All the familial tumors sequenced harbored either a somatic mutation or loss of the wild-type allele.
While baseline genetic or IHC analysis can identify tumours with an appropriate genetic profile, e.g. PI3Kα mutation, PTEN mutation or loss, it is more challenging to determine whether pathway activation will be reduced by a particular drug.
Mutation or loss of stoichiometry of at least one of the members may potentially lead to cancer development.
Mutation or loss of ATM or ATR lead to cell senescence, accelerated aging, and premature death associated with increased genomic instability [12], [13].
A large proportion of human cancers exhibit dysregulation of p53 function (e.g. by p53 mutation or loss of p53 expression) and therefore are unable to activate transcription of the CDK inhibitor, p21, which is required for arrest in G1.
von Hippel-Lindau (VHL) disease is an autosomal dominant familial cancer syndrome caused by germline mutation or loss of the VHL tumor suppressor gene that affects approximately 1 in 36,000 individuals [1].
The PI3K/Akt signaling pathway can be upregulated in gliomas through several mechanisms, most commonly through mutation or loss of heterozygosity of PTEN or through amplification/over-expression of critical growth factor receptors such as EGFR and PDGFR.
Mutation or loss of one such susceptibility factor may result in virus resistance.
Studies show that mutation or loss of a single allele may be sufficient to exert diseased cellular phenotypes.
In over half of human cancers, p53 is inactivated due to either point mutation or loss of p53 gene.
However, impairment of functional p53, either by mutation or loss of expression, is frequently detected in cancer.
