Biology subjects

Castagna, N.

Publications and source records attributed to Castagna, N..

5 recordsLinked to original sources

bioRxiv2025

A transition zone enriched WIF1⁺ basal cell subtype is associated with benign prostatic hyperplasia

ABSTRACT/SUMMARYThe cellular composition and disease susceptibilities of the distinct zones of the human prostate remain incompletely understood. Through extensive single-cell RNA sequencing (scRNA-seq) of benign regions from prostatectomy specimens, we identified a basal cell population expressing WIF1, VCAN, and NRG1, among other genes, that was significantly enriched in the transition zone (TZ). Benign prostatic hyperplasia (BPH) is a common condition that causes widespread morbidity and is nearly exclusively localized to the TZ. Analysis of previously published scRNA-seq datasets further confirmed that WIF1+ basal cells were significantly enriched in BPH compared to normal prostate. Pathway and cell-cell communication analyses revealed that this basal subtype is associated with programs related to cell proliferation, epithelial-mesenchymal transition (EMT), angiogenesis, and hormone response. Together, the molecular signature, zonal distribution, and pathway enrichment suggest that TZ-enriched WIF1+ basal cells may contribute to BPH pathogenesis by promoting epithelial and stromal remodeling.

cell biology↗

bioRxiv2024

Triptolide sensitizes cancer cells to nucleoside DNA methyltransferase inhibitors through inhibition of DCTPP1-mediated cell-intrinsic resistance

While nucleoside DNA methyltransferase inhibitors (DNMTi) such as decitabine and azacitidine are effective in treating myelodysplatic syndrome (MDS)/leukemia, they have had limited utility for the majority of other cancers. Through a chemical library screen, we identified that triptolide, a diterpenoid epoxide from Tripterygium wilfordii, or analogs significantly augmented the epigenetic and anti-cancer effects of decitabine in vitro and in vivo. These effects were attributable to inhibition of DCTPP1-mediated cleavage of 5-aza-deoxycytidine triphosphate, the convergent activated metabolite of nucleoside DNMTi, leading to enhanced drug incorporation into genomic DNA, increased DNMT degradation, enhanced global DNA demethylation and associated transcriptional reprogramming. We show that high DCTPP1 expression was associated with cell-intrinsic resistance to nucleoside DNMTi, and that triptolide and its analogs could overcome this resistance. SIGNIFICANCEWe screened a library of existing drugs to identify those capable of enhancing the anti-cancer effects of the nucleoside DNMTi decitabine. The combination of triptolide and decitabine synergistically inhibited cancer cell growth and survival in vitro, and was highly effective in inhibiting xenograft growth in vivo. Biochemical, genetic and structural biology studies with triptolide and its analogs revealed that this synergy was due to their inhibition of DCTPP1-mediated pyrophosphate cleavage from 5-aza-deoxycytidine triphosphate, the active metabolite of DNMTi. The genomic incorporation and efficacy of decitabine in cancer cell lines were significantly correlated with DCTPP1 expression more so than those of other nucleoside metabolizing genes. Triptolide and its analogs comprise rational adjuncts to nucleoside DNMTi ripe for further pre-clinical/clinical translation. HIGHLIGHTSO_LITriptolide synergistically sensitizes cancer cells to DNMTi in vitro. C_LIO_LITriptolide and decitabine combination shows favorable efficacy and safety in vivo. C_LIO_LISynergy of triptolide and decitabine is mediated through inhibition of DCTPP1. C_LIO_LIHigh DCTPP1 expression confers cell intrinsic resistance to DNMTi. C_LI

cancer biology↗

bioRxiv2023

Convergent alterations in the tumor microenvironment of MYC-driven human and murine prostate cancer

The tissue microenvironment in prostate cancer is profoundly altered. While such alterations have been implicated in driving prostate cancer initiation and progression to aggressive disease, how prostate cancer cells and their precursors mediate those changes is unclear, in part due to the inability to longitudinally study the disease evolution in human tissues. To overcome this limitation, we performed extensive single-cell RNA-sequencing (scRNA-seq) and rigorous molecular pathology of the comparative biology between human prostate cancer and key time points in the disease evolution of a genetically engineered mouse model (GEMM) of prostate cancer. Our studies of human tissues, with validation in a large external data set, revealed that cancer cell-intrinsic activation of MYC signaling was the top up-regulated pathway in human cancers, representing a common denominator across the well-known molecular and pathological heterogeneity of human prostate cancer. Likewise, numerous non-malignant cell states in the tumor microenvironment (TME), including non-cancerous epithelial, immune, and fibroblast cell compartments, were conserved across individuals, raising the possibility that these cell types may be a sequelae of the convergent MYC activation in the cancer cells. To test this hypothesis, we employed a GEMM of prostate epithelial cell-specific MYC activation in two mouse strains. Cell communication network and pathway analyses suggested that MYC oncogene-expressing neoplastic cells, directly and indirectly, reprogrammed the TME during carcinogenesis, leading to the emergence of cascading cell state alterations in neighboring epithelial, immune, and fibroblast cell types that paralleled key findings in human prostate cancer. Importantly, among these changes, the progression from a precursor-enriched to invasive-cancer-enriched state was accompanied by a cell-intrinsic switch from pro-immunogenic to immunosuppressive transcriptional programs with coinciding enrichment of immunosuppressive myeloid and Treg cells in the immune microenvironment. These findings implicate activation of MYC signaling in reshaping convergent aspects of the TME of prostate cancer as a common denominator across the otherwise well-documented molecular heterogeneity of human prostate cancer.

cancer biology↗

bioRxiv2022

Single-cell atlas of epithelial and stromal cell heterogeneity by lobe and strain in the mouse prostate

Evaluating the complex interplay of cell types in the tissue microenvironment is critical to understanding the origin and progression of diseases in the prostate and potential opportunities for intervention. Mouse models are an essential tool to investigate the molecular and cell-type-specific contributions of prostate disease at an organismal level. While there are well-documented differences in the extent, timing, and nature of disease development in various genetically engineered mouse models in different mouse strains and prostate lobes within each mouse strain, yet, the underlying molecular phenotypic differences in cell types across mouse strains and prostate lobes are incompletely understood. To address this, we examined the single-cell transcriptomes of individual mouse prostate lobes from two commonly used mouse strains, FVB/NJ and C57BL/6J. Data dimensionality reduction and clustering analysis revealed that basal and luminal cells possessed strain-specific transcriptomic differences, with luminal cells also displaying marked lobe-specific differences. Additionally, three rare populations of epithelial cells clustered independently of strain and lobe: one population of luminal cells expressing Foxi1 and components of the vacuolar ATPase proton pump (Atp6v0d2 and Atp6v1g3), another population expressing Psca and other stem cell-associated genes (Ly6a/Sca-1, Tacstd2/Trop-2), and a neuroendocrine population expressing Chga, Chgb, and Syp. In contrast, stromal cell clusters, including fibroblasts, smooth muscle cells, endothelial cells, pericytes, and immune cell types, were conserved across strain and lobe, clustering largely by cell type and not by strain or lobe. One notable exception to this was the identification of two distinct fibroblast populations that we term subglandular fibroblasts and interstitial fibroblasts based on their strikingly distinct spatial distribution in the mouse prostate. Altogether, these data provide a practical reference of the transcriptional profiles of mouse prostate from two commonly used mouse strains and across all four prostate lobes.

cell biology↗

bioRxiv2021

PHENOTYPIC CHARACTERIZATION OF TWO NOVEL CELL LINE MODELS OF CASTRATION RESISTANT PROSTATE CANCER.

BACKGROUNDResistance to androgen deprivation therapies is a major driver of mortality in advanced prostate cancer. Therefore, there is a need to develop new pre-clinical models that allow the investigation of resistance mechanisms and the assessment of drugs for the treatment of castration resistant prostate cancer. METHODSWe generated two novel cell line models (LAPC4-CR and VCaP-CR) which were derived by passaging LAPC4 and VCaP cells in vivo and in vitro under castrate conditions. We performed detailed transcriptomic (RNA-seq) and proteomic analyses (SWATH-MS) to delineate expression differences between castration-sensitive and castration-resistant cell lines. Furthermore, we characterized the in vivo and in vitro growth characteristics of the novel cell line models. RESULTSThe two cell line derivatives LAPC4-CR and VCaP-CR showed castration resistant growth in vitro and in vivo which was only minimally inhibited by AR antagonists, enzalutamide and bicalutamide. High-dose androgen treatment resulted in significant growth arrest of VCaP-CR but not in LAPC4-CR cells. Both cell lines maintained AR expression, but exhibited distinct expression changes on the mRNA and protein level. Integrated analyses including data from LNCaP and the previously described castration resistant LNCaP-abl cells revealed an expression signature of castration resistance. CONCLUSIONSThe two novel cell line models LAPC4-CR and VCaP-CR and their comprehensive characterization on the RNA and protein level represent important resources to study the molecular mechanisms of castration resistance.

cancer biology↗