Glutathione S-transferase P1 polymorphisms are associated with time to tumor progression in small cell lung cancer patients.

PURPOSE: Many of commonly used chemotherapeutics in lung cancer treatment are metabolized by glutathione-S transferases (GSTs). The placental isoform of GST (GSTP1) is the most abundant isoform in the lung. Polymorphisms within the GSTP1 may result in alterations in enzyme activity and change sensitivity to platinum-based chemotherapy. We investigated whether the polymorphism within the exons 5 and 6 of GSTP1 gene may change response to therapy, time to tumor progression (TTP) and overall survival in small cell lung cancer (SCLC) patients. METHODS: Ninety-four histologically confirmed patients with SCLC were enrolled in this study during 1995-2006. GSTP1 Ile105Val polymorphism in exon 5 and GSTP1 Ala- 114Val polymorphism in exon 6 were determined by using PCR-RFLP techniques. Associations between the GSTP1 polymorphisms and treatment response were evaluated using the chi-square test. Associations between the GSTP1 polymorphisms and TTP and overall survival were compared using Kaplan-Meier survival curves. RESULTS: We found no significant associations between exon 5 and exon 6 GSTP1 gene polymorphisms and response to therapy or overall survival. Patients carrying both variant exon 5 (Ile/Val or Val/Val) and variant exon 6 (Ala/Val) genotypes had significantly shorter TTP (5 vs. 8 months, p = 0.04). Moreover, patients with heterozygote exon 6 variant had presented with extensive-stage disease. CONCLUSION: No individual effect of variant alleles was found in relation to chemotherapy response, median TTP and overall survival. The carriage of both types of variant alleles may predict worse outcome.

Seroreactivity against PTEN-induced putative kinase 1 (PINK1) in Turkish patients with Behçet's disease.

BACKGROUND: Behçet's disease (BD) is a multisystem inflammatory disorder characterized by recurrent oral ulcers, genital ulcers and ocular inflammation, as well as skin, joint, vascular, pulmonary, central nervous system (CNS) and gastrointestinal tract manifestations. The etiopathogenesis of BD has not yet been identified; but it has generally been accepted that several environmental factors may induce an inflammatory attack in genetically susceptible individuals. In this study, we aimed to identify antigens that could elicit high-titer IgG responses by the serological analysis of recombinant expression of cDNA libraries method (SEREX). METHODS: We screened a human testis cDNA library with pooled sera obtained from 4 BD patients by SEREX. Antigens that were identified with the initial analysis were selected for seroreactivity analysis of a larger group of BD patients (n=78) and controls (n=66) by serological immunoscreening. RESULTS: We observed seroreactivity against 6 antigens using the pooled sera. These included rabaptin 5 (RABPT5), PTEN-induced putative kinase 1 (PINK1), switch associated protein 70 (SWAP70), interferon-induced protein with tetratricopeptide repeats 2 (IFIT2), ankyrin repeat domain 20 family, member A1 (ANKRD20A1), and an unknown antigen. Eleven out of 82 (13.4%) BD patients were found to have antibodies elicited against PINK1 antigen, when none of the control sera showed reactivity (p=0.001). There was no significant difference in the frequency of other defined antigens between the patient and control groups. However, among BD clinical sub-groups, anti-SWAP70 antibodies were found to associate with vascular involvement. DISCUSSION: In this study, antibodies against PINK1 were found to specifically associate with BD while SWAP70 antibody was associated with clinical sub-groups of BD. Although variations in both genetic background and environmental factors may affect the outcome of serological responses, our results suggest that serological screening can be used to identify antigens that elicit antibody responses associated with BD.