Distinct CD8⁺ T Cell Programming in the Tumor Microenvironment Contributes to Sex Bias in Bladder Cancer Outcome

Abstract

Disclosure of Potential Conflicts of Interest: No potential conflicts of interest were disclosed. 24Abstract: Men and women show striking yet unexplained discrepancies in 25 incidence, clinical presentation, and therapeutic response across different types of 26 infectious/autoimmune diseases and malignancies 1,2 . For instance, bladder cancer 27 shows a 4-fold male-biased incidence that persists after adjustment for known risk 28 factors 3,4 . Here, we utilize murine bladder cancer models to establish that male-biased 29 tumor burden is driven by sex differences in endogenous T cell immunity. Notably, sex 30 differences exist in early fate decisions by intratumoral CD8 + T cells following their 31 activation. While female CD8 + T cells retain their effector function, male counterparts 32 readily adopt a Tcf1 low Tim3progenitor state that becomes exhausted over tumor 33 progression. Human cancers show an analogous male-biased frequency of exhausted 34 CD8 + T cells. Mechanistically, we describe an opposing interplay between CD8 + T cell 35 intrinsic androgen and type I interferon 5,6 signaling in Tcf1/Tcf7 regulation and formation 36 of the progenitor exhausted T cell subset. Consistent with female-biased interferon 37 response 7 , testosterone-dependent stimulation of Tcf1/Tcf7 and resistance to interferon 38 occurs to a greater magnitude in male CD8 + T cells. Male-biased predisposition for CD8 + 39T cell exhaustion suggests that spontaneous rejection of early immunogenic bladder 40 tumors is less common in males and carries implications for therapeutic efficacy of 41 immune checkpoint inhibitors 8,9 . 42Main: Sex is a biological variable with significant influence on immune function 1 . 43However, mechanisms underlying sex-biased incidence and mortality of various cancers 44 arising in non-reproductive organs remain elusive 2 . Indeed, bladder cancer shows a 4-45 fold male-biased incidence globally, which cannot be explained by established risk 46 factors: smoking, exposure to occupational hazards and urinary tract infection 3,4 . Here, 48 largely mediated by sex differences in T cell immunity. Flow cytometric and single cell 49 RNA-seq analyses of CD8 + tumor-infiltrating leukocytes (TILs) identified a striking male 50 bias in the formation of Tcf1 low Tim3progenitor cells 10 and in their transition to a 51 hypofunctional Tcf1 -Tim3 + exhausted state upon prolonged stimulation. In particular, 52androgen signaling was enriched in the progenitor exhausted subset. We found that 53 testosterone-induced Tcf1, an early molecular orchestrator of an exhaustion-associated 54 transcriptional landscape 11 in male CD8 + T cells, is also more resistant to pertinent 55 repression by female-biased type I interferon signaling 5 . Collectively, these findings 56 highlight sex differences in intratumoral CD8 + T cell fate as a potential mechanism 57 underlying bladder cancer sex bias and identify androgen as a possible target to modulate 58 CD8 + TIL exhaustion. 59CD8 + T cell immunity is required for sex differences in murine...

Switching Cancers: A Systematic Review Assessing the Role of Androgen Suppressive Therapy in Bladder Cancer

“…This has been confirmed with urothelial-specific AR depletion studies, which suggest AR signalling may contribute to DNA damage via the p53 pathway 22 . More recently, single-cell sequencing studies using the MB49 bladder cancer murine model suggest that a testosterone mediated exhaustion of T-cells in the bladder tumor microenvironment via a non-AR dependant mechanism may help explain the higher male incidence of bladder cancer 23 .…”

Androgen conspires with the CD8 + T cell exhaustion program and contributes to sex bias in cancer

“…We are grateful to C. Bolyard and E. Oltz for critical reading and editing of the manuscript. The discovery that androgen preferentially drives PE CD8 + T cells and a T cell exhaustion program in cancer was initially reported by us in a preprint in bioRxiv (82). Funding: This work was supported by NIH grants R01 CA213290, R01 CA262069, R01 CA255334, R01 CA262338, and R01 AI077283 (to Z.L.)…”