Elise D Bowman

National Cancer Institute (USA), Maryland, United States

Are you Elise D Bowman?

Claim your profile

Publications (88)557.93 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Global changes in gene expression accompany the development of cancer. Thus, inherited variants in microRNA binding sites are likely candidates for conferring inherited susceptibility. Using an in-silico approach, we compiled a comprehensive list of SNPs predicted to modulate microRNA binding in genes from several key lung cancer pathways. We then investigated whether these SNPs were associated with lung cancer risk in two independent populations. In general, SNPs in microRNA binding sites are rare. However, some allelic variation was observed. We found that rs1126579 in CXCR2 was associated with a reduced risk of lung cancer in both European American (ORTT vs. CC 0.56 [0.37 - 0.88]; P=0.008) and Japanese (ORTT vs. CC 0.62 [0.38 - 1.00]; P=0.049) populations. Further, we found that the SNP disrupted a novel binding site for miR-516a-3p, led to a moderate increase in CXCR2 mRNA and protein expression and increased MAPK signaling. Moreover, analysis of rs1126579 with serum levels of IL-8, its endogenous ligand, supported an interaction whereby rs1126579-T and high serum IL-8 conferred synergistic protection from lung cancer. Our findings demonstrate a function for a 3'UTR SNP in modulating CXCR2 expression, signaling and susceptibility to lung cancer. Copyright © 2014, American Association for Cancer Research.
    Cancer research. 12/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Lung cancer has a familial component which suggests a genetic contribution to its etiology. Given the strong evidence linking smoking with lung cancer, we studied miRNA-related loci in genes associated with smoking behavior. CHRNA, CHRNB gene families, CYP2A6 and DRD1 were mined for single nucleotide polymorphisms (SNPs) that fell within the seed region of miRNA binding sites and then tested for associations with risk in a three-stage validation approach. A 3'UTR SNP in DRD1 (Dopamine Receptor D1) was associated with a lower risk of lung cancer among individuals exposed to secondhand smoke during childhood (OR: 0.69; 0.60, 0.79; P<0.0001). This relationship was evident in both ever (OR: 0.74; 0.62, 0.88; P=0.001) and never smokers (OR 0.61; 0.47, 0.79; P<0.0001), European American (OR: 0.65; 0.53, 0.80; P<0.0001) and African American (OR: 0.73; 0.62, 0.88; P=0.001) populations. While much remains undefined about the long-term risks associated with exposure to secondhand smoke and heterogeneity between individuals in regard to their susceptibility to the effects of secondhand smoke, our data show an interaction between a SNP in the 3'UTR of DRD1 and exposure to secondhand smoke during childhood. Further work is needed to explore the mechanistic underpinnings of this SNP and the nature of the interaction between DRD1 and exposure to secondhand smoke during childhood.
    Cancer prevention research (Philadelphia, Pa.). 10/2014;
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Lung cancer remains the most common cause of cancer deaths worldwide, yet there is currently a lack of diagnostic noninvasive biomarkers that could guide treatment decisions. Small molecules (<1500 Da) were measured in urine collected from 469 lung cancer patients and 536 population controls using unbiased liquid chromatography-mass spectrometry. Clinical putative diagnostic and prognostic biomarkers were validated by quantitation and normalized to creatinine levels at two different time points and further validated in an independent sample set, which comprises 80 cases and 78 population controls, with similar demographic and clinical characteristics when compared to the training set. Creatine riboside (IUPAC name: 2-{2-[(2R,3R,4S,5R)-3,4-dihydroxy-5-(hydroxymethyl)-oxolan-2-yl]-1-methylcarbamimidamido}acetic acid), a novel molecule identified in this study, and N-acetylneuraminic acid (NANA), were each significantly (P <0.00001) elevated in non-small cell lung cancer (NSCLC) and associated with worse prognosis (hazard ratio (HR) =1.81 [P =0.0002], and 1.54 [P =0.025], respectively). Creatine riboside was the strongest classifier of lung cancer status in all and stage I-II cases, important for early detection, and also associated with worse prognosis in stage I-II lung cancer (HR =1.71, P =0.048). All measurements were highly reproducible with intraclass correlation coefficients ranging from 0.82 - 0.99. Both metabolites were significantly (P <0.03) enriched in tumor tissue compared to adjacent non-tumor tissue (N =48), thus revealing their direct association with tumor metabolism. Creatine riboside and NANA may be robust urinary clinical metabolomic markers that are elevated in tumor tissue and associated with early lung cancer diagnosis and worse prognosis.
    Cancer Research 04/2014; · 9.28 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: There are no robust noninvasive methods for colorectal cancer screening and diagnosis. Metabolomic and gene expression analyses of urine and tissue samples from mice and humans were used to identify markers of colorectal carcinogenesis. Mass spectrometry-based metabolomic analyses of urine and tissues from wild-type C57BL/6J and Apc(Min/+) mice, as well as from mice with azoxymethane-induced tumors, was employed in tandem with gene expression analysis. Metabolomics profiles were also determined on colon tumor and adjacent non-tumor tissues from 39 patients. The effects of β-catenin activity on metabolic profiles were assessed in mice with colon-specific disruption of Apc. Thirteen markers were found in urine associated with development of colorectal tumors in Apc(Min/+) mice. Metabolites related to polyamine metabolism, nucleic acid metabolism, and methylation, identified tumor-bearing mice with 100% accuracy, and also accurately identified mice with polyps. Changes in gene expression in tumor samples from mice reflected the observed changes in metabolic products detected in urine; similar changes were observed in mice with azoxymethane-induced tumors and mice with colon-specific activation of β-catenin. The metabolic alterations indicated by markers in urine therefore appear to occur during early stages of tumorigenesis, when cancer cells are proliferating. In tissues from patients, tumors had stage-dependent increases in 12 metabolites associated with the same metabolic pathways identified in mice (including amino acid metabolism and polyamine metabolism). Ten metabolites that were increased in tumor tissues, compared with non-tumor tissues (proline, threonine, glutamic acid, arginine, N1-acetylspermidine, xanthine, uracil, betaine, symmetric dimethylarginine, and asymmetric-dimethylarginine), were also increased in urine from tumor-bearing mice. Gene expression and metabolomic profiles of urine and tissue samples from mice with colorectal tumors and of colorectal tumor samples from patients revealed metabolites associated with specific metabolic changes that are indicative of early-stage tumor development. These urine and tissue markers might be used in early detection of colorectal cancer.
    Gastroenterology 01/2014; · 12.82 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Background and aims Patients with inflammatory bowel disease (IBD) have a higher risk of developing colorectal cancer than the general population. Genome-wide association studies have identified and replicated several loci associated with risk of IBD; however, it is currently unknown whether these loci are also associated with colon cancer risk. Methods We selected 15 validated SNPs associated with risk of either Crohn's disease, ulcerative colitis, or both in previous GWAS and tested whether these loci were also associated with colon cancer risk in a two-stage study design. Results We found that rs744166 in STAT3 was associated with colon cancer risk in two studies; however, the direction of the observation was reversed in TP53 mutant tumors possibly due to a nullification of the effect by mutant p53. The SNP, which lies within intron 1 of the STAT3 gene, was associated with lower expression of STAT3 mRNA in TP53 wild-type, but not mutant, tumors. Conclusions These data suggest that the STAT3 locus is associated with both IBD and cancer. Further understanding the function of this variant in relation to TP53 could possibly explain the role of this gene in autoimmunity and cancer. Furthermore, an analysis of this locus, specifically in a population with IBD, could help to resolve the relationship between this SNP and cancer.
    Cancer Epidemiology. 01/2014;
  • [Show abstract] [Hide abstract]
    ABSTRACT: Colon cancer (CC) is a leading cause of cancer mortality. Novel biomarkers are needed to identify CC patients at high risk of recurrence and those who may benefit from therapeutic intervention. The aim of this study is to investigate if miR-21 expression from RNA isolated from formalin-fixed paraffin-embedded (FFPE) tissue sections is associated with prognosis and therapeutic outcome for patients with CC. The expression of miR-21 was measured by quantitative reverse transcriptase-polymerase chain reaction in a Japanese cohort (stage I-IV, n = 156) and a German cohort (stage II, n = 145). High miR-21 expression in tumors was associated with poor survival in both the stage II/III Japanese (P = 0.0008) and stage II German (P = 0.047) cohorts. These associations were independent of other clinical covariates in multivariable models. Receipt of adjuvant chemotherapy was not beneficial in patients with high miR-21 in either cohort. In the Japanese cohort, high miR-21 expression was significantly associated with poor therapeutic outcome (P = 0.0001) and adjuvant therapy was associated with improved survival in patients with low miR-21 (P = 0.001). These results suggest that miR-21 is a promising biomarker to identify patients with poor prognosis and can be accurately measured in FFPE tissues. The expression of miR-21 may also identify patients who will benefit from adjuvant chemotherapy. © 2013 Wiley Periodicals, Inc.
    International Journal of Cancer 10/2013; · 6.20 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Prognostic tests for early stage lung cancer patients may provide needed guidance on postoperative surveillance and therapeutic decisions. We used a novel strategy to develop and validate a prognostic classifier for early stage lung cancer. Specifically, we focused on 42 genes with roles in lung cancer or cancer prognosis. Expression of these biologically relevant genes and their association with relapse-free survival were evaluated using microarray data from 148 stage I lung adenocarcinoma patients. Seven genes associated with relapse-free survival were further examined by quantitative RT-PCR in 291 lung adenocarcinoma tissues from Japan, the United States and Norway. Only BRCA1, HIF1A, DLC1, and XPO1 were each significantly associated with prognosis in the Japan and US/Norway cohorts. A Cox regression-based classifier was developed using these four genes on the Japan cohort and validated in stage I lung adenocarcinoma from the US/Norway cohort and three publically available lung adenocarcinoma expression profiling datasets. The results suggests that the classifier is robust across ethnically and geographically diverse populations regardless of the technology used to measure gene expression. We evaluated the combination of the four-gene classifier with microRNA miR-21 (MIR21) expression and found that the combination improved associations with prognosis, which were significant in stratified analyses on stage IA and stage IB patients. Thus, the four coding gene classifier, alone or with miR-21 expression, may provide a clinically useful tool to identify high risk patients and guide recommendations regarding adjuvant therapy and postoperative surveillance of stage I lung adenocarcinoma patients.
    Cancer Research 05/2013; · 9.28 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Through their roles in tissue remodeling, variants in the genes that encode alpha1-antitrypsin (AAT) and neutrophil elastase (NE) were hypothesized to be associated with the risk of both chronic obstructive pulmonary disease (COPD) and non-small cell lung cancer (NSCLC). Cases with prevalent COPD (n=145), incident NSCLC (n=203) or prevalent COPD plus NSCLC (n=118) were compared to disease-free controls (n=317), to assess two functional polymorphisms in serpin peptidase inhibitor, clade A, member 1 (SERPINA1), which encodes AAT, and eleven tagging polymorphisms in and around elastase 2 (ELA2), which encodes NE. All analyses were stratified by race. Among African-Americans, the less efficient SERPINA1 variant appeared to be associated with increased risk of prevalent COPD but only in the presence of NSCLC (odds ratio=7.39; 95% confidence interval=1.03-53.21) and not after correcting for multiple comparisons. Variations in SERPINA1 and ELA2 were not consistently or strongly associated with the risk of either COPD or NSCLC in either race.
    Anticancer research 09/2012; 32(9):3923-8. · 1.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The primary risk factor for chronic obstructive pulmonary disease (COPD) and non-small cell lung cancer (NSCLC) is cigarette smoking but shared susceptibility factors, such as variations in the matrix metalloproteinase-1 (MMP1) gene, may also underlie both diseases. Cases with prevalent COPD (n=167), incident NSCLC (n=242), or prevalent COPD plus incident NSCLC (n=128) were compared to disease-free controls (n=338) to assess six MMP1 polymorphisms. The association between these polymorphisms and survival in NSCLC was also evaluated. Rs11292517 among African-Americans [odds ratio (OR)=5.48, 95% confidence interval (CI)=1.17-25.72] and rs2071230 among Caucasians (OR=2.51, 95% CI=1.09-5.77) appeared to be associated with NSCLC risk in the presence of COPD. Rs470558 appeared to be associated with survival in NSCLC among African-Americans (hazard ratio=3.94; 95%CI=1.14-13.63). No associations remained after adjusting for multiple comparisons. Polymorphisms in MMP1 were not consistently associated with prevalent COPD or incident NSCLC nor with survival in NSCLC.
    Anticancer research 09/2012; 32(9):3917-22. · 1.71 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Conflicting reports exist regarding the contribution of SNP309 in MDM2 to cancer risk. Recently, SNP285 was shown to act as an antagonist to SNP309 by overriding the effect of SNP309 on SP1-mediated transcription. Moreover, SNP285 modified the relationship between SNP309 and risk of breast, ovarian and endometrial cancer. We assessed whether SNP285 confounded the effect of SNP309 in lung cancer in a cohort of 720 controls and 556 cases. Our cohort included both Caucasians and African Americans. Neither SNP309 nor SNP285 was associated with lung cancer risk or survival. In addition, removal of individuals who carried the variant C allele of SNP285 did not modify the association between SNP309 with either lung cancer risk or survival. Although an effect of SNP285 has been demonstrated in breast, ovarian and endometrial cancer, our findings do not support a role for this SNP in lung cancer and raise the possibility that the effect of SNP285 is restricted to cancers in women.
    International Journal of Cancer 04/2012; 131(11):2710-6. · 6.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Because chronic intestinal inflammation is a risk factor for colorectal cancer, we hypothesized that genetic variants of inflammatory mediators, such as mannose-binding lectin 2 (MBL2), are associated with colon cancer susceptibility. Here, we report the association of 24 MBL2 single-nucleotide polymorphisms (SNP) and corresponding haplotypes with colon cancer risk in a case-control study. Four SNPs in the 3'-untranslated region (UTR) of the gene (rs10082466, rs2120132, rs2099902, and rs10450310) were associated with an increased risk of colon cancer in African Americans. ORs for homozygous variants versus wild-type ranged from 3.17 [95% confidence interval (CI), 1.57-6.40] to 4.51 (95% CI, 1.94-10.50), whereas the 3'-UTR region haplotype consisting of these four variants had an OR of 2.10 (95% CI, 1.42-3.12). The C allele of rs10082466 exhibited a binding affinity of miR-27a and this allele was associated with both lower MBL plasma levels and activity. We found that 5' secretor haplotypes known to correlate with moderate and low MBL serum levels exhibited associations with increased risk of colon cancer in African Americans, specifically as driven by two haplotypes, LYPA and LYQC, relative to the referent HYPA haplotype (LYPA: OR, 2.60; 95% CI, 1.33-5.08 and LYQC: OR, 2.28; 95% CI, 1.20-4.30). Similar associations were not observed in Caucasians. Together, our results support the hypothesis that genetic variations in MBL2 increase colon cancer susceptibility in African Americans.
    Cancer Research 02/2012; 72(6):1467-77. · 9.28 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Colorectal cancer is the third most incident cancer and cause of cancer-related death in the United States. MicroRNAs, a class of small non-coding RNAs, have been implicated in the pathogenesis and prognosis of colorectal cancer, although few studies have examined the relationship between germline mutation in the microRNAs with risk and prognosis. We therefore investigated the association between a SNP in hsa-mir-608, which lies within the 10q24 locus, and colorectal cancer. A cohort consisting of 245 cases and 446 controls was genotyped for rs4919510. The frequency of the GG genotype was significantly higher in African Americans (15%) compared to Caucasians (3%) controls. There was no significant association between rs4919510 and colorectal cancer risk (African American: OR(GG vs. CC) 0.89 [95% CI, 0.41-1.80]) (Caucasian: OR(GG vs. CC) 1.76, ([95% CI, 0.48-6.39]). However, we did observe an association with survival. The GG genotype was associated with an increased risk of death in Caucasians (HR(GG vs. CC) 3.54 ([95% CI, 1.38-9.12]) and with a reduced risk of death in African Americans (HR(GG vs. CC) 0.36 ([95% CI 0.12-1.07). These results suggest that rs4910510 may be associated with colorectal cancer survival in a manner that is dependent on race.
    PLoS ONE 01/2012; 7(5):e36306. · 3.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cellular senescence can be a functional barrier to carcinogenesis. We hypothesized that inflammation modulates carcinogenesis through senescence and DNA damage response (DDR). We examined the association between senescence and DDR with macrophage levels in inflammatory bowel disease (IBD). In vitro experiments tested the ability of macrophages to induce senescence in primary cells. Inflammation modulating microRNAs were identified in senescence colon tissue for further investigation. Quantitative immunohistochemistry identified protein expression by colon cell type. Increased cellular senescence (HP1γ; P = 0.01) or DDR (γH2A.X; P = 0.031, phospho-Chk2, P = 0.014) was associated with high macrophage infiltration in UC. Co-culture with macrophages (ANA-1) induced senescence in >80% of primary cells (fibroblasts MRC5, WI38), illustrating that macrophages induce senescence. Interestingly, macrophage-induced senescence was partly dependent on nitric oxide synthase, and clinically relevant NO• levels alone induced senescence. NO• induced DDR in vitro, as detected by immunofluorescence. In contrast to UC, we noted in Crohn's disease (CD) that senescence (HP1γ; P<0.001) and DDR (γH2A.X; P<0.05, phospho-Chk2; P<0.001) were higher, and macrophages were not associated with senescence. We hypothesize that nitric oxide may modulate senescence in CD; epithelial cells of CD had higher levels of NOS2 expression than in UC (P = 0.001). Microarrays and quantitative-PCR identified miR-21 expression associated with macrophage infiltration and NOS2 expression. Senescence was observed in IBD with senescence-associated β-galactosidase and HP1γ. Macrophages were associated with senescence and DDR in UC, and in vitro experiments with primary human cells showed that macrophages induce senescence, partly through NO•, and that NO• can induce DDR associated with senescence. Future experiments will investigate the role of NO• and miR-21 in senescence. This is the first study to implicate macrophages and nitrosative stress in a direct effect on senescence and DDR, which is relevant to many diseases of inflammation, cancer, and aging.
    PLoS ONE 01/2012; 7(9):e44156. · 3.53 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Previous studies that were based primarily on small numbers of patients suggested that certain circulating proinflammatory cytokines may be associated with lung cancer; however, large independent studies are lacking. Associations between serum interleukin 6 (IL-6) and interleukin 8 (IL-8) levels and lung cancer were analyzed among 270 case patients and 296 control subjects participating in the National Cancer Institute-Maryland (NCI-MD) case-control study. Results were validated in 532 case patients and 595 control subjects in a nested case-control study within the prospective Prostate, Lung, Colorectal, and Ovarian (PLCO) Cancer Screening Trial. Association with C-reactive protein (CRP), a systemic inflammation biomarker, was also analyzed. Associations between biomarkers and lung cancer were estimated using logistic regression models adjusted for smoking, stage, histology, age, and sex. The 10-year standardized absolute risks of lung cancer were estimated using a weighted Cox regression model. Serum IL-6 and IL-8 levels in the highest quartile were associated with lung cancer in the NCI-MD study (IL-6, odds ratio [OR] = 3.29, 95% confidence interval [CI] = 1.88 to 5.77; IL-8, OR = 2.06, 95% CI = 1.19 to 3.57) and with lung cancer risk in the PLCO study (IL-6, OR = 1.48, 95% CI = 1.04 to 2.10; IL-8, OR = 1.57, 95% CI = 1.10 to 2.24), compared with the lowest quartile. In the PLCO study, increased IL-6 levels were only associated with lung cancer diagnosed within 2 years of blood collection, whereas increased IL-8 levels were associated with lung cancer diagnosed more than 2 years after blood collection (OR = 1.57, 95% CI = 1.15 to 2.13). The 10-year standardized absolute risks of lung cancer in the PLCO study were highest among current smokers with high IL-8 and CRP levels (absolute risk = 8.01%, 95% CI = 5.77% to 11.05%). Although increased levels of both serum IL-6 and IL-8 are associated with lung cancer, only IL-8 levels are associated with lung cancer risk several years before diagnosis. Combination of IL-8 and CRP are more robust biomarkers than either marker alone in predicting subsequent lung cancer.
    CancerSpectrum Knowledge Environment 06/2011; 103(14):1112-22. · 14.07 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Selective activation of p53 target genes in response to various cellular stresses is a critical step in determining the ability to induce cell-cycle arrest or apoptosis. Here we report the identification of the microRNA miR-22 as a p53 target gene that selectively determines the induction of p53-dependent apoptosis by repressing p21. Combinatorial analyses of the AGO2 immunocomplex and gene expression profiles identified p21 as a direct target of miR-22. Induction of p21 was inhibited by miR-22 after exposure to the genotoxic agent Adriamycin (doxorubicin; Bedford Laboratories), sensitizing cells to p53-dependent apoptosis. Interestingly, the activation of miR-22 depended on the intensity of the stresses that induced cells to undergo apoptosis in the presence of p21 suppression. Our findings define an intrinsic molecular switch that determines p53-dependent cellular fate through post-transcriptional regulation of p21.
    Cancer Research 05/2011; 71(13):4628-39. · 9.28 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Circulating micro-RNA (miR) profiles have been proposed as promising diagnostic and prognostic biomarkers for cancer, including lung cancer. We have developed methods to accurately and reproducibly measure micro-RNA levels in serum and plasma. Here, we study paired serum and plasma samples from 220 patients with early stage nonsmall cell lung cancer (NSCLC) and 220 matched controls. We use qRT-PCR to measure the circulating levels of 30 different miRs that have previously been reported to be differently expressed in lung cancer tissue. Duplicate RNA extractions were performed for 10% of all samples, and micro-RNA measurements were highly correlated among those duplicates. This demonstrates high reproducibility of our assay. The expressions of miR-146b, miR-221, let-7a, miR-155, miR-17-5p, miR-27a and miR-106a were significantly reduced in the serum of NSCLC cases, while miR-29c was significantly increased. No significant differences were observed in plasma of patients compared with controls. Overall, expression levels in serum did not correlate well with levels in plasma. In secondary analyses, reduced plasma expression of let-7b was modestly associated with worse cancer-specific mortality in all patients, and reduced serum expression of miR-223 was modestly associated with cancer-specific mortality in stage IA/B patients. MiR profiles also showed considerable differences comparing African American and European Americans. In summary, we found significant differences in miR expression when comparing cases and controls and find evidence that expression of let-7b is associated with prognosis in NSCLC.
    International Journal of Cancer 05/2011; 130(6):1378-86. · 6.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: LKB1/STK11 is a tumor suppressor and a negative regulator of mammalian target of rapamycin signaling. It is inactivated in 30% of lung cancer cell lines but only 5-15% of primary lung adenocarcinomas. There is evidence that homozygous deletion (HD) of chromosome 19p at the LKB locus contributes to the inactivation of the gene in primary human lung cancers. Here, we used several complementary genetic approaches to assess the LKB1 locus in primary non-small cell lung cancers (NSCLCs). We first analyzed 124 NSCLC cases for allelic imbalance using eight microsatellite markers on chromosome 19p, which revealed an overall rate of 65% (80 of 124) loss of heterozygosity (LOH). We next used chromogenic in situ hybridization (CISH) to directly examine the chromosomal status of the LKB1 locus. In all, 65 of 124 LOH tested samples were available for CISH and 58 of those (89%) showed either loss of one copy of chromosome 19p (LOH, 40 of 65 cases, 62%) or both copies (HD 18 of 65 cases, 28%). The occurrence of HD was significantly more frequent in Caucasian (35%) than in African-American patients (6%) (P=0.04). A total of 62 of 124 samples with LOH at one or both markers immediately flanking the LKB1 gene were further analyzed by directly sequencing the complete coding region, which identified 7 of 62 (11%) tumors with somatic mutations in the gene. Jointly, our data identified total inactivation of the LKB1 gene by either HD or LOH with somatic mutation in 39% of tested samples, whereas loss of chromosome 19p region by HD or LOH at the LKB1 region occured in 90% of NSCLC.
    Oncogene 05/2011; 30(35):3784-91. · 8.56 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Although exposure to estrogen may directly influence or modify the association between cigarette smoking and lung cancer risk, results from epidemiologic studies examining the association between reproductive and hormonal factors and risk of lung cancer among women have been inconsistent. Between 1998 and 2008, 430 women diagnosed with nonsmall cell lung cancer, 316 hospital controls and 295 population controls were recruited into the multi-center Maryland Lung Cancer Study. Conditional logistic regression was used to estimate odds ratios (ORs) and 95% confidence intervals (CIs) according to reproductive and hormonal exposures adjusting for age, smoking, passive smoking, education and household income. Results were similar for hospital and population based controls, so the control groups were combined. Reduced risks of lung cancer were observed among women with greater parity (≥ 5 vs. 1-2 births: OR = 0.50, 95% CI = 0.32, 0.78, p-trend = 0.002) and later ages at last birth (≥ 30 vs. <25 years old: OR = 0.68, 95% CI = 0.48, 0.98, p-trend = 0.04). After mutual adjustment parity, but not age at last birth, remained significantly inversely associated with risk (p-trend = 0.01). No associations were found for nonsmall cell lung cancer risk with age at menarche, age at first birth, menopausal status, oral contraceptive use or menopausal hormone use, including use of oral estrogens. Compatible with findings from recent epidemiologic studies, we observed a reduction in the risk of nonsmall cell lung cancer with increasing number of births. Other reproductive and hormonal exposures, including menopausal hormone therapy use, were not associated with risk.
    International Journal of Cancer 03/2011; 128(6):1404-13. · 6.20 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: There is increasing evidence that altered microRNA expression is associated with tumor progression and survival in cancer patients. We tested if the expression of specific microRNAs was associated with prognosis and disease progression in early-stage lung adenocarcinoma. The expression of miR-21, miR-17, and miR-155 was measured by quantitative RT-PCR in tissues from 317 non-small cell lung cancer (NSCLC) patients that originated from Maryland, Norway, and Japan. Kaplan-Meier and Cox regression analysis evaluated associations of microRNA expression with cancer-specific mortality and disease-free survival. Elevated miR-21 (HR 2.06, 1.13-3.75), miR-17 (HR 2.00, 1.10-3.61), and miR-155 (HR 2.37, 1.27-4.42) was associated with worse cancer-specific mortality in the Maryland cohort. These were evaluated in two additional cohorts and only miR-21 was associated with worse cancer-specific mortality in the Norwegian cohort (HR 2.78, 1.22-6.31) and worse relapse-free survival in the Japanese cohort (HR 2.82, 1.57-5.07). More advanced stage tumors expressed significantly higher levels of miR-21 compared with TNM stage I tumors. TNM stage I patients were evaluated separately and high levels of miR-21 was associated with worse cancer-specific mortality (HR 2.16, 1.11-4.21) and relapse-free survival (3.40, 1.57-7.36) independent of other clinical factors. This is the first study to report that increased miR-21 expression is associated with disease progression and survival in stage I lung cancer. This suggests that expression of miR-21 may contribute to lung carcinogenesis and serve as a therapeutic target or early-stage prognostic biomarker for lung adenocarcinoma.
    Clinical Cancer Research 02/2011; 17(7):1875-82. · 7.84 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The XPA gene has a commonly occurring polymorphism (G23A) associated with cancer risk. This study assessed the functional significance of this polymorphism, which is localised near the translation start codon. Lymphoblastoid cell lines with alternative homozygous genotypes showed no significant differences in their XPA levels. The luciferase reporter assay detected no functional difference between the two sequences. Unexpectedly, we found that the alternatively spliced form of XPA mRNA lacked a part of exon 1. Only the reading frame downstream of codon Met59 was preserved. The alternative mRNA is expressed in various human tissues. The analysis of the 5'cDNA ends showed similar transcription start sites for the two forms. The in vitro expression of the alternative XPA labelled with the red fluorescent protein (mRFP) showed a lack of preferential nuclear accumulation of the XPA isoform. The biological role of the alternative XPA mRNA form remains to be elucidated.
    Cellular & Molecular Biology Letters 12/2010; 15(4):611-29. · 1.95 Impact Factor

Publication Stats

5k Citations
557.93 Total Impact Points

Institutions

  • 1992–2014
    • National Cancer Institute (USA)
      • • Laboratory of Human Carcinogenesis
      • • Center for Cancer Research
      • • Cancer Etiology Branch (CEB)
      Maryland, United States
    • University of Colorado Hospital
      • Department of Pediatrics
      Denver, Colorado, United States
  • 1990–2013
    • National Institutes of Health
      • • Laboratory of Human Carcinogenesis
      • • Division of Cancer Epidemiology and Genetics
      Maryland, United States
  • 1998–2009
    • Georgetown University
      • Lombardi Cancer Center
      Washington, D. C., DC, United States
  • 2005
    • Uniformed Services University of the Health Sciences
      Maryland, United States
  • 1996–2004
    • University at Buffalo, The State University of New York
      • Department of Social and Preventive Medicine
      Buffalo, NY, United States
  • 2000–2003
    • Roswell Park Cancer Institute
      • • Department of Epidemiology
      • • Department of Cancer Prevention, Epidemiology and Biostatistics
      Buffalo, New York, United States
  • 1997
    • NCI-Frederick
      Maryland, United States
  • 1995
    • University of Idaho
      • Department of Chemistry
      Moscow, ID, United States
  • 1994
    • Johns Hopkins Medicine
      • Department of Environmental Health Sciences
      Baltimore, MD, United States