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Dome, B.

Publications and source records attributed to Dome, B..

3 recordsLinked to original sources

Combination of enhanced gene activation and cell death causes lethal inflammatory pulmonary fibrosis

The current paradigm of inflammatory disease etiology is that it is caused by an aberrant increase in either gene activation or cell death. Studying the linear ubiquitin (linUb) chain assembly complex (LUBAC) was instrumental in proving that immune-receptor-dependent cell death can cause inflammatory disease. As LUBAC regulates both, gene activation and cell death, it can, however, also serve to evaluate the inflammatory-disease-initiating role of gene activation. Investigating mice with two different gene-activation-enhancing point mutations in LUBAC components showed that aberrantly increased gene activation in Hoil 1C458A/C458A mice did not cause pathology. In contrast, in HoipN101A/N101A mice it led to untoward cell death which, unexpectedly, was required for pathological inflammation, culminating in lethal lung fibrosis resembling human idiopathic pulmonary fibrosis (IPF). Hence, we here uncover a new etiology of inflammation, whereby aberrantly enhanced gene activation can be root cause of pathological, fibrogenic inflammation, yet intriguingly via inducing untoward cell death.

cell biology↗

Small Particles, Big Problems: Polystyrene nanoparticles induce DNA damage, oxidative stress, migration, and mitogenic pathways predominantly in non-malignant lung cells

Polystyrene micro-and nanoplastics (PS-MNPs) are emerging environmental pollutants with potential implications for human health. In this study, we used two different sizes of PS-MNPs (0.25 {micro}m and 1 {micro}m) on non-small cell lung cancer (A549, H460), small cell lung cancer (DMS53, H372), and normal lung epithelial (BEAS-2B) cells, as well as on human-derived lung organoids, to investigate the cytotoxic effects of PS particles. At lower concentrations (< 30 {micro}g/cm2, equivalent to 50 {micro}g/ml), neither PS-MPs nor PS-NPs did not interfere with cell viability or proliferation. Intracellular kinetic assays revealed that non-malignant (BEAS-2B) lung cells showed the strongest turnover of PS-NPs compared to malignant cells. Since PS-NPs exhibited more pronounced cellular effects, we focused further analyses on their impact. Furthermore, we observed significantly increased migration, prolonged S-phase arrest along with induced DNA damage, and oxidative stress in non-malignant (BEAS-2B) lung cells. Thus, our data suggest that BEAS-2B cells exhibit the highest sensitivity to PS-NPs. We also demonstrate that after PS-NP treatment, these cells displayed decreased base excision repair capacity and increased activation of survival pathways, including AKT and ERK phosphorylation. PS-NP internalization and increase of signal pathways were validated in a more physiological lung organoid setting. Altogether, our findings suggest that PS-NPs do not significantly affect the malignant behavior of cancer cells. However, they could promote tumor-like features in normal lung cells by inducing survival pathways, migration, and alterations in stress response mechanisms. Environmental ImplicationsThis study investigates the effects of polystyrene micro-and nanoplastics (PS-MNPs) at environmentally relevant concentrations. The tested concentrations of PS-MNPs (0, 15, 30, and 60 {micro}g/cm2, equivalent to 0, 25, 50, and 100 {micro}g/ml) are commonly studied in the literature in lung cells. While these findings provide insights into cellular responses, the overall environmental impact of PS-MNPs remains limited at realistic exposure levels. HighlightsO_LIPS-MNPs are internalized into lung cells, with higher uptake in non-malignant cells. C_LIO_LIPS-NPs lead to increased migration, DNA damage, oxidative stress, and disturbed cell cycle progression. C_LIO_LIPS-NPs promote activation of survival pathways in non-malignant cells and lung organoids. C_LIO_LIExposure of PS-NPs may cause potential implications for lung cancer development and progression. C_LI

molecular biology↗

Small Cell Lung Cancer Neuroendocrine Subtypes are Associated with Different Immune Microenvironment and Checkpoint Molecule Distribution

Small cell lung cancer (SCLC) has recently been sub-categorized into neuroendocrine (NE)- high and NE-low subtypes showing immune desert and immune oasis phenotypes, respectively. We aimed to characterize the immune cell localization and the microenvironment according to immune checkpoints and NE subtypes in human SCLC tissue samples at the protein level. In this cross-sectional study, we included 32 primary tumors and matched lymph node (LN) metastases of resected early-stage, histologically confirmed SCLC patients, which were previously clustered into NE subtypes using NE-associated key RNA genes. Immunohistochemistry (IHC) was performed on FFPE TMAs with antibodies against CD45, CD3, CD8 and immune checkpoints including poliovirus receptor (PVR) and Indoleamine 2,3-dioxygenase (IDO). According to our results, the stroma was significantly more infiltrated by immune cells both in primary tumors and LN metastases (vs tumor cell nests). Immune (CD45+) cell density was significantly higher in tumor nests (110.6 {+/-} 24.95 vs 42.74 {+/-} 10.30, cell/mm2, p= 0.0048), with increased CD8+ effector T cell infiltration (21.81 {+/-} 5.458 vs 3.16 {+/-} 1.36 cell/mm2, p < 0.001) in NE-low vs NE-high tumors. Furthermore, the expression of IDO was confirmed on stromal and endothelial cells, and it positively correlated (r= 0.755, p<0.01) with higher immune cell density both in primary tumors and LN metastases, regardless of the NE pattern. Expression of IDO in tumor nests was significantly higher in NE-low (vs NE-high) primary tumors. PVR expression was significantly higher in NE-low (vs NE-high) patients both in primary tumors) and LN metastases. To our knowledge, this is the first human study that demonstrates in situ that NE-low tumors are associated with increased immune cell infiltration compared to NE-high tumors. PVR and IDO are potential new targets in SCLC, with increased expression in the NE-low subtype, providing key insight for further prospective studies on potential biomarkers and targets for SCLC immunotherapies.

cancer biology↗