Determination of Total Antioxidant Capacity in Patients with Bladder Cancer and its Correlation with the Results of Pathology

Abstract

Introduction: 

The accumulative consequence of all antioxidants that exist in the blood and body fluids is called total antioxidant capacity (TAOC). The major objective of this investigation is to determine the correlation between TAOC and pathology results in patients with non-muscle invasive bladder cancer (NMIBC).

Materials and Methods: 

Based on the cross-sectional method, 35 patients with NMIBC and 35 controls (healthy characters) were studied. Biochemical and haematological variables were achieved and noted for each individual. Two blood samples (n = 5 ml) from each patient were obtained and analysed using Trolox standard immunoassay kit. Three groups were made according to the pathology results. The significance level was set at P ≤ 0.05.

Results: 

There were not any significant differences (P = 0.12) between the mean age of patients and controls (60.7 vs. 59.5 years old) correspondingly. The mean value of TAOC (μmol/L) was significantly (P = 0.005) lower in patients when compared to controls (24.5 μmol/L vs. 94 μmol/L), respectively. In patients with NMIBC, sodium, magnesium, calcium, albumin, MCH, MCHC, VHCO3, haemoglobin, haematocrit and lymph were lower than the normal range. Blood sugar, creatinine, prothrombin time and white blood cells were higher than the normal range. The mean TAOC was as follows: papillary cell carcinoma (26.3 μmol/L), radical cystectomy (19 μmol/L) and high-grade bladder cancer (15.9 μmol/L).

Conclusion: 

As deregulation of reactive oxygen species and antioxidant defence is two important components, in this study, there was high variation in TAOC according to pathology results. Combing individual TAOC and pathology results might be able to contribute to the advanced management of NMIBC. Further studies in this direction seem to be advantageous.

INTRODUCTION

Bladder cancer (BC) is the most common urinary tract cancer worldwide and in Iran. Recent epidemiological studies confirmed a period prevalence of 33.2/100,000 in Isfahan.^[1–3] The vast majority of BC diagnoses involved non-muscle invasive bladder cancer (NMIBC), which represents a spectrum of diseases with a variable clinical course notable for significant risk of recurrence. In fact, those tumours that are staged as Ta, T1 and carcinoma in situ (CIS) are grouped under the heading of NMIBC. Cystoscopy and histological evaluation of tissue obtained through transurethral resection of the bladder for papillary tumours could make the diagnosis. The risk of progression may be estimated for individual patients using the 2021 EAU scoring model.^[4,5] Reduction-oxidation disorders are characterised by both initiation and progression in BC. Oxidative stress that results from the overproduction of carcinogenic xenobiotic and nitrosative stress on pathways of signalling and transcription factors revealed importance in BC. The activity of transcription factors, hypoxia-inducible factor and mitogen-activated protein kinase designate a role for oxidative stress and its involvement in bladder carcinogenesis. Nitrosative damage due to the constant level of reactive forms of nitrogen during the inflammation process in patients is typical in BC. In fact, the antioxidant status of biological samples and total antioxidant capacity (TAOC) could be used for the estimation of the antioxidant reaction against the free radicals BC.^[6–9] TAOC as an analyte could be used to assess the antioxidant status of biological samples and can evaluate the antioxidant response against the free radicals produced in disease conditions.^[10] In fact, TAOC as a biomarker is defined as the moles of oxidants neutralised by 1 L of solution that measures the antioxidant potential of body fluids.^[11] Another published article showed that glutathione S-transferase, glutathione reductase and superoxide dismutase were lower in patients with BC compared to the control group. Ionising radiation and some environmental agents, chemical substances, alcohol, food, tobacco, chemotherapeutical agents and infectious agents contribute to the production of reactive oxygen species (ROS).^[12,13] Indeed, to drive tumourigenesis and cancer progression, hypomethylation of long interspersed nuclear element-1 is necessary.^[14] A rise in ROS as well as 8-OHdG levels, accompanied by significant in TAOC and GSH, showed its importance in other cancers.^[15] Although 85% of patients present with less aggressive NMIBC, they have a high risk of recurrence and those with unfavourable characteristics, such as multifocal disease high-grade tumours, with or without concomitant CIS, are at particular risk of disease progression. Several reviews described the various assays commonly used for the measurement of TAOC,^[5–8] and a good correlation between the results obtained with different methods was found. The publication reported that saliva and urine could represent non-invasive diagnostic fluids for various pathological conditions. To assess antioxidant status, its in vivo regeneration should be considered.^[9,16] Therefore, this study aimed to investigate the correlation between TAOC and pathology results in patients with BC.

MATERIALS AND METHODS

The study was approved by the Isfahan Deputy of the Research Committee through the Ethics Committee Code Number 297103.

The sample size was considered based on this formula;^[3]

n = Sample size, Zα = Level of confidence according to the standard normal distribution (for a level of confidence of 95%, Z = 1.96, for a level of confidence of 99%, Z = 2.575), P = Estimated proportion of the population that presents the characteristic and d = Tolerated margin of error.

The study involved 35 patients with biopsy-confirmed BC and 35 healthy age-matched controls. There was no other disease or malignancies. The pathology results (n = 35) were obtained from the hospital pathology section. All biochemical and haematological variables were obtained for each individual and categorised as lower and above the normal range. Blood samples (n = 5 ml) were taken from patients and analysed by Trolax standard immunoassay kit.^{[1–3,11–13]} The obtained data were analysed by the Chi-square and independent sample t-tests using the Statistical Package for the Social Sciences software (IBM Corp. (2013) IBM SPSS Statistics for Windows, Version 22.0. IBM Corp., Armonk, NY.). The significance level was set at P ≤ 0.05.

RESULTS

Patients with BC (n = 35) and controls (n = 35) comprised 10 females and 25 males were entered into the study. Age (mean ± standard deviation [SD]; minimum–maximum) of the patients versus healthy controls was (60.7 ± 13.4; 30–89) versus (59.5 ± 13.7; 29–88) years (P = 0.12) correspondingly. The mean ± SD (range) value of TAOC in patients versus healthy controls was 24.5 ± 28.8 (0.5–95) versus 94.0 ± 15.5 (65–124) μmol/L (P = 0.005). Study of biochemical and haematological variables amongst the total population studied showed that sodium (31%), magnesium (14%), calcium (23%), albumin (31%), MCH (23%), MCHC (37%), VHCO3 (34%), haemoglobin (60%), haematocrit (60%) and lymph (60%) were lower than the normal range. Blood sugar (11%), creatinine (23%), prothrombin time (29%), international normalised ratio (29%) and white blood cell (43%) were higher than the normal range. Urine colour in 11.4%, 3% and 9% of population was deep yellow, light brown and deep brown. Amongst the total population studied, group 3 was comprised three patients with radical cystectomy. Pathology confirmed papillary cell carcinoma (n = 28; group 1) and high-grade BC (n = 4; group 2). Comparison of group 1 versus group 2 confirmed significant differences in; blood sugar (P = 0.06), PCO2 (P = 0.01), HC03 (P = 0.06), VBB (P = 0.06), VPO2 (P = 0.04) and RBC (P = 0.06). Comparison of group 1 versus group 3 confirmed; albumin (P = 0.03), PCO2 (P = 0.00), HC03 (P = 0.01), VBB (P = 0.00), VPO2 (P = 0.06), PO2SAT (P = 0.06) and PT (P = 0.02). Comparison of group 2 versus group 3 confirmed; albumin (P = 0.02) and VBB (P = 0.05). According to pathology results shown in Figure 1, the mean TAOC in group 1 versus group 2 versus group 3 was 26.3 versus 15.9 versus 19 μmol/L.

Figure 1: The mean TAOC in three groups of patients according to the pathology results. TAOC: Total antioxidant capacity.

DISCUSSION

Cancer of the bladder, also known as urological cancer or urinary BC, is the 10^th-most common cancer^[17] and accounts for 3% of global cancer diagnoses.^[18] Transitional cell carcinoma of the urinary bladder has a worldwide annual incidence of over 350,000 new cases and 145,000 deaths.^[9] A total of 90% of BC diagnoses are made in those 55 years of age and older. BC is more common in men than women. The average 5-year survival for those with metastatic disease is a miserable 5%.^[18] Increased generation of ROS could cause oncogenic transformation in addition to changes in metabolic activity. Consequently, due to the increase in ROS, there is stimulation of cellular proliferation, promotion of mutations and genetic instability.^[16] In disease conditions, free radical damage reported for the assessment of oxidative stress in biological systems. Regarding the measurement of ROS within the body, the inconsequence of accessible methods confirms the fact that no ideal method is available. Accordingly, there is a need for a single test that could reflect an available practical performance. Therefore, in this study, the possible correlation between TAOC and pathology state was investigated.

In agreement with a previously published article,^[3] TAOC in healthy controls was higher than in patients with BC (94 vs. 24.5 μmol/L). In fact, when there is a physiological condition, then any damage caused by free radicals could be prevented by the components that could be either enzymatic or non-enzymatic. Essentially, antioxidants could suppress the proliferation and apoptosis of cells within the human body.

In agreement with previously published articles, the most incidence of BC has occurred around the age of 60 years.^[1–3] In this study, serum samples were obtained from the patients and measured by Trolax-TAOC kit based on immunoassay.^[3] However, the results of TAOC in three groups of patients studied here were significantly low, but there was high dissimilarity in different groups according to the pathology results. It is well known that deregulation of ROS and antioxidant defence is two important components of the human body. Therefore, in those with pathology reported as papillary cell carcinoma, TAOC was higher than in those with high-grade BC. In those with radical cystectomy, it was between groups 1 and 2. This is in agreement with the previous publication that reported disruption of redox signalling and physiological function in patients with BC could be associated with pathology state regarding papillary cell carcinoma and high-grade BC as in the former lower amount of TAOC was obtained.^[3] The measurement of TAOC in serum of patients with NMIBC was established before. However, the issue related to economic measurement on a large scale could be a matter of concern for future studies.^[19–29]

CONCLUSION

We reported the correlation between TAOC in patients with BC and pathology results. However, the results of TAOC in patients with BC were lower than normal controls, and there was a correlation with the stage of pathology. In those with papillary cell carcinoma, the result of TAOC was higher than in those with high-grade BC. As for advanced management of patients with BC, further determination and clarification for a more sensitive detection method in a larger number of patients and its exact role in different pathologic stages are recommended.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.