OP0105 miRNOME PROFILE IN PATIENTS WITH AXIAL SPONDYLOARTHRITIS

Background

microRNAs (miRNAs) are small non-coding RNAs regulating up to 60 % of human mRNAs, including genes related to axial spondyloarthritis (axSpA) (1).

Objectives

This study aims to profile miRNome and to identify candidate miRNAs determining disease severity in patietns with non-radiographic (nr) and radiographic (r) axSpA.

Methods

The miRNome profiling experiment included peripheral blood mononuclear cells (PBMCs) of 96 subjects (38 patients with nr-axSpA, 38 patients with r-axSpA and 20 healthy controls). Firstly, massive parallel sequencing on NextSeq 500 (MPS, Illumina) was performed for miRNA screening. Selected candidate miRNAs were further validated using the qRT-PCR system (SmartChip) on the validation cohort of 141 subjects (47 patients with nr-axSpA, 44 patients with r-axSpA and 50 healthy controls). We employed the DESeq2 algorithm and generalized linear modelling with a negative binomial assumption (GLM-NB) to evaluate the association of candidate miRNAs to axSpA subtype and clinical disease activity (ASDAS and CRP).

Results

MPS revealed 432 unique miRNAs in all samples. We identified 13 differently expressed miRNAs in axSpA patients compared to healthy controls, and 14 differently expressed miRNAs in axSpA patients with high to very high ASDAS compared to patients with inactive disease. Data from validation cohort revealed that the expression level of miR-4286 was higher in patients with very high disease activity compared to patients with inactive disease. Simultaneously, miR-4286 positively correlated with ASDAS. miR-4286 has been recently associated with osteogenesis and angiogenesis (2). None of the validated miRNAs was associated with the levels of CRP.

Conclusion

In this study, we identified that miR-4286 is related to disease activity and could play a role in the pathogenesis of axSpA.

References

[1]Prajzlerová K, Grobelná K, Hušáková M, et al. Association between circulating miRNAs and spinal involvement in patients with axial spondyloarthritis. PLoS One. 2017 Sep 22;12(9):e0185323.

[2]Yu H, Wang K, Liu P, et al. miR-4286 functions in osteogenesis and angiogenesis via targeting histone deacetylase 3 and alleviates alcohol-induced bone loss in mice. Cell Prolif. 2021 Jun;54(6):e13054.

Acknowledgements

Supported by MHCR No. 023728, BBMRI-CZ LM2018125 and SVV 260 523.

Disclosure of Interests

None declared

POS0444 PROFILING OF CIRCULATING miRNAs IN DIFFICULT-TO-TREAT RHEUMATOID ARTHRITIS

Background

Biologic (b-) and targeted synthetic (ts-) disease-modifying antirheumatic drugs (DMARDs) have brought significant progress in the treatment of rheumatoid arthritis (RA), but a significant proportion of RA patients still remain symptomatic despite treatment according to current recommendations. These patients have recently been defined as “difficult-to-treat (D2T)” RA (1). There is evidence that miRNA expression may play a role in the diagnosis and therapy of RA (2).

Objectives

In a retrospective study, we analyzed patients’ blood samples prior to b-/ts-DMARD treatment and profiled circulating miRNAs to predict the development of D2T-RA.

Methods

A total of 36 patients fulfilling the EULAR definition of D2T-RA (1) (mean age 59.1±10.7 yrs, 78% females), 36 patients with RA in sustained clinical remission on b-/ts-DMARDs at two consecutive examinations 12 wks apart (mean age 66.3±9.6 yrs, 78% females), and 36 healthy controls (mean age 61.1±7.7 yrs, 68% females) were included in the study. Blood samples were collected before initiation of b-/ts-DMARD. We profiled circulating miRNAs using the sequencing approach and differential expression analysis was performed using DESeq2 algorithm.

Results

The massive parallel sequencing of circulating miRNAs detected 814 quantifiable miRNAs and DESeq2 algorithm revealed 35 miRNAs with different concentrations in patients who developed D2T-RA compared to patients with RA who achieved sustained remission or healthy controls. Out of these miRNAs, miR-16-5p (1.5x) and miR-451a (2.1x) were downregulated and miR-126-3p (1.4x) was upregulated in D2T RA patients compared to controls. In addition, miR-101-3p (1.5x) was downregulated in D2T RA compared to RA patients. Except for miR-101-3p, these miRNAS have been previously associated with RA and might predict development of D2T disease prior to initiation of b-/ts-DMARD therapy.

Conclusion

We found four miRNAs as potential biomarkers differentiating patients who are at risk to develop difficult-to-treat disease compared to patients who have a chance of sustained remission even before initiation of biological or targeted synthetic DMARDs. Further studies with larger sample size are needed to validated these data.

References

[1]Nagy G, Roodenrijs NMT, Welsing PM, et al. EULAR definition of difficult-to-treat rheumatoid arthritis. Ann Rheum Dis. 2021 Jan;80(1):31-35.

[2]Filková M, Jüngel A, Gay RE, Gay S. MicroRNAs in rheumatoid arthritis: potential role in diagnosis and therapy. BioDrugs. 2012 Jun 1;26(3):131-41.

Acknowledgements

This work was supported by the project SVV 260 523, BBMRI-CZ LM2018125, and a project of the MHCR for conceptual research development No. 023728.

Disclosure of Interests

None declared.

Menopausal Transition: Prospective Study of Estrogen Status, Circulating MicroRNAs, and Biomarkers of Bone Metabolism

OBJECTIVE

Osteoporosis is associated with an impaired balance between bone resorption and formation, which in turn leads to bone loss and fractures. Many recent studies have underlined the regulatory role of microRNAs (miRNAs) in bone remodeling processes and their potential as biomarkers of osteoporosis. The purpose of this study was to prospectively examine the association of circulating miRNAs and bone biomarkers with estrogen status in women before and after oophorectomy, as well as in oophorectomized women on estrogen therapy.

METHODS

In this prospective study, we included 11 women before oophorectomy and hysterectomy and at 201 ± 24 days after the surgery. Another 11 women were evaluated 508 ± 127 days after oophorectomy and hysterectomy and after an additional 203 ± 71 days of estradiol treatment. Serum miRNAs were profiled by sequencing. Estrogen status and biomarkers of bone metabolism were quantified. Bone mineral density was assessed in the lumbar spine.

RESULTS

Our analysis revealed 17 miRNAs associated with estrogen levels. Of those miRNAs that were upregulated with estrogen deficiency and downregulated after estrogen therapy, miR-422a correlated with serum beta-carboxy-terminal type I collagen crosslinks (β-CTX) and procollagen 1 N-terminal propeptide (P1NP); and miR-1278 correlated with serum β-CTX, P1NP, osteocalcin, sclerostin, and Dickkopf-1(Dkk1). In contrast, we found an inverse association of miR-24-1-5p with estrogen status and a negative correlation with serum β-CTX, P1NP, osteoprotegerin, and sclerostin levels.

CONCLUSION

The reported miRNAs associated with estrogen status and bone metabolism could be potential biomarkers of bone pathophysiology and would facilitate studies on the prevention of postmenopausal osteoporosis. Our findings require validation in an extended cohort.

Functional analysis of germline ETV6 W380R mutation causing inherited thrombocytopenia and secondary acute lymphoblastic leukemia or essential thrombocythemia

Germline mutations in ETV6 gene cause inherited thrombocytopenia with leukemia predisposition. Here, we report on functional validation of ETV6 W380R mutation segregating with thrombocytopenia in a family where two family members also suffered from acute lymphoblastic leukemia (ALL) or essential thrombocythemia (ET). In-silico analysis predicted impaired DNA binding due to W380R mutation. Functional analysis showed that this mutation prevents the ETV6 protein from localizing into the cell nucleus and impairs the transcriptional repression activity of ETV6. Based on the germline ETV6 mutation, ET probably started with somatic JAK2 V617F mutation, whereas ALL could be caused by diverse mechanisms: high-hyperdiploidity; somatic deletion of exon 1 IKZF1 gene; or somatic mutations of other genes found by exome sequencing of the ALL sample taken at the diagnosis.

AB0038 CIRCULATING MICRORNAS IN HAND OSTEOARTHRITIS

Background:

microRNAs (miRNAs) are small non-coding RNAs that can ignite the degradation of mRNAs or inhibit the protein translation and are therefore essential for several physiological and pathological functions. miRNAs can regulate up to 60 % of human mRNA, including genes related to cartilage development, homeostasis, and OA pathology. For example, miR-9 inhibits matrix metalloproteinase 13 or miR-140 expression level correlates with the disease progression of knee OA (Zhang et al.; Chao et al.). Under certain circumstances, miRNAs can be released into the body fluids and easily be detected in the blood samples. Therefore, miRNAs are hot candidates as biomarkers for early diagnosis or structural progression of OA.

Objectives:

The aim of this study was to evaluate circulating miRNAs in patients with hand osteoarthritis (HOA) and healthy individuals. Simultaneously, we studied specific miRNAs in order to differentiate between erosive and non-erosive subsets of the disease.

Methods:

Eight patients with HOA (erosive: n=4, 3 females, mean age=63.7±7 yrs; non-erosive: n=4, 3 females, mean age= 62.4±6 yrs) and 4 healthy controls (3 females, mean age=63.5±7 yrs) were included in this study. Firstly, Advance TaqMan low-density assay (TLDA) was performed for the purpose of miRNA high-throughput screening. Differently expressed miRNAs were further verified by real-time qPCR on the validation cohort in 31 patients with hand OA (19 females, mean age=66.2±7 yrs, erosive: n=9, non-erosive: n=10, healthy controls: n=12).

Results:

TLDA profiling displayed 346 circulating miRNAs in plasma of patients with HOA and healthy controls. We demonstrated 40 differently expressed circulating miRNAs in patients with HOA compared with healthy controls. Using a real-time qPCR, we verified increased expression levels of 10 circulating miRNAs in patients with HOA compared with healthy controls, e.g. miR-191-5p (3.4 fold), miR-151a-3p (3.4 fold) or miR-222-3p (2.4 fold). We did not find any specific miRNA, which could distinct erosive from a non-erosive subset of the disease.

Conclusion:

Extensive profiling of circulating miRNAs revealed several miRNAs that can be associated with HOA and can help to better understand OA pathogenesis.

References:

[1]Chao, Yu, et al. “Expression of MiR-140 and MiR-199 in Synovia and Its Correlation with the Progression of Knee Osteoarthritis.” Medical Science Monitor, vol. 26, 2020, pp. 1–6, doi:10.12659/MSM.918174.

[2]Zhang, Hongxin, et al. “Downregulation of MicroRNA-9 Increases Matrix Metalloproteinase-13 Expression Levels and Facilitates Osteoarthritis Onset.” Molecular Medicine Reports, vol. 17, no. 3, 2018, pp. 3708–14, doi:10.3892/mmr.2017.8340.

Acknowledgements:

Supported by AZV NV18-01-00542, MHCR No. 023728

Disclosure of Interests:

None declared

AB0063 DIFFICULT-TO-TREAT RHEUMATOID ARTHRITIS: A BIOMARKER SCREENING PILOT STUDY

Background:

Despite modern therapeutic approaches, many patients with rheumatoid arthritis (RA) remain symptomatic after several cycles of treatment and may become so called Difficult-To-Treat (D2T)1. D2T RA is a multifactorial condition in which different factors may be major determinants of the persistence of signs and symptoms, which is seldom caused by drug resistance only2. Discovering new biomarkers is necessary to develop tailored therapies that will be effective in an individual patient at each stage of the disease.

Objectives:

The primary aim of this pilot study was to validate a target proteomic technique for the proteome profiling of the two cohorts of RA patients and controls. Moreover, we searched for potential plasma biomarker(s) predicting D2T RA.

Methods:

Seven RA patients with persistent remission on biological therapy in two consecutive examinations 12 wks apart (mean age 59.6±14 yrs), seven D2T RA patients fulfilling proposed EULAR definition of D2T RA1 (mean age 59.3±13 yrs), and six healthy controls (mean age 58.8±15 yrs) were included in this study. All subjects were females and their samples were collected before starting biological therapy. We employed Thermo Orbitrap Fusion paired with nano-flow UHPLC Dionex Ultimate 3000. Prior to quantification, 125 plasma proteins were modified by Peptiquant Plus Human kit to increase the sensitivity. Data were analysed by ANOVA and Tukey`s posthoc test with false-discovery-rate adjustment.

Results:

The target proteome profiling reliably quantified 92 from 125 labelled proteins. Our follow-up statistical analysis revealed ten plasma proteins, which significantly differed among groups. Notably, we found significantly different plasma levels of paraoxonase/arylesterase 1 (PON1), an esterase with an antioxidant characteristic preventing lipid peroxidation3, between RA patients and controls and between RA patients with persistent remission and D2T RA patients.

Conclusion:

Using target proteome profiling technique, we demonstrated PON1 as a potential biomarker of D2T RA. However, these results have to be validated on a larger cohort.

References:

[1]Nagy G, Roodenrijs NMT, Welsing PMJ, et al. EULAR definition of difficult-To-Treat rheumatoid arthritis. Annals of the Rheumatic Diseases 2021;80:31-5.

[2]de Hair MJH, Jacobs JWG, Schoneveld JLM, van Laar JM. Difficult-to-treat rheumatoid arthritis: an area of unmet clinical need. Rheumatology (Oxford, England) 2018 Jul 1;57(7):1135-1144.

[3]Isik A, Koca SS, Ustundag B, Celik H, Yildirim A. Paraoxonase and arylesterase levels in rheumatoid arthritis. Clinical Rheumatology 2007;26:342-8.

Acknowledgements:

This research was supported by MHCR No. 023728 and authors thank Proteomics Service Laboratory, Faculty of Science, Charles University for performing the LC–MS/MS analysis.

Disclosure of Interests:

None declared

Dynamic miRNA changes during the process of epileptogenesis in an infantile and adult-onset model

Temporal lobe epilepsy (TLE) is the most common epilepsy type. TLE onset in infancy aggravates features like severity, drug responsiveness, or development of comorbidities. These aggravations may arise from altered micro RNA (miRNA) expression specific to the early onset of the disease. Although the miRNA involvement in TLE is widely studied, the relationship between the onset-age and miRNA expression has not been addressed. Here, we investigated the miRNA profile of infantile and adult-onset TLE in rats combining sequencing and PCR. Since miRNA expression changes with the disease progression, we scrutinized miRNA dynamics across three stages: acute, latent, and chronic. We report that infantile-onset TLE leads to changes in the expression of fewer miRNAs across these stages. Interestingly, the miRNA profile in the acute stage of infantile-onset TLE overlaps in dysregulation of miR-132-5p, -205, and -211-3p with the chronic stage of the disease starting in adulthood. The analysis of putative targets linked the majority of dysregulated miRNAs with pathways involved in epilepsy. Our profiling uncovered miRNA expression characteristic for infantile and adulthood-onset epileptogenesis, suggesting the distinct biology underlying TLE in the onset age-dependent matter. Our results indicate the necessity of addressing the onset age as an important parameter in future epilepsy research.

Epilepsy miRNA Profile Depends on the Age of Onset in Humans and Rats

Temporal lobe epilepsy (TLE) is a severe neurological disorder accompanied by recurrent spontaneous seizures. Although the knowledge of TLE onset is still incomplete, TLE pathogenesis most likely involves the aberrant expression of microRNAs (miRNAs). miRNAs play an essential role in organism homeostasis and are widely studied in TLE as potential therapeutics and biomarkers. However, many discrepancies in discovered miRNAs occur among TLE studies due to model-specific miRNA expression, different onset ages of epilepsy among patients, or technology-related bias. We employed a massive parallel sequencing approach to analyze brain tissues from 16 adult mesial TLE (mTLE)/hippocampal sclerosis (HS) patients, 8 controls and 20 rats with TLE-like syndrome, and 20 controls using the same workflow and categorized these subjects based on the age of epilepsy onset. All categories were compared to discover overlapping miRNAs with an aberrant expression, which could be involved in TLE. Our cross-comparative analyses showed distinct miRNA profiles across the age of epilepsy onset and found that the miRNA profile in rats with adult-onset TLE shows the closest resemblance to the profile in mTLE/HS patients. Additionally, this analysis revealed overlapping miRNAs between patients and the rat model, which should participate in epileptogenesis and ictogenesis. Among the overlapping miRNAs stand out miR-142-5p and miR-142-3p, which regulate immunomodulatory agents with pro-convulsive effects and suppress neuronal growth. Our cross-comparison study enhanced the insight into the effect of the age of epilepsy onset on miRNA expression and deepened the knowledge of epileptogenesis. We employed the same methodological workflow in both patients and the rat model, thus improving the reliability and accuracy of our results.

SAT0477 A TWO-YEAR LONGITUDINAL STUDY COMPLETION, LONGITUNEAL STUDY, THE DIFFERENCE IN BONE LOSS IN PATIENTS WITH EROSIVE AND NON-EROSIVE HAND OSTEOARTHRITIS

Background:

Hand osteoarthritis (OA) and its more severe subset erosive hand OA are common causes of pain and morbidity. Some metabolic factors were suggested to be implicated in erosive disease. Few studies investigated differences in systemic bone loss between erosive and non-erosive hand OA.

Objectives:

To compare the change of bone mineral density (BMD) between patients with erosive and non-erosive hand OA in a two-year longitudinal study.

Methods:

Consecutive patients with symptomatic HOA fulfilling the American College of Rheumatology (ACR) criteria were included in this study. Erosive hand OA was defined by at least one erosive interphalangeal joint. All patients underwent clinical assessments of joint swelling and radiographs of both hands. DEXA examination of lumbar spine, total femur and femur neck was performed at the baseline and after two years.

Results:

Altogether, 141patients (15 male) with symptomatic nodal HOA were included in this study and followed between April 2012 and January 2019. Out of these patients, 80 had erosive disease after two years. The disease duration (p<0.01) was significantly higher in patients with erosive compared with non-erosive disease at baseline.

Osteoporosis (T-score <-2.5 SD) was diagnosed in 12.5% (9/72) of patients with erosive hand OA and in 8.06% (5/57) of patients with non-erosive hand OA at baseline. BMD was significantly lowered in patients with erosive compared with non-erosive disease at baseline (lumbar spine: 1.05g/cm2 vs. 1.13 g/cm2, p<0.05, total femur: 0.90 g/cm2 vs. 0.97 g/cm2, p<0.01 and femur neck: 0.86 g/cm2 vs. 0.91, p<0.05). T-scores of lumbar spine (-0.96 vs. -0.41 SD, p<0.05), total femur (-0.69 vs. -0.33 SD, p<0.05) and femur neck (-1.14 vs. -0.88 SD, p<0.05) were also significantly lowered in patients with erosive compared with non-erosive disease.

Two years, the BMD remained also significantly lowered in patients with erosive compared with non-erosive disease (lumbar spine: 1.05g/cm2 vs. 1.14 g/cm2, p<0.05, total femur: 0.92 g/cm2 vs. 0.97 g/cm2, p<0.05 and femur neck: 0.86 g/cm2 vs. 0.91, p<0.05), which was in agreement with the finding for T-scores of lumbar spine (-1.05 vs. -0.39 SD, p<0.05), total femur (-0.74 vs. -0.34 SD, p<0.01) and femur neck (-1.07 vs. -0.72 SD, p<0.01).

Conclusion:

These results suggest that patients with erosive hand OA are at higher risk for the development of general bone loss. Over two years patients with erosive disease had significant lower bone mineral density at all measured sites.

References:

[1]This work was supported by the project AZV no. 18-00542 and MHCR No. 023728.

Acknowledgments:

Project AZV no. 18-00542 and MHCR No. 023728

Disclosure of Interests:

Karel Pavelka Consultant of: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Speakers bureau: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Ladislav Šenolt: None declared, Olga Sleglova: None declared, Jiří Baloun: None declared, Olga Růžičková: None declared

FRI0002 S100A11 (CALGIZZARIN) IS RELEASED DURING NEUTROPHIL EXTRACELLULAR TRAPS FORMATION AND STIMULATES RELEASE OF IL-6 AND TNF IN RHEUMATOID ARTHRITIS

Background:

S100A11 protein, a member of S100 family, has been associated with several autoimmune inflammatory conditions such as rheumatoid arthritis (RA). Although the pathogenesis of autoimmune diseases is not fully understood, the formation of neutrophil extracellular traps (NETs) seems to play a certain role. Recent data indicate that S100A8/A9 is released via NETosis and can further augment inflammatory responses.

Objectives:

The aim of our study was to examine the association of S100A11 with NETs in RA.

Methods:

To assess the expression of S100A11 by neutrophils of RA synovial tissue (n=8), immunofluorescence staining of S100A11 and myeloperoxidase (MPO) was performed. The levels of S100A11 and MPO in RA synovial fluid (n=23) were measured by ELISAs (RayBiotech and Abcam), and the activity of peptidyl arginine deiminases (PADs) was measured by an in-house immunoassay. NETosis was induced by adding phorbol 12-myristate 13-acetate (PMA) to neutrophils from RA patients (n=7). Release of NETs was visualised by immunocytochemistry (n=7) and the presence of S100A11 in supernatants was analysed by ELISA (RayBiotech). Neutrophils purified from healthy donors (n=5) were stimulated by S100A11 and the release of cytokines TNF and IL-6 was measured by ELISA (RayBiotech).

Results:

S100A11 was expressed by synovial tissue neutrophils of the RA patients (n=8). The levels of S100A11 in the synovial fluid of RA patients (n=23) correlated with the levels of a NETosis marker MPO (r=0.562, p=0.005) and with PADs activity (r=0.690, p<0.001), which affects NETs immunogenicity. Neutrophils treated with LPS (n=7) did not up-regulate the secretion of S100A11 compared to unstimulated controls (0.23±0.05 vs. 0.29±0.07 ng/ml; p=ns). However, the release of S100A11 was markedly up-regulated in PMA-stimulated neutrophils undergoing NETosis compared to untreated controls (1.16±0.17 vs. 0.29±0.07 ng/ml; p<0.001). Moreover, diphenyleneiodoinum treatment abolished PMA-induced S100A11 secretion. By immunofluorescence staining (n=8) we demonstrated that neutrophils activated by PMA release NETs containing S100A11 protein. In addition, extracellular S100A11 augmented the inflammatory response of neutrophils from healthy donors (n=5) via IL-6 and TNF in comparison with unstimulated cells (0.39±0.11 vs. 0.05±0.01 pg/ml; p<0.05 and 0.31±0.06 vs. 0.09±0.03 pg/ml; p<0.05).

Conclusion:

Here we show for the first time that release of S100A11 by neutrophils is dependent on NETosis. Moreover, extracellular S100A11 augments the inflammatory response by inducing TNF and IL-6 secretion in neutrophils.

Acknowledgments:

Supported by MHCR 023728

Disclosure of Interests:

Adela Navratilova: None declared, Viktor Becvar: None declared, Jiří Baloun: None declared, Dres Damgaard: None declared, Claus Henrik Nielsen: None declared, Karel Pavelka Consultant of: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Speakers bureau: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Jiří Vencovský: None declared, Ladislav Šenolt: None declared, Lucie Andres Cerezo: None declared, David Veigl: None declared

AB0001 PLASMA miRNA PROFILE IN PATIENTS WITH HAND OSTEOARTHRITIS

Background:

MicroRNAs (miRNA) are short non-coding RNAs that can be involved in diverse physiological processes1. Aberrant miRNA profiles have been shown in various diseases including osteoarthritis (OA)2; for instance, miR-21-5p or miR-140 are known for their altered expression in osteoarthritic cartilage3,4. However, no screening of circulating miRNAs has been done in patients with hand OA (HOA) so far.

Objectives:

Our aim was to profile circulating miRNAs in plasma of patients with HOA in screening and validation cohort.

Methods:

We screened the expression of miRNA profiles in 4 patients with erosive (3 females, mean age=63.7±7 yrs) and 4 patients with non-erosive (3 females, mean age=62.4±6 yrs) HOA, and 4 control subjects (3 females, mean age=63.5±7 yrs). The validation cohort included 10 patients with erosive (7 females, mean age=67.5±7 yrs) and 10 patients with non-erosive (6 females, mean age=67.6±8 yrs) HOA, and 10 control subjects (8 females, mean age=64.3±8 yrs). Circulating miRNA screening were performed using TLDA and selected miRNAs were validated by qRT-PCR.

Results:

Profiling circulating plasma discovered 42 miRNAs from 754 analysed miRNAs with different concentration among subjects, including miR−23a−3p (1.7 fold), −222−3p (2.0 fold), and −30e−3p (13.0 fold) to be elevated in patients with HOA compared to control subjects. In addition, six miRNAs were distinctive between erosive and non-erosive HOA, e.g. hsa-miR-24-3p was 2.3 times lower and hsa-miR-576-5p was 3.4 times higher in erosive compared to non-erosive disease.

Out of these selected miRNAs, qRT-PCR validated 42 miRNAs and confirmed 11 miRNAs (e.g., miR−23a−3p or –222-3p) with different concentration between patients and controls. However, no miRNAs distinguished between erosive and non-erosive HOA, although miR-101-3p (4.5 fold) and -320b (13.7 fold) almost reached statistical significance.

Conclusion:

Based on our study, we identified 11 miRNAs that may have a potential as biomarkers of HOA. However, further studies on larger cohorts are needed.

References:

[1]Krol, J., Loedige, I. & Filipowicz, W. The widespread regulation of microRNA biogenesis, function and decay.Nat. Rev. Genet.11, 597–610 (2010).

[2]Coutinho De Almeida, R.et al.RNA sequencing data integration reveals an miRNA interactome of osteoarthritis cartilage.Ann. Rheum. Dis.78, 270–277 (2019).

[3]Wang, X.et al.MicroRNA-21-5p as a novel therapeutic target for osteoarthritis.Rheumatology (Oxford).58, 1485–1497 (2019).

[4]Swingler, T. E.et al.The function of microRNAs in cartilage and osteoarthritis.Clin. Exp. Rheumatol.37, 40–47 (2019).

Acknowledgments:

This work was supported by the project AZV no. NV18-01-00542 and MHCR No. 023728.

Disclosure of Interests:

Jiří Baloun: None declared, Aneta Pekacova: None declared, Tereza Kropackova: None declared, Veronika Horvathova: None declared, Klára Prajzlerová: None declared, Mária Filková: None declared, Karel Pavelka Consultant of: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Speakers bureau: Abbvie, MSD, BMS, Egis, Roche, UCB, Medac, Pfizer, Biogen, Jiří Vencovský: None declared, Ladislav Šenolt: None declared

Activation-induced deaminase and its splice variants associate with trisomy 12 in chronic lymphocytic leukemia

Activation-induced cytidine deaminase (AID) is a mutator enzyme essential for somatic hypermutation (SHM) and class switch recombination (CSR) during effective adaptive immune responses. Its aberrant expression and activity have been detected in lymphomas, leukemias, and solid tumors. In chronic lymphocytic leukemia (CLL) increased expression of alternatively spliced AID variants has been documented. We used real-time RT-PCR to quantify the expression of AID and its alternatively spliced transcripts (AIDΔE4a, AIDΔE4, AIDivs3, and AIDΔE3E4) in 149 CLL patients and correlated this expression to prognostic markers including recurrent chromosomal aberrations, the presence of complex karyotype, mutation status of the immunoglobulin heavy chain variable gene, and recurrent mutations. We report a previously unappreciated association between higher AID transcript levels and trisomy of chromosome 12. Functional analysis of AID splice variants revealed loss of their activity with respect to SHM, CSR, and induction of double-strand DNA breaks. In silico modeling provided insight into the molecular interactions and structural dynamics of wild-type AID and a shortened AID variant closely resembling AIDΔE4, confirming its loss-of-function phenotype.

MicroRNA and mesial temporal lobe epilepsy with hippocampal sclerosis: Whole miRNome profiling of human hippocampus

OBJECTIVE

Mesial temporal lobe epilepsy (mTLE) is a severe neurological disorder characterized by recurrent seizures. mTLE is frequently accompanied by neurodegeneration in the hippocampus resulting in hippocampal sclerosis (HS), the most common morphological correlate of drug resistance in mTLE patients. Incomplete knowledge of pathological changes in mTLE+HS complicates its therapy. The pathological mechanism underlying mTLE+HS may involve abnormal gene expression regulation, including posttranscriptional networks involving microRNAs (miRNAs). miRNA expression deregulation has been reported in various disorders, including epilepsy. However, the miRNA profile of mTLE+HS is not completely known and needs to be addressed.

METHODS

Here, we have focused on hippocampal miRNA profiling in 33 mTLE+HS patients and nine postmortem controls to reveal abnormally expressed miRNAs. In this study, we significantly reduced technology-related bias (the most common source of false positivity in miRNA profiling data) by combining two different miRNA profiling methods, namely next generation sequencing and miRNA-specific quantitative real-time polymerase chain reaction.

RESULTS

These methods combined have identified and validated 20 miRNAs with altered expression in the human epileptic hippocampus; 19 miRNAs were up-regulated and one down-regulated in mTLE+HS patients. Nine of these miRNAs have not been previously associated with epilepsy, and 19 aberrantly expressed miRNAs potentially regulate the targets and pathways linked with epilepsy (such as potassium channels, γ-aminobutyric acid, neurotrophin signaling, and axon guidance).

SIGNIFICANCE

This study extends current knowledge of miRNA-mediated gene expression regulation in mTLE+HS by identifying miRNAs with altered expression in mTLE+HS, including nine novel abnormally expressed miRNAs and their putative targets. These observations further encourage the potential of microRNA-based biomarkers or therapies.

[Use of Porous Hydrogel as a 3D Scaffold for the Growth of Leukemic B Lymphocytes]

BACKGROUND

Primary human B cells chronic lymphocytic leukemia undergoes apoptosis, from which they can be rescued by contact with stromal cells or by the addition of specific soluble factor, when cultured in vitro. For research purposes of the behavior of CLL cells we created 3D in vitro model in which we simulated appropriate microenvironment for CLL cells to allow study the mechanism of survival of these cells in long-term cultivation.

MATERIAL AND METHODS

Our aim was the scaffold structure to be geometrically similar to the 3D morphology of supporting bone marrow tissue in a trabecular bone; the 3D scaffold was also designed to conform to biocompatibility, sufficiently large surface area for cell attachment, high porosity for cell migration, proliferation and transport of nutrients. Another requirement was a partial transparency for inspection of cell model with optical techniques. We prepared 3D scaffolds from porous hydrogel poly (2-hydroxyethyl methacrylate) (pHEMA), poly (2-hydroxyethyl methacrylate-co-2-aminoethyl methacrylate) p (HEMA-co-AEMA) and p (HEMA-co-AEMA) modified with frequently used cell adhesion peptide Arg-Gly-Asp (RGD). All hydrogel scaffolds were manufactured in four pore diameters (125, 200, 300 and 350-450 μm). Scaffolds were tested with human bone marrow stromal cell line HS-5 and human embryonic kidney cell line HEK293.

RESULTS

Hydrogel scaffold p (HEMA-co-AEMA) modified with adhesion peptide Arg-Gly-Asp (RGD) with pore diameter of 350-450 μm demonstrated that it is a convenient system for 3D cell cultivation, since it promotes interaction between the cells and also between the cells and the material. This scaffold was used for seeding of co-cultivation system of HS-5 cells with CLL-cells, which were stimulated through the CD40L signaling pathway as well as via the IL-4 pathway. Viability of B-CLL cells was higher in the presence of both stimulators than with each alone.

CONCLUSIONS

We have shown that 3D scaffold technology is very useful for modeling of microsystems where the cancer cells behave like in their natural microenvironment.Key words: hematooncology - leukemia - hydrogel - stromal cells This work was supported by grant COST CZ LD15144 "Cellular and acellular grounds for regeneration of bones and teeth" awarded by the Ministry of Education, Youth and Sport of the Czech Republic. The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 6. 3. 2017Accepted: 26. 3. 2017.

Expression response of duplicated metallothionein 3 gene to copper stress in Silene vulgaris ecotypes

Metallothioneins (MTs) were identified as important players in metal metabolism. MT3 gene presents a key metallothionein controlling copper homeostasis in plants. We have selected one cupricolous and one non-cupricolous ecotype to isolate and analyse the MT3 gene in Silene vulgaris. For expression data comparison, we have also included other metal-tolerant ecotypes. Based on a S. vulgaris BAC library screening, we have identified and sequenced a genomic clone containing MT3 gene (SvMT3). We found that SvMT3 gene has been locally duplicated in a tandem arrangement. Expression analysis and complementation studies using yeast mutants showed that both copies of the SvMT3 gene were functional. Moreover, we examined the expression of MT3 gene(s) in selected ecotypes under different copper treatments to show the tissue-specific expression response to copper stress. We demonstrated that higher copper concentrations specifically affected MT3 expression among ecotypes. Our analysis shows that MT3a has similar expression pattern in cupricolous ecotypes while MT3b has common expression features shared by all metallophyte S. vulgaris ecotypes. Our data indicate that down-regulation of MT3b root expression in higher copper concentrations is associated with copper stress. We propose that there might be a specific regulation of SvMT3s transcription depending on the type of heavy metal tolerance.

Characterization of the HMA7 gene and transcriptomic analysis of candidate genes for copper tolerance in two Silene vulgaris ecotypes

Silene vulgaris possesses ecotype-specific tolerance to high levels of copper in the soil. Although this was reported a few decades ago, little is known about this trait on a molecular level. The aim of this study was to analyze the transcription response to elevated copper concentrations in two S. vulgaris ecotypes originating from copper-contrasting soil types - copper-tolerant Lubietova and copper-sensitive Stranska skala. To reveal if plants are transcriptionally affected, we first analyzed the HMA7 gene, a known key player in copper metabolism. Based on BAC library screening, we identified a BAC clone containing a SvHMA7 sequence with all the structural properties specific for plant copper-transporting ATPases. The functionality of the gene was tested using heterologous complementation in yeast mutants. Analyses of SvHMA7 transcription patterns showed that both ecotypes studied up-regulated SvHMA7 transcription after the copper treatment. Our data are supported by analysis of appropriate reference genes based on RNA-Seq databases. To identify genes specifically involved in copper response in the studied ecotypes, we analyzed transcription profiles of genes coding Cu-transporting proteins and genes involved in the prevention of copper-induced oxidative stress in both ecotypes. Our data show that three genes (APx, POD and COPT5) differ in their transcription pattern between the ecotypes with constitutively increased transcription in Lubietova. Taken together, we have identified transcription differences between metallifferous and non-metalliferous ecotypes of S. vulgaris, and we have suggested candidate genes participating in metal tolerance in this species.

Complexes of glutathione with heavy metal ions as a new biochemical marker of aquatic environment pollution

Reduced glutathione (GSH) plays a number of key roles in many biochemical pathways. This peptide is highly reactive and forms conjugates with other molecules via its sulfhydryl moiety. The interactions of the common heavy metal pollutant Cd(II) with GSH were determined by using the Brdicka reaction to evaluate whether this technique would be suitable as a biomarker. After GSH interaction with Cd(II) ions, two characteristic changes in the measured voltammogram were observed: Cat2 signal height decreased, and a new signal called P1 was found. The observed signal probably relates to the formation of a GSH-heavy metal ion complex adsorbed on the surface of the working electrode. When the interaction of GSH with cisplatin was studied, the same characteristic changes in the voltammogram were observed, which confirmed our hypothesis. Moreover, changes in the height of P1 and Cat2 signals with increasing time of GSH interaction with Cd(II) ions and/or cisplatin were also investigated. Cat2 peak height decreased proportionally with increasing time of interaction. This decrease can be explained by shielding of free sulfhydryl moiety by heavy metal ions, so it cannot catalyze the evolution of hydrogen from the supporting electrolyte. In addition, we found that, with increasing time of the interaction, the P1 signal was enhanced and shifted to more positive potentials for both Cd(II) ions and cisplatin.

Study of Interactions between Metallothionein and Cisplatin by using Differential Pulse Voltammetry Brdickás reaction and Quartz Crystal Microbalance

Treatment strategies for tumour diseases are progressively focusing on personalization of medicine. However, this focus requires methods revealing the early general biological mechanisms, including the formation anti-cancer drugs’ resistance. The low molecular mass protein metallothionein is thought to be the crucial for the formation of resistance in tumour treatment based on the platinum-cytostatics. The interactions between metallothionein (MT) and cisplatin were determined by the adsorptive transfer stripping technique coupled with the differential pulse votlammetry Brdickás reaction. The signals related to the MT-cisplatin complex appeared at −0.9 V. The formation of this complex depended on the time of interaction between cisplatin and MT. The complex formation was consequently confirmed by quartz crystal microbalance analyses. The formation of this complex was detectable even after a 20 s long interaction. Moreover, we detected presence of MT-cisplatin complex in the blood of male rats treated with this drug.

Electrochemical Determination of Low Molecular Mass Thiols Content in Potatoes (Solanum tuberosum) Cultivated in the Presence of Various Sulphur Forms and Infected by Late Blight (Phytophora infestans)

In the present paper potato plants were cultivated in the presence of ammonium sulphate or elemental sulphur supplementation into the soil to reveal the effects of different sulphur forms on content of nitrogen, phosphorus, potassium, calcium, magnesium and sulphur, and yield of tubers. During the investigation of the influence of different sulphur forms on yield of potato tubers we did not observe significant changes. Average weight of tubers of control plants per one experimental pot was 355 g. Application of sulphur in both forms resulted in moderate potato tubers weight reduction per one experimental pot compared to control group; average value ranged from 320 to 350 g per one experimental pot. Further we treated the plants with two different supplementation of sulphur with cadmium(II) ions (4 mg of cadmium(II) acetate per kilogram of the soil). The significantly lowest cadmium content (p < 0.05) was determined in tissues of plants treated with the highest dosage of elemental sulphur (0.64 mg Cd/kg) compared to control plants (0.82 mg Cd/kg). We also aimed our attention on the cadmium content in proteins, lipids or soluble carbohydrates and ash. Application of sulphate as well as elemental sulphur resulted in significant cadmium content reduction in lipid fraction compared to control plants. In addition to this we quantified content of low molecular mass thiols in potatoes tissues. To determine the thiols content we employed differential pulse voltammetry Brdicka reaction. After twelve days of the treatment enhancing of thiols level was observed in all experimental groups regardless to applied sulphur form and its concentration. Finally we evaluated the effect of sulphur supplementation on Phytophora infestans infection of potato plants.

An Electrochemical Detection of Metallothioneins at the Zeptomole Level in Nanolitre Volumes

An Electrochemical Detection of Metallothioneins at the Zeptomole Level in Nanolitre VolumesWe report on improvement of the adsorptive transfer stripping technique (AdTS) coupled with the differential pulse voltammetry Brdicka reaction to determine a thiol-protein. The current technique has been unable to generate reproducible results when analyzing very low sample volumes (nanolitres). This obstacle can be overcome technically by modifying the current transfer technique including cooling step of the adsorbed analyte. We tested the technique on determination of a promising tumour disease marker protein called metallothionein (MT). The detection limit (3 S/N) of MT was evaluated as 500 zeptomoles per 500 nL (1 pM) and the quantification limit (10 S/N) as 1,500 zeptomoles per 500 nL (3 pM). Further, the improved AdTS technique was utilized to analyze blood serum samples from patients with breast cancer. Based on the results obtained it can be concluded that the improved technique can be used to detect a thiolprotein in very low sample volumes and can also prevent interferences during the washing and transferring step.

Electrochemical determination of Ag-ions in environment waters and their action on plant embryos

We utilized liquid chromatography coupled with electrochemical detector (HPLC-ED) for analyzing of silver ions. The optimization of basic chromatographic parameters has been done. The detection limit (3 S/N) obtained were 20 nmol/dm(3). Influence of different interferences (anions and cations) on current response of silver ions has been described. Moreover, we used HPLC-ED to analyze waters of different purity including photographic emulsion, which naturally contained silver ions. We found out that content of silver ions in the emulsion was 1.57 x 0.03 mmol/dm(3). Moreover, we investigated influence of silver ions on early somatic embryos of Blue Spruce. We were interested in the issue how much silver ions can embryos uptake during four days long treatment. For this purpose, we used optimized HPLC-ED technique. The content increased with increasing treatment time and applied concentration. We also studied how silver ions can influence thiols content in the treated embryos. For these purposes we used adsorptive transfer stripping voltammetry in connection with differential pulse voltammetry--Brdicka reaction. It clearly follows from the obtained results that content of thiols increased with increasing treatment time and applied concentration.