The Androgen Paradox in Prostate Disease

Why the same hormone that enlarges the prostate may also calm its inflammation — and what that means for how we treat men

By Kelly Schwemmer, MD

Most men with an enlarging prostate are told a simple story: the prostate grows with age because of testosterone, so treatment means lowering the hormone that feeds it. That story is not wrong. However, it is incomplete — and the part it leaves out has become one of the more interesting unresolved questions in men's health.

Over the past fifteen years, a substantial amount of research has repositioned chronic inflammation from a bystander in benign prostatic hyperplasia (BPH) to something much closer to a central actor. At the same time, a separate line of research has produced a genuinely counterintuitive finding: androgens, in prostate tissue, appear to be anti-inflammatory. Low testosterone tracks with worse intraprostatic inflammation, not better.

Put those together and you arrive at a real clinical tension. If androgens drive prostate growth but suppress prostate inflammation, and if inflammation itself drives prostate growth, then what exactly are we doing when we lower a man's DHT — or when we raise his testosterone?

This article walks through what the literature supports, where it genuinely conflicts, and how these findings translate into clinical stratification. It is written for readers who want the mechanism rather than the summary — informed patients and clinicians alike.

Part I — Inflammation moves to the center of BPH

The classical model of BPH rests on two requirements: aging and the presence of androgens. Both are necessary. Neither is sufficient, and neither fully explains why some men develop obstructive disease and others do not.

The inflammatory hypothesis has accumulated considerable support. In a 2016 review in Nature Reviews Urology, De Nunzio and colleagues describe the prostate as an immune-competent organ in which several stimuli — infectious agents, urinary reflux, metabolic syndrome, aging, and autoimmune responses — can dysregulate local immunity. The resulting tissue damage and chronic tissue healing, they propose, contribute to the formation of BPH nodules. [1]

Bostanci and colleagues, reviewing the same question in Current Opinion in Urology, reach a similar conclusion with useful precision. Inflammatory infiltrates are frequently observed in prostate tissue from men with BPH, and the presence and degree of that inflammation correlates with prostate volume and weight. Their summary is that recent studies strongly suggest BPH is an immune-mediated inflammatory disease inducing epithelial and stromal proliferation. [2]

Two features of that literature deserve emphasis, because they are frequently lost in translation.

The evidence is associative. Bostanci and colleagues state plainly that there is still no evidence of a causal relation. Inflammation may contribute to BPH; it has not been demonstrated to cause it in any individual patient.

The drivers are multiple. Infection is one recognized trigger of prostatic inflammation — and the one that standard culture-based testing has historically been least able to detect — but it sits alongside autoimmune activity, metabolic dysfunction, urinary reflux, and aging. No single upstream cause has been isolated.

That second point matters for what follows. If inflammation were driven by one thing, the treatment question would be simple. It is not.

Part II — The paradox: DHT grows the gland, but calms the tissue

The androgen dependence of prostate growth is not in dispute. It is the entire rationale for 5-alpha reductase inhibition: block the conversion of testosterone to dihydrotestosterone (DHT), and prostate volume falls. Finasteride and dutasteride work through that mechanism.

Which makes the inflammatory data surprising.

Vignozzi and colleagues, publishing in the Journal of Endocrinology in 2012, examined inflammatory infiltrates in prostatectomy specimens from men with BPH and correlated them with serum testosterone. After adjustment for confounders, hypogonadism was associated with a fivefold increased risk of intraprostatic inflammation, and that inflammation was more severe than in eugonadal men with BPH. [3]

When human BPH-derived stromal cells were triggered with inflammatory stimuli secreting an abundance of inflammatory and growth factors. Pretreatment with DHT inhibited NF-kappaB activation and suppressed secretion. The authors concluded that DHT exerts a broad anti-inflammatory, immune-regulatory role on human prostatic stromal cells, inhibiting their capacity to induce and sustain an inflammatory response.

In this data, more androgen receptor activation produced less inflammation — and less androgen produced more. That is the opposite of the intuition most patients arrive with.

Tong and Zhou, reviewing androgen–inflammation interaction of BPH in Mediators of Inflammation, conclude that both androgens and inflammation greatly influence the occurrence and development of BPH and that the two factors affect each other — but they describe DHT in BPH tissue as potentially activating a chronic inflammatory response, amplifying inflammatory factor expression and upregulating the proliferative capacity of prostate tissue. [4]

We have two credible reviews of overlapping literature, one describing DHT as suppressing the prostatic inflammatory response and one describing it as capable of activating it. This is not a case of good data versus bad data; it is genuinely bidirectional and context-dependent.

Part III — What the molecular work adds

The cell and molecular literature clarify why a single hormone can produce opposite-seeming effects, even if it does not fully resolve it. The common node is NF-kappaB, the principal transcriptional mediator of inflammatory signaling, and its crosstalk with the androgen receptor (AR).

Understanding the inflammation-to-AR correlation, Wang and colleagues compared various inflammatory markers across BPH, prostatitis, and prostate cancer specimens, then exposed different prostate cells to an inflammatory environment. Lipopolysaccharide exposure increased cell viability, AR expression, AR-mediated transcription, and epithelial–mesenchymal transition. A NF-kappaB inhibitor decreased all three. Their conclusion was that NF-kappaB regulates AR expression in prostatitis and prostate cancer. [5]

Zhao and colleagues identified an AR-derived circular RNA that activates the NLRP3 inflammasome pathway, promoting inflammatory response and proliferation. Disrupting or blocking suppressed progression of prostate cancer xenografts. The AR pathway is essential for both tumorigenesis and inflammatory response. [6]

Malinen and colleagues examined the crosstalk directly at genome scale, co-stimulating prostate cancer cells with androgen and TNF-alpha. This combination produced a distinction from either stimulus alone, by substantial remodeling of both the AR and NF-kappaB. It was found androgen multiplied while TNF-alpha restrained the NF-kappaB cistrome. [7]

Izumi and colleagues argue that alteration of AR-mediated inflammatory signals from infiltrating immune cells and prostate stromal and epithelial cells may play key roles in disease progression — and noting that androgen deprivation alone may be insufficient to resolve either BPH or prostate cancer. [8]

A plausible reconciliation — and a caution

Note what differs across these studies: Vignozzi's anti-inflammatory finding came from BPH-derived stromal cells; the pro-inflammatory AR findings came largely from epithelial and malignant cell lines. Androgen signaling in the prostate is compartment-specific, and stromal and epithelial cells do not behave identically. Cell type, androgen concentration, the specific inflammatory stimulus, and the local versus systemic context all plausibly determine which direction the relationship runs. This is a reasonable hypothesis rather than a settled explanation, and it should be held as such.

Part IV — The long shadow: inflammation and prostate cancer

The stakes extend beyond symptom management. Sfanos and De Marzo situate prostate disease within the broader oncologic understanding of chronic inflammation, now regarded as an enabling characteristic of human cancer; they note that an estimated 20 percent of adult cancers overall are attributable to chronic inflammatory conditions arising from infectious agents, non-infectious inflammatory disease, or environmental factors, and they review proliferative inflammatory atrophy (PIA) as a candidate risk-factor lesion in prostate carcinogenesis. [9]

Two cautions belong with that figure. The 20 percent estimate is an all-cancers statistic with multiple attributed causes, not a prostate-specific or infection-specific number. And the prostate-specific evidence is not unidirectional: while several lines of work associate prostatic inflammation with elevated cancer risk, other analyses have found baseline inflammation associated with reduced risk. The relationship is under active investigation, and PIA remains a proposed precursor rather than an established one.

Staal and Beyaert's review of NF-kappaB signaling in prostate cancer adds a relevant epidemiologic note: they suggest the higher prevalence of prostate cancer in Western populations may relate to elevated inflammation from metabolic syndrome and associated comorbidities — a reminder that the inflammatory input is frequently metabolic rather than infectious. [10]

Part V — How this stratifies in practice

If the literature is genuinely bi-directional, the clinical question is not “should androgens be raised or lowered” but rather is “which patient is in front of you?”

The eugonadal man with obstructive symptoms and an enlarged gland

Normal serum testosterone, significant prostate volume, elevated PSA, bothersome lower urinary tract symptoms. This is established 5-alpha reductase inhibitor territory, frequently combined with an alpha-blocker. The goal is volume reduction, and the androgen-dependence of growth is the lever being pulled.

The hypogonadal man with symptomatic testosterone deficiency

Fatigue, diminished libido, erectile dysfunction, with laboratory-confirmed hypogonadism. Here the treatment decision is driven by the deficiency, not by the prostate. Historic concern that testosterone therapy worsens BPH or precipitates cancer has weakened considerably; the saturation model provides a rationale, holding that prostatic androgen receptors are largely saturated at relatively modest testosterone concentrations, so further increases in serum testosterone do not produce proportional prostatic growth. Contemporary practice permits testosterone therapy in men with BPH, with baseline and interval PSA, digital rectal examination, and symptom monitoring, and with greater caution in severe symptoms or a history of retention. Vignozzi's inflammatory findings are part of why the field has grown less fearful here.

The man who is both hypogonadal and significantly hyperplastic

This is where the paradox becomes a live clinical problem. Some clinicians stabilize obstructive symptoms first with a 5-ARI and/or alpha-blocker before initiating testosterone therapy; others treat concurrently with close monitoring. There is no consensus algorithm, and this scenario warrants individualized decision-making and documented shared decision-making with the patient.

The man with pain-predominant symptoms and a small gland

Pelvic pain, urgency, post-ejaculatory discomfort, without meaningful enlargement. Hormonal manipulation is not the operative lever. This is the prostatitis and chronic pelvic pain syndrome lane, where the relevant question is whether an infectious or inflammatory driver can be identified — including organisms that conventional culture may fail to detect.

The stratifying variables in practice

Serum total and free testosterone; prostate volume; PSA; symptom severity (IPSS); symptom character (obstructive versus pain and irritative); post-void residual and retention history; and metabolic status, given the consistent association between metabolic syndrome and prostatic inflammation. Inflammatory status is emerging as a stratifier but does not yet carry an established treatment algorithm — which is precisely why it merits careful individual assessment rather than protocolized assumption.

Part VI — What would settle this?

Intellectual honesty requires naming what is missing. The inflammatory hypothesis of BPH rests substantially on associative human data and mechanistic work in cell culture and animal models. What has not been done is a study that would close the loop: prospective, controlled trials demonstrating that identifying and resolving a specific inflammatory driver produces durable improvement in prostate volume, symptom scores, or long-term risk.

Until that exists, the appropriate posture is investigative rather than declarative. Inflammation is strongly implicated in BPH. Androgen signaling and inflammatory signaling are demonstrably intertwined through NF-kappaB, and the relationship runs in both directions depending on cellular context. Infection is one recognized and historically under-detected trigger of prostatic inflammation.

The clinically useful conclusion is not that we have found the cause. It is that “your PSA is normal, so nothing is wrong” is an inadequate answer for a symptomatic man — and that there is considerably more testing to be done than most men have been offered.

Evaluating your own situation

The through-line of this literature is that prostate physiology is individual. Two men with identical symptom scores may have entirely different testosterone status, metabolic profiles, inflammatory burdens, and prostate volumes — and those differences point toward different managements.

I offer a comprehensive hormone and peptide therapy consultation for men who want their own situation evaluated rather than assumed. The consultation is $249 and includes laboratory testing to assess your individual hormonal and metabolic picture, followed by a review of those results together and a discussion of what they do — and do not — indicate for you.

To be clear about what this is: it is an evaluation, not a predetermined treatment plan. Some men who complete it are appropriate candidates for hormone optimization. Others are better served by standard urologic management, by addressing metabolic contributors, or by referral. You will receive an honest assessment of which category you fall into, including when the answer is that no intervention is warranted.

This article is educational and does not constitute medical advice or establish a physician–patient relationship. It does not diagnose, treat, or screen for any disease, including prostate cancer. The evaluation described does not replace PSA testing, digital rectal examination, or routine prostate cancer screening, and men should continue age-appropriate screening as advised by their physician. Testosterone therapy, peptide therapy, and 5-alpha reductase inhibition each carry risks, benefits, and contraindications that require individual medical assessment; some therapies discussed in clinical practice are used off-label. Discuss your specific circumstances with a licensed physician.

References

1. De Nunzio C, Presicce F, Tubaro A. Inflammatory mediators in the development and progression of benign prostatic hyperplasia. Nat Rev Urol. 2016;13(10):613–626. doi:10.1038/nrurol.2016.168

2. Bostanci Y, Kazzazi A, Momtahen S, Laze J, Djavan B. Correlation between benign prostatic hyperplasia and inflammation. Curr Opin Urol. 2013;23(1):5–10. doi:10.1097/MOU.0b013e32835abd4a

3. Vignozzi L, Cellai I, Santi R, et al. Antiinflammatory effect of androgen receptor activation in human benign prostatic hyperplasia cells. J Endocrinol. 2012;214(1):31–43.

4. Tong Y, Zhou RY. Review of the roles and interaction of androgen and inflammation in benign prostatic hyperplasia. Mediators Inflamm. 2020;2020:7958316.

5. Wang GC, Huang TR, Wang KY, et al. Inflammation induced by lipopolysaccharide advanced androgen receptor expression and epithelial-mesenchymal transition progress in prostatitis and prostate cancer. Transl Androl Urol. 2021;10(11):4275–4287.

6. Zhao AN, Yang Z, Wang DD, et al. Disturbing NLRP3 acetylation and inflammasome assembly inhibits androgen receptor-promoted inflammatory responses and prostate cancer progression. FASEB J. 2022;36(11):e22602.

7. Malinen M, Niskanen EA, Kaikkonen MU, Palvimo JJ. Crosstalk between androgen and pro-inflammatory signaling remodels androgen receptor and NF-κB cistrome to reprogram the prostate cancer cell transcriptome. Nucleic Acids Res. 2017;45(2):619–630.

8. Izumi K, Li L, Chang C. Androgen receptor and immune inflammation in benign prostatic hyperplasia and prostate cancer. Clin Investig (Lond). 2014;4(10):935–950.

9. Sfanos KS, De Marzo AM. Prostate cancer and inflammation: the evidence. Histopathology. 2012;60(1):199–215. doi:10.1111/j.1365-2559.2011.04033.x

10. Staal J, Beyaert R. Inflammation and NF-κB signaling in prostate cancer: mechanisms and clinical implications. Cells. 2018;7(9):122.