Biology subjects

Accardi, D.

Publications and source records attributed to Accardi, D..

3 recordsLinked to original sources

bioRxiv2024

Heterotypic competition between cancer cells and hepatocytes generates heterogeneous context-dependent phenotypes

Competitive interactions between tumor cells and surrounding healthy cells are constantly present during the progression of a solid tumor, and their outcome has been proposed to affect the clinical behavior. Previous studies have described various mechanistic and molecular aspects that characterize this process, overall indicating that cancer cells behave as supercompetitors, which eliminate neighboring healthy cells to gain vital space for growth and infiltration of the tissue. Nevertheless, there is a lack of systematic characterization of these competitive interactions, particularly in the context of cancer in mammals. Furthermore, previous studies in the field of cell competition have primarily focused on homotypic cell competition, involving different clones of the same cell or cells deriving from the same tissue. Data are scarce regarding heterotypic cell competition between two unrelated cell types, which is particularly critical for the understanding of metastatic tumors. In this research, we study cell competition in the context of liver metastases, providing a broad characterization of this process in different relevant scenarios, including cells growing in vitro in 2D and 3D, and in vivo. Results show that in vitro, only a subset of cancer cell lines are coherently strong or moderate competitors against hepatocytes, while the remaining demonstrate poor competitiveness. The competitive proficiency can vary depending on the experimental growth system that is employed, and often predicts the phenotype of liver metastases in terms of aggressiveness and morphology. Finally, our data point towards an involvement of mechanical competition in determining the supercompetitor trait of cancer cells. Altogether, our research provides the first comprehensive characterization of heterotypic cell competition, and indicates that cancer cells possess heterogeneous competitive proficiency towards hepatocytes which can be affected by the growth conditions.

cancer biology↗

bioRxiv2021

A conserved role of Parkinson-associated DJ-1 metabolites in sperm motility, mitosis, and embryonic development

Fertility rates in the developing world have dramatically dropped in the last decades. This drop is likely due to a decline in sperm quality and women having children at older ages. Loss of function mutations in DJ-1, a Parkinsons associated gene, are linked to alterations in multiple cellular processes such as mitochondrial activity, ROS production or sperm motility and lead to an early onset of Parkinsons disease and male infertility in humans and other species. Glycolate (GA) and D-lactate (DL), products of DJ-1 glyoxalase activity, sustain mitochondrial function and protect against environmental aggressions. We, therefore, tested whether these substances could also have a rescue effect on these phenotypes. Here, we show that DJ-1 loss of function not only affects sperm motility but also leads to defects in mitosis and an age-dependent increase in the abortion rate. Remarkably, whereas DL was only able to rescue embryonic lethality in C. elegans, GA rescued these phenotypes in all model systems tested and even increased sperm motility in wild-type sperm. These positive effects seem to be mediated through an increase in NAD(P)H production and the regulation of intracellular calcium. These findings not only strongly suggest GA as a new therapeutic candidate to improve male and female fertility but also show its potential to treat diseases associated with a decline in mitochondrial function or to improve mitochondrial function in aging.

developmental biology↗

bioRxiv2017

The ABC transporter Snu drives formation of the lipid-based inward and outward barrier in the skin of Drosophila

Lipids in extracellular matrices (ECM) contribute to barrier function and stability of epithelial tissues such as the pulmonary alveoli and the skin. In insects, skin waterproofness depends on the outermost layer of the extracellular cuticle termed envelope that contains cuticulin, an unidentified water-repellent complex molecule composed of proteins, lipids and catecholamines. Based on live-imaging analyses of fruit fly larvae, we find that initially envelope units are assembled within vesicles harbouring the ABC transporter Snu and the extracellular protein Snsl. In a second step, the content of these vesicles is distributed to cuticular lipid-transporting nanotubes named pore canals and to the cuticle surface in dependence of Snu function. Consistently, the surface of snu and snsl mutant larvae is depleted from lipids and cuticulin. By consequence, these animals suffer uncontrolled water loss and penetration of xenobiotics. Our data allude to a two-step model of envelope i.e. barrier formation. The proposed mechanism in principle parallels the events occurring during differentiation of the lipid-based ECM by keratinocytes in the vertebrate skin suggesting establishment of analogous mechanisms of skin barrier formation in vertebrates and invertebrates.

cell biology↗