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Background: Integrated analysis of multi-omic data is important in understanding oncogenesis, pathology, and drug mechanism of action. Formalin-fixed, paraffin-embedded (FFPE) tissues comprise the bulk of archival specimens in hospitals and clinical trials. Commercial kits are commonly used to extract RNA, DNA, or protein for biomarker studies; however, high-quality extractions are challenging due to crosslinking. We explored the feasibility of performing proteomic, transcriptomic, and genetic analysis from limited FFPE samples collected in clinical trials through a pilot study in colorectal cancer (CRC) and normal tissue. Methods: Qiagen kits were employed, with some modifications, to extract nucleic acid and protein from FFPE sample lysates that would be amenable to next-generation sequencing and liquid chromatography/mass-spectrometry (LC/MS) proteomic profiling. Commercially sourced FFPE slides from CRC biopsies and normal colon, heart, and skin samples were processed (n = 10 each; ~600-mm2 by 5-μm/slice). RNA-seq library preparation was performed using the Illumina® TruSeq Access kit. Label-free LC/MS proteomic analysis was carried out using trypsin/Lys-C-digested protein fragments on an EASY-nLC™ 1200 coupled to a Q Exactive™ Plus (Thermo Fisher). MS data were processed with MaxQuant to estimate protein abundance (Cox and Mann, Nat Biotech 2008). Results: Of 40 samples tested, 38 yielded quantifiable nucleic acid and protein of sufficient quality for transcriptional and proteomic analyses. Mean RNA yield was ~300 ng (150 ng-1.2 µg). RNA degradation was significant, with a mean DV>200 of 45% (Agilent Bioanalyzer). Mean DNA yield was 530 ng, with a mean fragment size of 2 kb. Mean protein yield was 50 µg (1 µg-300 µg). RNA libraries had a mapping rate range of 85%-90% and a coding rate range of 70%-80%; ~16,000 genes were reliable detected (log2 TPM > 1). The number of unique proteins detected ranged from 3,000 to 4,000 for CRC, normal colon, and heart samples; skin samples averaged 1,000 proteins and had the lowest overall yield. Correlation of RNA and protein expression for the same genes was weak (Spearman's rho ~0.3-0.4) at the per-sample level but statistically significant. Using linear models, we identified differentially expressed transcripts and proteins between the CRC and normal colon samples. Pathway enrichment analysis of both modalities indicated changes in cell cycle, which is consistent with rapid growth of tumor cells. Changes in nucleoside metabolism, extracellular matrix remodeling, and innate immune response were more apparent at the protein level. Conclusion: We found that multi-omic analysis was feasible with FFPE samples, and proteomics can be used to validate RNA results. Additionally, proteomics reveal post-translational events, such as extracellular matrix remodeling, that provide unique insights into cancer pathology. Citation Format: Vishal Patel, Ji Gao, Mingyi Liu, Aiqing He, Xi-Tao Wang, Kathryn Vanderlaag, Ariella Sasson, Stefan Kirov, Sunil Kuppasani, Omar J. Jabado, Kandasamy Ravi, Ashok Dongre, Julie Carman, Heidi LeBlanc. Integrated analysis of colorectal carcinoma by co-extraction of RNA, DNA and protein from FFPE tumor samples [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 2707.

The CK2 protein kinases are a small family of two highly related serine/threonine kinases composed of two catalytic subunits, α and α’, and a single β subunit. Numerous substrates have been reported for CK2 and these proteins are known to participate in diverse cellular processes, including cell signaling, transcription, DNA repair, apoptosis regulation and tumor suppression. Elevated CK2 expression and kinase activity has been observed in many cancer types. Further, mRNA knockdown and enzyme inhibition studies have demonstrated that many cancer cell lines are dependent on CK2 for growth and survival. To further evaluate CK2 kinases as targets for therapeutic intervention in cancer, we identified BMS-595, a potent and selective, ATP-competitive CK2 inhibitor. BMS-595 inhibits the in vitro proliferation of human colorectal and lung cancer cell lines with IC50s ranging from less than 10 nM to greater than 1 μM. In sensitive cell lines, anti-proliferative effects of BMS-595 and structurally related analogs strongly correlated with cellular CK2 kinase inhibition. Oral administration of BMS-595 to mice bearing colorectal cancer and lung cancer xenografts demonstrated pharmacodynamic effects and robust efficacy at tolerated doses. These studies confirm the dependence of a subset of human colon and lung cancer cell lines on CK2 activity for growth and demonstrate that pharmacologic inhibition of CK2 can produce anti-tumor efficacy at tolerated doses. Citation Format: Brent A. Rupnow, Chiang Yu, Jonathan G. Pabalan, Urvashi V. Roongta, Jonathan S. Lippy, Ashok R. Dongre, Mary T. Obermeier, Aberra Fura, Paul A. Elzinga, Benjamin J. Henley, Joseph Fargnoli, Francis Y. Lee, William R. Foster, Christine M. Tarby, Brian E. Fink, John S. Tokarski, Ashvinikumar V. Gavai, Tai W. Wong, John T. Hunt, Gregory D. Vite, Ashok V. Purandare. Anti-tumor activity of BMS-595, a novel CK2 kinase inhibitor. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5395. doi:10.1158/1538-7445.AM2015-5395