Estrogens drive myeloid-derived suppressor cell accumulation

Stress keratin 17 and estrogen support viral persistence and modulate the immune environment during cervicovaginal murine papillomavirus infection

A murine papillomavirus, MmuPV1, infects both cutaneous and mucosal epithelia of laboratory mice and can be used to model high-risk human papillomavirus (HPV) infection and HPV-associated disease. We have shown that estrogen exacerbates papillomavirus-induced cervical disease in HPV-transgenic mice. We have also previously identified stress keratin 17 (K17) as a host factor that supports MmuPV1-induced cutaneous disease. Here, we sought to test the role of estrogen and K17 in MmuPV1 infection and associated disease in the female reproductive tract. We experimentally infected wild-type and K17 knockout (K17KO) mice with MmuPV1 in the female reproductive tract in the presence or absence of exogenous estrogen for 6 mon. We observed that a significantly higher percentage of K17KO mice cleared the virus as opposed to wild-type mice. In estrogen-treated wild-type mice, the MmuPV1 viral copy number was significantly higher compared to untreated mice by as early as 2 wk postinfection, suggesting that estrogen may help facilitate MmuPV1 infection and/or establishment. Consistent with this, viral clearance was not observed in either wild-type or K17KO mice when treated with estrogen. Furthermore, neoplastic disease progression and cervical carcinogenesis were supported by the presence of K17 and exacerbated by estrogen treatment. Subsequent analyses indicated that estrogen treatment induces a systemic immunosuppressive state in MmuPV1-infected animals and that both estrogen and K17 modulate the local intratumoral immune microenvironment within MmuPV1-induced neoplastic lesions. Collectively, these findings suggest that estrogen and K17 act at multiple stages of papillomavirus-induced disease at least in part via immunomodulatory mechanisms.

Inhibition of Tumor Microenvironment Cytokine Signaling Sensitizes Ovarian Cancer Cells to Antiestrogen Therapy

Simple Summary

Antiestrogen hormonal therapy is a relatively low side effect, orally administered cancer treatment option, yet response rates have been limited in epithelial ovarian cancer despite estrogen receptor expression in many tumors. This suggests that other pathways impact estrogen response. Cytokine signaling from the tumor microenvironment promotes ovarian cancer growth, and crosstalk between cytokine signaling and estrogen signaling has been reported in other tumor types. We therefore aimed to investigate whether cytokine signaling impacts estrogen signaling in high-grade serous ovarian cancer. We demonstrated crosstalk between these two pathways in patient-derived samples, in vitro and in animal studies. We found that inhibiting interleukin-6/leukemia inhibitory factor (IL6/LIF) cytokine signaling activates estrogen signaling and blocking both pathways was synergistic in inhibiting tumor cell growth. These results suggest a potential role for combination therapy for epithelial ovarian cancer patients.

Abstract

Antiestrogen therapy (AET) is an alternative to cytotoxic chemotherapy for recurrent ovarian cancer, yet the often short duration of response suggests mechanisms of resistance. We previously demonstrated that tumor microenvironment interleukin-6/leukemia inhibitory factor (IL6/LIF) cytokines induce tumor cell JAK-STAT signaling to promote cancer growth. Crosstalk between estrogen signaling and cytokine signaling has been reported. Therefore, we sought to characterize the impact of IL6/LIF signaling on estrogen signaling in epithelial ovarian cancer and investigate the efficacy of combination therapy. We first assessed patient tumors for cytokine expression and compared it with response to AET to determine clinical relevance. In vitro, we determined the effect of IL6/LIF on estrogen receptor expression and signaling. Cell viability assays were used to determine the efficacy and potential synergy of cytokine blockade and AET. We then extended studies to animal models, incorporating patient-derived stromal cells. Our results demonstrated shorter progression-free interval on AET in patients with stromal IL6/LIF expression. In vitro, IL6/LIF increased tumor cell estrogen receptor expression and signaling, and combination cytokine blockade and AET resulted in synergistic inhibition of tumor cell growth. The anticancer effect was verified in a mouse model. In conclusion, due to crosstalk between IL6/LIF cytokine signaling and estrogen signaling, dual blockade is a potential new treatment approach for ovarian cancer.

Altered crosstalk of estradiol and progesterone with Myeloid-derived suppressor cells and Th1/Th2 cytokines in early miscarriage is associated with early breakdown of maternal-fetal tolerance

PROBLEM

Decline in myeloid-derived suppressor cells (MDSCs) and Th2 cytokines levels lead to early miscarriage (EM) but how the hormonal milieu of the body regulates MDSCs and Th1/Th2 cytokine balance is still a matter of investigation.

METHOD OF STUDY

Peripheral blood and decidua samples were collected from 20 EM patients, and 20 healthy pregnant women opted for elective abortion. MDSCs and G-MDSCs levels were analyzed in peripheral blood mononuclear cells, and Th1/Th2 cytokines levels were determined in serum via flow cytometry. Estrogen (E2), Progesterone (P4), and Testosterone levels were measured via ELISA. Further, proliferation and apoptosis in decidual samples were checked via immunoblot/immunohistochemistry of estrogen receptor -α (ER-α), STAT-3/pSTAT-3, and caspase-3, respectively.

RESULTS

Our results clearly indicate that in EM patients; decline in E2 and P4 significantly correlates with decline in MDSCs, particularly with subtype granulocytic MDSCs (G-MDSCs) and skewness of the Th1/Th2 cytokines balance toward Th1 response. Downregulation of ER- α and increased caspase-3 expression in endometrium decidua signifies poor endometrial receptivity in EM. STAT-3 activation regulates proliferation, differentiation and suppressive potency of MDSCs. In decidua of EM, significantly lower expression of pSTAT-3 indicates that these processes pertaining to MDSCs are compromised.

CONCLUSION

Altogether, this unfavorable systemic milieu may drive toward early breakdown of maternal-fetal tolerance in EM. Therefore, regulated crosstalk of E2, P4 with MDSCs and balanced Th1/Th2 cytokines is prerequisite for successful pregnancy.