Biology subjects

Bolis, M.

Publications and source records attributed to Bolis, M..

11 recordsLinked to original sources

bioRxiv2026

Age-driven miR-29 trades youthful plasticity for epigenetic fidelity

Throughout life, somatic cells must preserve their identity while retaining the capacity to adapt. How this balance shifts with ageing and rejuvenation remains unclear. Here we identify miR-29 as a central point of convergence between the transcriptional programmes of physiological ageing and two routes to rejuvenation: induced reprogramming and the natural reset of early development. miR-29 rises with ageing, falls in both rejuvenation settings and shows the most conserved age-associated increase across vertebrates. miR-29 inhibition opposes transcriptional ageing, whereas mimics promote an older transcriptional state. Methylome analysis reveals a broader function: inhibition releases the miR-29 brake on remodelling, and mimic treatment reinforces it. This release increases methylation at repeat-associated CpGs and lowers epigenetic-clock estimates through unequal contributions in opposite directions. Inhibition also amplifies stimulus-induced methylation changes but reduces fidelity to lineage-specific methylation patterns. We extend this relationship to cancer, where low miR-29 expression marks tumours with younger epigenetic-age estimates yet greater methylation divergence from their tissue of origin. These findings identify miR-29 as a control point linking ageing, rejuvenation and cancer, and support a maladaptive trade-off model in which epigenetic fidelity is preserved at the expense of the plasticity needed for methylome maintenance and adaptation.

cell biology↗

bioRxiv2026

An integrated, transcript-resolution atlas of prostate cancer progression unmasks associations with oncogenic pathways

Most genes produce multiple non-coding and coding RNA transcripts with potentially divergent biological functions, yet their contribution to cancer remains largely unexplored. Here, we built an integrated, transcript-resolution RNA sequencing atlas of prostate cancer spanning 1,140 clinical samples from 10 independent studies, covering the full range of disease progression from normal tissue to primary, hormone-sensitive, and castration-resistant disease. Cross-study integration removes technical batch effects while retaining the biological heterogeneity that distinguishes these disease states, a property we validate against long-read sequencing and leverage to place newly incorporated external cohorts within this disease-progression context. We describe transcript patterns of oncogenic and tumor-suppressive long non-coding RNAs along disease progression and identify 41 protein-coding genes with significant isoform switches in cancer-relevant pathways, including WNT2B, RNF43, RELA, BRCA1, ROCK2, and TRIM11. Finally, we provide the Prostate Cancer Atlas (www.prostatecanceratlas.org), an interactive web resource that lets researchers contextualize their own transcriptomic data against this atlas.

cancer biology↗

bioRxiv2025

Loss of ESE3/EHF is sufficient to promote cell plasticity, transformation and androgen-independent status in the early stage of prostate carcinogenesis.

Phenotypic plasticity enables tumor progression and treatment resistance. However, its timing and underlying mechanisms are poorly understood. Here, we demonstrate that cell plasticity can emerge early during prostate cancer development, resulting from the knockout of the epithelial-specific ETS transcription factor EHF in prostate epithelial cells. Inspecting the transcriptome of human prostate cancers, we identified a correlation between low EHF expression, loss of luminal epithelial identity, and attenuated androgen signaling in both primary tumors and castration-resistant prostate cancers (CRPC). In EHF knockout mouse models and human epithelial cells, EHF ablation was sufficient to disrupt epithelial cell lineage integrity and promote a progenitor/stem cell-like state with both basal and luminal features, enabling high plasticity and multi-lineage phenotypic transitions. Mechanistically, EHF acted as a central node controlling a hierarchy of transcriptional regulatory factors and downstream signaling pathways (e.g., COL1A1/DDR1, JAK/STAT3), thereby regulating epithelial lineage integrity and restricting stemness and phenotypic transitions. Activation of these downstream pathways, consequent to EHF loss, promoted non-luminal cell features, attenuated androgenic response, and resistance to AR antagonists. Collectively, these data provide novel insights into the causes of phenotypic plasticity and androgen indifference already at the early stages of prostate tumorigenesis and a new perspective on the paths to cancer progression directly relevant to the development of more efficient treatment strategies.

cancer biology↗

bioRxiv2025

Targeting FOXA1 and FOXA2 Disrupts the Lineage-Specific Oncogenic Output Program in Prostate Cancer

Activation of the androgen receptor (AR) is the key lineage-specific oncogenic pathway and the primary therapeutic target in prostate cancer. While AR signaling is enabled by the pioneer transcription factor FOXA1, its homolog FOXA2 is specifically expressed in advanced lineage plasticity prostate cancers that have lost the AR signaling axis. However, their roles and utility as drug targets remain incompletely characterized. Here, we show an unexpected collaboration of FOXA1 and FOXA2 in mediating AR-independent cell proliferation in different lineage plasticity cancer subtypes. Conversely, joint loss-of-function or pharmacologic disruption of FOXA1 and FOXA2 leads to the collapse of lineage-specific oncogenic transcription factors followed by cell cycle arrest. In summary, our findings uncover a druggable dependency for AR-positive and - negative prostate cancers.

cancer biology↗

bioRxiv2025

TRIM24 Degradation Counteracts Adaptation to Androgen Receptor Inhibition in Prostate Cancer

The androgen receptor (AR) is the primary therapeutic target in prostate cancer. While androgen deprivation therapy (ADT) and androgen receptor signaling inhibitors (ARSi) are effective, the disease eventually progresses to fatal castration-resistant prostate cancer (CRPC). That said, little is known about the mechanisms in residual disease that initiates tumor relapse upon ADT/ARSi. Here, we discover a crucial role for TRIM24 in supporting the survival of residual cell clusters primed for tumor relapse in vivo. Consequently, reducing TRIM24 with bifunctional degraders (dTRIM24) significantly delays or even prevents the emergence of CRPC in the context of AR reactivation and lineage plasticity. dTRIM24 not only inhibits AR signaling but also counteracts adaptive pathways engaged by AR inhibition itself, such as STAT3 activation and EMT. Our findings underscore the potential of TRIM24 as an effective and druggable target for preventing prostate cancer progression under AR inhibition. SignificanceDespite advances in targeting AR signaling in prostate cancer, tumor relapse remains a major concern. Here, we provide evidence that more durable responses can be achieved by pharmacologically degrading TRIM24. At the molecular level, TRIM24 degradation inhibits both AR signaling and adaptive pathways that enable tumor relapse.

cancer biology↗

bioRxiv2024

Androgen receptor-negative prostate cancer is vulnerable to SWI/SNF-targeting degrader molecules

Proteolysis targeting chimera (PROTAC) therapies degrading SWI/SNF ATPases offer a novel approach to interfere with androgen receptor (AR) signaling in AR-dependent castration-resistant prostate cancer (CRPC-AR). To explore the utility of SWI/SNF therapy beyond AR-sensitive CRPC, we investigated SWI/SNF-targeting agents in AR-negative CRPC. SWI/SNF targeting PROTAC treatment of cell lines and organoid models reduced the viability of not only CRPC-AR but also WNT-signaling dependent AR- negative CRPC (CRPC-WNT). The CRPC-WNT subgroup represents 11% of around 400,000 cases of CRPC worldwide who die yearly of CRPC. We discovered that SWI/SNF ATPase SMARCA4 depletion interfered with the master transcriptional regulator TCF7L2 (TCF4) in CRPC-WNT. Functionally, TCF7L2 maintains proliferation via the MAPK signaling axis in this subtype of CRPC. These data suggest a mechanistic rationale for interventions that perturb the DNA binding of the pro-proliferative TCF7L2 transcription factor (TF) and/or direct MAPK signaling inhibition in the CRPC-WNT subclass of advanced prostate cancer. Statement of significanceAndrogen receptor (AR)-negative prostate cancer (PCa) remains a clinical challenge due to the lack of targeted therapeutic options. Here, we identified a lineage-defining molecular axis in a subtype of AR- negative PCa, accounting for around 10% of castration-resistant PCa (CRPC) that can be interfered with by SWI/SNF-targeting agents.

cancer biology↗

bioRxiv2023

JUN mediates senescence and immune cell recruitment to prevent prostate cancer progression

BackgroundProstate cancer develops through malignant transformation of the prostate epithelium in a stepwise, mutation-driven process. Although activator protein-1 transcription factors such as JUN have been implicated as potential oncogenic drivers, the molecular programs contributing to prostate cancer progression are not fully understood. MethodsWe analyzed JUN expression in clinical prostate cancer samples across different stages and investigated its functional role in a Pten-deficient mouse model. We performed histopathological examinations, transcriptomic analyses and explored the senescence-associated secretory phenotype in the tumor microenvironment. ResultsElevated JUN levels characterized early-stage prostate cancer and predicted improved survival in human and murine samples. Immune-phenotyping of Pten-deficient prostates revealed high accumulation of tumor-infiltrating leukocytes, particularly innate immune cells, neutrophils and macrophages as well as high levels of STAT3 activation and IL-1{beta} production. Jun depletion in a Pten-deficient background prevented immune cell attraction which was accompanied by significant reduction of active STAT3 and IL-1{beta} and accelerated prostate tumor growth. Comparative transcriptome profiling of prostate epithelial cells revealed a senescence-associated gene signature, upregulation of pro-inflammatory processes involved in immune cell attraction and of chemokines such as IL-1{beta}, CCL3 and CCL8 in Pten-deficient prostates. Strikingly, JUN depletion reversed both, senescence and senescence-associated immune cell infiltration and consequently accelerated tumor growth. ConclusionsOur results suggest that JUN acts as tumor-suppressor and decelerates the progression of prostate cancer by transcriptional regulation of senescence- and inflammation-associated genes. This study opens avenues for novel treatment strategies that could impede disease progression and improve patient outcomes.

cancer biology↗

bioRxiv2023

Cancer-specific association between Tau (MAPT) and cellular pathways, clinical outcome, and drug response

Tau (MAPT) is a microtubule-associated protein causing common neurodegenerative diseases or inherited frontotemporal lobar degenerations. Emerging evidence for non-canonical functions of Tau in DNA repair and P53 regulation suggests its involvement in cancer. Indeed, preliminary studies have correlated Tau expression with cancer survival or response to therapies. To bring new evidence for a relevant role of Tau in cancer, we carried out an in silico pan-cancer analysis of MAPT transcriptomic profile in over 10000 clinical samples from 32 cancer types and over 1300 pre-clinical samples from 28 cancer types provided by the TCGA and the DEPMAP datasets respectively. MAPT expression associated with key cancer hallmarks including inflammation, proliferation, and epithelial to mesenchymal transition, showing cancer-specific patterns. In some cancer types, MAPT functional networks were affected by P53 mutational status. We identified new associations of MAPT with clinical outcomes and drug response in a context-specific manner. Overall, our findings indicate that the MAPT gene is a potential major player in multiple types of cancer. Importantly, the impact of Tau on cancer seems to be heavily influenced by the specific cellular environment.

cancer biology↗

bioRxiv2023

Tau protein modulates an epigenetic mechanism of cellular senescence

Progressive Tau deposition in neurofibrillary tangles and neuropil threads is the hallmark of tauopathies, a disorder group that includes Alzheimers disease. Since Tau is a microtubule-associated protein, a prevalent concept to explain the pathogenesis of tauopathies is that abnormal Tau modification contributes to dissociation from microtubules, assembly into multimeric {beta}-sheets, proteotoxicity, neuronal dysfunction and cell loss. Tau also localizes in the cell nucleus and evidence supports an emerging function of Tau in DNA stability and epigenetic modulation. To better characterize the possible role of Tau in regulation of chromatin compaction and subsequent gene expression, we performed a bioinformatics analysis of transcriptome data obtained from Tau-depleted human neuroblastoma cells. Among the transcripts deregulated in a Tau-dependent manner, we found an enrichment of target genes for the polycomb repressive complex 2. We further describe decreased cellular amounts of the core components of the polycomb repressive complex 2 complex and a lower histone 3 trimethylation activity in Tau deficient cells. Among the de-repressed polycomb repressive complex 2 target gene products, IGFBP3 protein was found to be linked to increased senescence induction in Tau-deficient cells. Our findings propose a mechanism for Tau-dependent epigenetic modulation of cell senescence, a key event in pathologic aging.

cell biology↗

bioRxiv2021

Minor intron splicing efficiency increases with the development of lethal prostate cancer

Here we explored the role of minor spliceosome (MiS) function and minor intron-containing gene (MIG) expression in prostate cancer (PCa). We show MIGs are enriched as direct interactors of cancer-causing genes and their expression discriminates PCa progression. Increased expression of MiS U6atac snRNA, including others, and 6x more efficient minor intron splicing was observed in castration-resistant PCa (CRPC) versus primary PCa. Notably, androgen receptor signalling influenced MiS activity. Inhibition of MiS through siU6atac in PCa caused minor intron mis-splicing and aberrant expression of MIG transcripts and encoded proteins, which enriched for MAPK activity, DNA repair and cell cycle. Single cell-RNAseq confirmed cell cycle defects and lineage dependency on the MiS from primary to CRPC and neuroendocrine PCa. siU6atac was [~]50% more efficient in lowering tumor burden of CRPC cells and organoids versus current state-of-the-art combination therapy. In all, MiS is a strong therapeutic target for lethal PCa and potentially other cancers. Graphical AbstractU6atac expression, MiS activity, and minor intron splicing correlate with PCa therapy resistance and PCa progression to CRPC-adeno and transdifferentiation to CRPC-NE. One major MiS regulator during that process is the AR-axis, which is re-activated during CRPC-adeno and blocked in CRPC-NE. Molecularly, an increase in MiS dependent splicing promotes changes of transcriptome and proteome. This results in cell cycle activation, increased MAPK signalling and increased DNA repair. U6atac mediated MiS inhibition renders MiS splicing error-prone through increased intron retention and alternative splicing events, which results in cell cycle block and decreased MAPK signalling and DNA repair. MiS inhibition blocks all stages of PCa. Figure created with BioRender.com. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=154 SRC="FIGDIR/small/471104v1_ufig1.gif" ALT="Figure 1"> View larger version (61K): org.highwire.dtl.DTLVardef@1c1c296org.highwire.dtl.DTLVardef@1ce1416org.highwire.dtl.DTLVardef@88d842org.highwire.dtl.DTLVardef@2ddf96_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

bioRxiv2020

Patient-derived xenografts and organoids model therapy response in prostate cancer

Therapy resistance and metastatic processes in prostate cancer (PCa) remain undefined, due to lack of experimental models that mimic different disease stages. We describe a novel androgen-dependent PCa patient-derived xenograft (PDX) model from treatment-naive, soft tissue metastasis (PNPCa). RNA and whole-exome sequencing of the PDX tissue and organoids confirmed transcriptomic and genomic similarity to primary tumor. PNPCa harbours BRCA2 and CHD1 somatic mutations, shows an SPOP/FOXA1-like transcriptomic signature and microsatellite instability, which occurs in 3% of advanced PCa and has never been modelled in vivo. Comparison of the treatment-naive PNPCa with additional metastatic PDXs (BM18, LAPC9), in a medium-throughput organoid screen of FDA-approved compounds, revealed differential drug sensitivities. Multikinase inhibitors (ponatinib, sunitinib, sorafenib) were broadly effective on all PDX- and patient-derived organoids from advanced cases with acquired resistance to standard-of-care compounds. This proof-of-principle study may provide a preclinical tool to screen drug responses to standard-of-care and newly identified, repurposed compounds.

cancer biology↗