Imsr jax

All experiments were conducted in accordance with the University of Louisville Institutional Animal Care and Use Committee (protocol# 19513, approved on August 12, 2021) adhering to the National Institutes of Health Guide for the Care and Use of Laboratory Animals (8^th ed, National Research Council, 2011). Adult 6–8-week-old, 18–25 g transgenic male or female hemizygous Thy1^YFP+ (IMSR_Jax: 003782) purchased from The Jackson Laboratory (Bar Harbor, ME, USA) were bred in-house as described here (Okada et al., 2014; Stirling et al., 2014a; Orem et al., 2020b; Rajaee et al., 2020). Adult 6–8-week-old, 18–25 g transgenic male or female advillin-Cre⁺:Ai9^fl/fl:Ai95^fl/fl mice (ISMR_JAX: 032027, IMSR_Jax:007909, IMSR_Jax: 024105, respectively; The Jackson Laboratory) were bred in house as briefly described here (Orem et al., 2020a, b). The latter express tdTomato and the genetic Ca²⁺ indicator, GCaMP6f in sensory neurons and their axons specifically due to Cre-mediated recombination by the advillin-Cre driver mice. Genotyping confirmed the presence of the transgenes.

Animal experiments using MCF7 cell-line and PDX models were performed at the Mayo Clinic under Institutional Animal Care and Use Committee approval (Protocol ID: A00005364–20). Six- to 8-week-old female NOD.Cg-Prkdc^scid Il2rg^tm1Wjl/SzJ mice were used in all animal models (IMSR_JAX:005557, The Jackson Laboratory). These xenograft models were supplemented with exogenous estradiol in drinking water (8 mg/mL, 2/wk refreshed). Ten-million cells were suspended in 100 μL Matrigel and injected into the mammary fat pad to generate cell-line xenografts. The ER⁺ breast cancer PDX models were established by implanting tumor fragments subcutaneously in the flank of female mice. The cell-line or PDXs with volumes between 100 and 200 mm³ were enrolled in treatment groups. Enzalutamide or RAD140 was administered as a single agent or in combination with fulvestrant. ENZ (25 mg kg⁻¹ d⁻¹) and RAD140 (50 mg kg⁻¹ d⁻¹) were resuspended in 0.5% carboxymethyl cellulose and delivered 5 times per week by oral gavage. Fulvestrant was given as subcutaneous injection (2 mg/wk in sesame oil). Tumor volume and body weight were measured twice a week. Tumor volume was calculated using the formula (length × width²) / 2. Upon reaching experimental endpoints, mice were sacrificed and the primary tumors were kept at −80°C for further analysis.