Expression levels of eIF4E, VEGF, and cyclin D1, and correlation of eIF4E with VEGF and cyclin D1 in multi-tumor tissue microarray

The mRNA cap-binding protein, eukaryotic initiation factor 4E (eIF4E), is a rate-limiting factor of cap-dependent translation initiation. When elevated, eIF4E greatly facilitates translation of a selected spectrum of mRNAs coding for proteins critical to angiogenesis and growth such as vascular endothelial growth factor (VEGF) and cyclin D1. Expression levels of eIF4E, VEGF, and cyclin D1 were examined in multi-tumor tissue microarray by immunohistochemistry and analyzed quantitatively. eIF4E, VEGF and cyclin D1 protein were elevated in tumors of the breast (62, 78, or 40%), colon (72, 77, or 12%), glioblastoma multiforme (48, 68, or 52%), lymphoma (66, 74, or 38%), melanoma (59, 73, or 58%), NSCLC (81, 82, or 29%), ovary (50, 39, or 13%), and prostate (78, 97, or 21%), respectively. eIF4E levels were strongly correlated with VEGF and cyclin D1 in melanoma (Spearman's r=0.97 and 0.77; all P<0.0001); moderately in tumors of the breast (r=0.55 and 0.41; all P<0.0005), colon (0.63 and 0.56; all P<0.0001), lung (0.53 and 0.53; all P<0.005), lymphoma (0.50 and 0.61; all P<0.0005), prostate (0.46 and 0.54; all P<0.005), or ovary (0.56 and 0.46; all P<0.005); and weakly in tumors of glioblastoma multiforme (r=0.20 and 0.31; all P>0.15). The significant association of eIF4E with VEGF and cyclin D1 in multiple tumors supports a role for eIF4E in translational regulation of proteins related to angiogenesis and growth.     

Cyclin D1, p16 and retinoblastoma gene product expression as a predictor for prognosis in non-small cell lung cancer at stages I and II.

The association of the immunohistochemical expressions of cyclin D1, p16 and the retinoblastoma gene product (pRB) with the prognoses of 106 patients with non-small cell lung cancer (NSCLC) at stages I and II after a complete resection was investigated. We used antibodies recognizing nuclear and cytoplasmic cyclin D1, p16 and pRB. In 106 tumors, the positive rates of cyclin D1, p16 and pRB were 46, 54 and 48%, respectively. Cyclin D1-positive (cyclin D1(+)) patients had significantly poorer survival prognoses than cyclin D1-negative (cyclin D1(-)) patients (log-rank test, P=0.0002; Wilcoxon test, P=0.0005), whereas p16-positive (p16(+)) patients had significantly better prognoses than p16-negative (p16(-)) patients (log-rank test, P=0.0063; Wilcoxon test, P=0.0044). The survival period was over 65% for patients with cyclin D1(-)/p16(+) (n=34) at 120 months after surgery, whereas patients with cyclin D1(+)/p16(-) patients (n=22) had a 50% survival period at 49 months. The cumulative survival rate of cyclin D1(+)/p16(-) patients was significantly lower than that of cyclin D1(-)/p16(+) patients (log-rank test, P=0.0004; Wilcoxon test, P=0.0002). The pRB did not influence significantly the survival rate. Our results indicate that cyclin D1 and p16, especially a combination of cyclin D1 and p16, are very useful to predict the prognosis of patient with NSCLC after curative resection independent of pathological stages I and II.     

胃癌eIF4E和cyclin D1表达及其临床病理意义

 目的研究真核细胞起始因子4E(eIF4E)及cyclin D1在胃癌中的表达及临床意义,探讨eIF4E与cyclin D1之间的相关性。方法应用免疫组化的方法检测91例胃癌及30例正常胃组织中eIF4E及cy-clinD1的表达。结果eIF4E、cyclin D1在正常胃组织中均为阴性表达,在胃癌组织中的阳性表达率分别为95.6%(87/91)和84.6%(77/91)。eIF4E及cyclin D1表达与胃癌浸润深度、淋巴结转移以及临床分期有关(P<0.05),但与肿瘤组织学分化程度、年龄、性别无关。胃癌组织中eIF4E与cyclin D1表达密切相关(P<0.05)。结论检测eIF4E和cyclin D1表达水平,对于判断胃癌的恶性程度有重要意义。     

Immunoreactivity for p27(KIP1) and cyclin E is an independent predictor of survival in primary gastric non-Hodgkin's lymphoma.

Our aim was to assess the prognostic implications of the expression of p27(KIP1) and cyclin E in gastric lymphoma. We investigated the prognostic value of the immunoreactivity of these molecules in 92 cases of primary gastric lymphoma: 34 LGMLs, 24 DLCLMLs and 34 DLCLs. p27 was positive in 88% of LGMLs, 71% of DLCLMLs and 32% of DLCLs (p = 0.004); cyclin E was positive in 9%, 33% and 59% of cases, respectively (p < 0.00001). p27/cyclin E immunoreactivity significantly correlated with histologic category, stage and LDH serum level. p27 immunoreactivity was significantly associated with better survival, whereas cyclin E reactivity was significantly related to worse outcome. Five-year CSS was 94% for patients with p27(+)/cyclin E(-) phenotype (n = 42), 79% for p27(+)/cyclin E(+) (n = 14) or p27(-)/cyclin E(-) (n = 16) phenotype and 60% for p27(-)/cyclin E(+) phenotype (n = 16) (p = 0.02). The prognostic role of p27/cyclin E expression was confirmed when analyzed separately within LGMLs and large-cell lymphomas. Immunoreactivity for p27 and cyclin E is an independent predictor of survival in PGLs that may be an adjunctive tool in identifying high-risk patients. It correlates with histologic category, stage and LDH serum level. p27(-)/cyclin E(+) phenotype is associated with worse survival, probably due to a synergistic effect of both cell-cycle defects. The predictive role of these molecules within each histologic group of PGLs deserves to be confirmed in larger series.     

Expression of eukaryotic initiation factor 4E predicts clinical outcome in patients with mantle cell lymphoma treated with hyper‐CVAD and rituximab,alternating with rituximab,high‐dose methotrexate,and cytarabine

BACKGROUND:

Oncogenic AKT/mammalian target of rapamycin (mTOR) signaling has recently been shown to contribute to tumor survival and proliferation in mantle cell lymphoma (MCL) through its downstream effector eukaryotic initiation factor 4E (eIF4E), which may control cyclin D1 protein levels. However, the clinical significance of eIF4E expression in MCL is unknown.

METHODS:

The authors investigated the prognostic significance of eIF4E expression in 70 MCL patients uniformly treated with hyper‐CVAD and rituximab, alternating with the rituximab, high‐dose methotrexate, and cytarabine regimen (R‐hyper‐CVAD). eIF4E expression was assessed using tissue biopsy specimens obtained before treatment, immunohistochemical methods, and a highly specific monoclonal antibody. Failure‐free (FFS) and overall (OS) survival were used as endpoints in univariate and multivariate survival analysis.

RESULTS:

High eIF4E expression was found in 28 (40%) MCL tumors. After a median follow‐up of 51 months for survivors, the 5‐year FFS was 20.6% for patients with high eIF4E expression, compared with 63.5% for patients with low or no eIF4E expression (P = .01, log‐rank). Similarly, the 5‐year OS was 40.1% for patients with high eIF4E expression, compared with 73.8% for patients with low or no eIF4E expression (P = .018, log‐rank). In multivariate analysis, eIF4E expression was associated with poorer FFS and OS, along with age >60 years and high β₂–microglobulin in the final prognostic model.

CONCLUSIONS:

In summary, eIF4E, which seems to recapitulate most of the biologic effects of mTOR signaling in MCL, is an independent predictor of clinical outcome in MCL patients uniformly treated with the R‐hyper‐CVAD regimen. Cancer 2009. © 2009 American Cancer Society.     

Inhibition of Myc-dependent apoptosis by eukaryotic translation initiation factor 4E requires cyclin D1

Ectopically expressed eukaryotic translation initiation factor 4E (eIF4E) stimulates cell proliferation, suppresses apoptosis in growth factor restricted cells, and induces malignant transformation in primary rodent fibroblasts when coexpressed with protooncogene myc. We report here that eIF4E rescued rat embryo fibroblasts ectopically expressing c-Myc (REF/Myc) from genotoxic and non-genotoxic cytostatic drugs and identify cyclin D1 as a downstream effector in the antiapoptotic mechanism. In clones of REF/Myc ectopically expressing eIF4E, resistance to apoptosis paralleled steady state levels of cyclin D1. Stable expression of cyclin D1 in REF/Myc inhibited apoptosis in response to a broad range of cell cycle specific cytostatic agents. Partial loss-of-cyclin D1 function in REF/Myc ectopically expressing eIF4E (REF/Myc/4E) significantly increased chemosensitivity; either soluble antisense cyclin D1 oligomers or transfection with a dominant negative cyclin D1 mutant that prevents translocation of cyclin D-dependent kinases to the nucleus, significantly blunted the antiapoptotic effect of eIF4E. These data directly link eIF4E rescue from cytostatic drugs to cyclin D1. Since overexpression of eIF4E and cyclin D1 is observed in many aggressive forms of chemoresistant cancers, these findings provide insight into possible mechanisms responsible for this biological behavior.     

Cyclin D1 expression in transitional cell carcinoma of the bladder: correlation with p53, waf1, pRb and Ki67

Normal cell proliferation is closely regulated by proteins called cyclins. One of these, cyclin D1, in combination with its corresponding cyclin-dependent kinase (cdk), is essential for G(1)/S phase transition. Cyclin/cdk complexes are generally inhibited by cyclin-dependent kinase inhibitors(ckis), some of which are induced by wild-type p53. The aims of this study were: to investigate levels of cyclin D1 expression in transitional cell carcinoma (TCC) of the bladder; to correlate these results with data concerning the expression of p53, waf1, pRb and Ki67; and to determine whether cyclin D1 expression could predict clinical outcome. Paraffin-sections from 150 newly diagnosed bladder tumours (Ta/T1 = 97; T2-T4 = 53) were stained for cyclin D1 using immunohistochemistry and a cyclin D1 index assigned. These results were correlated with data relating to the expression of p53 and waf1 by the same tumours. A representative subset of 54 tumours (Ta/T1 = 28; T2-T4 = 26) was also stained for Ki67 and 55 were stained for pRb. The clinical course of each patient was recorded and multivariate analyses of risk factors for tumour recurrence, stage progression and overall survival were performed. Positive staining for cyclin D1 was found in 83% of tumours. The staining pattern varied between tumours with nuclear, cytoplasmic or a combination of the two evident in different tumours. 89% of Ta/T1 and 74% of T2-T4 tumours showed nuclear staining with or without cytoplasmic staining. The median value for cyclin D1 staining was significantly higher in Ta/T1 tumours (41%) compared with T2-T4 tumours (8%, P< 0.005) with 26% of muscle-invasive tumours demonstrating absent staining. In addition, the median value for cyclin D1 staining was significantly higher in G1/G2 tumours (43%) compared with G3 tumours (14%, P< 0.005). There was a significant positive correlation between expression of cyclin D1 and waf1 expression (P< 0.0001) as well as pRb expression but not between cyclin D1 expression and expression of p53. Ki67 expression was significantly associated with increasing tumour stage (P< 0.005) and histological grade (P< 0.05) but did not correlate with cyclin D1 expression. A cyclin D1 index > or = 8% was associated with significantly better survival in those patients with muscle-invasive disease (T2-T4). In addition, there was a significantly higher progression rate for those patients with Ta/T1 disease whose tumours demonstrated cytoplasmic cyclin D1 staining. These results indicate that cyclin D1 expression is significantly higher in low-stage, well differentiated bladder tumours and strongly correlates with waf1 expression. In a multivariate analysis, cyclin D1 expression is an independent prognostic indicator of survival in those patients with muscle-invasive disease.     

The Relationships between cyclin D1 Expression and Prognosis of Non-small Cell Lung Cancer

Background and objective cyclin D1 is a member of the cyclin family, and it has been proven that it plaied an important role in tumorigenesis, invasion and metastasis. We performed a retrospective study on the cyclin D1 expression in non-small cell lung cancer (NSCLC) according to the clinical characteristics. Methods One hundred fifteen postsurgical NSCLC patients were investigated. Immunohistochemistry was used to evaluate the cyclin D1 expression. Results Overall survival was significantly lower in patients with cyclin D1-high expression of tumors than those with cyclin D1 low expression of tumors (χ2=5.132, P=0.023). In early stage patients (stage I, II), the overall survival was significantly lower in patients with cyclin D1-high expression of tumors than those with cyclin D1-low expression of tumors (χ2=6.863, P=0.009). cyclin D1 status (hazard ratio=0.630; P=0.035), differentiation (hazard ratio=0.399; P<0.001), and pTNM (hazard ratio=1.576; P<0.001) to be independent prognostic factors for NSCLC patients. Specifically, the cyclin D1 status (hazard ratio=0.188; P=0.008) was a significant prognostic factor for patients with stage I NSCLCs. Conclusion cyclin D1 expression is an independent prognosis factor for postoperative patient in stage I, II NSCLCs.     

Translation initiation complex eIF4F is a therapeutic target for dual mTOR kinase inhibitors in non-Hodgkin lymphoma

Deregulated mRNA translation has been implicated in disease development and in part is controlled by a eukaryotic initiation complex eIF4F (composed of eIF4E, eIF4G and eIF4A). We demonstrate here that the cap bound fraction from lymphoma cells was enriched with eIF4G and eIF4E indicating that lymphoma cells exist in an activated translational state. Moreover, 77% (110/142) of diffuse large B cell lymphoma tumors expressed eIF4E and this was associated with an inferior event free survival. Over-expression of wild-type eIF4E (eIF4E^WT) but not cap-mutant eIF4E (eIF4E^{cap mutant}) increased the activation of the eIF4F complex. Treatment with the active-site dual mTOR inhibitor CC214-1 reduced the level of the eIF4F complex by decreasing the cap bound fraction of eIF4G and increasing the levels of 4E-BP1. CC214-1 inhibited both the cap dependent and global protein translation. CC214-1 inhibited c-Myc, and cyclin D3 translation by decreasing polysomal fractions from lymphoma cells. Inhibition of eIF4E with shRNA further decreased the CC214-1 induced inhibition of the eIF4F complex, c-Myc, cyclin D3 translation, and colony formation. These studies demonstrate that the eIF4F complex is deregulated in aggressive lymphoma and that dual mTOR therapy has therapeutic potential in these patients.     

Cyclin D1 expression in non-small-cell lung cancers: its association with altered p53 expression, cell proliferation and clinical outcome.

Cyclin D1, like p16INK4 (p16) and retinoblastoma (RB) proteins, participates in the cell cycle control at the G1-S transition. We have previously demonstrated altered p16 and RB protein status in non-small-cell lung cancers (NSCLCs) and their potential synergistic effect with altered p53 protein on proliferative activity (Kinoshita et al (1996) Cancer Res 56: 5557-5562). In the present study, cyclin D1 expression was studied by immunohistochemistry in the same cohort of 111 resected NSCLCs as in our previous study, and the amount of the cyclin D1 gene was analysed by Southern blot analysis in 29 NSCLCs. Cyclin D1 expression was analysed in relation to the status of p53, p16 and RB proteins, and proliferative activity determined by the Ki-67 index. It was also analysed in relation to survival of 77 patients with NSCLCs which were potentially curatively resected between 1990 and 1995. We found that: (1) cyclin D1 was expressed in 13 (11.7%) of 111 NSCLCs; (2) the cyclin D1 gene was neither significantly amplified nor rearranged; (3) cyclin D1 expression significantly correlated with altered p53 protein expression (P = 0.04), whereas it did not correlate with p16 and RB protein status; (4) proliferative activity tended to be higher in cyclin D1-positive (+) tumours than in cyclin D1-negative (-) tumours, although this difference was not statistically significant (P = 0.08); and (5) patients with cyclin D1+ tumours survived longer than patients with cyclin D1- tumours (5-year survival rates, 89% and 64% respectively, by the Kaplan-Meier method; P = 0.045 by the log-rank test), and cyclin D1 expression tended to be a favourable prognostic factor (P = 0.08 in univariate analysis). These findings suggest the involvement of cyclin D1 in the development and progression of NSCLCs, their proliferative activity and clinical outcome of NSCLC patients.     

Phospho-4e-BP1 and eIF4E overexpression synergistically drives disease progression in clinically confined clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC), the most aggressive and lethal form of renal cell carcinoma accounts for over 90% of metastasis that occur following curative surgery for clinically confined disease. High relapse rates have prompted the evaluation of targeted therapies for the prevention or delay of metastatic disease in high-risk patients, with biomarkers offering significant potential to guide and improve patient management in this setting. In this current study we examined the value of the 4E-BP1/eIF4E axis for prognostic significance and risk stratification in patients with clinically confined ccRCC. This axis is a critical convergence point for many signalling pathways that are targeted by current therapies for the treatment of advanced RCC. Immunohistochemistry for phosphorylated 4E-BP1 (p4E-BP1) and total eIF4E was performed on tissue microarrays containing tumour cores from 135 patients with localised ccRCC. For both biomarkers 39% of all evaluable cores stained positive, with a strong correlation observed between the presence of p4E-BP1 and the overexpression of eIF4E within the same tumour (P = 0.005). Further, the combined expression of p4E-BP1 and eIF4E was associated with significantly worse disease-free survival of 2.9 vs 5.7 yrs compared to patients whose tumours expressed only one, or neither, of the biomarkers (P < 0.001). Cox-regression analysis confirmed the ability of the p4EBP1/eIF4E signature to independently identify high-risk patients with a Hazard Ratio of 4.2 (CI = 2.1-8.6; P < 0.001), compared to 3.3 for tumour grade 3 and 4, and 2.3 for tumour stage 3 and 4. These data show the powerful prognostic value of the p4E-BP1/eIF4E signature for potential management of patients with clinically confined ccRCC, and in addition provides insights into the possible key synergistic determinants of disease progression and treatment response.     

PSAT1 regulates cyclin D1 degradation and sustains proliferation of non‐small cell lung cancer cells

Multiple nodes in the one‐carbon metabolism pathway play important regulatory roles in cancer cell growth and tumorigenesis. The specific biological functions of metabolic enzymes in regulating the signaling pathways that are associated with tumor cell growth and survival, however, remain unclear. Our current study found that phosphoserine aminotransferase 1 (PSAT1), an enzyme catalyzing serine biosynthesis, was significantly up‐regulated in non‐small cell lung cancer (NSCLC) and was involved in the regulation of E2F activity. Loss‐ and gain‐of‐function experiments demonstrated that PSAT1 promoted cell cycle progression, cell proliferation and tumorigenesis. Mechanistic study suggested that elevated PSAT1 led to inhibition of cyclin D1 degradation and subsequently an alteration in Rb‐E2F pathway activity, which in turn enhanced G1 progression and proliferation of NSCLC cells. Moreover, phosphorylation of cyclin D1 at threonine 286 by GSK‐3β was required for PSAT1‐induced blockage of cyclin D1 degradation. We also found that the activity of p70S6K mediated the effects of PSAT1 on GSK‐3β phosphorylation and cyclin D1 degradation. We further identified that PSAT1 was over‐expressed in NSCLC and predicted poor clinical outcome of patients with the disease. Correlation analysis showed that PSAT1 expression positively correlated with the levels of phosphorylated GSK‐3β, cyclin D1 and phosphorylated Rb in NSCLC primary tumors. These findings uncover a mechanism for constitutive activation of E2F via which unrestrained cell cycle progression occurs in NSCLC and may represent a prognostic biomarker and therapeutic target.     

NF-kappa B和AP-1在非小细胞肺癌中的表达

背景与目的核因子kappa B（NF-kappa B）和激活蛋白1（AP-1）在细胞凋亡和增生过程中所起的作用逐渐被人们所认知，在肿瘤的形成过程中也扮演着重要的角色。本研究分析了NF-kappaB、AP-1在非小细胞肺癌中的表达，以明确二者之间的相互关系，并进一步研究二者对周期蛋白cyclin D1和caspase 3在非小细胞肺癌中表达的影响。方法应用Western blot检测NFkappaB、AP-1、cyclin D1和caspase 3在非小细胞肺癌中的蛋白表达，应用RT-PCR检测不同NF-kappaB和AP-1表达的肺癌组织中cyclin D1和cAspase 3的mRNA表达。应用相关分析判断NF-kappa B和AP-1的相关性。结果在45例非小细胞肺癌患者中，NF-kappaB和AP-1在肺癌组织中的表达均高于癌旁肺组织中的表达（0．6047比0．2798，P〈0．01）。在NF-kappaB和AP-1较高表达的肺癌组织中，cyclin D1蛋白表达和mRNA表达均增加（P〈0．01），而caspase 3的蛋白表达和mRNA表达减少（P（0．01）。相关分析显示NFkappaB和AP-1有明显的相关性（r=0．800，P（0．01）。结论NF-kappaB和AP-1作为转录因子可能在非小细胞肺癌的形成和发展中起重要作用。     

Inhibition of eIF4E phosphorylation reduces cell growth and proliferation in primary central nervous system lymphoma cells

The mRNA cap-binding protein eukaryotic initiation factor 4E (eIF4E) plays an important role in mRNA translation; its activity is implicated in cell growth and proliferation. In experimental models, eIF4E over-expression induces cellular transformation, tumorigenesis, and lymphomagenesis. The activity of eIF4E is regulated by the Akt/mTOR and MAPK/MAP kinase-interacting kinase-1 (MNK1) pathways. While investigating the participation of the MNK1/eIF4E signaling pathway in primary central nervous system lymphoma (PCNSL), we noted the over-expression of eIF4E and phosphorylated eIF4E (p-eIF4E) in specimens from PCNSL patients. Western blot analysis using B-cell lymphoma cell lines showed that eIF4E phosphorylation was serum-independent and was selectively inhibited by the MNK1 inhibitor. Furthermore, MNK1 inhibitor led to reduced cyclin D1 expression and caused inhibition of cell proliferation and cell death in human brain malignant lymphoma cell line (HKBML). Also, the growth of the subcutaneous HKBML xenografts in mice was inhibited by intraperitoneal administration of MNK1 inhibitor compared with mice treated with vehicle (P = 0.026). Our data suggest that in PCNSL cells eIF4E phosphorylation plays an important role in proliferation and our results identify inhibition of the MNK1/eIF4E pathway as a potential therapeutic target in patients with PCNSL.     

Cyclin D1 expression is associated with poor prognostic features in estrogen receptor positive breast cancer

Cyclins D1 and E play an important role in breast carcinogenesis. High cyclin E expression is common in hormone receptor negative and high grade aggressive breast cancer, whereas cyclin D1 in hormone receptor positive and low grade breast cancer. Experimental data has suggested that cyclin D1 and E mediate cell proliferation by different mechanisms in estrogen receptor (ER) positive and negative breast cancer. To test this hypotheses in large breast cancer material and to clarify the histopathological correlations of cyclin E and D1, especially the association with proliferation, we analyzed cyclin E and D1 immunohistochemical expression on breast tumour microarrays consisting of 1348 invasive breast cancers. High cyclin D1 expression was associated with high grade (P < 0.0005), high cyclin A (P < 0.0005) and Ki67 (P < 0.0005) expression among ER positive but with low grade (P = 0.05) and low Ki67 (P = 0.01) expression among ER negative breast cancers. Cyclin E and D1 expression correlated positively in ER positive (P < 0.0005) but had a negative correlation in ER negative tumours (P = 0.004). Cyclin E associated with high grade among all tumours (P < 0.0005). In conclusion, the findings of this study show that cyclin D1 has separate roles, and proliferation is driven by different mechanisms in ER positive and negative breast cancers.     

Cyclin D1, p53, and p21Waf1/Cip1 expression is predictive of poor clinical outcome in serous epithelial ovarian cancer.

PURPOSE: Dysregulation of cell cycle control, in particular G(1)-S-phase transition, is implicated in the pathogenesis of most human cancers, including epithelial ovarian cancer (EOC). However, the prognostic significance of aberrant cell cycle gene expression in EOC remains unclear. EXPERIMENTAL DESIGN: The expression of selected genes from the pRb pathway that regulates G(1)-S-phase progression, including cyclin D1, p16(Ink4a), cyclin E, p27(Kip1), p21(Waf1/Cip1), and p53, was examined in a consecutive series of 134 serous EOC using immunohistochemistry and the results correlated to disease outcome. RESULTS: Molecular markers predictive of reduced overall survival in univariate analysis were overexpression of cyclin D1 (P = 0.03) and p53 (P = 0.03) and reduced expression of p27(Kip1) (P = 0.05) and p21(Waf1/Cip1) (P = 0.02), with the latter three also being prognostic for a shorter progression-free interval. In addition, patients displaying overexpression of p53 with concurrent loss of p21(Waf1/Cip1) had a significantly shorter overall (P = 0.0008) and progression-free survival (P = 0.0001). On multivariate analysis, overexpression of cyclin D1 and combined loss of p21(Waf1/Cip1) in the presence of p53 overexpression were independent predictors of overall survival. Similarly, the combination of p21(Waf1/Cip1) loss and p53 overexpression was independently predictive of a shorter progression-free interval. Overexpression of p53 and cyclin E and reduced expression of p27(Kip1) and p21(Waf1/Cip1) were significantly associated with increasing tumor grade. CONCLUSIONS: This study confirms that dysregulation of cell cycle genes is common in EOC, and that aberrant expression of critical cell cycle regulatory proteins can predict patient outcome in serous EOC.     

Expression of cyclin D1a and D1b as predictive factors for treatment response in colorectal cancer

Background:

The aim of this study was to investigate the value of the cyclin D1 isoforms D1a and D1b as prognostic factors and their relevance as predictors of response to adjuvant chemotherapy with 5-fluorouracil and levamisole (5-FU/LEV) in colorectal cancer (CRC).

Methods:

Protein expression of nuclear cyclin D1a and D1b was assessed by immunohistochemistry in 335 CRC patients treated with surgery alone or with adjuvant therapy using 5-FU/LEV. The prognostic and predictive value of these two molecular markers and clinicopathological factors were evaluated statistically in univariate and multivariate survival analyses.

Results:

Neither cyclin D1a nor D1b showed any prognostic value in CRC or colon cancer patients. However, high cyclin D1a predicted benefit from adjuvant therapy measured in 5-year relapse-free survival (RFS) and CRC-specific survival (CSS) compared to surgery alone in colon cancer (P=0.012 and P=0.038, respectively) and especially in colon cancer stage III patients (P=0.005 and P=0.019, respectively) in univariate analyses. An interaction between treatment group and cyclin D1a could be shown for RFS (P=0.004) and CSS (P=0.025) in multivariate analysis.

Conclusion:

Our study identifies high cyclin D1a protein expression as a positive predictive factor for the benefit of adjuvant 5-FU/LEV treatment in colon cancer, particularly in stage III colon cancer.     

De novo diffuse large B‐cell lymphoma with a CD20 immunohistochemistry‐positive and flow cytometry‐negative phenotype: Molecular mechanisms and correlation with rituximab sensitivity

CD20 is expressed in most B-cell lymphomas and is a critical molecular target of rituximab. Some B-cell lymphomas show aberrant CD20 expression, and rituximab use in these patients is controversial. Here we show both the molecular mechanisms and the clinical significance of de novo diffuse large B-cell lymphomas (DLBCL) that show a CD20 immunohistochemistry (IHC)-positive and flow cytometry (FCM)- negative (IHC[+]/FCM[−]) phenotype. Both IHC and FCM using anti-CD20 antibodies L26 and B1, respectively, were analyzed in 37 of the 106 cases of de novo DLBCL; 8 (22%) of these cases were CD79a(+)/CD20(+) with IHC and CD19(+)/CD20(−) with FCM. CD20 (MS4A1) mRNA expression was significantly lower in IHC(+)/FCM(−) cells than in IHC(+)/FCM(+) cells (P = 0.0005). No genetic mutations were detected in MS4A1 promoter and coding regions. Rituximab-mediated cytotoxicity in the CDC assay using IHC(+)/FCM(−) primary cells was significantly lower than in IHC(+)/FCM(+) cells (P < 0.05); however, partial effectiveness was confirmed. FCM using rituximab detected CD20 more efficiently than B1. No significant difference was observed between IHC(+)/FCM(−) and IHC(+)/FCM(+) patients in overall survival (P = 0.664). Thus, lower expression of CD20 mRNA is critical for the CD20 IHC(+)/FCM(−) phenotype. Lower CD20 expression with FCM does not rule out rituximab use in these patients if expression is confirmed with IHC. FCM using rituximab may be more informative than B1 for predicting rituximab effectiveness in IHC(+)/FCM(−) cases.