Diagnostic Utility of Genetic and Immunohistochemical H3-3A Mutation Analysis in Giant Cell Tumour of Bone.

To validate the reliability and implementation of an objective diagnostic method for giant cell tumour of bone (GCTB). H3-3A gene mutation testing was performed using two different methods, Sanger sequencing and immunohistochemical (IHC) assays. A total of 214 patients, including 120 with GCTB and 94 with other giant cell-rich bone lesions, participated in the study. Sanger sequencing and IHC with anti-histone H3.3 G34W and G34V antibodies were performed on formalin-fixed, paraffin-embedded tissues, which were previously decalcified in EDTA if needed. The sensitivity and specificity of the molecular method was 100% (95% CI: 96.97-100%) and 100% (95% CI: 96.15-100%), respectively. The sensitivity and specificity of IHC was 94.32% (95% CI: 87.24-98.13%) and 100% (95% CI: 93.94-100.0%), respectively. P.G35 mutations were discovered in 2/9 (22.2%) secondary malignant GCTBs and 9/13 (69.2%) GCTB after denosumab treatment. We confirmed in a large series of patients that evaluation of H3-3A mutational status using direct sequencing is a reliable tool for diagnosing GCTB, and it should be incorporated into the diagnostic algorithm. Additionally, we discovered IHC can be used as a screening tool. Proper tissue processing and decalcification are necessary. The presence of the H3-3A mutation did not exclude malignant GCTB. Denosumab did not eradicate the neoplastic cell population of GCTB.

Pigmented/melanocytic malignant perivascular epithelioid cell tumor with TFE3-SFPQ(PSF) rearrangement - a challenging diagnosis of PEComa family of tumors.

We here report a case of a distinct subtype of pigmented/melanocytic malignant PEComa with TFE3-SFPQ(PSF) rearrangement. The tumor involved the iliac region and clinically mimicked metastatic melanoma. The immunohistochemical assessment was supplemented with molecular studies including fluorescence in situ hybridization (FISH) and next-generation sequencing sarcoma panel (NGS). We also discuss the differential diagnosis of intraabdominal PEComas and emphasise the recent molecular reports on the TFE3 rearranged tumors.

The retrospective molecular analysis of large or giant congenital melanocytic nevi in a group of Polish children.

BACKGROUND: Large and giant congenital melanocytic nevi (CMN), benign naevomelanocytic proliferations derived from neural crests, with a projected adult size (PAS) ≥ 20 cm, are connected to a high risk of melanoma and neurocutaneous melanosis. Among several factors, genetic alterations seem to be involved in tumorigenesis. The aim of the present study was to analyse the mutation status of NRAS and BRAF genes in resection specimens from large or giant CMN in a group of Polish patients. MATERIAL AND METHODS: The formalin-fixed, paraffin-embedded resection specimens from 18 patients, fixed in the years of 2006 to 2017, were included in the study. The regions containing the highest load of melanocytes were macrodissected prior to DNA isolation. The NRAS and BRAF mutation status was evaluated using qPCR. RESULTS: We detected activating mutations in NRAS gene (codons: 12 and 61) in 7 out of the 18 (38.9%) patients. No BRAF mutations were found. CONCLUSION: Our study, the first molecular analysis of large/giant CMN in Polish patients, supports the hypothesis that NRAS mutation in codon 61 are frequent, recurrent mutations in large/giant CMN. Moreover, we show, for the first time, that NRAS mutations in codon 12 (p.Gly12Asp) can be also detected in giant CMN. The exact role of these genetic alterations in CMN formation remains to be elucidated.

PPARG2 Pro12Ala and TNFα -308G>A Polymorphisms Are Not Associated with Heart Failure Development in Patients with Ischemic Heart Disease after Coronary Artery Bypass Grafting.

TNFα and PPARγ are important modulators of metabolism, inflammation, and atherosclerosis. Coronary artery disease is the leading cause of heart failure (HF). The aim of the study was to assess whether polymorphisms of the TNFα (-308G>A) and PPARG2 (Pro12Ala) genes are associated with the risk of developing HF by patients with ischemic heart disease. Methods. 122 patients without HF (aged 63 ± 8.8 years, 85% males) with confirmed coronary artery disease qualified for coronary bypass grafting were enrolled in the study. After the procedure, they were screened for cardiac parameters. Those with elevated NT-proBNP or diminished left ventricular ejection fraction during follow-up were assigned to the HF group (n=78), and the remaining ones to the non-HF group (n=44). The TNFα -308G>A and PPARG2 Pro12Ala polymorphisms were detected using the TaqMan method. Results. The distributions of TNFα -308G>A and PPARG2 Pro12Ala did not differ between the HF and non-HF groups (-308G>A: 16% vs. 11.4% of alleles; Pro12Ala: 23.9% vs. 20.5% of alleles, respectively). IL-6 concentration in the plasma of TNFα A-allele carriers at months 1 and 12 after CABG was higher in the HF group compared to the non-HF group (1 month after CABG: 5.3 ± 3.4 vs. 3.1 ± 2.9, p<0.05; 12 months after CABG: 4.2 ± 3,9 vs. 1.4 ± 1.2, p<0.01, respectively). Both polymorphisms were not related to changes in the plasma TNFα concentration or other parameters related to HF. Conclusions. Our study did not reveal any correlation between the PPARG2 Pro12Ala and TNFα -308G>A polymorphisms and development of HF in patients with ischemic heart disease after coronary bypass grafting.

Myocardial Expression of PPARγ and Exercise Capacity in Patients after Coronary Artery Bypass Surgery.

Activation of PPARs may be involved in the development of heart failure (HF). We evaluated the relationship between expression of PPARγ in the myocardium during coronary artery bypass grafting (CABG) and exercise tolerance initially and during follow-up. 6-minute walking test was performed before CABG, after 1, 12, 24 months. Patients were divided into two groups (HF and non-HF) based on left ventricular ejection fraction and plasma proBNP level. After CABG, 67% of patients developed HF. The mean distance 1 month after CABG in HF was 397 ± 85 m versus 420 ± 93 m in non-HF. PPARγ mRNA expression was similar in both HF and non-HF groups. 6MWT distance 1 month after CABG was inversely correlated with PPARγ level only in HF group. Higher PPARγ expression was related to smaller LVEF change between 1 month and 1 year (R = 0.18, p < 0.05), especially in patients with HF. Higher initial levels of IL-6 in HF patients were correlated with longer distance in 6MWT one month after surgery and lower PPARγ expression. PPARγ expression is not related to LVEF before CABG and higher PPARγ expression in the myocardium of patients who are developing HF following CABG may have some protecting effect.

PPAR Gamma Expression Levels during Development of Heart Failure in Patients with Coronary Artery Disease after Coronary Artery Bypass-Grafting.

Genetic research has elucidated molecular mechanisms of heart failure (HF). Peroxisome proliferator-activated receptors (PPARs) seem to be important in etiology of HF. The aim of study was to find the correlation between PPARγ expression during development of HF in patients and coronary artery disease (CAD) after coronary artery bypass-grafting (CABG). Methods and Results. We followed up 157 patients (mean age 63) with CAD without clinical, laboratory, or echo parameters of HF who underwent CABG. Clinical and laboratory status were assessed before CABG and at 1, 12, and 24 months. During CABG slices of aorta (Ao) and LV were collected for genetic research. HF was defined as LVEF <40% or NT-proBNP >400 pg/mL or 6MWT <400 m. Patients were divided into 2 groups: with and without HF. PPARγ expression in Ao and LV was not increased in both groups at 2-year follow-up. Sensitivity of PPARγ expression in Ao above 1.1075 in detection of HF was 20.5% (AUC 0.531, 95% CI 0.442-0.619). Positive predictive value (Ppv) was 85.7%. Sensitivity and specificity of PPARγ expression in the LV in detection of HF were 58% and 92.9%, respectively (AUC 0.540, 95% CI 0.452-0.626). Ppv was 73.2%. Conclusion. PPARγ expression in Ao and LV was comparable and should not be used as predictive factor for development of HF in patients with CAD after CABG.