Imatinib treatment inhibit IL-6, IL-8, NF-KB and AP-1 production and modulate intracellular calcium in CML patients.

Imatinib (IM) is considered the gold standard for chronic myeloid leukemia (CML) treatment, although resistance is emerging as a significant problem. The proinflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8) play an important role in cell proliferation, survival, and resistance to glucocorticoid-mediated cell death. Several transcription factors such as NF-KB and AP-1 are activated in response to physiopathological increases and modulation of intracellular calcium levels. Our previous study demonstrated that lymphocytes from CML patients showed dysregulated calcium homeostasis and oxidative stress. Alteration in ionized calcium concentration in the cytosol has been implicated in the initiation of secretion, contraction, and cell proliferation. In this study, we hypothesized that IL-6, IL-8, NF-kB, AP-1, and intracellular calcium may be used as selective and prognostic factors to address the follow-up in CML patients treated with imatinib. Our results demonstrated a significant down-regulation in IL-6 and IL-8 release as well as NF-kB and AP-1 activation in lymphomonocytes from Imatinib-treated patients, compared to samples from untreated patients. In parallel, IM treatment, in vivo and in vitro, were able to modulate the intracellular calcium concentration of peripheral blood mononuclear cells of CML patients by acting at the level of InsP(3) receptor in the endoplasmic reticulum and at the level of the purinergic receptors on plasma membrane. The results of this study show that measurements of NF-kB, AP-1, IL-6, IL-8, and intracellular calcium in CML patients treated with Imatinib may give important information to the hematologist on diagnostic criteria and are highly predictive in patients with newly diagnosed CML.

A peptide derived from herpes simplex virus type 1 glycoprotein H: membrane translocation and applications to the delivery of quantum dots.

Cell membranes are impermeable to most molecules that are not actively imported by living cells, including all macromolecules and even small molecules whose physiochemical properties prevent passive membrane diffusion. However, recently, we have seen the development of increasingly sophisticated methodology for intracellular drug delivery. Cell-penetrating peptides (CPPs), short peptides believed to enter cells by penetrating cell membranes, have attracted great interest in the hope of enhancing gene therapy, vaccine development and drug delivery. Nevertheless, to achieve an efficient intracellular delivery, further strategies to bypass the endocytotic pathway must be investigated. We report on a novel peptide molecule derived from glycoprotein gH of herpes simplex type I virus that is able to traverse the membrane bilayer and to transport a cargo into the cytoplasm with novel properties in comparison with existing CPPs. We use as cargo molecule quantum dots that do not significantly traverse the membrane bilayer on their own. FROM THE CLINICAL EDITOR: Cell-penetrating peptides have recently attracted great interest in optimizing gene therapy, vaccine development and drug delivery. In this study, a peptide derived from glycoprotein gH of herpes simplex I is investigated from this standpoint.

Quantitative and qualitative effect of gH625 on the nanoliposome-mediated delivery of mitoxantrone anticancer drug to HeLa cells.

The present work investigates in vitro the delivery of the anticancer drug mitoxantrone (MTX) to HeLa cancer cells by means of polyethylene glycol (PEG) liposomes functionalized with the novel cell penetrating peptide gH625. This hydrophobic peptide enhances the delivery of doxorubicin (Doxo) to the cytoplasm of cancer cells, while the mechanism of this enhancement has not yet been understood. Here, in order to get a better insight into the role of gH625 on the mechanism of liposome-mediated drug delivery, we treated HeLa cells with liposomes functionalized with gH625 and loaded with MTX; functionalized and not liposome were characterized in terms of their physico-chemical properties and drug release kinetics. To quantify the MTX uptake and to study the subcellular drug distribution and interaction, we took advantage of the intrinsic fluorescence of MTX and of the fluorescence-based techniques like fluorescence-activated cell sorting (FACS) and confocal spectral imaging (CSI). FACS data confirmed that gH625 increases the total intracellular MTX content. CSI data indicated that when liposomes are decorated with gH625 an enhanced staining of the internalized drug is observed mainly in hydrophobic regions of the cytoplasm, where the increased presence of an oxidative metabolite of the drug is observed. The cytotoxicity on HeLa cell line was higher for functionalized liposomes within 4-6h of treatment. To summarise, the MTX delivery with gH625-decorated nanoliposomes enhances the quantity of both the intracellular drug and of its oxidative metabolite and contributes to higher anticancer efficacy of the drug at the delay of 4-6h.