Quantification of histone H3 methylation after NSD2 knockdown
To monitor the specific activity of our target NSD2 we needed a readout for quantification of dimethylation of histone H3 at position Lysine 36.
We chose the human tumor cell line U-2 OS due to a relatively high expression of endogenous NSD2 protein. Three siRNA molecules were used for NSD2 knockdown and dimethylation of lysine 36 on histone 3 (H3K36me2) was quantified via a specific antibody in Western Blot analysis.
Three siRNA molecules siWHSC1 A-C were incubated with U-2OS cells for 72 hours before cell lysis and subjection to SDS-PAGE and Western Blot analysis to quantify NSD2 expression (A), quantify Histone H3 and H3K36me2 to detect the activity of methyltransferase NSD2 (B, C).
High-throughput screening with nucleosome substrate identifies small-molecule inhibitors of the human histone lysine methyltransferase NSD2
Confirmation of the mode of action of a PI3K inhibitor
To gain insight into the global phenotypic effects of a novel inhibitor that was presumed to act through inhibition of PIK3.
We performed a large cell panel screen, the ProliFiler assay, to determine IC50 values of the inhibitor impacting cellular proliferation on 140 human tumor cell lines. We correlated the resulting sensitivity profile of the assumed PI3K inhibitor with that of more than 1000 cancer drugs with a known mode of action. The computational analysis was performed with the MoA Finder service by our partner CRO 4HF Biotec.
The volcano blot shows the correlation between our PI3K inhibitor and more than 1000 cancer drugs in the 4HF Biotec Cancer Data Mining database.
The cancer drugs that resemble our compounds' profile mostly comprise PI3K inhibitors confirming that inhibition of PI3K causes the phenotype.