Towards pathway-centric cancer therapies via pharmacogenomic profiling analysis of ERK signalling pathway

Genomic Sequencing and Insight into Clinical Heterogeneity and Prognostic Pathway Genes in Patients with Metastatic Colorectal Cancer

BACKGROUND

An understanding of signaling pathways has not been fully incorporated into prognostication and therapeutic options. We evaluated the hypothesis that information about cancer-related signaling pathways can improve prognostic stratification and explain some of the clinical heterogeneity in patients with metastatic colorectal cancer.

STUDY DESIGN

We analyzed prognostic relevance of signaling pathways in patients undergoing resection of colorectal liver metastases (CLM) from 2004-2017, and clinical actionability of gene alterations in 7 signaling pathways: p53, Wnt, RTK-RAS, PI3K, TGFβ, Notch, and cell cycle. To assess the wide applicability, the results were validated in an external retrospective cohort including patients with unresectable metastatic colorectal cancer.

RESULTS

Of 579 patients, the numbers of patients with pathway alterations were as follows: p53, n = 420 (72.5%); Wnt, 340 (58.7%); RTK-RAS, 333 (57.5%); PI3K, 110 (19.0%); TGFβ, 65 (11.2%); Notch, 41 (7.1%); and cell cycle, 15 (2.6%). More than 80% of alterations in each pathway occurred in a single predominant gene TP53, APC, KRAS, PIK3CA, FBXW7, and RB1 in p53, Wnt, RTK-RAS, PI3K, Notch, and cell cycle pathways, respectively. Alterations of 4 pathways (p53, RTK-RAS, TGFβ, and Notch) and corresponding predominant genes (TP53, RAS/BRAF, SMAD4, and FBXW7) were significantly associated with worse overall survival (OS), and alterations of Wnt pathway (APC) were associated with better OS in the median follow-up duration of 3.8 years. Similarly, in the external cohort, alterations of p53 (TP53) and RTK-RAS (RAS/BRAF) were significantly associated with worse OS, whereas alteration of Wnt (APC) was associated with better OS in the median follow-up duration of 2.6 years.

CONCLUSIONS

Genomic sequencing provides insights into clinical heterogeneity and permits finer prognostic stratification in patients with metastatic colorectal cancer.

New strategies for targeting drug combinations to overcome mutation-driven drug resistance

Targeted therapies are suggested as an effective alternative for patients with cancer that harbor mutations, but treatment outcomes are frequently limited by primary or acquired drug resistance. The present review describes potential mechanisms of primary or acquired drug resistances to provide a resource for considering how to be overcome. We focus on strategies of targeted drug combinations to minimize the development of drug resistance within the context how resistance develops. Strategies benefit from the combined use of "omics" technologies, i.e., high-throughput functional genomics data, pharmacogenomics, or genome-wide CRISPR-Cas9 screening, to analyze and design targeted drug combinations for mutation-driven drug resistance. We also introduce new insights towards pathway-centric combined therapies as an alternative to overcome the heterogeneity and benefit patient prognoses.