Randomized, controlled, blinded trial of Tisseel/Tissucol for mesh fixation in patients undergoing Lichtenstein technique for primary inguinal hernia repair: results of the TIMELI trial.

OBJECTIVE: Test the hypothesis that fibrin sealant mesh fixation can reduce the incidence of postoperative pain/numbness/groin discomfort by up to 50% compared with sutures for repair of inguinal hernias using the Lichtenstein technique. BACKGROUND: Inguinal hernia repair is the most common procedure in general surgery, thus improvements in surgical techniques, which reduce the burden of undesirable postoperative outcomes, are of clinical importance. METHODS: A randomized, controlled, patient- and evaluator-blinded study (Tissucol/Tisseel for MEsh fixation in LIchtenstein hernia repair [TIMELI]; trial NCT00306839) was conducted among patients eligible for Lichtenstein repair of uncomplicated unilateral primary inguinal small-medium sized hernia. Patients were subject to mesh fixation with either fibrin sealant or sutures. Main outcome measures were visual analogue scale (VAS) assessments for "pain," "numbness," and "groin discomfort" on a scale of 0 = best and 100 = worst outcome. The primary endpoint was a composite that evaluated the prevalence of chronic disabling complications (VAS score >30 for pain/numbness/groin discomfort) at 12 months after surgery. RESULTS: In total, 319 patients were randomized between January 2006 and April 2007 (159 fibrin sealant, 160 sutures). At 12 months, the prevalence of 1 or more disabling complication was significantly lower in the fibrin sealant group than in the sutures group (8.1% vs 14.8%; P = 0.0344). Less pain was reported in the fibrin sealant group than in the sutures group at 1 and 6 months (P = 0.0132; P = 0.0052), as reflected by a lower proportion of patients using analgesics in the fibrin group over the study duration (65.2% vs 79.7%; P = 0.0009). Only 3 of 316 patients (0.9%) experienced recurrence. The incidences of wound-healing complications and other adverse events were comparable between groups. CONCLUSIONS: Fibrin sealant for mesh fixation in Lichtenstein repair of small-medium sized inguinal hernias is well tolerated and reduces the rate of pain/numbness/groin discomfort by 45% relative to sutures without increasing hernia recurrence (NCT00306839).

Analysis of the ERalpha germline PvuII marker in breast cancer risk.

BACKGROUND: Prolonged exposure to estrogens was found to be a risk factor for breast cancer. The molecular mechanism has been suggested to be the binding of estrogen receptors in mammary tissue, which promotes the proliferation of breast tissue. Different biomarkers mapping estrogen receptor alpha (ESR1) have been associated with breast cancer risk, although the size of the effect is not consistent among different reports. Variation in the estrogen receptor gene PvuII has been associated with an increased risk of developing breast cancer. However, some studies suggest that its effect might be constrained to a definite subgroup of patients. MATERIAL/METHODS: In this study the involvement of PvuII in breast cancer was analyzed in an independent sample of 444 unrelated breast cancer cases and 704 controls of Spanish origin. A case-control comparison was performed and the genotype distributions examined according to different tumor and population parameters. RESULTS: A trend towards association was observed in adjusted case-control association analysis (p=0.07). PvuII was associated with the familial forms of breast cancer (OR=3.81, p=0.02). T allele frequency was higher among patients with highly differentiated tumors (p=0.02), positive for steroid receptors (p=0.06), and negative for p53 (p=0.02). However, the PvuII genetic background did not affect disease-free survival time (p=0.65). CONCLUSIONS: The PvuII T allele may be a germline risk factor for familial forms of breast cancer and is associated with a specific subset of immunohistochemical tumor phenotype.

Exploring allelic imbalance within paraffin-embedded tumor biopsies using pyrosequencing technology.

BACKGROUND: The comparison of molecular genetic changes in healthy and pathological tissues has historically led to the identification of oncogenes and tumor suppressor genes. It is very common that studies investigating loss of heterozygosity are carried out retrospectively on paraffin-embedded samples. METHODS: In this study, we evaluated the power of pyrosequencing for determining the loss of heterozygotic regions. The present method uses the fact that pyrosequencing is an accurate, sensitive and reproducible technique. The method is also simple to perform, with results available in 96-well format, making the assays amenable to automation. Thus, we analyzed nine single nucleotide polymorphisms along 1 Mb between the EMSY and PAK1 genes on 11q13, a region frequently rearranged in different tumors and cell lines. We assessed the study using samples from breast cancer and thyroid cancer biopsies. RESULTS AND CONCLUSIONS: We conclude that this technique is capable of detecting variations of >10% in allele loss. However, strong allele imbalances were detected, depending on the origin of the sample. Seven out of the nine markers used exhibited differential allele amplification, depending on the DNA quality (p<0.01).

Genetic analysis of caveolin-1 and eNOS genes in colorectal cancer.

Caveolae are involved in physical compartmentalization between different groups of signaling events. Its main component, CAV1, modulates different pathways in cellular physiology. The emerging evidence pointing to the role of CAV1 in cancer led us to study whether different alleles of this gene are associated with colorectal cancer (CRC). Since one of the most characterized enzymes regulated by CAV1 is eNOS, we decided to include both genes in this study. We analyzed five SNPs in 360 unrelated CRC patients and 550 controls from the general population. Two of these SNPs were located within eNOS and three within the CAV1 gene. Although haplotype distribution was not associated with CRC, haplotype TiA (CAV1) was associated with familiar forms of CRC (p<0.05). This was especially evident in CRC antecedents and nuclear forms of CRC. If both CG (eNOS) and TiA (CAV1) haplotypes were taken together, this association increased in significance. Thus, we propose that CAV1, either alone or together with eNOS alleles, might modify CRC heritability.

Pyrosequencing protocol requiring a unique biotinylated primer.

BACKGROUND: DNA sequencing has markedly changed the nature of biomedical research. Large-scale sequencing projects have generated several millions of potential polymorphisms widespread in the human genome requiring validation and incorporation into screening panels. As a consequence, high-throughput analysis of these variants in different populations of interest is now the cornerstone of structural genomics. Pyrosequencing is a versatile technique allowing an easy 96-well typing format. However, every polymorphism requires a specific labeled primer to generate a single-stranded DNA fragment containing the region of interest. METHODS: We describe how with an adjusted primer stoichiometry we can standardize the labeling of every amplicon with a single biotinylated universal primer (BM13S). RESULTS: We circumvent the need for specific biotinylated primers for each single-nucleotide polymorphism (SNP) under study. As an example, we assessed this novel protocol by genotyping three SNPs mapping calpain-10, caveolin-1 and CYP19A1. CONCLUSION: The present approach represents an alternative to standard pyrosequencing protocols, since it requires a single biotinylated primer that is suitable for each SNP under study.