Carbon nanotubes are remarkable solid-state nanomaterials that has spawned tremendous research interest in the area of sensing, actuation and biomedical nanotechnologies. At 1 nm in diameter and more than microns in length, nanotubes have been known to possess extraordinary mechanical strength, high thermal conductivity, unique electrical conductivity and biocompatibility. In this talk I will be focusing on our present research of nanotubes in sensing, actuation and cancer therapeutics. The science, properties and potential applications of carbon nanotubes in the micro-electro-mechanical systems (MEMS) and micro-opto-mechanical systems (MOMS), nanotube electronic devices to detect molecular signatures in cancer cells, and the opto-thermal properties of nanotubes for cancer therapeutics will be presented