Target Classes  Signaling Molecules  The signals from cell
surface receptors to downstream molecules within a cell make for
a complex system. One molecule can elicit multiple activities
that branch outward through numerous pathways, many of which
intersect and influence one another in ways that are difficult
to predict or decipher.  With recent advances in higher-
throughput platforms as well as computing power, pathway
analysis research is contributing significantly to a better
understanding of the physiologic matrix underlying disease
conditions. Researchers are also leveraging this approach to
identify potential new targets for treating disease as well as
for creating more detailed maps of receptor mechanisms.  By
studying pathway analysis to understand the routes through which
drugs act on a system rather than simply focusing on a specific
target, researchers attain a better understanding of how a
particular disease develops and progresses.  With an expanded
knowledge of cellular pathways, researchers can