PURPOSE: PIK3CA and PTEN mutations are prevalent in colorectal cancer and potential markers of response to mitogen-activated protein/extracellular signal-regulated kinase inhibitors and anti-EGF receptor antibody therapy. Relationships between phosphoinositide 3-kinase (PI3K) pathway mutation, clinicopathologic characteristics, molecular features, and prognosis remain controversial. EXPERIMENTAL DESIGN: A total of 1,093 stage I-IV colorectal cancers were screened for PIK3CA (exons 9 and 20), KRAS (codons 12-13), BRAF (codon 600) mutations, and microsatellite instability (MSI). PTEN (exons 3-8) and CpG island methylator phenotype (CIMP) status were determined in 744 and 489 cases. PIK3CA data were integrated with 17 previous reports (n = 5,594). RESULTS: PIK3CA and PTEN mutations were identified in 11.9% and 5.8% of colorectal cancers. PTEN mutation was associated with proximal tumors, mucinous histology, MSI-high (MSI-H), CIMP-high (CIMP-H), and BRAF mutation (P < 0.02). PIK3CA mutation was related to older age, proximal tumors, mucinous histology, and KRAS mutation (P < 0.04). In integrated cohort analysis, PIK3CA exon 9 and 20 mutations were overrepresented in proximal, CIMP-low (CIMP-L), and KRAS-mutated cancers (P ≤ 0.011). Comparing PIK3CA exonic mutants, exon 20 mutation was associated with MSI-H, CIMP-H, and BRAF mutation, and exon 9 mutation was associated with KRAS mutation (P ≤ 0.027). Disease-free survival for stage II/III colorectal cancers did not differ by PI3K pathway status. CONCLUSION: PI3K pathway mutation is prominent in proximal colon cancers, with PIK3CA exon 20 and PTEN mutations associated with features of the sessile-serrated pathway (MSI-H/CIMP-H/BRAF(mut)), and PIK3CA exon 9 (and to a lesser extent exon 20) mutation associated with features of the traditional serrated pathway (CIMP-L/KRAS(mut)) of tumorigenesis. Our data highlight the PI3K pathway as a therapeutic target in distinct colorectal cancer subtypes.
PURPOSE:PIK3CA and PTEN mutations are prevalent in colorectal cancer and potential markers of response to mitogen-activated protein/extracellular signal-regulated kinase inhibitors and anti-EGF receptor antibody therapy. Relationships between phosphoinositide 3-kinase (PI3K) pathway mutation, clinicopathologic characteristics, molecular features, and prognosis remain controversial. EXPERIMENTAL DESIGN: A total of 1,093 stage I-IV colorectal cancers were screened for PIK3CA (exons 9 and 20), KRAS (codons 12-13), BRAF (codon 600) mutations, and microsatellite instability (MSI). PTEN (exons 3-8) and CpG island methylator phenotype (CIMP) status were determined in 744 and 489 cases. PIK3CA data were integrated with 17 previous reports (n = 5,594). RESULTS:PIK3CA and PTEN mutations were identified in 11.9% and 5.8% of colorectal cancers. PTEN mutation was associated with proximal tumors, mucinous histology, MSI-high (MSI-H), CIMP-high (CIMP-H), and BRAF mutation (P < 0.02). PIK3CA mutation was related to older age, proximal tumors, mucinous histology, and KRAS mutation (P < 0.04). In integrated cohort analysis, PIK3CA exon 9 and 20 mutations were overrepresented in proximal, CIMP-low (CIMP-L), and KRAS-mutated cancers (P ≤ 0.011). Comparing PIK3CA exonic mutants, exon 20 mutation was associated with MSI-H, CIMP-H, and BRAF mutation, and exon 9 mutation was associated with KRAS mutation (P ≤ 0.027). Disease-free survival for stage II/III colorectal cancers did not differ by PI3K pathway status. CONCLUSION: PI3K pathway mutation is prominent in proximal colon cancers, with PIK3CA exon 20 and PTEN mutations associated with features of the sessile-serrated pathway (MSI-H/CIMP-H/BRAF(mut)), and PIK3CA exon 9 (and to a lesser extent exon 20) mutation associated with features of the traditional serrated pathway (CIMP-L/KRAS(mut)) of tumorigenesis. Our data highlight the PI3K pathway as a therapeutic target in distinct colorectal cancer subtypes.
Authors: F Jeroen Vogelaar; Felice N van Erning; Marlies S Reimers; Hans van der Linden; Hans Pruijt; Adriaan J C van den Brule; Koop Bosscha Journal: Mol Med Date: 2016-05-09 Impact factor: 6.354
Authors: Stacey A Cohen; Emily H Turner; Mallory B Beightol; Angela Jacobson; Ted A Gooley; Stephen J Salipante; Sigurdis Haraldsdottir; Christina Smith; Sheena Scroggins; Jonathan F Tait; William M Grady; Edward H Lin; David E Cohn; Paul J Goodfellow; Mark W Arnold; Albert de la Chapelle; Rachel Pearlman; Heather Hampel; Colin C Pritchard Journal: Gastroenterology Date: 2016-06-11 Impact factor: 22.682
Authors: Shuji Ogino; Xiaoyun Liao; Yu Imamura; Mai Yamauchi; Nadine J McCleary; Kimmie Ng; Donna Niedzwiecki; Leonard B Saltz; Robert J Mayer; Renaud Whittom; Alexander Hantel; Al B Benson; Rex B Mowat; Donna Spiegelman; Richard M Goldberg; Monica M Bertagnolli; Jeffrey A Meyerhardt; Charles S Fuchs Journal: J Natl Cancer Inst Date: 2013-11-14 Impact factor: 13.506