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Rovini, A.

Publications and source records attributed to Rovini, A..

2 recordsLinked to original sources
bioRxiv2024

Predicting Tumor Mutational Burden from UHF-Dielectrophoresis Crossover Frequency

Tumor Mutational Burden (TMB) has emerged as a crucial biomarker to guide patient eligibility for immunotherapy. However, whole exome sequencing, the gold-standard method for TMB measurement, remains limited in accessibility due to its high costs, operational complexity, and lengthy processing times. To address these limitations, we investigated whether Ultra-High-Frequency (UHF) technology could serve as a novel approach to assess TMB by analyzing the crossover frequencies or electromagnetic signature (EMS) of cancer cells on a lab-on-a-chip biosensor, integrating microfluidics and dielectrophoresis. In a panel of 12 cancer cell lines with varying TMB levels, we observed that EMS showed an upward shift correlating with higher TMB, particularly in solid tumor cell lines. This finding suggests a potential relationship between TMB and EMS. To further explore this hypothesis, we artificially increased mutation levels by treating cells with the highly mutagenic compound N-ethyl-N-nitrosourea (ENU). Results showed that EMS captured significant TMB variations in ENU-treated cells with enhanced proliferative capacity compared to their parental counterparts. These results underscore the importance of matched control samples for reliable EMS measurements. Altogether, our findings highlight the potential of EMS to detect TMB variations associated with proliferative activity, a key hallmark of cancer cells, thereby enabling a more precise stratification of cancer cells. HighlightsO_LIWe propose a new biosensor to improve patient stratification for ICI eligibility C_LIO_LIHigh frequency fields and dielectric spectroscopy can estimate TMB in cancer cells C_LIO_LISignificant changes in UHF-DEP signatures correlate with varying TMB levels C_LIO_LIUHF-DEP provides a cheap, rapid and label-free method to predict ICI response C_LIO_LIOffers an innovative and complementary marker to conventional diagnostic approaches C_LI Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=92 SRC="FIGDIR/small/622085v1_ufig1.gif" ALT="Figure 1"> View larger version (22K): org.highwire.dtl.DTLVardef@703983org.highwire.dtl.DTLVardef@1cfdf46org.highwire.dtl.DTLVardef@4b9285org.highwire.dtl.DTLVardef@1809255_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗
bioRxiv2022

Restricting α-Synuclein Transport into Mitochondria by Inhibition of α-Synuclein-VDAC Complexation as a Potential Therapeutic Target for Parkinson's Disease Treatment

Involvement of alpha-synuclein (Syn) in Parkinsons disease (PD) is complicated and difficult to trace on cellular and molecular levels. Recently we established that Syn can regulate mitochondrial function by voltage-activated complexation with the Voltage-Dependent Anion Channel (VDAC) of the outer mitochondrial membrane. When complexed with Syn, the VDAC pore is partially blocked, reducing the transport of ATP/ADP and other metabolites. Further, Syn can translocate into the mitochondria through VDAC, where it interferes with mitochondrial respiration. Recruitment of Syn to the VDAC-containing lipid membrane appears to be a crucial prerequisite for both the blockage and translocation processes. Here we report an inhibitory effect of HK2p, a small membrane-binding peptide from the mitochondria-targeting N-terminus of hexokinase 2, on the Syn membrane binding, and hence on Syn complex formation with VDAC and translocation through it. In electrophysiology experiments, addition of HK2p at micromolar concentrations to the same side of the membrane as Syn results in dramatic reduction of the frequency of blockage events in a concentration-dependent manner, reporting on complexation inhibition. Using two complementary methods of measuring protein-membrane binding, bilayer overtone analysis and fluorescence correlation spectroscopy, we found that HK2p induces detachment of Syn from lipid membranes. Experiments with live HeLa cells using proximity ligation assay confirmed that HK2p impedes Syn entry into mitochondria. Our results demonstrate that it is possible to regulate Syn-VDAC complexation by a rationally designed peptide, thus suggesting new avenues in the search for peptide therapeutics to alleviate Syn mitochondrial toxicity in PD and other synucleinopathies.

biophysics↗