8 research outputs found
Study of neuroprotective activity of new acetylcholinesterase inhibitors TVA and TVS in experimental model of Alzheimer’s disease
Alzheimer’s disease (AD) is a severe neurodegenerative disease characterized by loss of synaptic connection between neurons of the cortex and subcortical regions. Therefore, the study of new AChEIs with less toxic impact and better effectivity is a topical challenge. In view of this, we synthesized novel chemical compounds: TVA and TVS that possess AChEI activity and studied their neuroprotective effect in an experimental AD mode
3D collagen migration patterns reveal a SMAD3-dependent and TGF-β1-independent mechanism of recruitment for tumour-associated fibroblasts in lung adenocarcinoma
The TGF-β1 transcription factor SMAD3 is epigenetically repressed in tumour-associated fibroblasts (TAFs) from lung squamous cell carcinoma (SCC) but not adenocarcinoma (ADC) patients, which elicits a compensatory increase in SMAD2 that renders SCC-TAFs less fibrotic. Here we examined the effects of altered SMAD2/3 in fibroblast migration and its impact on the desmoplastic stroma formation in lung cancer.We used a microfluidic device to examine descriptors of early protrusions and subsequent migration in 3D collagen gels upon knocking down SMAD2 or SMAD3 by shRNA in control fibroblasts and TAFs.High SMAD3 conditions as in shSMAD2 fibroblasts and ADC-TAFs exhibited a migratory advantage in terms of protrusions (fewer and longer) and migration (faster and more directional) selectively without TGF-β1 along with Erk1/2 hyperactivation. This enhanced migration was abrogated by TGF-β1 as well as low glucose medium and the MEK inhibitor Trametinib. In contrast, high SMAD2 fibroblasts were poorly responsive to TGF-β1, high glucose and Trametinib, exhibiting impaired migration in all conditions.The basal migration advantage of high SMAD3 fibroblasts provides a straightforward mechanism underlying the larger accumulation of TAFs previously reported in ADC compared to SCC. Moreover, our results encourage using MEK inhibitors in ADC-TAFs but not SCC-TAFs.© 2022. The Author(s)
Epigenetic SMAD3 Repression in Tumor-Associated Fibroblasts Impairs Fibrosis and Response to the Antifibrotic Drug Nintedanib in Lung Squamous Cell Carcinoma
The tumor-promoting fibrotic stroma rich in tumor-associated
fibroblasts (TAF) is drawing increased therapeutic attention.
Intriguingly, a trial with the antifibrotic drug nintedanib in non–
small cell lung cancer reported clinical benefits in adenocarcinoma
(ADC) but not squamous cell carcinoma (SCC), even though the
stroma is fibrotic in both histotypes. Likewise, we reported that
nintedanib inhibited the tumor-promoting fibrotic phenotype of
TAFs selectively in ADC. Here we show that tumor fibrosis is
actually higher in ADC-TAFs than SCC-TAFs in vitro and patient
samples. Mechanistically, the reduced fibrosis and nintedanib
response of SCC-TAFs was associated with increased promoter
methylation of the profibrotic TGFb transcription factor SMAD3
compared with ADC-TAFs, which elicited a compensatory increase
in TGFb1/SMAD2 activation. Consistently, forcing global DNA
demethylation of SCC-TAFs with 5-AZA rescued TGFb1/SMAD3
activation, whereas genetic downregulation of SMAD3 in ADCTAFs and control fibroblasts increased TGFb1/SMAD2 activation,
and reduced their fibrotic phenotype and antitumor responses to
nintedanib in vitro and in vivo. Our results also support that
smoking and/or the anatomic location of SCC in the proximal
airways, which are more exposed to cigarette smoke particles, may
prime SCC-TAFs to stronger SMAD3 epigenetic repression,
because cigarette smoke condensate selectively increased SMAD3
promoter methylation. Our results unveil that the histotype-specific
regulation of tumor fibrosis in lung cancer is mediated through
differential SMAD3 promoter methylation in TAFs and provide
new mechanistic insights on the selective poor response of SCCTAFs to nintedanib. Moreover, our findings support that patients
with ADC may be more responsive to antifibrotic drugs targeting
their stromal TGFb1/SMAD3 activation.
Significance: This study implicates the selective epigenetic
repression of SMAD3 in SCC-TAFs in the clinical failure
of nintedanib in SCC and supports that patients with ADC
may benefit from antifibrotic drugs targeting stromal TGFb1/
SMAD3
Epigenetic SMAD3 Repression in Tumor-Associated Fibroblasts Impairs Fibrosis and Response to the Antifibrotic Drug Nintedanib in Lung Squamous Cell Carcinoma
The tumor-promoting fibrotic stroma rich in tumor-associated
fibroblasts (TAF) is drawing increased therapeutic attention.
Intriguingly, a trial with the antifibrotic drug nintedanib in non–
small cell lung cancer reported clinical benefits in adenocarcinoma
(ADC) but not squamous cell carcinoma (SCC), even though the
stroma is fibrotic in both histotypes. Likewise, we reported that
nintedanib inhibited the tumor-promoting fibrotic phenotype of
TAFs selectively in ADC. Here we show that tumor fibrosis is
actually higher in ADC-TAFs than SCC-TAFs in vitro and patient
samples. Mechanistically, the reduced fibrosis and nintedanib
response of SCC-TAFs was associated with increased promoter
methylation of the profibrotic TGFb transcription factor SMAD3
compared with ADC-TAFs, which elicited a compensatory increase
in TGFb1/SMAD2 activation. Consistently, forcing global DNA
demethylation of SCC-TAFs with 5-AZA rescued TGFb1/SMAD3
activation, whereas genetic downregulation of SMAD3 in ADCTAFs and control fibroblasts increased TGFb1/SMAD2 activation,
and reduced their fibrotic phenotype and antitumor responses to
nintedanib in vitro and in vivo. Our results also support that
smoking and/or the anatomic location of SCC in the proximal
airways, which are more exposed to cigarette smoke particles, may
prime SCC-TAFs to stronger SMAD3 epigenetic repression,
because cigarette smoke condensate selectively increased SMAD3
promoter methylation. Our results unveil that the histotype-specific
regulation of tumor fibrosis in lung cancer is mediated through
differential SMAD3 promoter methylation in TAFs and provide
new mechanistic insights on the selective poor response of SCCTAFs to nintedanib. Moreover, our findings support that patients
with ADC may be more responsive to antifibrotic drugs targeting
their stromal TGFb1/SMAD3 activation.
Significance: This study implicates the selective epigenetic
repression of SMAD3 in SCC-TAFs in the clinical failure
of nintedanib in SCC and supports that patients with ADC
may benefit from antifibrotic drugs targeting stromal TGFb1/
SMAD3
Bacteria-produced ferric exopolysaccharide nanoparticles as iron delivery system for truffles (Tuber borchii)
Iron exopolysaccharide nanoparticles were biogenerated duringferric citrate fermentation by Klebsiella oxytoca DSM 29614. Before investigating their effects on Tuber borchii (Bianchetto^ truffle) mycelium growth and morphology, they were tested on human K562 cell line and Lentinula edodes pure culture and shown to be non-toxic. Using these nanoparticles as iron supplement, the truffles showed extremely efficient iron uptake of over 300 times that of a commercial product. This avoided morphological changes in T. borchii due to lack of iron during growth and, with optimum nanoparticle dosage, increased growth without cell wall disruption or alteration of protoplasmatic hyphal content, the nuclei, mitochondria, and rough endoplasmic reticula being preserved. No significant modifications in gene expression were observed. These advantages derive from the completely different mechanism of iron delivery to mycelia compared to commercial iron supplements. The present data, in fact, show the nanoparticles attached to the cell wall, then penetrating it non-destructively without damage to cell membrane, mitochondria, chromatin, or ribosome. Low dosage significantly improved mycelium growth, without affecting hyphal mor- phology. Increases in hyphal diameter and septal distance indicated a healthier state of the mycelia compared to those grown in the absence of iron or with a commercial iron supplement. These positive effects were confirmed by measuring fungal biomass as mycelium dry weight, total protein, and ergosterol content. This Bgreen^ method for biogenerating iron exopolysaccharide nanoparticles offers many advantages, including significant economic savings, without toxic effects on the ectomycorrhizal fungus, opening the possibility of using them as iron supplements in truffle plantations