Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2022.12.03.518865

Syngeneic model of carcinogen-induced tumor mimics basal/squamous, stromal-rich, and neuroendocrine molecular and immunological features of muscle-invasive bladder cancer

Shah, S. D.·Gillard, B. M.·Wrobel, M. M.·Karasik, E.·Moser, M. T.·Mastri, M.·Sule, N.·Brackett, C. M.·HUSS, W. J.·Foster, B. A.
View original source ↗Export metadata ↓

Abstract

BackgroundBladder cancer is a heterogenous disease and the emerging knowledge on molecular classification of bladder tumors could have impact to drive treatment decisions based on molecular subtype. Pre-clinical models representing each subtype are needed to test novel therapies. Carcinogen-induced bladder cancer models represent heterogeneous, immune-competent, pre-clinical testing options with many features found in the human disease. MethodsInvasive bladder tumors were induced in C57BL/6 mice when continuously exposed to N-butyl-N-(4-hydroxbutyl nitrosamine) (BBN) in the drinking water. Tumors were excised and serially passed by subcutaneous implantation into sex-matched syngeneic C57BL/6 hosts. Eight tumor lines were developed and named BBN-induced Urothelium Roswell Park (BURP) tumor lines. The BURP lines were characterized by applying consensus molecular classification to RNA expression, histopathology, and immune profiles by CIBERSORT. Two lines were further characterized for cisplatin response. ResultsEight BURP tumor lines were established with 3 male and 3 female BURP tumor lines, having the basal/squamous (BaSq) molecular phenotype and morphology. BURP-16SR was established from a male mouse and has a stromal-rich (SR) molecular phenotype and a sarcomatoid carcinoma morphology. BURP-19NE was established from a male mouse and has a neuroendocrine (NE)-like molecular phenotype and poorly differentiated morphology. The established BURP tumor lines have unique immune profiles with fewer immune infiltrates compared to their originating BBN-induced tumors. The immune profiles of the BURP tumor lines capture some of the features observed in the molecular classifications of human bladder cancer. BURP-16SR growth was inhibited by cisplatin treatment, while BURP-24BaSq did not respond to cisplatin. ConclusionsThe BURP tumor lines represent several molecular classifications, including basal/squamous, stroma-rich, and NE-like. The stroma-rich (BURP-16SR) and NE-like (BURP-19NE) represent unique immunocompetent models that can be used to test novel treatments in these less common bladder cancer subtypes. Six basal/squamous tumor lines were established from both male and female mice. Overall, the BURP tumor lines have less heterogeneity than the carcinogen-induced tumors and can be used to evaluate treatment response without the confounding mixed response often observed in heterogeneous tumors. Additionally, basal/squamous tumor lines were established and maintained in both male and female mice, thereby allowing these tumor lines to be used to compare differential treatment responses between sexes.

Source connections

Explore related subjects

cancer biologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Shah, S. D., Gillard, B. M., Wrobel, M. M., Karasik, E., Moser, M. T., Mastri, M., Sule, N., Brackett, C. M., HUSS, W. J., Foster, B. A.. 2022-12-05. Syngeneic model of carcinogen-induced tumor mimics basal/squamous, stromal-rich, and neuroendocrine molecular and immunological features of muscle-invasive bladder cancer. https://doi.org/10.1101/2022.12.03.518865

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

The Phospholipase A2 Activity of Peroxiredoxin 6 Protects Hepatocarcinoma Cells Against Ferroptosis and Mitophagy Impairment

Peroxiredoxin 6 (PRDX6) is a moonlighting protein that plays a key role in regulating redox homeostasis and lipid metabolism through its unique dual peroxidase and calcium-independent phospholipase A2 (iPLA2) activities. Here, we generated a stable HepG2 cell line harboring a D140A mutation to selectively ablate iPLA2 activity, and we compared its phenotype with that of wild-type (WT) and PRDX6-knockout (KO) cells. D140A exhibited low ROS leves, similar to WT cells, confirming that oxidative stress is due to peroxidase deficiency. In contrast, D140A cells displayed higher lipid peroxidation than WT cells, though significantly lower than that of KO cells. Furthermore, the D140A mutant mirrored the KO phenotype regarding intracellular ferrous iron accumulation, impaired lipid droplet biogenesis, and the downregulation of the key ferroptosis regulator GPX4. Mechanistically, integrated proteomic, lipidomic, and enzymatic analyses revealed that a deficiency in iPLA2 activity of PRDX6 disrupted the release of key lipid species necessary for cell structure and signaling. Consequently, organelles involved in lipid synthesis and trafficking, such as peroxisomes, endoplasmic reticulum, mitochondria and lipid droplet, were affected. Specifically, we found that mitochondria exhibited a reduction in cristae and a diminished capacity for mitophagy and autophagy, which ultimately makes cells much more susceptible to erastin-induced ferroptotic cell death. Taken together, our findings demonstrate that PRDX6 iPLA2 activity uniquely coordinates organelle lipid homeostasis and mitophagy to protect cancer cells from ferroptotic cell death. Consequently, the use of iPLA2 inhibitors such as MJ33, which decreased PRDX6 iPLA2 activity to a level comparable to the mutant D140A, could represent a promising therapeutic strategy for inducing ferroptotic cell death in hepatocellular carcinoma.

cancer biology↗
bioRxiv2026

Serum extracellular vesicle proteomics reveals treatment-associated biomarkers in pancreatic ductal adenocarcinoma

Background Longitudinal biomarkers of treatment response in pancreatic ductal adenocarcinoma (PDAC) are needed. Extracellular vesicle (EV)-enriched serum proteomics may provide a minimally invasive approach for monitoring systemic and tumor-associated responses to therapy. Methods Paired pre-treatment and post-treatment serum samples were analyzed from 51 patients with pancreatic cancer, including 25 treated with FOLFIRINOX and 20 treated with gemcitabine-based therapy. EVs were enriched using the Mag-Net method and profiled by data independent acquisition mass spectrometry. After batch correction and filtering, 941 proteins were retained for differential and pathway analyses. Paired linear models and gene set enrichment analyses were used to assess treatment-associated changes. Baseline protein abundance and longitudinal changes were evaluated in relation to overall survival (OS) using Cox models. Results A total of 2,089 EV-associated proteins were identified, with an average of 1,186 proteins quantified per sample. Across the cohort, 26 proteins differed between post- and pretreatment samples. Proteins that increased after treatment were primarily related to extracellular matrix organization and cell adhesion, whereas proteins that decreased after treatment were associated with actin cytoskeletal organization, coagulation, and hemostasis. Treatment-associated changes were more pronounced in the FOLFIRINOX group, in which 32 proteins were differentially expressed. FOLFIRINOX was characterized by coordinated reductions in platelet- and coagulation-associated proteins, including PF4, PF4V1, PPBP, GP5, ITGA2B, and ITGB3, accompanied by enrichment of platelet activation, coagulation, and hemostasis pathways among down-regulated processes. No individual proteins met the same significance threshold in the gemcitabine group. A composite seven-protein platelet score decreased significantly after FOLFIRINOX but not for gemcitabine, and the between-regimen difference in score change was significant. Higher pretreatment ITGB1 abundance was associated with longer OS after multiple-testing correction (HR, 0.112; BH-FDR = 0.0063). In multivariable analysis, greater treatment-associated platelet-score depletion was independently associated with shorter OS (HR per unit increase in {Delta}score, 0.56; P = 0.030). Conclusions Longitudinal serum EV-enriched proteomics identified treatment-associated biological changes in PDAC, including a coordinated platelet-related response predominantly observed after FOLFIRINOX. Baseline ITGB1 abundance and longitudinal platelet-score changes represent potentially complementary prognostic and pharmacodynamic markers. These findings are exploratory and require validation in larger, independent cohorts incorporating platelet counts, coagulation measurements, and targeted proteomic assays.

cancer biology↗
bioRxiv2026

BAF complexes cooperate with lineage-restricted transcription factors to establish cell-state-specific regulatory programs

BRG1/BRM-associated factor (BAF) complexes are essential regulators of chromatin organization and cell identity. Genes encoding BAF subunits are among the most frequently mutated in human cancer. Yet, how disruption of a single subunit gives rise to distinct tumor states remains poorly understood. Atypical teratoid rhabdoid tumors (ATRTs) provide a compelling model, as they are uniformly driven by bi-allelic loss of the BAF subunit SMARCB1, yet segregate into distinct molecular subtypes. Using integrated multi-omics profiling of patient-derived ATRT organoids and primary tumor tissues, we show that transcriptional and chromatin accessibility changes upon SMARCB1 reconstitution are directed by subtype- and lineage-specific transcription factor (TF) repertoires. Genome-wide binding and transcriptomic analyses reveal that SMARCB1 reconstitution enables the lineage-specific TF RFX4 to engage regulatory elements and activate neuronal differentiation programs, partially reprogramming ATRT-MYC toward an ATRT-SHH-like identity. Together, these findings demonstrate that SMARCB1 loss disrupts TF-dependent chromatin priming, revealing that the lineage-specific regulatory output of BAF complexes is constrained by the underlying TF repertoire.

cancer biology↗