Reduced retinoblastoma gene protein to Ki-67 ratio is an adverse prognostic indicator for ovarian adenocarcinoma patients

OBJECTIVE: Alterations in the retinoblastoma gene (RB-1) are common in human neoplasia. However, the clinical significance of the deregulated expression of RB-1 in ovarian cancer remains undefined. We therefore conducted a retrospective investigation to clarify the relationships of RB-1 gene protein (pRb) to the percentage of cycling cells, clinicopathologic variables, other G1 interacting proteins and prognosis of nonbenign epithelial ovarian tumors. METHODS: Paraffin-embedded tissue from 127 nonbenign epithelial ovarian tumors, including 44 of low malignant potential (LMP) and 83 primary ovarian adenocarcinomas, was stained immunohistochemically for pRb, p21(Cip1), p27(Kip1), p53, and Ki-67 antigen (a cell proliferation associated marker). Expression of these markers was correlated with clinicopathologic features and with overall survival of patients with adenocarcinomas. RESULTS: pRb levels were significantly lower in LMP tumors than in carcinomas (P = 0.027). In the latter group, pRb expression decreased with increasing grade (I-II vs III) (P = 0.010), advancing stage (I-II vs III) (P < 0.001), and bulk residual disease (P = 0.014). pRb was not related to Ki-67 expression (P > 0.10) or to overall survival (P > 0.10) but a low pRb to Ki-67 ratio emerged as an important indicator of poor survival in univariate analysis in the entire cohort (P = 0.0076) and in the platinum-treated patients (P = 0.0162) as well as in multivariate analysis, along with histologic type and FIGO stage. CONCLUSIONS: Diminished pRb levels are related to several clinicopathologic indicators of aggressiveness in ovarian adenocarcinomas. More importantly, pRb expression coupled with the percentage of Ki-67 positive cells is a better prognostic marker than pRb, Ki-67, or other G1 interacting proteins and supplements the information gained from traditional prognosticators.     

The combined evaluation of p27Kip1 and Ki-67 expression provides independent information on overall survival of ovarian carcinoma patients

OBJECTIVE: Considering the limited and controversial information on the significance of the cyclin-dependent kinase inhibitor p27Kip1 in ovarian cancer, we conducted a retrospective investigation to clarify the relationships of this protein to proliferation rate, clinicopathologic variables, and prognosis of epithelial ovarian tumors. METHODS: Paraffin-embedded tissue from 43 ovarian tumors of low malignant potential (LMP) and 80 primary ovarian adenocarcinomas was stained immunohistochemically for p27Kip1, Ki-67 antigen (a marker of cell proliferation), and p53 protein. Expression of these markers was correlated with clinicopathologic features and with overall survival of patients with adenocarcinomas. RESULTS: p27Kip1 levels were significantly higher in LMP tumors as well as in low-grade, early-stage, slowly proliferating adenocarcinomas and those associated with minimal residual disease (P < 0.001). Decreased p27Kip1 expression was related to poor overall survival on its own (P = 0.0304) and, when combined, to increased proliferation rate (P = 0.0232). More importantly, in multivariate analysis, p27Kip1/Ki-67 status was independently related to survival (P = 0.040) along with histologic type and FIGO stage. CONCLUSION: Decreased p27Kip1 expression is related to several clinicopathologic indicators of aggressiveness in ovarian adenocarcinomas and is a major player in cell cycle control in these neoplasms. On the contrary, deregulation of the protein does not seem to participate in the pathogenesis of LMP tumors. Furthermore, combined p27Kip1/Ki-67 expression is a better prognostic marker than expression of p27Kip1 or Ki-67 alone and supplements the prognostic information gained from traditional prognosticators.     

Expression of cell cycle proteins in ovarian carcinoma cells in serous effusions-biological and prognostic implications

OBJECTIVE: The aim of this study was to investigate the expression of cell cycle proteins in ovarian carcinoma cells in serous effusions and respective solid tumors. METHODS: Fifty-five malignant effusions and 38 tumors (20 primary, 18 metastatic) were immunohistochemically stained for cyclin A, p27(kip1), and Ki-67. Staining extent (0-100% cells) and intensity (0-3 scale) were scored. Cyclin A and p27(kip1) expression was additionally studied in 29 malignant effusions using immunoblotting. Immunohistochemistry results in effusions were evaluated for possible association with clinicopathologic parameters. RESULTS: Nuclear immunoreactivity for all markers was detected on carcinoma cells in the majority of effusions using immunohistochemistry. Similarly, immunoblotting showed the presence of cyclin A and p27(kip1) in 29/29 and 25/29 specimens, respectively. Intense (3) immunoreactivity for Ki-67 was detected more often in peritoneal effusions, compared with those of pleural location (P = 0.036). Staining in primary and metastatic lesions was generally comparable to that of tumor cells in effusions. Staining for p27(kip1) was more diffuse in effusion specimens obtained prior to the institution of chemotherapy (P = 0.042). In an analysis of all effusions, an association was observed between the number of cells that were immunoreactive for Ki-67, cyclin A, and p27(kip1) (cyclin A-Ki-67: P = 0.008; p27(kip1)-Ki-67: P = 0.019; cyclin A-p27(kip1): P = 0.032). In survival analysis, the presence of more diffuse (P = 0.042) and intense (P = 0.019) staining for cyclin A correlated with prolonged overall survival. CONCLUSIONS: The expression of the studied cell cycle markers does not differ markedly between ovarian carcinoma cells in the pleural and peritoneal cavity, supporting our previous studies of several metastasis-associated molecules. The presence of cyclin-A-positive cell populations is associated with a more favorable disease outcome, possibly due to the targeting of proliferating cells by chemotherapeutic agents. However, the decline in the fraction of p27(kip1)-positive cells in posttreatment specimens may point to additional mechanisms involved in this selection.     

卵巢上皮性肿瘤中细胞周期素D1蛋白与p16蛋白的表达及其临床意义

目的　探讨细胞周期素D1蛋白 (cyclinD1)与 p16蛋白在卵巢上皮性肿瘤中的表达及临床意义。 方法　 1998年 1月至 2 0 0 0年 1月采用免疫组化SP法 ,检测恶性、交界性、良性卵巢上皮性肿瘤、正常卵巢组织中的cyclinD1蛋白和p16蛋白的表达。结果　cyclinD1蛋白、p16蛋白表达的阳性率分别为恶性 5 0 %和 4 0 %、交界性30 %和 5 0 %、良性卵巢上皮性肿瘤 0和 80 %、正常卵巢组织中 0和 90 %。恶性卵巢上皮性肿瘤与良性卵巢上皮性肿瘤及正常卵巢组织之间比较 ,cyclinD1蛋白的表达差异有显著性意义 (P <0 0 1) ,p16蛋白的表达差异有显著性意义 (P <0 0 5 )。在恶性程度较高 ,组织分化差 ,晚期的恶性卵巢上皮性肿瘤中cyclinD1蛋白表达率高 ,p16蛋白的表达率低。相关性分析显示 ,cyclinD1蛋白与 p16蛋白的表达呈负相关。 结论　cyclinD1蛋白的过度表达与 p16蛋白表达的缺失在恶性卵巢上皮性肿瘤的发生、发展中起一定作用 ,二者可能存在相互抑制机制。     

Cyclin D1 overexpression and p53 mutation status in epithelial ovarian cancer

OBJECTIVE: To examine the cyclin D1 mRNA expression level in ovarian tumor samples as compared with normal ovaries and to determine the relationship between cyclin D1 overexpression and p53 mutation status in ovarian tumors. METHODS: mRNA was isolated and cDNA was prepared from 27 epithelial ovarian tumors (3 tumors of low malignant potential (LMP) and 24 cancers) and 6 normal ovaries. The cyclin D1 sequences were amplified by using a thermal cycler in parallel with the beta-tubulin gene as an internal control. The cyclin D1 mRNA expression level relative to beta-tubulin was determined by 32P phosphoimager analysis. To confirm the overexpression of the cyclin D1 protein in ovarian tumor cells, immunostaining was performed. The p53 gene mutation status was examined by direct cDNA sequencing. RESULTS: mRNA levels of cyclin D1 were significantly higher in 21 (78%) of the 27 ovarian tumors than in normal ovaries. Cyclin D1 overexpression was detected in ovarian LMP tumors as well as in ovarian cancer cases. Positive immunostaining of cyclin D1 protein was observed in 10 of 18 (56%) ovarian tumors examined. p53 mutations were found in 11 (61%) of 18 ovarian tumors. Of 11 ovarian tumor cases with p53 mutations, 5 showed overexpression of cyclin D1. All 7 ovarian tumor cases without p53 mutations showed significant cyclin D1 mRNA overexpression. CONCLUSION: Cyclin D1 overexpression seems to be an early genetic event in ovarian tumor development. Although p53 may be one of the proteins whose function regulates the expression of G1 cyclins, ovarian tumors with no p53 mutation consistently showed cyclin D1 overexpression. Cyclin D1 overexpression may play an important role in the tumorigenesis of epithelial ovarian tumors.     

Expression of the cell-cycle regulatory proteins (cyclins D1 and E) in endometrial carcinomas: correlations with hormone receptor status, proliferating indices, tumor suppressor gene products (p53, pRb), and clinicopathological parameters

PURPOSE OF INVESTIGATION: This study aimed to investigate the immunohistochemical expression of cyclins D1 and E in normal, hyperplastic and neoplastic endometrium, and their correlation with proliferative activity and clinicopathological features. METHODS: We carried out immunohistochemical techniques on archived material of formalin-fixed paraffin-embedded tissues using the antibodies against the cyclins D1 and E, PR-ER, p53, Ki67 (MIB1) and pRb with the streptavidin-biotin-peroxidase method in a total of 20 cases of normal endometrium, 32 cases of hyperplastic endometrium and 66 cases of endometrial carcinomas. RESULTS: Cyclin D1 and E immunoreactivity was observed in the nuclei of tumour cells in 18.2% and 39.1%, respectively, of the cases of endometrial carcinomas. Cyclin D1 labelling index was not significantly correlated with any of the clinicopathologic parameters examined. However, there was a significant correlation between the cyclin E labelling index and histological grade of carcinoma (p = 0.00096), which increased significantly with histological grades of malignancy. We also detected a significant correlation between cyclin E and PCNA (p < 0.0001) as well as with the tumor suppressor genes p53 and pRb (p = 0.052 and 0.0002, respectively) in endometrioid endometrial carcinoma. CONCLUSION: Our results indicate that cyclin E overexpression may be involved in the development and/or proliferation and differentiation of human endometrioid endometrial carcinoma. Immunoexpression of cyclin D1 does not appear to be associated with cell-cycle progression in the benign or malignant endometrium.     

上皮性卵巢肿瘤cyclin B1和p27的表达及其意义

目的:探讨cyclin B1和p27在上皮性卵巢肿瘤发生、发展及预后中的作用。方法:应用免疫组化S-P法检测正常卵巢(20例)、良性上皮性卵巢肿瘤(20)及恶性上皮性卵巢肿瘤(20例)中cyclin B1和p27的表达,分析其表达水平与肿瘤恶性程度、临床分期及淋巴转移间的关系。结果:cyclin B1在恶性上皮性卵巢肿瘤中的表达水平高于正常卵巢和良性肿瘤,差异有显著性(P<0.05);p27在正常卵巢、良性肿瘤和恶性肿瘤中的阳性表达呈显著性递减趋势(P<0.05);cyclin B1表达与肿瘤的临床分期及淋巴转移显著相关(P<0.05)。结论:cyclin B1高表达和p27低表达,可能与卵巢肿瘤的发生、发展密切相关。     

Overexpression of cyclin D1 and c-Myc gene products in human primary epithelial ovarian cancer

Cyclin D1 and c-Myc are key participants in the cell-cycle pathway, in which aberrancies have been associated with malignant transformation. To date, data on the relationship of expression of these proteins and histologic subtype of epithelial ovarian cancer are still scarce and discordant. Immunohistochemical analysis was performed on 12 normal ovaries and 47 cases of serous, mucinous, endometrioid, and clear cell ovarian carcinomas. No abnormal expression of cyclin D1 or c-Myc was demonstrated in any of the 12 normal ovarian specimens. However, compared to normal ovarian tissues, overexpression of cyclin D1 and c-Myc was observed in 42.6% (20/47) and 65.9% (31/47) of tumors examined, respectively. There was no significant difference of overexpression of cyclin D1 or c-Myc gene products between these four histologic subtypes of ovarian adenocarcinomas. This study shows that cyclin D1 and c-Myc are frequently overexpressed in epithelial ovarian carcinomas, but they are not correlated with a particular histologic subtype. Although our preliminary results need to be validated in a larger number of tumors, the abnormal expression of cyclin D1 and c-Myc in epithelial ovarian cancer reaffirms the notion that they are crucial components in the pathway of tumorigenesis and deserve further study.     

Prognostic significance of cell cycle proteins and genomic instability in borderline, early and advanced stage ovarian carcinomas

Abstract. Blegen H, Einhorn N, Sjövall K, Roschke A, Ghadimi M, McShane LM, Nilsson B, Shah K, Ried T, Auer G. Prognostic significance of cell cycle proteins and genomic instability in borderline, early and advanced stage ovarian carcinomas.
Disturbed cell cycle-regulating checkpoints and impairment of genomic stability are key events during the genesis and progression of malignant tumors. We analyzed 80 epithelial ovarian tumors of benign ( n = 10) and borderline type ( n = 18) in addition to carcinomas of early ( n = 26) and advanced ( n = 26) stages for the expression of Ki67, cyclin A and cyclin E, p21^WAF–1, p27^KIP–1 and p53 and correlated the results with the clinical course. Genomic instability was assessed by DNA ploidy measurements and, in 35 cases, by comparative genomic hybridization. Overexpression of cyclin A and cyclin E was observed in the majority of invasive carcinomas, only rarely in borderline tumors and in none of the benign tumors. Similarly, high expression of p53 together with undetectable p21 or loss of chromosome arm 17p were frequent events only in adenocarcinomas. Both borderline tumors and adenocarcinomas revealed a high number of chromosomal gains and losses. However, regional chromosomal amplifications were found to occur 13 times more frequently in the adenocarcinomas than in the borderline tumors. The expression pattern of low p27 together with high Ki67 was found to be an independent predictor of poor outcome in invasive carcinomas. The results provide a link between disturbed cell cycle regulatory proteins, chromosomal aberrations and survival in ovarian carcinomas.     

Correlation of cyclin D1 and cyclin D3 overexpression with the loss of PTEN expression in endometrial carcinoma

Cyclins D1 and D3 play key roles in cell cycle progression. The downregulation of cyclin D3 was associated with phosphatase and tensin homolog deleted on chromosome ten-(PTEN)-induced cell cycle arrest. We attempted to determine whether cyclin D1 and D3 overexpression is correlated with PTEN inactivation in endometrioid endometrial cancer (EEC). The expression of PTEN, cyclin D1, and cyclin D3 were determined by immunohistochemical analysis in 105 EEC specimens. Forty-three percent of the EEC demonstrated loss of PTEN expression. Cyclin D3 was overexpressed in only 18% of the EEC specimens and was not associated with tumor grade. Cyclin D1 was overexpressed in 64% of the specimens and was more common in moderate or high-grade tumors (P = 0.002 and P = 0.02, respectively). The overexpression of cyclin D3 was not correlated with loss of PTEN in the EEC. The overexpression of cyclin D1 was much higher in grade 1 tumors with negative PTEN than tumors with positive PTEN expression (67% vs 26%). The overexpression of cyclin D3 was neither frequent nor correlated with the loss of PTEN expression. The overexpression of cyclin D1 was higher in the low-grade tumors with negative PTEN expression than tumors with positive PTEN expression. Overexpression of cyclin D1 is frequent in moderate or high-grade EECs and likely results from multiple mechanisms.     

卵巢癌中p27kip1和Cyclin D1的表达与预后因素的相关性研究

目的　探讨 p2 7kip1、CyclinD1在卵巢癌发生、发展方面的意义。 方法　应用免疫组化染色及半定量分析的方法 ,检测 5 0例卵巢癌、19例卵巢良性上皮肿瘤、13例正常卵巢组织中的p2 7kip1、CyclinD1表达 ,及它们与上皮组织的良恶性、病理组织分级、临床分期的相关性。结果　正常卵巢组和卵巢良性肿瘤组间 ,p2 7、CyclinD1表达无明显差异 ;p2 7在正常卵巢组织和卵巢良性上皮肿瘤中高表达 ,在卵巢癌中表达降低 (P <0 0 5 ) ,且随着肿瘤分级、分期增高 (恶性程度增高 ) ,阳性表达率逐渐下降 ;而CyclinD1的表达则相反 ;两者在肿瘤中的表达呈负相关。结论　p2 7kip1表达下降、CyclinD1过表达可能在卵巢癌的发生发展中起重要作用 ,检测 p2 7kip1、CyclinD1在卵巢癌中的表达可预测该肿瘤生物学行为特征 ,可以作为预后指标     

Cyclin D1 and retinoblastoma protein in vulvar cancer and adjacent lesions

Abstract. Rolfe KJ, Crow JC, Benjamin E, Reid WMN, Maclean AB, Perrett CW. Cyclin D1 and retinoblastoma protein in vulvar cancer and adjacent lesions.
Abnormalities in the cell cycle are associated with tumorigenesis but have not yet been identified in squamous cell carcinoma (SCC) of the vulva or in adjacent vulvar lesions. The purpose of this study was to identify cell cycle protein expression (cyclin D1 and retinoblastoma protein [pRb]) in vulvar SCC and in adjacent potentially premalignant lesions: lichen sclerosis (LS), squamous cell hyperplasia (SH), and vulvar intraepithelial neoplasia (VIN). Using immunohistochemical techniques, 57 SCCs were analyzed with 19 adjacent areas showing LS, 13 showing SH, 11 VIN, and six normal epithelium. Fifty-one percent of SCCs showed abnormal cyclin D1 expression and 37% showed abnormal pRb. Abnormal cyclin D1 expression in the adjacent areas was as follows: 53% in LS, 31% in SH, 18% in VIN, and 0% in normal. Abnormal pRb expression was as follows: 42% in LS, 62% in SH, 46% in VIN, and 33% in normal. Only 10 lesions showed abnormal expression of both proteins. Abnormal expression of cyclin D1 in SCC was statistically significant compared with adjacent normal epithelium. In SCC lesions, abnormal cyclin D1 expression was associated with greater depth of invasion. Abnormal pRb in SCC was associated with poor tumor grade. Cyclin D1 and pRb are separately involved in the progression of vulvar cancer, and changes in the expression of these proteins may represent an early stage of malignant transformation in vulvar disease.     

Expression of tumor suppressor gene product p14ARF in endometrioid adenocarcinoma of the uterine corpus.

p14 activates p53 by inhibiting MDM2 expression and arrests the cell cycle in G1 and G2/M. Abnormal p14 expression has been reported in various human cancers. This study investigated p14 expression in endometrioid adenocarcinoma of the uterine corpus in an attempt to clarify its correlation with other cell cycle-regulators and clinicopathologic parameters. The specimen studied consisted of 124 endometrioid adenocarcinomas, 20 normal endometria, and 20 endometrial hyperplasias. Immunohistochemical staining of formalin-fixed and paraffin-embedded tissues was performed using a Catalyzed Signal Amplification System. Cells with >5% positive staining were classified as positive for p14. A staining score of 1 was adopted when the percentage of positive nuclei was <5%, a score of 2 when it was 5 to 50%, and a score of 3 when it was >50%. In normal endometrium, the frequency of positive staining in the proliferative phase and secretory phase was 50% (4/8) and 58.3% (7/12), with staining scores of 1.8+/-0.9 and 1.6+/-0.5, respectively. The frequency of staining in simple hyperplasia (SH), complex hyperplasia (CH), and complex atypical hyperplasia (CAH) was 88.9% (8/9), 25% (1/4), and 42.9% (3/7), respectively; the staining scores were 1.9+/-0.3, 1.3+/-0.5, and 1.4+/-0.5, respectively. Among endometrioid adenocarcinomas, the frequency of staining of well-differentiated (G1), moderately differentiated (G2), and poorly differentiated (G3) adenocarcinomas was 69% (49/71), 64% (16/25), and 42.9% (12/28) respectively, with staining scores of 2.1+/-0.8, 2+/-0.9, and 1.8+/-1, respectively. Thus expression levels of p14 were higher in G1 tumors than in normal endometria or endometrial hyperplasias, and the frequency of its staining in endometrioid carcinomas was inversely correlated with histologic grade. The staining score for endometrioid adenocarcinomas also was inversely correlated with the labeling index (LI) of Ki-67, but not with that of cyclin A, cyclin D1, cyclin E, cdk2, p27, p53, or other clinicopathologic parameters. In conclusion, p14 expression correlated with histologic grade and Ki-67, but not other prognostic factors in endometrioid adenocarcinoma. Long-term follow-up studies are needed to analyze the significance of p14 expression in these tumors.     

The concurrent expression of p27(kip1) and cyclin D1 in epithelial ovarian tumors.

Mammalian cell-cycle progression is regulated by the combined action of cyclins/cyclin-dependent kinases (cdks) and cdk inhibitors. Abnormal expression as well as interaction of these proteins may result in malignant transformation of cells. To further address alterations and roles of these cell-cycle proteins in the development of epithelial ovarian carcinomas, we analyzed the expression of the p27(kip1), cyclin D1, cyclin E, and cdk2. A panel of 79 epithelial ovarian tumors was selected. Immunohistochemical staining of serial paraffin sections was performed using antibodies to p27(kip1), cyclin D1, cyclin E, and cdk2. The results showed that p27(kip1) and cyclin D1 were concurrently expressed in epithelial ovarian tumors, and the expression was down-regulated in ovarian carcinomas. There was an inverse relationship between the expression level of p27(kip1) and cyclin D1 and the histological tumor grades. On the other hand, the expression of cyclin E and cdk2 was enhanced in ovarian carcinomas. The results suggest that low expression of p27(kip1) and cyclin D1 as well as high expression of cyclin E and cdk2 promotes the development of ovarian tumors. p27(kip1) and cyclin D1 expression are negatively correlated with the malignant degree of epithelial ovarian tumors. Thus, the ovarian tumors with high p27(kip1) and cyclin D1 expression may generally have a somewhat better prognosis, while those with low p27(kip1) and cyclin D1 expression may have a worse prognosis.     

细胞周期p16-cyclin D1-pRb调节通路与人卵巢浆液性囊腺癌的相关性研究

目的 :探讨细胞周期 p16 - p Rb- cyclin D1调节通路及各因子在浆液性卵巢肿瘤发生和发展中的作用。方法 :应用免疫组化 L s AB法检测一组浆液性卵巢肿瘤中 p16、p Rb和 cyclin D1蛋白表达情况。结果 :卵巢浆液性囊腺癌原发灶和淋巴结转移灶中 p16表达阳性率明显低于正常卵巢、良性肿瘤和交界性肿瘤 ;p16 - p Rb- cyclin D1调节通路异常率却呈相反趋势变化 ,且通路异常与浆液性囊腺癌 FIGO分期、组织学分级及预后无明显相关性。 p16表达阳性患者术后生存率高于阴性患者 (P=0 .0 0 0 6 )。p Rb和 cyclin D1表达情况与卵巢浆液性囊腺癌组织学分级、FIGO分期无明显关系。卵巢浆液性肿瘤组织中 p16和 p Rb蛋白表达呈负相关。结论 :p16蛋白在卵巢浆液性肿瘤的发生、发展中可能起着较为重要的作用。 p16 - p Rb- cyclin D1调节通路异常在浆液性卵巢肿瘤虽很常见 ,但其具体作用尚不清楚     

Cyclin E mRNA overexpression in epithelial ovarian cancers: inverse correlation with p53 protein accumulation

OBJECTIVE:We investigated the relationship between cyclin E mRNA overexpression and p53 protein accumulation in epithelial ovarian cancers. METHODS: mRNA was isolated and cDNA was prepared from 36 epithelial ovarian tumors (three adenomas, three low malignant potential tumors, and 30 carcinomas), and six normal ovaries. The cyclin E mRNA expression levels relative to an internal control, beta-tubulin, were determined by semiquantitative polymerase chain reaction (PCR). Cyclin E and p53 protein expression in ovarian cancer tissues were examined by immunohistochemistry using the same series of samples. Fisher exact test of significance and an unpaired t test were used for statistical analysis. RESULTS: Considerable levels of cyclin E mRNA were detected in all normal ovaries and ovarian tumor samples examined by semiquantitative PCR amplification. mRNA levels of cyclin E were significantly higher in nine of 30 (30%) ovarian cancers compared with those in normal ovaries. The immunohistochemical expression of cyclin E protein was confirmed in the nuclei of tumor cells in 13 of 30 (43%) ovarian cancers. p53 protein accumulation was detected in 12 of 30 (40%) ovarian cancers examined. There was a significant inverse correlation between cyclin E mRNA overexpression and p53 protein accumulation (P <.01, Fisher exact test). CONCLUSIONS: Cyclin E mRNA overexpression frequently occurs in ovarian cancers without p53 protein accumulation. Cyclin E might have an important effect on the development of a limited number of ovarian cancers.     

Expression of the cell-cycle regulatory proteins (pRb,cyclin D1, p16INK4A and cdk4) in human endometrial cancer: correlation with clinicopathological features

Introduction. Derailments of the control mechanisms in the G1/S phase of the cell cycle play a fundamental role in the initiation and progression of cancer. However, only a few reports have addressed the issue of simultaneously occurring abnormalities of Rb-pathway components in malignant endometrial tumors. Methods. Currently, we assessed the expression of cell-cycle regulatory proteins (pRb, cyclin D1, p16^INK4A and cdk4) in 48 sporadic endometrial cancers, and investigated these tumors for a possible relationship between aberrant protein staining and clinicopathological variables of cancer and RB-LOH. Results. There was abnormal pRb, cyclin D1, p16^INK4A and cdk4 immunoreactivity in 2%, 50%, 6% and 25% of cases, respectively. Altogether, 33 of 48 (69%) endometrial malignant tumors showed abnormal expression of at least one Rb-pathway protein immunohistochemically. However, there was significant correlation neither between the cell-cycle regulators nor between the frequency of pRb, p16^INK4A and cyclin D1 abnormalities and clinicopathological variables of cancer, but a significant correlation did exist between cdk4 staining and the clinical stage of disease (P<0.05, Fisher's exact test). Moreover, an inverse relationship was also demonstrated between cdk4 expression and patient age (r=-0.367; P=0.01). However, none of the cell-cycle regulatory proteins, except for pRb, was related to loss of heterozygosity at locus 13q14. Conclusion. As a conclusion, derailments of the Rb-pathway components, cyclin D1 and cdk4 in particular, seems to participate in the endometrial cancer development in humans. Overexpression of cdk4 was related to the progression of neoplastic disease and corresponds with age of onset, suggesting a major role of altered cdk4 immunoreactivity in the progression of endometrial cancer.     

Cyclins and proliferation markers in early squamous cervical carcinoma

OBJECTIVES: To examine the prognostic significance of the protein expression of cyclin E, cyclin A and cyclin D3, and of the proliferation markers Ki-67 and BM28 in early squamous cervical carcinoma (SCC). METHODS: Tissue blocks from 221 patients who underwent radical hysterectomy and bilateral lymphadenectomy at our institution for stage IB SCC between 1987 and 1993 were available for this study. Immunohistochemistry using monoclonal antibodies against cyclin E, cyclin A, cyclin D3, Ki-67 and BM28 was used to examine protein expression. Ten patients who underwent hysterectomy for uterine prolapse served as controls. RESULTS: Cyclin E, cyclin A, Ki-67 and BM28 expression was increased in SCC and high expression was observed in 81.5% (180/221), 35% (78/221), 25.5% (56/221) and 92% (204/221) of tumors, respectively. Cyclin D3 was decreased in SCC and low expression was found in 50.5% (111/220) of tumors. In univariate analysis, all classical clinicopathological parameters but none of the investigated proteins were associated with prognosis. In multivariate analysis, only deep stromal invasion was independently related to survival. CONCLUSION: Cyclin E, cyclin A and cyclin D3 and the proliferation markers Ki-67 and BM28 are not independently associated with prognosis in stage IB SCC.     

The clinical importance of Ki-67, p16, p14, and p57 expression in patients with advanced ovarian carcinoma.

The present study addressed the impact of p14, p16, p57, and Ki-67 in a large cohort of uniformly treated patients with stage III ovarian cancer in relation to other clinicopathologic variables and prognosis. We immunohistochemically studied 171 primary tumors from previously untreated patients with advanced ovarian carcinomas for expression of Ki-67, p16, p14, and p57. High protein levels of Ki-67 (>10% positive nuclei) were found in 144 cases (84%), p16 (>50% positive nuclei) in 53 cases (31%), p57 (>10% positive nuclei) in 41 cases (24%), and p14 (any positive nuclei) in 19 cases (11%). A correlation between high Ki-67 expression and presence of residual disease after primary surgery (P = 0.019), ascites (P = 0.006), higher International Federation of Gynecology and Obstetrics substage (P < 0.001), poor differentiation (P < 0.001), and higher Silverberg histopathologic grade (P < 0.0001) was seen. High expression of p16 correlated to poor differentiation (P = 0.033) and higher Silverberg histopathologic grade (P = 0.018). In univariate analysis, high expression of Ki-67 (P = 0.0001) and p16 (P = 0.005) was associated with poor survival. However, in multivariate analysis, only high expression of Ki-67 was significantly associated with shorter survival (P = 0.025). No correlations were seen between expression of p14 and p57 and clinicopathologic parameters. None of the factors studied was able to predict response to chemotherapy. Our results showed that Ki-67 represents an independent prognostic predictor in stage III ovarian cancer. We did not find p16, p14, and p57 to be useful as prognostic markers.