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Obradovic, A. Z.

Publications and source records attributed to Obradovic, A. Z..

2 recordsLinked to original sources

TMPO promotes cellular dissemination and metastasis in circulating tumor cells

Metastasis--the process by which cancer cells spread beyond the primary tumor to distant organs--accounts for the vast majority of cancer-related deaths. To elucidate mechanisms underlying dissemination and metastasis in prostate cancer, we have investigated circulating tumor cells (CTCs) obtained from genetically engineered mouse models (GEMMs). The phenotypic and molecular properties of the CTCs, and organoids derived from these CTCs, closely model the tumor and metastatic phenotypes of their parental GEMMs. Moreover, organoids derived from individual CTCs exhibit molecular and morphological heterogeneity that is associated with distinct metabolic states as well as differences in human prostate cancer outcome. Using computational systems analyses, we have identified TMPO, encoding the nuclear membrane protein lamina-associated polypeptide 2 (Lap2), as a key driver of this heterogeneity. TMPO activity is upregulated in advanced human prostate tumors, metastases, and CTCs, and is associated with adverse clinical outcome. Our findings indicate that TMPO promotes dissemination and metastasis in vivo by enhancing survival in conditions of metabolic stress, and reveal a novel mechanistic link between CTC heterogeneity, stress adaptation, and metastatic potential.

cell biology↗

Single-Cell RNAseq Analysis Reveals Robust Anti-PD-1-Mediated Increase of Immune Infiltrate in Metastatic Castration-Sensitive Prostate Cancer

Compared to other malignancies, the tumor microenvironment (TME) of primary and castration-resistant prostate cancer (CRPC) is relatively devoid of immune infiltrates. While androgen deprivation therapy (ADT) induces a complex immune infiltrate in localized prostate cancer, both in animal models and humans, the TME composition of metastatic, castration-sensitive prostate cancer (mCSPC) is relatively unknown and the effects of ADT and other treatments are poorly characterized in this context. To address this challenge, we analyzed metastatic sites from patients enrolled on a phase 2 clinical trial (NCT03951831), in which men were treated with standard-of-care chemo-hormonal therapy with anti-PD-1 immunotherapy, at the single cell level. Longitudinal protein activity-based analysis of TME subpopulations identified immune subpopulations conserved across multiple metastatic sites, their dynamic, treatment-mediated evolution, and associated clinical response features. Our study revealed a therapy-resistant, transcriptionally distinct tumor subpopulation, which comprises an increasing number of cells in treatment-refractory patients, and identified several druggable targets in both tumor and immune cells as candidates to advance treatment and improve outcomes for patients with mCSPC.

cancer biology↗