An association between plasma levels of α2-macroglobulin and α1-antitrypsin in PiMM and PiZZ individuals differing in COPD presentation.

INTRODUCTION: Compared to normal PiMM, individuals with severe α1-antitrypsin (AAT) PiZZ (Glu342Lys) genotype deficiency are at higher risk of developing early-onset chronic obstructive pulmonary disease (COPD)/emphysema associated with Z-AAT polymers and neutrophilic inflammation. We aimed to investigate putative differences in plasma levels of acute phase proteins (APP) between PiMM and PiZZ subjects and to determine plasma Z-AAT polymer levels in PiZZ subjects. MATERIALS AND METHODS: Nephelometric analysis of seven plasma APPs was performed in 67 PiMM and 44 PiZZ subjects, of whom 43 and 42, respectively, had stable COPD. Of the PiZZ-COPD patients, 21 received and 23 did not receive intravenous therapy with human AAT preparations (IV-AAT). Plasma levels of Z-AAT polymers were determined by Western blotting using specific mouse monoclonal antibodies (2C1 and LG96). RESULTS: In addition to lower plasma AAT, PiZZ patients had higher α2-macroglobulin (A2MG) levels than PiMM patients. In contrast, PiZZ who received IV-AAT had higher AAT values but lower A2MG values than PiZZ without IV-AAT. Regardless of the AAT genotype, AAT levels were inversely correlated with A2MG, and the AAT/A2MG ratio was correlated with lung diffusion capacity (DCLO%). All PiZZ patients had circulating Z-AAT polymer levels that correlated directly with A2MG. In PiZZ without IV-AAT therapy polymer levels correlated inversely with the ratio of forced expiratory volume in 1 s to forced vital capacity (FEV1/FVC). CONCLUSION: Combined measurement of plasma AAT and A2MG levels may be of clinical value in assessing the progression of COPD and requires further attention.

The expression of circulating miR-504 in plasma is associated with EGFR mutation status in non-small-cell lung carcinoma patients.

MicroRNAs (miRNAs), key regulators of gene expression at the post-transcriptional level, are grossly misregulated in some human cancers, including non-small-cell lung carcinoma (NSCLC). The aberrant expression of specific miRNAs results in the abnormal regulation of key components of signalling pathways in tumour cells. MiRNA levels and the activity of the gene targets, including oncogenes and tumour suppressors, produce feedback that changes miRNA expression levels and indicates the cell's genetic activity. In this study, we measured the expression of five circulating miRNAs (miR-195, miR-504, miR-122, miR-10b and miR-21) and evaluated their association with EPIDERMAL GROWTH FACTOR RECEPTOR (EGFR) mutation status in 66 NSCLC patients. Moreover, we examined the discriminative power of circulating miRNAs for EGFR mutant-positive and -negative NSCLC patients using two different data normalisation approaches. We extracted total RNA from the plasma of 66 non-squamous NSCLC patients (31 of whom had tumours with EGFR mutations) and measured circulating miRNA levels using quantitative reverse transcription polymerase chain reaction (RT-qPCR). The miRNA expression levels were normalised using two endogenous controls: miR-191 and miR-16. We found significant associations between the expression of circulating miR-504 and EGFR-activating mutations in NSCLC patients regardless of the normalisation approach used (p = 0.0072 and 0.0236 for miR-16 and miR-191 normalisation, respectively). The greatest discriminative power of circulating miR-504 was observed in patients with EGFR exon 19 deletions versus wild-type EGFR normalised to miR-191 (area under the curve (AUC) = 0.81, p < 0.0001). Interestingly, circulating miR-504 levels were significantly reduced in the v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS)-mutated subgroup compared to EGFR-mutated patients (p < 0.0030) and those with EGFR/KRAS wild-type tumours (p < 0.0359). Our study demonstrated the feasibility and potential diagnostic value of plasma miR-504 expression analysis to distinguish between EGFR-mutated and wild-type NSCLC patients. However, quality control and normalisation strategies are very important and have a major impact on the outcomes of circulating miRNA analyses.

SERPINA1 Gene Variants in Granulomatosis with Polyangiitis.

Alpha-1 antitrypsin (A1AT) deficiency is one of the most common genetic disorders in Caucasian population. There is a link between granulomatosis with polyangiitis (GPA) and most frequent variants of SERPINA1 gene encoding severe alpha-1 antitripsin deficiency. However, the potential effect of Pi*Z, Pi*S as well as other SERPINA1 variants on clinical course of vasculitis are not well understood. The aim of the study was to analyze the potential effect of A1AT protein phenotype representing the SERPINA1 gene variants on the clinical course of GPA. The study group consisted of 64 subjects with GPA, stratified according to the disease severity: patients in active phase (group I, n = 12), patients during remission on treatment (group II, n = 40) or untreated (group III, n = 12). Normal Pi*MM SERPINA1 genotype was detected by means of real-time polymerase chain reaction (PCR) or direct sequencing in 59 patients, Pi*MZ genotype in 2, and Pi*IM, Pi*MS or Pi*SZ in 1 patient respectively. The patients with abnormal Pi*Z, Pi*S, or Pi*I allele constituted 17% in group I, 5% in group II, and 8% in group III. The serum content of A1AT and high sensitivity C-reactive protein (hsCRP) assessed by nephelometry did not differ between the groups. Interestingly, the mean serum antiPR3-antibodies level detected by Elisa method was significantly greater in the GPA patients with Pi*Z, Pi*S, or Pi*I SERPINA1 variants than in the Pi*MM homozygotes. In summary, heterozygous Pi*MZ, Pi*MS, and Pi*SZ genotype was detected in 7.8% of total group of GPA patients, and in 10.5% of those with lung lesions. The abnormal alleles of Pi*S and Pi*Z may affect the clinical course of the disease.