Alexander Tivtikyan

Dr. Alexander Tivtikyan

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Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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MZMaria Zvereva
Maria Zvereva
EPEduard Pisarev
Eduard Pisarev
IHIsmail Hosen
Ismail Hosen
OKOlga Kisil
Olga Kisil
SMSimon Matskeplishvili
Simon Matskeplishvili
FCFlorence Le Calvez-Kelm
Florence Le Calvez-Kelm
This review summarizes state-of-the-art knowledge in early-generation and novel urine biomarkers targeting the telomerase pathway for the detection and follow-up of bladder cancer (BC). The limitations of the assays detecting telomerase reactivation are discussed and the potential of transcription-activating mutations in the promoter of the TERT gene detected in the urine as promising simple non-invasive BC biomarkers is highlighted. Studies have shown good sensitivity and specificity of the urinary TERT promoter mutations in case-control studies and, more recently, in a pilot prospective cohort study, where the marker was detected up to 10 years prior to clinical diagnosis. However, large prospective cohort studies and intervention studies are required to fully validate their robustness and assess their clinical utility. Furthermore, it may be interesting to evaluate whether the clinical performance of urinary TERT promoter mutations could increase when combined with other simple urinary biomarkers. Finally, different approaches for assessment of TERT promoter mutations in urine samples are presented together with technical challenges, thus highlighting the need of careful technological validation and standardization of laboratory methods prior to translation into clinical practice.

8 February 2023 in Biomedicines
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Mark JainMark Jain
Mark Jain
ATAlexander Tivtikyan
Alexander Tivtikyan
DKDavid Kamalov
David Kamalov
SASavva Avdonin
Savva Avdonin
TRTagir Rakhmatullin
Tagir Rakhmatullin
AKArmais Kamalov
Armais Kamalov
Recent whole-genome sequencing studies identified two novel recurrent mutations in the enhancer region of GPR126 in urothelial bladder cancer (UBC) tumor samples. This mutational hotspot is the second most common after the TERT promoter in UBC. The aim of the study was to develop a digital droplet PCR screening assay for the simultaneous detection of GPR126 mutations in a single tube. Its performance combined with TERT promoter mutation analysis was evaluated in urine of healthy volunteers (n = 50) and patients with cystitis (n = 22) and UBC (n = 70). The developed assay was validated using DNA constructs carrying the studied variants. None of the mutations were detected in control and cystitis group samples. GPR126 mutations were observed in the urine of 25/70 UBC patients (area under the ROC curve (AUC) of 0.679; mutant allele fraction (MAF) of 21.61 [8.30–44.52] %); TERT mutations–in 40/70 (AUC of 0.786; MAF = 28.29 [19.03–38.08] %); ≥1 mutation–in 47/70 (AUC of 0.836)). The simultaneous presence of GPR126 and TERT mutations was observed in 18/70 cases, with no difference in MAFs for the paired samples (31.96 [14.78–47.49] % vs. 27.13 [17.00–37.62] %, p = 0.349, respectively). The combined analysis of these common non-coding mutations in urine allows the sensitive and non-invasive detection of UBC.

24 December 2025 in Diagnostics
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Mark JainMark Jain
Mark Jain
ATAlexander Tivtikyan
Alexander Tivtikyan
DKDmitry Kislyakov
Dmitry Kislyakov
TRTagir Rakhmatullin
Tagir Rakhmatullin
DKDavid Kamalov
David Kamalov
AKArmais Kamalov
Armais Kamalov
Background: Urothelial bladder carcinoma (UBC) is a disease that lacks robust non-invasive laboratory biomarkers. Recently, urine liquid biopsy has emerged as a promising tool for diagnosis and surveillance of patients with these tumors. The aim of this study was to evaluate the diagnostic potential of a urinary tumor DNA detection panel, which included eight common point mutations in TERT, GPR126, FGFR3, and PIK3CA genes, in UBC. Methods: The study included patients with histologically confirmed UBC (n = 88) and patients with cystitis, bladder leiomyomas, or other non-malignant conditions (control group; n = 72). DNA was extracted from whole urine specimens. ddPCR analysis was performed using the Bio-Rad QX200 AutoDG ddPCR system. Results: Urinary tumor DNA detection panel demonstrated a sensitivity of 78.4% and a specificity of 100% (AUC−ROC = 0.892). Detection rates for the analyzed mutations were the following: 54.5%, 37.5%, 28.4%, and 38.6% for TERT, GPR126, FGFR3, and PIK3CA, respectively. Pairwise comparisons of mutant allele fractions (MAFs) for samples simultaneously positive for ≥2 mutations revealed an absence of significant differences (p > 0.05), except for the pair of FGFR3 vs. PIK3CA (p = 0.03). MAFs were not associated with any clinical and demographic features (p > 0.05), with the only exception being the tumor size: patients with tumors larger than 2.16 cm3 had higher MAFs than the rest (23.4 [1.8; 46.3] vs. 1.6 [0; 24.6] %, respectively, p = 0.02). Conclusions: Upon further validation, the presented tumor DNA detection panel for ddPCR might become a useful tool for diagnostic purposes in UBC.

1 October 2022 in Urology Herald
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ASA. V. Savilov
A. V. Savilov
Mark JainMark Jain
Mark Jain
DAD. M. Anokhin
D. M. Anokhin
MKM. E. Kotsepuga
M. E. Kotsepuga
ATAlexander Tivtikyan
Alexander Tivtikyan
МДМ. Джайн
М. Джайн
Introduction. Urolithiasis is a polyethylological disease of the urinary system. Epidemiological data on urolithiasis is disappointing: over the past 30 years, the number of patients with urolithiasis has increased by 48.57%, and the mortality rate has increased by 17.12%. Single nucleotide polymorphisms in various genes can influence the risk of development and recurrence of this disease. Early diagnosis of a patient's genetic predisposition to primary or recurrent urolithiasis is important for the effective prevention of urolithiasis.Objective. To explore the association of SNP (Single Nucleotide Polymorphism) rs3134057 (TNFRS11B), rs851982 (ESR1), rs1540339 (VDR), rs2202127 (CASR), rs526906 (KL) with the development of recurrent urolithiasis.Materials and methods. The observed group consisted of 96 patients with a single-sided ureteral stone, of whom 45 had recurrent urolithiasis; the control group consisted of 51 volunteers. Venous blood samples were collected from all participants, DNA was extracted from the blood and analyzed for each SNP studied by real-time polymerase chain reaction. We analyze the data obtained on genotype and presence or absence of urolithiasis in the participants using a binomial logistic regression model.Results. An association was found between the presence of SNP rs3134057 in the TNFRS11B gene (odds ratio (OR), 1.92; confidence interval (CI): 1.05-3.52; p = 0.031) and the development of recurrent urolithiasis.Conclusion. The association of rs3134057 with urolithiasis relapse leads us to investigating the effect of this SNP on serum osteoprotegerin levels, a product of the TNFRS11B gene.

7 April 2023 in Urology Herald
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MCM. E. Chaliy
M. E. Chaliy
EAE. V. Afanasyevskaya
E. V. Afanasyevskaya
AAA. S. Amirkhanyan
A. S. Amirkhanyan
ASA. A. Strigunov
A. A. Strigunov
AKA. M. Kadysheva
A. M. Kadysheva
AKArmais Kamalov
Armais Kamalov
Introduction. Early diagnosis of cancer is one of the most important international strategies. Malignant and healthy tissues differ in the interaction with electromagnetic waves. Pilot studies show a potential perspective for non-invasive analysis of electromagnetic anisotropy in biological tissues.Objective. To assess the diagnostic importance of the electromagnetic detection of prostate cancer (PCa) within the prospective study.Materials & methods. One hundred and twenty-four patients were included to undergo a prostate biopsy, transurethral prostate resection, or radical prostatectomy. The investigators did not have information on their clinical details. Research technique: the probe was applied to the perineal region, turning it in three planes. A reduction of the 465 MHz band below a threshold was fixed and was considered suspect for PCa. The results of electromagnetic evaluation were compared with the findings of a pathomorphological study after biopsy or surgery.Results. Fourty-seven true-positive and 21 true-negative results were detected, 20 false-negative and 46 false-positive (follow-up group as potentially true-positive group). The overall sensitivity was 82%, specificity – 31%. The positive and negative predictive values were 73% and 62%, respectively. The accuracy of the method was 54%.Conclusion. Early PCa stage could be a reason for many false-positive results and low specificity, as a result. PCa detection is significantly reduced with lesions less than 3 mm, therefore patients with false-positive results were placed in the follow-up group. Patients’ examination with the TRIMprob TM («Galileo Avionica» SpA, Torino, Italy) could increase the early PCa detection at the screening. The research is currently ongoing.

5 October 2023 in Urology Herald
Verified
Journal Article
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ASA. V. Savilov
A. V. Savilov
Mark JainMark Jain
Mark Jain
ATAlexander Tivtikyan
Alexander Tivtikyan
MKM. E. Kotsepuga
M. E. Kotsepuga
DAD. M. Anokhin
D. M. Anokhin
МДМ. Джайн
М. Джайн
Introduction.In our earlier research on the role of genetic factors in the development of recurrent urolithiasis, a significant relationship was found between the presence of single-nucleotide polymorphism rs3134057 in the osteoprotegerin (OPG) gene and the development of this disease. The above-mentioned single-nucleotide polymorphism is intronic, therefore, it is unable to involve the structure and functions of the OPG but to affect its expression. Thus, the study of serum OPG level may have diagnostic significance in recurrent urolithiasis.Objective.To study the relationship of serum OPG level with the presence of recurrent urolithiasis, as well as the effect of single nucleotide polymorphism rs3134057 on the OPG level.Materials & methods.One hundred and fifteen volunteers were included in the study from January 2021 to January 2022. Of the 115 participants, 45 (main group #1) were diagnosed with recurrent urolithiasis and localisation of the main stone in one of the ureters, 28 participants (main group #2) had previously suffered a single episode of acute renal colic followed by surgical treatment or stone self-discharge and were stone-free at the time of the study. Forty-two control group respondents were free of urolithiasis, including family history of urolithiasis. The serum OPG levels was determined by enzyme immunoassay using the Human OPG ELISA kit ab100617 ("Abcam plc", Cambridge, UK) according to the manufacturer's advice.Results.The analysis revealed that the serum OPG levels were significantly higher in the main group #1 than in the control group (median: 9.02 vs. 3.635, p = 0.012). When analyzing the relationship between the concentration of OPG in serum and the AA + AG genotype versus GG according to rs3134057 of the OPG gene, no statistically significant difference was found (p > 0.05). The same result was obtained when comparing groups with AA vs. AG vs. GG genotypes (p > 0.05).Conclusion.The present study showed that an increased serum OPG level in patients with recurrent urolithiasis may indicate the presence of a relapse of the disease. Further study in large samples will finally confirm the significance of OPG as a marker of relapse, including in genetically determined forms.