Optimization of DOTAP/chol Cationic Lipid Nanoparticles for mRNA, pDNA, and Oligonucleotide Delivery.

Lipid nanoparticles (LNPs) can be used as delivery vehicles for nucleic acid biotherapeutics. In fact, LNPs are currently being used in the Pfizer/BioNTech and Moderna COVID-19 vaccines. Cationic LNPs composed of 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP)/cholesterol (chol) LNPs have been classified as one of the most efficient gene delivery systems and are being tested in numerous clinical trials. The objective of this study was to examine the effect of the molar ratio of DOTAP/chol, PEGylation, and lipid to mRNA ratio on mRNA transfection, and explore the applications of DOTAP/chol LNPs in pDNA and oligonucleotide transfection. Here we showed that PEGylation significantly decreased mRNA transfection efficiency of DOTAP/chol LNPs. Among non-PEGylated LNP formulations, 1:3 molar ratio of DOTAP/chol in DOTAP/chol LNPs showed the highest mRNA transfection efficiency. Furthermore, the optimal ratio of DOTAP/chol LNPs to mRNA was tested to be 62.5 µM lipid to 1 µg mRNA. More importantly, these mRNA-loaded nanoparticles were stable for 60 days at 4 °C storage without showing reduction in transfection efficacy. We further found that DOTAP/chol LNPs were able to transfect pDNA and oligonucleotides, demonstrating the ability of these LNPs to transport the cargo into the cell nucleus. The influence of various factors in the formulation of DOTAP/chol cationic LNPs is thus described and will help improve drug delivery of nucleic acid-based vaccines and therapies.

Brigatinib: Novel ALK Inhibitor for Non-Small-Cell Lung Cancer.

OBJECTIVE: We review here the pharmacology, pharmacokinetics, efficacy, safety, dosage and administration, potential drug-drug interactions and place in therapy of brigatinib for abnormal anaplastic lymphoma kinase (ALK) specific non-small-cell lung cancer (NSCLC). DATA SOURCES: A literature search using PubMed was conducted using the terms brigatinib and ALK positive NSCLC from January 2013 to November 2018. STUDY SELECTION AND DATA EXTRACTION: All English-language articles evaluating brigatinib were analyzed for this review. DATA SYNTHESIS: Brigatinib was granted approval for the treatment of patients with metastatic ALK+ NSCLC who have progressed on or are intolerant to crizotinib. It is administered at a dose of 90 mg orally once daily for the first 7 days then, if tolerated, increased to a dose of 180 mg orally once daily. Common adverse effects include nausea, fatigue, diarrhea, increased creatine phosphokinase levels, headache, dyspnea, and hypertension. Serious treatment-emergent adverse effects were pulmonary related. Relevance to Patient Care and Clinical Practice: This article discusses the clinical trials that led to the accelerated approval of brigatinib for its ability to overcome crizotinib-resistant mutations and for its increased central nervous system penetration properties. CONCLUSION: Brigatinib was granted accelerated approval for the treatment of patients with metastatic ALK+ NSCLC who have progressed on or are intolerant to crizotinib. In a subset of NSCLC patients, brigatinib increases survival for approximately 1 year; however, side effects were detected.

Phenethyl Isothiocyanate and Cisplatin Co-Encapsulated in a Liposomal Nanoparticle for Treatment of Non-Small Cell Lung Cancer.

Lung cancer is the leading cause of cancer-related death in the Unites States, and approximately 85% of all lung cancers are classified as non-small cell lung cancer (NSCLC), which is extremely difficult to treat and its survival rate is low. After decades of clinical trials, the most effective treatments are still those that implement the first-generation platinum anticancer agent cisplatin (CDDP) in combination with other drugs. We previously demonstrated that the naturally-occurring compound phenethyl isothiocyanate (PEITC) can be used to sensitize NSCLC cells to CDDP. Furthermore, co-encapsulation of PEITC and CDDP in liposomes enhances their toxicity toward NSCLC cells. We here optimize liposomal-PEITC-CDDP, demonstrate the release of PEITC and CDDP from the nanoparticle, and show that liposomal-PEITC-CDDP is much more toxic toward both A549 and H596 human NSCLC cell lines than toward WI-38 and BEAS-2B human normal lung cell lines. Thus, we have prepared an efficacious therapy that has significantly higher toxicity toward cancer cell lines than normal cell lines.

Chemoradiotherapeutic Magnetic Nanoparticles for Targeted Treatment of Nonsmall Cell Lung Cancer.

Lung cancer is the leading cause of cancer-related death in the United States and approximately 85% of all lung cancers are classified as nonsmall cell (NSCLC). We here use an innovative approach that may ultimately allow for the clinician to target tumors and aggressively reduce tumor burden in patients with NSCLC. In this study, a platinum (Pt)-based chemotherapeutic (cisplatin, carboplatin, or oxaliplatin) and holmium-165 (Ho), which can be neutron-activated to produce the holmium-166 radionuclide, have been incorporated together in a garnet magnetic nanoparticle (HoIG-Pt) for selective delivery to tumors using an external magnet. The synthesized magnetic HoIG nanoparticles were characterized using PXRD, TEM, ICP-MS, and neutron-activation. Platinum(II) drugs were incorporated onto HoIG, and these were characterized using FTIR, EDX, ICP-MS, and zeta potential measurements, and in vitro and in vivo studies were performed using a HoIG-platinum system. Results indicate that neutron-activated (166)HoIG-cisplatin is more toxic toward NSCLC A549 cells than is blank (166)HoIG and free cisplatin, and that when an external magnetic field is applied in vivo, higher tumor to liver ratios of Ho are observed than when no magnet is applied, suggesting that magnetic targeting is achieved using this system. Furthermore, an efficacy study demonstrated the inhibition of tumor growth by chemoradiotherapeutic magnetic nanoparticles, compared to no treatment controls.

Tetracycline-Containing MCM-41 Mesoporous Silica Nanoparticles for the Treatment of Escherichia coli.

Tetracycline (TC) is a well-known broad spectrum antibiotic, which is effective against many Gram positive and Gram negative bacteria. Controlled release nanoparticle formulations of TC have been reported, and could be beneficial for application in the treatment of periodontitis and dental bone infections. Furthermore, TC-controlled transcriptional regulation systems (Tet-on and Tet-off) are useful for controlling transgene expression in vitro and in vivo for biomedical research purposes; controlled TC release systems could be useful here, as well. Mesoporous silica nanomaterials (MSNs) are widely studied for drug delivery applications; Mobile crystalline material 41 (MCM-41), a type of MSN, has a mesoporous structure with pores forming channels in a hexagonal fashion. We prepared 41 ± 4 and 406 ± 55 nm MCM-41 mesoporous silica nanoparticles and loaded TC for controlled dug release; TC content in the TC-MCM-41 nanoparticles was 18.7% and 17.7% w/w, respectively. Release of TC from TC-MCM-41 nanoparticles was then measured in phosphate-buffered saline (PBS), pH 7.2, at 37 °C over a period of 5 h. Most antibiotic was released from both over this observation period; however, the majority of TC was released over the first hour. Efficacy of the TC-MCM-41 nanoparticles was then shown to be superior to free TC against Escherichia coli (E. coli) in culture over a 24 h period, while blank nanoparticles had no effect.

Enhanced toxicity of cisplatin with chemosensitizer phenethyl isothiocyanate toward non-small cell lung cancer cells when delivered in liposomal nanoparticles.

Naturally occurring phenethyl isothiocyanate (PEITC) was previously shown to sensitize human non-small cell lung cancer (NSCLC) cells to the platinum anticancer drug cisplatin (CDDP). Here, CDDP and PEITC were encapsulated in approximately 130 nm liposomes composed of 1,2-distearoyl-sn-glycero-3-phosphocholine (DSPC) and L-α-phosphatidylglycerol (EPG). The liposomal formulation enhanced the toxicity of this doublet (1:2 molar ratio of CDDP/PEITC) toward NCI-H596 NSCLC cells; the percent survival of cells was 30.2±6.2% after treatment with the nanoparticle formulation, compared to 50.9±3.5% when administered together free. Thus, such a treatment modality could prove useful in the clinic for the treatment of NSCLC.

Solid dispersions of the penta-ethyl ester prodrug of diethylenetriaminepentaacetic acid (DTPA): formulation design and optimization studies.

The penta-ethyl ester prodrug of diethylenetriaminepentaacetic acid (DTPA), which exists as an oily liquid, was incorporated into a solid dispersion for oral administration by the solvent evaporation method using blends of polyvinylpyrrolidone (PVP), Eudragit® RL PO and α-tocopherol. D-optimal mixture design was used to optimize the formulation. Formulations that had a high concentration of both Eudragit® RL PO and α-tocopherol exhibited low water absorption and enhanced stability of the DTPA prodrug. Physicochemical properties of the optimal formulation were evaluated using Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). In vitro release of the prodrug was evaluated using the USP Type II apparatus dissolution method. DSC studies indicated that the matrix had an amorphous structure, while FTIR spectrometry showed that DTPA penta-ethyl ester and excipients did not react with each other during formation of the solid dispersion. Dissolution testing showed that the optimized solid dispersion exhibited a prolonged release profile, which could potentially result in a sustained delivery of DTPA penta-ethyl to enhance bioavailability. In conclusion, DTPA penta-ethyl ester was successfully incorporated into a solid matrix with high drug loading and improved stability compared to prodrug alone.

Preparation of neutron-activatable holmium nanoparticles for the treatment of ovarian cancer metastases.

Nanoparticles containing stable holmium ((165) Ho) are prepared by nanotemplate engineering and subsequently irradiated in a neutron flux to yield (166) Ho, a beta-emitting radiotherapeutic isotope. After intraperitoneal injection to mice bearing SKOV-3 ovarian tumors, significant tumor accumulation of the (166) Ho-nanoparticles is observed by SPECT imaging indicating the potential of these neutron activatable nanoparticles for internal radiation therapy of ovarian cancer metastases.

Preparation and Optimization of an Ultraflexible Liposomal Gel for Lidocaine Transdermal Delivery.

The pain caused by lidocaine injections into the face prior to facial plastic surgeries intended to remove growths or tumorous lesions has been reported by many patients to be the worst part of these procedures. However, the lidocaine gels and creams currently on the market do not deliver an equal or better local anesthetic effect to replace these injections. To develop an alternative to the painful local anesthetic injection, we prepared ultraflexible liposomes using soy phosphatidylcholine, lidocaine, and different amounts of sodium cholate, a surfactant. The prepared ultraflexible liposomes (UFLs) were examined for particle size, zeta potential, cytotoxicity, and in vitro release. By using a carbomer as a gelling agent, the prepared UFL lidocaine gels were evaluated for their penetration ability in a Franz diffusion cell, using Strat-M membranes. The formulation achieving the highest amount of penetrated lidocaine was chosen for further pH, viscosity, and stability tests. The local anesthetic efficacy of the formulation was investigated by an in vivo tail-flick test in rats. Our findings suggested that this topical gel formulated with ultraflexible liposomal lidocaine has enhanced skin permeation ability, as well as an improved local analgesic effect from the lidocaine.

Laminated holmium-166-containing electrospun bandages for use against skin cancer.

The number of non-melanoma skin cancer (NMSC) cases in the US will increase significantly over the next decade due to a rise in UV exposure. One of the treatment methods used to remove NMSC lesions is radiation therapy. The two types of radiation therapy used in the clinic are external beam therapy and brachytherapy. However, both require specialized on-site instrumentation and for patients to remain immobile. In this work, we studied an alternative radiation therapy - one that does not require expensive on-site equipment and would allow for enhanced patient mobility and, thus, comfort. We prepared sealed source, nylon-laminated holmium-166-containing radiotherapeutic bandages and used them in C3H/HeN mice with murine SCCVII tumor grafts. Overall, tumor sizes were smallest when treated with therapeutically relevant radiation doses via radiotherapeutic bandages (compared to controls), and no histological evidence of toxicity to tissues was observed. Thus, our optimized radiotherapeutic bandage offers a flexible approach to treating NMSC.

Proteins as binding targets of isothiocyanates in cancer prevention.

Isothiocyanates are versatile cancer-preventive compounds. Evidence from animal studies indicates that the anticarcinogenic activities of ITCs involve all the major stages of tumor growth: initiation, promotion and progression. Epidemiological studies have also shown that dietary intake of ITCs is associated with reduced risk of certain human cancers. A number of mechanisms have been proposed for the chemopreventive activities of ITCs. To identify the molecular targets of ITCs is a first step to understand the molecular mechanisms of ITCs. Studies in recent years have shown that the covalent binding to certain protein targets by ITCs seems to play an important role in ITC-induced apoptosis and cell growth inhibition and other cellular effects. The knowledge gained from these studies may be used to guide future design and screen of better and more efficacious compounds. In this review, we intend to cover all potential protein targets of ITCs so far studied and summarize what are known about their binding sites and the potential biological consequences. In the end, we also offer discussions to shed light onto the relationship between protein binding and reactive oxygen species generation by ITCs.

A Method for Liposome Co-encapsulation of Phenethyl Isothiocyanate and Cisplatin and Determining Its Toxicity Against Lung and Lung Cancer Cells.

Non-small cell lung cancer (NSCLC) is one of the leading causes of cancer-related deaths in the United States. It is extremely difficult to treat, and its survival rate is low. Today, the most effective treatments are still those that implement the platinum anticancer drug cisplatin (CDDP) in combination with other drugs. We previously demonstrated that the naturally occurring compound phenethyl isothiocyanate (PEITC) could be used to sensitize NSCLC cells to CDDP. Furthermore, co-encapsulation of PEITC and CDDP in liposomes enhances their toxicity toward NSCLC cells. We have optimized a liposomal-PEITC-CDDP formulation and investigated its cytotoxicity. We determined that liposomal-PEITC-CDDP is much more toxic toward human NSCLC cell lines than it is toward human normal lung cell lines. In this chapter, we describe detailed methods for preparing liposomal-PEITC-CDDP and determining its cytotoxicity.

Physicochemical Factors That Influence the Biocompatibility of Cationic Liposomes and Their Ability to Deliver DNA to the Nuclei of Ovarian Cancer SK-OV-3 Cells.

Cationic liposomes composed of 3-[N-(N',N'-dimethylaminoethane)-carbamoyl] cholesterol (DC-chol) and dioleoylphosphatidylethanolamine (DOPE) have previously been shown to have applications in gene delivery. Our study aims to explore the effects of inclusion of polyethylene glycol (PEG) and using different molar ratios of DC-chol/DOPE on size, zeta potential, cytotoxicity and DNA delivery of DC-chol/DOPE liposomes. Our results show that PEGylation reduces the cytotoxicity of DC-chol/DOPE liposomes, and, furthermore, PEGylated liposome-DNA lipoplexes are smaller in size and more uniform in size distribution than those that are not PEGylated. Additionally, toxicity against ovarian cancer SKOV-3 cells decreases with the amount of cationic DC-chol present in the formulation; however, decreased delivery of DNA to cellular nuclei is also observed. Transfection with the PEGylated liposomes was successfully demonstrated using plasmid DNA with a known functional outcome. These results offer further insight into physicochemical properties important for cationic liposomes as vehicles for DNA delivery and demonstrate the potential of PEGylated DC-chol/DOPE liposomes as systemic delivery carriers for DNA-mediated ovarian cancer therapy.

Phenethyl Isothiocyanate-Containing Carbomer Gel for Use against Squamous Cell Carcinoma.

It is currently estimated that one in every five Americans will develop skin cancer during their lifetime. Squamous cell carcinoma (SCC) is a common type of skin cancer that can develop due to the skin's exposure to the sun. Herein, we prepared a topical gel containing 0.5% v/w phenethyl isothiocyanate (PEITC) for the treatment of SCC. PEITC is a naturally occurring isothiocyanate that has been shown to have efficacy against various types of cancer in preclinical studies. We first incorporated PEITC into a carbomer gel. A uniform formulation was prepared, and its viscosity was appropriate for topical application. We then demonstrated the release of PEITC from the gel into and through a Strat-M skin-like membrane. Finally, the effects of the PEITC-containing gel were tested against SCC and normal keratinocytes skin cells in culture, and these results were compared to those obtained for free 5-fluoruracil (5-FU), a commonly used skin-cancer drug. Our results show that a homogeneous PEITC-containing topical gel can be prepared and used to kill SCC cells. Thus, our formulation may be useful for treating SCC in the clinic.

Tirbanibulin: Topical Treatment for Actinic Keratosis.

We review here the pharmacology, pharmacokinetics, efficacy, dosage and administration, and place in therapy of tirbanibulin for the treatment of actinic keratosis (AK). A literature search using PubMed was conducted using the terms tirbanibulin (tirbanibulin) and actinic keratosis from September 2014 to February 2021. All English-language articles evaluating tirbanibulin were analyzed for this review. Tirbanibulin was granted approval for the treatment of AK of the face or scalp as a first-line therapy. It is administered at a dose of 2.5 mg in 250 mg of white or off-white ointment for a 25 cm2 contiguous treatment surface for 5 consecutive days. Adverse effects include flaking/scaling, crusting, swelling, vesiculation/pustulation, and erosion/ulceration. This article discusses the clinical trials that led to the approval of tirbanibulin and comparison with other approved topical ointments indicated for the treatment of AK. In the clinical trials, all participants experienced a decrease in lesion size or saw complete clearance with minimal adverse effects.

Sensitization of non-small cell lung cancer cells to cisplatin by naturally occurring isothiocyanates.

We show that naturally occurring isothiocyanates (ITCs) sensitize human non-small cell lung cancer cells to cisplatin. Moreover, the structure of the ITC side chain moiety is important for sensitization. In NCI-H596 cells, 20 microM benzyl isothiocyanate (BITC) and phenethyl isothiocyanate (PEITC) enhance the efficacy of various concentrations of cisplatin, but sulforaphane (SFN) does not. Reducing the concentration of BITC and PEITC to 10 microM still allows for the sensitization of cells to cisplatin. Neither cellular platinum accumulation nor DNA platination account for this increased cytotoxicity. BITC and PEITC deplete beta-tubulin, but SFN does not; this correlates with and may be important for sensitization.

Formation of carbonato and hydroxo complexes in the reaction of platinum anticancer drugs with carbonate.

The second-generation Pt(II) anticancer drug carboplatin is here shown to react with carbonate, which is present in blood, interstitial fluid, cytosol, and culture medium, to produce platinum-carbonato and -hydroxo complexes. Using [(1)H-(15)N] HSQC NMR and (15)N-labeled carboplatin, we observe that cis-[Pt(CBDCA-O)(OH)(NH(3))(2)](-), cis-[Pt(OH)(2)(NH(3))(2)], cis-[Pt(CO(3))(OH)(NH(3))(2)](-), and what may be cis-[Pt(CO(3))(NH(3))(2)] are produced when 1 is allowed to react in 23.8 mM carbonate buffer. When (15)N-labeled carboplatin is allowed to react in 0.5 M carbonate buffer, these platinum species, as well as other hydroxo and carbonato species, some of which may be dinuclear complexes, are produced. Furthermore, we show that the carbonato species cis-[Pt(CO(3))(OH)(NH(3))(2)](-) is also produced when cisplatin is allowed to react in carbonate buffer. The study outlines the conditions under which carboplatin and cisplatin form carbonato and aqua/hydroxo species in carbonate media.

Adsorption of the Pt(II) anticancer drug carboplatin by mesoporous silica.

MCM-41, a mesoporous silica nanomaterial with a high surface area for adsorption of small molecules, is a potential new type of delivery vehicle for therapeutic and diagnostic agents. In this report, we show that MCM-41 adsorbs the front-line anticancer drug carboplatin, [Pt(CBDCA-O,O')(NH3)2] (CBDCA=cyclobutane-1,1-dicarboxylate; 1), which is used to treat ovarian, lung, and other types of cancer. UV/Visible difference absorption spectroscopy shows that MCM-41 adsorbs 1.8+/-0.2% of its own weight of carboplatin after a 24 h exposure to 26.9 mM drug in H2O. The pseudo-first-order rate constant for adsorption of carboplatin by MCM-41, measured using [1H,15N] heteronuclear single quantum coherence (HSQC) NMR, and 15N-labeled carboplatin is k(1)=2.92+/-2.17 x 10(-6) s(-1) at ca. 25 degrees.

Influence of carbonate on the binding of carboplatin to DNA.

The reaction of aged carboplatin (reaction of carboplatin in 24 mM NaHCO(3) for 45 h, 37 degrees, pH 8.6) with pBR322 DNA at 0 < r < 2.8, where r = [drug]/[DNA-bp], in 24 mM HEPES buffer, pH 7.4, for 24 h, followed by agarose gel electrophoresis showed DNA mobility changes consistent with unwinding closed circular DNA. However, identical experiments conducted in a two-buffer system, 24 mM HEPES plus 24 mM carbonate, showed no DNA mobility changes, indicating that carbonate blocks formation of the 1,2 intrastrand cross-link on DNA. Studies with aged carboplatin and with cisplatin carried out with ca. 4.0 < r < 10.0 in the two-buffer system show that some DNA binding and unwinding occurs for both drugs. Since carbonate inhibits the binding of aged carboplatin and cisplatin to DNA, carbonate present in the body likely modulates the reactivity of these drugs with a variety of biological targets including DNA.

Modification of carboplatin by Jurkat cells.

Using [(1)H,(15)N] heteronuclear single quantum coherance (HSQC) NMR and (15)N-labeled carboplatin, 1, we show that Jurkat cells affect the rate of disappearance of the HSQC NMR peak in culture medium for this Pt(2+) anticancer drug. The decay or disappearance rate constant for 1 in culture medium containing cells is k(1)=k(c)[CO(3)(2-)]+k(m)+k(u)N, where k(c) is the rate constant for reaction of 1 with carbonate in the medium, k(m) is the rate constant for reaction of 1 with all other components of the medium, and k(u) is the rate constant for reaction of 1 with cells having a number density N in the medium. Since Jurkat cells only take up a small amount of the platinum present in the medium (<1%), the observed disappearance of the HSQC NMR peak for 1 cannot be due to uptake of carboplatin by the cells.