Molecular characterization of equine thymidine kinase 1 and preliminary evaluation of its suitability as a serum biomarker for equine lymphoma

Abstract Background Thymidine kinase 1 (TK1) plays a key role in the synthesis of deoxythymidine triphosphate (dTTP) and is thus important for DNA replication and cell proliferation. The expression of TK1 is highest during S-phase, and it is rapidly degraded after mitosis. In cancer cells, TK1 is upregulated, resulting in leakage of excess TK1 into the blood. Consequently, serum TK1 has been used as a diagnostic and prognostic cancer biomarker, mainly in human medicine. The aims of this work were to characterize equine TK1 and to evaluate its suitability as a serum biomarker for equine lymphoma. Results Equine TK1 was cloned, expressed in E. coli and affinity purified. The purified recombinant horse TK1 showed broad substrate specificity, phosphorylating pyrimidine deoxyribo- and ribonucleosides and, to some extent, purine deoxynucleosides, including anticancer and antiviral nucleoside analogues. ATP was the preferred phosphate donor. Serum TK1 activity was measured in samples collected from horses with confirmed or suspected lymphoma and control horses with and without concurrent diseases. Serum TK1 activity levels were significantly higher in horses with lymphoma (p < 0.0005) and suspected lymphoma (p < 0.02) and in tumour-free groups with diverse diseases (p < 0.03) than in controls without concurrent diseases. There was a significant difference between the lymphoma group and the tumour-free group with diverse diseases (p < 0.0006). Furthermore, receiver operating characteristic analysis revealed a sensitivity of 0.86, a specificity of 0.95 and an AUC (area under the curve) of 0.92 compared to the controls without concurrent diseases, with a sensitivity of 0.97, a specificity of 0.71 and an AUC of 0.88 when compared with the tumour-free group with diverse diseases. Conclusion Equine TK1 showed high specific activity and broader substrate specificity than human TK1. Anticancer and antiviral thymidine analogues were efficiently phosphorylated by horse TK1, suggesting that these analogues might be good candidates for chemotherapy in horses. Serum TK1 activity was significantly higher in horses with lymphoma than in controls. ROC analysis indicated that serum TK1 could serve as a promising cancer biomarker in horses.

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Application of Serum Thymidine Kinase-1 in Cancer Risk Detection in Healthy Population

Nanoscience and Nanotechnology Letters ◽

10.1166/nnl.2019.3058 ◽

2019 ◽

Vol 11 (12) ◽

pp. 1734-1738

Author(s):

Jihong Xiao ◽

Yufei Zhao ◽

Chun Zhang

Keyword(s):

Cancer Risk ◽

Physical Examination ◽

Thymidine Kinase ◽

Normal Group ◽

Benign Tumors ◽

Thymidine Kinase 1 ◽

Male And Female ◽

Risk Detection ◽

Significant Difference ◽

Serum Thymidine Kinase 1

The purpose of this study was to evaluate the application of serum thymidine kinase 1 (STK1) in cancer risk detection in health general investigation. Using the method of dot-blot immunofluorescence enhancement, the data of STK1 of 12600 people were selected, and were carried out simultaneously with routine physical examination items. The results showed that the positive rate of STK1 (STK1> 2 pmol/L) was 2.10% with 2 pmol/L as the threshold, and the positive rates of male and female were 2.01% and 2.19%, respectively. There was no significant difference between male and female (χ2 = 0.46, P > 0.05). Compared with other age groups, both male and female between 40–59 years old had the highest detection rate in the age group of STK1 elevation, and twelve cases of malignant tumors were detected in the group of STK1 elevation, accounting for 4.55%. Compared with the normal group, it has significant significance. In the cases of benign tumors/cell dysplasia, 2194 cases detected were in normal group (17.78%) and 120 cases were in elevated group (45.45%). There was significant difference between normal group and elevated group (χ2 = 74.44, P < 0.01). There was no significant difference between the normal group and the elevated group in inflammatory, viral, fatty liver disease, other diseases and no special clinical conditions (P > 0.05). In the screening of cancer risk of general health investigation, STK1 can be applied to truly evaluate the abnormal proliferation of cells in vivo, and to screen a variety of tumors. It is suitable for early cancer risk screening of physical examination population.

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Relationship between thymidine kinase 1 before radiotherapy and prognosis in breast cancer patients with diabetes

Bioscience Reports ◽

10.1042/bsr20192813 ◽

2020 ◽

Vol 40 (4) ◽

Author(s):

Zhiwu Wang ◽

Wei Zhang ◽

Bingjie Huo ◽

Liang Dong ◽

Jing Zhang

Keyword(s):

Breast Cancer ◽

Thymidine Kinase ◽

Cancer Patients ◽

Poor Prognosis ◽

Univariate Analysis ◽

Clinical Parameters ◽

Breast Cancer Patients ◽

Thymidine Kinase 1 ◽

Node Number ◽

Significant Difference

Abstract In a retrospective study design, we explored the relationship between serum thymidine kinase 1 (TK1) concentration before radiotherapy and clinical parameters and evaluated the prognostic value of serum TK1 concentration before radiotherapy in breast cancer patients with type 2 diabetes mellitus. The present study finally consisted of 428 breast cancer patients with a mean age of 53.0 years. Compared with low TK1 group, the high TK1 group tended to have larger tumor size (P=0.011) and had more lymph node number (P=0.021). Significant differences were also observed in clinical stages I, II and III (P=0.000). There was no significant difference between TK1 and other clinical parameters. For disease-free survival (DFS), the univariate analysis indicated that the high TK1 increased the risk of poor prognosis (HR = 2.38, 95% CI: 1.64–4.23, P=0.000). The Kaplan–Meier curve indicated the high TK1 group was poorer than that in the low TK1 group (P=0.002). For the overall survival (OS), similar results were found that the high TK1 was related to poor OS (HR = 1.89, 95% CI: 1.34–3.67, P=0.000). The multivariate Cox regression indicated that the TK1 was still associated with DFS (HR = 1.83, 95% CI: 1.22–3.17, P=0.001) and OS (HR = 1.63, 95% CI: 1.19–2.08, P=0.006). The high pretreatment serum TK1 levels in breast cancer patients were associated with poor OS and DFS. TK1 could be a potential predictive factor in differential diagnosis of poor prognosis from all patients.

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Feline thymidine kinase 1: molecular characterization and evaluation of its serum form as a diagnostic biomarker

BMC Veterinary Research ◽

10.1186/s12917-021-03030-5 ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Liya Wang ◽

Hanan Sharif ◽

Sara Saellström ◽

Henrik Rönnberg ◽

Staffan Eriksson

Keyword(s):

Thymidine Kinase ◽

Inflammatory Disease ◽

High Efficiency ◽

Specific Activity ◽

High Specific Activity ◽

Nucleoside Analogs ◽

Response To Treatment ◽

Malignant Diseases ◽

Diagnostic Biomarker ◽

Thymidine Kinase 1

Abstract Background Thymidine kinase 1 (TK1) catalyzes the initial phosphorylation of thymidine in the salvage pathway synthesis of dTTP, an essential building block of DNA. TK1 is a cytosolic enzyme with its highest level during the S-phase of the cell cycle. In cancer cells TK1 is upregulated and excess TK1 is leaked into the blood. Therefore, serum TK1 has been used as biomarker for cancer diagnosis and prognosis in human medicine. Feline TK1 shows high sequence similarity to TK1 from other species. The aim of this study was to characterize feline TK1 and evaluate if serum TK1 can be used as a diagnostic biomarker. Results Feline TK1 was cloned, expressed and affinity purified. The purified feline TK1 phosphorylated not only pyrimidine deoxyribonucleosides but also pyrimidine ribonucleosides and to some extent purine deoxynucleosides. A number of anticancer and antiviral nucleoside analogs also served as substrates with fairly high efficiency. ATP and dATP were the preferred phosphate donor. Serum TK1 activity in felines with malignant diseases was significantly higher than that in healthy individuals. ROC analysis revealed an area under the curve (AUC) of 0.98 with a sensitivity of 0.83 and a specificity of 0.95 for felines with lymphoma. Serum TK1 activity in felines with IBD or inflammatory disease was within the same range as healthy ones. Furthermore, in felines with lymphoma serum TK1 activity returned to normal levels in response to treatment. Conclusion Feline TK1 has high specific activity and a broader substrate specificity in comparison with TK1 from other species. Serum TK1 activity in felines with malignant diseases is significantly higher than that in normal felines and in felines with inflammatory diseases. These results suggest that serum TK1 may be a promising biomarker for the diagnosis and monitoring of malignant diseases and for the differential diagnosis of certain inflammatory disease.

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Prognostic role of serum thymidine kinase 1 kinetics during neoadjuvant chemotherapy for early breast cancer

ESMO Open ◽

10.1016/j.esmoop.2021.100076 ◽

2021 ◽

Vol 6 (2) ◽

pp. 100076

Author(s):

A. Matikas ◽

K. Wang ◽

E. Lagoudaki ◽

B. Acs ◽

I. Zerdes ◽

...

Keyword(s):

Breast Cancer ◽

Neoadjuvant Chemotherapy ◽

Thymidine Kinase ◽

Early Breast Cancer ◽

Prognostic Role ◽

Thymidine Kinase 1 ◽

Serum Thymidine Kinase 1

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Comparison of Simulation-Based versus Cadaveric-Tissue-Based Ocular Trauma Training on Novice Ophthalmologists: Repair of Corneal Laceration Model

Journal of Academic Ophthalmology ◽

10.1055/s-0041-1725093 ◽

2021 ◽

Vol 13 (01) ◽

pp. e57-e65

Author(s):

Boonkit Purt ◽

Timothy Ducey ◽

Sean Sykes ◽

Joseph F. Pasternak ◽

Denise S. Ryan ◽

...

Keyword(s):

Primary Outcome ◽

Wound Closure ◽

Ocular Trauma ◽

Controlled Trial ◽

Preliminary Evaluation ◽

Skills Acquisition ◽

Visual Axis ◽

Significant Difference ◽

Skills Laboratory ◽

Corneal Laceration

Abstract Purpose The aim of this study was to evaluate whether the simulated tissue models may be used in place of animal-based model for corneal laceration repair for surgical skills acquisition. Design Prospective randomized controlled trial. Participants Seventy-nine military and civilian 2nd- and 3rd-year ophthalmology residents and 16 staff ophthalmologists participating in the Tri-Service Ocular Trauma Skills Laboratory at the Uniformed Services University (Bethesda, MD). Methods Resident ophthalmologists underwent preliminary evaluation of their ability to close a 5-mm linear, full-thickness corneal laceration involving the visual axis. They then were randomized to undergo 90 to 120 minutes of either simulator-based (SIM) or swine cadaveric-tissue-based (CADAVER) corneal laceration repair. The same evaluation was performed post training. On a more limited basis, the study was repeated for attending ophthalmologists to act as a pilot for future analysis and test efficacy for “refresher” training. Main Outcome Measures Successful wound closure with secondary outcomes of suture length, tension, depth, and orientation, as graded by attending ophthalmologists. Results No significant difference in CADAVER versus SIM groups in the primary outcome of watertight wound closure of the corneal laceration. CADAVER group performed better than SIM group for certain metrics (suture depth, p = 0.009; length, p = 0.003; and tension, p = 0.043) that are associated with poor wound closure and increased amount of induced corneal astigmatism. For attending ophthalmologists, six of the eight in each group (SIM and CADAVER) retained or improved their skills. Conclusions For resident ophthalmologists, SIM training is sufficient for achieving the primary outcome of watertight wound closure. However, CADAVER training is superior for wound metrics for the ideal closure. For attending ophthalmologists, SIM training may be useful for retention of skills.

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Clinicopathological correlation of pre-biopsy quantitative PSMA uptake in patients with persistently raised serum PSA: initial experience in 74 patients with simultaneous 68-Ga PSMA PET/MRI

Journal of Clinical Urology ◽

10.1177/2051415820956406 ◽

2020 ◽

pp. 205141582095640

Author(s):

Malik A Rouf ◽

Rajesh Taneja ◽

Venkatesh Kumar

Keyword(s):

Specific Antigen ◽

Digital Rectal Examination ◽

Whole Body ◽

Characteristic Analysis ◽

Positron Emission ◽

Psma Pet ◽

Significant Difference ◽

Magnetic Resonance Imaging Mri ◽

Normal Urine ◽

Delayed Phase

Objective: To analyze 68-Ga prostate-specific membrane antigen (PSMA) uptake pattern of the prostate and its correlation with prostate-specific antigen (PSA), digital rectal examination (DRE), and Gleason’s score in the diagnosis of carcinoma of the prostate (CaP). Methods: This was a retrospective study conducted between June 2015 and August 2017. Patients who had undergone whole body 68-Ga PSMA HBED-CC simultaneous positron emission tomography (PET) or magnetic resonance imaging (MRI) for the diagnosis or staging of CaP were eligible. Patients who presented with persistently raised serum PSA (>4 ng/mL) and normal urine routine and negative culture were included in the study. Results: A total of 74 patients were included in the study. Significant positive correlation was observed between PSMA delayed uptake with the Prostate Imaging Reporting and Data System (PI-RADS) score ( p<0.001, ρ=0.750), PSA level ( p<0.001, ρ=0.414), DRE ( p<0.002, ρ=0.400), and Gleason’s score ( p<0.300, ρ=0.02). There was a significant difference between early and delayed phase of PSMA uptake in malignant prostatic lesions ( p<0.001). Delayed phase of PSMA uptake was able to characterize prostate lesions with an area under curve (AUC) of 0.91. Combined receiver operating characteristic analysis of PI-RADS score derived from multiparametric MRI and differential PSMA uptake to characterize prostatic lesions improved AUC to 0.94. Conclusion: Results demonstrated that the correlation with clinicopathological features (PSA, DRE, and Gleason’s score) could be used in prognostication of prostatic lesion along with PSMA PET/MRI.

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Comparison of ocular surface assessment and adherence between preserved and preservative-free latanoprost in glaucoma: a parallel-grouped randomized trial

Scientific Reports ◽

10.1038/s41598-021-94574-x ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Dai Woo Kim ◽

Jonghoon Shin ◽

Chang Kyu Lee ◽

Myungjin Kim ◽

Sohyeon Lee ◽

...

Keyword(s):

Free Group ◽

Ocular Surface ◽

Open Angle Glaucoma ◽

Drug Tolerance ◽

Adherence Rate ◽

Eye Drops ◽

Ocular Surface Disease Index ◽

Significant Difference ◽

Surface Assessment ◽

Preservative Free

AbstractGiven that nonadherence is related to subject characteristics and drug tolerance and preserved eye drops tend to be more intolerable than preservative-free ones, we conducted a phase 4, parallel-grouped, investigator-blind, active-control, randomized, multicenter study. A total of 51 patients with intraocular pressure (IOP) ≥ 15 mmHg diagnosed with open-angle glaucoma or ocular hypertension were randomly assigned to the preserved latanoprost group (n = 26) and the preservative-free latanoprost group (n = 25). The efficacy variables were corneal/conjunctival staining grade, Ocular Surface Disease Index (OSDI), adherence at 12 weeks after the first administration; corneal/conjunctival staining grade at 4 weeks; and IOP, tear break-up time (TBUT), and hyperemia score at 4 and 12 weeks. The safety variables included visual acuity and drug tolerance questionnaire results. There was no statistically significant difference in corneal/conjunctival staining grade, OSDI, or TBUT between the groups at 4 and 12 weeks. However, the adherence rate was higher and the hyperemia score was lower in the preservative-free group than in the preserved group. The severity and duration of stinging/burning sensation were lower in the preservative-free group than in the preserved group. Overall, preservative-free latanoprost showed better ocular tolerance assessed by hyperemia scores and stinging/burning symptoms following higher adherence than preserved latanoprost.

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