Serum triiodothyronine is increased in men with prostate cancer and benign prostatic hyperplasia

Genetically predicted alterations in thyroid function are associated with the risk of benign prostatic disease

Background

Benign prostatic diseases (BPDs), such as benign prostate hyperplasia (BPH) and prostatitis, harm the quality of life of affected patients. However, observational studies exploring the association between thyroid function and BPDs have hitherto yielded inconsistent results. In this study, we explored whether there is a causal genetic association between them using Mendelian randomization (MR) analysis.

Methods

We used publicly available summary statistics from the Thyroidomics Consortium and 23andMe on thyrotropin (TSH; 54,288 participants), thyroxine [free tetraiodothyronine (FT4); 49,269 participants], subclinical hypothyroidism (3,440 cases and 49,983 controls), overt hypothyroidism (8,000 cases and 117,000 controls), and subclinical hyperthyroidism (1,840 cases and 49,983 controls) to screen for instrumental variables of thyroid function. Results for BPD such as prostatic hyperplasia (13,118 cases and 72,799 controls) and prostatitis (1,859 cases and 72,799 controls) were obtained from the FinnGen study. The causal relationship between thyroid function and BPD was primarily assessed using MR with an inverse variance weighted approach. In addition, sensitivity analyses were performed to test the robustness of the results.

Results

We found that TSH [OR (95% CI) = 0.912(0.845-0.984), p =1.8 x 10^-2], subclinical hypothyroidism [OR (95% CI) = 0.864(0.810-0.922), p =1.04 x 10^-5], and overt hypothyroidism [OR (95% CI) = 0.885 (0.831-0. 944), p =2 x 10^-4] had a significant effect on genetic susceptibility to BPH, unlike hyperthyroidism [OR (95% CI) = 1.049(0.990-1.111), p =1.05 x 10^-1] and FT4 [OR (95% CI) = 0.979(0.857-1.119), p = 7.59 x 10^-1] had no effect. We also found that TSH [OR (95% CI) =0.823(0.700-0.967), p = 1.8 x 10^-2] and overt hypothyroidism [OR (95% CI) = 0.853(0.730-0.997), p = 4.6 x 10^-2] significantly influenced the prostatitis, whereas FT4 levels [OR (95% CI) = 1.141(0.901-1.444), p = 2.75 x 10^-1], subclinical hypothyroidism [OR (95% CI) =0. 897(0.784- 1.026), p = 1.12 x 10^-1], and hyperthyroidism [OR (95% CI) = 1.069(0.947-1.206), p = 2.79 x 10^-1] did not have a significant effect.

Conclusion

Overall, our study results suggest that hypothyroidism and TSH levels influence the risk of genetically predicted BPH and prostatitis, providing new insights into the causal relationship between thyroid function and BPD.

Aromatic amino acids play a harmonizing role in prostate cancer: A metabolomics-based cross-sectional study

BACKGROUND

Prostate cancer (PCa) is a common health problem worldwide. The rate of this disease is likely to grow by 2021. PCa is a heterogeneous disorder, and various biochemical factors contribute to the development of this disease. The metabolome is the complete set of metabolites in a cell or biological sample and represents the downstream end product of the omics. Hence, to model PCa by computational systems biology, a preliminary metabolomics-based study was used to compare the metabolome profile pattern between healthy and PCa men.

OBJECTIVE

This study was carried out to highlight energy metabolism modification and assist the prognosis and treatment of disease with unique biomarkers.

MATERIALS AND METHODS

In this cross-sectional research, 26 men diagnosed with stage-III PCa and 26 healthy men with normal PSA levels were enrolled. Urine was analyzed with proton nuclear magnetic resonance (1 H-NMR) spectroscopy, accompanied by the MetaboAnalyst web-based platform tool for metabolomics data analysis. Partial least squares regression discriminant analysis was applied to clarify the separation between the two groups. Outliers were documented and metabolites determined, followed by identifying biochemical pathways.

RESULTS

Our findings reveal that modifications in aromatic amino acid metabolism and some of their metabolites have a high potential for use as urinary PCa biomarkers. Tryptophan metabolism (p < 0.001), tyrosine metabolism (p < 0.001), phenylalanine, tyrosine and tryptophan biosynthesis (p < 0.001), phenylalanine metabolism (p = 0.01), ubiquinone and other terpenoid-quinone biosynthesis (p = 0.19), nitrogen metabolism (p = 0.21), and thiamine metabolism (p = 0.41) with Q2 (0.198) and R2 (0.583) were significantly altered.

CONCLUSION

The discriminated metabolites and their pathways play an essential role in PCa causes and harmony.

Endocrinology of the Aging Prostate: Current Concepts

Benign prostate hyperplasia (BPH), one of the most common diseases in older men, adversely affects quality-of-life due to the presence of low urinary tract symptoms (LUTS). Numerous data support the presence of an association between BPH-related LUTS (BPH-LUTS) and metabolic syndrome (MetS). Whether hormonal changes occurring in MetS play a role in the pathogenesis of BPH-LUTS is a debated issue. Therefore, this article aimed to systematically review the impact of hormonal changes that occur during aging on the prostate, including the role of sex hormones, insulin-like growth factor 1, thyroid hormones, and insulin. The possible explanatory mechanisms of the association between BPH-LUTS and MetS are also discussed. In particular, the presence of a male polycystic ovarian syndrome (PCOS)-equivalent may represent a possible hypothesis to support this link. Male PCOS-equivalent has been defined as an endocrine syndrome with a metabolic background, which predisposes to the development of type II diabetes mellitus, cardiovascular diseases, prostate cancer, BPH and prostatitis in old age. Its early identification would help prevent the onset of these long-term complications.

The induction of core pluripotency master regulators in cancers defines poor clinical outcomes and treatment resistance

Stem cell characteristics have been associated with treatment resistance and poor prognosis across many cancer types. The ability to induce and regulate the pathways that sustain these characteristic hallmarks of lethal cancers in a novel in vitro model would greatly enhance our understanding of cancer progression and treatment resistance. In this work, we present such a model, based simply on applying standard pluripotency/embryonic stem cell media alone. Core pluripotency stem cell master regulators (OCT4, SOX2 and NANOG) along with epithelial–mesenchymal transition (EMT) markers (Snail, Slug, vimentin and N-cadherin) were induced in human prostate, breast, lung, bladder, colorectal, and renal cancer cells. RNA sequencing revealed pathways activated by pluripotency inducing culture that were shared across all cancers examined. These pathways highlight a potential core mechanism of treatment resistance. With a focus on prostate cancer, the culture-based induction of core pluripotent stem cell regulators was shown to promote survival in castrate conditions—mimicking first line treatment resistance with hormonal therapies. This acquired phenotype was shown to be mediated through the upregulation of iodothyronine deiodinase DIO2, a critical modulator of the thyroid hormone signalling pathway. Subsequent inhibition of DIO2 was shown to supress expression of prostate specific antigen, the cardinal clinical biomarker of prostate cancer progression and highlighted a novel target for clinical translation in this otherwise fatal disease. This study identifies a new and widely accessible simple preclinical model to recreate and explore underpinning pathways of lethal disease and treatment resistance.

The Relationships between Thyroid Hormone Levels and Lower Urinary Tract Symptoms/Benign Prostatic Hyperplasia

PURPOSE

We examined the association between thyroid hormone and lower urinary tract symptoms (LUTS)/benign prostatic hyperplasia (BPH).

MATERIALS AND METHODS

A total of 5,708 middle aged men were included. LUTS/BPH were assessed using the international prostate symptom score (IPSS), total prostate volume (TPV), maximal flow rate (Qmax), and a full metabolic workup. Thyroid stimulating hormone (TSH) and free thyroxine (FT4) levels were measured using chemiluminescence immunoassay. We divided participants into quartiles based on their TSH and FT4 levels: first to fourth quartile (Q1-Q4).

RESULTS

There was a significant increase in the percentage of men with IPSS>7, Qmax<10 mL/s, and TPV≥30 mL with increase of FT4 quartile. The adjusted odds ratio (OR) for TPV≥30 mL and IPSS>7 were significantly different between FT4 quartile groups (ORs; [5-95 percentile interval], p; TPV≥30 mL, Q1: 0.000 [references]; Q2: 1.140 [0.911-1.361], p=0.291; Q3: 1.260 [1.030-1.541], p=0.025; Q4: 1.367 [1.122-1.665], p=0.002; IPSS>7: Q1: 0.000 [references]; Q2: 0.969 [0.836-1.123], p=0.677; Q3: 1.123 [0.965-1.308], p=0.133; Q4: 1.221 [1.049-1.420], p=0.010). In men with above median levels of testosterone, the FT4 correlated positively with TPV, even after adjusting for confounders. However, the FT4 was not correlated with TPV in men with below median levels of testosterone. TSH was not related to LUTS/BPH measurements.

CONCLUSIONS

TPV, IPSS, and Qmax were significantly related to FT4. TPV and IPSS were significantly and independently related to FT4. Additionally, the relationship between FT4 and TPV was distinct when testosterone levels are high.

Thyroid Hormones and Cancer: A Comprehensive Review of Preclinical and Clinical Studies

Thyroid hormones take major part in normal growth, development and metabolism. Over a century of research has supported a relationship between thyroid hormones and the pathophysiology of various cancer types. In vitro studies as well as research in animal models demonstrated an effect of the thyroid hormones T3 and T4 on cancer proliferation, apoptosis, invasiveness and angiogenesis. Thyroid hormones mediate their effects on the cancer cell through several non-genomic pathways including activation of the plasma membrane receptor integrin αvβ3. Furthermore, cancer development and progression are affected by dysregulation of local bioavailability of thyroid hormones. Case-control and population-based studies provide conflicting results regarding the association between thyroid hormones and cancer. However, a large body of evidence suggests that subclinical and clinical hyperthyroidism increase the risk of several solid malignancies while hypothyroidism may reduce aggressiveness or delay the onset of cancer. Additional support is provided from studies in which dysregulation of the thyroid hormone axis secondary to cancer treatment or thyroid hormone supplementation was shown to affect cancer outcomes. Recent preclinical and clinical studies in various cancer types have further shown promising outcomes following chemical reduction of thyroid hormones or inhibition or their binding to the integrin receptor. This review provides a comprehensive overview of the preclinical and clinical research conducted so far.

Hyperthyroidism is not a significant risk of benign prostatic hyperplasia: A nationwide population-based study

Benign prostatic hyperplasia (BPH) is a common disorder in the aging male population. Despite evidence that thyroid status impacts the prostate, the objective of this study was to examine whether patients with hyperthyroidism were at a greater risk for BPH.This study is a retrospective nationwide population-based cohort study of the Chinese population. Data for this study were retrieved from the Taiwan National Health Insurance Research Database (NHIRD). Overall, 1032 male patients aged 40 years or older with hyperthyroidism diagnosed between 2000 and 2006 were included in the hyperthyroidism group, and 4128 matched controls without hyperthyroidism were included in the non-hyperthyroidism group. Both groups were monitored until the end of 2011. A Cox proportional hazards regression model was used to compute and compare the risk of BPH between study participants with and those without hyperthyroidism.Patients with hyperthyroidism exhibited a greater incidence of BPH (18.51% vs 15.53%) than did the controls. Furthermore, the hazard ratio (HR) of the hyperthyroidism group was 1.24 times that of the control group [95% confidence interval (95% CI 1.05-1.46)] signifying that there is a significant 24% increase in the risk of BPH with the presence of hyperthyroidism. This increased risk of BPH with hyperthyroidism, however, failed to remain significant (adjusted HR = 1.11, 95% CI = 0.94-1.3) after adjusting for covariates of age (adjusted HR = 2.72, 95% CI = 2.32-3.2), diabetes (adjusted HR = 1.4, 95% CI = 1.17-1.68), hypertension (adjusted HR = 1.74, 95% CI = 1.49-2.03), hyperlipidemia (adjusted HR = 1.25, 95% CI = 1.03-1.53), neurogenic bladder, cystitis (adjusted HR = 1.23, 95% CI = 0.58-2.59), urethral stricture (adjusted HR = 2.01, 95% CI = 0.28-14.47), urethritis (adjusted HR = 1.52, 95% CI = 0.72-3.21), and urinary tract infection (adjusted HR = 1.77, 95% CI = 1.31-2.39).After adjustment for comorbidities and covariates, hyperthyroidism was not found to be a significant risk factor of BPH in our male study subjects. Further research is warranted to validate our results and elucidate the association of the pathophysiology of these 2 diseases.

Thyroid dysfunction, thyroid hormone replacement and colorectal cancer risk

BACKGROUND

Current screening guidelines for colorectal cancer (CRC) do not consider thyroid dysfunction as a risk factor for disease development. We sought to determine the risk of developing CRC in patients with thyroid dysfunction, with and without thyroid hormone replacement (THR).

METHODS

We conducted a nested case-control study using a large population-based medical records database from the United Kingdom. Study case patients were defined as those with any medical code of CRC. Subjects with familial colorectal cancer syndromes or inflammatory bowel disease (IBD) were excluded. For every case patient, four eligible control patients matched on age, sex, practice site, and duration of follow-up before index date were selected using incidence density sampling. Exposure was THR therapy before index date. We further divided the THR unexposed group into patients with hypothyroidism (TSH > 4 mg/dl), patients with hyperthyroidism (TSH < 0.4 mg/dl), and subjects without documented thyroid abnormality. The adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for CRC were estimated using conditional logistic regression. All statistical tests were two-sided.

RESULTS

We identified 20990 CRC patients and 82054 control patients. The adjusted odds ratio for CRC associated with THR was 0.88 (95% CI = 0.79 to 0.99, P = .03) and 0.68 (95% CI = 0.55 to 0.83, P < .001) for treatment initiated five to 10 years and more than 10 years before index date, respectively. This protective association increased with cumulative duration of therapy. In contrast, hyperthyroidism (adjusted OR = 1.21, 95% CI = 1.08 to 1.36, P = .001) or untreated hypothyroidism (adjusted OR = 1.16, 95% CI = 1.08 to 1.24, P < .001) were associated with increased risk of CRC.

CONCLUSION

Long-term THR is associated with a decreased risk of CRC. Hyperthyroidism and untreated hypothyroidism are associated with modestly elevated risk of CRC.

Circulating thyroxine, thyroid-stimulating hormone, and hypothyroid status and the risk of prostate cancer

BACKGROUND

Thyroid hormones may influence risk of cancer through their role in cell differentiation, growth, and metabolism. One study of circulating thyroid hormones supports this hypothesis with respect to prostate cancer. We undertook a prospective analysis of thyroid hormones and prostate cancer risk in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study.

METHODS

Within the ATBC Study, a randomized controlled trial of α-tocopherol and β-carotene supplements and cancer incidence in male smokers, 402 prostate cancer cases were sampled. Controls were matched 2:1 to cases on age and date of blood collection. Odds ratios (OR) and 95% confidence intervals (CI) of prostate cancer were estimated for quintiles of serum total and free thyroxine (T4), thyroid-stimulating hormone (TSH), thyroid-binding globulin (TBG), and by categories of thyroid status.

RESULTS

Men with serum higher TSH had a decreased risk of prostate cancer compared to men with lower TSH (Q5 vs. Q1-4: OR = 0.70, 95% CI: 0.51-0.97, p = 0.03). When the T4 and TSH measurements were combined to define men as hypothyroid, euthyroid or hyperthyroid, hypothyroid men had a lower risk of prostate cancer compared to euthyroid men (OR = 0.48, 95% CI = 0.28-0.81, p = 0.006). We observed no association between hyperthyroid status and risk, although the number of hyperthyroid men with prostate cancer was small (n = 9).

CONCLUSIONS

In this prospective study of smokers, men with elevated TSH and those classified as being in a hypothyroid state were at decreased risk of prostate cancer. Future studies should examine the association in other populations, particularly non-smokers and other racial/ethnic groups.

Prevalence and factors associated with uncomplicated storage and voiding lower urinary tract symptoms in community-dwelling Australian men

PURPOSE

To determine the prevalence of, and associated risk factors for, voiding and storage lower urinary tract symptoms (LUTS) in a population-based sample of Australian men.

METHODS

Data were collected from 1,103 men randomly selected, community-dwelling men, as part of the Florey Adelaide Male Ageing Study, after exclusion of men with prostate or bladder cancer or prior surgery to either organ. The presence of LUTS was assessed using the International Prostate Symptom Score. Urine flow was measured via flow meter. Demographic, clinical, and bio-psychosocial data were collected by questionnaire.

RESULTS

The prevalence of total, storage, and voiding LUTS was 18.1, 28.0 and 12.6%, respectively. The most common storage symptoms were frequency (12.3%), nocturia (9.9%) and urgency (8.1%), and voiding symptoms were weak stream (8.5%), intermittency (5.4%), incomplete emptying (5.1%) and straining (2.4%). There were linear associations between storage LUTS and increased abdominal fat mass, plasma glucose and low HDL cholesterol (components of the metabolic syndrome), obstructive sleep apnoea (OSA) risk, and retirement. Voiding symptoms were associated with a previous diagnosis of benign prostatic enlargement (BPH), mean peak urine flow, total energy intake, elevated risk of OSA, erectile dysfunction, physician-diagnosed thyroid dysfunction and higher household income.

CONCLUSIONS

The close association of storage LUTS with the metabolic syndrome, and of both storage and voiding LUTS with OSA, suggest that these conditions should be considered in men presenting with LUTS.