Androgens and breast cancer risk

Association between testosterone and cancers risk in women: a two-sample Mendelian randomization study

OBJECTIVE

Previous observational studies have explored the correlation between testosterone and cancer risk. However, the causal association between testosterone and various cancer types in women remains inconclusive. The objective of this Mendelian randomization study is to evaluate the causal links between total testosterone (TT) and bioavailable testosterone (BT) with cancer risk in females.

METHODS

Initially, a rigorous quality control process was employed to identify suitable instrumental single nucleotide polymorphisms (SNPs) associated with the exposure under investigation that exhibited a significant association. The genetic causal relationship between female testosterone levels and the risk of developing cancers was examined through a two-sample Mendelian randomization. Various analytical methods, including inverse-variance weighted (IVW), MR-Egger, weighted median, simple mode, and weighted mode, were applied in the investigation. Key findings were primarily based on the results obtained via IVW (random effects), and sensitivity analyses were conducted to assess the reliability of the obtained results. Furthermore, maximum likelihood, penalized weighted median, and IVW (fixed effects) methods were utilized to further validate the robustness of the results.

RESULTS

Based on the results of IVW analysis, our study indicated a positive causal relationship between BT and breast cancer (OR = 1.1407, 95%CI: 1.0627-1.2244, P = 0.0015) and endometrial cancer (OR = 1.4610, 95%CI: 1.2695-1.6813, P = 1.22E-06). Moreover, our findings also showed a positive causal association between TT and breast cancer (OR = 1.1764, 95%CI: 1.0846-1.2761, P = 0.0005), cervical cancer(OR = 1.0020, 95%CI: 1.0007-1.0032, P = 0.0077), and endometrial cancer(OR = 1.4124, 95%CI: 1.2083-1.6511, P = 0.0001). Additionally, our results demonstrated a negative causal relationship between BT and ovarian cancer (OR = 0.8649, 95%CI: 0.7750-0.9653, P = 0.0320). However, no causal relationship was found between BT, TT and other types of cancer (corrected P > 0.05).

CONCLUSIONS

This study elucidates the role of testosterone on the development of breast cancer, endometrial cancer, ovarian cancer, and cervical cancer. It also hints at a potential but fragile link between testosterone and bladder cancer, as well as thyroid cancer. Nonetheless, it's worth noting that no statistically significant relationship between testosterone and various other types of cancer in females was identified.

Male DCIS diagnosed after use of over-the-counter hormonal supplement

INTRODUCTION

Male breast cancer is a rare disease. Although epidemiologic and genetic factors are associated with male breast cancer, hormonal factors may also play a role.

CASE PRESENTATION

We report the case of a 39-year-old BRCA negative male patient taking a sexual performance enhancement supplement who presented with worsening asymmetric gynecomastia and unilateral spontaneous bloody nipple discharge and was found to have ductal carcinoma in-situ.

DISCUSSION

The altered cellular environment related to the hormone contents of the supplement coincided with the rapid worsening of his gynecomastia and may have played a role in the development of the ductal carcinoma in-situ, or growth of an existing focus.

CONCLUSION

The use of hormonal male enhancement supplements can lead to higher levels of androgens in users. It is possible for this altered hormonal environment to cause the growth of tumor or promote the progression of an existing focus.

Transdermal Testosterone in Female Hypoactive Sexual Desire Disorder: A Rapid Qualitative Systematic Review Using Grading of Recommendations Assessment, Development and Evaluation

Female hypoactive sexual desire disorder (HSDD) is a multifactorial sexual dysfunction disorder characterized by a decrease in sexual desire and personal distress. HSDD occurs in naturally occurring postmenopausal women or secondary to oophorectomy. Multiple studies have assessed the use of transdermal testosterone (TDT) as a management option for patients with HSDD. Our aim is to assess published studies using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) framework for the quality of evidence regarding testosterone use as a short- and long-term therapy for HSDD. We implemented this qualitative systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. We set a GRADE score of 4 (high evidence) as a cutoff point for the quality measure of published studies assessing the use of TDT in HSDD. The outcomes of interest were the efficacy of TDT on the total number of satisfying sexual activity, number of orgasms, sexual desire and distress level in patients with HSDD. These outcomes were evaluated through Sexual Activity Log (SAL), Profile of Female Sexual Function (PFSF), and Personal Distress Scale (PDS) evaluation tools. Five randomized controlled trials were identified to meet the inclusion criteria. The selected studies were of high evidence based on the GRADE score as two of the studies scored 4 points, the other two studies scored 5 points and one study scored 6 points. All of the high quality selected studies had similar outcomes suggesting high effectiveness for the use of 300 µg/d TDT with or without estrogen for the management of HSDD with minimal side effects. One study showed a trend for higher risk of breast cancer in long-term use (0.37%). The use of 300 µg/d of TDT in surgical and natural menopause is an effective plan to manage HSDD in the short- and long-term. Although side effects are minimal, further prospective research is needed to assess the more severe side effects such as breast cancer in the long-term use of TDT.

The impact of testosterone, tibolone and black cohosh on purified mammary and placental 17β-hydroxysteroid dehydrogenase type 1

CONTEXT

Mammary and placental 17β-hydroxysteroid dehydrogenase type 1 (17βHSD1).

OBJECTIVE

To assess the impact of testosterone, tibolone, and black cohosh on purified mammary and placental 17βHSD1.

MATERIALS AND METHODS

17βHSD1 was purified from human mammary gland and placenta by column chromatography, its activity was monitored by a radioactive activity assay, and the degree of purification was determined by gel electrophoresis. Photometric cofactor transformation analysis was performed to assess 17βHSD1 activity without or in presence of testosterone, tibolone and black cohosh.

RESULTS

17βHSD1 from both sources displayed a comparable basal activity. Testosterone and tibolone metabolites inhibited purified mammary and placental 17βHSD1 activity to a different extent, whereas black cohosh had no impact.

DISCUSSION

Studies on purified enzymes reveal the individual action of drugs on local regulatory mechanisms thus helping to develop more targeted therapeutic intervention.

CONCLUSION

Testosterone, tibolone and black cohosh display a beneficial effect on local mammary estrogen metabolism by not affecting or decreasing local estradiol exposure.

Risks of testosterone replacement therapy in men

Testosterone replacement therapy (TRT) is a widely used treatment for men with symptomatic hypogonadism. The benefits seen with TRT, such as increased libido and energy level, beneficial effects on bone density, strength and muscle as well as cardioprotective effects, have been well-documented. TRT is contraindicated in men with untreated prostate and breast cancer. Men on TRT should be monitored for side-effects such as polycythemia, peripheral edema, cardiac and hepatic dysfunction.

Benefits and risks of testosterone treatment for hypoactive sexual desire disorder in women: a critical review of studies published in the decades preceding and succeeding the advent of phosphodiesterase type 5 inhibitors

With advancing age, there is an increase in the complaints of a lack of a libido in women and erectile dysfunction in men. The efficacy of phosphodiesterase type 5 inhibitors, together with their minimal side effects and ease of administration, revolutionized the treatment of erectile dysfunction. For women, testosterone administration is the principal treatment for hypoactive sexual desire disorder. We sought to evaluate the use of androgens in the treatment of a lack of libido in women, comparing two periods, i.e., before and after the advent of the phosphodiesterase type 5 inhibitors. We also analyzed the risks and benefits of androgen administration. We searched the Latin-American and Caribbean Health Sciences Literature, Cochrane Library, Excerpta Medica, Scientific Electronic Library Online, and Medline (PubMed) databases using the search terms disfunção sexual feminina/female sexual dysfunction, desejo sexual hipoativo/female hypoactive sexual desire disorder, testosterona/testosterone, terapia androgênica em mulheres/androgen therapy in women, and sexualidade/sexuality as well as combinations thereof. We selected articles written in English, Portuguese, or Spanish. After the advent of phosphodiesterase type 5 inhibitors, there was a significant increase in the number of studies aimed at evaluating the use of testosterone in women with hypoactive sexual desire disorder. However, the risks and benefits of testosterone administration have yet to be clarified.

Thrombosis in Three Postmenopausal Women Receiving Testosterone Therapy for Low Libido

Our hypothesis was that thrombosis occurring in postmenopausal women given testosterone (T) or testosterone–estradiol (TE) to improve libido was associated with a prothrombotic interaction between T or TE with underlying inherited procoagulants. In three previously healthy, postmenopausal, Caucasian women with no antecedent thrombosis and previously undiagnosed G20210A prothrombin gene heterozygosity, hyperhomocysteinemia and 4G4G homozygosity of the PAI-1 gene, we describe central retinal vein thrombosis and osteonecrosis that developed at 16 days, 2 months and 11 months in the three cases, respectively, after T or TE therapy was started. Exogenous T or TE in postmenopausal women may be associated with thrombosis, speculatively when it is superimposed on underlying procoagulants. This small observational case series can serve as a starting point for a larger observational study with greater detail on patient history, serum T and estradiol levels, and detailed PCR and serologic assessment of thrombophilia and hypofibrinolysis.

Postmenopausal breast cancer, androgens, and aromatase inhibitors

Recent data can help to better define the long debated relationship between androgens and breast cancer (BC) after menopause. We reviewed the available literature data on: the origin of androgens after menopause, the association between circulating androgens and BC incidence and recurrence, the relationship between circulating and intratumoral hormones, the prognostic significance of the presence of androgen receptors (ARs) in the different BC subtypes, the androgen effect on BC cell lines, and the relationship between androgens and aromatase inhibitors. Epidemiological, clinical, and preclinical data on the role of androgens and of ARs on estrogen receptor (ER)-negative BC are somewhat controversial. However, most preclinical studies suggest that activated ARs, when present, have a proliferative effect, particularly in HER2 expressing cell lines, due to the cross-talk between AR and HER2 pathways. As regards ER-positive BC, epidemiological studies associate androgen levels with increased incidence and risk of recurrences, whilst clinical studies associate the AR positivity with a better prognosis. Preclinical studies suggest that the action of androgens is bidirectional: mainly proliferative, because circulating androgens are the precursors of estrogens, but also anti-proliferative, because AR activation restrains ER activity. The relative increase of androgenic action that follows the blocking of androgen aromatization into estrogens by aromatase inhibitors (AIs), could contribute to their therapeutic efficacy in AR-positive cases. Available data, although defining a complex picture, suggest that circulating androgen levels are clinically relevant, particularly when AIs are used.

Role of KLF5 in hormonal signaling and breast cancer development

Steroid hormones, including ovarian steroid hormones progesterone and estrogen and androgen, play vital roles in the development of normal mammary gland and breast cancer via their receptors. How these hormones regulate these physiological and pathological processes remains to be elucidated. Krüppel-like factor 5 (KLF5) is a transcription factor playing significant roles in breast carcinogenesis, whose expression has been shown to be regulated by hormones. In this review, the relationships among hormonal signaling, KLF5, and breast cancer are summarized and discussed.