Abstract Background Ovarian cancer is the fifth most common cause of cancer death in women in the US; approximately 15,000 women will die from this disease in 2011 (ACS, 2011). The 5 year survival rate for stage IV disease is only 18%. Only a handful of independent significant prognostic factors are known, including tumor stage at surgery, size of residual tumor at the end of primary surgery, and age at diagnosis. Understanding how the variation of cytosine methylation in the context of cytosine-guanine dinucleotides (CpGs) affects complex disease etiology and survival is the current focus of many ongoing research studies. We conducted an epigenome-wide study of methylation in ovarian cancer cases to evaluate whether variation in methylation of CpG sites in genomic DNA may be associated with ovarian cancer survival. Methods Subjects included cases from an ongoing case-control study. The Mayo Clinic Ovarian Cancer Study is a clinic-based study that recruits ovarian cancer cases within 12 months of diagnosis. Pre-treatment, germline DNA from lymphocytes from 137 cases was bisulfite-modified, amplified and genotyped on the Illumina 450K methylation chip and included in these analyses. Quality control (QC) analyses include the elimination of all methylation probes with a single nucleotide polymorphism (SNP) or insertion/deletion (in/del) at the same location; removal of non-specific probes; and estimation of bisulfite conversion rates using embedded control probes. Planned analyses include assessment of clinical covariates (age, stage, extent of surgical debulking, grade, presence of ascites) to determine which are associated with overall survival in our data. Additional analyses will assess the age- and multi-variate-adjusted association of each methylation probe with overall survival using Cox proportional hazards regression models with each methylation probe modeled as a continuous variable. Data will be summarized using Manhattan plots. These analyses will be repeated using ‘time to recurrence’ as the outcome variable, with recurrence defined as time to ovarian cancer recurrence/progression or death. Results Bioinformatics analyses suggest that 36,659 probes were located at the site of a SNP or in/del and should be removed from future analyses. Another 448 probes had a detection rate of p< 0.01 and 6630 probes had signals for the negative control samples; all were removed from analyses. A total of 43,802 probes were removed. In addition, ten cases were excluded due to either poor bisulfite conversion (N=9) or extremely low raw methylation values across all probes (N=1). This leaves a total of 127 cases for analyses. Results from planned analyses will be presented, including estimation of the association of methylation probes with both overall survival and time to recurrence. Conclusions Data to be presented will describe whether there is any evidence that methylation of genomic DNA in ovarian cancer cases is associated with outcome of ovarian cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 5008. doi:1538-7445.AM2012-5008
Abstract 893: Associations between HGF, MET, and phospho-MET expression, overall survival, and HGF genotypes in epithelial ovarian cancer
Abstract Background. The hepatocyte growth factor (HGF) signaling pathway regulates key cellular functions related to tumor invasion and metastasis including cell motility, cell proliferation, and morphogenesis. We previously found that minor alleles at a single-nucleotide polymorphism (SNP; rs5745709) in the gene encoding the cytokine HGF was associated with poorer overall survival in women with invasive epithelial ovarian cancer (EOC) enrolled at Mayo Clinic (MAY) and The Cancer Genome Atlas (TCGA) (HR 1.6, 95% CI 1.3-1.9, p=8.9×10−5). In addition, we found that that genotype correlated with HGF expression in ovarian cancer tissue from TCGA women, suggesting that genetically-regulated expression of HGF may play a role in post-diagnosis survival. To further examine this possibility, we evaluated intensity of antibody immunostaining for HGF, MET (HGF's transmembrane tyrosine kinase receptor), and phospho-MET (pMET; MET's activated form) in tumor cells using tissue microarrays (TMAs) created from genotyped primary peritoneal and EOC cases, and correlated these expression levels with overall survival and HGF SNP genotypes. Methods. Participants were 326 white non-Hispanic women over 20 years of age with histologically-confirmed invasive EOC diagnosed between 1998 and 2009. All cases were enrolled at MAY within one year of diagnosis. Five μm sections of TMAs including three 0.6 mm cores per case were immunostained with HGF, MET, and pMET primary antibodies. Staining levels were classified according to combinations of staining extent and intensity as negative (< 10% cells stained), weak, moderate, or strong. The maximal expression value recorded over the multiple cores for each case was used. Cox proportional hazards regression was used to examine associations of overall survival with HGF, MET and pMET expression levels, adjusted for relevant clinical variables. Associations between expression levels and HGF SNP rs5745709 genotypes were examined using linear regression models. Results. HGF and MET expression were not associated with overall survival in our series of EOC cases (p=0.48 and 0.90, respectively). pMET expression was associated with survival, but in the opposite direction of that hypothesized (HR 0.77, 95% CI 0.39-1.52 for moderate expression; HR 0.55, 95% CI 0.27-1.10 for strong expression; each referent to negative/weak, p=0.01). Expression levels were not significantly associated with HGF rs5745709 genotypes (p=0.80 for HGF expression, p=0.89 for MET, p=0.41 for pMET). Conclusion. HGF expression levels were not associated with overall survival or with HGF SNP genotypes that correlated with survival in a previous study. Functional studies such as this one are crucial as a follow-up to discovery-based studies in order to assess biologic plausibility of observed results. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 893. doi:10.1158/1538-7445.AM2011-893
The effect of core suture flexor tendon repair techniques on gliding resistance during static cycle motion and load to failure: a human cadaver study
The purpose of this study was to describe a modification of the Massachusetts General Hospital (MMGH) tendon repair and to compare it with three other suture techniques. Twenty human flexor digitorum profundus (FDP) tendons were randomly assigned to the modified Pennington (MP) suture and the MMGH suture. These were compared to the modified Kessler (MK) and Massachusetts General Hospital (MGH) sutures, using data from a previous study. All tendons were repaired with a similar epitendinous stitch and core sutures of 4-0 FiberWire. There was no significant difference in the normalized gliding resistance within the two-strand or four-strand core repair groups. The MP suture had significantly higher 2 mm gap force and ultimate load to failure than the MK suture. The MMGH suture had significantly higher 2 mm gap force and maximum failure ultimate load than the MGH suture. All repairs failed by knot unravelling.
Assessment of Hepatocyte Growth Factor in Ovarian Cancer Mortality
Abstract Background: We previously identified a panel of genes associated with outcome of ovarian cancer. The purpose of the current study was to assess whether variants in these genes correlated with ovarian cancer risk. Methods and Findings: Women with and without invasive ovarian cancer (749 cases, 1,041 controls) were genotyped at 136 single nucleotide polymorphisms (SNPs) within 13 candidate genes. Risk was estimated for each SNP and for overall variation within each gene. At the gene-level, variation within MSL1 (male-specific lethal-1 homolog) was associated with risk of serous cancer (p=0.03); haplotypes within PRPF31 (PRP31 pre-mRNA processing factor 31 homolog) were associated with risk of invasive disease (p=0.03). MSL1 rs7211770 was associated with decreased risk of serous disease (OR 0.81, 95% CI 0.66-0.98; p=0.03). SNPs in MFSD7, BTN3A3, ZNF200, PTPRS, and CCND1A were inversely associated with risk (p<0.05), and there was increased risk at HEXIM1 rs1053578 (p=0.04, OR 1.40, 95% CI 1.02-1.91). Conclusions: Tumor studies can reveal novel genes worthy of follow-up for cancer susceptibility. Here, we found that inherited markers in the gene encoding MSL1, part of a complex that modifies the histone H4, may decrease risk of invasive serous ovarian cancer. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4718.