Cyclin D1 overexpression and prognosis in colorectal adenocarcinoma

Wortmannin Inhibits Cell Growth and Induces Apoptosis in Colorectal Cancer Cells by Suppressing the PI3K/AKT Pathway

BACKGROUND

Colorectal cancer (CRC) remains a significant contributor to mortality, often exacerbated by metastasis and chemoresistance. Novel therapeutic strategies are imperative to enhance current treatments. The dysregulation of the PI3K/Akt signaling pathway is implicated in CRC progression. This study investigates the therapeutic potential of Wortmannin, combined with 5-fluorouracil (5-FU), to target the PI3K/Akt pathway in CRC.

METHODS

Anti-migratory and antiproliferative effects were assessed through wound healing and MTT assays. Apoptosis and cell cycle alterations were evaluated using Annexin V/Propidium Iodide Apoptosis Assay. Wortmannin's impact on the oxidant/antioxidant equilibrium was examined via ROS, SOD, CAT, MDA, and T-SH levels. Downstream target genes of the PI3K/AKT pathway were analyzed at mRNA and protein levels using RTPCR and western blot, respectively.

RESULTS

Wortmannin demonstrated a significant inhibitory effect on cell proliferation, modulating survivin, cyclinD1, PI3K, and p-Akt. The PI3K inhibitor attenuated migratory activity, inducing E-cadherin expression. Combined Wortmannin with 5-FU induced apoptosis, increasing cells in sub-G1 via elevated ROS levels.

CONCLUSION

This study underscores Wortmannin's potential in inhibiting CRC cell growth and migration through PI3K/Akt pathway modulation. It also highlights its candidacy for further investigation as a promising therapeutic option in colorectal cancer treatment.

Prognostic Significance of Cyclin D1 Expression in Small Intestinal Adenocarcinoma

Cyclin D1, a critical cyclin-dependent kinase (CDK) 4/6-dependent regulator of G1/S transition, has attracted much interest as a therapeutic target. The cyclin D1 expression in small intestinal adenocarcinomas (SIACs) has not yet been comprehensively studied, owing to the rarity of this tumor. We investigated the clinicopathological and prognostic significance of the cyclin D1 expression in 232 surgically resected primary SIACs through a multi-institutional study. A high expression of cyclin D1 (cyclin D1High) was detected in 145 SIAC cases (63%), which was significantly higher than that in normal small intestinal mucosa (11%). Cyclin D1High was more commonly found in SIACs with a lower T-category and disease stage and KRAS mutation and predicted better patient survival. Multivariate analysis revealed that cyclin D1High, the absence of retroperitoneal seeding and lymphovascular invasion, and the lower N-category were identified as independent prognostic indicators for patients with SIACs. Specifically, cyclin D1High affected patient survival in the lower stage group (stages I and II). In conclusion, cyclin D1 was commonly overexpressed in SIACs, and cyclin D1High acted as a favorable prognostic indicator in patients with SIACs. These findings in SIACs may, thus, be important to further comprehend the mechanism of cyclin D1 in carcinogenesis and to strategize appropriate patient therapies.

Prognostic Biomarkers of Cell Proliferation in Colorectal Cancer (CRC): From Immunohistochemistry to Molecular Biology Techniques

Colorectal cancer (CRC) is one of the most common and severe malignancies worldwide. Recent advances in diagnostic methods allow for more accurate identification and detection of several molecular biomarkers associated with this cancer. Nonetheless, non-invasive and effective prognostic and predictive testing in CRC patients remains challenging. Classical prognostic genetic markers comprise mutations in several genes (e.g., APC, KRAS/BRAF, TGF-β, and TP53). Furthermore, CIN and MSI serve as chromosomal markers, while epigenetic markers include CIMP and many other candidates such as SERP, p14, p16, LINE-1, and RASSF1A. The number of proliferation-related long non-coding RNAs (e.g., SNHG1, SNHG6, MALAT-1, CRNDE) and microRNAs (e.g., miR-20a, miR-21, miR-143, miR-145, miR-181a/b) that could serve as potential CRC markers has also steadily increased in recent years. Among the immunohistochemical (IHC) proliferative markers, the prognostic value regarding the patients' overall survival (OS) or disease-free survival (DFS) has been confirmed for thymidylate synthase (TS), cyclin B1, cyclin D1, proliferating cell nuclear antigen (PCNA), and Ki-67. In most cases, the overexpression of these markers in tissues was related to worse OS and DFS. However, slowly proliferating cells should also be considered in CRC therapy (especially radiotherapy) as they could represent a reservoir from which cells are recruited to replenish the rapidly proliferating population in response to cell-damaging factors. Considering the above, the aim of this article is to review the most common proliferative markers assessed using various methods including IHC and selected molecular biology techniques (e.g., qRT-PCR, in situ hybridization, RNA/DNA sequencing, next-generation sequencing) as prognostic and predictive markers in CRC.

Multiomics Study of a Novel Naturally Derived Small Molecule, NSC772864, as a Potential Inhibitor of Proto-Oncogenes Regulating Cell Cycle Progression in Colorectal Cancer

Colorectal cancer (CRC) is one of the most prevalent malignant tumors, and it contributes to high numbers of deaths globally. Although advances in understanding CRC molecular mechanisms have shed significant light on its pathogenicity, current treatment options, including combined chemotherapy and molecular-targeted agents, are still limited due to resistance, with almost 25% of patients developing distant metastasis. Therefore, identifying novel biomarkers for early diagnosis is crucial, as they will also influence strategies for new targeted therapies. The proto-oncogene, c-Met, a tyrosine kinase that promotes cell proliferation, motility, and invasion; c-MYC, a transcription factor associated with the modulation of the cell cycle, proliferation, apoptosis; and cyclin D1 (CCND1), an essential regulatory protein in the cell cycle, all play crucial roles in cancer progression. In the present study, we explored computational simulations through bioinformatics analysis and identified the overexpression of c-Met/GSK3β/MYC/CCND1 oncogenic signatures that were associated with cancer progression, drug resistance, metastasis, and poor clinical outcomes in CRC. We further demonstrated the anticancer activities of our newly synthesized quinoline-derived compound, NSC772864, against panels of the National Cancer Institute's human CRC cell lines. The compound exhibited cytotoxic activities against various CRC cell lines. Using target prediction tools, we found that c-Met/GSK3β/MYC/CCND1 were target genes for the NSC772864 compound. Subsequently, we performed in silico molecular docking to investigate protein-ligand interactions and discovered that NSC772864 exhibited higher binding affinities with these oncogenes compared to FDA-approved drugs. These findings strongly suggest that NSC772864 is a novel and potential antiCRC agent.

Prognostic Potential of Cyclin D1 Expression in Colorectal Cancer

Cyclin D1 is mainly known as an oncogenic driver in cancers, and the dysregulated cyclin D1/cyclin-dependent kinase (CDK) 4/6 axis is considered an attractive target for cancer therapy. Recent studies have reported that tumors respond to therapeutic interventions targeting altered cyclin D1 expression via application of the CDK4/6 inhibitor. However, the prognostic and therapeutic contributions of cyclin D1 to colorectal cancer (CRC) remain controversial. Herein, we assessed the associations between cyclin D1 expression and clinicopathological factors, including patients' overall survival (OS) and recurrence-free survival (RFS), in 495 surgically resected primary CRCs. We also examined previous studies for cyclin D1 in CRCs. High expressions of cyclin D1 (cyclin D1^High) was observed in 389 CRC cases (78.6%). Cyclin D1^High consistently predicted better patient OS and RFS in CRCs. Based on multivariate analysis, cyclin D1^High and young age of patients remained as independent prognosticators of higher OS rate, whereas cyclin D1^High, females, chemotherapy, absence of nodal metastasis, and lower T-category remained as independent prognosticators of better RFS. Cyclin D1 is commonly overexpressed in CRCs, and its expression can be used as a favorable prognostic indicator in patients with CRCs; this may be important for predicting responses to subsequent CDK4/6 inhibitors.

AMP-kinase inhibitor dorsomorphin reduces the proliferation and migration behavior of colorectal cancer cells by targeting the AKT/mTOR pathway

Colorectal cancer (CRC) is among the leading causes of cancer-related mortality, despite extensive efforts in the identification of new treatment options. Hence, there is a need for the development of novel agents with therapeutic potential in treatment of CRC. Dorsomorphin has demonstrated antiproliferative activity against different malignancies. Here we have investigated the pharmaceutical potential of dorsomorphin in two-dimensional and three-dimensional cell-culture models of CRC. The antiproliferative, antimigratory, apoptotic activity and effect of this agent on cell cycle was evaluated by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, wound healing assay, and flow cytometry, respectively, while the expression of genes involved in Wnt/Pi3K pathways was assessed at mRNA and/or proteins by reverse transcription polymerase chain reaction (RT-PCR) or western blot. Dorsomorphin inhibited CRC cell growth by modulating the cyclinD1, surviving and p-Akt. This agent was able to reduce the migratory behaviors of CRC cells, compared to control cells, through perturbation of E-cadherin. Also our data showed that dorsomorphin enhanced the percentage of the cells in sub-G1 and induced apoptosis in both late/early stages, as detected by annexin V. Also the regulatory effect of dorsomorphin on oxidant/antioxidant balance was assessed by cellular reactive oxygen species (ROS) generation. In particular, these data showed that dorsomorphin markedly increased the ROS production in CRC cells. Our finding demonstrated that dorsomorphin antagonizes cell growth and migration, through perturbation of Akt/mTOR/Wnt pathways in CRC, supporting further studies on the therapeutic potential of this novel anticancer agent in treatment of CRC.

POFUT1 promotes colorectal cancer development through the activation of Notch1 signaling

Copy number variations (CNVs) are key drivers of colorectal cancer (CRC). Our previous studies revealed that protein O-fucosyltransferase 1 (POFUT1) overexpression is driven by CNVs during CRC development. The potential role and underlying mechanisms of POFUT1 in CRC were not investigated. In this study, we analyzed the expression of POFUT1 in CRC from cosmic and TCGA databases and confirmed that POFUT1 is highly expressed in CRC. We used well characterized CRC cell lines, including SW620 and HCT116 to establish a model POFUT1 knockdown cell line. Using these cells, we investigated the role of POFUT1 in CRC. Our data revealed that silencing POFUT1 in CRC cells inhibits cell proliferation, decreases cell invasion and migration, arrests cell cycle progression, and stimulates CRC cell apoptosis in vitro. We further demonstrate that POFUT1 silencing dramatically suppresses CRC tumor growth and transplantation in vivo. We additionally reveal new mechanistic insights into the role of POFUT1 during CRC, through demonstrating that POFUT1 silencing inhibits Notch1 signaling. Taken together, our findings demonstrate that POFUT1 is a tumor activating gene during CRC development, which positively regulates CRC tumor progression through activating Notch1.

Genetic markers of recurrence in colorectal cancer

Colorectal cancer (CRC) worldwide belongs to one of the most frequent cancers affecting both genders. Surgery and 5-fluorouracil-based adjuvant chemotherapy are recommended for patients with high-risk stage II and stage III colon carcinoma. Mutations of genes encoding for specific proteins may have an impact on the time to recurrence. These proteins act over specific signaling pathways, are implicated in metabolic processes and regulate the cell cycle. Though many retrospective studies show strong associations between genetic mutations and the clinical outcome of patients with CRC, currently no validated biomarkers are used in clinical routine settings. Therefore, large prospective validation studies should be carried out in order to strengthen the position of genetic mutations in personalized treatment of patients with CRC.

Antiproliferative and apoptotic-inducing potential of ellagic acid against 1,2-dimethyl hydrazine-induced colon tumorigenesis in Wistar rats

Colon cancer remains one of the major worldwide causes of cancer-related morbidity and mortality in Western countries and is increasingly common in Asia. Ellagic acid (EA), a major component of polyphenol possesses attractive remedial features. The aim of this study is to divulge the potential effect of EA during 1,2-dimethyl hydrazine (DMH)-induced colon cancer in male Wistar albino rats. The rats were segregated into four groups: group I, control rats; group II, rats received EA (60 mg/kg b.wt./day, orally); rats in group III, induced with DMH (20 mg/kg b.wt.) subcutaneously for 15 weeks; DMH-induced group IV rats were initiated with EA treatment. Colon of the rats treated with DMH exhibited higher glycoconjugates and proliferation index such as elevated expressions of argyrophilic nucleolar organizing regions (AgNORs), proliferating cell nuclear antigen (PCNA), cyclin D1, matrix metalloproteins (MMP-2 and -9), and mast cells. DMH induction also increased phase I-metabolizing enzymes with simultaneous decrease in the phase II detoxifying enzymes. In contrast, dietary administration of EA significantly (p < 0.05) down regulated the proliferation index and restored back the levels of biotransformation enzymes. The carcinogenic insult also altered the expression of pro-apoptotic protein p53, whereas dietary EA administration significantly (p < 0.01) up regulates p53 expression to further induce apoptotic pathway. Ultrastructural changes in colon were also in accord with the above aberrations. Overall findings suggested that the suppression of colon cancer by EA in vivo involves inhibition of cell proliferation, activation of apoptosis, and efficient detoxification.

Influence of anthropometric factors on tumour biological characteristics of colorectal cancer in men and women: a cohort study

Background

Obesity is a well established risk factor of colorectal cancer (CRC), but how body size influences risk of colorectal cancer defined by key molecular alterations remains unclear. In this study, we investigated the relationship between height, weight, body mass index (BMI), waist- and hip circumference, waist-hip ratio (WHR) and risk of CRC according to expression of beta-catenin, cyclin D1, p53 and microsatellite instability status of the tumours in men and women, respectively.

Methods

Immunohistochemical expression of beta-catenin, cyclin D1, p53 and MSI-screening status was assessed in tissue microarrays with tumours from 584 cases of incident CRC in the Malmö Diet and Cancer Study. Six anthropometric factors: height, weight, BMI, waist- and hip circumference, and WHR were categorized by quartiles of baseline measurements and relative risks of CRC according to expression of beta-catenin, cyclin D1, p53 and MSI status were calculated using multivariate Cox regression models.

Results

High height was associated with risk of cyclin D1 positive, and p53 negative CRC in women but not with any investigative molecular subsets of CRC in men. High weight was associated with beta-catenin positive, cyclin D1 positive, p53 negative and microsatellite stable (MSS) tumours in women, and with beta-catenin negative and p53 positive tumours in men. Increased hip circumference was associated with beta-catenin positive, p53 negative and MSS tumours in women and with beta-catenin negative, cyclin D1 positive, p53 positive and MSS tumours in men. In women, waist circumference and WHR were not associated with any molecular subsets of CRC. In men, both high WHR and high waist circumference were associated with beta-catenin positive, cyclin D1 positive and p53 positive tumours. WHR was also associated with p53 negative CRC, and waist circumference with MSS tumours. High BMI was associated with increased risk of beta-catenin positive and MSS CRC in women, and with beta-catenin positive, cyclin D1 positive and p53 positive tumours in men.

Conclusions

Findings from this large prospective cohort study indicate sex-related differences in the relationship between obesity and CRC risk according to key molecular characteristics, and provide further support of an influence of lifestyle factors on different molecular pathways of colorectal carcinogenesis.

Developmental cis-regulatory analysis of the cyclin D gene in the sea urchin Strongylocentrotus purpuratus

Cyclin D genes regulate the cell cycle, growth and differentiation in response to intercellular signaling. While the promoters of vertebrate cyclin D genes have been analyzed, the cis-regulatory sequences across an entire cyclin D locus have not. Doing so would increase understanding of how cyclin D genes respond to the regulatory states established by developmental gene regulatory networks, linking cell cycle and growth control to the ontogenetic program. Therefore, we conducted a cis-regulatory analysis on the cyclin D gene, SpcycD, of the sea urchin, Strongylocentrotus purpuratus, during embryogenesis, identifying upstream and intronic sequences, located within six defined regions bearing one or more cis-regulatory modules each.

Inhibitory effect of a standardized pomegranate fruit extract on Wnt signalling in 1, 2-dimethylhydrazine induced rat colon carcinogenesis

BACKGROUND

De-regulation of Wnt signalling is increasingly being implicated in both experimental and human carcinogenesis including colon cancer.

AIMS

Our goal was to identify possible dietary agents that block Wnt signalling as a step toward investigating new strategies for suppression of colon cancer. Pomegranate extract has emerged as an intriguing candidate due to its polyphenolic content.

METHODS

We used a 1,2-dimethylhydrazine dihydrochloride (DMH)-induced rat colon carcinogenesis model to investigate the expression pattern of the main key players in Wnt signalling by reverse transcription polymerase chain reaction (RT-PCR) analysis.

RESULTS

Our results showed that many Wnt-target genes, e.g., Wnt5a, frizzled receptor (FRZ)-8, β-catenin, T cell factor/lymphoid enhancer binding protein (Tcf4/Lef1), c-myc and cyclin D1, were up-regulated whereas adenomatous polyposis coli (APC) and axin1 exhibited down-regulation in colonic tissues of our DMH-colon cancer group compared with the normal group. Standardized pomegranate extract minimised all the aberrant alterations observed in the studied Wnt genes in colonic tissues of the DMH+pomegranate group as compared with the DMH-induced colon cancer group. This effect was also confirmed by the normalization of survival rate, inhibition of tumour incidence and a reduction of serum tumour marker carcinoembryonic antigen (CEA) level. Histopathological observations provided supportive evidence for the biochemical and molecular analyses.

CONCLUSIONS

Standardized pomegranate extract holds great promise in the field of colon cancer prevention by dietary agents.

Female-specific rectal carcinogenesis in cyclin D1b transgenic mice

Human cyclin D1 generates two major isoforms via alternative splicing: cyclin D1a and cyclin D1b. Cyclin D1b is hardly expressed in normal tissues but is frequently expressed in certain types of cancer tissues. To clarify the oncogenic potential of cyclin D1b variant, we developed cyclin D1b transgenic (Tg) mice and analyzed their phenotypes. We detected rectal tumors in 63% (15/24) of the female Tg mice. All rectal tumors had the histological characteristics similar to human sessile serrated adenoma/polyps (SSA/Ps). Adenocarcinomas were also found in 53% (8/15) of the rectal tumors, suggesting that these adenocarcinomas originated from the SSA/P-like lesions. No rectal tumors were found in the ovariectomized female cyclin D1b Tg mice (0/10), indicating that ovarian hormones played a critical role in rectal carcinogenesis in these Tg mice. Both phosphorylation of Erk, without activating MEK, and expression of estrogen receptor β were elevated in the rectal tumors of female cyclin D1b Tg mice compared with normal rectums of female wild-type mice. In addition, we established a cell line, D1bTgRT, derived from a rectal cancer of female Tg mouse. Small interfering RNA-induced cyclin D1b knockdown in this cell line suppressed Erk phosphorylation, anchorage-independent growth, cell invasiveness and tumorigenicity in nude mice. In humans, expression of cyclin D1b messenger RNA was detected in 17% (1/6) of colorectal cancer cell lines and 9.7% (3/31) of colorectal cancer tissues. Taken together, these results indicate that cyclin D1b expression contributes to the female- specific rectal carcinogenesis in mouse model.

The cyclin D1 (CCND1) rs9344 G>A polymorphism predicts clinical outcome in colon cancer patients treated with adjuvant 5-FU-based chemotherapy

Recent evidence indicates a potential prognostic and predictive value for germline polymorphisms in genes involved in cell cycle control. We investigated the effect of cyclin D1 (CCND1) rs9344 G>A in stage II/III colon cancer patients and validated the findings in an independent study cohort. For evaluation and validation set, a total of 264 and 234 patients were included. Patients treated with 5-fluorouracil-based chemotherapy, carrying the CCND1 rs9344 A/A genotype had significantly decreased time-to-tumor recurrence (TTR) in univariate analysis and multivariate analysis (hazard ratio (HR) 2.47; 95% confidence interval (CI) 1.16-5.29; P=0.019). There was no significant association between CCND1 rs9344 G>A and TTR in patients with curative surgery alone. In the validation set, the A allele of CCND1 rs9344 G>A remained significantly associated with decreased TTR in univariate and multivariate analyses (HR 1.94; 95% CI 1.05-3.58; P=0.035). CCND1 rs9344 G>A may be a predictive and/or prognostic biomarker in stage II/III colon cancer patients, however, prospective trials are warranted to confirm our findings.

Prevention and Treatment of Colorectal Cancer by Natural Agents From Mother Nature

Colorectal cancer (CRC) is the third most commonly diagnosed cancer in the United States after cancers of the lung and the breast/prostate. While the incidence of CRC in the United States is among the highest in the world (approximately 52/100,000), its incidence in countries in India is among the lowest (approximately 7/100,000), suggesting that lifestyle factors may play a role in development of the disease. Whereas obesity, excessive alcohol consumption, a high-calorie diet, and a lack of physical activity promote this cancer, evidence indicates that foods containing folates, selenium, Vitamin D, dietary fiber, garlic, milk, calcium, spices, vegetables, and fruits are protective against CRC in humans. Numerous agents from "mother nature" (also called "nutraceuticals,") that have potential to both prevent and treat CRC have been identified. The most significant discoveries relate to compounds such as cardamonin, celastrol, curcumin, deguelin, diosgenin, thymoquinone, tocotrienol, ursolic acid, and zerumbone. Unlike pharmaceutical drugs, these agents modulate multiple targets, including transcription factors, growth factors, tumor cell survival factors, inflammatory pathways, and invasion and angiogenesis linked closely to CRC. We describe the potential of these dietary agents to suppress the growth of human CRC cells in culture and to inhibit tumor growth in animal models. We also describe clinical trials in which these agents have been tested for efficacy in humans. Because of their safety and affordability, these nutraceuticals provide a novel opportunity for treatment of CRC, an "old age" disease with an "age old" solution.

Cyclin D1 G870A polymorphism and risk of colorectal cancer: a case control study

The present study aimed to analyse the role of cyclin D1 A870G polymorphism in modulating the susceptibility to colorectal cancer (CRC) in the Kashmiri population. The genotype distribution of the cyclin D1 gene in 130 CRC cases in comparison with 160 healthy controls was investigated. No direct significant association between cyclin D1 genotypes and CRC was observed; however, the AG and AA genotypes were found to be associated with an increased risk of CRC compared to the GG genotype, with an almost 2-fold increase in OR. This study suggests that the cyclin D1 polymorphism is associated with an increased risk of CRC in the Kashmiri population.

Cyclin D1 expression in colorectal cancer is a favorable prognostic factor in men but not in women in a prospective, population-based cohort study

Background

Although colorectal cancer (CRC) is generally not considered to be a hormone-dependent malignancy, several sex-related differences in incidence, molecular characteristics and survival have been reported. Epidemiological studies have consistently shown that increased exposure to female sex hormones is associated with a lower risk of CRC in women, and cyclin D1, an important downstream effector in estrogen-mediated signaling, is commonly activated in CRC. In this study, we analyzed the prognostic significance of cyclin D1 expression in CRC, with particular reference to sex-related differences, in tumors from a large, prospective, population-based cohort.

Methods

Using tissue microarrays and immunohistochemistry, the fraction and intensity of cyclin D1 expression was evaluated in 527 incident CRC cases from the Malmö Diet and Cancer Study. The χ² and Spearman's rho (ρ) tests were used for comparison of cyclin D1 expression and relevant clinicopathological characteristics. Kaplan-Meier analysis and Cox proportional hazards modeling were used to assess the effect of cyclin D1 expression on cancer-specific survival (CSS) in univariate and multivariate analysis, adjusted for established prognostic factors.

Results

Cyclin D1 intensity was significantly lower in male compared with female CRC (P = 0.018). In the full cohort, cyclin D1 expression was associated with a significantly prolonged CSS (hazard ratio (HR) = 0.69; 95% CI 0.49 to 0.96, P = 0.026) but subgroup analysis according to gender revealed a strongly accentuated prognostic effect of cyclin D1 in male CRC (HR = 0.48; 95% CI 0.31 to 0.74, P < 0.001), which was in contrast to female CRC, where cyclin D1 was not prognostic (HR = 1.05; 95% CI 0.62 to 1.78, P = 0.864) (P_interaction = 0.024). The prognostic value of cyclin D1 was not retained in multivariate analysis, either in the full cohort or in male CRC.

Conclusions

Cyclin D1 expression is strongly associated with prolonged survival in male CRC. These findings not only support an important role for cyclin D1 in colorectal carcinogenesis, but also add further weight to the accumulating evidence that CRC is indeed a hormone-dependent malignancy, for which prognostic and treatment-predictive molecular biomarkers should be evaluated differently in women and men.

Curcumin sensitizes human colorectal cancer to capecitabine by modulation of cyclin D1, COX-2, MMP-9, VEGF and CXCR4 expression in an orthotopic mouse model

Because of the poor prognosis and the development of resistance against chemotherapeutic drugs, the current treatment for advanced metastatic colorectal cancer (CRC) is ineffective. Whether curcumin (a component of turmeric) can potentiate the effect of capecitabine against growth and metastasis of CRC was investigated. The effect of curcumin on proliferation of CRC cell lines was examined by mitochondrial dye-uptake assay, apoptosis by esterase staining, nuclear factor-kappaB (NF-kappaB) by electrophoretic mobility shift assay and gene expression by Western blot analysis. The effect of curcumin on the growth and metastasis of CRC was also examined in orthotopically implanted tumors in nude mice. In vitro, curcumin inhibited the proliferation of human CRC cell lines, potentiated capecitabine-induced apoptosis, inhibited NF-kappaB activation and suppressed NF-kappaB-regulated gene products. In nude mice, the combination of curcumin and capecitabine was found to be more effective than either agent alone in reducing tumor volume (p = 0.001 vs. control; p = 0.031 vs. capecitabine alone), Ki-67 proliferation index (p = 0.001 vs. control) and microvessel density marker CD31. The combination treatment was also highly effective in suppressing ascites and distant metastasis to the liver, intestines, lungs, rectum and spleen. This effect was accompanied by suppressed expression of activated NF-kappaB and NF-kappaB-regulated gene products (cyclin D1,c-myc, bcl-2, bcl-xL, cIAP-1, COX-2, ICAM-1, MMP-9, CXCR4 and VEGF). Overall, our results suggest that curcumin sensitizes CRC to the antitumor and antimetastatic effects of capecitabine by suppressing NF-kappaB cell signaling pathway.

Predictive molecular markers for colorectal cancer patients with resected liver metastasis and adjuvant chemotherapy

BACKGROUND & AIMS

The aims of the study were to evaluate the predictive value of 8 candidate molecular markers for colorectal cancer (CRC) patients receiving hepatic arterial infusion (floxuridine [FUDR] and dexamethasone) and systemic irinotecan (CPT11) post resection of liver metastasis.

METHODS

RNA was extracted from microdissected tumor cells of fixed and embedded specimens of resected liver metastases (94 cases) and analyzed by quantitative reverse-transcription polymerase chain reaction (RT-PCR) for thymidine phosphorylase, dihydropyrimidine dehydrogenase, thymidylate synthase, uridine phosphorylase, uridine/cytidine (monophospho)kinase, Bcl-2 related protein, Cyclin-D1, and Survivin expression. Uni- and multivariate statistical analyses and an explorative hierarchical clustering analysis of quantitative RT-PCR data were performed for overall survival and recurrent disease.

RESULTS

After adjustment for multiple clinicopathologic parameters, none of the markers were significantly associated with overall survival (except, marginally, Cyclin-D1; P = .06) or extrahepatic recurrence. However, high Survivin (P = .03) and Cyclin-D1 (P = .05) levels were predictive for hepatic recurrence. Hierarchical cluster analysis identified 7 of 94 patients associated with lower hepatic recurrence (P < .001). This patient group was characterized by low Cyclin-D1 and Survivin messenger RNA levels, both genes also clustering together.

CONCLUSIONS

Cyclin-D1 and Survivin messenger RNA analyzed by standardized, quantitative RT-PCR are predictive markers for CRC patients receiving hepatic arterial infusion (FUDR/dexamethasone) and systemic CPT11 post resection of liver metastasis. Moreover, our exploratory hierarchical cluster analysis of quantitative RT-PCR data supports its potential as an application to define clinically relevant patient subgroups.

Superior nuclear receptor selectivity and therapeutic index of methylprednisolone aceponate versus mometasone furoate

Although introduced more than 50 years ago, topical glucocorticoids are still the first line therapy for many inflammatory skin disorders such as atopic eczema, contact dermatitis and many others. Recently, significant improvements have been made to optimize the ratio of desired to unwanted effects. While with early compounds such as triamcinolone, topical side effects such as skin atrophy and telangiectasias can be observed rather frequently, newer drugs such as methylprednisolone aceponate or mometasone furoate have a significantly improved therapeutic index. The present study compared these two modern topical glucocorticoids, which possess the highest therapeutic index currently found, in terms of nuclear receptor selectivity in vitro and induction of the most important local side effects (skin atrophy and telangiectasias) in a relevant rodent model in vivo. We demonstrate that methylprednisolone aceponate displays higher specificity in nuclear receptor binding compared with mometasone furoate. Methylprednisolone aceponate was also markedly superior in terms of minimizing induction of skin atrophy or telangiectasias when compared with mometasone furoate. Based on these observations, methylprednisolone aceponate is expected to have a greater therapeutic index as compared with mometasone furoate, at least in the test systems used here. The degree to which this observation may translate into a clinical setting requires confirmation.

Short-term growth in children with eczema during treatment with topical mometasone furoate and tacrolimus

BACKGROUND

Treatment with topical glucocorticoids in children with atopic eczema may be associated with systemic adverse effects, such as suppression of growth.

AIM

To asses if treatment with topical mometasone furoate 0.1% or topical tacrolimus 0.1% affects short-term growth in children with atopic eczema. Primary outcome measures were lower leg growth rates measured by knemometry.

METHODS

Twenty 5- to 12-year-old prepubertal children with atopic eczema were included in a randomised, investigator-blind crossover study with five periods: two treatment periods, a run in, a wash out and a run out. All periods were of 2-week duration. The subjects applied mometasone furoate ointment 0.1% once daily during one treatment period and tacrolimus ointment 0.1% twice daily during the other treatment period.

RESULTS

As compared to run in mean lower leg growth rate during mometasone furoate and tacrolimus treatment was reduced by 0.09 and 0.06 mm/week, respectively, (F = 1.12, p = 0.35). Consistently, no statistically significant effects on urine levels of eosinophil protein X and crossed-linked N-telopeptides were detected.

CONCLUSION

Treatment with mometasone furoate or tacrolimus does not affect short-term growth in children with mild to moderate atopic eczema.

Cyclin D1 Gene G870A Polymorphism Predicts Response to Neoadjuvant Radiotherapy and Prognosis in Rectal Cancer

PURPOSE

To investigate whether CCND1 genetic variations associated with a constitutive nuclear protein may influence either the pathologic response to preoperative RT or the prognosis in a series of rectal cancer patients.

METHODS AND MATERIALS

Seventy rectal cancer patients treated by neoadjuvant radiotherapy were included in the study. CCND1 exon 5 mutations were screened, and the G870A polymorphism was assessed for correlation with clinical variables, tumor response, and patient outcome.

RESULTS

No exon 5 mutation was found. Concerning the G870A polymorphism, the A/A variant was significantly associated with radiosensitivity (p = 0.022). Moreover, patients harboring the A allele were correlated with a lower risk of local failure (p = 0.017). Also, combination of the G870A polymorphism with the post-therapeutic lymph node status allowed the elaboration of a prognostic index, which accurately distinguished subgroups of patients with predictable recurrence-free (p = 0.003) and overall (p = 0.044) survival.

CONCLUSIONS

Although CCND1 exon 5 mutations are rare in rectal cancer, G870A polymorphism is a frequent variation that may predict radiosensitivity and prognosis.

The Significance of Ki-67 Proliferative Index and Cyclin D1 Expression of Dysplastic Nevi in the Biologic Spectrum of Melanocytic Lesions

Familial acquired dysplastic nevi carry a risk for the development of melanoma. However, the results in various studies regarding the significance of sporadic dysplastic nevi as a precursor of malignant melanoma (MM), are controversial. The aim of this study is to investigate cyclin D1 expression and Ki67 proliferative index in a group of melanocytic lesions to address the biologic significance of sporadic dysplastic nevi in the progression of melanocytic lesions. Formalin-fixed paraffin-embedded material from 21 common melanocytic nevi, 42 dysplastic nevi, and 17 primary cutaneous MMs were examined. Standard streptavidin-biotin immunoperoxidase method was used for immunostaining with cyclin D1 and Ki-67 antibody. Nuclear cyclin D1 immunostaining was scored and Ki-67 proliferative index was calculated. Cyclin D1 expression was significantly higher in melanoma than those in other lesions. However, there was no significant difference between dysplastic nevi and common melanocytic nevi in terms of cyclin D1 expression. Ki-67 index was significantly higher in dysplastic nevi compared with common melanocytic nevi and to melanoma compared with dysplastic nevi. There was a significant positive correlation between cyclin D1 expression and Ki-67 proliferative index for each group. The present study indicates significant differences in cyclin D1 expressions and Ki-67 indices among melanocytic lesions. We think that dysplastic nevi are biologically separate from common melanocytic nevi in terms of proliferative activity. Additionally, our results suggest that cyclin D1 expression may be related to malignant phenotype and is associated with high proliferation rate in MM.

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.

A pathologic complete response of rectal cancer to preoperative combined-modality therapy results in improved oncological outcome compared with those who achieve no downstaging on the basis of preoperative endorectal ultrasonography

BACKGROUND

Preoperative combined-modality therapy (CMT) is the preferred treatment for locally advanced rectal cancer (endorectal ultrasonography [ERUS] T3-4, N1, or clinically bulky) and achieves a pathologic complete response (pCR) in 4% to 33% of patients. However, the prognostic significance of pCR remains unclear.

METHODS

A prospectively collected database was queried to identify 200 patients with locally advanced disease treated from 1992 to 2002. The pCR group was defined as having no evidence of viable tumor on pathologic analysis. The no-downstaging group was defined as no difference between the pre-CMT ERUS stage and the pathologic stage. Those achieving some downstaging but not pCR were excluded. Patients were treated with CMT (5040 cGy of radiation and 5-fluorouracil-based chemotherapy) followed by surgery, and 51 (85%) in the pCR group and 129 (92%) in the no-downstaging group (P = .1) received postoperative chemotherapy. Recurrence-free survival (RFS) and overall survival (OS) were determined by using the Kaplan-Meier method.

RESULTS

The median follow-up was 38.6 months (range, 18.2-124.9 months). The pCR (n = 60) and control (n = 140) groups were similar in age (P = .6), sex (P = .4), distance of the tumor from the anal verge (P = .3), pre-CMT ERUS stage (P = .2), and comorbidities (P = .2). The 5-year RFS was 96% and 54% in the pCR and control groups, respectively (P < .00001); the 5-year OS was 90% and 68% (P = .009). Sphincter-preservation rates were higher in the pCR group (P = .01).

CONCLUSIONS

Rectal cancer patients with pCR after preoperative CMT have improved RFS, OS, and sphincter preservation compared with patients without downstaging. Because pCR seems to be associated with better outcome, an understanding of the factors governing the response to CMT should be pursued.

A comparative study of the expression of Wnt-1, WISP-1, survivin and cyclin-D1 in colorectal carcinoma

BACKGROUND AND AIMS

It is well accepted that activation of Wnt signalling occurs in colorectal carcinoma (CRC), but the correlation amongst the various proteins involved in primary tumours are still unclear. The expression of the inducer of this pathway, Wnt-1, and the downstream effectors, WISP-1, cyclin-D1 and survivin proteins, was compared in a series of CRC tissues with the apparently normal adjacent tissues to determine the relationship of these proteins.

PATIENTS AND METHODS

Formalin-fixed, paraffin-embedded tissue samples of 47 CRCs surgically resected at the Kuala Lumpur Hospital (KLH) between 1999 and 2000 were used. Immunohistochemical staining with monoclonal antibodies against cyclin-D1 and survivin and polyclonal antibodies against Wnt-1 and WISP-1 was performed. Results of immunohistochemistry were analysed for correlation between biomolecules and histopathological data of the patients.

RESULTS

Of the 47 CRCs, 26 (55.3%), 15 (31.9%), 5 (10.6%) and 28 (59.6%) of the tumours exhibited positivity for Wnt-1, WISP-1, cyclin D1 and survivin, respectively. A lower percentage of the 40 apparently normal adjacent tissues were found to be positive for Wnt-1 (7, 17.5%), WISP-1 (+/-5, 12.5%) and survivin (13, 32.5%), but cyclin D1 was not detected in any of them. Interestingly, the total scores of Wnt-1, WISP-1 and survivin were significantly higher in CRC tissues (p=0.001, 0.034 and 0.044, respectively). Using the Spearman rank correlation test, a positive linear relationship was found between total Wnt-1 score with total WISP-1 score (rho=0.319, p=0.003) and total survivin score (rho=0.609, p=or<0.001). The expression of WISP-1 in the CRC tissues was found to be positively correlated with patients older than 60 years old (p=0.011). In addition, nuclear cyclin-D1 expression was found to be associated with poorly differentiated CRC tissues (p<0.001, Table 5) and right-sided CRC tumour (p=0.019, Table 6). Total WISP-1 score was associated with well-differentiated CRC tissues (p=0.029).

CONCLUSIONS

Overexpression and interplay between Wnt-1, WISP-1, survivin and cyclin-D1 may play a role in tumorigenesis, possibly by promoting cell cycle checkpoint progression, accelerating cell growth and inhibiting apoptosis. Our data may provide useful information towards the search for potent therapeutic targets towards the development of novel treatment strategies for CRC.

Cyclin D1 (CCND1) A870G gene polymorphism modulates smoking-induced lung cancer risk and response to platinum-based chemotherapy in non-small cell lung cancer (NSCLC) patients

PURPOSE

The cyclin D1 (CCND1) A870G gene polymorphism is linked to the outcome in patients with resectable non-small cell lung cancer (NSCLC). Here, we investigated the impact of this polymorphism on smoking-induced cancer risk and clinical outcome in patients with NSCLC stages I-IV.

METHODS

CCND1 A870G genotype was determined by polymerase chain reaction (PCR) and restriction fragment length polymorphism analysis (RFLP) of DNA extracted from blood. The study included 244 NSCLC patients and 187 healthy control subjects.

RESULTS

Patient characteristics were: 70% male, 77% smokers, 43% adenocarcinoma, and 27% squamous cell carcinoma. Eighty-one percent of the patients had stages III-IV disease. Median age at diagnosis was 60 years and median survival was 13 months. Genotype frequencies of patients and controls both conformed to the Hardy Weinberg equilibrium. The GG genotype significantly correlated with a history of heavy smoking (>or=40 py, P=0.02), and patients with this genotype had a significantly higher cigarette consumption than patients with AA/AG genotypes (P=0.007). The GG genotype also significantly correlated with tumor response or stabilization after a platinum-based first-line chemotherapy (P=0.04). Survival analysis revealed no significant differences among the genotypes.

CONCLUSION

Evidence was obtained that the CCND1 A870G gene polymorphism modulates smoking-induced lung cancer risk. Further studies are required to explore the underlying molecular mechanisms and to test the value of this gene polymorphism as a predictor for platinum-sensitivity in NSCLC patients.

Cyclin D1 and Rb protein expression and their correlation with prognosis in patients with colon cancer

Background

Cyclin D1 plays a major role as a potential contributor to the multistep process of oncogenesis; nevertheless its prognostic significance in colon cancer has already been examined in a few studies and needs to be further delineated. The aim of this study was to assess the expression of cyclin D1 and pRb and to correlate them with tumor histological stage and grade, proliferative capacity (Ki-67 labeling index) and clinical parameters, in order to delineate their impact on prognosis.

Methods

One hundred and eleven patients, who underwent surgical resection of the colon for colon cancer constituted the group of our study. The immunohistochemical expression of cyclin D1, Rb and Ki-67 proteins was examined and correlated with clinico-pathological parameters and survival.

Results

The 5-years survival rate of patients presenting cyclin D1 positive tumors was 54%, while that of cyclin D1 negative ones was 67% (P = > 0.05). The survival rate of patients with pRb positive tumors was similar to that of pRb negatine ones. Significant association was observed between Ki-67 and cyclin D1 positivity (P = 0.045). Univariate analysis revealed worse survival in advanced stage patients presenting cyclin D1 positive tumors (P = 0.025). Additionally, the survival of patients aging less than 70 years old was correlated to cyclin D1 positivity (P = 0.009). Multivariate survival analysis revealed statistical significance for stage and hepatic metastasis.

Conclusion

Even though cyclin D1 and pRb have not disclosed any clear association with shorter survival, cyclin D1 positivity may be a useful predictor of subgroup patients with colon cancer being in advanced stage and early age.

Expression of p27 in residual rectal cancer after preoperative chemoradiation predicts long-term outcome

BACKGROUND

Compared with surgery alone, preoperative radiotherapy and 5-fluorouracil-based chemotherapy (combined-modality therapy; CMT) improves outcomes in patients with locally advanced rectal cancer. Although numerous studies have focused on identifying molecular markers of prognosis in the primary rectal cancer before CMT, our aim was to identify markers of prognosis in residual rectal cancer after preoperative CMT.

METHODS

Sixty-seven patients with locally advanced (T3-4 and/or N1) rectal cancer were treated with preoperative radiotherapy (median, 5040 cGy) with or without 5-fluorouracil-based chemotherapy. Residual tumor in the resected specimen, available for 52 patients, was analyzed for tumor-node-metastasis stage, lymphovascular and/or perineural invasion, and immunohistochemical expression of p27, p21, p53, Ki-67, retinoblastoma gene, cyclin D1, and bcl-2. Recurrence-free survival (RFS) was determined by the Kaplan-Meier method and compared by the log-rank test.

RESULTS

With a median follow-up of 69 months, the overall 5-year RFS was 74%. RFS was significantly worse for patients with positive p27 expression (P = .005), T3-4 tumors (P = .02), and positive lymph nodes (P = .04) in the irradiated specimen. On multivariate analysis, positive p27 expression remained an independent negative prognostic factor for RFS (P = .04). None of the other proteins was significantly associated with RFS.

CONCLUSIONS

Our results indicate that positive p27 expression in rectal cancer after preoperative chemoradiation is an independent negative predictor of RFS. Expression of p27 in the residual rectal cancer may therefore identify patients with disease likely to be refractory to standard therapy and for whom investigational approaches should be strongly considered.

Constitutive activation of Stat3 signaling pathway in human colorectal carcinoma

AIM: Signal transducers and activators of transcription (STATs) are a family of transcription factors activated in response to cytokines and growth factors. Constitutive activation of Stat3 has been observed in a growing number of tumor-derived cell lines, as well as tumor specimens from human cancers. The purpose of this study was to investigate the expression of p-Stat3, activated form of Stat3, and its downstream mediators including cyclin D1 and Bcl-x_L in colorectal carcinoma (CRC), and to explore the possible mechanism of Stat3 signaling pathway in the tumorigenesis of colorectal carcinoma.

METHODS: Tissue samples from 45 patients of primary colorectal carcinoma were selected for studying Stat3 signaling pathway protein expression. Western blot analysis was used to measure the expression of p-Stat3, cyclin D1, and Bcl-x_L proteins in colorectal carcinomas. Furthermore, the expression patterns of these proteins were analyzed for their distribution at the cellular level by immunohistochemical staining of the tissues.

RESULTS: Protein levels of p-Stat3, cyclin D1, and Bcl-x_L were increased in colorectal carcinomas compared with adjacent normal mucosae (P < 0.05). Elevated levels of p-Stat3 were correlated with the nodal metastasis and the stage (P < 0.05). Overexpression of cyclin D1 was associated with the nodal metastasis (P < 0.05). There was also a significant correlation between the expressions of p-Stat3 and cyclin D1 (r = 0.382, P < 0.05).

CONCLUSION: Constitutive activation of Stat3 may play an important role in the tumorigenesis of colorectal carcinoma, and the detailed mechanism of Stat3 signaling pathway in CRC deserves further investigation.

The importance of cyclin D1 and Ki67 expression on the biological behavior of pancreatic adenocarcinomas

The aim of this study was to evaluate the role of cyclin D1 and Ki67 proteins involved in cell-cycle control as a prognostic factor in pancreatic carcinomas. We examined formalin-fixed, paraffin-embedded material from 59 pancreatic adenocarcinomas, for which appropriate clinical and prognostic data were available. The standard streptavidin biotin immunoperoxidase method was used for immunostaining with cyclin D1 and Ki67. The extent of positive nuclear and cytoplasmic cyclin D1 staining was graded semiquantitatively. Ki67 reactivity was quantified and expressed as the percentage of stained nuclei. Staining with cyclin D1 and Ki67 was compared with histopathological prognostic features, and their relation with survival was also tested statistically. Patients whose tumors were cyclin D1-positive showed perineural invasion significantly more frequently than did patients with cyclin D1-negative tumors at the immunohistochemical level. In addition, tumors with lymphatic vessel invasion and without showed a significant difference in terms of cytoplasmic cyclin D1 staining. Ki67 indices were statistically different in stage groups. There was a significant and direct correlation between Ki67 index and nuclear cyclin D1 staining scores. No relation with survival was found. Our results suggest that cell-cycle proteins do not directly affect the prognosis of patients with pancreatic adenocarcinoma. Conversely, cyclin D1-positive tumors tend to have perineural invasion more frequently. In addition, lymph vessel invasion is another factor related to cyclin D1 reactivity of the cells. Ki67 indices differ statistically in stage groups.

Chemosensitivity testing and test-directed chemotherapy in human pancreatic cancer

Human pancreatic cancer is a devastating disease with poor prognosis. In many cases it is diagnosed at stages in which a complete resection is not possible. However, even after complete resection most tumors recur. Therefore, several chemotherapeutic strategies have been developed, so far, with little impact on the clinical outcome. Because one of the hallmarks of human pancreatic cancer is its general resistance to chemotherapeutic agents, it seems important to develop strategies to individualize chemotherapy and to render cells more sensitive to chemotherapeutic agents. In this summary we describe our methods of in vitro chemosensitivity testing using the human tumor colony-forming assay for pancreatic cancer in comparison with other solid tumors and describe how the in vitro results influence chemotherapy. Furthermore, we point out new developments of mRNA quantitation of chemoresistance target enzymes based on real-time PCR, which may help in the future to individualize chemotherapy of pancreatic cancer. Finally, we present results of studies of cyclin D1 inhibition. Suppression of cyclin D1 by cyclin D1 antisense mRNA expression was associated with growth inhibition and an increase in chemosensitivity to fluoropyrimidines and platinum compounds. Because human pancreatic cancers are relatively chemoresistant and material for chemosensitivity testing with the human tumor colony-forming assay (HTCA) is in most cases difficult to obtain, future investigations should aim at the development of methods requiring only very small samples to analyzemarkers of chemosensitivity. Our results further suggest that chemotherapy in combination with strategies to increase chemosensitivity may be a reasonable regimen for the treatment of human pancreatic cancer in the future.

Linking cyclins to transcriptional control

Cell cycle activation is coordinated by D-type cyclins which are rate limiting and essential for the progression through the G1 phase of the cell cycle. D-type cyclins bind to and activate the cyclin-dependent kinases Cdk4 and Cdk6, which in turn phosphorylate their downstream target, the retinoblastoma protein Rb. Upon Rb phosphorylation, the E2F transcription factors activate the expression of S-phase genes and thereby induce cell cycle progression. The raise of cyclin D levels in early G1 also serves to titrate Kip/Cip proteins away from cyclinE/Cdk2 complexes, further accelerating cell cycle progression. Therefore, cyclin D plays essential roles in the response to mitogens, transmitting their signal to the Rb/E2F pathway. Surprisingly, cyclin D1-deficient animals are viable and have developmental abnormalities limited to restricted tissues, such as retina, the nervous system and breast epithelium. This observation, combined with several other studies, have raised the possibility that cyclin D1 may have new activities that are unrelated to its function as a cdk regulatory subunit and as regulator of Rb. Effectively, cyclin D has been reported to have transcriptional functions since it interacts with several transcription factors to regulate their activity. Most often, this effect does not rely on the kinase function of Cdk4, indicating that this function is probably independent of cell cycle progression. Further extending its role in gene regulation, cyclin D interacts with histone acetylases such as P/CAF or NcoA/SRC1a but also with components of the transcriptional machinery such as TAF(II)250. Therefore, these studies suggest that the functions of cyclin D might need to be reevaluated. They have established a new cdk-independent role of cyclin D1 as a transcriptional regulator, indicating that cyclin D1 can act via two different mechanisms, as a cdk activator it regulates cell cycle progression and as a transcriptional regulator, it modulates the activity of transcription factors.

Analysis of key cell-cycle checkpoint proteins in colorectal tumours

Aberrations in the components of cell-cycle checkpoints are a common feature of many tumours and several have been shown to have prognostic significance in colorectal cancer. In this study, seven components of cell-cycle control [cyclin D1, retinoblastoma (pRb), p21, p27, p16, p53, and proliferating cell nuclear antigen (PCNA)] were examined in a large series of well-characterized colorectal adenocarcinomas using immunohistochemistry to ascertain co-regulation and influence on survival. The majority (92%) of the tumours had abnormal staining of > or =2 cell-cycle control factors. Expression of cyclin D1 protein was correlated with both p21 (p<0.001) and p27 (p=0.033), suggesting co-regulation of these proteins in colorectal tumours. Only cyclin D1 (p=0.048) and p53 (p=0.025) were directly associated with PCNA levels, suggesting a more important role in the proliferative capacity of tumour cells. Significant associations between cell cycle-related proteins and clinicopathological data were observed: cyclin D1 and p53 proteins were correlated with patient age (p=0.042 and p<0.001, respectively) and p53 (p=0.01) and p21 (p=0.024) proteins were associated with tumour site. Expression of cyclin D1 protein was the only protein examined that was related to improved outcome in these patients (p=0.0266), but it was not an independent predictor of survival. These results suggest that loss of control of cell-cycle checkpoints is a common occurrence in colorectal tumours and may be an important therapeutic target.

P21 (WAF1) expression in colorectal cancer: correlation with P53 and cyclin D1 expression, clinicopathological parameters and prognosis

P21 (WAF1), P53 and cyclin D1 belong to the cell cycle-regulating family of proteins, and the loss of activity of proteins P53 and P21 (WAF1) seems to be one of the most important regulatory mechanisms of carcinogenesis in colorectal cancer. The purpose of this study was to assess the relationship between P21 (WAF1), P53 and cyclin D1 immunoreactivity, and to evaluate the prognostic significance of their expression. Tissue sections from 122 paraffin-embedded colorectal carcinomas were immunostained with monoclonal antibodies. Positivity for P21 (WAF1) was found in 48 cases (39%), positivity for P53 in 96 cases (70%) and positivity for cyclin D1 in all the cases (100%). Statistical analyses revealed a statistically significant inverse correlation between P53 and P21 (WAF1)-immunopositivity and between P21 (WAF1)-immunopositivity and the degree of cyclin D1-immunopositivity, as well as an inverse correlation between P21 (WAF1) expression and clinical stage. In univariate analysis, down-regulation of P21 (WAFI) expression was associated with poor prognosis, but multivariate analysis did not confirm its independent prognostic significance. In Cox's analysis only regional lymph node invasion and hepatic metastases were proven as independent prognostic parameters. Our investigation results suggest that in colorectal cancer, the induction of P21 (WAF1) may occur mostly in a P53-dependent pathway. P21 (WAF1), as the main cyclin-dependent kinase (CDK)-inhibitor, may also inhibit the activity of cyclins such as cyclin D1.

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.

Subcellular localisation of cyclin D1 protein in colorectal tumours is associated with p21(WAF1/CIP1) expression and correlates with patient survival

We investigated the expression of the cell cycle regulatory proteins cyclin D1 and p21(WAF1/CIP1) (p21) in human colorectal carcinomas using immunohistochemistry. Cyclin D1 was not detected in normal colonic epithelium; however, expression was observed in 74/126 (58.7%) of the tumour samples studied. Protein was detected in the nucleus in 22/126 (17.4%) and exclusively in the cytoplasm in 52/126 (41.3%) tumours. Nuclear expression of cyclin D1 was associated with poorly differentiated tumours (p = 0.035) and was more common in right- than in left-sided tumours (p = 0.005). Tumours displaying either, expression of cytoplasmic, (p = 0.05, HR 0.56, 95% CI 0.31-1.0) or nuclear (p = 0.021, HR 0.24, 95% CI 0.07-0.81) cyclin D1 were associated with improved patient survival compared with tumours negative for cyclin D1. p21 protein was strongly expressed mainly in the upper crypts of normal colonic epithelial cells, but in 63/126 (50%) of the tumour samples studied p21 expression was absent. Patients with tumours in which >50% of cells expressed p21 had improved survival compared to patients whose tumours were negative or had < or =50% of cells expressing p21 (p = 0.06, HR 0.33, 95% CI 0.1-1.0). We also observed a significant association between cyclin D1 subcellular localisation and p21 expression: 21/22 (95.5%) tumours expressing cyclin D1 in the nucleus also expressed p21, whereas only 17/52 (32.7%) of the tumours displaying exclusive cytoplasmic cyclin D1 staining were positive for p21 (p < 0.001). These data highlight the significance of exclusive cytoplasmic expression of cyclin D1 in colorectal cancer and lend support to recent in vitro studies suggesting that p21 protein may modulate the subcellular localisation of the cyclin D1 protein. Thus, deregulated expression of the cyclin D1 and p21 proteins are important in colorectal tumourigenesis and have implications for patient prognosis.

Combined analysis of p53 and RB pathways in epithelial ovarian cancer

Disruptions of the p16-CDK4/cyclin D1-pRb pathway (RB pathway) and the p14ARF-MDM2-p53 pathway (p53 pathway) are important mechanisms in the development of human malignancies. In this study, we investigated RB and p53 pathways in 46 epithelial ovarian cancers (EOCs). In the RB pathway, 16 (34.8%) of 46 cases had p16 gene alterations or loss of expression. The deletion of the p16 gene was a rare event. In 7 cases, we observed methylation in the 5'CpG island in the promoter region of the p16 gene. Abnormal expressions of pRb and CDK4/cyclin D1 were 10.9% and 30.4%, respectively. In the p53 pathway, 10 (21.7%) of 46 cases had p14ARF gene alterations or abnormal expression. In 4 cases, methylation in the 5'CpG island in the promoter region of the p14ARF gene was present. MDM2 overexpression was a rare event. Thirty-six (78.3%) of 46 patients had p53 gene alterations or expression. In our studied cases, p14ARF abnormalities were independent of p16 abnormalities. Abnormal RB and p53 pathways were present in 60.9% and 80.4% of cases, respectively. In conclusion, disruptions of p53 and RB pathways are frequent events and the inverse correlations were present between the abnormality of p16 and p14ARF in EOCs.

Expression and clinical significance of the G1-S modulators in intrahepatic cholangiocellular carcinoma

OBJECTIVE

To elucidate the clinical roles of G1-S modulators in cholangiocellular carcinoma (CCC).

METHODS

We performed immunohistochemistry using antibodies against the retinoblastoma gene product (pRb), p16, p21, p27, p53 and cyclin D1 for 41 cases of CCC as well as normal bile ducts.

RESULTS

The p27 labeling index (LI) was significantly higher in cases without lymph node metastasis than in normal bile ducts, but it decreased greatly in cases with lymph node metastasis. It was inversely related to the Ki-67 LI. The p16 LI also showed a relationship with lymph node metastasis, but not with the Ki-67 LI. The p21 LI was even higher in poorly differentiated cases and showed a direct relationship with the Ki-67 LI, although it is a negative regulator of the cell cycle. pRb expression did not correlate with any clinicopathological features. Cyclin D1 overexpression was more frequently observed in cases with poor or moderate differentiation and with lymph node metastasis. Cyclin D1 overexpression and aberrant p53 expression showed direct relationships with the Ki-67 LI.

CONCLUSIONS

These results suggest that in CCC: (1) p27 expression reflects the biological character of the carcinoma and may regulate its progression; (2) cyclin D1 plays a crucial role in cell cycle progression, and (3) aberrant p53 expression has some effect on CCC cell proliferating activity.

Expression of cell-cycle regulator p27 is correlated to the prognosis and ER expression in breast carcinoma patients

Cell cycle inhibitor p27 is variously expressed in breast carcinoma. A possible association between the expression of p27 and the prognosis of breast carcinoma remains to be elucidated. We investigated the expression of p27 and cyclin D1 in a retrospective series of 216 breast carcinomas immunohistochemically. Expression of p27 (p27 LI) ranged from 0 to 93.6% (median 62.4%). There was a positive association between p27 LI and cyclin D1 (p < 0.01) and between p27 LI and ER (p < 0.0001). In the combination study of p27 LI and cyclin D1 expression, the patients classified as low p27 LI/cyclin D1 negative had a poorer prognosis than those in other categories. p27 was identified as an independent prognostic factor by the multivariate Cox proportional hazard model with a relative risk of death of disease of 4.1 (p < 0.05; vs. high p27 LI compared to the median). Assessment of p27 expression and examination of both p27 LI and cyclin D1 expression may identify breast carcinoma patients who would benefit from adjuvant therapy.

Cyclin D1 protein expression and gene polymorphism in colorectal cancer. Aberdeen Colorectal Initiative

Cyclin D1 is a key cell cycle regulatory protein, the expression and subcellular localization of which is often altered in human tumor cells. A common A/G single nucleotide polymorphism (A870G) in exon 4 of the cyclin D1 gene, CCND1, is associated with the presence of 2 distinct mRNA transcripts for this G1/S regulatory protein, and CCND1 genotype has been related to prognosis in lung cancer and head and neck carcinoma. We have investigated both the expression of cyclin D1 protein and the CCND1 A870G polymorphism in 100 colorectal cancer patients. Immunohistochemistry demonstrated cyclin D1 protein expression in 55% of tumors, and while the absence of cyclin D1 protein was not associated with outcome (p=0.81), high levels of protein expression (>50% of tumor cells expressing cyclin D1) correlated with significantly shortened overall survival (p=0.01). Using polymerase chain reaction restriction fragment length polymorphism analysis, we determined the frequency of each genotype and found that CCND1 genotype was not related to overall survival (p>0.05). In addition, genotype was unrelated to the level of expression and localization of cyclin D1 protein, as well as other key G1/S checkpoint proteins (p21, p27, p53, retinoblastoma) and tumor proliferation markers (proliferating cell nuclear antigen). However, higher levels of p27, and to a lesser extent p21, were associated with reduced cytoplasmic cyclin D1 protein (p=0.029 and p=0.054, respectively). In conclusion, we have demonstrated that high levels of cyclin D1 protein expression are related to outcome in colorectal cancer; however, the CCND1 A870G polymorphism is unrelated to either cyclin D1 protein expression or patient survival.

Alterations of cell cycle regulators in localized synovial sarcoma: A multifactorial study with prognostic implications

Genetic alterations of cell cycle regulators are thought to represent uncommon and possible secondary events in sarcomas characterized by recurrent chromosomal translocations. The present study investigates this hypothesis on synovial sarcoma (SS), assessing the frequency of expression and possible clinical implications of detecting alterations in critical cell cycle regulatory proteins. A homogeneous cohort of 49 patients with localized SS, restricted to the extremity and with available long-term follow-up information, was selected from our files. We focused our study on molecules involved in the G1 checkpoint and G1-S transition, including cyclins D1 and E, p21(WAF1), p27(Kip1), mdm2, p53, and Ki67. A cutoff point of 10% immunoreactive tumor cell nuclei was selected to define a positive phenotype for any given marker, except for Ki67. High Ki67 proliferative index was considered when >/=20% tumor cells displayed nuclear immunoreactivity. Biphasic SS were analyzed, taking into account separately the expression of these proteins in the spindle and glandular components. Disease specific survival was modeled using the Kaplan-Meier method with log rank test and Cox regression. The cohort of patients analyzed included 23 females and 26 males, and the histological type distribution was 35 monophasic and 14 biphasic SS. The median follow-up for survivors was 53 months, with a 5-year disease-specific survival of 63% and a metastatic disease-free survival of 40%. The positive phenotypes identified for the different markers studied were as follows: cyclin D1, 59%; cyclin E, 29%; p21, 51%; p27, 69%; mdm2, 59%; p53, 16%; and Ki67, 59%. We observed that positive p53, cyclin E, and high Ki67 proliferative index were correlated with survival, but only Ki67 and p53 were independent variables for prognostication. The present study suggests that alterations of cell cycle regulators are more common events in SS than originally thought. p53 overexpression could be of use as a marker together with a high Ki67 proliferative index, in identifying a subset of SS patients with increased risk of tumor relapse.

Cell cycle-associated proteins in melanotic neuroectodermal tumor of infancy

OBJECTIVE

The purpose of the present study was to compare the immunohistochemical expression of cell cycle-associated proteins in neuroblastic and melanocytic cell populations of melanotic neuroectodermal tumor of infancy.

STUDY DESIGN

Three cases of melanotic neuroectodermal tumor of infancy were selected. The immunohistochemical expression of MDM-2, p53, proliferating cell nuclear antigen, cyclin D1, and cyclin A was assessed through use of the streptavidin-biotin-peroxidase complex technique.

RESULTS

Positive immunostaining for MDM-2, proliferating cell nuclear antigen, cyclin D1, and cyclin A was occasionally observed in the large melanin-containing epithelioid cells.

CONCLUSIONS

These data suggest that MDM-2 expression may be important for the development of melanotic neuroectodermal tumor of infancy and that the melanocytic cell population, not the neuroblastic one, is the proliferative component of the tumor.

Expression of cell-cycle regulatory proteins cyclin D1, cyclin E, and their inhibitor p21 WAF1/CIP1 in gastric cancer

The expression and prognostic role of cyclin D1, cyclin E, and p21 (WAF1/CIP1) were immunohistochemically investigated in 413 curatively resected gastric carcinomas. p21 was expressed in 65.4 per cent (n=270), cyclin D1 in 23.7 per cent (n=98), and cyclin E in 13.6 per cent ( n=56) of the tumours. The expression of p21, cyclin D1, and cyclin E was positively associated with the papillary or tubular type of the WHO classification, as well as with the intestinal type according to the Lauren classification. No significant correlation could be found between the expression of p21, cyclin D1 and cyclin E and the parameters pT category, lymph node involvement, and blood vessel and lymphatic vessel invasion. Concerning survival, no prognostic impact of p21, cyclin D1, and cyclin E expression could be verified, even when different subgroups of patients were analysed separately according to the pT and pN category as well as to the Lauren classification. The present data suggest that neither cyclin D1, cyclin E nor their inhibitor p21 can predict the survival of gastric cancer patients, nor is their immunohistochemical detection a suitable tool for identifying subgroups of patients who may be at higher risk.

Expression of cyclins A and D and p21(waf1/cip1) proteins in renal cell cancer and their relation to clinicopathological variables and patient survival

We have studied 118 renal cell carcinomas to analyse the expressions of cyclins A and D1 and p21(waf1/cip1), and their relationship to clinical and histopathological parameters as well as to clinical outcome. Cyclins A and D1 and cyclin-dependent kinase inhibitor p21 (waf1/cip1) were not expressed in normal renal tissue. Staining signals of cyclin D1 and p21(waf1/cip1) were always nuclear but cyclin A was also expressed in the cytoplasm of the tumour cells. The mean (range) fractions of cyclin A, cyclin D1 and p21(waf1/cip1)-positive tumour cells were 2.2% (range 0-20%), 23.3% (range 0-90%) and 6.8% (range 0-70%) respectively. The expression of cyclin A was related to venous invasion, high nuclear grade, high mitotic rate, high Ki-67 and high PCNA expressions (P < or = 0.006 for all). The expression of cyclin D1 was linked with age over 65 years, low nuclear grade and high p53 expression (P < or = 0.05 for all). An inverse correlation was present between p21(waf1/cip1) and cyclin D1 (P = 0.011). Cyclin A predicted survival in the entire study group (P = 0.0014), in T1-4/N0-2/M0 (P = 0.0007) and in T1-2/N0/M0 tumours (P = 0.0007). Cyclin A was also a powerful predictor of disease-free survival in T1-4/N0/M0 (P = 0.0027) tumours (P = 0.0007). Cyclin D1 and p21(waf1/cip1) were not significantly related to survival or disease-free survival in any of the groups. In the entire material the independent prognostic factors were the presence of distant metastases (relative risk (RR) 5.16, P < 0.001), T category (RR 2.68, P < 0.001), Ki-67 expression (RR 1.02, P = 0.026) and cyclin A expression (RR 1.12, P = 0.001). The independent predictors in T1-4/N0/M0 tumours were T-category (RR 2.67, P = 0.001) and cyclin A (RR 1.21, P < 0.001), and in T1-2/N0/M0 tumours the only significant predictor was cyclin A (RR 1.19, P = 0.0002). In renal cell carcinoma, cyclin A is a powerful and independent prognostic factor in all clinical stages of the disease, whereas cyclin D1 and p21(waf1/cip1) have no prognostic value.

Cell cycle regulators: mechanisms and their role in aetiology, prognosis, and treatment of cancer

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Expression and prognostic roles of the G1-S modulators in hepatocellular carcinoma: p27 independently predicts the recurrence

Expression of cell-cycle modulators at the G1-S boundary, retinoblastoma gene product (pRb), p21, p16, p27, p53, cyclin D1, and cyclin E was investigated with 104 hepatocellular carcinomas (HCC), as well as 90 of their adjacent noncancerous lesions and 9 normal liver control specimens. The labeling indices (LI) of pRb, p21, p16, and p27 were higher in HCC lesions than in the adjacent noncancerous lesions and normal controls. Especially, p27 LI in noncancerous lesions was significantly higher than that in normal livers (P =.011). Aberrant p53 expression and cyclin D1 and E overexpression were observed exclusively in HCC lesions. pRb was positive in 85.6% of the HCC cases and was not related to any clinicopathological parameters. The p21 LI was generally low (average, 5.5 +/- 9.8). Although a negative regulator, p21 LI was higher in cases with intrahepatic metastasis (P =.0359). The p16 LI was significantly decreased (P =.0121) in cases with advanced stage. p27 LI was significantly decreased in cases with portal invasion (P =.0409), poor differentiation (P <.0001), larger size (P =.0421), and intrahepatic metastasis (P =.0878, borderline significance). On the other hand, aberrant p53 expression showed positive relationships with poor differentiation (P =.0004) and Ki-67 LI (P =. 0047). Cyclin D1 overexpression was found in 32.6% of the cases and occurred more frequently in those with high Ki-67 LI (P =.0032), pRb expression (P =.0202), poor differentiation (P =.0612, borderline significance), and intrahepatic metastasis (P =.0675, borderline significance). Cyclin E was overexpressed in 35.5% and had positive relationships with Ki-67 LI (P =.0269) and stage (P =.0125). In univariate analysis, cases with p27 LI < 50 (P =.0004), cyclin D1 overexpression (P =.0041), and cyclin E overexpression (P =.0572, borderline significance) showed poorer outcomes for disease-free survival (DFS). In multivariate analysis, p27 expression could be recognized as an independent prognostic marker for DFS. These findings suggest that in HCC: 1) p27 is active against HCC progression in early phases and, possibly, hepatocarcinogenesis as a negative regulator and can be a novel prognostic marker for DFS; and 2) cyclin D1 predominantly works for cell-cycle progression at the G1-S boundary.