scholarly journals AfterhMSH2 andhMLH1?what next? Analysis of three-generational, population-based, early-onset colorectal cancer families

2002 ◽  
Vol 102 (2) ◽  
pp. 166-171 ◽  
Author(s):  
Mark A. Jenkins ◽  
Laura Baglietto ◽  
Gillian S. Dite ◽  
Damien J. Jolley ◽  
Melissa C. Southey ◽  
...  
2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Giulia Magnani ◽  
Daniela Furlan ◽  
Nora Sahnane ◽  
Luca Reggiani Bonetti ◽  
Federica Domati ◽  
...  

Colorectal cancer is usually considered a disease of the elderly. However, a small fraction of patients develops colorectal cancer earlier. The aim of our study was to define the frequency of known hereditary colorectal syndromes and to characterise genetic and epigenetic features of early nonhereditary tumors. Thirty-three patients ≤40 years with diagnosis of colorectal cancer and 41 patients with disease at >60 years of age were investigated for MSI, Mismatch Repair proteins expression,KRASandBRAFmutations, hypermethylation, and LINE-1 hypomethylation. Detection of germline mutations was performed in Mismatch Repair,APCandMUTYHgenes. Early onset colorectal cancer showed a high incidence of hereditary forms (18%).KRASmutations were detected in 36% of early nonhereditary tumors. Early onset colorectal cancer disclosed an average number of methylated genes significantly lower when compared to the controls (p=0.02). Finally both of the two groups were highly methylated inESR1,GATA5, andWT1genes and were similar for LINE-1 hypomethylation. The genetic make-up of carcinomas differs from young to elderly patients. Early onset tumors showed more frequently a constitutional defective of Mismatch Repair System and a minor number of methylated genes. Hypermethylation ofESR1,GATA5, andWT1genes suggests possible markers in the earlier diagnosis of colorectal tumorigenesis.


2020 ◽  
Vol 158 (6) ◽  
pp. S-496
Author(s):  
Arif A. Arif ◽  
Daljeet Chahal ◽  
Caroline Speers ◽  
Mary A. De Vera ◽  
Sharlene Gill ◽  
...  

Author(s):  
Jeong Eun Kim ◽  
Jaeyong Choi ◽  
Chang-Ohk Sung ◽  
Yong Sang Hong ◽  
Sun Young Kim ◽  
...  

AbstractThe global incidence of early-onset colorectal cancer (EO-CRC) is rapidly rising. However, the reason for this rise in incidence as well as the genomic characteristics of EO-CRC remain largely unknown. We performed whole-exome sequencing in 47 cases of EO-CRC and targeted deep sequencing in 833 cases of CRC. Mutational profiles of EO-CRC were compared with previously published large-scale studies. EO-CRC and The Cancer Genome Atlas (TCGA) data were further investigated according to copy number profiles and mutation timing. We classified colorectal cancer into three subgroups: the hypermutated group consisted of mutations in POLE and mismatch repair genes; the whole-genome doubling group had early functional loss of TP53 that led to whole-genome doubling and focal oncogene amplification; the genome-stable group had mutations in APC and KRAS, similar to conventional colon cancer. Among non-hypermutated samples, whole-genome doubling was more prevalent in early-onset than in late-onset disease (54% vs 38%, Fisher’s exact P = 0.04). More than half of non-hypermutated EO-CRC cases involved early TP53 mutation and whole-genome doubling, which led to notable differences in mutation frequencies between age groups. Alternative carcinogenesis involving genomic instability via loss of TP53 may be related to the rise in EO-CRC.


Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3857
Author(s):  
Pilar Mur ◽  
Nuria Bonifaci ◽  
Anna Díez-Villanueva ◽  
Elisabet Munté ◽  
Maria Henar Alonso ◽  
...  

A large proportion of familial and/or early-onset cancer patients do not carry pathogenic variants in known cancer predisposing genes. We aimed to assess the contribution of previously validated low-risk colorectal cancer (CRC) alleles to familial/early-onset CRC (fCRC) and to serrated polyposis. We estimated the association of CRC with a 92-variant-based weighted polygenic risk score (wPRS) using 417 fCRC patients, 80 serrated polyposis patients, 1077 hospital-based incident CRC patients, and 1642 controls. The mean wPRS was significantly higher in fCRC than in controls or sporadic CRC patients. fCRC patients in the highest (20th) wPRS quantile were at four-fold greater CRC risk than those in the middle quantile (10th). Compared to low-wPRS fCRC, a higher number of high-wPRS fCRC patients had developed multiple primary CRCs, had CRC family history, and were diagnosed at age ≥50. No association with wPRS was observed for serrated polyposis. In conclusion, a relevant proportion of mismatch repair (MMR)-proficient fCRC cases might be explained by the accumulation of low-risk CRC alleles. Validation in independent cohorts and development of predictive models that include polygenic risk score (PRS) data and other CRC predisposing factors will determine the implementation of PRS into genetic testing and counselling in familial and early-onset CRC.


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