Oregon Health and Science University – 2

Large-scale Characterization of Drug Responses for Clinically Relevant Proteins in Cancer Cell Lines

The study profiles the protein-level responses of a large collection of cancer cell lines to drug perturbations using reverse-phase protein arrays and builds a systematic protein-drug connectivity map.

The results show that integrating perturbed protein responses provides better prediction of drug sensitivity and insights into drug resistance mechanisms and combination therapies.

In Vivo Functional Characterization of EGFR Variants Identifies Novel Drivers of Glioblastoma

In an effort to validate novel functional EGFR variants and pathways, we screen a library of missense mutations of EGFR and found that different variants differentially drive gliomagenesis. Among the differentially activated pathways was lipid metabolism, and perturbation of this pathway delayed glioma-associated death in mouse models.

Experimental Approaches

Tumor bearing mice were generated through in utero electroporation. A construct expressing CRISPR guide sequences that targeted mouse Tp53 and Pten, along with the Cas9 ORF were injected and electroporated into the lateral ventricles of E14.5 mouse brains. Gliomas driven by different EGFR variants were generated by electroporating and piggyBac transposases construct along with a transposable cassette expressing EGFR variants under a constitutively active promoter. When mice demonstrated behaviors characteristic of tumor burden, bulk tumor tissue were dissected. Form these tissue samples, RNA was extracted using Qiagen’s RNeasy Plus Mini Kit. 700ng of RNA was used as template for library preparation using the TruSeq Stranded mRNA LT kit. Using at least 3 biological replicates, pooled libraries were sequenced with approximately 20 million pair-end (2x75) reads per sample using Illumina’s Mid Output v2 kit on a NextSeq500. FASTQ files were quality controlled using fastQC (v0.10.1) and MultiQZ (v0.9), and aligned to the mm10 reference genome.

Tumor-intrinsic SIRPA Promotes Sensitivity to Checkpoint Inhibition Immunotherapy in Melanoma

The study reveals that tumor-intrinsic SIRPA can enhance the sensitivity to anti- PD-1 treatment in melanoma patients, whereas macrophage SIRPA has a well-established role as a major inhibitory modulator in antitumor immunity. The results highlight that the same target in different cell types can have antagonistic effects on immunotherapy.