Treatment of Hepatocellular Carcinoma by Intratumoral Injection of 125I-AA98 mAb and Its Efficacy Assessments by Molecular Imaging

CD146-targeted nuclear medicine imaging in cancer: state of the art

The transmembrane glycoprotein adhesion molecule CD146 is overexpressed in a wide variety of cancers. Through molecular imaging, a specific biomarker's expression and distribution can be viewed in vivo non-invasively. Radionuclide-labeled monoclonal antibodies or relevant fragments that target CD146 may find potential applications in cancer imaging, thereby offering tremendous value in cancer diagnosis, staging, prognosis evaluation, and prediction of drug resistance. This review discusses the recent developments of CD146-targeted molecular imaging via nuclear medicine, especially in malignant melanoma, brain tumor, lung cancer, liver cancer, breast cancer, and pancreatic cancer. Many studies have proved that CD146 targeting may present a promising strategy for cancer theranostics.

Evaluation of the pharmacokinetics, dosimetry, and therapeutic efficacy for the α-particle-emitting transarterial radioembolization (αTARE) agent [225Ac]Ac-DOTA-TDA-Lipiodol® against hepatic tumors

BACKGROUND

The liver is a common site for metastatic disease for a variety of cancers, including colorectal cancer. Both primary and secondary liver tumors are supplied through the hepatic artery while the healthy liver is supplied by the portal vein. Transarterial radioembolization (TARE) using yttrium-90 glass or resin microspheres have shown promising results with reduced side-effects but have similar survival benefits as chemoembolization in patients with hepatocellular carcinoma (HCC). This highlights the need for new novel agents against HCC. Targeted alpha therapy (TAT) is highly potent treatment due to the short range (sparing adjacent normal tissue), and densely ionizing track (high linear energy transfer) of the emitted α-particles. The incorporation of α-particle-emitting radioisotopes into treatment of HCC has been extremely limited, with our recent publication pioneering the field of α-particle-emitting TARE (αTARE). This study focuses on an in-depth evaluation of the αTARE-agent [225Ac]Ac-DOTA-TDA-Lipiodol® as an effective therapeutic agent against HCC regarding pharmacokinetics, dosimetry, stability, and therapeutic efficacy.

RESULTS

[225Ac]Ac-DOTA-TDA was shown to be a highly stable with bench-top stability at ≥ 95% radiochemical purity (RCP) over a 3-day period and serum stability was ≥ 90% RCP over 5-days. The pharmacokinetic data showed retention in the tumor of [225Ac]Ac-DOTA-TDA-Lipiodol® and clearance through the normal organs. In addition, the tumor and liver acted as suppliers of the free daughters, which accumulated in the kidneys supplied via the blood. The dose limiting organ was the liver, and the estimated maximum tolerable activity based on the rodents whole-body weight: 728-3641 Bq/g (male rat), 396-1982 Bq/g (male mouse), and 453-2263 Bq/g (female mouse), depending on an RBE-value (range 1-5). Furthermore, [225Ac]Ac-DOTA-TDA-Lipiodol® showed significant improvement in survival for both the male and female mice (median survival 47-days) compared with controls (26-days untreated, and 33-35-days Lipiodol® alone).

CONCLUSIONS

This study shows that [225Ac]Ac-DOTA-TDA-Lipiodol® is a stable compound allowing for centralized manufacturing and distribution world-wide. Furthermore, the result of this study support the continue development of evaluation of the αTARE-agent [225Ac]Ac-DOTA-TDA-Lipiodol® as a potential treatment option for treating hepatic tumors.

Novel antigens for targeted radioimmunotherapy in hepatocellular carcinoma

Liver cancer is the sixth common cancer and forth cause of cancer-related death worldwide. Based on usually advanced stages of hepatocellular carcinoma (HCC) at the time of diagnosis, therapeutic options are limited and, in many cases, not effective, and typically result in the tumor recurrence with a poor prognosis. Radioimmunotherapy (RIT) offers a selective internal radiation therapy approach using beta or alpha emitting radionuclides conjugated with tumor-specific monoclonal antibodies (mAbs), or specific selective peptides. When compared to chemotherapy or radiotherapy, radiolabeled mAbs against cancer-associated antigens could provide a high therapeutic and exclusive radiation dose for cancerous cells while decreasing the exposure-induced side effects to healthy tissues. The recent advances in cancer immunotherapy, such as blockade of immune-checkpoint inhibitors (ICIs), has changed the landscape of cancer therapy, and the efficacy of different classes of immunotherapy has been tested in many clinical trials. Taking into account the use of ICIs in the liver tumor microenvironment, combined therapies with different approaches may enhance the outcome in the future clinical studies. With the development of novel immunotherapy treatment options in the recent years, there has been a great deal of information about combining the diverse treatment modalities to boost the effectiveness of immunomodulatory drugs. In this opinion review, we will discuss the recent advancements in RIT. The current status of immunotherapy and internal radiotherapy will be updated, and we will propose novel approaches for the combination of both techniques. Potential target antigens for radioimmunotherapy in Hepatocellular carcinoma (HCC). HCC radioimmunotherapy target antigens are the most specific and commonly accessible antigens on the surface of HCC cells. CTLA-4 ligand and receptor, TAMs, PD-1/PD-L, TIM-3, specific IEXs/TEXs, ROBO1, and cluster of differentiation antigens CD105, CD147 could all be used in HCC radioimmunotherapy. Abbreviations: TAMs, tumor-associated macrophages; CTLA-4, cytotoxic T-lymphocyte associated antigen-4; PD-1, Programmed cell death protein 1; PD-L, programmed death-ligand1; TIM-3, T-cell immunoglobulin (Ig) and mucin-domain containing protein-3; IEXs, immune cell-derived exosomes; TEXs, tumor-derived exosomes.

Development of Duramycin-Based Molecular Probes for Cell Death Imaging

Cell death is involved in numerous pathological conditions such as cardiovascular disorders, ischemic stroke and organ transplant rejection, and plays a critical role in the treatment of cancer. Cell death imaging can serve as a noninvasive means to detect the severity of tissue damage, monitor the progression of diseases, and evaluate the effectiveness of treatments, which help to provide prognostic information and guide the formulation of individualized treatment plans. The high abundance of phosphatidylethanolamine (PE), which is predominantly confined to the inner leaflet of the lipid bilayer membrane in healthy mammalian cells, becomes exposed on the cell surface in the early stages of apoptosis or accessible to the extracellular milieu when the cell suffers from necrosis, thus representing an attractive target for cell death imaging. Duramycin is a tetracyclic polypeptide that contains 19 amino acids and can bind to PE with excellent affinity and specificity. Additionally, this peptide has several favorable structural traits including relatively low molecular weight, stability to enzymatic hydrolysis, and ease of conjugation and labeling. All these highlight the potential of duramycin as a candidate ligand for developing PE-specific molecular probes. By far, a couple of duramycin-based molecular probes such as Tc-99 m-, F-18-, or Ga-68-labeled duramycin have been developed to target exposed PE for in vivo noninvasive imaging of cell death in different animal models. In this review article, we describe the state of the art with respect to in vivo imaging of cell death using duramycin-based molecular probes, as validated by immunohistopathology.

MCAM is associated with metastasis and poor prognosis in osteosarcoma by modulating tumor cell migration

Background

Although there are standard treatment options for osteosarcoma (OS), the prognoses of patients with OS remain varied. Therefore, it is important to profile OS patients at a high risk of mortality to develop focused interventions. Although tumor biomarkers are closely associated with clinical outcomes, data on prognostic biomarkers for OS remain scarce.

Methods

We collected RNA expression profiles and clinical data of 90 OS patients from the GEO database (dataset GSE21257 and GSE39055) and 96 patients in the TARGET program. The data were analyzed using univariate Kaplan‐Meier survival analysis to screen candidate gene sets that might be associated with OS survival.

Results

Our analysis demonstrated that melanoma cell adhesion molecule (MCAM) was associated with overall survival of patients with OS in the three cohorts. The data showed that MCAM was upregulated in OS patients who had metastases within 5 years compared to those without metastases. GO analysis revealed that genes correlated with MCAM were mainly involved in cell migration and wound healing processes. In addition, wound healing assays and gene set enrichment analysis results from RNA sequencing data of small interfering (si)‐MCAM‐transfected OS cells demonstrated that MCAM modulated tumor cell migration.

Conclusions

Our data demonstrate that MCAM may be a novel prognostic biomarker for OS. MCAM is associated with increased cell migration ability and risk of metastasis, thus leading to poor prognoses in OS patients.

Potential of peptide-engineered exosomes with overexpressed miR-92b-3p in anti-angiogenic therapy of ovarian cancer

INTRODUCTION

Exosomal microRNA (miRNA) as a mediator of intercellular communication plays an essential part in tumor-relevant angiogenesis. Therapy against angiogenesis has been demonstrated to have a remarkable antitumor efficacy in various malignancies, but not as expected in ovarian cancer.

METHODS

Exosomes were isolated by ultracentrifugation. Exosomal miRNA sequencing and gene function experiments were used to identify the differential expressed miRNAs in exosomes and their mRNA targets. SKOV3 cell line that stably overexpressed miR-92b-3p was constructed by lentivirus. In vitro, angiogenesis was analyzed by tube formation assay and migration assay. The angiogenic and antitumor effects in vivo were assessed in zebrafish and nude mouse models. Combination index was calculated to assess the synergetic inhibition of angiogenesis between miR-92b-3p and Apatinib. Peptides were conjugated with exosomal membranes to obtain engineered exosomes.

RESULTS

Ovarian cancer cell-derived exosomes facilitated the angiogenesis and migration capability of vascular endothelial cells in vitro and in vivo. The expression of miR-92b-3p was much lower in ovarian cancer cell-derived exosomes than that in immortalized ovarian epithelial cell-derived exosomes. The exosomal miR-92b-3p modulated tumor-associated angiogenesis via targeting SOX4. Besides, Peptide-engineered exosomes with overexpressed miR-92b-3p showed the stronger abilities of anti-angiogenesis and antitumor than parental exosomes, whether alone or combined with Apatinib.

CONCLUSIONS

Our findings demonstrate the effect and mechanism of exosomal miR-92b-3p from ovarian cancer cells on tumor-associated angiogenesis and the potential of artificially generated exosomes with overexpressed miR-92b-3p to be used as anti-angiogenic agent, which may provide a new approach for anti-angiogenic therapy of ovarian cancer.

Antitumor Effects of Curcumin and Glycyrrhetinic Acid-Modified Curcumin-Loaded Cationic Liposome by Intratumoral Administration

Curcumin is a hydrophobic polyphenolic compound extracted from the rhizome of Curcuma longa and shows a line of active biological functions, but its application has been limited and questioned because of its low solubility, low bioavailability, and rapid metabolism. In terms of antitumor effect, these disadvantages can be overcome by intratumoral injection. In this study, we present the intratumoral injection of curcumin and glycyrrhetinic acid-modified curcumin-loaded cationic liposome (GAMCLCL) in H22 tumor-bearing mice. The experimental results demonstrated that curcumin exhibited positive antitumor activities in vitro and in vivo by intratumoral injection, but its activities were much weaker than GAMCLCL and adriamycin. Compared with free curcumin, GAMCLCL showed much better effects in improving the blood parameters (WBC, RBC, PLT, ALT, CRE, and LDH), inhibiting tumor growth, reducing tumor microvascular density, downregulating the expression of VEGF-protein and mRNA, and upregulating the expression of caspase-3 protein and mRNA in H22 tumor tissues. Under the experimental conditions of this study, the antitumor effect of high-dose GAMCLCL was similar to adriamycin. In conclusion, the experimental results demonstrated that free curcumin possessed definite antitumor efficacy, but its antitumor activities were weaker, and some strategies should be adopted to overcome its disadvantages, improve, and ensure its clinical efficacy.