JAK2 is dispensable for maintenance of JAK2 mutant B-cell acute lymphoblastic leukemias.

Activating JAK2 point mutations are implicated in the pathogenesis of myeloid and lymphoid malignancies, including high-risk B-cell acute lymphoblastic leukemia (B-ALL). In preclinical studies, treatment of JAK2 mutant leukemias with type I JAK2 inhibitors (e.g.

Gateway synthesis of daphnane congeners and their protein kinase C affinities and cell-growth activities.

The daphnane diterpene orthoesters constitute a structurally fascinating family of natural products that exhibit a remarkable range of potent biological activities. Although partial activity information is available for some natural daphnanes, little information exists for non-natural congeners or on how changes in structure affect mode of action, function, potency or selectivity. A gateway strategy designed to provide general synthetic access to natural and non-natural daphnanes is described and utilized in the synthesis of two novel members of this class.

Quantitation of cellular and topical uptake of luciferin-oligoarginine conjugates.

A major challenge confronting the further advancement of using molecular transporters conjugated to small molecular weight therapeutics in the clinic is the development of linkers that would allow for the controllable release of a free drug/probe only after cell entry. Development of assays that would allow for the rapid real-time quantification of transporter conjugate uptake and cargo release in cells and animals would greatly help in their development. In this chapter, we describe a imaging method that quantitatively measures transporter conjugate uptake and cargo release in real-time in both cell culture and animal models.

The design of guanidinium-rich transporters and their internalization mechanisms.

The ability of a drug or probe to cross a biological barrier has historically been viewed to be a function of its intrinsic physical properties. This view has largely restricted drug design and selection to agents within a narrow log P range. Molecular transporters offer a strategy to circumvent these restrictions.

Real-time analysis of uptake and bioactivatable cleavage of luciferin-transporter conjugates in transgenic reporter mice.

Many therapeutic leads fail to advance clinically because of bioavailability, selectivity, and formulation problems. Molecular transporters can be used to address these problems. Molecular transporter conjugates of otherwise poorly soluble or poorly bioavailable drugs or probes exhibit excellent solubility in water and biological fluids and at the same time an enhanced ability to enter tissues and cells and with modification to do so selectively.

Releasable luciferin-transporter conjugates: tools for the real-time analysis of cellular uptake and release.

The design, synthesis, and evaluation of conjugates of arginine-rich transporters and luciferin are described that release luciferin only after entry into cells that are stably transfected with luciferase. Each molecule of free luciferin that is released after entry generates a photon that can be measured allowing for real-time quantification of uptake and release in cells. The process provides a method to assay uptake and release of free luciferin as a function of variations in the releasable linker and in the transporter.