The level of evidence for many assays is limited, and only ERCC1 mRNA levels have been analyzed extensively. The impact of ERCC1 should be fully validated in prospective clinical trials.

No abstract

Several lines of evidence support a mitochondrial dysfunction in major psychiatric disorders. The objective of this study was to determine whether mitochondrial DNA (mtDNA) expression or content are implicated in the mitochondrial dysfunction observed in schizophrenia (SCH), bipolar disorder (BD), and major depressive disorder (MDD). MtDNA gene expression and mtDNA content (including the MT-ND4 deletion) were measured by RT-qPCR and qPCR, respectively. Post-mortem brain tissue from 60 subjects, divided evenly into four diagnostic groups (SCH, BD, MDD, and control (C)), was analyzed. MT-ND1 gene expression was significantly increased in the BD group compared with the C group. MDD and SCH patients showed a similar pattern of mtDNA expression, which was different from that in BD patients. Similarly, a larger number of MDD and SCH patients tended to have the MT-ND4 gene deleted compared with BD and C subjects. However, no other significant differences were observed in mtDNA gene expression and mtDNA content. Notably, high variability was observed in the mtDNA gene expression and content in each diagnostic group. Previous studies and the present work provide evidence for a role of mtDNA in SCH, BD and MDD. However, further studies with larger patient and control groups as well as by analyzing distinct brain regions are needed to elucidate the role of mtDNA in major psychiatric disorders.

Evidence suggests that myelin alterations could predispose to schizophrenia. Reduced expression of several myelin genes has been observed in schizophrenia patients. Recently, we identified the discoidin domain receptor 1 (DDR1; located at human chromosome 6p21.3) as a myelin gene in the mouse model and in a human oligodendroglial cell line. In the present study we screened for single nucleotide polymorphisms (SNPs) in the DNA from 100 schizophrenia patients. We identified a novel mutation within exon 10 that produces the amino-acid substitution N502S in the a-d isoforms, and M475V in the e isoform. However the frequency of the mutation (2%) was similar in schizophrenia patients and in control subjects. In a casecontrol assessment with 389 schizophrenic patients and 615 controls, we identified one SNP (SNP9, rs1049623) associated with schizophrenia (odds ratio = 1.44, 95% confidence interval: 1.15-1.79, adjusted P = 0.0016). This association was confirmed in haplotype analysis; the SNPs 9-10-11 (rs1049623, rs2267641 and rs2239518) haplotype remaining significant even after adjustment for multiple testing (adjusted P = 0.0136). Of note was a strong gender dependence in the association, that is, statistical significance restricted to men (adjusted P-value = 0.0002). Regression analysis of DDR1 mRNA expression in peripheral blood lymphocytes from schizophrenia patients showed that the presence of the G allele significantly decreased the relative number of mRNA copies in a dose-dependent manner (P = 0.003). These data suggest that the risk haplotype tags a cis-acting variant involved in the transcription regulation system of the gene. In conclusion, we propose the DDR1 as a new susceptibility gene for schizophrenia.

No abstract

Hereditary breast and ovarian cancer syndrome (HBOC) is partly due to the presence of mutations in the BRCA genes. Triple-negative (TN) breast cancer (BC) shares histological characteristics with germline BRCA1 mutation-associated tumours. We have investigated the metabolic profiles of human breast cancer (BC) cell lines carrying BRCA1 pathogenic mutations by non-targeted liquid chromatography coupled to mass spectrometry technology. Based on our in vitro results, we performed a targeted metabolomic analysis of plasma samples from TN HBOC patients taking into account their BRCA1 genotype. BRCA1 promoter hypermethylation and the BRCAness phenotype of BC cell lines were also studied. The purpose of this study was to determine the metabolic signature of HBOC syndrome and TNBC patients and to evaluate the potential contribution of the metabolites identified to the genetic diagnosis of breast cancer. The present results show the existence of a differential metabolic signature for BC cells based on the BRCA1 functionality. None of the studied BC cell lines presented hypermethylation of the BRCA1 promoter region. We provide evidence of the existence of free methylated nucleotides capable of distinguishing plasma samples from HBOC patients as BRCA1-mutated and BRCA1 non-mutated, suggesting that they might be considered as BRCA1-like biomarkers for TNBC and HBOC syndrome.

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In this review, we deal with six groups of cytotoxic drugs commonly used in the treatment of non-small cell lung cancer (NSCLC). Although there are many reviews of thymidylate synthase (TS) and antifolate inhibitors, in this article, we have tried to highlight aspects that are more important for medical oncologists to consider when treating NSCLC patients. There is compelling evidence that TS gene transcripts and TS polymorphisms could be used to decide which patients can best benefit from adjuvant chemotherapy approaches, especially in colorectal cancer, and not less importantly, to tailor chemotherapy in metastatic NSCLC when using drugs akin to fluorouracil, such as pemetrexed. Secondly, cisplatin is central to chemotherapy combinations and evidence indicates that DNA repair capacity influences response to cisplatin-based regimens. ERCC1 gene transcript stands out as a predictive marker of cisplatin sensitivity. Thirdly, preliminary studies indicate that upregulation of beta-tubulin III correlates with response to paclitaxel and vinorelbine. Fourthly, overexpression of ribonucleotide reductase can influence response to gemcitabine. Fifthly, we describe mechanisms of resistance to topoisomerase I inhibitors, although this subject has not yet been completely elucidated. Finally, to understand the mechanisms of resistance to EGF-R inhibitors, which have been shown to be useful in many different types of cancer, the Src-STAT signaling pathways are described here in detail. Hopefully, the assessment of Src and of STAT-3 can be implemented as predictive markers.