Local Lung Targeting of Tumor Associated Macrophages Combined with Cytoreductive Therapy Decrease Tumor Burden in a Secondary Lung Cancer Model

Backgrounds. The efficacy of a locally administered small molecule colony stimulating factor 1 receptor inhibitor (CSF-1Ri), PLX3397, alone or in combination with cytoreductive therapy (paclitaxel) in reducing the tumor burden of an in vivo model of secondary lung cancer was investigated in this work. Local administration of immunotherapy to the lungs may enhance lung biodistribution of such therapies and reduce potential unwanted off-target toxicity. In addition, combination of such therapy with low dose standard of care chemotherapy may offer improved anti-tumor effects. Methods. Murine breast cancer cells (4T1, known to be highly metastasized to the lungs) were transduced to express the genes luciferase and tdTomato, and cells were injected to female Balb/c mice before being treated with PLX (intratracheally administered), paclitaxel (intravenously given), or the combination therapy. Both ex vivo bioluminescent imaging and lung weights were used to evaluate tumor burden. Western blot was performed using lung tumors to assess the effect of PLX3397 on its molecular target (phosphorylated CSF-1R). Immunofluorescence and Flowcytometry were utilized to examine the impact of treatment on tumorigenic tumor associated macrophages (M2 TAM). Results. Single-agent treatment partially decreased tumor burden, while combination therapy led to a significant reduction in tumor burden. PLX3397 significantly inhibited the expression of phosphorylated CSF-1R and reduced the number of M2 TAM without affecting the total macrophage population, thereby increasing the anti-tumorigenic (M1)/M2 ratio. Conclusion. Tumor burden reduction upon local administration of PLX3397 to the lungs correlates with the marked inhibition of the molecular target and the decrease in M2 TAM.https://scholarscompass.vcu.edu/gradposters/1065/thumbnail.jp

LOCAL DELIVERY OF TUMOR ASSOCIATED MACROPHAGE IMMUNOTHERAPY FOR THE TREATMENT OF METASTASES TO THE LUNGS

Metastases are the leading cause of cancer-related deaths, and the lungs are one of the primary sites of metastases from several malignancies. Existing therapies fail to entirely eradicate tumors that disseminate and reside in lungs; therefore, patient prognosis significantly worsens. Conventional therapies utilized to treat lung tumors such as chemotherapy are administered systemically and typically exhibit poor lung biodistribution profiles, leading to many undesirable off target effects and suboptimal drug concentration in the tumor, which may promote resistance, further compromising the quality of life of secondary lung cancer patients. Immune cells that infiltrate the tumor microenvironment (TME) play a central role in cancer development, prognosis, and response to therapy, with tumor associated macrophages (TAMs) being one of the most abundant immunosuppressive cells in the TME of many malignancies. Several therapeutic strategies that target TAMs have been proposed. However, such therapeutics are given systemically and present similar challenges as standard of care chemotherapy and other treatments. In this work, we investigate the potential of an alternative strategy to treat lung metastases, in which we target TAMs by local lung administration of colony stimulating factor 1 receptor inhibitors (CSF-1Ris). We report the effects of locally administered CSF-1Ris in i) shifting the balance of TAMs away from the tumorigenic (M2-like) phenotype, ii) modulating the T cell profile and thus repurposing the immune response, and iii) as monotherapy or in combination with chemotherapy, in reducing lung tumor burden

Formulation of multicomponent inclusion complex of cyclodextrin-amino acid with Chrysin: Physicochemical characterization, cell viability and apoptosis assessment in human primary glioblastoma cell line

Chrysin (CR) is a water-insoluble drug reported for different therapeutic effects. The microwave irradiation method was used in this study to create a multicomponent inclusion complex (CR-MC) containing CR (drug) and carrier hydroxyl propyl beta cyclodextrin (HP β CD) and L-arginine (LA). The prepared inclusion complex (CR-MC) was evaluated for dissolution study and results were compared with chrysin physical mixture (CR-PM). Further, the samples were assessed for infra-red (IR), nuclear magnetic resonance (NMR), differential scanning calorimeter (DSC), scanning electron microscope (SEM) and molecular docking. Finally, the cell viability, reactive oxygen species and flow cytometer studies were also assessed to check the potential of the prepared inclusion complex on the human primary glioblastoma cell line (U87-MG cell). The phase solubility findings revealed a stability constant (773 mol L−1) as well as a complexation efficiency of 0.027. The dissolution study displayed a significant increase in CR release from CR-MC (99.03 ± 0.39%) > CR-PM (70.58 ± 1.16%) > pure CR (35.29 ± 1.55%). NMR and IR spectral data revealed no interaction between CR and carriers. SEM and DSC study results revealed the conversion into amorphous form. The molecular docking results illustrated a high docking score, which supports the findings of complex formation. The cell viability, reactive oxygen species, and flow cytometry studies results showed enhanced activity from CR-MC against the tested human primary glioblastoma cell line. From the results it has been observed that chrysin solubility significantly increased after complexation and there in vitro activity also enhanced against cancer cell line

Perspectives of Positively Charged Nanocrystals of Tedizolid Phosphate as a Topical Ocular Application in Rabbits

The aim of this study was the successful utilization of the positively charged nanocrystals (NCs) of Tedizolid Phosphate (TZP) (0.1% w/v) for topical ocular applications. TZP belongs to the 1, 3-oxazolidine-2-one class of antibiotics and has therapeutic potential for the treatment of many drug-resistant bacterial infections, including eye infections caused by MRSA, penicillin-resistant Streptococcus pneumonia and vancomycin-resistant Enterococcus faecium. However, its therapeutic usage is restricted due to its poor aqueous solubility and limited ocular availability. It is a prodrug and gets converted to Tedizolid (TDZ) by phosphatases in vivo. The sterilized NC1 was subjected to antimicrobial testing on Gram-positive bacteria. Ocular irritation and pharmacokinetics were performed in rabbits. Around a 1.29 to 1.53-fold increase in antibacterial activity was noted for NC1 against the B. subtilis, S. pneumonia, S. aureus and MRSA (SA-6538) as compared to the TZP-pure. The NC1-AqS was “practically non-irritating” to rabbit eyes. There was around a 1.67- and 1.43 fold increase in t1/2 (h) and Cmax (ngmL−1) while there were 1.96-, 1.91-, 2.69- and 1.41-times increases in AUC0–24h,AUC0–∞,AUMC0–∞ and MRT0–∞, respectively, which were found by NC1 as compared to TZP-AqS in the ocular pharmacokinetic study. The clearance of TDZ was faster (11.43 mLh−1) from TZP-AqS as compared to NC1 (5.88 mLh−1). Relatively, an extended half-life (t1/2; 4.45 h) of TDZ and the prolonged ocular retention (MRT0–∞; 7.13 h) of NC1 was found, while a shorter half-life (t1/2; 2.66 h) of TDZ and MRT0–∞(t1/2; 5.05 h)was noted for TZP-AqS, respectively. Cationic TZP-NC1 could offer increased transcorneal permeation, which could mimic the improved ocular bioavailability of the drug in vivo. Conclusively, NC1 of TZP was identified as a promising substitute for the ocular delivery of TZP, with better performance as compared to its conventional AqS

Topical Application of Linezolid–Loaded Chitosan Nanoparticles for the Treatment of Eye Infections

Linezolid (LZ) loaded chitosan–nanoparticles (CSNPs) was developed by the ionic–gelation method using Tripolyphosphate–sodium as a crosslinker for topical application for the treatment of bacterial eye infections. Particles were characterized by Zeta–Sizer (Malvern Nano–series). TEM was used for structural morphology. Encapsulation and drug loading were estimated by measuring the unencapsulated drug. In-vitro drug release in STF (pH 7) was performed through a dialysis membrane. Storage stability of LZ–CSNPs was checked at 25 °C and 40 °C for six months. The antimicrobial potency of NPs was evaluated on different Gram–positive strains. Ocular irritation and pharmacokinetic studies were completed in rabbits. Ex-vivo transcorneal permeation of the drug was determined through the rabbit cornea. Ionic interaction among the oppositely charged functional groups of CS and TPP generated the CSNPs. The weight ratio at 3:1, wt/wt (CS/TPP) with 21.7 mg of LZ produced optimal NPs (213.7 nm with 0.387 of PDI and +23.1 mV of ZP) with 71% and 11.2% encapsulation and drug loading, respectively. Around 76.7% of LZ was released from LZ–AqS within 1 h, while 79.8% of LZ was released from CSNPs at 12 h and 90% at 24 h. The sustained drug release property of CSNPS was evaluated by applying kinetic models. The linearity in the release profile suggested that the release of LZ from CSNPs followed the Higuchi–Matrix model. LZ–CSNPs have shown 1.4 to 1.6-times improved antibacterial activity against the used bacterial strains. The LZ–CSNPs were “minimally–irritating” to rabbit eyes and exhibited 4.4-times increased transcorneal permeation of LZ than from LZ–AqS. Around 3-, 1.2- and 3.1-times improved Tmax, Cmax, and AUC0–24 h, respectively were found for LZ–CSNPs during the ocular pharmacokinetic study. AqS has shown 3.1-times faster clearance of LZ. Conclusively, LZ–CSNPs could offer a better alternative for the prolonged delivery of LZ for the treatment of bacterial infections in the eyes

Development and Validation of UPLC–MS/MS Method for Quantitative Analysis of 5-Fluorouracil in Aqueous Humor of Rabbits

5-Fluorouracil (5-FU) is now used in eye drops for the management of conjunctival malignant melanoma, intraepithelial neoplasia, and corneal and conjunctival squamous cell carcinoma. The previously used methods for 5-FU quantification in AqH were time-consuming and less sensitive. Herein, a highly perceptive bioanalytical UPLC–MS/MS method was developed for the quantitative determination of 5-FU in the aqueous humor (AqH) of rabbits using allopurinol as the internal standard (IS). The 5-FU and IS were well separated in an Acquity™ HILIC column. Acetonitrile and 10 mM of ammonium acetate at 95:5 (v/v) were isocratically pumped at a 0.3 mL/min flow rate with a total runtime of 2.5 min. AqH samples were processed with a liquid–liquid extraction method in ethyl acetate. The 5-FU and IS were identified in the negative mode with electrospray ionization. The parent to daughter ion transitions for the 5-FU and IS occurred at m/z 128.92→41.68 and 134.80→64.10, respectively, as quantified using the multiple reaction monitoring mode. The developed method was validated with the ICH-Harmonized Guideline for Bioanalytical Method Validation, and the parameters were within acceptable limits. The calibration curve was linear at the 10.5–2000 ng/mL concentration range, with a correlation coefficient (R2) of 0.9946, and the lower limit of detection was 3.55 ng/mL. The developed and validated method was rapid, sensitive, accurate and robustly able to quantify 5-FU in rabbit AqH. The method was effectively applied to establish the ocular pharmacokinetics of 5-FU following the topical instillation of 5-FU-containing preparations in rabbits

Eflornithine Hydrochloride-Loaded Electrospun Nanofibers as a Potential Face Mask for Hirsutism Application

Hirsutism is a distressing condition that can affect women’s self-esteem due to the excessive amount of hair growth in different body parts, including the face. A temporary managing option is to develop a self-care routine to remove unwanted hair through shaving or waxing. Laser or electrolysis are alternative methods, but in some cases, the use of medications, such as the topical cream Vaniqa®, can help in reducing the growth of unwanted hair. Electrospun fibers have been used in several drug delivery applications, including skin care products, owing to their biocompatibility, biodegradability, high surface area-to-volume ratio, and dry nature that can release the encapsulated drugs with maximum skin penetration. Therefore, polyvinyl pyrrolidone (PVP) fibers were fabricated in combination with hyaluronic acid to deliver the active compound of Vaniqa®, i.e., Eflornithine hydrochloride (EFH), as a face mask to inhibit excess facial hair growth. The prepared drug-loaded fibers showed a diameter of 490 ± 140 nm, with an encapsulation efficiency of 88 ± 7% and a drug loading capacity of 92 ± 7 μg/mg. The in vitro drug release of EFH-loaded fibers exhibited an initial burst release of 80% in the first 5 min, followed by a complete release after 360 min, owing to the rapid disintegration of the fibrous mat (2 s). The in vitro cytotoxicity indicated a high safety profile of EFH at all tested concentrations (500–15.625 μg/mL) after 24-h exposure to human dermal fibroblast (HFF-1) cells. Therefore, this drug-loaded nanofibrous system can be considered a potentially medicated face mask for the management of hirsutism, along with the moisturizing effect that it possesses. Topical applications of the developed system showed reduced hair growth in mice to a certain extent