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1.  Genetically Abnormal Circulating Cells in Lung Cancer Patients: An Antigen Independent Fluorescence in-situ Hybridization Based Case-Control Study 
We performed a study to determine if a fluorescence in-situ hybridization (FISH)-based assay using isolated peripheral blood mononuclear cells (PBMCs) with DNA probes targeting specific sites on chromosomes known to have abnormalities in Non Small Cell Lung Cancer (NSCLC) cases could detect circulating genetically abnormal cells (CACs).
Experimental Design
We evaluated 59 NSCLC cases with stage I through IV disease and 24 controls. PBMCs and matched tumors were hybridized with 2 two-color (3p22.1/CEP3 and 10q22.3 [SP-A]/CEP10) and 2 four-color (CEP3, CEP7, CEP17, and 9p21.3 [URO]) and (EGFR, c-MYC, 6p11-q11, and 5p15.2 [LAV]) FISH probes. Percentages of cytogenetically abnormal cells (CACs) in peripheral blood and in matched tumor specimens were quantified using an automated fluorescent scanner. Numbers of CACs were calculated based on the percentage of CACs (defined as PBMCs with genetic abnormalities) per mL of blood and expressed per microliter of blood.
Patients with NSCLC had significantly higher numbers of CACs than did controls. Mean number of CACs ranged from 7.23±1.32/μl for deletions of 10q22.3/CEP10 to 45.52±7.49/μl for deletions of 3p22.1/CEP3. Numbers of CACs with deletions of 3p22.1, 10q22.3, and 9p21.3, and gains of URO, increased significantly from early to advanced stage of disease.
We have developed a sensitive and quantitative antigen-independent FISH-based test for detecting CACs in peripheral blood of patients with NSCLC which showed a significant correlation with the presence of cancer. If this pilot study can be validated in a larger study, CACs may have a role in the management of patients with NSCLC.
PMCID: PMC2949278  PMID: 20651054
2.  A functional variant of tandem repeats in human telomerase gene (hTERT) was associated with survival of patients with early stages of non-small cell lung cancer 
Elevated levels of human telomerase (hTERT) mRNA in tumors is a marker for poorer survival in patients with stage I non-small cell lung cancer (NSCLC). A functional variant of MNS16A-Short tandem repeats in hTERT (S allele) is associated with higher expression levels of hTERT mRNA compared with the MNS16A-long (L) allele. However, it is unknown whether or not the hTERT MNS16A variant genotype predicts survival of NSCLC patients.
Experimental Design
The hTERT genotypes of 808 patients with NSCLC were determined by direct PCR with genomic DNA. Overall median survival times were estimated by the life-table method, and the log-rank test was used to test for homogeneity of the survival curves. Both univariate and multivariate Cox proportional hazards models were used to assess the associations between survival time and the hTERT genotype as well as other known risk factors.
The hTERT variant genotype was not associated with overall survival among the 808 patients. However, among 221 patients with stage I or II NSCLC, the S allele was associated with shorter survival time (P = 0.027, by Log-Rank test). The adjusted hazard ratios (HR) were 1.30 (95% CI = 0.79–2.14, P = 0.310) for the SL-genotype and 2.34 (95% CI = 1.20–4.56, P = 0.012) for the SS-genotype compared with the LL-genotype (P = 0.021 for trend test). These findings were not evident in 587 patients with stage III or IV NSCLC.
The functional MNS16A-SS genotype may be a marker for poorer survival in early stage NSCLC.
PMCID: PMC2905469  PMID: 20466886
NSCLC; VNTR; hTERT; Genotype; Prognosis
3.  Reduced DNA Repair Capacity for Removing Tobacco Carcinogen-Induced DNA Adducts Contributes to Risk of Head and Neck Cancer but not Tumor Characteristics 
Although cigarette smoking and alcohol use are known risk factors for squamous cell carcinoma of head and neck (SCCHN), only a few exposed individuals develop this disease, suggesting an individual susceptibility. In this study, we investigated the associations between genetically determined DNA repair capacity (DRC) for removing tobacco-induced DNA adducts and risk of SCCHN and tumor characteristics.
Experimental Design
We measured DRC in cultured T-lymphocytes using the host-cell reactivation assay in a hospital-based case-control study of 744 SCCHN patients and 753 age-, sex-and ethnicity-matched cancer-free controls recruited from The University of Texas M. D. Anderson Cancer Center.
Patients with SCCHN had significantly lower mean DRC (8.84% ± 2.68%) than controls (9.97% ± 2.61%) (P < 0.0001), and the difference accounted for approximately 2-fold increased risk of SCCHN (adjusted odds ratio [OR], 1.91; 95% CI, 1.52–2.40) after adjustment for other covariates. Compared with the highest DRC quartile of controls, this increased risk was dose-dependent (second highest quartile: OR, 1.40; 95% CI, 0.99–1.98; third quartile: OR, 1.87; 95% CI, 1.34–2.62; and fourth quartile: OR, 2.76; 95% CI, 1.98–3.84, respectively; Ptrend < 0.0001). We also assessed the performance of DRC in risk prediction models by calculating the area of under the receiver operating characteristic curve. The addition of DRC to the model significantly improved the sensitivity of the expanded model. However, we did not find the association between DRC and tumor sites and stages.
DRC is an independent susceptibility biomarker for SCCHN risk but not a tumor marker.
PMCID: PMC2848391  PMID: 20068090
nucleotide excision repair; genetic susceptibility; head and neck neoplasm; molecular epidemiology

Results 1-3 (3)