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Phototherapy (PT), a light activated treatment modality, is a potential therapeutic option for the treatment of melanoma. In spite of the excellent safety profile and absorption in the near infrared (NIR) range, clinical potential of indocyanine green (ICG) as PT is limited by its short half-life and inefficient tumor accumulation. In this study, we have covalently conjugated ICG-NH 2 to the pendant carboxyl groups of poly (ethylene glycol)-block-poly(2-methyl-2-carboxyl-propylene carbonate) (PEG-PCC) copolymer using carbodiimide coupling, which self-assembled into micelles with a particle size of 30–50 nm and high ICG loading. These ICG conjugated micelles exhibited significant in vitro photodynamic cytotoxicity. Use of sodium azide and NIR radiation at 4 °C revealed photodynamic and photothermal as mechanism of cytotoxicity of ICG solution and ICG conjugated micelles, respectively. In vivo NIR imaging demonstrated that ICG conjugated micelles prolonged its circulation and increased tumor accumulation through enhanced permeability and retention (EPR) effect. Enhanced tumor accumulation improved therapeutic efficacy with complete tumor regression in NIR irradiated ICG conjugated micelles compared to ICG solution and control in a A375 human melanoma tumor model in athymic nude mice. These results suggest that ICG conjugated micelles can be potentially utilized for PT and imaging of melanoma. [ABSTRACT FROM AUTHOR]

Purpose: Hedgehog (Hh) and peroxisome proliferator-activated receptor gamma (PPAR-γ) are major signaling pathways involved in the pathogenesis of liver fibrosis. Since Hh inhibitor, vismodegib (GDC) and PPAR-γ agonist, rosiglitazone (RSG) have poor water solubility, our objective was to formulate biodegradable polymeric nanoparticles encapsulating GDC and RSG for treating liver fibrosis. Methods: Methoxy-polyethylene-glycol-b-poly(carbonate-co-lactide) [mPEG-b-p(CB-co-LA)] was synthesized and characterized using H NMR. Nanoparticles were prepared using this polymer by emulsification/solvent evaporation method to encapsulate GDC and RSG either alone or in combination. Nanoparticles were characterized for particle size, drug loading, drug release, and anti-fibrotic efficacy after tail vein injection into common bile duct ligated (CBDL) fibrotic rats. Results: mPEG-b-p(CB-co-LA) copolymer has molecular weight of 30,000 Da as determined by H NMR. Nanoparticles were monodisperse with a mean particle size of 120-130 nm. Drug loading was 5% and 2% w/w for GDC and RSG, respectively. Nanoparticles carrying both GDC and RSG were formulated at half of their individual drug loading. Systemic administration of drug loaded nanoparticles protected liver injury in CBDL rats by suppressing the activation of hepatic stellate cells, and decreasing inflammatory cytokines. Conclusion: Polymeric nanoparticles for co-delivery of Hh inhibitor and PPAR-γ agonist have the potential to treat liver fibrosis by intervening complex fibrotic cascade. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the potential of human bone marrow derived mesenchymal stem cells (hBMSCs) as gene carriers for improving the outcome of human islet transplantation. hBMSCs were characterized for the expression of phenotypic markers and transduced with Adv-hVEGF-hIL-1Ra to overexpress human vascular endothelial growth factor (hVEGF) and human interleukin-1 receptor antagonist (hIL-1Ra). Human islets were co-cultured with hBMSCs overexpressing hVEGF and hIL-1Ra. Islet viability was determined by membrane fluorescent method and glucose stimulation test. Transduced hBMSCs and human islets were co-transplanted under the kidney capsule of NOD.Cg-Prkdcscid Il2rgtm1Wjl/SzJ (NSG) diabetic mice and blood glucose levels were measured over time to demonstrate the efficacy of genetically modified hBMSCs. At the end of study, immunofluorescent staining of kidney section bearing islets was performed for insulin and von Willebrand Factor (vWF). hBMSCs were positive for the expression of CD73, CD90, CD105, CD146 and Stro-1 surface markers as determined by flow cytometry. Transduction of hBMSCs with adenovirus did not affect their stemness and differentiation potential as confirmed by mRNA levels of stem cell markers and adipogenic differentiation of transduced hBMSCs. hBMSCs were efficiently transduced with Adv-hVEGF-hIL-1Ra to overexpress hVEGF and hIL-1Ra. Live dead cell staining and glucose stimulation test have shown that transduced hBMSCs improved the viability of islets against cytokine cocktail. Co-transplantation of human islets with genetically modified hBMSCs improved the glycemic control of diabetic NSG mice as determined by mean blood glucose levels and intraperitoneal glucose tolerance test. Immunofluorescent staining of kidney sections was positive for human insulin and vWF. In conclusion, our results have demonstrated that hBMSCs may be used as gene carriers and nursing cells to improve the outcome of islet transplantation. [ABSTRACT FROM AUTHOR]

Purpose: Since our newly synthesized potent 5-indolyl derivative, (2-(1 H-Indol-5-yl) thiazol-4-yl) 3, 4, 5-trimethoxyphenyl methanone (LY293), to treat resistant melanoma was hydrophobic, our objective was to synthesize a biodegradable copolymer for formulating this drug into nanoparticles and to determine its anticancer activity and mechanism of action. Methods: Methoxy poly (ethylene glycol)-b-poly (carbonate-co-lactide) [mPEG-b-P (CB-co-LA)] was synthesized for formulating LY293 into nanoparticles by o/w emulsification and stabilization by solvent evaporation. Particle size, drug release profile, in vitro efficacy in multiple melanoma cells, and mechanism of action of drug-loaded nanoparticles were determined. Results: LY293-loaded nanoparticles with 170 nm mean size and 2.2 and 4.16% drug loading efficiently inhibited proliferation of A375 and B16F10 cells with IC of 12.5 nM and 25 nM, respectively. LY293 circumvented multidrug resistance and inhibited proliferation of Pgp overexpressing MDA-MB435/LCC6 MDR1 melanoma cells. Upon treatment with LY293-loaded nanoparticles, A375 cells underwent cell cycle arrest in G2/M phase and apoptotic cell death. Immunofluorescence images showed inhibition of tubulin polymerization after treatment with LY293. Conclusion: LY293-loaded mPEG-b-P (CB-co-LA) nanoparticles showed excellent efficacy and induced apoptosis in melanoma cells. These polyester/polycarbonate-based nanoparticles provided an excellent platform to deliver different poorly soluble drugs to melanoma. [ABSTRACT FROM AUTHOR]

BTK inhibitor exposure increases significantly when coadministered with CYP3A inhibitors, which may lead to dose-related toxicities. This study explored the pharmacokinetics, efficacy, and safety of zanubrutinib when coadministered with moderate or strong CYP3A inhibitors in 26 patients with relapsed or refractory B-cell malignancies. Coadministration of zanubrutinib (80 mg BID) with moderate CYP3A inhibitors fluconazole and diltiazem or zanubrutinib (80 mg QD) with strong CYP3A inhibitor voriconazole resulted in comparable exposures to zanubrutinib (320 mg QD) with AUC0-24h geometric least squares mean ratios approaching 1 (0.94, 0.81, and 0.83, for fluconazole, diltiazem, and voriconazole, respectively). The most common treatment-emergent adverse events were contusion (26.9%), back pain (19.2%), constipation and neutropenia (15.4% each), and rash, diarrhea, and fall (11.5% each). This study supports current United States Prescribing Information dose recommendations for the coadministration of reduced-dose zanubrutinib with moderate or strong CYP3A inhibitors and confirms the favorable efficacy and safety profile of zanubrutinib. [ABSTRACT FROM AUTHOR]

Hedgehog (Hh) signaling is involved in the pathogenesis of liver fibrosis. It has been previously shown that Hh-inhibitor cyclopamine (CYA) can reduce liver fibrosis in rats. However, CYA is not stable in vivo, which limits its clinical application. This study compares the antifibrotic potential of two known Hh antagonists, vismodegib (GDC-0449, abbreviated to GDC) and CYA. GDC is a synthetic molecule presently in clinical cancer trials and has been reported to be safe and efficacious. These drugs attenuated early liver fibrosis in common bile duct ligated rats, improved liver function, and prevented hepatic stellate cell (HSC) activation, thereby suppressing epithelial to mesenchymal transition (EMT). While both CYA and GDC increased the number of proliferating cell nuclear antigen positive liver cells in vivo, only CYA increased Caspase-3 expression in HSCs in rat livers, suggesting that while GDC and CYA effectively attenuate early liver fibrosis, their hepatoprotective effects may be mediated through different modes of action. Thus, GDC has the potential to serve as a new therapeutic agent for treating early liver fibrosis. [ABSTRACT FROM AUTHOR]

Melanoma is the most aggressive type of skin cancer. It is highly metastatic, migrating through lymph nodes to distant sites of the body, especially to lungs, liver and brain. Systemic chemotherapy remains the mainstay of treatment; however, the development of multidrug resistance (MDR) restricts the efficacy of current chemotherapeutic drugs. We synthesized a series of microtubule destabilizers, substituted methoxybenzoyl-ary-thiazole (SMART) compounds, which inhibited tubulin polymerization and effectively circumvented MDR. Due to poor water solubility of SMART compounds, co-solvent delivery is required for their systemic administration, which is usually associated with hepatotoxicity, nephrotoxicity and hemolysis. To solve this problem and also to increase circulation time, we synthesized a new SMART analogue, SMART-OH, and its polymer-drug conjugate, methoxy-poly (ethylene glycol)- block -poly (2-methyl-2-carboxyl-propylene carbonate- graft -SMART- graft -dodecanol) (abbreviated as P-SMART), with 14.3 ± 2.8% drug payload of SMART-OH. Similar to its parent drug, P-SMART showed significant anticancer activity against melanoma cells in cytotoxicity, colony formation, and cell invasion studies. In addition, P-SMART treatment led to cell cycle arrest at G2/M phase and cell accumulation in sub-G1 phase. We established a model of metastatic melanoma to the lung in C57/BL6 albino mice to determine in vivo efficacy of P-SMART and SMART-OH at the dose of 20 mg/kg. P-SMART treatment resulted in significant inhibition of tumor growth and prolonged mouse median survival. In conclusion, P-SMART, a novel polymer-microtubule destabilizer conjugate, has the potential to treat metastatic melanoma. [ABSTRACT FROM AUTHOR]