Biology subjects

Nastiuk, K. L.

Publications and source records attributed to Nastiuk, K. L..

7 recordsLinked to original sources

bioRxiv2025

Cell-resolved high-dimensional imaging analysis, therapeutic modeling, and a Phase Ib clinical study validate BCL-2 as a target across heterogeneous CRPC subtypes

BCL-2 has been implicated in prostate cancer (PCa) progression and development of castration-resistant disease (CRPC). However, it remains unclear how the BCL-2- and AR-expressing PCa cell populations evolve across the PCa continuum, how AR molecularly regulates BCL-2 and whether BCL-2 represents a common therapeutic target in heterogeneous CRPC. Importantly, BCL-2 inhibitors have yet to be approved for treating PCa patients. Here we first show the selective induction of BCL-2 by AR pathway inhibitors (ARPIs) in both patient specimens and xenograft models. Vectra-based quantitative multiplex immunofluorescence (qmIF) and image mass cytometry (IMC) analyses with single-cell resolution reveal markedly expanded BCL-2+ (AR+ or AR-) PCa cell populations in CRPC. Mechanistically, AR represses BCL-2 transcription through genomic binding via several AR binding sites and ARPIs relieve this repression, leading to BCL-2 upregulation. Comprehensive therapeutic studies in cells, organoids and xenografts establish that castration-induced BCL-2 is not merely associated with resistance but represents a shared and actionable vulnerability as the BCL-2 inhibitor ABT-199 potently suppressed the growth of multiple subtypes of CRPC. A Phase Ib clinical trial (NCT03751436) combining enzalutamide and BCL-2 inhibitor venetoclax demonstrated reduced circulating tumor cells in responding patients. Together, our findings elucidate the AR+/-BCL-2+/- PCa cell subpopulation dynamics during PCa progression, reveal a direct mechanistic link between AR inhibition and BCL-2-mediated resistance, and provide a strong rationale for targeting BCL-2 from the outset to eliminate emerging resistant subpopulations, inhibit treatment-induced cellular heterogeneity and plasticity, and improve therapeutic outcomes in CRPC.

cancer biology↗

bioRxiv2025

Increasing Stemness Drives Prostate Cancer Progression, Plasticity, Therapy Resistance and Poor Patient Survival

BackgroundCancer progression is often accompanied by dedifferentiation and acquisition of stem cell-like properties (stemness). In prostate cancer (PCa), lineage plasticity and therapy resistance remain major clinical challenges, yet a unified quantitative transcriptomic framework connecting stemness, androgen receptor (AR) signaling, castration resistance, and disease progression across the PCa continuum is lacking. MethodsWe integrated 87,339 transcriptomic profiles from 33 preclinical and clinical datasets spanning the PCa continuum from normal prostate and treatment-naive primary PCa (Pri-PCa) to PCa treated with neoadjuvant ADT (nADT) and metastatic castration-resistant PCa (mCRPC), with single-cell RNA-seq analyses encompassing 115,197 cells. Cancer stemness was quantified using a transcriptome-derived mRNA-based Stemness Index (mRNAsi; hereafter Stemness), and a 12-gene PCa-Stem signature was developed to capture PCa-specific stemness. Stemness, PCa-Stem, canonical AR activity (c_AR-A), castration-reprogrammed AR activity (cr_AR-A), RB1-loss, PTEN-loss, and MYC activity signatures were quantified across cohorts. Functional validation included MYC inhibition and representative PCa-Stem signature gene depletion in PCa models. Clinical prognostic significance was evaluated in independent patient cohorts. ResultsThe Stemness score and c_AR-A increased concordantly during early prostate tumorigenesis but diverged with PCa progression: as Gleason grade increased, c_AR-A declined while Stemness continually increased. mCRPC exhibited the highest Stemness and lowest c_AR-A, a pattern recapitulated in Pten/Rb1/Trp53-deficient mouse models. Global Stemness increased progressively across the PCa continuum, was enriched in aggressive PAM50-LumB and PCS1 subtypes, associated with proliferative and lineage plasticity programs, and predicted poor patient survival. The newly derived 12-gene PCa-Stem signature provided a PCa-specific molecular representation of Stemness and tracked disease progression and poor patient survival. Network analyses identified a coordinated mitotic regulatory program linking MYC activity, RB1-loss, cr_AR-A, and the PCa-Stem signature. Spatial and single-cell transcriptomic analyses localized the PCa-Stem program to lineage plasticity-related epithelial cells and demonstrated progressive expansion of PCa-Stem epithelial cells during PCa progression. Functional perturbation of representative PCa-Stem signature genes, as well as genetic and pharmacological MYC inhibition, consistently suppressed Stemness-associated phenotypes in diverse PCa models. ConclusionsCancer Stemness quantitatively captures PCa aggressiveness, lineage plasticity, treatment resistance, disease progression, and poor patient survival. cr_AR-A, RB1 loss, and MYC activation cooperate to reinforce the high-Stemness state and therapy resistance in mCRPC. Collectively, our work establishes a trajectory-integrated transcriptomic framework defining cancer Stemness as a quantifiable molecular and clinical determinant of PCa aggressiveness, lineage plasticity, disease progression, therapy resistance and patient survival.

cancer biology↗

bioRxiv2023

Androgen deprivation triggers a cytokine signaling switch to induce immune suppression and prostate cancer recurrence

Androgen deprivation therapy (ADT) is an effective but not curative treatment for advanced and recurrent prostate cancer (PC). We investigated the mechanisms controlling the response to androgen-deprivation by surgical castration in genetically-engineered mouse models (GEMMs) of PC, using high frequency ultrasound imaging to rigorously measure tumor volume. Castration initially causes almost all tumors to shrink in volume, but many tumors subsequently recur within 5-10 weeks. Blockade of tumor necrosis factor (TNF) signaling a few days in advance of castration surgery, using a TNFR2 ligand trap, prevents regression in a PTEN-deficient GEMM. Following tumor regression, a stem cell-like population within the tumor increases along with TNF protein levels. Tumor cell lines in culture recapitulate these in vivo observations, suggesting the possibility that stem cells are the source of TNF. When TNF signaling blockade is administered immediately prior to castration, tumors regress but recurrence is prevented. This implies that a late wave of TNF secretion within the tumor - which coincides with the expression of NF{kappa}B regulated genes - drives recurrence. The inhibition of signaling downstream of an NF{kappa}B-regulated protein - chemokine C-C motif ligand 2 (CCL2) - prevents post-castration tumor recurrence, phenocopying post-castration (late) TNF signaling blockade. CCL2 was originally identified as a macrophage chemoattractant and indeed at late times after castration gene sets related to chemotaxis and migration are up-regulated. Importantly, enhanced CCL2 signaling during the tumor recurrence phase coincides with an increase in pro-tumorigenic macrophages and a decrease in CD8 T cells, suggesting that recurrence is driven at least in part by tumor immunosuppression. In summary, we demonstrate that a therapy-induced switch in TNF signaling induces an immunosuppressive tumor microenvironment and concomitant tumor recurrence.

cancer biology↗

bioRxiv2022

Stromal resistance to castration-induced prostate regression in a mouse model of benign prostatic hyperplasia

Benign prostatic hyperplasia (BPH) is a non-neoplastic proliferative disease producing lower urinary tract symptoms related to the enlarged prostate. BPH is pathologically characterized by hyperplastic growth in both epithelial and stromal compartments. Androgen signaling is essential for prostate function and androgen blockade is the second-line medical therapy to relieve symptoms of BPH. Here we examined the prostates of probasin promoter-driven prolactin (Pb-PRL) transgenic mice, a robust model of BPH that spontaneously develops prostate enlargement, to investigate prostate regression in response to surgical castration. Serial ultrasound imaging demonstrated very uniform self-limited growth of Pb-PRL prostate volume that is consistent with the benign, limited cellular proliferation characteristic of BPH and that contrasts with the highly variable, exponential growth of murine prostate cancer models. Castration elicited only a partial reduction in prostate volume, relative to castration-induced regression of the normal prostate gland. The anti-androgen finasteride induced a diminished reduction of Pb-PRL prostate volume versus castration alone. The limited extent of Pb-PRL mouse prostate volume regression correlated with the initial volume of the stromal compartment, suggesting a differential sensitivity to androgen withdrawal of the epithelial and stroma compartments. Indeed, two-dimensional morphometric analyses revealed a distinctly reduced rate of regression for the stromal compartment in Pb-PRL mice. The myofibroblast component of the Pb-PRL prostate stroma appeared normal, but contained more fibroblasts and extracellular collagen deposition. Like normal prostate, the rate of regression of the Pb-PRL prostate was partially dependent on TGF{beta} and TNF signaling, but unlike the normal prostate, the extent of castration-induced regression was not affected by TGF{beta} or TNF blockade. Our studies show that androgen deprivation can effectively reduce the overall volume of hyperplastic prostate, but the stromal compartment is relatively resistant, suggesting additional therapies might be required to offer an effective treatment for the clinical manifestations of BPH.

pathology↗

bioRxiv2022

TNF signaling is required for castration-induced vascular damage preceding prostate cancer regression

The mainstay treatment for locally advanced, recurrent, or metastatic prostate cancer (PrCa) is androgen deprivation therapy (ADT). ADT causes prostate cancers to shrink in volume, or regress, by inducing epithelial tumor cell apoptosis. In normal, non-neoplastic murine prostate, androgen deprivation via castration induces prostate gland regression that is dependent on TNF signaling. Besides this direct mechanism of action, castration has also been implicated in an indirect mechanism of prostate epithelial cell death which has been described as vascular regression. The initiating event is endothelial cell apoptosis and/or increased vascular permeability. This subsequently leads to reduced blood flow and perfusion, and then hypoxia, which may enhance epithelial cell apoptosis. Castration-induced vascular regression has been observed in both normal and neoplastic prostate. We used photoacoustic, power Doppler, and contrast-enhanced ultrasound imaging, and CD31 immunohistochemical staining of the microvasculature to assess vascular integrity in the period immediately following castration, enabling us to test the role of TNF signaling in vascular regression. In two mouse models of androgen-responsive prostate cancer, TNF signaling blockade using a soluble TNFR2 ligand trap reversed the functional aspects of vascular regression as well as structural changes in the microvasculature, including reduced vessel wall thickness, cross-sectional area and vessel perimeter length. These results demonstrate that TNF signaling is required for vascular regression, most likely inducing endothelial cell apoptosis and increasing vessel permeability. Since TNF is also the critical death receptor ligand for prostate epithelial cells, we propose that TNF is a multi-purpose, comprehensive signal within the prostate cancer micro-environment mediating prostate cancer regression following androgen deprivation. SIGNIFICANCEThese studies define TNF as the mediator of androgen deprivation therapy-induced functional and structural vascular damage in prostate tumors.

cancer biology↗

bioRxiv2021

Glucocorticoid signaling delays castration-induced regression in murine models of prostate cancer

Androgen deprivation therapy (ADT) induces regression of recurrent and advanced prostate cancer (PrCa), but many tumors recur. To understand the response to ADT, changes in tumor volume were imaged after castration of murine PrCa models. While mouse (non-tumor) prostate begins to regress within two days of castration, murine PrCa regresses after a delay of 3-14 days in two distinct mouse models. Intra-tumoral androgens are undetectable after castration, but tumor cells proliferate during this period. Intratumoral glucocorticoids and glucocorticoid receptor (GR) protein increase, as does GR mRNA and a set of GR-regulated genes specifically in tumor epithelial cells identified using scRNAseq. A selective GR antagonist (CORT125281, relacorilant), in clinical trials for late-state PrCa, eliminates the delayed regression phenotype in both models. Thus, activated GR signaling and murine tumor proliferation following castration resembles the GR-dependent escape mechanism of castrate resistant PrCa. These results suggest simultaneous inhibition of GR and androgen receptor signaling could improve PrCa therapy. In briefAndrogen deprivation therapy for high risk and recurrent prostate cancers is initially effective, but ultimately fails; better understanding the mechanisms should improve therapy. In two murine prostate cancer models, GR signaling is activated immediately following castration, substituting for the acute reduction in AR signaling, and allowing for continued tumor growth. This continued growth is blocked by relacorilant, selective GR antagonist in clinical trials for late-state PrCa. HighlightsO_LIAndrogen deprivation therapy induces regression of prostate cancer, but tumors recur C_LIO_LIMurine PrCa continues to proliferate for 3-14 days in two distinct mouse prostate cancer models C_LIO_LITumor cells proliferate during this period, and intratumoral glucocorticoids and glucocorticoid receptor (GR) protein increase, as does GR mRNA and a set of GR-regulated genes C_LIO_LIRelacorilant, a selective GR antagonist in clinical trials for late-state PrCa, eliminates the delayed regression C_LI

cancer biology↗

bioRxiv2021

TNF Blockade Reduces Prostatic Hyperplasia and Inflammation while Limiting BPH Diagnosis in Patients with Autoimmune Disease

Benign prostatic hyperplasia (BPH) is ostensibly linked to autoimmune (AI) diseases, but whether the prostate is a target of systemic inflammation associated with AI conditions is unknown. Prostatic inflammation is linked to fibrosis, hyperplasia, and reduced responses to BPH-related medical therapies. This study was conducted to determine if AI disease correlates with BPH diagnosis and whether systemic targeting of an inflammatory mediator limits prostatic inflammation and hyperplasia. Patient medical records (n=112,152) were evaluated to determine BPH prevalence among different AI diseases. Inflammatory cells from human BPH tissues were analyzed by single-cell (sc)RNA-seq and the tumor necrosis factor (TNF)-antagonist etanercept was tested in two murine models of prostatic enlargement. BPH prevalence was significantly higher among patients with AI disease compared to unaffected individuals. However, AI patients treated with TNF-antagonists had a significantly reduced incidence of BPH. Data from scRNA- seq identified macrophages as a dominant source of TNF and in vitro assays confirmed that TNF stimulates BPH-derived fibroblast proliferation. In the AI patient cohort and murine models, systemic treatment with TNF-antagonists decreased prostatic epithelial proliferation, macrophage infiltration, and epithelial NF{kappa}B activation compared to control tissues. These studies are the first to show that patients with AI diseases have a heightened susceptibility to BPH and that the TNF-signaling axis is important for BPH pathogenesis. Macrophage-secreted TNF may mechanistically drive BPH via chronic activation of the signaling axis and NF{kappa}B. TNF blockade appears to be a promising new pharmacological approach to target inflammation and suppress BPH. One sentence summaryPatient data and mouse models suggest that repurposing tumor necrosis factor alpha blockade reduces inflammation-mediated prostatic hyperplasia.

cell biology↗