Cigarette, cigar, and pipe smoking and the risk of head and neck cancers: pooled analysis in the International Head and Neck Cancer Epidemiology Consortium.

Cigar and pipe smoking are considered risk factors for head and neck cancers, but the magnitude of effect estimates for these products has been imprecisely estimated. By using pooled data from the International Head and Neck Cancer Epidemiology (INHANCE) Consortium (comprising 13,935 cases and 18,691 controls in 19 studies from 1981 to 2007), we applied hierarchical logistic regression to more precisely estimate odds ratios and 95% confidence intervals for cigarette, cigar, and pipe smoking separately, compared with reference groups of those who had never smoked each single product. Odds ratios for cigar and pipe smoking were stratified by ever cigarette smoking. We also considered effect estimates of smoking a single product exclusively versus never having smoked any product (reference group). Among never cigarette smokers, the odds ratio for ever cigar smoking was 2.54 (95% confidence interval (CI): 1.93, 3.34), and the odds ratio for ever pipe smoking was 2.08 (95% CI: 1.55, 2.81). These odds ratios increased with increasing frequency and duration of smoking (Ptrend ≤ 0.0001). Odds ratios for cigar and pipe smoking were not elevated among ever cigarette smokers. Head and neck cancer risk was elevated for those who reported exclusive cigar smoking (odds ratio = 3.49, 95% CI: 2.58, 4.73) or exclusive pipe smoking (odds ratio = 3.71, 95% CI: 2.59, 5.33). These results suggest that cigar and pipe smoking are independently associated with increased risk of head and neck cancers.

Gene expression profiling of papillary thyroid carcinoma identifies transcripts correlated with BRAF mutational status and lymph node metastasis.

PURPOSE: To identify papillary thyroid carcinoma (PTC)-associated transcripts, we compared the gene expression profiles of three Serial Analysis of Gene Expression libraries generated from thyroid tumors and a normal thyroid tissue. EXPERIMENTAL DESIGN: Selected transcripts were validated in a panel of 57 thyroid tumors using quantitative PCR (qPCR). An independent set of 71 paraffin-embedded sections was used for validation using immunohistochemical analysis. To determine if PTC-associated gene expression could predict lymph node involvement, a separate cohort of 130 primary PTC (54 metastatic and 76 nonmetastatic) was investigated. The BRAF(V600E) mutational status was compared with qPCR data to identify genes that might be regulated by abnormal BRAF/MEK/extracellular signal-regulated kinase signaling. RESULTS: We identified and validated new PTC-associated transcripts. Three genes (CST6, CXCL14, and DHRS3) are strongly associated with PTC. Immunohistochemical analysis of CXCL14 confirmed the qPCR data and showed protein expression in PTC epithelial cells. We also observed that CST6, CXCL14, DHRS3, and SPP1 were associated with PTC lymph node metastasis, with CST6, CXCL14, and SPP1 being positively correlated with metastasis and DHRS3 being negatively correlated. Finally, we found a strong correlation between CST6 and CXCL14 expression and BRAF(V600E) mutational status, suggesting that these genes may be induced subsequently to BRAF activation and therefore may be downstream in the BRAF/MEK/extracellular signal-regulated kinase signaling pathway. CONCLUSION: CST6, CXCL14, DHRS3, and SPP1 may play a role in PTC pathogenesis and progression and are possible molecular targets for PTC therapy.

Molecular profiling of matched samples identifies biomarkers of papillary thyroid carcinoma lymph node metastasis.

Biomarkers of papillary thyroid carcinoma (PTC) metastasis can accurately identify metastatic cells and aggressive tumor behavior. To find new markers, serial analysis of gene expression (SAGE) was done on three samples from the same patient: normal thyroid tissue, primary PTC, and a PTC lymph node metastasis. This genomewide expression analysis identified 31 genes expressed in lymph node metastasis, but not in the primary tumor. Eleven genes were evaluated by quantitative real-time reverse transcription-PCR (qPCR) on independent sets of matched samples to find genes that were consistently different between the tumor and metastatic samples. LIMD2 and PTPRC (CD45) showed a statistically significant difference in expression between tumor and metastatic samples (P < 0.0045), and an additional gene (LTB) had borderline significance. PTPRC and LTB were tested by immunohistochemistry in an independent set of paired samples, with both markers showing a difference in protein expression. All 20 metastases from 6 patients showed expression in both markers, with little or no expression in primary tumor. Some of these markers could provide an improved means to detect metastatic PTC cells during initial staging of a newly diagnosed carcinoma and/or to rule out recurrence. The functional role of these genes may also provide insight into mechanisms of thyroid cancer metastasis.

Significant differences in demographic, clinical, and pathological features in relation to smoking and alcohol consumption among 1,633 head and neck cancer patients.

OBJECTIVE: As a lifestyle-related disease, social and cultural disparities may influence the features of squamous cell carcinoma of the head and neck in different geographic regions. We describe demographic, clinical, and pathological aspects of squamous cell carcinoma of the head and neck according to the smoking and alcohol consumption habits of patients in a Brazilian cohort. METHODS: We prospectively analyzed the smoking and alcohol consumption habits of 1,633 patients enrolled in five São Paulo hospitals that participated in the Brazilian Head and Neck Genome Project - Gencapo. RESULTS: The patients who smoked and drank were younger, and those who smoked were leaner than the other patients, regardless of alcohol consumption. The non-smokers/non-drinkers were typically elderly white females who had more differentiated oral cavity cancers and fewer first-degree relatives who smoked. The patients who drank presented significantly more frequent nodal metastasis, and those who smoked presented less-differentiated tumors. CONCLUSIONS: The patients with squamous cell carcinoma of the head and neck demonstrated demographic, clinical, and pathological features that were markedly different according to their smoking and drinking habits. A subset of elderly females who had oral cavity cancer and had never smoked or consumed alcohol was notable. Alcohol consumption seemed to be related to nodal metastasis, whereas smoking correlated with the degree of differentiation.

Proteomic approaches identify members of cofilin pathway involved in oral tumorigenesis.

The prediction of tumor behavior for patients with oral carcinomas remains a challenge for clinicians. The presence of lymph node metastasis is the most important prognostic factor but it is limited in predicting local relapse or survival. This highlights the need for identifying biomarkers that may effectively contribute to prediction of recurrence and tumor spread. In this study, we used one- and two-dimensional gel electrophoresis, mass spectrometry and immunodetection methods to analyze protein expression in oral squamous cell carcinomas. Using a refinement for classifying oral carcinomas in regard to prognosis, we analyzed small but lymph node metastasis-positive versus large, lymph node metastasis-negative tumors in order to contribute to the molecular characterization of subgroups with risk of dissemination. Specific protein patterns favoring metastasis were observed in the "more-aggressive" group defined by the present study. This group displayed upregulation of proteins involved in migration, adhesion, angiogenesis, cell cycle regulation, anti-apoptosis and epithelial to mesenchymal transition, whereas the "less-aggressive" group was engaged in keratinocyte differentiation, epidermis development, inflammation and immune response. Besides the identification of several proteins not yet described as deregulated in oral carcinomas, the present study demonstrated for the first time the role of cofilin-1 in modulating cell invasion in oral carcinomas.

PVALB, a new Hürthle adenoma diagnostic marker identified through gene expression.

CONTEXT: A better means to accurately identify malignant thyroid nodules and to distinguish them from benign tumors is needed. We previously identified markers for detecting thyroid malignancy, with sensitivity estimated at or close to 100%. One lingering problem with these markers was that false positives occurred with Hürthle cell adenomas (HCA) which lowered test specificity. METHODS: To locate accurate diagnostic markers, we profiled in depth the transcripts of a HCA and a Hürthle cell carcinoma (HCC). From 1146 differentially expressed genes, 18 transcripts specifically expressed in HCA were tested by quantitative PCR in a wide range of thyroid tumors (n = 76). Sensibility and specificity were calculated using receiver operating characteristic (ROC). Selected markers were further validated in an independent set of thyroid tumors (n = 82) by immunohistochemistry. To define the panel that would yield best diagnostic accuracy, these markers were tested in combination with our previous identified markers. RESULTS: Seventeen of the 18 genes showed statistical significance based on a mean relative level of expression (P < 0.05). KLK1 (sensitivity = 0.97) and PVALB (sensitivity = 0.94) were the best candidate markers. The combination of PVALB and C1orf24 increased specificity to >97% and maintained sensitivity for detection of carcinoma. CONCLUSION: We identified tumor markers that can be used in combination for a more accurate preoperative diagnosis of thyroid nodules and for postoperative diagnosis of thyroid carcinoma in tumor sections. This improved test would help physicians rapidly focus treatment on true malignancies and avoid unnecessary treatment of benign tumors, simultaneously improving medical care and reducing costs.

Genomics and proteomics approaches to the study of cancer-stroma interactions.

BACKGROUND: The development and progression of cancer depend on its genetic characteristics as well as on the interactions with its microenvironment. Understanding these interactions may contribute to diagnostic and prognostic evaluations and to the development of new cancer therapies. Aiming to investigate potential mechanisms by which the tumor microenvironment might contribute to a cancer phenotype, we evaluated soluble paracrine factors produced by stromal and neoplastic cells which may influence proliferation and gene and protein expression. METHODS: The study was carried out on the epithelial cancer cell line (Hep-2) and fibroblasts isolated from a primary oral cancer. We combined a conditioned-medium technique with subtraction hybridization approach, quantitative PCR and proteomics, in order to evaluate gene and protein expression influenced by soluble paracrine factors produced by stromal and neoplastic cells. RESULTS: We observed that conditioned medium from fibroblast cultures (FCM) inhibited proliferation and induced apoptosis in Hep-2 cells. In neoplastic cells, 41 genes and 5 proteins exhibited changes in expression levels in response to FCM and, in fibroblasts, 17 genes and 2 proteins showed down-regulation in response to conditioned medium from Hep-2 cells (HCM). Nine genes were selected and the expression results of 6 down-regulated genes (ARID4A, CALR, GNB2L1, RNF10, SQSTM1, USP9X) were validated by real time PCR. CONCLUSIONS: A significant and common denominator in the results was the potential induction of signaling changes associated with immune or inflammatory response in the absence of a specific protein.

Global gene expression profiling of oral cavity cancers suggests molecular heterogeneity within anatomic subsites.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is a frequent neoplasm, which is usually aggressive and has unpredictable biological behavior and unfavorable prognosis. The comprehension of the molecular basis of this variability should lead to the development of targeted therapies as well as to improvements in specificity and sensitivity of diagnosis. RESULTS: Samples of primary OSCCs and their corresponding surgical margins were obtained from male patients during surgery and their gene expression profiles were screened using whole-genome microarray technology. Hierarchical clustering and Principal Components Analysis were used for data visualization and One-way Analysis of Variance was used to identify differentially expressed genes. Samples clustered mostly according to disease subsite, suggesting molecular heterogeneity within tumor stages. In order to corroborate our results, two publicly available datasets of microarray experiments were assessed. We found significant molecular differences between OSCC anatomic subsites concerning groups of genes presently or potentially important for drug development, including mRNA processing, cytoskeleton organization and biogenesis, metabolic process, cell cycle and apoptosis. CONCLUSION: Our results corroborate literature data on molecular heterogeneity of OSCCs. Differences between disease subsites and among samples belonging to the same TNM class highlight the importance of gene expression-based classification and challenge the development of targeted therapies.

Skip metastases in medullary thyroid carcinoma: a single-center experience.

PURPOSE: Total thyroidectomy (TT) with level VI and VII central neck dissection is the initial treatment for medullary thyroid carcinoma (MTC) without identifiable neck metastasis. Level II to V lateral neck dissection is performed if neck metastasis is present or suspected. We conducted this study to identify the frequency and clinical determinants of skip neck metastasis in MTC. METHODS: We reviewed the medical records of 32 patients who underwent TT and bilateral neck dissection for MTC. The clinical features were correlated with pN status in the central versus lateral compartments of the neck. RESULTS: Neck lymph node metastasis (pN+) was found in 20 patients (62.5%) and skip metastases were found in 7 (35%) patients. The sensitivity of the pN status of the central compartment of the neck to predict the pN status of the lateral compartment of the neck was 53.8% and specificity was 63.2%. We found pN+ in 90% of the patients with lymph nodes >15 mm in diameter versus 50% in those with lymph nodes <15 mm in diameter. CONCLUSIONS: There is skip metastasis in MTC. It is unsafe to use the lymph node status of the central compartment of the neck to define the pN status of the lateral neck. A lymph node greater than 15 mm in diameter is related to pN status.