Barbara Wysoczanska

Introduction Telomerase reverse transcriptase (TERT) is a catalytic subunit of telomerase that maintains genome stability by maintaining telomere length (TL). The massive proliferation of donor cells in the recipient’s body for engraftment results in accelerated telomere shortening. Genetic variability within the TERT gene affects telomerase activity, and was shown to influence of haematopoietic stem cell transplantation (HSCT) outcome. In the present study, we aimed to analyse the effect of recipient and donor TL and TERT single nucleotide polymorphism (SNP) on the occurrence of post-HSCT complications. Methods Our study included 120 recipient-donor pairs. TERT promoter (TERTp) SNP (rs2853669) SNP variant was detected with the use of the LightSNiP typing assay employing real-time polymerase chain reaction (PCR) amplifications. Telomere length measurements were performed using qPCR test kits (ScienCell’s Absolute Human Telomere Length Quantification qPCR Assay Kit [AHTLQ], Carlsbad, CA, USA). Results The presence of TERTp rs2853669 T allele in the recipient was associated with a higher risk for acute graft-versus-host-disease (aGvHD) manifestation (p = 0.046) and a significantly shorter aGvHD-free survival (p = 0.041). The latter association was further confirmed in a Cox proportional hazards model (p = 0.043). However, no statistically significant association between telomere length and post-transplant complications was observed. Furthermore, we found that shorter TL characterized donors of patients with late complete chimerism at 180 day after HSCT (p = 0.011). Conclusion Our results suggest that recipient allele TERTp rs2853669 T is a marker of unfavourable outcome in the context of aGvHD. Shorter TL in donors could be associated with later achievement of complete chimerism.

Background/Objectives: The balance between regulatory and Th17 cells plays an important role in maintaining the immune tolerance after kidney transplantation (KTx) which is essential for transplantation success, defined as a long graft survival and an absence of organ rejection. The present study aimed to assess whether the pretransplant characteristics of IL-17A and IL-17F, their receptors, as well as miR-146a-5p, an miRNA associated with IL-17A/F regulation, can predict KTx outcomes. Methods: A group of 108 pre-KTx dialysis patients and 125 healthy controls were investigated for single nucleotide substitutions within genes coding for IL-17A, IL-17F, their IL-17RA/RC receptors, and miR-146a-5p. Genotyping was performed using LightSNiP assays. In addition, IL17-A/F serum concentrations were determined using ELISA while miR-146a-5p expression was analyzed by RT-PCR. Results: The IL-17F (rs763780) G allele prevailed in KTx recipients as compared to healthy individuals (OR = 23.59, p < 0.0001) and was associated with a higher IL-17F serum level (p = 0.0381) prior to transplantation. Higher miR-146a-5p expression before KTx was more frequently detected in recipients with an increased IL-17A serum concentration (p = 0.0177). Moreover, IL-17A (rs2275913) GG homozygosity was found to be associated with an increased incidence of deaths before KTx (OR = 4.17, p = 0.0307). T-cell or acute rejection episodes were more frequently observed among patients with the C allele of miR-146a-5p (rs2910164) (OR = 5.38, p = 0.0531). IL17-RA/-RC genetic variants (p < 0.05) seem to be associated with eGFR values. Conclusions: These results imply that IL-17F (rs763780) polymorphism is associated with the serum level of this cytokine and may be related to the risk of renal disease and transplant rejection together with miR-146a-5p (rs2910164), while the IL-17A (rs2275913) genotype may affect patients’ survival before KTx.

The molecular mechanisms of telomerase reverse transcriptase (TERT) upregulation in breast cancer (BC) are complex. We compared genetic variability within TERT and telomere length with the clinical data of patients with BC. Additionally, we assessed the expression of the TERT, MYC, TP53 and SP1 genes in BC patients and in BC organoids (3D cell cultures obtained from breast cancer tissues). We observed the same correlation in the blood of BC patients and in BC organoids between the expression of TERT and TP53. Only in BC patients was a correlation found between the expression of the TERT and MYC genes and between TP53 and MYC. We found associations between TERT genotypes (rs2735940 and rs10069690) and TP53 expression and telomere length. BC patients with the TT genotype rs2735940 have a shorter telomere length, but patients with A allele rs10069690 have a longer telomere length. BC patients with a short allele VNTR-MNS16A showed higher expression of the SP1 and had a longer telomere. Our results bring new insight into the regulation of TERT, MYC, TP53 and SP1 gene expression related to TERT genetic variability and telomere length. Our study also showed for the first time a similar relationship in the expression of the above genes in BC patients and in BC organoids. These findings suggest that TERT genetic variability, expression and telomere length might be useful biomarkers for BC, but their prognostic value may vary depending on the clinical parameters of BC patients and tumor aggressiveness.