Formulation of Topical Flurbiprofen Solid Lipid Nanoparticle Gel Formulation Using Hot Melt Extrusion Technique.

Hot melt extrusion (HME) has been used for the formulation of topical solid lipid nanoparticle (SLN) gel without using any other size reduction technique including high pressure homogenization or sonication. SLN formulation solely using HME has not been applied to other drugs except IBU. Therefore, the purpose of the present study was to formulate FLB SLN solely using HME technique and evaluate the SLN formulation in inflammation animal model. Stable 0.5% w/v FLB SLN gel with particle size < 250 nm, PI < 0.3 and EE of > 98% was prepared. Differential scanning calorimetry (DSC) thermogram showed that the drug was converted to amorphous form in the HME process. Additionally, rheological studies demonstrated that FLB SLN gel and marketed FLB gel showed shear thinning property. FLB SLN formulation showed significantly (p < 0.05) higher peak force required to spread the formulation as compared to marketed FLB formulation. Stability studies showed that FLB SLN gel was stable for a month at room temperature and 2-4°C. Moreover, in vitro permeation test (IVPT) and ex vivo skin deposition study results revealed that FLB SLN gel showed significant (p < 0.05) increase in drug deposition in dermal layer and drug permeation as compared to control marketed formulation. Further, in vivo anti-inflammatory study showed equivalent inhibition of rat paw edema using 0.5% w/v FLB SLN gel which has 10 times less strength compared to control formulation. Overall, FLB SLN formulation was successfully manufactured solely using HME technique which resulted in enhanced the skin permeation of FLB and superior anti-inflammatory activity.

Targeting lung cancer stem cells using combination of Tel and Docetaxel liposomes in 3D cultures and tumor xenografts.

Cancer stem cells (CSCs) accounts for recurrence and resistance to chemotherapy in various tumors. Efficacy of chemotherapeutic drugs is limited by tumor stromal barriers, which hinder their penetration into deep tumor sites. We have earlier shown telmisartan (Tel) pretreatment prior to Docetaxel (DTX) administration enhances anti-cancer effects in non-small cell lung cancer (NSCLC). Herein, we demonstrated for the first time the efficacy of Docetaxel liposomes (DTXPL) in combination with Tel in 3D cultures of H460 cells by using polysaccharide-based hydrogels (TheWell Biosciences) and also in xenograft model of DTX resistant H460 derived CD133+ lung tumors. DTXPL and Tel combination showed enhanced cytotoxicity in H460 WT 3D cultures by two folds. In H460 3D cultures, Tel pretreatment showed increased liposomal uptake. DTXPL and Tel combination treated tumors showed reduction in tumor volume (p < .001), increased apoptosis and downregulation of CSC markers (p < .01) in H460 WT and DTX resistant CD133+ xenograft models.

Erlotinib-Valproic Acid Liquisolid Formulation: Evaluating Oral Bioavailability and Cytotoxicity in Erlotinib-Resistant Non-small Cell Lung Cancer Cells.

Lung cancer patients develop acquired resistance to tyrosine kinase inhibitors including erlotinib (ERL) after few months of primary treatment. Evidently, new chemotherapy strategies to delay or overcome the resistance are urgently needed to improve the clinical outcome in non-small cell lung cancer (NSCLC) patients. In this paper, we have investigated the cytotoxic interaction of ERL and valproic acid (VA) in ERL-resistant NSCLC cells and developed a liquisolid formulation of ERL-VA for improving oral bioavailability of ERL. ERL is weakly basic, biopharmaceutical classification system (BCS) class II drug with extremely poor aqueous solubility while VA is a branched chain fatty acid. Ionic interaction between ERL and VA (1:2 M ratio) resulted in significant enhancement in saturation solubility of ERL at different pH range. Liquisolid formulation of ERL-VA (EVLF) developed using PEG 400 and mesoporous calcium silicate was characterized for solid state and in vitro dissolution in biorelevant dissolution medium (FaSSIF and FeSSIF). Cytotoxicity of ERL was enhanced by 2-5 folds on co-incubation with VA in HCC827/ERL cell line. Flow cytometry analysis using AnnexinV-FITC assay demonstrated that VA and ERL alone have poor apoptotic effect on HCC827/ERL cells while combination showed around 69% apoptotic cells. Western blot analysis confirmed the role of survivin in overcoming resistance. In vivo pharmacokinetic studies of EVLF in rats demonstrated a 199% relative bioavailability compared to ERL suspension. Thus, EVLF could be a promising alternative to current ERL formulations in the treatment of NSCLC.

Combination of UVB Absorbing Titanium Dioxide and Quercetin Nanogel for Skin Cancer Chemoprevention.

Sunscreens are widely prescribed and used to prevent skin cancer; however, they have been reported to contain various chemicals which mimic hormones and disrupt hormonal functioning in humans. The aim of this study was to develop topical nanogel for skin cancer prevention using an antioxidant compound quercetin (Qu) and inorganic titanium dioxide (TiO2). Two formulations of Qu nanocrystals were optimized with low and high concentration of drug using the Box-Behnken design with the quadratic response surface model and further homogenized with TiO2. Qu nanocrystal (0.08% and 0.12%) formulations showed a particle size of 249.65 ± 2.84 nm and 352.48 ± 3.56 nm with zeta potential of - 14.7 ± 0.41 mV and - 19.6 ± 0.37 mV and drug content of 89.27 ± 1.39% and 90.38 ± 1.81% respectively. Scanning electron microscopy (SEM) images showed rod-shaped nanocrystals with a particle size below 400 nm. Qu (0.08%), Qu (0.12%), Qu (0.12%) + TiO2 (5%), and Qu (0.12%) + TiO2 (15%) nanogels showed over 70% drug release with significantly (p < 0.001) enhanced skin deposition of Qu as compare with Qu suspension within 24 h. The average numbers of tumor, tumor volume, and percentage of animals with tumors at onset in the Qu (0.12%) + TiO2 (15%) nanogel-pretreated group was found to be significantly (p < 0.05) less as compared with the UV only exposed group. Further, Qu (0.12%) + TiO2 (15%) nanogel significantly (p < 0.001) downregulated COX-2, EP3, EP4, PCNA, and cyclin D1 expressions in contrast to Qu and TiO2 only pretreated groups. Therefore, novel combination of Qu (0.12%) + TiO2 (15%) with enhanced skin deposition can be used as a chemopreventive strategy in UVB-induced skin photocarcinogenesis.

Tacrolimus Loaded PEG-Cholecalciferol Based Micelles for Treatment of Ocular Inflammation.

PURPOSE: Poor corneal permeability, nasolacrimal drainage and requirement of chronic administration are major drawbacks of existing therapies for ocular inflammation. Hence, we designed topical micelles of PEG2000 conjugated with cholecalciferol (PEGCCF). METHODS: Integrin targeted tacrolimus loaded PEGCCF micelles (TTM) were prepared by solvent diffusion evaporation method and characterized for particle size, osmolality, encapsulation efficiency and drug loading. Therapeutic potential of TTM was evaluated in benzalkonium chloride induced ocular inflammation model in BALB/c mice. Corneal flourescein staining and histopathological analysis of corneal sections was performed. RESULTS: TTM had a particle size of 45.3 ± 5.3 nm, encapsulation efficiency (88.7 ± 0.9%w/w) and osmolality of 292-296 mOsmol/Kg. TTM significantly reduced the corneal fluorescence as compared to tacrolimus suspension (TACS). H&E staining showed that TTM could restore corneal epithelial thickness, reduce stromal edema (p < 0.05) and decrease number of inflammatory cells (p < 0.01) compared with TACS. Immunohistochemistry analysis demonstrated lower expression of Ki67 + ve cells (p < 0.05) and IL-6 throughout the cornea against TACS (p < 0.01) and the control (p < 0.001). CONCLUSIONS: TTM is an innovative delivery system for improving ocular inflammation due to a) integrin targeting b) PEGCCF in the form of carrier and c) anti-inflammatory and synergistic effect (due to Pgp inhibition) with TAC.

Cholecalciferol-PEG Conjugate Based Nanomicelles of Doxorubicin for Treatment of Triple-Negative Breast Cancer.

Triple-negative breast cancer (TNBC) is the leading cancer in women. Chemotherapeutic agents used for TNBC are mainly associated with dose-dependent toxicities and development of resistance. Hence, novel strategies to overcome resistance and to offer dose reduction are warranted. In this study, we designed a novel dual-functioning agent, conjugate of cholecalciferol with PEG2000 (PEGCCF) which can self-assemble into micelles to encapsulate doxorubicin (DOX) and act as a chemosensitizer to improve the therapeutic potential of DOX. DOX-loaded PEGCCF (PEGCCF-DOX) micelles have particle size, polydispersity index (PDI), and zeta potential of 40 ± 8.7 nm, 0.180 ± 0.051, and 2.39 ± 0.157 mV, respectively. Cellular accumulation studies confirmed that PEGCCF was able to concentration-dependently enhance the cellular accumulation of DOX and rhodamine 123 in MDA-MB-231 cells through its P-glycoprotein (P-gp) inhibition activity. PEGCCF-DOX exhibited 1.8-, 1.5-, and 2.9-fold enhancement in cytotoxicity of DOX in MDA-MB-231, MDA-MB-468, and MDA-MB-231DR (DOX-resistant) cell lines, respectively. Western blot analyses showed that PEGCCF-DOX caused significant reduction in tumor markers including mTOR, c-Myc, and antiapoptotic marker Bcl-xl along with upregulation of preapoptotic marker Bax. Further, reduction in mTOR activity by PEGCCF-DOX indicates reduced P-gp activity due to P-gp downregulation as well and, hence, PEGCCF causes enhanced chemosensitization and induces apoptosis. Substantially enhanced apoptotic activity of DOX (10-fold) in MDA-MB-231(DR) cells confirmed apoptotic potential of PEGCCF. Conclusively, PEGCCF nanomicelles are promising delivery systems for improving anticancer activity of DOX in TNBC, thereby reducing its side effects and may act as a potential carrier for other chemotherapeutic agents.