<Emphasis Type="Italic">CCND1</Emphasis> amplification and cyclin D1 expression in breast cancer and their relation with proteomic subgroups and patient outcome

INTRODUCTION: Despite strong evidence regarding the role of CCND1 amplification and protein overexpression in breast carcinoma, the associations between CCND1 amplification/cyclin D1 overexpression and clinicopathological variables and clinical outcome remain controversial. AIMS OF THE STUDY: (1) to correlate cyclin D1 expression with gene amplification; (2) to analyse the correlations between CCND1 amplification and overexpression with clinicopathological features and patients' outcome in invasive breast cancer; (3) to define the prevalence and clinical significance of cyclin D1 overexpression and CCND1 amplification in ER positive breast carcinomas (4) to define the prevalence of cyclin D1 overexpression and CCND1 amplification in breast cancers with basal-like immunophenotype. MATERIALS AND METHODS: CCND1 amplification and protein expression were assessed on a tissue microarray containing 880 unselected invasive breast cancer cases, by means of chromogenic in situ hybridisation using the Spotlight CCND1 amplification probe and immunohistochemistry, using the rabbit monoclonal antibody SP4. RESULTS: A total of 59/613 tumours (9.6%) showed CCND1 amplification and 224/514 (43.6%) showed strong cyclin D1 expression. A strong positive correlation between CCND1 amplification and higher levels of cyclin D1 expression was found (P < 0.001). Basal-like cancers showed infrequent CCND1 amplification and cyclin D1 overexpression (P < 0.001). Both CCND1 amplification and cyclin D1 expression were associated with positive ER status. CCND1 gene amplification was an independent prognostic factor for patients with ER positive breast cancer. CONCLUSION: Our results demonstrate a strong correlation between CCND1 amplification and its protein expression in breast cancer. However, protein expression is more pervasive than gene amplification and associated with ER expression.     

乳腺癌组织中E-cadherin、β-catenin及cyclin D1表达的相关性研究

背景与目的上皮性钙粘素(E-cadherin)通过连接素(catenins)与细胞骨架相连介导细胞同质粘附反应,β-catenin除与E-cadherin结合介导细胞粘附反应外,还作为Wnt信号转导通路的重要成分与肿瘤发生密切相关。本研究通过检测乳腺癌组织中E-cadherin、β-catenin及cyclinD1的表达,探讨E-cadherin、β-catenin在乳腺癌发生、发展中的意义。方法采用免疫组织化学SP法检测60例乳腺癌组织中E-cadherin、β-catenin、cyclinD1的表达。结果乳腺癌组织中有29例(48.3%)E-cadherin、18例(30.0%)β-catenin正常表达,28例(46.7%)cyclinD1过度表达。E-cadherin正常表达病例中,31.0%(9/29)的病例呈现cyclinD1过度表达,而E-cadherin异常表达病例中,61.3%(19/31)的病例呈现cyclinD1过度表达,E-cadherin异常表达与cyclinD1的过度表达有显著的正相关性(rs=0.303,P<0.05)。有42例癌组织表现出β-catenin的异常表达,其中57.1%(24/42)的病例出现cyclinD1的过度表达,而β-catenin正常膜表达病例中,22.2%(4/18)的病例呈现cyclinD1的过度表达。β-catenin的异常表达与cyclinD1的过度表达有显著的正相关性(rs=0.321,P<0.05)。结论E-cadherin和β-catenin的异常表达可能通过促使或激活cyclinD1的过度表达导致乳腺癌的发生和发展。     

Cyclin D1 overexpression is not a specific grouping marker, but may collaborate with CDC37 in myeloma cells

Cyclin D1 is a positive-regulator of the cell cycle and is overexpressed in myeloma cells with t(11;14)(q13;q32). First, we analyzed whether there was a correlation between cyclin D1 overexpression and the presence of Ki67-positive myeloma cells in multiple myeloma (MM). Cyclin D1 overexpression was examined by competitive RT-PCR. Then we found these two markers were present independently in a given case. FISH analysis revealed that cyclin D1 over-expression was caused by t(11;14)(q13;q32) or extra copies of B-cell leukemia/lymphoma-1 (BCL-1/CCND1), and unknown mechanism without them. We compared the gene expression between myeloma cells with cyclin D1 overexpression and those without it using cDNA microarray analysis. Analysis of the expression profiles showed that the significantly up-regulated genes included cyclin D1, cell division cycle 37 (CDC37) and B-cell leukemia/lymphoma-2 (BCL-2), while the down-regulated genes included cyclin D2 and CD9 antigen (p24) in MM cases with cyclin D1 overexpression. However, hierarchical clustering analysis of the data showed that myeloma cells of MM cases with cyclin D1 overexpression could not be distinguished clearly from those without it. Real-time RT-PCR showed that the expression of CDC37 gene was significantly up-regulated in MM patients with cyclin D1 overexpression compared with those without it (p=0.0418). However, there was no significant difference in BCL-2 gene (p=0.5748). These results suggested that MM cases with cyclin D1 overexpression do not constitute a specific group, and cyclin D1 overexpression may not be caused only by abnormality of the BCL-1/CCND1 gene. The CDC37 may collaborate with cyclin D1 in progression of MM.     

Cyclin D1 overexpression is more prevalent in non-Caucasian breast cancer

African-American women with breast cancer consistently show a shortened survival when compared with Caucasians with breast cancer, however it is not clear whether this is due to socioeconomic factors or to racial differences in tumor biology. Cyclin D1 overexpression has been demonstrated in 60-80% of female breast cancers, however these studies have not included race or ethnicity data. We examined the level of cyclin D1 protein expression in 139 cases of female breast cancer obtained from different ethnic populations. Using an immunoperoxidase-based technique and a polyclonal anti-cyclin D1 antibody, the rate of overexpression was 68%. Cyclin D1 overexpression tended to be more frequent in cases from non-Caucasian patients when compared with those from Caucasian patients (77% vs. 59%, p=0.051). Our findings suggest that non-Caucasian ethnicity may be important in predicting cyclin D1 overexpression. Cyclin D1 could therefore serve as a possible target in managing breast cancer in the African-American population.     

High CCND1 amplification identifies a group of poor prognosis women with estrogen receptor positive breast cancer

CCND1 encodes for the cyclin D1 protein involved in G1/S cell cycle transition. In breast cancer the mechanism of CCND1 amplification, relationship between cyclin D1 protein expression and the key clinical markers estrogen receptor (ER) and HER2 requires elucidation. Tissue microarrays of primary invasive breast cancer from 93 women were evaluated for CCND1 amplification by fluorescent in‐situ hybridization and cyclin D1 protein overexpression by immunohistochemistry. CCND1 amplification was identified in 27/93 (30%) cancers and 59/93 (63%) cancers had overexpression of cyclin D1. CCND1 amplification was significantly associated with cyclin D1 protein overexpression (p < 0.001; Fisher's exact test) and both CCND1 amplification and cyclin D1 protein expression with oestrogen receptor (ER) expression (p = 0.003 and p < 0.001; Fishers exact test). Neither CCND1 amplification nor cyclinD1 expression was associated with tumor size, pathological node status or HER2 amplification, but high CCND1 amplification (Copy Number Gain (CNG) ≥ 8) was associated with high tumor grade (p = 0.005; chi square 7.915, 2 df) and worse prognosis by Nottingham Prognostic Index (p = 0.001; 2 sample t‐test). High CCND1 amplification (CNG ≥ 8) may identify a subset of patients with poor prognosis ER‐positive breast cancers who should be considered for additional therapy.     

Effects of cyclin D1 gene amplification and protein expression on time to recurrence in postmenopausal breast cancer patients treated with anastrozole or tamoxifen: a TransATAC study

INTRODUCTION: Gene amplification of CCND1 is observed in a subgroup of breast cancers with poor prognosis, whereas overexpression of the protein cyclin D1 has been linked to both worse and better clinical outcome. CCND1 amplification and protein overexpression have also been associated with resistance to treatment with tamoxifen or even to a potentially detrimental effect of tamoxifen. METHODS: To clarify these challenging and partly contrasting treatment predictive and prognostic links for cyclin D1 we analysed a large cohort of postmenopausal breast cancer patients randomised to receive either adjuvant anastrozole or tamoxifen, as part of the Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial. The CCND1 amplification status and protein expression of cyclin D1 were assessed by chromogenic in situ hybridisation and immunohistochemistry, respectively, in 1,155 postmenopausal, oestrogen-receptor-positive breast cancer patients included in the TransATAC substudy. RESULTS: Amplification of CCND1 was observed in 8.7% of the tumours and was associated with increased risk of disease recurrence (hazard ratio = 1.61; 95% confidence interval, 1.08 to 2.41) after adjustment for other clinicopathological parameters. In contrast, nuclear expression of cyclin D1 protein was associated with decreased recurrence rate (hazard ratio = 0.6; 95% confidence interval, 0.39 to 0.92). The intensity of nuclear or cytoplasmic expression was not of prognostic value. There was no significant interaction between cyclin D1 status and treatment efficacy, ruling out any major detrimental effect of tamoxifen in CCND1-amplified postmenopausal breast cancer. CONCLUSIONS: In summary, CCND1 amplification and low nuclear expression of cyclin D1 predicted poor clinical outcome in postmenopausal breast cancer patients treated with either anastrozole or tamoxifen. TRIAL REGISTRATION: Current Controlled Trials ISRCTN18233230.     

High Pin1 expression is associated with tumor progression in colorectal cancer

BACKGROUND AND OBJECTIVES: Peptidyl prolyl cis-trans isomerase (Pin1) isomerizes only phosphorylated serine or threonine residues preceding proline in certain proteins and affects the protein function. Pin1 interacts with many signaling pathways, including Wnt signaling pathway that is crucial for colorectal tumorigenesis. Pin1 promotes cyclin D1 over-expression directly or through the stabilization of beta-catenin. Pin1 is over-expressed in some cancers such as prostate and breast cancers. This study aimed to determine whether Pin1 plays a role in colorectal tumorigenesis through the upregulation of beta-catenin and cyclin D1. METHODS: Immunohistochemical analyses were performed on 105 colorectal cancer tissue samples using anti-Pin1, anti-beta-catenin, and anti-cyclin D1 antibodies. We examined the relationships between Pin1 expression and clinicopathological factors, prognosis, and beta-catenin/cyclin D1 expression. RESULTS: High Pin1 expression was observed in 40 cases (38%) and positively correlated with histological type (P=0.0240), depth of invasion (P=0.0051), and staging (P=0.0027) of colorectal tumors. High Pin1 expression was also correlated with the over-expressions of both beta-catenin (P=0.0225) and cyclin D1 (P=0.0137). CONCLUSIONS: These results suggest that Pin1 plays an important role in colorectal tumorigenesis, presumably by increasing beta-catenin and cyclin D1 expressions.     

Examining the role of cyclin D1 in breast cancer

Cyclin D1 overexpression is found in more than 50% of human breast cancers and causes mammary cancer in transgenic mice. Dysregulation of cyclin D1 gene expression or function contributes to the loss of normal cell cycle control during tumorigenesis. Recent studies have demonstrated that cyclin D1 conducts additional specific functions to regulate gene expression in the context of local chromatin, promote cellular migration and inhibit mitochondrial metabolism. It is anticipated that these additional functions contribute to the pathology associated with dysregulated cyclin D1 abundance. This article discusses evidence that examines the significance of cyclin D1 in breast cancer with emphasis on its role in breast cancer stem cell expansion.     

Cyclin D1 protein overexpression and gene amplification in benign breast tissue and breast cancer risk.

Cyclin D1 amplification and/or protein overexpression have been observed not only in breast cancer but also in the putative early stages of breast neoplasia. In a case-control study nested within a cohort of 4888 women, we investigated whether the occurrence of cyclin D1 gene amplification and/or protein overexpression in benign breast tissue might identify women at increased risk of subsequent breast cancer development. Cases were 92 women with a histological diagnosis of benign breast disease who subsequently developed breast cancer. Five controls (women with benign breast disease who had not developed breast cancer by the date of diagnosis of the corresponding case) were selected randomly for each case from those non-cases available within strata defined by screening centre, National Breast Screening Study (NBSS) study arm, year of birth and age at diagnosis of benign breast disease. Paraffin blocks of benign tissue were suitable for immunostaining for 71 cases and 293 controls. Sufficient DNA for analysis was obtained from a total of 356 subjects (69 cases, 287 controls). The benign breast tissues and breast cancers were immunostained for cyclin D1 and also analysed for the presence of cyclin D1 gene amplification by differential polymerase chain reaction (PCR). Fifteen cases and 60 controls showed evidence of cyclin D1 immunostaining, and 12 cases and 29 controls showed cyclin DL gene amplification. There was essentially no association between cyclin D1 protein overexpression in benign breast tissue and risk of subsequent breast cancer (adjusted odds ratio (OR) 1.06; 95% confidence interval (CI) 0.56-2.02). After adjustment for potential confounding, there was a statistically non-significant 40% increase in risk of breast cancer in association with cyclin D1 gene amplification (adjusted OR 1.41; 95% CI 0.62-3.22). As multiple genetic changes are required to develop breast cancer, it may not be until the cascade of molecular alterations leading to breast cancer development is understood that identification of biomarkers of breast cancer risk will be possible.     

Cyclin D1 overexpression as a prognostic factor in patients with esophageal carcinoma.

BACKGROUND AND OBJECTIVES: Cyclin D1 is known to play important roles in the G1/S check-point of the cell cycle. We investigated the correlation between cyclin D1 overexpression and clinical characteristics to clarify its prognostic significance in patients with esophageal cancer. METHODS: From 1991 to 1998, cyclin D1 was investigated in esophageal cancers from 86 patients who underwent esophagectomy. Overexpression of cyclin D1 was demonstrated using an immunohistochemical method. RESULTS: Overexpression of cyclin D1 was found in 23 (26.7%) of 86 cases. Overexpression of cyclin D1 correlated with lymph node metastasis (P = 0.0083) and lymphatic vessel invasion (P = 0.018). Cyclin D1 overexpression may indicate resistance to chemotherapy. The patients with cyclin D1 overexpression had a significantly lower survival rate than those without overexpression (P = 0.013). The multivariate analysis revealed cyclin D1 overexpression to be an important prognostic factor in patients with esophageal cancer. CONCLUSIONS: Immunohistochemical examination of cyclin D1 expression may provide important prognostic information in univariate and multivariate analysis and may be necessary for determining therapeutic strategies for esophageal cancer.     

Role of COX-2, VEGF and cyclin D1 in mammary infiltrating duct carcinoma

Cyclooxygenase-2 (COX-2) has an important role in the promotion of carcinogenesis, tumor invasion and angiogenesis. Vascular endothelial growth factor (VEGF) is a proangiogenic factor that is up-regulated in various tumors. VEGF has been shown to interact with COX-derived prostaglandins in angiogenesis. Cyclin D1 gene overexpression and amplification have been shown to play a role as prognostic factors in many human cancers. To better understand the roles of these genes in mammary carcinoma, the immunohistochemical expression patterns of COX-2 and VEGF were evaluated in relationship with cyclin D1 overexpression, tumor stage, clinicopathologic parameters and patient survival in 128 mammary infiltrating duct carcinomas. The expressions of COX-2/VEGF, COX-2/cyclin D1, and VEGF/cyclin D1 were evaluated using double immunofluorescein staining with a confocal scanning laser microscope. A positive expression was seen in 41% for COX-2, 47% for VEGF, and 66% for cyclin D1 in the cases with breast cancer. There was correlation in positive expression of COX-2 or VEGF with histologic grade, lymph node metastasis, and tumor size. Conversely, a significant inverse relation was observed between VEGF and patient age. There was a correlation in overexpression of cyclin D1 with lymph node metastasis, survival rate and survival length. Significant correlations were observed between COX-2 and VEGF as well as COX-2 and cyclin D1. Co-expression of only COX-2 and VEGF was detected with significance. These results indicate that elevated COX-2 or VEGF expression or cyclin D1 overexpression is more common in breast cancer patients with poor prognostic characteristics and is partly associated with an unfavorable outcome. The present findings support the efforts to initiate clinical trials on the efficacy of COX-2 inhibitors in adjuvant treatment of breast cancer.     

Expression of c-erbB2, cyclin D1 and estrogen receptor and their clinical implications in the invasive ductal carcinoma of the breast

BACKGROUND: C-erbB2 and estrogen receptors (ER) are well known for their cell proliferative capacity. Cyclin D1 is a major downstream target of both c-erbB2 and ER. This study was designed to analyze the expression of c-erbB2, cyclin D1 and ER and their prognostic implications in invasive ductal carcinoma of the breast. METHODS: The c-erbB2 status was evaluated by fluorescence in situ hybridization and immunohistochemistry (IHC) and cyclin D1 and ER were evaluated by IHC in 333 invasive breast cancer specimens. RESULTS: The results of FISH and IHC for c-erbB2 showed 86.7% concordance. The overexpression of c-erbB2 was associated with the high expression of cyclin D1 and the negative expression of ER (P < 0.01 for both). The high expression of cyclin D1 was associated with the positive expression of ER (P < 0.01). When the group of patients who overexpressed c-erbB2 were analyzed, the patients with the low expression of cyclin D1 showed a significantly higher mortality than those with the high expression of cyclin D1 (RR = 3.2; 95% CI, 1.6-6.6). When the group of the high cyclin D1 expression was analyzed, the patients with negative expression of ER showed a significantly higher mortality than those with the positive expression of ER (RR = 2.1; 95% CI, 1.1-3.8). CONCLUSIONS: Higher expression of cyclin D1 was associated with better prognosis in patients with c-erbB2 overexpression, and positive expression of ER was associated with better prognosis in patients with high cyclin D1 expression.     

Knocking down cyclin D1b inhibits breast cancer cell growth and suppresses tumor development in a breast cancer model

Cyclin D1 is aberrantly expressed in many types of cancers, including breast cancer. High levels of cyclin D1b, the truncated isoform of cyclin D1, have been reported to be associated with a poor prognosis for breast cancer patients. In the present study, we used siRNA to target cyclin D1b overexpression and assessed its ability to suppress breast cancer growth in nude mice. Cyclin D1b siRNA effectively inhibited overexpression of cyclin D1b. Depletion of cyclin D1b promoted apoptosis of cyclin D1b-overexpressing cells and blocked their proliferation and transformation phenotypes. Notably, cyclin D1b overexpression is correlated with triple-negative basal-like breast cancers, which lack specific therapeutic targets. Administration of cyclin D1b siRNA inhibited breast tumor growth in nude mice and cyclin D1b siRNA synergistically enhanced the cell killing effects of doxorubicin in cell culture, with this combination significantly suppressing tumor growth in the mouse model. In conclusion, the results indicate that cyclin D1b, which is overexpressed in breast cancer, may serve as a novel and effective therapeutic target. More importantly, the present study clearly demonstrated a very promising therapeutic potential for cyclin D1b siRNA in the treatment of cyclin D1b-overexpressing breast cancers, including the very malignant triple-negative breast cancers.     

Constitutive overexpression of cyclin D1 but not cyclin E confers acute resistance to antiestrogens in T-47D breast cancer cells

Cyclin D1 and cyclin E are overexpressed in approximately 45% and 30% of breast cancers, respectively, and adverse associations with patient outcome have been reported. The potential roles of cyclin D1 and cyclin E expression as markers of therapeutic responsiveness to the pure steroidal antiestrogen ICI 182780 were investigated using T-47D breast cancer cell lines constitutively overexpressing cyclin D1 or cyclin E. Measurement of S phase fraction, phosphorylation states of the retinoblastoma protein, and cyclin E-cyclin-dependent kinase (Cdk) 2 activity demonstrated that overexpression of cyclin D1 decreased sensitivity to antiestrogen inhibition at 24 and 48 h. Overexpression of cyclin E produced a less pronounced early cell cycle effect indicating only partial resistance to antiestrogen inhibition in the short-term. In ICI 182780-treated cyclin D1-overexpressing cells, sufficient Cdk activity was retained to allow retinoblastoma protein phosphorylation and cell proliferation, despite an increase in the association of p21 and p27 with cyclin D1-Cdk4/6 and cyclin E-Cdk2 complexes. After longer-term (>7 days) treatment, antiestrogens inhibited colony growth in cyclin D1- or cyclin E-overexpressing breast cancer cells, but with an approximately 2-2.5-fold decrease in dose sensitivity. This was associated with a fall in cyclin D1 levels, a reduction in the half-life of cyclin D1 protein and a decline in cyclin E-Cdk2 activity in cyclin D1-overexpressing cells, and the maintenance of cyclin E-p27 association in the cyclin E-overexpressing cells. These data confirm that cyclin D1 expression and cyclin E-p27 association play important roles in antiestrogen action, and suggest that cyclin D1 or cyclin E overexpression has subtle effects on antiestrogen sensitivity. Additional studies to elucidate the contribution of alterations in cyclin D1 stability to antiestrogen action and to assess the relationship between antiestrogen sensitivity and expression of cyclin D1, cyclin E, or p27 in a clinical setting are required.     

A multi-institutional study of immunohistochemical investigation for the roles of cyclin D1 and E-cadherin in superficial squamous cell carcinoma of the esophagus

BACKGROUND AND OBJECTIVES: Aiming to clarify and possibly extend indications for minimally invasive treatment, we characterized superficial esophageal cancers (SEC) with respect to biologic properties regulating malignant potential. METHODS: Surgical specimens obtained at eight cancer institutes from 222 Japanese patients with SEC (all squamous cell carcinomas) were investigated immunohistochemically for expression of cyclin D1 and E-cadherin. RESULTS: Perturbations of cyclin D1 (overexpression) and E-cadherin (reduced expression) were observed in 37.6% (68 of 181) and 39.9% (71 of 178) of SEC patients. E-cadherin expression was more frequently reduced in cancers that invaded the submucosal layer, while cyclin D1 overexpression was constant, irrespective of depth of invasion. Overexpression of cyclin D1 was more frequent in poorly differentiated squamous cell carcinomas, while E-cadherin did not vary according to histologic differentiation. Lymph node metastasis, the only independent postoperative prognostic factor in these patients, occurred in only 4.8% of mucosal cancers (2 of 42), but in 51.1% of submucosal cancers (92 of 180). However, neither cyclin D1 nor E-cadherin status affected lymph node metastasis. CONCLUSION: Both E-cadherin and cyclin D1 play important roles in esophageal carcinogenesis, but neither can be used to identify patients who do not require lymph node dissection and might be treated by endoscopic mucosal resection.     

Role of cyclin D1 in ErbB2-positive breast cancer and tamoxifen resistance

Cyclin D1 plays an important role in the regulation of the G1 phase in the cell cycle. In mammary epithelial cells the expression of cyclin D1 is regulated through the oestrogen receptor and via ErbB2 signalling. Here we investigated the prognostic significance of cyclin D1 among 230 breast cancer patients randomised for tamoxifen, CMF chemotherapy and radiotherapy. The importance of combined cyclin D1 and ErbB2 overexpression was also analysed. Immunohistochemical analysis of the cyclin D1 expression resulted in 69 (29.8%) weakly positive, 107 (46.5%) moderately positive and 54 (23.7%) strongly positive cases. The prognostic importance of ErbB2 was significantly greater for patients whose tumours overexpressed cyclin D1 than for other patients (p = 0.026). In the former group, ErbB2 overexpression was strongly associated with increased risk of recurrence (RR = 4.7; 95% CI, 2.1–10.4) and breast cancer death (RR = 5.4; 95% CI, 2.3–12.6). This result is in accordance with experimental studies demonstrating a link between cyclin D1 and ErbB2 in oncogenesis. Among oestrogen receptor positive patients, those with moderate cyclin D1 expression significantly did benefit from tamoxifen treatment (RR = 0.42; 95% CI, 0.21–0.82) whereas those with weak or strong expression did not. Therefore cyclin D1 might be a predictive marker for tamoxifen resistance.     

The expressions and significance of α-, β-catenins and cyclin D1 in breast cancers

Objective  To study the relationship between expressions of α-, β-catenins and cyclin D1 and the occurrence, infiltration and metastasis of breast cancer. Methods  High sensitive S-P immunohistochemical method was used to detect the protein expressions of α-, β-catenins and cyclin D1 in the 60 cases of breast cancer tissues. Results  Abnormal immunoreactivities of α-and β-catenins were observed in 37 (61.7%) and 42 (70%) cases of breast cancer tissues, respectively. There were 28 cases (46.7%) who showed cyclin D1 overexpression. The abnormal expression rates of α-and β-catenins in infiltrating lobular carcinoma (ILC) were significantly higher than those in infiltrating ductal carcinoma (IDC) (P < 0.05), but they had no relations to the extent of differentiation and lymphatic metastasis of breast cancer (P > 0.05). The overexpression rate of cyclin D1 was correlated with tumor stage and lymphatic metastasis of breast cancer (P < 0.05), but not with histological type and the extent of differentiation (P > 0.05). Cyclin D1 overexpression was observed in 57.1% (24/42) of these cases that showed abnormal staining of β-catenin, but only observed in 22.2% (4/18) of these cases with normal membranous staining of β-catenin. There was a significantly positive correlation between the abnormal expression of β-catenin and overexpression of cyclin D1 (r _s = 0.321, P < 0.05). Conclusion  The abnormal expression of β-catenin may play an important role in the genesis of breast cancer by triggering cyclin D1 overexpression in breast cancer. The abnormal expressions of α-and β-catenins are not a key factor in malignant cell metastasis in breast cancer, but may also involve in the progress.     

Cyclin D1 overexpression is a critical event in gallbladder carcinogenesis and independently predicts decreased survival for patients with gallbladder carcinoma.

This study was designed to test the hypothesis that cyclin D1 overexpression is involved in the multistep process of gallbladder carcinogenesis and can be used to predict poor prognosis for patients with gallbladder carcinoma (GBC). Cyclin D1 expression was examined immunohistochemically in a series of specimens, including 8 normal epithelia, 8 benign adenomyoma lesions, 6 precancerous adenomas, and 37 carcinomas of the gallbladder. Four of the 6 (67%) adenomas and 15 of the 37 (41%) adenocarcinomas demonstrated cyclin D1 overexpression (>5% nuclear staining), whereas all normal epithelia and adenomyoma lesions were negative for cyclin D1. Kaplan-Meier curves showed that cyclin D1 overexpression was significantly related to decreased overall survival (P < 0.05) in patients with GBCs. The Cox proportional hazards model identified cyclin D1 overexpression as an independent prognostic marker for death (P = 0.024; risk ratio, 4.2; 95% confidence interval, 1.2-14.7). To test whether cyclin D1 overexpression is a critical event in gallbladder neoplasms, cyclin-dependent kinase inhibitor p27Kip1 was introduced to ascertain how cyclin D1 affects clinical outcomes. Subsequently, neoplasms were divided into three groups on the basis of the combination of cyclin D1 expression and p27Kip1 status, which had been determined previously. Group 1 showed no abnormality in either cyclin D1 or p27Kip1 expression. Group 2 showed aberrant expression of one of the two proteins, whereas group 3 showed concurrent abnormalities in both proteins. Results indicated that overall survival was greatest in group 1, followed by a significant decrease in group 2 and a more precipitous decrease in group 3. In conclusion, cyclin D1 overexpression is an early event in gallbladder carcinogenesis and independently predicts decreased survival for patients with GBC.     

Prognostic implication of cyclin E expression and its relationship with cyclin D1 and p27Kip1 expression on tissue microarrays of node negative breast cancer

BACKGROUND AND OBJECTIVES: Altered expression of cell-cycle regulators is prevalent in clinical breast cancer. This study was performed to analyze the impact of cyclin E expression to the outcome of breast cancer together with cyclin D1 and p27Kip1. METHODS: The correlation between cyclin D1/E and p27Kip1 expression was analyzed in tissue arrays of 175 node-negative breast cancers treated by the same chemotherapy composed of fluorouracil, cyclophosphamide, and methotrexate. Data from the immunohistochemical assays of three molecules were correlated and were analyzed with clinical outcome of the patients. RESULTS: Cyclin E expression was observed in 48 (27.4%) of 175 breast carcinomas. Cyclin E expression was significantly increased in young age patients and poorly differentiate tumors. Expression of cyclin E was significantly increased in cyclin D1 expressing tumors (P = 0.034). p27Kip1 expression was preserved above the 50% level in 87 tumors (49.7%) and was inversely correlated with cyclin E expression (P = 0.042). Ki67 labeling index was significantly increased in cyclin E-expressing tumors (P = 0.033) and was inversely related with p27Kip1 expression. In multivariate survival analysis, cyclin E expression was significant for the prediction of poor survival of the patients. CONCLUSIONS: Cyclin E expression was associated with poor prognosis and intimately correlated with the expression of cyclin D1 and p27Kip1. Integration of TMA technology allowed a high-throughput analysis for correlating molecular in situ findings with clinico-pathologic information.