Cyclin D1 guanine/adenine 870 polymorphism with altered protein expression is associated with genomic instability and aggressive clinical biology of esophageal adenocarcinoma

MYEOV with High Frequencies of Mutations in Head and Neck Cancers Facilitates Cancer Cell Malignant Behaviors

Cancer driver genes (CDGs) and the driver mutations disrupt the homeostasis of numerous critical cell activities, thereby playing a critical role in tumor initiation and progression. In this study, integrative bioinformatics analyses were performed based on a series of online databases, aiming to identify driver genes with high frequencies of mutations in head and neck cancers. Higher myeloma overexpressed (MYEOV) genetic variation frequency and expression level were connected to a poorer prognosis in head and neck cancer patients. MYEOV was dramatically upregulated within head and neck tumor samples and cells. Consistently, MYEOV overexpression remarkably enhanced the aggressiveness of head and neck cancer cells by promoting colony formation, cell invasion, and cell migration. Conversely, MYEOV knockdown attenuated cancer cell aggressiveness and inhibited tumor growth and metastasis in the oral orthotopic tumor model. In conclusion, MYEOV is overexpressed in head and neck cancer, with greater mutation frequencies correlating to a poorer prognosis in head and neck cancer patients. MYEOV serves as an oncogene in head and neck cancer through the promotion of tumor cell colony formation, invasion, and migration, as well as promoting tumor growth and metastasis in the oral orthotopic tumor model.

Single Nucleotide Polymorphisms Associated with Prostate Cancer Progression: A Systematic Review

BACKGROUND

New biomarkers of progression in patients with prostate cancer (PCa) are needed to improve their classification and clinical management. This systematic review investigated the relationship between single nucleotide polymorphisms (SNPs) and PCa progression.

METHODS

A keyword search was performed in Pubmed, EMBASE, Scopus, Web of Science, and Cochrane for publications between 2007 and 2022. We included articles with adjusted and significant associations, a median follow-up greater than or equal to 24 months, patients taken to radical prostatectomy (RP) as a first therapeutic option, and results presented based on biochemical recurrence (BCR).

RESULTS

In the 27 articles selected, 73 SNPs were identified in 39 genes, organized in seven functional groups. Of these, 50 and 23 SNPs were significantly associated with a higher and lower risk of PCa progression, respectively. Likewise, four haplotypes were found to have a significant association with PCa progression.

CONCLUSION

This article highlights the importance of SNPs as potential markers of PCa progression and their possible functional relationship with some genes relevant to its development and progression. However, most variants were identified only in cohorts from two countries; no additional studies reproduce these findings.

Combined epigenetic and immunotherapy for blastic and classical mantle cell lymphoma

Classical MCL (cMCL) constitutes 6-8% of all B cell NHL. Despite recent advances, MCL is incurable except with allogeneic stem cell transplant. Blastic mantle cell lymphoma (bMCL) is a rarer subtype of cMCL associated with an aggressive clinical course and poor treatment response, frequent relapse and poor outcomes. We treated 13 bMCL patients with combined epigenetic and immunotherapy treatment consisting of vorinostat, cladribine and rituximab (SCR). We report an increased OS greater than 40 months with several patients maintaining durable remissions without relapse for longer than 5 years. This is remarkably better then current treatment regimens which in bMCL range from 14.5-24 months with conventional chemotherapy regimens. We demonstrate that the G/A870 CCND1 polymorphism is predictive of blastic disease, nuclear localization of cyclinD1 and response to SCR therapy. The major resistance mechanisms to SCR therapy are loss of CD20 expression and evasion of treatment by sanctuary in the CNS. These data indicate that administration of epigenetic agents improves efficacy of anti-CD20 immunotherapies. This approach is promising in the treatment of MCL and potentially other previously treatment refractory cancers.

Computational analysis of Cyclin D1 gene SNPs and association with breast cancer

CCND1 encodes for Cyclin D1 protein and single-nucleotide polymorphisms (SNPs) can modulate its activity. In the present study, the impact of CCND1 SNPs on structure and/or function of Cyclin D1 protein using in silico tools was investigated. Our analysis revealed only one splice site SNP (c.1988+5G<A) can effect CCND1 function. Subsequently, 78 out of 169 missense variants were predicted as pathogenic by Polyphen2, SIFT, PROVEAN, SNPs&GO, and PANTHER, and 4/78 missense SNPs were further evaluated because these four SNPs were found to be reside in highly conserved region of Cyclin D1. However, they did not show any major impact on tertiary structure and domain of Cyclin D1 but overall R15S and A190S has displayed a significant diseased phenotype and an altered molecular mechanism predicted by MutPred, FATHMM, SNPeffect, SNAP2, and PredictSNP. Consistently, A190S, R179L, and R15S may also cause a decrease in stability of Cyclin D1 anticipated by I-Mutant, HOPE and SNP effect. Furthermore, the Kaplan–Meier plotter has explained that high expression of CCND1 is associated with less survival rate of breast cancer patients. Altogether our study suggests that c.1988+5G<A, R15S, R179L, and A190S SNPs could directly or indirectly destabilize Cyclin D1.

A systematic review and meta-analysis of prognostic biomarkers in resectable esophageal adenocarcinomas

Targeted therapy is lagging behind in esophageal adenocarcinoma (EAC). To guide the development of new treatment strategies, we provide an overview of the prognostic biomarkers in resectable EAC treated with curative intent. The Medline, Cochrane and EMBASE databases were systematically searched, focusing on overall survival (OS). The quality of the studies was assessed using a scoring system ranging from 0-7 points based on modified REMARK criteria. To evaluate all identified prognostic biomarkers, the hallmarks of cancer were adapted to fit all biomarkers based on their biological function in EAC, resulting in the features angiogenesis, cell adhesion and extra-cellular matrix remodeling, cell cycle, immune, invasion and metastasis, proliferation, and self-renewal. Pooled hazard ratios (HR) and 95% confidence intervals (CI) were derived by random effects meta-analyses performed on each hallmarks of cancer feature. Of the 3298 unique articles identified, 84 were included, with a mean quality of 5.9 points (range 3.5-7). The hallmarks of cancer feature 'immune' was most significantly associated with worse OS (HR 1.88, (95%CI 1.20-2.93)). Of the 82 unique prognostic biomarkers identified, meta-analyses showed prominent biomarkers, including COX-2, PAK-1, p14ARF, PD-L1, MET, LC3B, IGFBP7 and LGR5, associated to each hallmark of cancer.

Histological assessment & use of immunohistochemical markers for detection of dysplasia in Barrett's esophageal mucosa

BACKGROUND

Histological assessment of dysplasia in Barrett's esophagus (BE) has high inter-observer variability. Hence, use of ancillary markers for early detection of dysplasia in BE is an important clinical question.

METHODS

In this retrospective study consecutive cases of BE (n = 59), over a period of 4 years were included. Hematoxylin and eosin stained sections were reviewed independently by 3 senior qualified pathologists, who graded the dysplasia according to the Vienna Classification system and inter-observer agreement was analysed using the Kappa statistics. Subsequently Alpha-Methyl Acyl-CoA Racemase (AMACR), p53, CyclinD1, β-catenin, H2AX and M30 immunohistochemical (IHC) stains were examined on the following disease categories: BE with no dysplasia [NFD] (45), BE with indefinite for dysplasia (IFD) (4), low grade dysplasia (LGD) (3), high grade dysplasia (HGD) (2) and in adenocarcinomas (5). H score was calculated by adding up products of different grades of stain distribution and stain intensities (range of scores 0-300).

RESULTS

Among the 3 pathologists, overall agreement was poor (k 0.06; 95% CI -0.089 to 0.145), with highest disagreement noted for differentiating the LGD and IFDs (k = 0.21). After revising the histological criteria, the kappa improved to 0.53. Among the IHC stains performed, p53, β-catenin, H2AX and M30 stains were significantly useful to differentiate between IFD and LGD (P values: 0.04, 0.004, 0.05 & 0.04, respectively). AMACR and β-catenin stains though were up-regulated in HGD/adenocarcinomas than in other categories, their expression were not statistically different between the IFD and LGDs.

CONCLUSIONS

A detail histological scoring system may bring uniformity in histological interpretation of dysplasia in BE. Using a combined panel of IHC stains seems helpful in detection of dysplasia in BE, especially to differentiate the IFD and LGD changes in BE.

hERG1 behaves as biomarker of progression to adenocarcinoma in Barrett's esophagus and can be exploited for a novel endoscopic surveillance

Barrett's esophagus (BE) is the only well-known precursor lesion of esophageal adenocarcinoma (EA). The exact estimates of the annual progression rate from BE to EA vary from 0.07% to 3.6%. The identification of BE patients at higher risk to progress to EA is hence mandatory, although difficult to accomplish. In search of novel BE biomarkers we analyzed the efficacy of hERG1 potassium channels in predicting BE progression to EA. Once tested by immunohistochemistry (IHC) on bioptic samples, hERG1 was expressed in BE, and its expression levels increased during progression from BE to esophageal dysplasia (ED) and EA. hERG1 was also over-expressed in the metaplastic cells arising in BE lesions obtained in different BE mouse models, induced either surgically or chemically. Furthermore, transgenic mice which over express hERG1 in the whole gastrointestinal tract, developed BE lesions after an esophago-jejunal anastomosis more frequently, compared to controls. A case-control study was performed on 104 bioptic samples from newly diagnosed BE patients further followed up for at least 10 years. It emerged a statistically significant association between hERG1 expression status and risk of progression to EA. Finally, a novel fluorophore- conjugated recombinant single chain variable fragment antibody (scFv-hERG1-Alexa488) was tested on freshly collected live BE biopsies: it could recognize hERG1 positive samples, perfectly matching IHC data.Overall, hERG1 can be considered a novel BE biomarker to be exploited for a novel endoscopic surveillance protocol, either in biopsies or through endoscopy, to identify those BE patients with higher risk to progress to EA.

Cyclin D1 expression predicts postoperative distant metastasis and survival in resectable esophageal squamous cell carcinoma

Purpose

We aim to identify esophageal squamous cell carcinoma patients with increased risk of postoperative metastases.

Results

A high level of cyclin D1 expression, together with poor tumor cell differentiation and advanced tumor stages, increased risk of postoperative metastasis and decreased distant metastasis-free survival in ESCC in both cohorts. A high level of cyclin D1 expression also decreased overall survival in the training cohort (p < 0.01) but not in the validation cohort (p = 0.415). However, when the two cohorts of patients were pooled to obtain a larger case number, a high level of cyclin D1 expression was again demonstrated as an independent predictor that decreased overall survival (p < 0.01).

Methods

We used data from two institutions to establish training (n = 319) and validation (n = 164) cohorts. Tissue microarrays were generated for immunohistochemical evaluation. The correlation among cyclin D1 expression, clinicopathologic variables, postoperative distant metastases, overall survival, and distant metastasis-free survival were analyzed. Multivariate analyses were used to test the independent factors impacting postoperative distant metastases and survival. The outcomes generated from the training cohort were then tested using the validation cohort and pooled dataset.

Conclusions

High level of cyclin D1 expression increased distant metastasis, decreased overall survival and distant metastasis-free survival in resectable ESCC. Using a combination of cyclin D1 expression, tumor cell differentiation grade, and tumor stages, identifying patients with increased risk of postoperative metastases becomes possible.

Prediction of survival in patients with oesophageal or junctional cancer receiving neoadjuvant chemoradiotherapy and surgery

Background

The value of conventional prognostic factors is unclear in the era of multimodal treatment for oesophageal cancer. This study aimed to quantify the impact of neoadjuvant chemoradiotherapy (nCRT) and surgery on well established prognostic factors, and to develop and validate a prognostic model.

Methods

Patients treated with nCRT plus surgery were included. Multivariable Cox modelling was used to identify prognostic factors for overall survival. A prediction model for individual survival was developed using stepwise backward selection. The model was internally validated leading to a nomogram for use in clinical practice.

Results

Some 626 patients who underwent nCRT plus surgery were included. In the multivariable model, only pretreatment cN category and ypN category were independent prognostic factors. The final prognostic model included cN, ypT and ypN categories, and had moderate discrimination (c-index at internal validation 0·63).

Conclusion

In patients with oesophageal or oesophagogastric cancer treated with nCRT plus surgery, overall survival can best be estimated using a prediction model based on cN, ypT and ypN categories. Predicted survival according to this model showed only moderate correlation with observed survival, emphasizing the need for new prognostic factors to improve survival prediction.

Biomarkers of Barrett's esophagus

Barrett’s esophagus is the strongest risk for esophageal adenocarcinoma (EAC). Metaplasia in patients with BE may progress to dysplasia and then invasive carcinoma. Well-defined diagnostic, progressive, predictive, and prognostic biomarkers are needed to identify the presence of the disease, estimate the risk of malignant transformation, and predict the therapeutic outcome and survival of EAC patients. There are many predictive and prognostic markers that lack substantial validation, and do not allow stratification of patients with gastroesophageal reflux disease in clinical practice for outcome and effectiveness of therapy. In this short review we summarize the current knowledge regarding possible biomarkers, focusing on the pathophysiologic mechanisms to improve prognostic and therapeutic approaches.

A systematic review and meta-analysis of somatic and germline DNA sequence biomarkers of esophageal cancer survival, therapy response and stage

Recent advances in next generation sequencing reinforce the potential for DNA sequence markers to guide esophageal cancer management. We report the first systematic review and meta-analysis, identifying 94 markers of outcome and 41 of stage. Overall, evidence was poor. Meta-analyses demonstrated outcome associations for 6 tumor and 9 germline variants: priorities for prospective evaluation.

Introduction

There is an urgent need for biomarkers to help predict prognosis and guide management of esophageal cancer. This review identifies, evaluates and meta-analyses the evidence for reported somatic and germline DNA sequence biomarkers of outcome and stage.

Methods

A systematic review was carried out of the PubMed, EMBASE and Cochrane databases (20 August 2014), in conjunction with the ASCO Level of Evidence scale for biomarker research. Meta-analyses were carried out for all reported markers associated with outcome measures by more than one study.

Results

Four thousand and four articles were identified, 762 retrieved and 182 studies included. There were 65 reported markers of survival or recurrence 12 (18.5%) were excluded due to multiple comparisons. Following meta-analysis, significant associations were seen for six tumor variants (mutant TP53 and PIK3CA, copy number gain of ERBB2/HER2, CCND1 and FGF3, and chromosomal instability/ploidy) and seven germline polymorphisms: ERCC1 rs3212986, ERCC2 rs1799793, TP53 rs1042522, MDM2 rs2279744, TYMS rs34743033, ABCB1 rs1045642 and MTHFR rs1801133. Twelve germline markers of treatment complications were reported; 10 were excluded. Two tumor and 15 germline markers (11 excluded) of chemo (radio)therapy response were reported. Following meta-analysis, associations were demonstrated for mutant TP53, ERCC1 rs11615 and XRCC1 rs25487. There were 41 tumor/germline reported markers of stage; 27 (65.9%) were excluded.

Conclusions

Numerous DNA markers of outcome and stage have been reported, yet few are backed by high-quality evidence. Despite this, a small number of variants appear reliable. These merit evaluation in prospective trials, within the context of high-throughput sequencing and gene expression.

Genomic alterations in advanced esophageal cancer may lead to subtype-specific therapies

The development of targeted agents for metastatic esophageal or gastroesophageal junction (GEJ) tumors has been limited when compared with that for other common tumors. To date, the anti-human epidermal growth factor receptor-2 (HER-2) antibody, trastuzumab, in combination with chemotherapy, is the only approved novel agent for these cancers, and its use is limited to the small population of patients whose tumors overexpress HER-2. Despite recent progress in the field, median overall survival remains only 8-12 months for patients with stage IV esophageal or GEJ cancer. In this article, we examine the molecular aberrations thought to drive the development and spread of esophageal cancer and identify promising targets for specific tumor inhibition. Data from clinical studies of targeted agents are reviewed, including epidermal growth factor receptor antibodies, tyrosine kinase inhibitors, HER-2, and vascular endothelial growth factor-directed therapy. Current and future targets include MET, fibroblast growth factor receptor, and immune-based therapies. Evidence from trials to date suggests that molecularly unselected patient cohorts derive minimal benefit from most target-specific agents, suggesting that future collaborative investigation should focus on preselected molecular subgroups of patients with this challenging heterogeneous disease.

Signaling pathways in the molecular pathogenesis of adenocarcinomas of the esophagus and gastroesophageal junction

Esophageal adenocarcinoma develops in response to severe gastroesophageal reflux disease through the precursor lesion Barrett esophagus, in which the normal squamous epithelium is replaced by a columnar lining. The incidence of esophageal adenocarcinoma in the United States has increased by over 600% in the past 40 years and the overall survival rate remains less than 20% in the community. This review highlights some of the signaling pathways for which there is some evidence of a role in the development of esophageal adenocarcinoma. An increasingly detailed understanding of the biology of this cancer has emerged recently, revealing that in addition to the well-recognized alterations in single genes such as p53, p16, APC, and telomerase, there are interactions between the components of the reflux fluid, the homeobox gene Cdx2, and the Wnt, Notch, and Hedgehog signaling pathways.

GERD-Barrett-Adenocarcinoma: Do We Have Suitable Prognostic and Predictive Molecular Markers?

Due to unfavorable lifestyle habits (unhealthy diet and tobacco abuse) the incidence of gastroesophageal reflux disease (GERD) in western countries is increasing. The GERD-Barrett-Adenocarcinoma sequence currently lacks well-defined diagnostic, progressive, predictive, and prognostic biomarkers (i) providing an appropriate screening method identifying the presence of the disease, (ii) estimating the risk of evolving cancer, that is, the progression from Barrett's esophagus (BE) to esophageal adenocarcinoma (EAC), (iii) predicting the response to therapy, and (iv) indicating an overall survival—prognosis for EAC patients. Based on histomorphological findings, detailed screening and therapeutic guidelines have been elaborated, although epidemiological studies could not support the postulated increasing progression rates of GERD to BE and EAC. Additionally, proposed predictive and prognostic markers are rather heterogeneous by nature, lack substantial proofs, and currently do not allow stratification of GERD patients for progression, outcome, and therapeutic effectiveness in clinical practice. The aim of this paper is to discuss the current knowledge regarding the GERD-BE-EAC sequence mainly focusing on the disputable and ambiguous status of proposed biomarkers to identify promising and reliable markers in order to provide more detailed insights into pathophysiological mechanisms and thus to improve prognostic and predictive therapeutic approaches.

Prognostic significance of cyclin D1 polymorphisms on prostate-specific antigen recurrence after radical prostatectomy

BACKGROUND

Cyclin D1 (CCND1) is an important cell-cycle regulator involved in carcinogenesis and progression of prostate cancer. We tested whether genetic variations within the CCND1 gene are related to clinical outcomes in prostate cancer patients receiving radical prostatectomy.

METHODS

A total of 320 clinical localized prostate cancer patients who underwent radical prostatectomy in Taiwan were prospectively follow-up in this study. A total of 5 tagged single-nucleotide polymorphisms that captured the genetic variability across the CCND1 gene were genotyped, and the prognostic significance on prostate-specific antigen (PSA) recurrence was assessed using the Kaplan-Meier analysis and Cox regression model.

RESULTS

We found a polymorphism, rs9344, and 2 haplotypes, GAGG and CTGG, consisting of rs667515, rs2450254, rs9344, and rs678653, were associated with PSA recurrence (P ≤ 0.033). After adjusting for other clinicopathologic predictors, including age, PSA levels, pathologic stage, Gleason score, and surgical margin, rs9344 and the haplotype CTGG remained significant (P ≤ 0.044). The model based on clinical variables plus CCND1 rs9344 or haplotype showed improvement over the model without genetic information, as indicated by ≥ 7.2 % net reclassification improvement (P ≤ 0.040), integrated discrimination index (P ≤ 0.041), and likelihood ratio test (P ≤ 0.028).

CONCLUSION

Our data suggest that the CCND1 rs9344 and a specific haplotype CTGG may be prognostic factors for PSA recurrence after radical prostatectomy.

Cyclin D1 G870A polymorphism is a risk factor for esophageal cancer among Asians

Investigations concerning the association of Cyclin D1 (CCND1) G870A polymorphism with esophageal cancer risk have generated conflicting results. Thus, meta-analyses were conducted. The overall data suggest that CCND1 G870A variation might have an association with increased esophageal cancer susceptibility. In subgroup analyses on ethnicity, homozygous AA alleles might elevate esophageal cancer risk among Asians but not Caucasians. In subgroup analysis on histological types, no association was found in either the adenocarcinoma or the squamous cell carcinoma subgroup. Collectively, results suggest that CCND1 G870A polymorphism might be a low-penetrant risk factor for esophageal carcinoma, particularly among Asians.

Surveillance for gastrointestinal malignancies

Gastrointestinal (GI) malignancies are notorious for frequently progressing to advanced stages even in the absence of serious symptoms, thus leading to delayed diagnoses and dismal prognoses. Secondary prevention of GI malignancies through early detection and treatment of cancer-precursor/premalignant lesions, therefore, is recognized as an effective cancer prevention strategy. In order to efficiently detect these lesions, systemic application of screening tests (surveillance) is needed. However, most of the currently used non-invasive screening tests for GI malignancies (for example, serum markers such as alpha-fetoprotein for hepatocellular carcinoma, and fecal occult blood test, for colon cancer) are only modestly effective necessitating the use of highly invasive endoscopy-based procedures, such as esophagogastroduodenoscopy and colonoscopy for screening purposes. Even for hepatocellular carcinoma where non-invasive imaging (ultrasonography) has become a standard screening tool, the need for repeated liver biopsies of suspicious liver nodules for histopathological confirmation can’t be avoided. The invasive nature and high-cost associated with these screening tools hinders implementation of GI cancer screening programs. Moreover, only a small fraction of general population is truly predisposed to developing GI malignancies, and indeed needs surveillance. To spare the average-risk individuals from superfluous invasive procedures and achieve an economically viable model of cancer prevention, it’s important to identify cohorts in general population that are at substantially high risk of developing GI malignancies (risk-stratification), and select suitable screening tests for surveillance in these cohorts. We herein provide a brief overview of such high-risk cohorts for different GI malignancies, and the screening strategies that have commonly been employed for surveillance purpose in them.

Rapid downregulation of cyclin D1 induced by geranylgeranoic acid in human hepatoma cells

Geranylgeranoic acid (GGA) and its derivatives are currently under development as chemopreventive agents against second primary hepatoma in Japan. We aimed to evaluate chemoprevention targets of GGA and a surrogate marker of chemopreventive response to clarify the molecular mechanism of hepatoma chemoprevention with GGA. Human hepatoma-derived cell lines such as HuH-7, PLC/PRF/5, and HepG-2, were treated with GGA and its derivatives. Cellular dynamics of several cell-cycle-related proteins were assessed by either immunoblotting or immunofluorescence method. The cellular expression of cyclin D1 protein was suppressed immediately after GGA treatment. This reduction was partially blocked by pretreatment with 26S proteasome inhibitor MG-132, indicating that proteasomal degradation was involved in GGA-induced disappearance of cyclin D1. A phosphorylation of retinoblastoma protein (RB) at serine 780, a target site of cyclin D1-dependent kinase 4, was rapidly decreased in GGA-treated HuH-7 cells. Furthermore, subcellular fractionation, Western blotting, and immunofluorescence revealed GGA-induced nuclear accumulation of RB. These results strongly suggest that cyclin D1 may be a target of chemopreventive GGA in human hepatoma cells. GGA-induced rapid repression of cyclin D1, and a consequent dephosphorylation and nuclear translocation of RB, may influence cell cycle progression and may be relevant to GGA-induced cell death mechanisms.

CIP2A is overexpressed in esophageal squamous cell carcinoma

A human oncoprotein-designed cancerous inhibitor of PP2A (CIP2A) has been recently identified, which can stabilize c-Myc protein by inhibiting its degradation mediated by protein phosphatase 2A (PP2A) in tumor cells and promote the proliferation of various cancer cells. Esophageal squamous cell carcinoma (ESCC) is a highly aggressive cancer with poor prognosis worldwide. However, the underlying molecular mechanism of the development of ESCC is still poorly understood. In the present study, the CIP2A expression between normal and malignant esophageal tissues was compared by immunohistochemical analysis; moreover, the mechanisms of CIP2A-mediated tumorigenesis were investigated by evaluating its role in cell proliferation, cell cycle, apoptosis and senescence. We found that the positive staining of CIP2A was found in 36 of 40 (90%) of cancer tissues, whereas only 8 of 40 (20%) normal esophageal mucosa exhibited positive CIP2A staining. The CIP2A is significantly overexpressed in human esophageal tumors when compared with normal tissues (χ(2) = 39.6, P < 0.01). On the other hand, the CIP2A expression was not associated with age, gender, tumor burden, or differentiation status. Depletion of CIP2A expression led to impaired clonogenicity and senescence, which is the primary mechanism of CIP2A in oncogenesis. Therefore, CIP2A may be a candidate in diagnosis and therapy of esophageal cancer.

Biomarkers in Barrett’s esophagus and esophageal adenocarcinoma: Predictors of progression and prognosis

Barrett’s esophagus is a well-known premalignant lesion of the lower esophagus that is characterized by intestinal metaplasia of the squamous epithelium. It is clinically important due to the increased risk (0.5% per annum) of progression to esophageal adenocarcinoma (EA), which has a poor outcome unless diagnosed early. The current clinical management of Barrett’s esophagus is hampered by the lack of accurate predictors of progression. In addition, when patients develop EA, the current staging modalities are limited in stratifying patients into different prognostic groups in order to guide the optimal therapy for an individual patient. Biomarkers have the potential to improve radically the clinical management of patients with Barrett’s esophagus and EA but have not yet entered mainstream clinical practice. This is in contrast to other cancers like breast and prostate for which biomarkers are utilized routinely to inform clinical decisions. This review aims to highlight the most promising predictive and prognostic biomarkers in Barrett’s esophagus and EA and to discuss what is required to move the field forward towards clinical application.

Gastroesophageal Reflux Disease and Helicobacter pylori: What May Be the Relationship?

Relationship between Helicobacter pylori (H. pylori) and gastroesophageal reflux disease (GERD) is controversial. We aimed to review the possible relationship between H. pylori infection and GERD. Epidemiological data indicate an inverse relationship between frequency of H. pylori infection and prevalence of GERD and its complications like Barrett's esophagus and esophageal adenocarcinoma. H. pylori eradication in patients with peptic ulcer disease may be associated with increased risk of development of GERD compared with untreated patients. Infection with cagA bearing strains of H. pylori was associated with less severe GERD including endoscopic esophagitis, possibly due to pangastritis leading to hypochlorhydria. Recent studies on inflammatory markers (IL-1β and IL-1RN) suggest pro-inflammatory genotypes to be protective against development of severe GERD, especially in patients with H. pylori infection. Identification of candidate genes playing an important role in gastric acid secretion and visceral hypersensitivity to the esophageal epithelium might help in early detection of individuals susceptible to develop GERD. Interplay between H. pylori and host factors play an important role in the pathogenesis of GERD.

Barrett esophagus: an update

Many developments have been made in the field of Barrett esophagus that have tremendous clinical implications. There are new definitions of Barrett esophagus that have had an immediate clinical impact on cancer risk and screening. Of interest is the definition by the British Society of Gastroenterology, which does not require the presence of intestinal metaplasia for a diagnosis of Barrett esophagus. Imaging techniques that allow improved visualization of intestinal metaplasia at the cellular level are now being used in clinical practice. New hypotheses elucidating the progression from squamous epithelium to intestinal metaplasia have been proposed. Indeed, the crucial role that transcription factors have in the pathogenesis of Barrett esophagus has been clarified. Improved characterization of the molecular mechanisms underlying Barrett esophagus is an incentive to undertake more basic science research in this field. Such research could also help with the development of chemoprevention strategies for this precancerous condition. This Review discusses the advances in understanding of the pathogenesis, diagnosis and treatment of Barrett esophagus.

Genetic predisposition to gastro-oesophageal cancer

Gastro-oesophageal cancers were ranked as the second cause of death from cancer worldwide despite a steady decrease in incidence for squamous cell carcinoma (SCC) of the oesophagus and distal gastric cancers. Adenocarcinoma of the oesophagus (OAC) is the tumour whose incidence has seen the highest increase in the past 30 years. Most of these cancers are strongly associated with environmental and life style risk factors such as smoking and alcohol for SCC, gastro-oesophageal reflux for OAC and Helicobacter pylori for distal gastric cancer. It may therefore be unsurprising that SCC is associated with polymorphisms in ALDH2 and ADH1B1, enzyme involved in alcohol metabolism, and with CYP1A1, involved in xenobiotics detoxification. OAC, whose incidence in absolute terms remains low, has been much less studied and at best the associations identified with risk are weak. Diffuse type gastric cancers while relatively uncommon have a strong genetic association with mutation of the CDH1 gene and prostate specific cancer antigen (PSCA) was demonstrated in a GWAS to be associated with an increased risk of diffuse gastric cancer but not intestinal type gastric cancer. This family of cancer is more associated with polymorphisms at the IL-1beta, IL-1RN loci and MHTFR loci. Specific strains of H pylori containing the virulence factors VacA s1, VacA m1 and cag A together with polymorphism at the IL-1beta and IL-1RN loci have up to a 87-fold increase in risk for developing intestinal type gastric cancer. While progress has been made to identify genetic variants associated with upper-gastrointestinal cancers, the relative small prevalence for some subtypes underlies the need for consortia, especially in view of the large variations in the prevalence of polymorphisms between different populations.

p53 Arg72Pro, MDM2 T309G and CCND1 G870A polymorphisms are not associated with susceptibility to esophageal adenocarcinoma

p53 Arg72Pro, MDM2 T309G, and CCND1 G870A are functional single-nucleotide polymorphisms (SNPs) in key genes that regulate apoptosis and cell cycle. Variant genotypes of these SNPs have been associated with increased risk and earlier age of onset in some cancers. We investigated the association of these SNPs with susceptibility to esophageal adenocarcinoma in a large, North American case-control study. Three hundred and twelve cases and 454 cancer-free controls recruited in Boston, USA were genotyped for each of the three SNPs, and demographic and clinical data were collected. Genotype frequencies for each of the three SNPs did not deviate from the Hardy-Weinberg equilibrium, and did not differ between cases and controls. Odds ratios (OR), adjusted for clinical risk factors, for the homozygous variant genotypes were 0.99 (95% confidence interval [CI] 0.57-1.72) for p53 Pro/Pro, 0.81 (95% CI 0.52-1.28) for MDM2 G/G, and 0.97 (95% CI 0.64-1.49) for CCND1 A/A. The analysis was adequately powered (80%) to detect ORs of 1.37, 1.35, and 1.34 for each SNP, respectively. In contrast to the results of smaller published studies, no association between p53 Arg72Pro, MDM2 T309G, and CCND1 G870A SNPs and susceptibility to esophageal adenocarcinoma, age of onset, or stage of disease at diagnosis was detected.

CyclinD1 and interleukin-1 receptor antagonist polymorphisms are associated with prognosis in neoadjuvant-treated gastric carcinoma

PURPOSE

We evaluated DNA polymorphisms in genes related to DNA repair, cell-cycle control and tumour microenvironment to determine possible associations with response and survival in neoadjuvant-treated gastric cancer patients.

PATIENTS AND METHODS

One hundred and seventy eight patients who received platinum/5FU-based chemotherapy were genotyped for 10 polymorphisms in nine genes (ERCC1: Asn118Asn, C > T; ERCC1: 8092C > A; TP53: Arg72Pro, G < C; cyclinD1: Pro241Pro, G > A; STK15: Phe31Ile, A > T; VEGF: 936C > T; TNF-alpha: -308G > A; interleukin-1b (IL-1B): -511C >T; IL-1 receptor antagonist (IL-1RN): variable tandem repeat; IL-8: -251T>A). Genotypes were correlated with histopathological and clinical response and overall (OS) and progression-free survival (PFS).

RESULTS

Only the cyclinD1 genotypes were associated with clinical response (P(x)(2)=0.044). Significantly worse survival rates were noted in patients homozygous for the G-allele as compared to patients with the AG or AA genotypes of the cyclinD1 polymorphism (OS: P(log-rank) = 0.024; PFS: P(log-rank)=0.007) and in patients homozygous for the short allele compared to all other genotypes at the IL-1RN polymorphic locus (OS: P(log-rank) = 0.026; PFS: P(log-rank) = 0.013). The combination of both unfavourable genotypes demonstrated strong prognostic relevance (OS: P(log-rank) = 0.006; PFS: P(log-rank) = 0.001). Multivariate analysis for OS in the group of completely resected patients (n = 139) revealed statistical significance for ypM (P < 0.001), histopathological response (P < 0.001) and the combined cyclinD1/IL-1RN genotypes (P = 0.043).

CONCLUSION

The cyclinD1 and IL-1RN polymorphisms were associated with survival. The combination of specific cyclinD1 and IL-1RN genotypes showed a particular prognostic relevance and should be considered an independent prognostic marker for neoadjuvant-treated gastric cancer patients.

Clinical puzzle: Barrett's oesophagus

The incidence of oesophageal adenocarcinoma has increased dramatically in the Western world over the past two decades. Owing to its dismal 5-year prognosis in advanced stages, early diagnosis is required in order to improve survival rates. Barrett's oesophagus (Barrett's) has been recognised as a pre-cancerous condition generally associated with chronic and severe gastro-oesophageal reflux disease (GORD). Barrett's is defined as the substitution of the normal stratified squamous epithelium of the oesophagus with a columnar cell lining with intestinal-type differentiation; a phenomenon commonly referred to as intestinal metaplasia. Clinical challenges include finding cost-effective ways to identify patients with Barrett's, stratifying them according to their cancer risk and improving the diagnostic potential of endoscopic sampling. Research has generally focused on identifying tissue biomarkers to predict cancer risk in these patients. The oesophagus is easily accessible, making it possible to work with human samples, but most studies have been retrospective and underpowered. Endoscopic surveillance programmes are problematic due to sampling bias and the subjective grading of dysplasia. The lack of an animal model has hampered studies to elucidate markers of the transition from Barrett's to cancer and to test potential therapeutics. However, a number of in vitro model systems are ripe for further development into more physiologically complete systems.

Cyclin D1 and cancer development in laryngeal premalignancy patients

In a previous trial, we found that combined 13-cis-retinoic acid, IFN-alpha, and alpha-tocopherol more effectively reversed advanced premalignant lesions of the larynx than of the oral cavity and that cyclin D1 (CD1) G/A870 single nucleotide polymorphism correlated with cancer risk. We conducted the present trial primarily to confirm the clinical activity of the combination in advanced laryngeal premalignancy and to confirm and extend our findings on CD1, both genotype and protein expression, in association with cancer risk in this setting. Twenty-seven moderate-to-severe laryngeal dysplasia patients underwent induction with combined 13-cis-retinoic acid daily, alpha-IFN twice weekly, and alpha-tocopherol daily for 1 year; 14 nonprogressing patients then were randomized to maintenance fenretinide or placebo for 2 years. During induction, two patients had pathologic complete responses, six had partial responses (30% overall response rate), and five developed laryngeal cancer. There were no significant differences between maintenance fenretinide and placebo in response or cancer rates. Ten patients developed cancer overall. Twenty-four patients were evaluated for the CD1 G/A870 genotype, and 23 for pretreatment and posttreatment CD1 protein expression. Consistent with our earlier report, shorter cancer-free survival was associated with the CD1 AA/AG genotype (P = 0.05). Extending our earlier work, high CD1 expression was associated with worse cancer-free survival overall (P = 0.04) and within each CD1 genotype group. These findings support CD1 genotype and protein expression as important risk markers for laryngeal cancer and suggest future trials targeting upstream regulators of CD1 transcription.

Association between CCND1 G/A870 polymorphism, allele-specific amplification, cyclin D1 expression, and survival in esophageal and lung carcinoma

PURPOSE

Cyclin D1 is found on 11q13, which is a region frequently amplified in several tumor types. The CCND1 locus gives rise to at least two protein isoforms of D1 (D1a and D1b). A common G/A polymorphism (G/A870) is thought to influence the expression levels of D1a and D1b. D1b has been suggested to be increased in the presence of the A allele and more oncogenic than D1a. Furthermore, the A allele has been reported to correlate with increased risk of carcinoma in several tumor types, suggesting that this polymorphism and D1b are important in tumor progression. However, contradictory data about the polymorphism, D1 variant expression, and correlation with survival have been reported. We explored the relationship between gene amplification, G/A870 genotype, D1a and D1b expression, and overall survival in esophageal adenocarcinoma and non-small cell lung cancer.

EXPERIMENTAL DESIGN

DNA and RNA were isolated from 54 esophageal adenocarcinoma samples and 89 non-small cell lung cancer samples and were analyzed for gene amplification, genotype at the polymorphism, gene expression, and association with overall survival.

RESULTS

The D1 variant expression did not correlate with amplification, genotype, or overall survival in either tumor type. The total D1 expression correlated with decreased patient survival. Several other genes on 11q13 also seem to be overexpressed and correlated with decreased survival.

CONCLUSIONS

We report that the G/A870 polymorphism does not correlate with patient survival, or with D1a or D1b expression. However, the total D1 expression and the expression of several other genes on 11q13 seem to be associated with esophageal adenocarcinoma patient survival.

Polymorphism Arg290Arg in esophageal-cancer-related gene 1 (ECRG1) is a prognostic factor for survival in esophageal cancer

BACKGROUND

Esophageal cancer is one of the most frequent cancers worldwide and is associated with poor outcome. Besides clinicopathological data, few prognostic molecular markers exist. Esophageal-cancer-related gene1 (ECRG1) short tandem repeats are associated with higher risk for developing esophageal squamous cell carcinoma. The aim of the present study was to evaluate the impact of DNA polymorphisms in the coding region of ECRG1 in esophageal carcinoma.

METHODS

Genomic DNA of 107 patients with esophageal cancer that underwent complete surgical resection between 1997 and 2005 was extracted. DNA was analyzed for ECRG1 polymorphisms Arg290Arg, Arg290Gln, and Gln290Gln by PCR and gel electrophoresis. Polymorphisms were correlated with survival data by the Kaplan-Meier method, multivariate Cox regression analysis, and odds ratio were determined. For all variables, cross tables were generated, followed by calculation of the p value by using the chi-square test/Fisher-exact test.

RESULTS

Follow-up data of 102 patients with esophageal cancer were available after complete surgical resection for a median follow-up time of 24.3 months. Polymorphism Arg290Arg was found in 47 patients (46.1%), Arg290Gln in 48 patients (47.0%), and Gln290Gln in seven cases (6.9%). Arg290Arg polymorphism was significantly associated with reduced overall survival (p = 0.01) and tumor-free survival (p = 0.01) by the log-rank test. Multivariate regression analysis by Cox revealed polymorphism Arg290Arg to be a significant prognostic factor for survival (p = 0.012).

CONCLUSIONS

Polymorphism Arg290Arg in ECRG1 is associated with poor clinical outcome after complete surgical resection in patients with esophageal cancer.

Correlations between selected tumor markers and fluorodeoxyglucose maximal standardized uptake values in esophageal cancer

OBJECTIVE

Esophageal cancer tumor biology is best assessed clinically by 2-[18F]fluoro-2-deoxy-d-glucose (FDG)-PET. Both FDG-PET maximal positron emission tomography (PET) standardized uptake values (SUVmax) and selected tumor markers have been shown to correlate with stage, nodal disease, and survival in esophageal cancer. Interestingly, there is limited data examining the relationship between FDG-PET SUVmax and expression of these tumor markers in esophageal cancer. The purpose of this study was to determine the correlation of tumor markers with FDG-PET SUVmax in esophageal cancer.

METHODS

FDG-PET SUVmax was calculated in 67 patients with esophageal cancer of which 59 (88%) had adenocarcinoma. Neoadjuvant radiotherapy and/or chemotherapy were administered to 42% (28/67) of patients. Esophageal tumor tissue and surrounding normal tissue was obtained and tissue microarrays were created. Immunohistochemical analysis was performed for five known esophageal cancer tumor markers (GLUT-1, p53, cyclin D1, epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF)). Assessment of each tumor marker was made by two independent, blinded pathologists using common grading criteria of intensity and percentage of cells stained. A p value <0.05 was considered significant.

RESULTS

There were 55 men (82%) and 12 women (18%) with a median age of 63 years (range 40-83). Pathologic staging included stage I (n=29, 43%), stage II (n=19, 28%), stage III disease (n=18, 27%), and stage IV disease (n=1, 2%). PET SUVmax correlated with T stage (p=0.001). In patients undergoing surgery without induction therapy, increasing SUVmax values correlated with increased expression of GLUT-1 transporter (p=0.01). There was no correlation between SUVmax and EGFR, cyclin D1, VEGF, or p53 expression in primary tumor.

CONCLUSIONS

FDG-PET SUVmax correlates with an increased expression of GLUT-1 transporter in esophageal cancer specimens not subjected to induction therapy. No significant difference in tumor marker expression was noted between patients undergoing induction therapy or surgery alone except p53 expression decreased in primary tumors following induction therapy. Failure of SUVmax values to correlate with known prognostic esophageal cancer tumor markers suggests that FDG-PET may have limited clinical utility in assessing response to therapies targeting these markers.

Sorafenib inhibits MAPK-mediated proliferation in a Barrett's esophageal adenocarcinoma cell line

Esophageal adenocarcinoma continues to rise in incidence. Despite recognition of Barrett's metaplasia as the histological precursor, prognosis remains poor. The mitogen-activated protein kinases (MAPK) pathway is activated in Barrett's-associated dysplasia and adenocarcinoma and this activation is, in part, due to acid and bile acid reflux. We investigated the effects of sorafenib, an orally active Raf-inhibitor, on acid and bile acid-stimulated growth and signaling in SEG-1 cells, derived from a Barrett's esophageal cancer. SEG-1 cells were pretreated with sorafenib or vehicle and subsequently stimulated with acid or bile acid. MAPK signals, including phospho-ERK and phospho-p38, as well as cyclin D1 expression were assessed by Western blotting. Cell proliferation was measured by WST-1 colorimetric assay. Acid (pH 3.0-4.0) and bile acid (taurocholate 50-100 micromol/L) activated ERK and p38. Acid and bile acid exposure also increased levels of cyclin D1, a G1 to S cell cycle regulator. Furthermore, acid and taurocholate exposure increased cell proliferation. Sorafenib abrogated MAPK activation and cyclin D1 up-regulation and significantly inhibited cell growth. In summary, sorafenib inhibits acid or bile acid-stimulated Barrett's esophageal cancer cell proliferation by a mechanism involving the MAPK pathway. Our results suggest that sorafenib might be useful in the management of Barrett's-associated dysplasia and adenocarcinoma. These findings provide a foundation for in vivo studies to assess the efficacy of sorafenib in Barrett's-related neoplasia.

Genetic polymorphisms and head and neck cancer outcomes: a review

Head and neck cancer (HNC) patients have variable prognoses even within the same clinical stage and while receiving similar treatments. The number of studies of genetic polymorphisms as prognostic factors of HNC outcomes is growing. Candidate polymorphisms have been evaluated in DNA repair, cell cycle, xenobiotic metabolism, and growth factor pathways. Polymorphisms of XRCC1, FGFR, and CCND1 have been consistently associated with HNC survival in at least two studies, whereas most of the other polymorphisms have either conflicting data or were from single studies. Heterogeneity and lack of description of patient populations and lack of accounting for multiple comparisons were common problems in a significant proportion of studies. Despite a large number of exploratory studies, large replication studies in well-characterized HNC populations are warranted.

A functional epidermal growth factor (EGF) polymorphism, EGF serum levels, and esophageal adenocarcinoma risk and outcome

PURPOSE

The epidermal growth factor (EGF) pathway is important in esophageal adenocarcinoma (EAC) tumorigenesis. We hypothesized that the EGF A61G homozygous variant genotype (GG) is (a) both a risk and poor prognostic factor for EAC and (b) associated with higher EGF serum levels in individuals with gastroesophageal reflux disease (GERD).

EXPERIMENTAL DESIGN

Using unconditional logistic regression, we compared EGF A61G in 312 EAC cases and 447 GERD-free controls, adjusting for age, gender, smoking history, and healthy adult body mass index. Using the method of Kaplan and Meier, log-rank tests, and Cox proportional hazard models, we correlated EGF A61G with overall and failure-free survival in the EAC cases. Serum EGF levels and EGF genotype (G/G versus others) were correlated in 144 GERD patients using Wilcoxon rank sum tests.

RESULTS

The EGF A61G G/G genotype conferred increased EAC risk, with an adjusted odds ratio of 1.81 (95% confidence interval, 1.2-2.7), and was even higher in the subgroup of EAC patients with concurrent Barrett's esophagus (adjusted odds ratio, 2.18; 95% confidence interval, 1.3-3.7). However, EGF A61G was not associated with a more aggressive phenotype or prognosis in EAC patients. Higher serum EGF levels were found in GERD patients carrying G/G compared with A/A or A/G (P = 0.03, Wilcoxon rank sum test).

CONCLUSION

The EGF A61G G/G genotype is associated with a near 2-fold greater risk of EAC. The G/G allele was also associated with higher EGF levels in tumor-free patients with GERD. EGF genotyping can potentially identify high-risk patients with GERD and Barrett's metaplasia who might benefit from increased surveillance.

Value of endoscopic ultrasound staging in conjunction with the evaluation of lymphovascular invasion in identifying low-risk esophageal carcinoma

BACKGROUND

With increasing emphasis on endoscopic therapy (ET) for T1 esophageal carcinoma, the identification of low-risk patients is critical. It was hypothesized that endoscopic ultrasonography (EUS) in concert with detailed histopathologic evaluation would identify low-risk cancers for an appropriate but organ-preserving strategy.

METHODS

All patients who had pretreatment EUS and underwent esophagectomy as primary therapy for esophageal cancer between 1999 and 2006 were analyzed retrospectively. The accuracy of EUS in predicting the correct pathologic stage was assessed along with a histopathologic reevaluation including lymphovascular invasion (LVI). Pathologic stage and various features were incorporated into a multivariate logistic regression model.

RESULTS

A total of consecutive 87 esophageal cancer patients (81 with adenocarcinoma) were evaluable for this analysis. EUS correctly diagnosed 59 T1 cancers and 20 T2-4 cancers but understaged cancers in 2 patients and overstaged cancers in 6 patients. EUS correctly identified 8 patients with lymph node metastases but not 13 other patients. The accuracy, sensitivity, and specificity of EUS for T1 cancers were 91%, 91%, and 91%, respectively; for T1a (intramucosal) cancers, the accuracy, sensitivity, and specificity were: 82%, 67%, and 93%, respectively, and for lymph node involvement these same values were 81%, 38%, and 94%, respectively. LVI was found to be an independent predictor of lymph node metastases on the multivariate analysis (P = .02).

CONCLUSIONS

Data from the current study demonstrate that EUS has excellent accuracy, sensitivity, and specificity (91% each) for identifying T1 esophageal cancers and LVI is an independent predictor of lymph node metastases. A strategy for preservation of the esophagus may be possible in patients who have EUS-designated T1 cancer without LVI after successful ET.

Genetics of gastroesophageal cancer: paradigms, paradoxes, and prognostic utility

Hereditary diffuse gastric cancer and tylosis are autosomal dominant cancer susceptibility syndromes. Accumulating evidence also suggests a genetic contribution to Barrett's esophagus and adenocarcinoma, traditionally considered acquired disorders. In this article we review the current knowledge on the genetic mechanisms underlying hereditary diffuse gastric cancer, tylosis, and Barrett's esophagus. Hereditary diffuse gastric cancer is a paradigm for hereditary cancer susceptibility syndromes with E-cadherin implicated as the dominant oncogene in up to one-third of cases. Tylosis in contrast remains the paradox as whilst the putative abnormality has been localized to the long arm of chromosome 17, sequencing of this region has failed to reveal a disease causing mutation. In the case of Barrett's esophagus and adenocarcinoma, although a validated specific disease-associated gene is yet to be identified, the increasing body of evidence of a possible genetic link is paving the way for subsequent prognostic studies such as AspECT (Aspirin Esomeprazole Chemoprevention Trial). For the clinician these advances in understanding are already having implications for practice in terms of improved screening and the stratification of management strategies. As the mechanisms continue to be defined, there is the real possibility that these mechanisms could be exploited or subverted in the design of new therapies. In the meantime, however, clinicians should undertake rigorous biopsy programs to ensure early invasive lesions are detected.

Pharmacogenetics of EGFR and VEGF inhibition

Even though treatment of several types of solid tumours has improved in the past few years with the introduction of the monoclonal antibodies against epidermal growth factor receptor (EGFR) and vascular endothelial growth factor (VEGF), response rates to these targeted therapies are modest. Pharmacogenetic factors have the potential to select patients with higher chance of response to agents that target these pathways. This review provides an overview over germ-line variations in genes that are potentially involved in the pharmacodynamics of the monoclonal antibodies cetuximab, panitumumab and bevacizumab, and which may underlie variable anti-tumour response.

Molecular mechanisms of liver carcinogenesis in the mdr2-knockout mice

Mouse models of hepatocellular carcinoma (HCC) simulate specific subgroups of human HCC. We investigated hepatocarcinogenesis in Mdr2-knockout (Mdr2-KO) mice, a model of inflammation-associated HCC, using gene expression profiling and immunohistochemical analyses. Gene expression profiling showed that although Mdr2-KO mice differ from other published murine HCC models, they share several important deregulated pathways and many coordinately differentially expressed genes with human HCC data sets. Analysis of genome positions of differentially expressed genes in liver tumors revealed a prolonged region of down-regulated genes on murine chromosome 8 in three of the six analyzed tumor samples. This region is syntenic to human chromosomal regions that are frequently deleted in human HCC and harbor multiple tumor suppressor genes. Real-time reverse transcription-PCR analysis of 16 tumor samples confirmed down-regulation of several tumor suppressors in most tumors. We show that in the aged Mdr2-KO mice, cyclin D1 nuclear level is increased in dysplastic hepatocytes that do not form nodules; however, it is decreased in most dysplastic nodules and in liver tumors. We found that this decrease is mostly at the protein, rather than the mRNA, level. These findings raise the question on the role of cyclin D1 at early stages of hepatocarcinogenesis in the Mdr2-KO HCC model. Furthermore, we show that most liver tumors in Mdr2-KO mice were characterized by the absence of beta-catenin activation. In conclusion, the Mdr2-KO mouse may serve as a model for beta-catenin-negative subgroup of human HCCs characterized by low nuclear cyclin D1 levels in tumor cells and by down-regulation of multiple tumor suppressor genes.