Closed-loop automated drug infusion regulator: A clinically translatable, closed-loop drug delivery system for personalized drug dosing.

BACKGROUND: Dosing of chemotherapies is often calculated according to the weight and/or height of the patient or equations derived from these, such as body surface area (BSA). Such calculations fail to capture intra- and interindividual pharmacokinetic variation, which can lead to order of magnitude variations in systemic chemotherapy levels and thus under- or overdosing of patients. METHODS: We designed and developed a closed-loop drug delivery system that can dynamically adjust its infusion rate to the patient to reach and maintain the drug's target concentration, regardless of a patient's pharmacokinetics (PK). FINDINGS: We demonstrate that closed-loop automated drug infusion regulator (CLAUDIA) can control the concentration of 5-fluorouracil (5-FU) in rabbits according to a range of concentration-time profiles (which could be useful in chronomodulated chemotherapy) and over a range of PK conditions that mimic the PK variability observed clinically. In one set of experiments, BSA-based dosing resulted in a concentration 7 times above the target range, while CLAUDIA keeps the concentration of 5-FU in or near the targeted range. Further, we demonstrate that CLAUDIA is cost effective compared to BSA-based dosing. CONCLUSIONS: We anticipate that CLAUDIA could be rapidly translated to the clinic to enable physicians to control the plasma concentration of chemotherapy in their patients. FUNDING: This work was supported by MIT's Karl van Tassel (1925) Career Development Professorship and Department of Mechanical Engineering and the Bridge Project, a partnership between the Koch Institute for Integrative Cancer Research at MIT and the Dana-Farber/Harvard Cancer Center.

Profiling of Circulating Tumor Cells for Screening of Selective Inhibitors of Tumor-Initiating Stem-Like Cells.

A critical barrier to effective cancer therapy is the improvement of drug selectivity, toxicity, and reduced recurrence of tumors expanded from tumor-initiating stem-like cells (TICs). The aim is to identify circulating tumor cell (CTC)-biomarkers and to identify an effective combination of TIC-specific, repurposed federal drug administration (FDA)-approved drugs. Three different types of high-throughput screens targeting the TIC population are employed: these include a CD133 (+) cell viability screen, a NANOG expression screen, and a drug combination screen. When combined in a refined secondary screening approach that targets Nanog expression with the same FDA-approved drug library, histone deacetylase (HDAC) inhibitor(s) combined with all-trans retinoic acid (ATRA) demonstrate the highest efficacy for inhibition of TIC growth in vitro and in vivo. Addition of immune checkpoint inhibitor further decreases recurrence and extends PDX mouse survival. RNA-seq analysis of TICs reveals that combined drug treatment reduces many Toll-like receptors (TLR) and stemness genes through repression of the lncRNA MIR22HG. This downregulation induces PTEN and TET2, leading to loss of the self-renewal property of TICs. Thus, CTC biomarker analysis would predict the prognosis and therapy response to this drug combination. In general, biomarker-guided stratification of HCC patients and TIC-targeted therapy should eradicate TICs to extend HCC patient survival.

Development of oil-based gels as versatile drug delivery systems for pediatric applications.

Administering medicines to 0- to 5-year-old children in a resource-limited environment requires dosage forms that circumvent swallowing solids, avoid on-field reconstitution, and are thermostable, cheap, versatile, and taste masking. We present a strategy that stands to solve this multifaceted problem. As many drugs lack adequate water solubility, our formulations used oils, whose textures could be modified with gelling agents to form "oleogels." In a clinical study, we showed that the oleogels can be formulated to be as fluid as thickened beverages and as stiff as yogurt puddings. In swine, oleogels could deliver four drugs ranging three orders of magnitude in their water solubilities and two orders of magnitude in their partition coefficients. Oleogels could be stabilized at 40°C for prolonged durations and used without redispersion. Last, we developed a macrofluidic system enabling fixed and metered dosing. We anticipate that this platform could be adopted for pediatric dosing, palliative care, and gastrointestinal disease applications.

Personalized Radiation Attenuating Materials for Gastrointestinal Mucosal Protection.

Cancer patients undergoing therapeutic radiation routinely develop injury of the adjacent gastrointestinal (GI) tract mucosa due to treatment. To reduce radiation dose to critical GI structures including the rectum and oral mucosa, 3D-printed GI radioprotective devices composed of high-Z materials are generated from patient CT scans. In a radiation proctitis rat model, a significant reduction in crypt injury is demonstrated with the device compared to without (p < 0.0087). Optimal device placement for radiation attenuation is further confirmed in a swine model. Dosimetric modeling in oral cavity cancer patients demonstrates a 30% radiation dose reduction to the normal buccal mucosa and a 15.2% dose reduction in the rectum for prostate cancer patients with the radioprotectant material in place compared to without. Finally, it is found that the rectal radioprotectant device is more cost-effective compared to a hydrogel rectal spacer. Taken together, these data suggest that personalized radioprotectant devices may be used to reduce GI tissue injury in cancer patients undergoing therapeutic radiation.

Computationally guided high-throughput design of self-assembling drug nanoparticles.

Nanoformulations of therapeutic drugs are transforming our ability to effectively deliver and treat a myriad of conditions. Often, however, they are complex to produce and exhibit low drug loading, except for nanoparticles formed via co-assembly of drugs and small molecular dyes, which display drug-loading capacities of up to 95%. There is currently no understanding of which of the millions of small-molecule combinations can result in the formation of these nanoparticles. Here we report the integration of machine learning with high-throughput experimentation to enable the rapid and large-scale identification of such nanoformulations. We identified 100 self-assembling drug nanoparticles from 2.1 million pairings, each including one of 788 candidate drugs and one of 2,686 approved excipients. We further characterized two nanoparticles, sorafenib-glycyrrhizin and terbinafine-taurocholic acid both ex vivo and in vivo. We anticipate that our platform can accelerate the development of safer and more efficacious nanoformulations with high drug-loading capacities for a wide range of therapeutics.

Local Targeting of NAD+ Salvage Pathway Alters the Immune Tumor Microenvironment and Enhances Checkpoint Immunotherapy in Glioblastoma.

The aggressive primary brain tumor glioblastoma (GBM) is characterized by aberrant metabolism that fuels its malignant phenotype. Diverse genetic subtypes of malignant glioma are sensitive to selective inhibition of the NAD+ salvage pathway enzyme nicotinamide phosphoribosyltransferase (NAMPT). However, the potential impact of NAD+ depletion on the brain tumor microenvironment has not been elaborated. In addition, systemic toxicity of NAMPT inhibition remains a significant concern. Here we show that microparticle-mediated intratumoral delivery of NAMPT inhibitor GMX1778 induces specific immunologic changes in the tumor microenvironment of murine GBM, characterized by upregulation of immune checkpoint PD-L1, recruitment of CD3+, CD4+, and CD8+ T cells, and reduction of M2-polarized immunosuppressive macrophages. NAD+ depletion and autophagy induced by NAMPT inhibitors mediated the upregulation of PD-L1 transcripts and cell surface protein levels in GBM cells. NAMPT inhibitor modulation of the tumor immune microenvironment was therefore combined with PD-1 checkpoint blockade in vivo, significantly increasing the survival of GBM-bearing animals. Thus, the therapeutic impacts of NAMPT inhibition extended beyond neoplastic cells, shaping surrounding immune effectors. Microparticle delivery and release of NAMPT inhibitor at the tumor site offers a safe and robust means to alter an immune tumor microenvironment that could potentiate checkpoint immunotherapy for glioblastoma. SIGNIFICANCE: Microparticle-mediated local inhibition of NAMPT modulates the tumor immune microenvironment and acts cooperatively with anti-PD-1 checkpoint blockade, offering a combination immunotherapy strategy for the treatment of GBM.

Machine Learning Uncovers Food- and Excipient-Drug Interactions.

Inactive ingredients and generally recognized as safe compounds are regarded by the US Food and Drug Administration (FDA) as benign for human consumption within specified dose ranges, but a growing body of research has revealed that many inactive ingredients might have unknown biological effects at these concentrations and might alter treatment outcomes. To speed up such discoveries, we apply state-of-the-art machine learning to delineate currently unknown biological effects of inactive ingredients-focusing on P-glycoprotein (P-gp) and uridine diphosphate-glucuronosyltransferase-2B7 (UGT2B7), two proteins that impact the pharmacokinetics of approximately 20% of FDA-approved drugs. Our platform identifies vitamin A palmitate and abietic acid as inhibitors of P-gp and UGT2B7, respectively; in silico, in vitro, ex vivo, and in vivo validations support these interactions. Our predictive framework can elucidate biological effects of commonly consumed chemical matter with implications on food- and excipient-drug interactions and functional drug formulation development.

Perlecan-targeted nanoparticles for drug delivery to triple-negative breast cancer.

AIM: We previously developed two antibodies that bind to a cell surface protein, perlecan, overexpressed in triple-negative breast cancer (TNBC). The goal of this study was to investigate these antibodies as targeting ligands for nanoparticle-mediated drug delivery. METHODS: Paclitaxel-loaded poly(D,L-lactide-co-glycolide) nanoparticles were functionalized with antibodies using thiol-maleimide chemistry. Effect of antibody functionalization on therapeutic efficacy of drug-loaded nanoparticles was investigated using in vitro and in vivo models of TNBC. RESULTS: The antibodies were covalently conjugated to nanoparticles without affecting antibody binding affinity or nanoparticle properties. Perlecan-targeted nanoparticles showed improved cell uptake, retention, cytotoxicity in vitro and enhanced tumor growth inhibition in vivo. CONCLUSION: The data presented here indicates that perlecan-targeted nanoparticles can improve tumor drug delivery to TNBC.

Chemopreventive efficacy of oral curcumin: a prodrug hypothesis.

Oral consumption of curcumin, a natural polyphenol, is associated with reduced incidence of cancer. Yet, a significant amount of the orally dosed compound is eliminated in the feces, and a major fraction of the absorbed compound is metabolized to inactive glucuronides, resulting in poor bioavailability (<1%). It is not known how oral curcumin exhibits chemopreventive activity. We propose curcumin glucuronide is an inflammation-responsive natural prodrug that is converted back to curcumin on demand at the site of action. Our studies show elevated levels of ß-glucuronidase, an enzyme that hydrolyzes the glycosidic bond of glucuronides to generate the parent compound, in human breast cancer. Oral administration of curcumin in mouse tumor models generated significant tumor levels of the polyphenol. Intravenous administration of the glucuronide resulted in the formation of curcumin in the tumor tissue. Chronic daily oral curcumin dosing led to tumor accumulation of curcumin and inhibition of tumor growth in tumor models with high ß-glucuronidase activity. Overall, the study presented here provides preliminary evidence for a novel mechanism of action for orally administered curcumin.-Liu, G., Khanna, V., Kirtane, A., Grill, A., Panyam, J. Chemopreventive efficacy of oral curcumin: a prodrug hypothesis.

Genotype-targeted local therapy of glioma.

Aggressive neurosurgical resection to achieve sustained local control is essential for prolonging survival in patients with lower-grade glioma. However, progression in many of these patients is characterized by local regrowth. Most lower-grade gliomas harbor isocitrate dehydrogenase 1 (IDH1) or IDH2 mutations, which sensitize to metabolism-altering agents. To improve local control of IDH mutant gliomas while avoiding systemic toxicity associated with metabolic therapies, we developed a precision intraoperative treatment that couples a rapid multiplexed genotyping tool with a sustained release microparticle (MP) drug delivery system containing an IDH-directed nicotinamide phosphoribosyltransferase (NAMPT) inhibitor (GMX-1778). We validated our genetic diagnostic tool on clinically annotated tumor specimens. GMX-1778 MPs showed mutant IDH genotype-specific toxicity in vitro and in vivo, inducing regression of orthotopic IDH mutant glioma murine models. Our strategy enables immediate intraoperative genotyping and local application of a genotype-specific treatment in surgical scenarios where local tumor control is paramount and systemic toxicity is therapeutically limiting.

Triptolide suppresses the in vitro and in vivo growth of lung cancer cells by targeting hyaluronan-CD44/RHAMM signaling.

Higher levels of hyaluronan (HA) and its receptors CD44 and RHAMM have been associated with poor prognosis and metastasis in NSCLC. In the current study, our goal was to define, using cellular and orthotopic lung tumor models, the role of HA-CD44/RHAMM signaling in lung carcinogenesis and to assess the potential of triptolide to block HA-CD44/RHAMM signaling and thereby suppress the development and progression of lung cancer. Triptolide reduced the viability of five non-small cell lung cancer (NSCLC) cells, the proliferation and self-renewal of pulmospheres, and levels of HA synthase 2 (HAS2), HAS3, HA, CD44, RHAMM, EGFR, Akt and ERK, but increased the cleavage of caspase 3 and PARP. Silencing of HAS2, CD44 or RHAMM induced similar effects. Addition of excess HA to the culture media completely abrogated the effects of triptolide and siRNAs targeting HAS2, CD44, or RHAMM. In an orthotopic lung cancer model in nude rats, intranasal administration of liposomal triptolide (400 µg/kg) for 8 weeks significantly reduced lung tumor growth as determined by bioluminescence imaging, lung weight measurements and gross and histopathological analysis of tumor burden. Also, triptolide suppressed expressions of Ki-67, a marker for cell proliferation, HAS2, HAS3, HA, CD44, and RHAMM in lung tumors. Overall, our results provide a strong rationale for mitigating lung cancer by targeting the HA-CD44/RHAMM signaling axis.

Fibrinolytic Enzyme Cotherapy Improves Tumor Perfusion and Therapeutic Efficacy of Anticancer Nanomedicine.

Elevated interstitial fluid pressure and solid stress within tumors contribute to poor intratumoral distribution of nanomedicine. In this study, we hypothesized that the presence of fibrin in tumor extracellular matrix contributes to hindered intratumoral distribution of nanocarriers and that this can be overcome through the use of a fibrinolytic enzyme such as tissue plasminogen activator (tPA). Analysis of fibrin expression in human tumor biopsies showed significant fibrin staining in nearly all tumor types evaluated. However, staining was heterogeneous across and within tumor types. We determined the effect of fibrin on the diffusion, intratumoral distribution, and therapeutic efficacy of nanocarriers. Diffusivity of nanocarriers in fibrin matrices was limited and could be improved significantly by coincubation with tPA. In vivo, coadministration of tPA improved the anticancer efficacy of nanoparticle-encapsulated paclitaxel in subcutaneous syngeneic mouse melanoma and orthotopic xenograft lung cancer models. Furthermore, treatment with tPA led to decompression of blood vessels and improved tumor perfusion. Cotreatment with tPA resulted in greater intratumoral penetration of a model nanocarrier (Doxil), leading to enhanced availability of the drug in the tumor core. Fibrinolytics such as tPA are already approved for other indications. Fibrinolytic cotherapy is therefore a rapidly translatable strategy for improving therapeutic effectiveness of anticancer nanomedicine. Cancer Res; 77(6); 1465-75. ©2017 AACR.

Assessing the Benefits of Drug Delivery by Nanocarriers: A Partico/Pharmacokinetic Framework.

OBJECTIVE: An in vivo kinetic framework is introduced to analyze and predict the quantitative advantage of using nanocarriers to deliver drugs, especially anticancer agents, compared to administering the same drugs in their free form. METHODS: This framework recognizes three levels of kinetics. First is the particokinetics associated with deposition of nanocarriers into tissues associated with drug effect and toxicity, their residence inside those tissues, and elimination of the nanocarriers from the body. Second is the release pattern in time of free drug from the nanocarriers. Third is the pharmacokinetics of free drug, as it relates to deposition and elimination processes in the target and toxicity associated tissues, and total body clearance. A figure of merit, the drug targeting index (DTI), is used to quantitate the benefit of nanocarrier-based drug delivery by considering the effects of preferential deposition of nanoparticles into target tissues and relative avoidance of tissues associated with drug toxicity, compared to drug that is administered in its free form. RESULTS: General methods are derived for calculating DTI when appropriate particokinetic, pharmacokinetic, and drug release rate information is available, and it is shown that relatively simple algebraic forms result when some common assumptions are made. CONCLUSION: This approach may find use in developing and selecting nanocarrier formulations, either for populations or for individuals.

Honokiol suppresses lung tumorigenesis by targeting EGFR and its downstream effectors.

Since epidermal growth factor receptor (EGFR) is commonly deregulated in pre-malignant lung epithelium, targeting EGFR may arrest the development of lung cancer. Here, we showed that honokiol (2.5-7.5 µM), a bioactive compound of Magnolia officinalis, differentially suppressed proliferation (up to 93%) and induced apoptosis (up to 61%) of EGFR overexpressing tumorigenic bronchial cells and these effects were paralleled by downregulation of phospho-EGFR, phospho-Akt, phospho-STAT3 and cell cycle-related proteins as early as 6-12 h post-treatment. Autocrine secretion of EGF sensitized 1170 cells to the effects of honokiol. Molecular docking studies indicated that honokiol binds to the tyrosine kinase domain of EGFR although it was less efficient than erlotinib. However, the anti-proliferative and pro-apoptotic activities of honokiol were stronger than those of erlotinib. Upon combinatory treatment, honokiol sensitized bronchial cells and erlotinib resistant H1650 and H1975 cells to erlotinib. Furthermore, in a mouse lung tumor bioassay, intranasal instillation of liposomal honokiol (5 mg/kg) for 14 weeks reduced the size and multiplicity (49%) of lung tumors and the level of total- and phospho-EGFR, phospho-Akt and phospho-STAT3. Overall, our results indicate that honokiol is a promising candidate to suppress the development and even progression of lung tumors driven by EGFR deregulation.

Reformulating Tylocrebrine in Epidermal Growth Factor Receptor Targeted Polymeric Nanoparticles Improves Its Therapeutic Index.

Several promising anticancer drug candidates have been sidelined owing to their poor physicochemical properties or unfavorable pharmacokinetics, resulting in high overall cost of drug discovery and development. Use of alternative formulation strategies that alleviate these issues can help advance new molecules to the clinic at a significantly lower cost. Tylocrebrine is a natural product with potent anticancer activity. Its clinical trial was discontinued following the discovery of severe central nervous system toxicities. To improve the safety and potency of tylocrebrine, we formulated the drug in polymeric nanoparticles targeted to the epidermal growth factor receptor (EGFR) overexpressed on several types of tumors. Through in vitro studies in different cancer cell lines, we found that EGFR targeted nanoparticles were significantly more effective in killing tumor cells than the free drug. In vivo pharmacokinetic studies revealed that encapsulation in nanoparticles resulted in lower brain penetration and enhanced tumor accumulation of the drug. Further, targeted nanoparticles were characterized by significantly enhanced tumor growth inhibitory activity in a mouse xenograft model of epidermoid cancer. These results suggest that the therapeutic index of drugs that were previously considered unusable could be significantly improved by reformulation. Application of novel formulation strategies to previously abandoned drugs provides an opportunity to advance new molecules to the clinic at a lower cost. This can significantly increase the repertoire of treatment options available to cancer patients.

A pharmacokinetic model for quantifying the effect of vascular permeability on the choice of drug carrier: a framework for personalized nanomedicine.

Drug carriers in the ∼ 100 nm size range are of considerable interest in the field of cancer therapy because of their ability to passively accumulate in tumors. Tailoring the physicochemical properties of these carriers to individual patient requirements will help exploit their full therapeutic potential. Here, we present a pharmacokinetic model to explain how vascular physiology could be used to guide the optimal choice of specific formulation parameters. We find that in order to maximize the benefit-to-risk ratio, nanosystems should be confined to a specific particle size range. The optimal particle size range is dictated by the vascular pore size of not only the tumor tissue but also of the normal organs. Additionally, the duration of drug release is a key variable that can be used to maximize the therapeutic benefit of nanomedicine. Our model further suggests that the enhanced permeability and retention effect is not necessarily a universal outcome for every nanocarrier in every tumor model but will only be observed for nanoparticles of a specific size range. This optimal size range, in turn, is governed by the vascular physiology of the tumor and of non-target organs.

Intranasal delivery of liposomal indole-3-carbinol improves its pulmonary bioavailability.

Indole-3-carbinol (I3C), a constituent of commonly consumed Brassica vegetables, has been shown to have anticancer effects in a variety of preclinical models of lung cancer. However, it has shown only limited efficacy in clinical trials, likely due to its poor oral bioavailability. Intranasal administration of I3C has the potential to enhance the pulmonary accumulation of the drug, thereby improving its availability at the target site of action. In this study, we developed a liposomal formulation of I3C and evaluated its lung delivery and chemopreventive potential in tobacco smoke carcinogen [4-(methylnitro-samino)-1-(3-pyridyl)-1-butanone (NNK)]-treated mice. Intranasal administration of I3C liposomes led to a ∼100-fold higher lung exposure of I3C than the oral route of administration. Further, intranasal delivery of liposomal I3C led to a significant reduction (37%; p<0.05) in the levels of the DNA adduct formation induced by NNK treatment. Liposomal I3C also significantly increased (by 10-fold) the expression of CYP1A1, a cytochrome P450 enzyme known to increase the detoxification of chemical carcinogens by enhancing their metabolism. Overall, our findings demonstrate that intranasal administration of liposomal I3C has the potential to significantly improve the efficacy of I3C for lung cancer chemoprevention.

Enhanced photodynamic therapy and effective elimination of cancer stem cells using surfactant-polymer nanoparticles.

Photodynamic therapy is a potentially curative treatment for various types of cancer. It involves energy transfer from an excited photosensitizer to surrounding oxygen molecules to produce cytotoxic singlet oxygen species, a process termed as type II reaction. The efficiency of photodynamic therapy is greatly reduced because of the reduced levels of oxygen, often found in tumor microenvironments that also house cancer stem cells, a subpopulation of tumor cells that are characterized by enhanced tumorigenicity and resistance to conventional therapies. We show here that encapsulation of a photosensitizer, methylene blue, in alginate-Aerosol OT nanoparticles leads to an increased production of reactive oxygen species (ROS) under both normoxic and hypoxic conditions. ROS generation was found to depend on the interaction of the cationic photosensitizer with the anionic alginate polymer. Dye-polymer interaction was characterized by formation of methylene blue dimers, potentially enabling electron transfer and a type I photochemical reaction that is less sensitive to environmental oxygen concentration. We also find that nanoparticle encapsulated methylene blue has the capacity to eliminate cancer stem cells under hypoxic conditions, an important goal of current cancer therapy.

Synthesis, characterization, and evaluation of poly (D,L-lactide-co-glycolide)-based nanoformulation of miRNA-150: potential implications for pancreatic cancer therapy.

MicroRNAs are small (18-22 nucleotide long) noncoding RNAs that play important roles in biological processes through posttranscriptional regulation of gene expression. Their aberrant expression and functional significance are reported in several human malignancies, including pancreatic cancer. Recently, we identified miR-150 as a novel tumor suppressor microRNA in pancreatic cancer. Furthermore, expression of miR-150 was downregulated in the majority of tumor cases, suggesting that its restoration could serve as an effective approach for pancreatic cancer therapy. In the present study, we developed a nanoparticle-based miR-150 delivery system and tested its therapeutic efficacy in vitro. Using double emulsion solvent evaporation method, we developed a poly (D,L-lactide-co-glycolide) (PLGA)-based nanoformulation of miR-150 (miR-150-NF). Polyethyleneimine (a cationic polymer) was incorporated in PLGA matrix to increase the encapsulation of miR-150. Physical characterization of miR-150-NF demonstrated that these nanoparticles had high encapsulation efficiency (~78%) and exhibited sustained release profile. Treatment of pancreatic cancer cells with miR-150-NF led to efficient intracellular delivery of miR-150 mimics and caused significant downregulation of its target gene (MUC4) expression. Inhibition of MUC4 correlated with a concomitant decrease in the expression of its interacting partner, HER2, and repression of its downstream signaling. Furthermore, treatment of pancreatic cancer cells with miR-150-NF suppressed their growth, clonogenicity, motility, and invasion. Together, these findings suggest that PLGA-based nanoformulation could potentially serve as a safe and effective nanovector platform for miR-150 delivery to pancreatic tumor cells.