Oesophageal cancer and amplification of the human cyclin D gene CCND1/PRAD1

Discovery of Anticancer Activity of Amentoflavone on Esophageal Squamous Cell Carcinoma: Bioinformatics, Structure-Based Virtual Screening, and Biological Evaluation

Esophageal squamous cell carcinoma (ESCC) is the most common primary esophageal malignancy with poor prognosis. Here, due to the necessity for exploring potential therapies against ESCC, we obtained the gene expression data on ESCC from the TCGA and GEO databases. Venn diagram analysis was applied to identify common targets. The protein-protein interaction network was constructed by Cytoscape software, and the hub targets were extracted from the network via cytoHubba. The potential hub nodes as drug targets were found by pharmacophore-based virtual screening and molecular modeling, and the antitumor activity was evaluated through in vitro studies. A total of 364 differentially expressed genes (DEGs) in ESCC were identified. Pathway enrichment analyses suggested that most DEGs were mainly involved in the cell cycle. Three hub targets were retrieved, including CENPF, CCNA2 (cyclin A), and CCNB1 (cyclin B1), which were highly expressed in esophageal cancer and associated with prognosis. Moreover, amentoflavone, a promising drug candidate found by pharmacophore-based virtual screening, showed antiproliferative and proapoptotic effects and induced G1 in esophageal squamous carcinoma cells. Taken together, our findings suggested that amentoflavone could be a potential cell cycle inhibitor targeting cyclin B1, and is therefore expected to serve as a great therapeutic agent for treating esophageal squamous cell carcinoma.

Effects of Baneh (Pistacia atlantica) Gum on Human Breast Cancer Cell Line (MCF-7) and Its Interaction with Anticancer Drug Doxorubicin

Pistacia atlantica is one of the species of Anacardiaceae that grows in the wild in different regions of Iran. Traditionally, anacardiaceae family has antibacterial, fungicidal, and cytotoxic properties. Therefore, the present study was designed to investigate the possible cytotoxic and anti-proliferative properties of Baneh gum. Cytotoxicity of the plant gum was determined using MTT assay on MCF-7 human breast cancer cells. The cellular makers of apoptosis (caspase3 and P53) and cell proliferation (Cyclin-D1) were evaluated by western blotting. Doxorubicin was used as anticancer control drug in combination treatment. The result showed that Baneh gum (100 µg/mL) significantly induced cell damage, activated caspase3, and increased P53 protein level. In addition, Cyclin-D1 was significantly decreased in gum-incubated cells. Furthermore, combination treatment of cells with Baneh gum (25 µg/mL) and doxorubicin (200 nM) produced a significant cytotoxic effect as compared to each drug alone. In conclusion, Baneh gum (100 µg/mL) has a potential pro-apoptotic/anti-proliferative property against human breast cancer cells and its combination with doxorubicin in low doses may induce cell death effectively and be a potent modality to treat this type of cancer.

In silico dissection of miRNA targetome polymorphisms and their role in regulating miRNA-mediated gene expression in esophageal cancer

Esophageal cancer is the eighth most common cancer worldwide. Also middle-aged obese adults with higher body mass index during childhood have a greater risk to develop esophageal cancer. The contribution of microRNAs to esophageal cancer has been extensively studied and it became clear that these noncoding RNAs may play crucial roles in pathogenesis, diagnosis and prognosis of the disease. Increasing evidences have suggested that polymorphisms perturbing microRNA targetome (i.e., the compendium of all microRNA target sites) are associated with cancers including esophageal cancer. However, the extent to which such variants contribute to esophageal cancer is still unclear. In this study, we applied an in silico approach to systematically identify polymorphisms perturbing microRNA targetome in esophageal cancer and performed various analyses to predict the functional consequences of the occurrence of these variants. The computational results were integrated to provide a prioritized list of the most potentially disrupting esophageal cancer-implicated microRNA targetome polymorphisms along with the in silico insight into the mechanisms with which such variations may modulate microRNA-mediated regulation. The results of this study will be valuable for future functional experiments aimed at dissecting the roles of microRNA targetome polymorphisms in the onset and progression of esophageal cancer.

Insights into the potential use of microRNAs as a novel class of biomarkers in esophageal cancer

MicroRNAs (abbreviated miRNAs) have been demonstrated to be involved in tumorigenesis and cancer development and proposed as promising biomarkers in cancer diagnosis. Numerous studies have observed the aberrant expression of miRNAs in esophageal cancer. However, there are some discrepant results. Thus, we conducted this meta-analysis to identify the overall accuracy of miRNAs in the diagnosis of esophageal cancer. A comprehensive literature search was conducted in PubMed and other databases using combinations of key words. The summary receiver operator characteristic curves were plotted to assess the overall diagnostic performance of miRNAs. Chi-squared and I(2) tests were used to assess the heterogeneity between studies. Additionally, we conducted subgroup and sensitivity analyses to analyze the potential sources of heterogeneity. In total, 33 studies from 12 articles were available in this meta-analysis. The pooled sensitivity, specificity, positive and negative likelihood ratio (PLR, NLR) diagnostic odds ratio, and area under the curve were 0.80, 0.80, 4.0, 0.25, 16, and 0.87, respectively. Subgroup analyses based on the sample types (saliva-, serum- and plasma-based) showed no differences in the diagnostic accuracy of each subgroup. An independent meta-analysis of eight articles was conducted to evaluate the diagnostic accuracy of miRNAs in patients with esophageal squamous cell carcinoma, with a pooled sensitivity of 0.77, specificity of 0.83, PLR of 4.4, NLR of 0.27, diagnostic odds ratio of 16, and area under the curve of 0.87. In conclusion, this meta-analysis demonstrates the feasibility of using miRNAs as non-invasive biomarkers to discriminate esophageal cancer from healthy controls. However, further high-quality studies on more clearly defined esophageal cancer patient are needed to confirm our conclusion.

Cyclin D1 is a strong prognostic factor for survival in pancreatic cancer: analysis of CD G870A polymorphism, FISH and immunohistochemistry

BACKGROUND AND OBJECTIVE

Cyclin D1 is an important regulator protein for the G1-S cell cycle phase transition. The aim of this trial was to evaluate the impact of the CCND1 polymorphism G870A and corresponding protein expression and CCND1 amplification on the survival of the patients.

METHODS

425 patients with ductal pancreatic adenocarcinoma who underwent resection were included after histopathological confirmation. DNA was analyzed for Cyclin D1 polymorphisms, immunhistochemical examination and fluorescence in situ hybridization analysis of the tumor were performed.

RESULTS

Overall, the mean survival was 22.9 months (20.5-25.3). The survival in patients with Cyclin D1 G870A polymorphism Adenine/Adenine was 15.1 months (95% CI 11.3-18.9), 21.5 months (17.4-25.6) for Adenine/Guanine, and 29.4 months (95% CI 23.8-35.0) for Guanine/Guanine (P = 0.003). A shorter survival was associated with strong/moderate protein expression in immunohistochemistry (IHC) compared to weak/no expression (P = 0.028). Additionally, a significant coherency between unfavourable polymorphism (AA/AG) and increased protein expression was detected (P = 0.005).

CONCLUSIONS

A strong impact on survival of Cyclin D1 G870A polymorphism and the detected corresponding protein expression was found. The biological mechanism of CCND1 in carcinogenesis has not been fully examined; but at present Cyclin D1 seems to be an interesting biomarker for the prognosis of ductal adenocarcinoma.

Plasma microRNA profiles: identification of miR-25 as a novel diagnostic and monitoring biomarker in oesophageal squamous cell carcinoma

Background:

Recent studies have demonstrated that microRNAs are stably detectable in plasma/serum because of their binding to specific proteins or being packaged in secretory particles. This study was designed to detect novel microRNAs in plasma for cancer detection and monitoring using microRNA array-based approaches in oesophageal squamous cell carcinoma (ESCC) patients.

Methods:

Through the integration of two Toray 3D-Gene microRNA array-based approaches to compare plasma microRNA levels between ESCC patients and healthy volunteers and between preoperative and postoperative ESCC patients, we identified a novel plasma biomarker in ESCC.

Results:

(1) Eight upregulated and common microRNAs (miR-15b, 16, 17, 25, 19b, 20a, 20b, and 106a) were selected using two high-resolution microRNA array approaches. (2) Test-scale analyses by quantitative RT–PCR validated a significant higher levels of plasma miR-19b (P=0.0020) and miR-25 (P=0.0030) in ESCC patients than controls. However, a significant correlation was observed between plasma miR-19b levels and concentrations of red blood cells (P=0.0073) and haemoglobin (P=0.0072). (3) miR-25 expression was found to be significantly higher in ESCC tissues (P=0.0157) and ESCC cell lines (P=0.0093) than in normal tissues and fibroblasts. (4) In a large-scale validation analysis, plasma miR-25 levels were significantly higher in 105 preoperative (P<0.0001) ESCC patients who underwent curative oesophagectomy and 20 superficial ESCC patients who underwent endoscopic resection (P<0.0001) than in 50 healthy volunteers. (5) Plasma miR-25 levels were significantly reduced in postoperative samples than in preoperative samples (P<0.0005) and were significantly increased during ESCC recurrences (P=0.0145).

Conclusions:

Plasma miR-25 might be a clinically useful biomarker for cancer detection and the monitoring of tumour dynamics in ESCC patients.

Upregulation of SYF2 in esophageal squamous cell carcinoma promotes tumor cell proliferation and predicts poor prognosis

SYF2, also known as CCNDBP1-interactor or p29, is reported in pre-mRNA splicing and cell cycle progression. However, the role of SYF2 in esophageal squamous cell carcinoma (ESCC) development remains elusive. In the present study, Western blot and immunohistochemistry assays demonstrated that SYF2 was overexpressed in ESCC tumor tissues and cell lines. In addition, immunohistochemistry analysis revealed that SYF2 expression was positively correlated with tumor grade and predicted poor prognosis of ESCC. In vitro studies using serum starvation-refeeding experiment and SYF2-siRNA transfection assay demonstrated that SYF2 expression promoted proliferation of ESCC cells, while SYF2 knockdown led to decreased cell growth rate and colony formation resulted from growth arrest of cell cycle at G0/G1 phase. Furthermore, our results indicated that SYF2 can down-regulate the sensitivity of ESCC cells for cisplatin. Our findings for the first time supported that SYF2 might play an important role in the regulation of ESCC proliferation and would provide a novel therapeutic strategy against human ESCC.

Clinical impact of predicting CCND1 amplification using plasma DNA in superficial esophageal squamous cell carcinoma

BACKGROUND

This study was designed to evaluate the clinical benefit of predicting the cyclin D1 (CCND1) status using cell-free plasma DNA in superficial esophageal squamous cell carcinoma (ESCC) patients.

METHODS

The ratio of the CCND1 (11q13) dosage to the DRD2 (11q22-23) dosage (C/D ratio) as the CCND1 copy number was evaluated. This study was divided into three steps: (1) demonstration of the feasibility, (2) evaluation of whether the plasma C/D ratio assay could monitor tumor dynamics, and (3) a validation study in 63 consecutive superficial ESCC (pTis-T1) patients and 40 healthy volunteers.

RESULTS

(1) The plasma C/D ratio was significantly higher (p = 0.0369) in superficial ESCC patients than in the controls in a preliminary test. (2) The high plasma C/D ratio appeared to reflect the tumor levels of the CCND1 status and was reduced in postoperative plasma samples (p = 0.1154) and samples following endoscopic resection (p = 0.0845). (3) Validation analysis revealed that the plasma C/D ratio was significantly higher in superficial ESCC patients than in controls (p < 0.0001). The frequency of recurrence was significantly higher (p = 0.0198), and recurrence-free survival was significantly shorter (p = 0.0075) in patients with a high plasma C/D ratio. Moreover, a high C/D ratio was shown to be an independent risk factor for recurrence on multivariate analysis [p = 0.0334; odds ratio 10.58 (range 1.203-93.23)].

CONCLUSION

The prediction of CCND1 amplification by plasma DNA may be a new complementary clinical biomarker for recurrence in patients with superficial ESCC.

Proapoptotic and Antiproliferative Effects of Thymus caramanicus on Human Breast Cancer Cell Line (MCF-7) and Its Interaction with Anticancer Drug Vincristine

Thymus caramanicus Jalas is one of the species of thymus that grows in the wild in different regions of Iran. Traditionally, leaves of this plant are used in the treatment of diabetes, arthritis, and cancerous situation. Therefore, the present study was designed to investigate the selective cytotoxic and antiproliferative properties of Thymus caramanicus extract (TCE). MCF-7 human breast cancer cells were used in this study. Cytotoxicity of the extract was determined using MTT and neutral red assays. Biochemical markers of apoptosis (caspase 3, Bax, and Bcl-2) and cell proliferation (cyclin D1) were evaluated by immunoblotting. Vincristine was used as anticancer control drug in extract combination therapy. The data showed that incubation of cells with TCE (200 and 250 μg/mL) significantly increased cell damage, activated caspase 3 and Bax/Bcl2 ratio. In addition, cyclin D1 was significantly decreased in TCE-treated cells. Furthermore, concomitant treatment of cells with extract and anticancer drug produced a significant cytotoxic effect as compared to extract or drugs alone. In conclusion, thymus extract has a potential proapoptotic/antiproliferative property against human breast cancer cells and its combination with chemotherapeutic agent vincristine may induce cell death effectively and be a potent modality to treat this type of cancer.

Clinical impact of circulating miR-18a in plasma of patients with oesophageal squamous cell carcinoma

Background:

Several recent studies demonstrated that microRNAs are stably detectable in plasma/serum. We tested whether miR-18a, which is located in the miR-17-92 cluster and reported to be highly expressed in tissues of oesophageal squamous cell carcinoma (ESCC), served as a plasma biomarker in patients with ESCC.

Methods:

This study was divided into three steps: (1) confirmation of higher miR-18a levels in primary ESCC tissues and cell lines than normal ESCC tissues and a human fibroblast cell line. (2) Evaluation of the plasma miR-18a assay using quantitative RT–PCR by comparing results from 106 consecutive patients with ESCC and 54 healthy volunteers. (3) Evaluation of the assay for monitoring tumour dynamics in patients with ESCC.

Results:

(1) Expression of miR-18a was significantly higher in ESCC tissues (P=0.0020) and ESCC cell lines (P=0.0121) than normal tissues and fibroblasts. (2) Plasma concentrations of miR-18a were significantly higher in ESCC patients than healthy volunteers (P<0.0001; ESCC patients vs healthy volunteers (mean±s.d.): 11.77±13.45 vs 0.73±0.54 amol μl⁻¹). The value of the area under the receiver-operating characteristic (ROC) curve (AUC) was 0.9449. Furthermore, the ROC curves to detect early ESCC such as pTis-1 and pStage0-I showed AUCs of 0.9479 and 0.9642, respectively. (3) Plasma levels of miR-18a were significantly lower in postoperative samples than preoperative samples (P=0.0076).

Conclusion:

Plasma miR-18a may be a very useful biomarker for cancer detection and the monitoring of tumour dynamics in patients with ESCC.

The radiation-sensitizing effect of flavopiridol in the esophageal cancer cell line Eca109

Flavopiridol is a cyclin-dependent kinase inhibitor. It has shown an antitumor effect against several cancers. In the present study, the radiation-sensitizing effect of flavopiridol was investigated in an esophageal squamous carcinoma cell line, Eca109. The growth inhibitory rate of Eca109 with flavopiridol was determined using the MTT and the radio-sensitizing rate using clonogenic survival assays. The cell cycle distribution and the rate of apoptosis were measured using flow cytometry. The proteins cyclin D1, ERK/pERK, caspase-3, Bax and Bcl-2 were detected using western blot analysis to elucidate the mechanism of the radiosensitization effect. MTT assay showed that flavopiridol inhibited the survival rate of Eca109 cells and the effect was dose-dependent. Its IC₅₀ was 193.3 nmol/l. The result of the clonogenic survival revealed that flavopiridol enhanced the radiosensitivity of Eca109 cells and the sensitization enhancement ratio (SER) was 1.194 at 0.2×IC_50. Moreover, we detected that the cells treated with flavorpiridol were arrested at the G₂/M phase and the apoptosis caused by radiation was increased. In addition, the proteins caspase-3 and Bax in cells treated with flavopiridol were upregulated, while cyclin D1 and Bcl-2 were downregulated. In conclusion, flavopiridol may enhance the radiosensitivity of Eca109 cells and the radiosensitizing effect of flavopiridol may be mediated by decreasing the levels of the cyclin D1 protein, thus increasing the percentage of cells at G₂/M phase.

Molecular mechanisms of curcumin action: gene expression

Curcumin derived from the tropical plant Curcuma longa has a long history of use as a dietary agent, food preservative, and in traditional Asian medicine. It has been used for centuries to treat biliary disorders, anorexia, cough, diabetic wounds, hepatic disorders, rheumatism, and sinusitis. The preventive and therapeutic properties of curcumin are associated with its antioxidant, anti-inflammatory, and anticancer properties. Extensive research over several decades has attempted to identify the molecular mechanisms of curcumin action. Curcumin modulates numerous molecular targets by altering their gene expression, signaling pathways, or through direct interaction. Curcumin regulates the expression of inflammatory cytokines (e.g., TNF, IL-1), growth factors (e.g., VEGF, EGF, FGF), growth factor receptors (e.g., EGFR, HER-2, AR), enzymes (e.g., COX-2, LOX, MMP9, MAPK, mTOR, Akt), adhesion molecules (e.g., ELAM-1, ICAM-1, VCAM-1), apoptosis related proteins (e.g., Bcl-2, caspases, DR, Fas), and cell cycle proteins (e.g., cyclin D1). Curcumin modulates the activity of several transcription factors (e.g., NF-κB, AP-1, STAT) and their signaling pathways. Based on its ability to affect multiple targets, curcumin has the potential for the prevention and treatment of various diseases including cancers, arthritis, allergies, atherosclerosis, aging, neurodegenerative disease, hepatic disorders, obesity, diabetes, psoriasis, and autoimmune diseases. This review summarizes the molecular mechanisms of modulation of gene expression by curcumin.

Prognostic and predictive roles for circulating biomarkers in gastrointestinal cancer

Circulating tumor cells (CTCs) and circulating free DNA (cfDNA) have been studied as promising prognostic and predictive tumor-derived biomarkers in the bloodstream of patients with gastrointestinal malignancies because they may be an alternative noninvasive tool to tumor tissue biopsies. Quantification and molecular characterization of CTCs and cfDNA may provide additional insights into cancer biology, potentially revealing novel targets to individualize cancer care. The present article aims to review the biology and current methods to assess CTCs and cfDNA, and the efforts to establish both tumor-derived biomarkers as prognostic and predictive factors in esophageal, gastric and colorectal cancer.

Circulating microRNAs in plasma of patients with oesophageal squamous cell carcinoma

BACKGROUND

Several recent studies demonstrated that microRNAs (miRNAs) are stably detectable in plasma/serum. We hypothesised that plasma miRNAs concentrations contributed to potential biomarkers in patients with oesophageal squamous cell carcinoma (ESCC).

METHODS

We selected three oncogenic miRNAs (miR-21, miR-184, miR-221) and one tumour suppressive miRNA (miR-375), which are frequently reported in squamous cell carcinoma, as candidate targets for this plasma miRNA assay. This study was divided into three steps: (1) Determination of appropriate plasma miRNAs in preliminary tests. (2) Evaluation of whether the plasma miRNA assays could monitor tumour dynamics. (3) Validation study on the clinical application of plasma miRNA assays in 50 ESCC patients and 20 healthy volunteers.

RESULTS

(1) In preliminary tests, the plasma level of miR-21 was significantly higher (P=0.0218) and that of miR-375 (P=0.0052) was significantly lower in ESCC patients than controls. (2) The high plasma miR-21 levels reflected tumour levels in all cases (100%). The plasma level of miR-21 was significantly reduced in postoperative samples (P=0.0058). (3) On validation analysis, the plasma level of miR-21 tended to be higher in ESCC patients (P=0.0649), while that of miR-375 was significantly lower (P<0.0001) and the miR-21/miR-375 ratio was significantly higher (P<0.0001) in ESCC patients than in controls. The value of the area under the receiver-operating characteristic curve (AUC) was 0.816 for the miR-21/miR-375 ratio assay. Patients with a high plasma level of miR-21 tended to have greater vascular invasion (P=0.1554) and to show a high correlation with recurrence (P=0.0164).

CONCLUSION

Detection of circulating miRNAs might provide new complementary tumour markers for ESCC.

Ubiquitin-dependent proteolysis in G1/S phase control and its relationship with tumor susceptibility

Cell division depends upon the coordinated action of positive and negative regulatory factors that ensure high fidelity replication of the genome and its equivalent separation into daughter cells following cytokinesis. The role of positive factors such as the cyclin dependent kinases in promoting cell division is firmly established, as is the function of CDK inhibitors and phosphatases that antagonize CDKs. In addition to these, regulated protein destruction is now appreciated as essential for temporal regulation of cell cycle transitions. Protein degradation serves as an irreversible switch that ensures temporally regulated cell cycle transitions. Signal-dependent regulation of protein degradation is best understood with regard to the 26S proteasome. Proteins are directed to this machine subsequent to enzymatic transfer of a highly conserved small polypeptide, ubiquitin. The focus of this review is the regulatory molecules that direct the regulated attachment of ubiquitin, polyubiquitylation, to proteins destined for degradation as cells transition through the G1 phase into S-phase. During the past decade, it has become increasingly apparent that these molecules are critical mediators of normal cell proliferation and as such they are frequently deregulated in human cancers.

Prediction of CCND1 amplification using plasma DNA as a prognostic marker in oesophageal squamous cell carcinoma

Background:

We aimed to develop a new biomarker to predict cyclin D1 (CCND1) status using plasma DNA in oesophageal squamous cell carcinoma (ESCC) patients.

Methods:

We evaluated the ratio of the CCND1 (11q13) dosage to the dopamine receptor D2 (DRD2; 11q22-23) dosage (C/D ratio) as CCND1 copy number. This study was divided into three steps: (1) Determination of a cutoff value for the C/D ratio in test scale; (2) Comparison of the C/D ratio in between plasma samples and cancer tissues in ESCC patients showing high plasma C/D ratio; (3) Validation study of the clinical application of the plasma C/D ratio as a diagnostic and prognostic marker, by comparing with clinicopathologic factors in 96 ESCC patients.

Results:

The plasma C/D ratio was significantly higher in the ESCC group than the controls (P=0.0134). A high plasma C/D ratio reflected the tumour C/D ratio, and significantly correlated with a poorer prognosis (P=0.0186). Moreover, the high C/D ratio was found to be an independent prognostic factor on multivariate analysis (P=0.0266; hazard ratio 5.988).

Conclusion:

Prediction of CCND1 amplification using plasma DNA is thought to be a promising prognostic biomarker in ESCC patients.

Genomic biomarkers for molecular imaging: predicting the future

Over the past few decades, great strides have been made in anatomical imaging of disease that has led to their diagnosis with minimal invasion. Despite these advances, diseases such as cancer continue to take one human life every minute in the United States. Complimentary approaches that pertain directly to the genesis of the disease might contribute to its early diagnosis and subsequent management. In cancer, an array of molecular abnormalities leading to the modulations in expression of key proteins important in the cellular signaling pathways and cell proliferation has been identified. These specific disease fingerprints, biomarkers, are overexpressed on malignant cell surfaces or within the cytoplasm, and they provide unique targets that are promising for improving cancer diagnosis and therapy. We and others have designed, synthesized, and evaluated some novel probes specific for those oncogenes and oncogene product biomarkers for PET and SPECT molecular imaging of certain types of cancers. This article briefly describes this approach and gives specific examples that depict the ability of molecular imaging to detect occult lesions not detectable by current scintigraphic approaches. The article also outlines a few examples predicting other possible applications of targeting such specific probes not yet used.

Role of curcumin in health and disease

Curcumin (diferuloylmethane) is an orange-yellow component of turmeric (Curcuma longa), a spice often found in curry powder. In recent years, considerable interest has been focused on curcumin due to its use to treat a wide variety of disorders without any side effects. It is one of the major curcuminoids of turmeric, which impart its characteristic yellow colour. It was used in ancient times on the Indian subcontinent to treat various illnesses such as rheumatism, body ache, skin diseases, intestinal worms, diarrhoea, intermittent fevers, hepatic disorders, biliousness, urinary discharges, dyspepsia, inflammations, constipation, leukoderma, amenorrhea, and colic. Curcumin has the potential to treat a wide variety of inflammatory diseases including cancer, diabetes, cardiovascular diseases, arthritis, Alzheimer's disease, psoriasis, etc, through modulation of numerous molecular targets. This article reviews the use of curcumin for the chemoprevention and treatment of various diseases.

Comparative genomic hybridization analysis of genetic aberrations associated with development of esophageal squamous cell carcinoma in Henan, China

AIM: To characterize cytogenetic alterations in esophageal squamous cell carcinoma (ESCC) and its metastasis.

METHODS: A total of 37 cases of primary ESCC and 15 pairs of primary ESCC tumors and their matched metastatic lymph nodes cases were enrolled from Linzhou, the high incidence area for ESCC in Henan, northern China. The comparative genomic hybridization (CGH) was applied to determine the chromosomal aberrations on the DNA extracted from the frozen ESCC and metastatic lymph node samples from these patients.

RESULTS: CGH showed chromosomal aberrations in all the cases. In 37 cases of primary ESCC, chromosomal profile of DNA copy number was characterized by frequently detected gains at 8q (29/37, 78%), 3q (24/37, 65%), 5p (19/37, 51%); and frequently detected losses at 3p (21/37, 57%), 8p and 9q (14/37, 38%). In 15 pairs of primary ESCC tumors and their matched metastatic lymph node cases, the majority of the chromosomal aberrations in both primary tumor and metastatic lymph node lesions were consistent with the primary ESCC cases, but new candidate regions of interest were also detected. The most significant finding is the gains of chromosome 6p with a minimum high-level amplification region at 6p12-6q12 in 7 metastatic lymph nodes but only in 2 corresponding primary tumors (P = 0.05) and 20p with a minimum high-level amplification region at 20p12 in 11 metastatic lymph nodes but only in 5 corresponding primary tumors (P < 0.05). Another interesting finding is the loss of chromosome 10p and 10q in 8 and 7 metastatic lymph nodes but only in 2 corresponding primary tumors (P < 0.05).

CONCLUSION: Using the CGH technique to detect chromosomal aberrations in both the primary tumor and its metastatic lymph nodes of ESCC, gains of 8q, 3q and 5p and loss of 3p, 8p, 9q and 13q were specifically implicated in ESCC in Linzhou population. Gains of 6p and 20p and loss of 10pq may contribute to the lymph node metastasis of ESCC. These findings suggest that the gains and losses of chromosomal regions may contain ESCC-related oncogenes and tumor suppressor genes and provide important theoretic information for identifying and cloning novel ESCC-related oncogenes and tumor suppressor genes.

Comparative genomic hybridization: comparison between esophageal squamous cell carcinoma and gastric cardia adenocarcinoma from a high-incidence area for both cancers in Henan, northern China

Esophageal squamous cell carcinoma (SCC) remains the leading cause of cancer related deaths in Linzhou (formerly Linxian), the highest incidence area for esophageal cancer (EC) in Henan, northern China. In China, gastric cardia adenocarcinoma (GCA) shares very similar geographic distribution with SCC, suggesting the possibility of similar risk factors involved in SCC and GCA carcinogenesis in these areas. However, the underlying genetic alterations for esophageal and gastric cardia carcinogenesis, especially for the molecular difference between SCC and GCA, are largely unknown. The present study was thus undertaken to determine the difference in chromosomal aberrations in SCC (n = 37) and GCA (n = 31) using the comparative genomic hybridization method (CGH). All the patients were from Linzhou, Henan, a high-risk geographic region for both SCC and GCA. CGH results showed that chromosomal aberrations with different degrees were identified both in SCC and GCA. In SCC, chromosomal profile of DNA copy number was characterized by most frequently detected gains at 8q (29/37, 78%), 3q (24/37, 65%) and 5p (19/37, 51%); and frequently detected losses at 3p (21/37, 57%), 8p and 9q (14/37, 38%). In GCA, the frequently detected gains were identified at 20q (13/31, 42%), 6q (12/31, 39%) and 8q (11/31, 35%); the DNA copy number losses in GCA occurred frequently at 17p (17/31, 55%), 19p (15/31, 48%) and 1p (14/31, 45%). Statistically, there were evident differences between SCC and GCA in DNA copy number gains at 8q, 3q, 5p and 20q (P < 0.05) and in losses at 3p, 8p, 5q, 17p and 18q (P < 0.05). Gains at 8q were frequently observed in both SCC and GCA. Gains at 3q and 8p were frequently observed in TNM stage III of both SCC and GCA. The present CGH results provide candidate regions that may contain specific related genes involved in SCC and GCA in the Linzhou population. Gains at 8q, 3q and 5p and losses at 3p, 8p and 9q were specifically implicated in SCC; gains at 20q, 6q and 8q and losses at 17p, 19p and 1p were specifically implicated in GCA; gains at 8q were implicated in both SCC and GCA.

Identification of mutations that disrupt phosphorylation-dependent nuclear export of cyclin D1

Although cyclin D1 is overexpressed in a significant number of human cancers, overexpression alone is insufficient to promote tumorigenesis. In vitro studies have revealed that inhibition of cyclin D1 nuclear export unmasks its neoplastic potential. Cyclin D1 nuclear export depends upon phosphorylation of a C-terminal residue, threonine 286, (Thr-286) which in turn promotes association with the nuclear exportin, CRM1. Mutation of Thr-286 to a non-phosphorylatable residue results in a constitutively nuclear cyclin D1 protein with significantly increased oncogenic potential. To determine whether cyclin D1 is subject to mutations that inhibit its nuclear export in human cancer, we have sequenced exon 5 of cyclin D1 in primary esophageal carcinoma samples and in cell lines derived from esophageal cancer. Our work reveals that cyclin D1 is subject to mutations in primary human cancer. The mutations identified specifically disrupt phosphorylation of cyclin D1 at Thr-286, thereby enforcing nuclear accumulation of cyclin D1. Through characterization of these mutants, we also define an acidic residue within the C-terminus of cyclin D1 that is necessary for recognition and phosphorylation of cyclin D1 by glycogen synthase kinase-3 beta. Finally, through construction of compound mutants, we demonstrate that cell transformation by the cancer-derived cyclin D1 alleles correlates with their ability to associate with and activate CDK4. Our data reveal that cyclin D1 is subject to mutations in primary human cancer that specifically disrupt phosphorylation-dependent nuclear export of cyclin D1 and suggest that such mutations contribute to the genesis and progression of neoplastic growth.

Silymarin and silibinin cause G1 and G2-M cell cycle arrest via distinct circuitries in human prostate cancer PC3 cells: a comparison of flavanone silibinin with flavanolignan mixture silymarin

Here, we assessed and compared the anticancer efficacy and associated mechanisms of silymarin and silibinin in human prostate cancer (PCA) PC3 cells; silymarin is comprised of silibinin and its other stereoisomers, including isosilybin A, isosilybin B, silydianin, silychristin and isosilychristin. Silymarin and silibinin (50-100 microg/ml) inhibited cell proliferation, induced cell death, and caused G1 and G2-M cell cycle arrest in a dose/time-dependent manner. Molecular studies showed that G1 arrest was associated with a decrease in cyclin D1, cyclin D3, cyclin E, cyclin-dependent kinase (CDK)4, CDK6 and CDK2 protein levels, and CDK2 and CDK4 kinase activity, together with an increase in CDK inhibitors (CDKIs) Kip1/p27 and Cip1/p21. Further, both agents caused cytoplasmic sequestration of cyclin D1 and CDK2, contributing to G1 arrest. The G2-M arrest by silibinin and silymarin was associated with decreased levels of cyclin B1, cyclin A, pCdc2 (Tyr15), Cdc2, and an inhibition of Cdc2 kinase activity. Both agents also decreased the levels of Cdc25B and cell division cycle 25C (Cdc25C) phosphatases with an increased phosphorylation of Cdc25C at Ser216 and its translocation from nucleus to the cytoplasm, which was accompanied by an increased binding with 14-3-3beta. Both agents also increased checkpoint kinase (Chk)2 phosphorylation at Thr68 and Ser19 sites, which is known to phosphorylate Cdc25C at Ser216 site. Chk2-specific small interfering RNA largely attenuated the silymarin and silibinin-induced G2-M arrest. An increase in the phosphorylation of histone 2AX and ataxia telangiectasia mutated was also observed. These findings indicate that silymarin and silibinin modulate G1 phase cyclins-CDKs-CDKIs for G1 arrest, and the Chk2-Cdc25C-Cdc2/cyclin B1 pathway for G2-M arrest, together with an altered subcellular localization of critical cell cycle regulators. Overall, we observed comparable effects for both silymarin and silibinin at equal concentrations by weight, suggesting that silibinin could be a major cell cycle-inhibitory component in silymarin. However, other silibinin stereoisomers present in silymarin also contribute to its efficacy, and could be of interest for future investigation.

Molecular targets of dietary agents for prevention and therapy of cancer

While fruits and vegetables are recommended for prevention of cancer and other diseases, their active ingredients (at the molecular level) and their mechanisms of action less well understood. Extensive research during the last half century has identified various molecular targets that can potentially be used not only for the prevention of cancer but also for treatment. However, lack of success with targeted monotherapy resulting from bypass mechanisms has forced researchers to employ either combination therapy or agents that interfere with multiple cell-signaling pathways. In this review, we present evidence that numerous agents identified from fruits and vegetables can interfere with several cell-signaling pathways. The agents include curcumin (turmeric), resveratrol (red grapes, peanuts and berries), genistein (soybean), diallyl sulfide (allium), S-allyl cysteine (allium), allicin (garlic), lycopene (tomato), capsaicin (red chilli), diosgenin (fenugreek), 6-gingerol (ginger), ellagic acid (pomegranate), ursolic acid (apple, pears, prunes), silymarin (milk thistle), anethol (anise, camphor, and fennel), catechins (green tea), eugenol (cloves), indole-3-carbinol (cruciferous vegetables), limonene (citrus fruits), beta carotene (carrots), and dietary fiber. For instance, the cell-signaling pathways inhibited by curcumin alone include NF-kappaB, AP-1, STAT3, Akt, Bcl-2, Bcl-X(L), caspases, PARP, IKK, EGFR, HER2, JNK, MAPK, COX2, and 5-LOX. The active principle identified in fruit and vegetables and the molecular targets modulated may be the basis for how these dietary agents not only prevent but also treat cancer and other diseases. This work reaffirms what Hippocrates said 25 centuries ago, let food be thy medicine and medicine be thy food.

Numerical abnormalities of the Cyclin D1 gene locus on chromosome 11q13 in non-melanoma skin cancer

Deregulation of the cell-cycle G1-restriction point control via abnormalities of Rb-pathway components is a frequent event in the formation of cancer. The aim of this study was to evaluate numerical aberrations of the Cyclin D1 (CCND1, PRAD1, bcl-1) gene locus at chromosome 11q13 in basal cell carcinomas (BCCs) and squamous cell carcinomas (SCCs) of the skin and to compare it with the Cyclin D1 protein expression. Fluorescence in situ hybridization with DNA-probes specific for the Cyclin D1 gene locus and the centromere of chromosome 11 as well as immunostaining for Cyclin D1 protein was applied on 5 microm serial paraffin sections. Six of the 30 (20%) SCCs showed additional Cyclin D1 gene copies and 2/30 (6.6%) cases had a loss of the Cyclin D1 gene locus in relation to the centromere 11 number. In contrast, only one of the 14 BCCs (7%) showed one additional Cyclin D1 gene copy in relation to the centromere 11 number. None of the BCCs demonstrated aneusomy for chromosome 11 in contrast to SCCs, where it was found in 21/30 (70%) cases. Twenty-six of the 30 (86.6%) cutaneous SCCs and 13/14 (93%) BCCs expressed Cyclin D1 protein. All SCCs and the BCC with additional Cyclin D1 gene copies showed positivity for Cyclin D1 protein. Both SCCs with less Cyclin D1 gene copies than centromere 11 signals showed a weak protein expression. Our findings suggest that numerical abnormalities of the Cyclin D1 gene locus could result in an altered gene-dose effect, possibly leading to an aberrant expression in affected tumor cells. This might result in deregulation of cell cycle control, eventually leading to uncontrolled cell cycle progression.

Flavopiridol as a radio-sensitizer for esophageal cancer cell lines

Flavopiridol is a synthetic flavone that has shown an antitumor effect against several cancers. Here, we investigated the in vitro effect of flavopiridol alone and the combined effect of low-dose flavopiridol plus radiation on esophageal squamous cell carcinoma cell lines. Esophageal squamous cell carcinoma cell lines (TE8, TE9 and KE4) were exposed to flavopiridol (0.05-400 nmol/L) for 48 h. Growth inhibition was evaluated by MTT assay, cell cycle distribution was determined by flow cytometry, and cyclin D1, Bcl-2 and Rb protein expression was detected by Western blotting. The effect of 0.05 nmol/L flavopiridol as a radio-sensitizer was determined by clonogenic assay. The IC50 was approximately 110-250 nmol/L. Exposure to 0.05 nmol/L flavopiridol for 48 h increased the G2/M population, while 300 nmol/L increased the G1 population. At a concentration of 300 nmol/L, nuclear fragmentation and chromatin condensation were observed in all three cell lines. Exposure to 300 nmol/L flavopiridol decreased the levels of cyclin D1 and Rb protein in all three cell lines and Bcl-2 protein was also decreased in TE8 and KE4 cells. Moreover, exposure to 0.05 nmol/L flavopiridol slightly decreased the levels of cyclin D1, Rb and Bcl-2 protein in KE4 cells. Flavopiridol treatment (0.05 nmol/L) enhanced the radio-sensitivity in all three cell lines. Low-dose flavopiridol augmented the response of esophageal squamous cell carcinoma cell lines to radiation. Administration of a low dose of flavopiridol could be a potent new therapeutic approach for improving the efficacy of radiotherapy against esophageal cancer.

Clinicopathological and Biological Characteristics of Esophageal Squamous Cell Carcinoma Associated with Head and Neck Cancer

OBJECTIVE

Esophageal cancer has been reported to be frequently associated with cancer of the head and neck. The iodine dye method is reportedly useful to detect early esophageal cancer. The aim of this study was to clarify clinicopathological and biological characteristics of esophageal squamous cell carcinoma associated with head and neck cancer (HN group).

METHODS

Thirty-seven patients of the HN group who underwent esophagectomy were examined clinicopathologically compared to 42 patients with esophageal cancer alone (SE group). All resected specimens were histologically studied after iodine dye staining, and p53 and cyclin D1 (CD1) expression were immunohistochemically examined in esophageal cancer.

RESULTS

The HN group had more multiple iodine-unstained lesions and multiple primary cancers within the esophagus compared with the SE group (p = 0.0027, p = 0.067, respectively). There was no significant difference in smoking, drinking, family history and the other clinicopathological factors between the HN and SE groups. Coexpression of p53 and CD1 was found to be significant in the HN group (p = 0.03).

CONCLUSIONS

The coexistence of multiple iodine-unstained lesions, multiple cancers in the esophagus and overexpression of p53 and CD1 is suggested as a risk factor for the HN group.

Epidermal growth factor receptor and cyclin D1 are independently amplified and overexpressed in esophageal squamous cell carcinoma

PURPOSE

To assess the status of EGFR, HER-2, and CCND1 at the gene and protein levels in esophageal squamous cell carcinoma.

METHODS

Dual-color FISH assays were performed using DNA probes for EGFR/CEP 7, HER-2/CEP 17, and CCND1/CEP 11. The respective proteins, furthermore, was assessed in IHC assays and correlated with patient and tumor characteristics.

RESULTS

From 55 ESCCs, 8 (15%) tumors showed gene amplification and 20 (36%) had gene overrepresentation (balanced gene and chromosome 7 polysomy) for EGFR. High-level protein expression was frequent (49%), positively correlated with gene copy numbers (kappa=0.4), and associated with well-differentiated histology (p=0.02). For HER-2, gene amplification was detected in a single tumor (2%) and protein overexpression was rare (9%). CCND1 gene was amplified in 23 (42%) tumors; likewise, CCND1 protein overexpression was common (58%) and prevailed in gene overrepresentation or amplification. Only 1 patient showed gene amplification for both EGFR and CCND1. Survival was not associated with EGFR or CCND1 gene/protein status, whereas negative patients for HER-2 protein had a better survival than positive patients (p=0.04).

CONCLUSIONS

Frequent overexpression and gene amplification of EGFR and CCND1 make these molecules and their pathways potential therapeutic targets for ESCC. In addition, EGFR and CCND1 appeared to be independently altered suggesting alternative mechanisms for pathway activation. Therapeutic agents targeting these molecules are urged to be tested in clinical trials and comprehensive biological analyses should be included to properly interpret the outcome.

Effects of Acyclic Retinoid on Growth, Cell Cycle Control, Epidermal Growth Factor Receptor Signaling, and Gene Expression in Human Squamous Cell Carcinoma Cells

We described recently the growth inhibitory effects of the novel compound acyclic retinoid (ACR) in human hepatoma cell lines (M. Suzui et al., Cancer Res., 62: 3997-4006, 2002). In this study we examined the cellular and molecular effects of ACR on human squamous cell carcinoma (SCC) cells. ACR inhibited growth of the esophageal SCC cell line HCE7, and the head and neck SCC cell lines YCU-N861 and YCU-H891, with IC(50) values of approximately 10, 25, and 40 microM, respectively. Detailed studies were then done with HCE7 cells. Treatment of these cells with 10 microM ACR caused an increase of cells in G(0)-G(1) and induced apoptosis. This was associated with two phases of molecular events. During phase 1, which occurred within 6-12 h, there was an increase in the retinoic acid receptor beta (RARbeta) and p21(CIP1) proteins, and their corresponding mRNAs, and a decrease in the hyperphosphorylated form of the retinoblastoma protein. During phase 2, which occurred at approximately 24 h, there was a decrease in the cellular level of transforming growth factor alpha, and the phosphorylated (i.e., activated) forms of the epidermal growth factor receptor, Stat3, and extracellular signal-regulated kinase proteins, and a decrease in both cyclin D1 protein and mRNA. Reporter assays indicated that ACR inhibited the transcriptional activity of the cyclin D1, c-fos, and activator protein promoters. On the other hand, ACR markedly stimulated the activity of a retinoic acid response element-CAT reporter when the cells were cotransfected with a RARbeta expression vector. A hypothetical model explaining these two phases is presented. The diverse effects that we obtained with ACR suggest that this agent might be useful in the chemoprevention and/or therapy of human SCCs.

Tissue Microarray Analysis of Cyclin D1 Gene Amplification and Gain in Colorectal Carcinomas

Colorectal cancer is one of the most common neoplastic diseases and one of the leading causes of cancer-related deaths. Elevated beta-catenin levels in colorectal cancer result in the binding of beta-catenin to LEF-1 and increased transcriptional activation of the CCND1 gene. Overexpression of cyclin D1 is observed in one third of colorectal tumors. CCND1 amplification is the main cause of protein overexpression in numerous human carcinomas. In colorectal cancer, however, no CCND1 amplification has been reported so far. The aim of this study was to determine the frequency of CCND1 amplifications and gains in a large number of colorectal carcinomas, arranged in a tissue microarray, in order to assess their role in colorectal cancer development. The copy number changes, detected by fluorescence in situ hybridization, were predominantly gains (7.6%) and only rarely amplifications (2.5%). In colorectal cancer, the CCND1 copy number increase was neither associated with the tumor phenotype (stage and grade) nor with the tumor localization (colon, rectum or sigmoid colon). In conclusion, even in a small number of colorectal tumors, CCND1 gene amplification is a possible mechanism for the increase in cyclin D1 oncoprotein.

Primary adenocarcinomas of lower esophagus, esophagogastric junction and gastric cardia: in special reference to China

Gastric cardia adenocarcinoma (GCA) is an under-studied subject. The pathogenesis, molecular changes in the early stage of carcinogenesis and related risk factors have not been well characterized. There is evidence, however, that GCA differs from cancer of the rest of the stomach in terms of natural history and histopathogenesis. Adenocarcinomas of the lower esophagus, esophagogastric junction (EGJ) and gastric cardia have been given much attention because of their increasing incidences in the past decades, which is in striking contrast with the steady decrease in distal stomach adenocarcinoma. In China, epidemiologically, GCA shares very similar geographic distribution with esophageal squamous cell carcinoma (SCC), especially in Linzhou (formerly Linxian County), Henan Province, North China, the highest incidence area of esophageal SCC in the world. Historically, both GCA and SCC in these areas were referred to as esophageal cancer (EC) by the public because of the common syndrome of dysphagia. In Western countries, Barrett's esophagus is very common and has been considered as an important precancerous lesion of adenocarcinoma at EGJ. Because of the low incidence of Barrett's esophagus in China, it is unlikely to be an important factor in early stage of EGJ adenocarcinoma development. However, Z line up-growth into lower esophagus may be one of the characteristic changes in these areas in early stage of GCA development. Whether intestinal metaplasia (IM) is a premalignant lesion for GCA is still not clear. Higher frequency of IM observed at adjacent GCA tissues in Henan suggests the possibility of IM as a precancerous lesion for GCA in these areas. Molecular information on GCA, especially in early stage, is very limited. The accumulated data about the changes of tumor suppressor gene, such as p53 mutation, and ontogeny, such as C-erbB2, especially the similar alterations in GCA and SCC in the same patient, indicated that there might be some similar risk factors, such as nitrosamine, involved in both GCA and SCC in Henan population. The present observations also suggest that GCA should be considered as a distinct entity.

Curcumin-induced suppression of cell proliferation correlates with down-regulation of cyclin D1 expression and CDK4-mediated retinoblastoma protein phosphorylation

Cyclin D1 is a proto-oncogene that is overexpressed in many cancers including breast and prostate. It plays a role in cell proliferation through activation of cyclin-dependent kinases. Curcumin, a diferuloylmethane, is a chemopreventive agent known to inhibit the proliferation of several breast and prostate cancer cell lines. It is possible that the effect of curcumin is mediated through the regulation of cyclin D1. In the present report we show that inhibition of the proliferation of various prostate, breast and squamous cell carcinoma cell lines by curcumin correlated with the down-regulation of the expression of cyclin D1 protein. In comparison, the down-regulation by curcumin of cyclin D2 and cyclin D3 was found only in selective cell lines. The suppression of cyclin D1 by curcumin led to inhibition of CDK4-mediated phosphorylation of retinoblastoma protein. We found that curcumin-induced down-regulation of cyclin D1 was inhibited by lactacystin, an inhibitor of 26S proteosome, suggesting that curcumin represses cyclin D1 expression by promoting proteolysis. We found that curcumin also down-regulated mRNA expression, thus suggesting transcriptional regulation. Curcumin also inhibited the activity of the cyclin D1 promoter-dependent reporter gene expression. Overall our results suggest that curcumin down-regulates cyclin D1 expression through activation of both transcriptional and post-transcriptional mechanisms, and this may contribute to the antiproliferative effects of curcumin against various cell types.

The future of therapy for nonseminomatous germ cell tumors

This article has reviewed recent advances in understanding the molecular mechanisms of germ cell transformation, germ cell tumor differentiation, and germ cell tumor chemotherapy sensitivity and resistance. Future developments should include the following: The use of high-throughput techniques to assess tumor biology and evaluate new markers will allow more sophisticated assessment of prognosis. Future therapy will use oligonucleotide chips, perhaps specific to germ cell tumors or gene products associated with drug resistance, to assign treatment (radiation, RPLND, chemotherapy). The pathways associated with metastases and resistance will either replace or amplify the current risk algorithms and the clinician's ability to select therapy. The same high-throughput techniques will identify critical molecules and pathways, providing new specific treatment targets. Cell cycle-specific targets are an ideal focus of study, because genes abrogating normal cell cycle control and promoting germ cell tumorigenesis are increasingly identified. In germ cell tumors, CCND2 and KIT are open to study. Molecular and genetic markers of differentiation are additional resistance markers and should be a focus of study. In this context, the treatment of malignant transformation and the prediction of teratoma at metastatic sites will take on a greater importance. Over the past 2 decades, the treatment of germ cell tumors has become well-defined. Further improvement requires that investigators find new markers corresponding to tumor phenotype. This achievement will prevent unnecessary treatment in patients destined to have a favorable outcome, and will target biologically unfavorable or resistant disease for new therapy developed specifically to target the molecular or genetic defects that disrupt normal cell cycle control.

Oxaliplatin in combination with protracted-infusion fluorouracil and radiation: report of a clinical trial for patients with esophageal cancer

PURPOSE

To identify a dose and schedule of oxaliplatin (OXP) to be safely administered in combination with protracted-infusion (PI) fluorouracil (5-FU) and external-beam radiation therapy (XRT) for patients with primary esophageal carcinoma (EC).

PATIENTS AND METHODS

Eligibility included therapeutically naïve EC patients with clinical disease stages II, III, or IV. Initial doses and schedules for cycle 1 consisted of OXP 85 mg/m(2) on days 1, 15, and 29; PI 5-FU 180 mg/m(2) for 24 hours for 35 days; and XRT 1.8 Gy in 28 fractions starting on day 8. At completion of cycle 1, eligible patients could undergo an operation or begin cycle 2 without XRT. Postoperative patients were eligible for cycle 2. Stage IV patients were allowed three cycles in the absence of disease progression. OXP and 5-FU increases were based on dose-limiting toxicity (DLT) encountered in cohorts of three consecutive patients.

RESULTS

Thirty-eight eligible patients received therapy: 22 noninvasively staged as IV and 16 noninvasively staged as II and III. Thirty-six patients completed cycle 1, 29 patients started cycle 2, and 24 patients completed cycle 2. The combined-modality therapy was well tolerated, but DLT prevented OXP and 5-FU escalation. No grade 4 hematologic toxicity was noted. Eleven grade 3 and two grade 4 clinical toxicities were noted in eight patients. After cycle 1, 29 patients (81%) had no cancer in the esophageal mucosa. Thirteen patients underwent an operation with intent to resect the esophagus; five patients (38%) exhibited pathologic complete responses.

CONCLUSION

OXP 85 mg/m(2) on days 1, 15, and 29 administered with PI 5-FU and XRT is safe, tolerable, and seems effective against primary EC. The role of OXP in multimodality regimens against EC deserves further evaluation.

Role of molecular biology in the follow-up of patients who have Barrett's esophagus

At present, the follow-up of patients who have Barrett's esophagus (BE) should occur within the setting of an endoscopic biopsy surveillance program and with the frequency of surveillance as proposed by the American College of Gastroenterology. In the future, patients who have BE will be further stratified according to their risk for progression to invasive carcinoma. This stratification will permit the development of more rational surveillance programs. Models that incorporate epidemiologic risk factors, reflux symptoms, and endoscopic and histologic findings will likely include panels of biomarkers for further stratification of patients as low, intermediate, or high risk. Therefore, the challenge over the next decade will be to define the role of molecular markers in endoscopic surveillance strategies and to identify additional clinically relevant molecular markers for prognosis as intermediate markers for chemoprevention and as molecular targets for novel gene therapies.

Prognostic significance of CyclinD1 and E-Cadherin in patients with esophageal squamous cell carcinoma: multiinstitutional retrospective analysis. Research Committee on Malignancy of Esophageal Cancer, Japanese Society for Esophageal Diseases

BACKGROUND

Although many molecular biologic molecules have been analyzed for their prognostic influence on patients with esophageal cancer, previous studies have not been able to raise statistically significant prognostic factors.

STUDY DESIGN

Immunohistochemical analysis of CyclinD1 expression and E-Cadherin expression was performed retrospectively in 416 esophageal squamous cell cancer patients who underwent curative resection of esophageal cancer at 10 major surgical departments in Japan, where more than 30 esophagectomies are performed in a year. The prognostic impact of these molecules and their relationship to clinicopathologic data of the patients were evaluated.

RESULTS

Univariate analysis revealed that pN (pTNM), pT (pTNM), CyclinD1 expression, and E-Cadherin expression were significant prognostic factors, and multivariate analysis revealed that pN (risk ratio (RR) 2.19), pT (RR 3.35), CyclinD1 (RR 1.42), and E-Cadherin (RR 0.71) were significant prognostic factors. Combination analysis of these genes revealed that E-Cadherin-preserved and CyclinD1-negative patients had the best prognosis; E-Cadherin-reduced and CyclinD1-positive patients had the worst prognosis.

CONCLUSIONS

Increased CyclinD1 expression and reduced E-Cadherin expression were significant prognostic factors in patients with esophageal squamous cell carcinoma.

DNA ploidy and cyclin D1 expression in basal cell carcinoma of the head and neck

Basal cell carcinomas (BCCs) may be subdivided into primary with a favorable biologic course (BCC1) and recurrent and/or metastatic (BCC2). No clear association between primary tumor location, histologic subtype, or other clinicopathologic variables and predisposition for BCC2 has been found. Histopathologic criteria are limited for prognostication. To identify prognostic factors useful for planning therapy, we studied cyclin D1 immunohistochemical expression, DNA ploidy, and epiluminescence light microscopic (ELM) patterns in 60 cases of BCC (30 BCC1 and 30 BCC2) in the head and neck region, half of which were hyperpigmented. Cyclin D1 was absent in 27 cases, expressed at low level in 4 cases, and overexpressed in 30 cases. Seven BCCs were euploid, 28 exhibited a mixed cellular population, and 25 were aneuploid. Among aneuploid tumors, hypodiploidy was found in 12. Among the 30 pigmented carcinomas, only 15 showed a typical ELM pattern. No association between pigmentation and more aggressive biologic behavior of BCC was found. These results and follow-up data seem to indicate that an unfavorable outcome can be predicted by hyperexpression of cyclin D1, aneuploidy, and an atypical ELM pattern for pigmented cases. A definite hypodiploid peak was associated with worse prognosis. The analysis of cyclin D1 expression and DNA ploidy may help identify BCC with an aggressive phenotype and a poor clinical outcome.

Molecular biology of Barrett's adenocarcinoma

OBJECTIVE

To review the current knowledge on the genetic alterations involved in the development and progression of Barrett's esophagus-associated neoplastic lesions.

SUMMARY BACKGROUND DATA

Barrett's esophagus (BE) is a premalignant condition in which the normal squamous epithelium of the esophagus is replaced by metaplastic columnar epithelium. BE predisposes patients to the development of esophageal adenocarcinoma. Endoscopic surveillance can detect esophageal adenocarcinomas when they are early and curable, but most of the adenocarcinomas are detected at an advanced stage. Despite advances in multimodal therapy, the prognosis for invasive esophageal adenocarcinoma is poor. A better understanding of the molecular evolution of the Barrett's metaplasia to dysplasia to adenocarcinoma sequence may allow improved diagnosis, therapy, and prognosis.

METHODS

The authors reviewed data from the published literature to address what is known about the molecular changes thought to be important in the pathogenesis of BE-associated neoplastic lesions.

RESULTS

The progression of Barrett's metaplasia to adenocarcinoma is associated with several changes in gene structure, gene expression, and protein structure. Some of the molecular alterations already showed promise as markers for early cancer detection or prognostication. Among these, alterations in the p53 and p16 genes and cell cycle abnormalities or aneuploidy appear to be the most important and well-characterized molecular changes. However, the exact sequence of events is not known, and probably multiple molecular pathways interact and are involved in the progression of BE to adenocarcinoma.

CONCLUSIONS

Further research into the molecular biology of BE-associated adenocarcinoma will enhance our understanding of the genetic events critical for the initiation and progression of Barrett's adenocarcinoma, leading to more effective surveillance and treatment.

Evidence for a direct correlation between c-Jun NH2 terminal kinase 1 activation, cyclin D2 expression, and G(1)/S phase transition in the murine hybridoma 7TD1 cells

In this study we show that the addition of fresh culture medium to high-density growth-arrested 7TD1 cells induces a strong and transient stimulation of the c-Jun NH2 terminal kinase activity (Jun kinase/JNK), a marked increase in cyclin D2 expression, the phosphorylation of pRb, and the transition from G(1) to S phase. The stimulation of cyclin D2 expression and the induction of JNK activity appear to be the consequences of the alkalinization of the extracellular medium. Indeed both parameters (i) can be induced, regardless of cell dilution, by the addition of a weak base such as triethylamine, and (ii) are together inhibited by (N-ethyl-N-isopropyl)amiloride, a specific inhibitor of the Na(+)/H(+) exchanger. We provide a strong argument indicating the existence of a direct correlation between JNK1 activation and cyclin D2 stimulation. Indeed, we demonstrate that cyclin D2 expression is blocked by SB 202190, an agent known to inhibit both JNK and p38(MAPK), but not by SB 203580, a specific inhibitor of p38(MAPK). Furthermore, we also observed that DMSO and forskolin, two agents that inhibit the proliferation of 7TD1 cells, inhibit in parallel cyclin D2 and JNK1. Altogether our results suggest that (i) JNK1 participates in the signaling pathway which controls the expression of cyclin D2 and (ii) that the inhibition of JNK1 by DMSO and forskolin could explain, at least in part, the antiproliferative action of these drugs in 7TD1 cells.

Prospective study of cyclin D1 overexpression in Barrett's esophagus: association with increased risk of adenocarcinoma

BACKGROUND

Esophageal adenocarcinoma commonly arises from a precancerous condition, Barrett's esophagus, in which the normal squamous epithelium is replaced by a columnar cell-lined epithelium. Genetic alterations occurring in this process could serve as biomarkers for the risk of malignant progression, improve surveillance, and contribute to early diagnosis. We examined two potential biomarkers, cyclin D1 and p53, in a prospective cohort of Barrett's esophagus patients.

METHODS

A total of 307 patients were enrolled in an endoscopic surveillance cohort, and esophageal biopsy specimens were collected at each endoscopy. Incident cases of adenocarcinoma were matched to control patients within the cohort by duration of follow-up, age, sex, and length of columnar cell-lined epithelium at recruitment. Biopsy specimens were analyzed for cyclin D1 and p53 protein levels by immunohistochemistry. Statistical tests were two-sided.

RESULTS

A total of 12 cases of adenocarcinoma occurred within the follow-up period, and tumor biopsy specimens from 11 cases stained positive for cyclin D1. Biopsy specimens from eight of these patients taken at recruitment also stained positive for cyclin D1. A case-control analysis of biopsy specimens obtained at recruitment revealed a statistically significantly increased risk of progression to adenocarcinoma in Barrett's esophagus patients whose biopsy specimens were cyclin D1 positive (odds ratio [OR] = 6. 85; 95% confidence interval [CI] = 1.57-29.91; P =.0106) but not in patients whose biopsy specimens were p53 positive (OR = 2.99; 95% CI = 0.57-15.76; P =.197).

CONCLUSIONS

Cyclin D1-positive staining could be a useful biomarker in identifying Barrett's esophagus patients at high risk of esophageal adenocarcinoma. Given the complexity of genetic alterations in the natural history of this cancer, additional biomarkers will be required to increase the sensitivity and specificity of molecular diagnosis.

Control of cell cycle gene expression in bone development and during c-Fos-induced osteosarcoma formation

We have used c-Fos transgenic mice which develop osteosarcomas to determine the expression patterns of cyclins, cyclin-dependent kinases (CDKs), and cyclin-dependent kinase inhibitors (CKIs) in different bone cell populations in order to define the potential mechanisms of c-Fos transformation. Immunohistochemical analysis in embryonic and early postnatal bone demonstrated that cyclin E and its kinase partner CDK2 were expressed specifically in bone-forming osteoblasts. Cyclin D1 expression was absent despite high levels of CDK4 and CDK6, and the CKI p27 was expressed in chondrocytes, osteoclasts, and at lower levels in osteoblasts. Following activation of the c-fos transgene in vivo and before overt tumor formation, cyclin D1 expression increased dramatically and was colocalized with exogenous c-Fos protein specifically in osteoblasts and chondrocytes, but not in osteoclasts. Prolonged activation of c-Fos resulted in osteosarcoma formation wherein the levels of cyclin D1, cyclin E, and CDKs 2, 4, and 6 were high in a wide spectrum of malignant cell types, especially in transformed osteoblasts. The CKI p27 was expressed at very high levels in bone-resorbing osteoclasts, and to a lesser extent in chondrocytes and osteoblasts. These in vivo observations suggest that cyclin D1 may be a target for c-Fos action and that elevation of cyclin D1 in osteoblasts which already express cyclin E/CDK2 and the cyclin D1 partners CDKs-4 and 6, may predispose cells to uncontrolled cell growth leading to osteosarcoma development. This study implicates altered cell cycle control as a potential mechanism through which c-Fos causes osteoblast transformation and bone tumor formation.

Cyclin D1 overexpression correlates with poor prognosis in patients with tongue squamous cell carcinoma

Tongue squamous cell carcinoma makes up a large percentage of head and neck cancers, and the incidence among young patients is increasing. The aim of this study was to reveal the correlation between cyclin D1 (CCND1) expression and clinical and histologic features. We performed an immunohistochemical study on the level of CCND1 expression in tumor specimens obtained from 94 patients with tongue squamous cell carcinoma. The relationship between the expression and the following features such as age, sex, smoking and alcohol intake history, T, N, histologic grade, and multiple primary cancer was analyzed. Eighteen patients (19%) showed CCND1 overexpression (tumor cell nuclei positivity >/=50%). The 5-year survival rate of high CCND1 expressors was 39%, which was significantly poor (p=0.04). N classification correlated with CCND1 expression. CCND1 overexpression is associated with poor survival associated with progression of lymph node spread in patients with tongue squamous cell carcinomas. CCND1 expression may be a useful biologic marker for prognosis.

Molecular biology of esophageal squamous cell carcinoma

Esophageal squamous cell carcinoma (ESCC) is the predominant histologic subtype of esophageal cancer and characterized by high mortality rate and geographic differences in incidence. With the advances in the field of molecular biology, our understanding of the pathogenesis, epidemiology and behavior of ESCC continues to evolve. The recent development includes research in etiopathogenesis (viruses and cancer susceptibility genes), keratins, tumor related genes (oncogenes, tumor suppressor genes, genes involved in metastasis and apoptosis genes), proliferation-related factors (nuclear proteins, flow cytometry/morphometry, argyrophilic nucleolar organizer region) and factors related to metastases (cell adhesion molecules and enzymes related to degradation of extracellular matrix). There are ranges of molecular techniques potentially available to complement the traditional approaches in the management of ESCC. On the other hand, critics are needed in the interpretation and translation of these research findings from laboratories to clinics. Further investigations, education and collaborations between the various scientific and clinical disciplines are important to successful application of these molecular findings aiming at improving management of patients with ESCC.

Strategies for molecular intervention in esophageal cancers and their precursor lesions

Molecular analysis of malignant transformation in Barrett's epithelium provides insight into the temporal nature and significance of individual genetic events during multistep esophageal carcinogenesis. Potential targets for intervention in esophageal neoplasms include mutations involving retinoblastoma (Rb) and p53 tumor-suppressor pathways as well as tyrosine kinase cascades, which are known to promote cell cycle progression. Data from recent experiments provide the preclinical rationale for novel pharmacologic interventions in established esophageal cancers, and suggest strategies for chemoprevention in patients at risk for the development of these neoplasms.

Prognostic significance of biologic factors in squamous cell carcinoma of the esophagus

BACKGROUND

Esophageal carcinoma is one of the most lethal tumors. Therefore, it is important to identify prognostic factors for patients with this disease. The objective of this study was to clarify the relation between clinicopathologic and biologic factors in esophageal carcinoma and to determine the prognostic significance of different biologic factors.

METHODS

DNA ploidy pattern, Ki-67 labeling index (LI), and cyclin D1 and p53 protein expression were examined and detailed pathologic examinations were conducted on tumors from 53 patients (46 males and 7 females with a mean age of 66 years [range, 47-85 years]) with surgically resected esophageal squamous cell carcinoma and the prognostic value of these factors was evaluated.

RESULTS

Of the 53 esophagus carcinomas examined, 26 (49%) were classified as DNA diploid. The mean Ki-67 LI was 45 +/- 4. 9% (range, 10.5-86.1%). p53 expression was detected in 38 of the carcinomas (71.7%) and cyclin D1 expression was detected in 35 (66%). Various prognostic factors were examined using the Cox stepwise regression model, four of which were found to correlate with overall survival: tumor size (P = 0.0346), lymph node status (P = 0.0384), Ki-67 LI (P = 0.0161), and p53 expression (P = 0.001). Lower Ki-67 LI and a lower rate of p53 expression were detected in the long term survival group (> 3 years) compared with the short term survival group (P = 0.00045 and P = 0.0023, respectively).

CONCLUSIONS

The biologic factors of Ki-67 LI and p53 expression, as well as clinicopathologic factors, may be used as independent prognostic factors for patients with esophageal carcinoma. However, the results of the current study do not support cyclin D1 expression as a prognostic factor.