LRP1 Methylation and Colon Cancer

Colorectal cancer (CRC) is a major public health problem in France and worldwide. CRC is the third most common cancer in incidence and mortality in France. The vast majority of these cancers are adenocarcinomas that arise sporadically and develop from precursor lesions: adenoma. All CRC with the same disease stage do not have the same prognosis. Various parameters have been identified as factors influencing the prognosis and allows adjustment of the treatment. The poor histoprognostic factors are vessels and nerves invasion by the tumor or the mucinous adenocarcinoma subtype. At the molecular level, the presence of microsatellite instability (MSI) improves the prognosis, while the presence of a BRAF mutation is an independent poor prognostic factor. The different molecular pathways of colonic carcinogenesis are the chromosomal instability pathway, the microsatellite instability pathway inducing errors in DNA mismatch repair and the CpG Island Methylator Phenotype (CIMP). The hypermethylation of CpG islands of genes promoters leads to an over or most frequently under gene expression. CIMP is observed in near 15% of CRC and is associated with specific clinical and pathological features: older patients, female predominance, right colonic involvement, poorly differentiated or mucinous adenocarcinomas. From a molecular point of view, the high CIMP phenotype is strongly associated with the presence of BRAFV600E mutation, the absence of RAS mutation and the presence of microsatellite instability. The prognostic value of CIMP is actually controversial. A recent meta-analysis found that the CIMP phenotype was associated with a poor prognosis. Methylation of some genes promoters as CDKN2A is associated with a poor prognosis. LRP-1 (low density lipoprotein receptor-related protein 1) is a multifunctional endocytic receptor that belongs to the LDL receptors the family. It mediates the clearance of many extracellular enzymes involved in the spread of cancer cells: metalloprote