Personalized medicine in colorectal cancer

Abstract

Colorectal cancer (CRC) is a heterogeneous disease with various genetic and epigenetic factors leading to difficulties in response to both the therapy and drug resistance. Moreover, even in tumors with similar histopathological characteristics, different responses and molecular features could be observed because of the genetic basis and its interactions with the living environment. Through personalized medicine, we can classify patients into separate groups according to their genetic and epigenetic features and their susceptibility for a specific disease which could help with choosing the best therapeutic approach. In this review, genetic and epigenetic factors that cause heterogeneity in colorectal cancer are evaluated and proper drug administration in both chemotherapy and target therapy are suggested.

Keywords: Biomarker; Chemotherapy; Colorectal cancer; Personalized medicine; Targeted therapy.

Figure 1

All cell signaling pathways blocked by targeted drugs such as Cetuximab which is a monoclonal antibody for blocking epidermal growth factor receptor. Thus, survival, proliferation, migration, invasion, and angiogenesis of cancer cells can be inhibited. Resistance to these drugs is as a result of a mutation in one of the involved genes in these cell signaling

Figure 2

Fluoropyrimidines family cause cellular death through inducing disturbance in DNA duplication and transcription

Figure 3

Oxaliplatin is a compound that produces cross-linkages in DNA. This defect can be repaired by MMR system and NER mechanism. Irinotecan effect on duplication and transcription by inhibiting topoisomerase I enzyme