4 research outputs found
In Silico Identification and Biological Evaluation of Novel Selective Serum/Glucocorticoid-Inducible Kinase 1 Inhibitors Based on the Pyrazolo-Pyrimidine Scaffold
The
serum/glucocorticoid-inducible kinase 1 (Sgk1) has demonstrated
antiapoptotic function and the capability to regulate cell survival,
proliferation, and differentiation. A pivotal role of Sgk1 in carcinogenesis
and in resistance to anticancer therapy has been suggested. With the
aim of identifying new Sgk1 modulators, 322 pyrazolo-pyrimidine derivatives
have been virtually screened with respect to a crystallographic model
of Sgk1. The top five ranked compounds have been evaluated demonstrating
Sgk1 inhibition in vitro and selectivity compared to RAC-alpha serine/threonine-protein
kinase (Akt1)
Combining X‑ray Crystallography and Molecular Modeling toward the Optimization of Pyrazolo[3,4‑<i>d</i>]pyrimidines as Potent c‑Src Inhibitors Active in Vivo against Neuroblastoma
c-Src
is a tyrosine kinase belonging to the Src-family kinases.
It is overexpressed and/or hyperactivated in a variety of cancer cells,
thus its inhibition has been predicted to have therapeutic effects
in solid tumors. Recently, the pyrazolo[3,4-<i>d</i>]pyrimidine <b>3</b> was reported as a dual c-Src/Abl inhibitor. Herein we describe
a multidisciplinary drug discovery approach for the optimization of
the lead <b>3</b> against c-Src. Starting from the X-ray crystal
structure of c-Src in complex with <b>3</b>, Monte Carlo free
energy perturbation calculations were applied to guide the design
of c-Src inhibitors with improved activities. As a result, the introduction
of a <i>meta</i> hydroxyl group on the C4 anilino ring was
computed to be particularly favorable. The potency of the synthesized
inhibitors was increased with respect to the starting lead <b>3</b>. The best identified compounds were also found active in the inhibition
of neuroblastoma cell proliferation. Furthermore, compound <b>29</b> also showed in vivo activity in xenograft model using SH-SY5Y cells
Design, Synthesis, and Biological Evaluation of Pyrazolo[3,4‑<i>d</i>]pyrimidines Active in Vivo on the Bcr-Abl T315I Mutant
Starting from our in-house library
of pyrazolo[3,4-<i>d</i>]pyrimidines, a cross-docking simulation
was conducted on Bcr-Abl
T315I mutant. Among the selected compounds (<b>2a</b>–<b>e</b>), the 4-bromo derivative <b>2b</b> showed the best
activity against the Bcr-Abl T315I mutant. Deeper computational studies
highlighted the importance of the bromine atom in the para position
of the N1 side chain phenyl ring for the interaction with the T315I
mutant. A series of 4-bromo derivatives was thus synthesized and biologically
evaluated. Compound <b>2j</b> showed a good balance of different
ADME properties, high activity in cell-free assays, and a submicromolar
potency against T315I Bcr-Abl expressing cells. In addition, it was
converted into a water-soluble formulation by liposome encapsulation,
preserving a good activity on leukemic T315I cells and avoiding the
use of DMSO as solubilizing agent. In vivo studies on mice inoculated
with 32D-T315I cells and treated with <b>2j</b> showed a more
than 50% reduction
in tumor volumes
Prodrugs of Pyrazolo[3,4‑<i>d</i>]pyrimidines: From Library Synthesis to Evaluation as Potential Anticancer Agents in an Orthotopic Glioblastoma Model
Pyrazolo[3,4-<i>d</i>]pyrimidines
are potent protein
kinase inhibitors with promising antitumor activity but suboptimal
aqueous solubility, consequently worth being further optimized. Herein,
we present the one-pot two-step procedure for the synthesis of a set
of pyrazolo[3,4-<i>d</i>]pyrimidine prodrugs (<b>1a</b>−<b>8a</b> and <b>9a</b>−<b>e</b>) with higher aqueous solubility and enhanced pharmacokinetic and
therapeutic properties. ADME studies demonstrated for the most promising
prodrugs a better aqueous solubility, a favorable hydrolysis in human
and murine serum, and an increased ability to cross cell membranes
with respect to the parental drugs, explaining their better 24 h <i>in vitro</i> cytotoxicity against human glioblastoma U87 cell
line. Finally, the <b>4–4a</b> couple of drug/prodrug
was also evaluated <i>in vivo</i>, revealing a profitable
pharmacokinetic profile of the prodrug associated with a good efficacy.
The application of the prodrug approach demonstrated to be a successful
strategy for improving aqueous solubility of the parental drugs, determining
a positive impact also in their biological efficacy