Enhanced oral bioavailability and antitumor therapeutic efficacy of sorafenib administered in core-shell protein nanoparticle

Biopharmaceutical and pharmacokinetic attributes to drive nanoformulations of small molecule tyrosine kinase inhibitors

Buoyed by the discovery of small-molecule tyrosine kinase inhibitors (smTKIs), significant impact has been made in cancer chemotherapeutics. However, some of these agents still encounter off-target toxicities and suboptimal efficacies due to their inferior biopharmaceutical and/or pharmacokinetic properties. Almost all of these molecules exhibit significant inter- and intra-patient variations in plasma concentration-time profiles. Thus, therapeutic drug monitoring, dose adjustments and precision medicine are being contemplated by clinicians. Complex formulations or nanoformulation-based drug delivery systems offer promising approaches to provide drug encapsulation or spatiotemporal control over the release, overcoming the biopharmaceutical and pharmacokinetic limitations and improving the therapeutic outcomes. In this context, the present review comprehensively tabulates and critically analyzes all the relevant properties (T1/2, solubility, pKa, therapeutic index, IC50, metabolism etc.) of the approved smTKIs. A detailed appraisal is conducted on the advancements made in complex formulations of smTKIs, with a focus on strategies to enhance their pharmacokinetic profile, tumor targeting ability, and therapeutic efficacy. Various nanocarrier platforms, have been discussed, highlighting their unique features and potential applications in cancer therapy. Nanoformulations have been shown to improve area under the curve and peak plasma concentration, and reduce dosing frequency for several smTKIs in animal models. It is inferred that extensive efforts will be made in developing complex formulations of smTKIs in near future. There, the review concludes with key recommendations for the developing of smTKIs to facilitate early clinical translation.

Enhanced anti-tumor therapy for hepatocellular carcinoma via sorafenib and KIAA1199-siRNA co-delivery liposomes

Hepatocellular carcinoma (HCC) is one of the most lethal malignancies worldwide. Sorafenib (Sf) is currently the first-line treatment for HCC. However, due to the side effects and unsatisfied efficiency of Sf, it is urgent to combine different therapeutic agents to inhibit HCC progression and increase the therapeutic efficacy. Here, our study constructed a Sf and KIAA1199-siRNA co-loaded liposome Sf-Lp-KIAA, which was prepared by electrostatic interaction of KIAA1199-siRNA and Sf loaded liposome (Sf-Lp). The particle size, zeta potential, the in vitro cumulative release was investigated. The physical and chemical properties were characterized, and the inhibition of HepG2 growth and metastasis in vitro was investigated. The cellular uptake of the co-loaded liposome was significantly higher than that of free siRNA, and the drug/siRNA could be co-delivered to the target cells. Sf-Lp-KIAA could significantly inhibit the growth, migration, invasion and down-regulate KIAA1199 expression of HepG2 cells in vitro than that of single Sf treated group. In addition, the co-delivery liposome accumulated in the HepG2 subcutaneous tumor model and suppress tumor growth after systemic administration without induce obvious toxicity. The present study implied that the co-delivery of Sf and KIAA1199-siRNA through the co-loaded liposomes exerted synergistic antitumor effects on HCC, which would lay a foundation for HCC therapy in the future.

Intratumor Mycoplasma promotes the initiation and progression of hepatocellular carcinoma

The carcinogenesis and progression of hepatocellular carcinoma (HCC) are closely related to viral infection and intestinal bacteria. However, little is known about bacteria within the HCC tumor microenvironment. Here, we showed that intratumoral Mycoplasma hyorhinis (M. hyorhinis) promoted the initiation and progression of HCC by enhancing nuclear ploidy. We quantified M. hyorhinis in clinical tissue specimens of HCC and observed that patients with high M. hyorhinis load had poor prognosis. We found that gastrointestinal M. hyorhinis can retrogradely infect the liver through the oral-duodenal-hepatopancreatic ampulla route. We further found that the increases in mononuclear polyploidy and cancer stemness resulted from mitochondrial fission caused by intracellular M. hyorhinis. Mechanistically, M. hyorhinis infection promoted the decay of mitochondrial fusion protein (MFN) 1 mRNA in an m6A-dependent manner. Our findings indicated that M. hyorhinis infection promoted pathological polyploidization and suggested that Mycoplasma clearance with antibiotics or regulating mitochondrial dynamics might have the potential for HCC therapy.

Bentonite as a water-insoluble amorphous solid dispersion matrix for enhancing oral bioavailability of poorly water-soluble drugs

Bentonite (BT), an orally administrable natural clay, is widely used for medical and pharmaceutical purposes due to its unique properties, including swelling, adsorption and ion-exchange. However, its application as a matrix of amorphous solid dispersion (ASD) formulations is rarely reported, despite the fact that drugs can adsorb to BT in an amorphous state. The objective of this study was to explore the feasibility of BT as a water-insoluble ASD matrix for enhancing the oral bioavailability of poorly water-soluble drugs, including sorafenib (SF). We prepared a novel BT-based ASD of an SF-BT composite (SFBTC) by adsorbing SF onto BT under acidic conditions using the ionic interaction between cationic SF and negatively charged BT. Scanning electron microscopy (SEM), powder X-ray diffractometry (pXRD), and differential scanning calorimetry (DSC) analyses revealed that SF adsorbed to BT in an amorphous state at SF:BT ratios from 1:3 to 1:10. In pharmacokinetic studies in rats, SFBTC (1:3) significantly improved the oral bioavailability of SF, and the AUClast of SFBTC (1:3) was 3.3-fold higher than that of NEXAVAR®, a commercial product of SF. An in vitro release study under sink conditions revealed that SFBTC (1:3) completely released SF in a pH-dependent manner, while a nonsink condition study indicated the generation of supersaturation under intestinal pH conditions. A kinetic solubility study showed that the release of SFBTC (1:3) followed the diffusion-controlled mechanism, which is a typical characteristic of water-insoluble matrix-based ASDs. The pharmacokinetic studies of drug-BT composites of various drugs belonging to BCS class II indicated that the pKa value of the adsorbed drugs is one of the most important factors determining their dissolution and oral bioavailability. These results suggest that BT could be a promising water-insoluble ASD matrix for improving the oral bioavailability of poorly water-soluble drugs, including SF.

Kaempferide exhibits an anticancer effect against hepatocellular carcinoma in vitro and in vivo

CONTEXT

Phytochemicals have been promising candidates for cancer therapy, affecting various cancer initiation and progression stages. Kaempferide is a mono methoxy flavone that shows potent anticancer effects on multiple cancers both in vitro and in vivo.

MATERIALS AND METHODS

We evaluated the anticancer activity of kaempferide against HCC using an MTT ((3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay. HepG2, Huh7, and N1S1 were used for preliminary in vitro studies. This is followed by an apoptosis analysis assessed by caspase-3 and 9. The in vivo effects of the compound were studied in the N1S1 orthotopically injected SD (Sprague Dawley) rat model, where the animal was given kaempferide (25 mg/kg thrice a week) and vehicle (Cremophor:ethanol) iv. The expression of caspase-9 and a critical tumor marker, transforming growth factor beta 1 (TGF-β 1), were assessed in both control and treatment tumor samples.

RESULTS

Kaempferide-induced dose-dependent cytotoxicity in three HCC cell lines (HepG2: IC50 = 27.94 ± 2.199 µM; Huh7: IC50 = 25.65 ± 0.956 µM; and N1S1: IC50 = 15.18 ± 3.68 µM). Furthermore, caspase-dependent apoptosis was confirmed in vitro. Kaempferide showed a significant reduction in tumor size and tumor volume in vivo. Histopathological evaluation by hematoxylin and eosin (H&E) staining confirmed that altered cells were significantly demolished in the kaempferide-treated animals, which correlates with tumor reduction compared to the vehicle-treated group. Caspase-9 levels were also found to be increased in the treatment group. TGF-β 1, a crucial marker in invasion and metastasis of liver cancer, was also downregulated in the treatment group (control = 207.8 ± 22.9 pg/mL and kaempferide-treated = 157.3 ± 13.8 pg/mL).

CONCLUSION

We report for the first time the potential of kaempferide as a promising alternative against HCC, which further warrants its clinical validation.

CD44 targeted delivery of hyaluronic acid-coated polymeric nanoparticles against colorectal cancer

Aim: To develop hyaluronic acid (HA)-coated poly-lactic-co-glycolic acid (PLGA)-polysarcosine (PSAR) coupled sorafenib tosylate (SF) polymeric nanoparticles for targeted colon cancer therapy. Materials & methods: PLGA-PSAR shells were encapsulated with SF via nanoprecipitation. Interactions were examined with transmission electron microscopy, revealing formulation component interactions. Results: The optimized HA-coated polymeric nanoparticles (238.8 nm, -6.1 mV, 68.361% entrapment) displayed enhanced controlled release of SF. These formulations showed superior cytotoxicity against HCT116 cell lines compared with free drug (p < 0.05). In vivo tests on male albino Wistar rats demonstrated improved pharmacokinetics, targeting and biocompatibility. HA-coated PLGA-PSAR-coupled SF polymeric nanoparticles hold potential for effective colorectal therapy. Conclusion: Colon cancer may be precisely targeted by HA-coated PLGA-PSA-coupled SF polymeric nanoparticles.

Sorafenib-Based Drug Delivery Systems: Applications and Perspectives

As a Food and Drug Administration (FDA)-approved molecular-targeted chemotherapeutic drug, sorafenib (SF) can inhibit angiogenesis and tumor cell proliferation, leading to improved patient overall survival of hepatocellular carcinoma (HCC). In addition, SF is an oral multikinase inhibitor as a single-agent therapy in renal cell carcinoma. However, the poor aqueous solubility, low bioavailability, unfavorable pharmacokinetic properties and undesirable side effects (anorexia, gastrointestinal bleeding, and severe skin toxicity, etc.) seriously limit its clinical application. To overcome these drawbacks, the entrapment of SF into nanocarriers by nanoformulations is an effective strategy, which delivers SF in a target tumor with decreased adverse effects and improved treatment efficacy. In this review, significant advances and design strategies of SF nanodelivery systems from 2012 to 2023 are summarized. The review is organized by type of carriers including natural biomacromolecule (lipid, chitosan, cyclodextrin, etc.); synthetic polymer (poly(lactic-co-glycolic acid), polyethyleneimine, brush copolymer, etc.); mesoporous silica; gold nanoparticles; and others. Co-delivery of SF and other active agents (glypican-3, hyaluronic acid, apolipoprotein peptide, folate, and superparamagnetic iron oxide nanoparticles) for targeted SF nanosystems and synergistic drug combinations are also highlighted. All these studies showed promising results for targeted treatment of HCC and other cancers by SF-based nanomedicines. The outlook, challenges and future opportunities for the development of SF-based drug delivery are presented.

5-FU mediated depletion of myeloid suppressor cells enhances T-cell infiltration and anti-tumor response in immunotherapy-resistant lung tumor

Tumor microenvironment (TME) is a heterogeneous system consisting of both cellular and acellular components. The growth and progression of tumors rely greatly on the nature of TME, marking it as an important target in cancer immunotherapy. Lewis Lung Carcinoma (LLC) is an established murine lung cancer model representing immunologically 'cold' tumors characterized by very few infiltrated cytotoxic T-cells, high levels of Myeloid-Derived Suppressor Cells (MDSCs) and Tumor-Associated Macrophages (TAMs). Here, we report various strategies we applied to reverse the non-immunogenic character of this cold tumor by imparting: a) immunogenic cell death using Hypericin nanoparticle-based photodynamic therapy (PDT), b) repolarising TAM using a TLR7/8 agonist, resiquimod, c) immune checkpoint inhibition using anti-PD-L1 and d) depleting MDSCs using low-dose 5-fluorouracil (5-FU) chemotherapy. Interestingly, the nano-PDT, resiquimod or anti-PD-L1 treatment had no major impact on tumor growth, whereas low-dose 5-FU-mediated depletion of MDSCs showed significant anti-tumor effect, primarily caused by the increased infiltration of CD8⁺ cytotoxic T-cells (∼96%). Though we have tested combining PDT with resiquimod or 5-FU for any synergistic effect, low-dose 5-FU alone showed better response than combinations. In effect, we show that depletion of MDSCs using low-dose 5-FU was one of the best methods to augment infiltration of CD8⁺ cytotoxic T-cells into a cold tumor, which is resistant to conventional therapies including immune checkpoint inhibitors.

Intracranial nanomedicine-gel with deep brain-penetration for glioblastoma therapy

Glioblastoma Multiforme (GBM) is one of the challenging tumors to treat as it recurs, almost 100%, even after surgery, radiation, and chemotherapy. In many cases, recurrence happens within 2-3cm depth of the resected tumor margin, indicating the inefficacy of current anti-glioma drugs to penetrate deep into the brain tissue. Here, we report an injectable nanoparticle-gel system, capable of providing deep brain penetration of drug up to 4 cm, releasing in a sustained manner up to >15 days. The system consists of ∼222 nm sized PLGA nanoparticles (NP-222) loaded with an anti-glioma drug, Carmustine (BCNU), and coated with a thick layer of polyethylene glycol (PEG). Upon release of the drug from PLGA core, it will interact with the outer PEG-layer leading to the formation of PEG-BCNU nanocomplexes of size ∼33 nm (BCNU-NC-33), which could penetrate >4 cm deep into the brain tissue compared to the free drug (< 5 mm). In vitro drug release showed sustained release of drug for 15 days by BCNU-NP gel, and enhanced cytotoxicity by BCNU-NC-33 drug-nanocomplexes in glioma cell lines. Ex vivo goat-brain phantom studies showed drug diffusion up to 4 cm in tissue and in vivo brain-diffusion studies showed almost complete coverage within the rat brain (∼1.2 cm), with ∼55% drug retained in the tissue by day-15, compared to only ∼5% for free BCNU. Rat orthotopic glioma studies showed excellent anti-tumor efficacy by BCNU-NP gel compared to free drug, indicating the potential of the gel-system for anti-glioma therapy. In effect, we demonstrate a unique method of sustained release of drug in the brain using larger PLGA nanoparticles acting as a reservoir while deep-penetration of the released drug was achieved by in situ formation of drug-nanocomplexes of size <50 nm which is less than the native pore size of brain tissue (> 100 nm). This method will have a major impact on a challenging field of brain drug delivery.

Enhanced oral bioavailability from food protein nanoparticles: A mini review

The oral route is the most desirable drug administration path. The oral bioavailability is always compromised from the poor physicochemical and/or biopharmaceutical properties of the active pharmaceutical ingredients. Food protein nanoparticles show promise for oral drug delivery, with improved biosafety and cost-effectiveness compared to polymeric nanoparticles. More importantly, diverse food proteins provide "choice and variety" to meet the challenges faced by different drugs in oral delivery resulting from low solubility, poor permeability, and gastrointestinal stability. The abundance of hydroxyl, amino, and carboxyl groups in food proteins allows easy surface modification of the nanoparticles to impart unique functions. Albeit being in its infancy, food protein nanoparticles exhibit high capability to enhance oral bioavailability of a wide range of drugs from small molecules to biomacromolecules. Considering the rapid growth of the field, the achievements and mechanisms of food protein nanoparticles in enhancing oral bioavailability are reviewed. Factors affecting the performance of food protein nanoparticles are discussed with the purpose to inspire the development of food protein nanoparticle-based oral drug delivery systems.

High Drug Loading Nanoparticles Stabilized with Autologous Serum Proteins Passively Inhibits Tumor Growth

We report drug nanocrystals stabilized with host-specific serum proteins with high loading (∼63% w/w). The human serum derived curcumin nanoparticles (Cur-NanoSera) showed superior in vitro anticancer efficiency compared to a free drug with substantial hemocompatibility. The preadsorbed protein coating impeded further protein corona formation, even with repeated serum exposures. Acute and subacute toxicity evaluations post single and dual injections of C57BL/6 mice indicated that Cur-NanoSera showed no prominent inflammatory response or organ damage in the in-bred mice. Passive accumulation of Cur-NanoSera in tumor tissue significantly suppressed its growth in a syngeneic breast tumor model in addition to controlling tumor burden associated splenomegaly.