SW43-DOX ± loading onto drug-eluting bead, a potential new targeted drug delivery platform for systemic and locoregional cancer treatment - An in vitro evaluation

Effect of magnetic microbeads on sustained and targeted delivery of transforming growth factor-beta-1 for rotator cuff healing in a rat rotator cuff repair model

Structural failure is a well-established complication of rotator cuff repair procedures. To evaluate the effect of magnetic microbeads, designed for precise drug delivery via magnetic force, on sustained transforming growth factor-beta-1 (TGF-β1) release and rotator cuff healing in a rat rotator cuff repair model. TGF-β1 laden microbeads were prepared, and baseline in vitro experiments included the magnetization of the microbeads and TGF-β1 release tests. In an in vivo experiment using a rat rotator cuff repair model on both shoulders, 72 rats were randomly assigned to three groups (24 per group): group A, conventional repair; group B, repair with and simple TGF-β1 injection; and group C, repair with magnet insertion into the humeral head and TGF-β1 laden microbead injection. Delivery of TGF-β1 was evaluated at 1 and 7 days after the intervention using PCR, Western blot, and immunohistochemistry. At 6 weeks post-intervention, rotator cuff healing was assessed using biomechanical and histological analysis. The in vitro experiments confirmed the magnetization property of the microbeads and sustained delivery of TGF-β1 for up to 10 days. No difference in the TGF-β1 expression was found at day 1 in vivo. However, at day 7, group C exhibited a significantly elevated expression of TGF-β1 in both PCR and Western blot analyses compared to groups A and B (all P < 0.05). Immunohistochemical analysis revealed a higher expression of TGF-β1 at the repair site in group C on day 7. At 6 weeks, biomechanical analysis demonstrated a significantly higher ultimate failure load in group C than in groups A and B (P < 0.05) and greater stiffness than in group A (P = 0.045). In addition, histological analysis showed denser and more regular collagen fibers with complete continuity to the bone in group C than in groups A and B, a statistically significant difference according to the semi-quantitative scoring system (all P < 0.05). The use of the TGF-β1 laden magnetic microbeads demonstrated sustained delivery of TGF-β1 to the repair site, improving rotator cuff healing.

Preparation and In Vitro Evaluation of a Gadolinium-Containing Vitamin E TPGS Micelle as a Potential Contrast Agent for MR Imaging

The application of many currently evaluated macromolecular contrast agents for magnetic resonance imaging (MRI) has been limited because of their bio-incompatibility and toxicity. The aim of this study is to synthesize and characterize a new micelle-based TPGS gadolinium chelate as a biocompatible MRI contrast agent for prolonged blood circulation time and good tumor imaging contrast. The TPGS-gadolinium conjugate was prepared through the conjugation between TPGS-SA and bifunctional L-NETA-Gd chelate. The conjugate was characterized with regard to molecular weight, critical micellar concentration and particle sizes, cellular uptake, and in vitro cell MRI. Distributions of the MRI contrast agent in various organs were determined via intravenous injection of the agent into mice bearing xenograft tumors. The successfully prepared TPGS-L-NETA-Gd micelle exhibited improved cellular uptake in HepG2 cells and xenografts and high in vivo safety. Distributions of TPGS-L-NETA-Gd in mice showed enhanced cellular uptake up to 2 h after the contrast agent injection. Its in vitro and in vivo properties make it a favorable macromolecular MRI contrast agent for future in vivo imaging.

A Mechanistic Investigation on the Anticancer Properties of SYA013, a Homopiperazine Analogue of Haloperidol with Activity against Triple Negative Breast Cancer Cells

Triple-negative breast cancer (TNBC) is one of the most malignant cancers associated with early metastasis, poor clinical prognosis, and high recurrence rate. TNBC is a distinct subtype of breast cancer that lacks estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor 2 receptors (HER2). Development of effective TNBC therapies has been limited partially due to the lack of specific molecular targets and chemotherapy involving different cytotoxic drugs suffers from significant side effects and drug-resistance development. Therefore, there is an unmet need for the development of novel and efficient therapeutic drugs with reduced side effects to treat TNBC. We have previously reported that certain analogues of haloperidol (a typical antipsychotic drug used for treating mental/mood disorders such as schizophrenia and bipolar disorder) suppress the viability of a variety of solid tumor cell lines, and we have identified 4-(4-(4-chlorophenyl)-1,4-diazepan-1-yl)-1-(4-fluoro-phenyl)butan-1-one (SYA013) with such antiproliferative properties. Interestingly, unlike haloperidol, SYA013 shows moderate selectivity toward σ2 receptors. In this study, we explored the potential of SYA013 in modulating the important biological events associated with cell survival and progression as well as the mechanistic aspects of apoptosis in a representative TNBC cell line (MDA-MB-231). Our results indicate that SYA013 inhibits the proliferation of MDA-MB-231 cells in a concentration-dependent manner and suppresses cell migration and invasion. Apoptotic studies were also conducted in MDA-MB-468 cells (cells derived from a 51-year old Black female with metastatic adenocarcinoma of the breast.). In addition, we have demonstrated that SYA013 induces MDA-MB-231 cell death through the intrinsic apoptotic pathway and may suppress tumor progression and metastasis. Taken together, our study presents a mechanistic pathway of the anticancer properties of SYA013 against TNBC cell lines and suggests a potential for exploring SYA013 as a lead agent for development against TNBC.

Locoregional Therapy, Immunotherapy and the Combination in Hepatocellular Carcinoma: Future Directions

Image-guided locoregional therapies (LRTs) have long been a vital part of treatment regimens for hepatocellular carcinoma (HCC). Ablation, chemoembolization, and radioembolization are examples of commonly used treatment techniques for HCC. This review describes the various methods utilized to treat HCC in the field of interventional oncology and also focuses on new and novel treatment concepts being developed in the field including the use of novel immunotherapy agents and combination therapy of LRTs with immunotherapy.

Sigma-2 receptor: past, present and perspectives on multiple therapeutic exploitations

Identification of sigma-2 receptor (sig-2R) has been controversial. Nevertheless, interest in sig-2R is high for its overexpression in tumors and potentials in oncology. Additionally, sig-2R antagonists inhibit Aβ binding at neurons, blocking the cognitive impairments of Alzheimer's disease. The most representative classes of sig-2R ligands are herein treated with focus on compounds that served to study sig-2R biology and to produce sig-2R: fluorescent ligands; multifunctional anticancer agents; and targeting nanoparticles. Although fluorescent ligands serve as ‘green’ pharmacological tools, sig-2R-multifunctional conjugates and sig-2R-targeted nanoparticles show how sig-2R targeting increases the activity of anticancer drugs in tumors with reduced toxicity. Altogether, this review draws a picture of the multiple approaches of sig-2R ligands in cancer therapy and as Alzheimer's disease modifying disease agents.

Targeted Yttrium 89-Doxorubicin Drug-Eluting Bead-A Safety and Feasibility Pilot Study in a Rabbit Liver Cancer Model

The purpose of this article is to evaluate feasibility and safety of the cancer targeting (radio)-chemoembolization drug-eluting bead (TRCE-DEB) concept drug SW43-DOX-L-NETA(⁸⁹Y) DEB for the intra-arterial treatment of VX2 rabbit liver tumors. The treatment compound comprises of the sigma-2 receptor ligand SW43 for cancer targeting, doxorubicin (DOX), and ⁸⁹yttrium (⁸⁹Y) as nonradioactive surrogate for therapeutic (yttrium-90, lutetium-177) and imaging (yttrium-86) radioisotopes via the chelator L-NETA. Ten New Zealand white rabbits with VX2 tumor allografts were used. SW43-DOX-⁸⁹Y was synthesized, loaded onto DEB (100 μL; 100-300 μm), and administered intra-arterially in six rabbits at increasing doses (0.2-1.0 mg/kg). As controls, two rabbits each received either doxorubicin IV (0.3 mg/kg) or no treatment. Consecutive serum analysis for safety and histopathological evaluation after sacrifice were performed. One-Way ANOVA incl. Bonferroni Post-Hoc test was performed to compare groups. Targeted compound synthesis, loading onto DEB, and intra-arterial administration were feasible and successful in all cases. Serum liver enzyme levels increased in a dose dependent manner within 24 h and normalized within 3 days for 0.2/0.6 mg/kg SW43-DOX-⁸⁹Y loaded onto DEB. The two rabbits treated with 1 mg/kg SW43-DOX-⁸⁹Y had to be euthanized after 3/24 h due to worsening general condition. Histopathological necrosis increased over time in a dose depended manner with 95-100% tumor necrosis 3-7 days post treatment (0.6 mg/kg). SW43-DOX-⁸⁹Y loaded onto DEB can be formulated and safely administered at a concentration of 0.6 mg/kg. Loading with radioactive isotopes (e.g., ⁸⁶yttrium/⁹⁰yttrium/¹⁷⁷lutetium) to synthesize the targeted radio-chemoembolization drug-eluting bead (TRCE-DEB) concept drug is feasible.

SW43-DOX ± loading onto drug-eluting bead, a potential new targeted drug delivery platform for systemic and locoregional cancer treatment - An in vitro evaluation

Treatment of unresectable primary cancer and their distant metastases, with the liver representing one of the most frequent location, is still plagued by insufficient treatment success and poor survival rates. The Sigma-2 receptor is preferentially expressed on many tumor cells making it an appealing target for therapy. Thus, we developed a potential targeted drug conjugate consisting of the Sigma-2 receptor ligand SW43 and Doxorubicin (SW43-DOX) for systemic cancer therapy and for locoregional treatment of primary and secondary liver malignancies when loaded onto drug-eluting bead (DEB) which was compared in vitro to the treatment with Doxorubicin alone. SW43-DOX binds specifically to the Sigma-2 receptor expressed on hepatocellular (Hep G2, Hep 3B), pancreatic (Panc-1) and colorectal (HT-29) carcinoma cell lines with high affinity and subsequent early specific internalization. Free SW43-DOX showed superior concentration and time depended cancer toxicity than treatment with Doxorubicin alone. Action mechanisms analysis revealed an apoptotic cell death with increased caspase 3/7 activation and reactive oxygen species (ROS) production. Only ROS scavenging with α-Tocopherol, but not the caspase inhibition (Z-VAD-FMK), partly reverted the effect. SW43-DOX could successfully be loaded onto DEB and showed prolonged eluting kinetics compared to Doxorubicin. SW43-DOX loaded DEB vs. Doxorubicin loaded DEB showed a significantly greater time dependent toxicity in all cell lines. In conclusion, the novel conjugate SW43-DOX ± loading onto DEB is a promising drug delivery platform for targeted systemic and locoregional cancer therapy.