Diacylglycerol Signaling

22 PKCd as a Target for Chemotherapeutic Drugs
Moreover, PKCd plays a role in determining the response to tumor cells to a variety
of chemotherapeutic drugs. Therefore, PKCd may be an attractive therapeutic
target in many types of cancers. Limitations to the use of PKCd as a therapeutic
target include its ubiquitous expression and its diverse effects in a given cellular
system. Thus, targeting PKCd may decrease cell invasion and sensitize tumor cells
to chemotherapy along with concomitantly increasing cell proliferation. Thus, an
alternative approach for inhibiting PKCd activity or expression may be the inhibition
of specific functions of PKCd by either interfering with a specific substrate,
blocking translocation to a specific subcellular site, or inhibiting the phosphorylation
of PKCd on a distinct tyrosine residue that specifically mediates the distinct
effect of this isoform. Additional studies are required to identify molecular switches
that finely control the ability of PKCd to exert distinct effects in tumor cells and
inhibitors that can selectively target these effects.
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