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Berthiaume, L.

Publications and source records attributed to Berthiaume, L..

4 recordsLinked to original sources

Effects of Polyunsaturated Fatty Acids and Selenoneine on Growth and Lipidomic Profiles in Patient-Derived Prostate Cancer Organoids

Prostate cancer (PCa) is the second most frequent cancer in men and represents a major public health issue worldwide. To complement current therapeutic approaches, our work aims to understand the impact of nutritional interventions on PCa evolution. Recent studies showed that supplementation with omega-3 fatty acids reduces tumour growth in PCa mouse models. Several beneficial effects were observed, particularly on the gut microbiome, suggesting indirect effects on tumours, and whether these fatty acids have a direct molecular impact on the prostate remains elusive. Here, we hypothesized that the prostate directly takes up dietary fatty acids to reprogram metabolism, which could contribute to the beneficial effects on cancer treatment. To test this hypothesis, five series of patient-derived organoids (PDOs), with paired lines originating from normal and tumour samples, were treated with omega-3 and omega-6 fatty acids. While heterogeneity was observed in growth capacities of PDO lines, omega-3 supplementation overall decreased PDO growth, with a stronger decrease in PCa lines. This effect was stronger when co-treated with selenoneine, a nutrient enriched in some marine foods with high omega-3 content. Lipidomic experiments were then performed, revealing that PDOs can take up fatty acids, both omega-3 and omega-6. Furthermore, PDOs could metabolize omega-3 fatty acids into downstream metabolites, even if high inter-patient heterogeneity was observed. Altogether, this study, using PDOs as a working model to study the human prostate, provides a better understanding of the molecular impacts of fatty acid supplementation on prostate and PCa biology for the development of future nutritional interventions.

cancer biology↗

Late gestational exposure to flutamide alters stromal composition and immune landscape in the rat mammary gland during pre-puberty, peri-puberty, and adulthood

Perinatal development of the mammary gland is regulated by hormonal signals that influence cell proliferation, extracellular matrix remodeling, immune cell recruitment, and intracellular signaling. While the role of estrogen in mammary gland development is well established, the impact of androgens remains less understood. To address this gap, we inhibited androgen signaling in utero using the anti-androgen flutamide (FLU) and investigated the effects on mammary gland development in rats. Using an integrative strategy combining histology, transcriptomics, lipidomics, cytokine profiling, and high-resolution imaging, mammary tissue were analyzed at pre-puberty (postnatal days (PND) 21), peri-puberty (PND46), and adulthood (PND9O). FLU exposure induced subtle, yet significant, alterations in mammary morphology and molecular signatures. At PND2l, the FLU exposed group exhibited an increased number of adipocytes with reduced size. Transcriptomic analysis revealed differentially expressed genes at PND2l and enrichment in pathways related to androgen response and immune signaling, but minimal changes at later developmental stages. Lipidomic profiling showed transient disruption in long-chain fatty acid composition at early developmental stages. Cytokine profiling revealed a reduced adaptive immune response at PND46 and PND9O, and second harmonic generation imaging demonstrated changes in collagen fiber orientation and density across all developmental stages. These data indicate that prenatal androgen signaling is essential for proper stromal development and the establishment of early transcriptional networks in the mammary gland, with only minor long-term effects on glandular architecture in adult nulliparous females.

pharmacology and toxicology↗

An in utero exposure to the synthetic estrogen diethylstilbestrol affects the fat pad composition in post-natal mammary glands

In utero exposure to the synthetic estrogen diethylstilbestrol (DES) has been linked to developmental abnormalities and elevated breast cancer risk in adulthood in human and rodent models. While the impact of DES on the mammary epithelium has been thoroughly investigated, its effect on the other cell types of the mammary gland remains understudied. Here, given that the mammary gland development is strongly associated with its microenvironment, we aimed to investigate how in utero DES exposure alters the mammary glands stromal and immune function across key developmental stages. To achieve this aim, timed-pregnant rats were gavaged daily with DES or vehicle from gestation days 16-21, and female offspring mammary glands were analyzed at pre-puberty (postnatal day 21 (PDN21)), puberty (PND46), and adulthood (PND90). We assessed morphological and extracellular matrix changes, performed transcriptomic cell-type enrichment analysis, measured cytokine expression, and quantified immune cell populations. DES-exposed mammary glands exhibited pronounced stromal remodeling, including increased collagen deposition and orientation by adulthood. Gene expression profiling indicated DES-induced stage-specific immune alterations: immune cell signatures were enriched at PND21 and PND90 but diminished at PND46. Correspondingly, DES increased macrophage populations at PND21 while reducing T-lymphocyte numbers at PND46 and PND90. DES exposure also dysregulated inflammatory cytokine/chemokine expression in adult glands, suggesting a persistent inflammatory environment. In conclusion, in utero exposure to an estrogenic compound can reprogram mammary development, inducing long-term changes in the extracellular matrix and immune landscape. These disruptions to stromal-immune homeostasis may impair normal mammary morphogenesis and increase susceptibility to breast pathologies later in life.

pharmacology and toxicology↗

Establishment of human glioblastoma cell culture collection

Glioblastoma (GBM) is a highly aggressive primary brain cancer with poor prognosis (<15 months), highlighting the urgent need for more effective therapies. As current treatments are not effective, the need for a deeper understanding of the biology of GBM cells, including how they reprogram their metabolism to support their aberrant and uncontrolled growth, is critical. To this end, we established a collection of 41 human glioma cell lines derived from freshly resected tumour tissues from 99 patients. We characterized 12 of these cell lines by combining histologic, genetic, stem cell derivation and self-renewal, and metabolomic analyses. Histological and genetic profiles included IDH mutation status, Ki-67 proliferation index, ATRX status, mutant TP53 expression, chromosome 10q loss, EGFR amplification, and MGMT promoter methylation. Of these, only p53 mutation expression status showed weak segregation of the cell lines into 2 separate metabolic groups based on amino acid levels, but none showed an effect on stem cell derivation or self-renewal. Further characterization of these 12 cell lines revealed significant metabolic and phenotypic differences when comparing mesenchymal versus proneural gene expression subtyping. We show significant increases in TCA cycle metabolites in mesenchymal-like GBM cells and higher overall metabolic activity compared to proneural-like cells. These findings highlight the complexity of GBM and the need for personalized treatments that consider the metabolome of each subtype as a potential therapeutic avenue.

cancer biology↗