It is known that c-Myb expression can be modified by the estrogen receptor, and c-Myb protein levels are increased in ER+ tumors [18], [34], [35].
Although TGF-β receptors are found to be modified by phosphorylation, ubiqitination and sumoylation, whether the receptors also undergo other post-translational modifications, such as acetylation, neddylation, PARylation and others is still an open question.
Previous research implied that the activity of this receptor may be modified by exposure to a peptide fragment derived from the C-terminal region of the enzyme acetylcholinesterase.
However, following gene duplication, the binding properties of an OR gene (or any receptor) may be modified by a few changes to the binding site.
Rare alleles at HRAS1 were found to increase risk of ovarian cancer in BRCA1 carriers, whereas breast cancer risk has been found to be modified by rare alleles at the androgen receptor.
In addition, recent reports provide evidence that breast cancer risk from smoking may be modified by other factors including the hormone receptor status of the tumor [23], metabolite enzyme genes [24]– [27], familial history of breast cancer [6], and exogenous hormone use [8], [28].
TLR-elicited functions can also be modified by co-engagement of non-TLR receptors.
For instance, the affinity of the Fc domain to Fc receptors can be modified by changing the sugar structures on antibodies (glyco-engineering) [ 69].
Additionally, following proper protein folding, glycan moieties can be modified by branching, which has been related to receptor signalling (Partridge et al. 2004) and cancer development (Dube and Bertozzi 2005).
Recently, the effect of passive smoking on asthma phenotypes in children was also reported to be modified by polymorphisms in the β 2-adrenergic receptor (ADRB2) gene (Zhang et al. 2007), which supports previously observations in adults (Wang et al. 2001).
