of RT-PCR. RESULTS: Expression of p65 gene was found in 51 out of 109 cases of colorectal cancers. For 19 of them expression of examined gene was observed both in cancer and corresponding healthy mucosa. p65 Gene expression was associated with more advanced tumours (T3, T4; p=0.0003) with metastases to lymph nodes (N1, N2; p=0.0003) and distant metastases (p=0.0005). We did not find association between the age, gender, tumour localization, histological type and p65 gene expression. CONCLUSIONS: p65 Gene expression in primary tumour tissue is associated with poor prognosis for the patients with colorectal cancer in this series.     

p21 is associated with cyclin D1, p16INK4a and pRb expression in resectable non-small cell lung cancer

p21 (p21WAF1/CIP1) is involved in cell cycle regulation, as an inhibitor of cyclin dependent kinases (CDK2, CDK4 and CDK6). However, subsequent in vitro studies have suggested that p21 may influence this process by an additional mechanism, in particular through the regulation of cyclin D1 subcellular localisation. This study of primary resectable non-small cell lung cancer (NSCLC) was designed to examine p21 functions in association with the expression of cyclin D1 (including its subcellular localisation), p16INK4a and pRb. p21 expression was examined in 50 NSCLC (stage I-IIIA) and in several normal lung samples all of which had previously been studied for cyclin D1 (DNA, RT-PCR, immunostaining), p16INK4a (DNA, RT-PCR, immunostaining), and pRb (immunostaining). As assessed by immunoblotting and immunostaining, p21 was expressed at low levels in normal lung tissue with immunoreactivity seen in a small number of bronchial epithelial cells only. In NSCLC, p21 expression (> or =10% of positive cells) was observed in 42% (21/50) of cases. High p21 expression was associated with well differentiated tumours (p = 0.01) and cyclin D1 nuclear staining (p = 0.02). Furthermore, we found an inverse correlation with p16INK4a (p = 0.004) and a direct correlation with pRb expression (p = 0.02). Risk of relapse was associated with p16INK4a and p21 status with no relapse in patients with normal p16INK4a and p21. Our results confirm that a large number of NSCLC have a low level of p21 expression. The associations of p21 and nuclear cyclin D1, pRb, p16INK4a support the relevance of pathways linked to lung carcinogenesis that involve p21 but may act in addition to direct CDK inhibition.     

Nuclear expression of the c-erbB-4/HER-4 growth factor receptor in invasive breast cancers

The prevalence and sites of expression of the c-erbB-4 receptor have been determined by immunocytochemical staining in a series of 178 human breast cancers. Most tumors displayed cytoplasmic staining of variable intensity. When compared with adjacent normal tissue, 32 cases (18%) showed lower than normal expression, and 13 (7%) showed greater than normal expression. Nuclear immunoreactivity, confirmed by two different antibodies, was present in 87 cancers (49%) but was found in normal adjacent breast epithelial cells in <5% of cases. There were no significant associations with cytoplasmic or membrane immunoreactivity, but cases showing nuclear expression in >25% of cells were associated with good histological grade, epidermal growth factor receptor expression, c-erbB-3 positivity, cripto, amphiregulin, and transforming growth factor-alpha overexpression.     

LIMD2蛋白及E钙黏素在非小细胞肺癌中的表达及其临床意义

目的:探讨含LIM域2（LIM domain containing 2,LIMD2)蛋白及E钙黏素（E-cadherin）在非小细胞肺癌(NSCLC)中的表达及临床意义。方法:采用免疫组化法对141例NSCLC肿瘤组织和25例癌旁组织中的LIMD2蛋白及E钙黏素进行检测。SPSS 21进行统计学分析,P＜0.05认为差异有统计学意义。结果:LIMD2在肿瘤组织中高表达71例（50.4%）,低表达70例（49.6%）;在癌旁组织中高表达7例（28.0%）,低表达18例（72.0%）,LIMD2在肿瘤组织中高表达较癌旁组织常见。E钙黏素在肿瘤组织中高表达75例（53.2%）,低表达66例（46.8%）;在癌旁组织中高表达13例（52.0%）,低表达12例（48.0%）,E钙黏素在两种组织中表达无差异。肿瘤组织中LIMD2表达水平在不同N分期、TNM分期及肿瘤分化程度方面存在差异,LIMD2高表达常见于术后无病生存期（DFS）短的患者中（P=0.033）。E钙黏素表达水平在不同的T分期、N分期及TNM分期中存在差异,E钙黏素高表达在术后DFS较长的患者中常见（P=0.000）。在癌组织中LIMD2表达水平与E钙黏素表达水平呈负相关（P=0.000）。多因素回归分析表明性别、T分期、TNM分期、肿瘤分化程度、LIMD2及E钙黏素表达与NSCLC术后DFS相关。结论:在NSCLC中LIMD2与E钙黏素表达呈负相关,LIMD2在肿瘤组织中表达越高术后DFS越短,LIMD2或许可以作为预测NSCLC术后复发的生物标志物。     

KAI1/CD82 is a novel target of estrogen receptor-mediated gene repression and downregulated in primary human breast cancer

The cell-surface glycoprotein KAI1 suppresses tumor growth and metastasis in various animal models. Downregulation of KAI1 has been implicated in the progression of cancer. However, the mechanisms of KAI1 inactivation are poorly understood. This is the first study that investigates expression and regulation of KAI1 in human breast cancer. KAI1 expression was analyzed on custom-made tissue microarrays comprising 209 well-characterized breast cancers and normal mammary gland tissue. Strong KAI1 immunoreactivity was observed throughout the normal mammary gland epithelium. In breast cancer tissue, KAI1 immunoreactivity was lost in 161/209 (77%) cases. Strikingly, KAI1 was preferentially lost in estrogen receptor (ER)-positive breast cancers (p < 0.001). This was validated by real-time RT-PCR analyses showing a 7.5-fold downregulation of KAI1 mRNA in ER-positive relative to ER-negative tumors (p = 0.028). Notably, this was also corroborated by Affymetrix microarray expression data of an independent cohort of 49 breast cancers. Class comparison analysis identified KAI1 as downregulated in ER-positive tumors. Subsequently, human breast cancer cell lines were employed to test a potential role of ER-activity in the downregulation of KAI1, as suggested by our expression analyses. Exposure of ER-positive breast cancer cells to fulvestrant, a clinically approved ER-antagonist that reverses ER-mediated gene repression, induced a significant upregulation of KAI1 and inhibited cell proliferation as well as migration. In summary, we demonstrate for the first time that KAI1 is a target of ER-mediated gene-repression, and thus, it is downregulated in ER-positive breast cancer. Importantly, KAI1 might be reinducible by endocrine therapy with ER-antagonists in patients suffering from ER-positive breast cancer.     

Expression and mutation analysis of the discoidin domain receptors 1 and 2 in non-small cell lung carcinoma

The discoidin domain receptors, (DDR)1 and DDR2, have been linked to numerous human cancers. We sought to determine expression levels of DDRs in human lung cancer, investigate prognostic determinates, and determine the prevalence of recently reported mutations in these receptor tyrosine kinases. Tumour samples from 146 non-small cell lung carcinoma (NSCLC) patients were analysed for relative expression of DDR1 and DDR2 using quantitative real-time PCR (qRT-PCR). An additional 23 matched tumour and normal tissues were tested for differential expression of DDR1 and DDR2, and previously reported somatic mutations. Discoidin domain receptor 1 was found to be significantly upregulated by 2.15-fold (P=0.0005) and DDR2 significantly downregulated to an equivalent extent (P=0.0001) in tumour vs normal lung tissue. Discoidin domain receptor 2 expression was not predictive for patient survival; however, DDR1 expression was significantly associated with overall (hazard ratio (HR) 0.43, 95% CI=0.22-0.83, P=0.014) and disease-free survival (HR=0.56, 95% CI=0.33-0.94, P=0.029). Multivariate analysis revealed DDR1 is an independent favourable predictor for prognosis independent of tumour differentiation, stage, histology, and patient age. However, contrary to previous work, we did not observe DDR mutations. We conclude that whereas altered expression of DDRs may contribute to malignant progression of NSCLC, it is unlikely that this results from mutations in the DDR1 and DDR2 genes that we investigated.     

A role for BRCA1 in sporadic breast cancer

To test the hypothesis that altered expression of BRCA1 protein may play an important role in sporadic breast cancer development, 50 randomly selected primary breast cancers (frozen sections, 5 years' median follow-up) were immunolabelled with two monoclonal BRCA1 antibodies (MS110 and MS13). MS110 labelling was exclusively nuclear showing no relation to outcome or tumour pathology. Western blotting demonstrated crossreactivity, suggesting antibody nonspecificity. MS13 labelling was predominantly cytoplasmic. Intense labelling predicted decreased overall survival (P=0.012), disease-free survival (P=0.029), oestrogen receptor negativity (P=0.0004) and c-erbB-2 overexpression (P=0.006). Western blotting detected a 110 kDa molecule consistent with BRCA1 delta11b splice variant. BRCA1 protein is postulated to function as a tumour suppressor. We demonstrate cytoplasmic localisation in sporadic breast cancer suggesting excess delta11b splice variant production, reduced production of full-length BRCA1 and thus postulate reduced tumour suppressor activity. BRCA1 protein appears to have a significant role in both sporadic and hereditary breast cancers.