SapC–DOPS as a Novel Therapeutic and Diagnostic Agent for Glioblastoma Therapy and Detection: Alternative to Old Drugs and Agents

Abstract

Glioblastoma multiforme (GBM), the most common type of brain cancer, is extremely aggressive and has a dreadful prognosis. GBM comprises 60% of adult brain tumors and the 5 year survival rate of GBM patients is only 4.3%. Standard-of-care treatment includes maximal surgical removal of the tumor in combination with radiation and temozolomide (TMZ) chemotherapy. TMZ is the “gold-standard” chemotherapy for patients suffering from GBM. However, the median survival is only about 12 to 18 months with this protocol. Consequently, there is a critical need to develop new therapeutic options for treatment of GBM. Nanomaterials have unique properties as multifunctional platforms for brain tumor therapy and diagnosis. As one of the nanomaterials, lipid-based nanocarriers are capable of delivering chemotherapeutics and imaging agents to tumor sites by enhancing the permeability of the compound through the blood–brain barrier, which makes them ideal for GBM therapy and imaging. Nanocarriers also can be used for delivery of radiosensitizers to the tumor to enhance the efficacy of the radiation therapy. Previously, high-atomic-number element-containing particles such as gold nanoparticles and liposomes have been used as radiosensitizers. SapC–DOPS, a protein-based liposomal drug comprising the lipid, dioleoylphosphatidylserine (DOPS), and the protein, saposin C (SapC), has been shown to be effective for treatment of a variety of cancers in small animals, including GBM. SapC–DOPS also has the unique ability to be used as a carrier for delivery of radiotheranostic agents for nuclear imaging and radiotherapeutic purposes. These unique properties make tumor-targeting proteo-liposome nanocarriers novel therapeutic and diagnostic alternatives to traditional chemotherapeutics and imaging agents. This article reviews various treatment modalities including nanolipid-based delivery and therapeutic systems used in preclinical and clinical trial settings for GBM treatment and detection.

Evolving Diagnostic and Treatment Strategies for Pediatric CNS Tumors: The Impact of Lipid Metabolism

“…On the other hand, BXQ-350 (SapC-DOPS) is a nanosome composed of the lysosomal protein saposin C (SapC) and dioleoylphosphatidylserine (DOPS) that targets the surface PS exposed by cancer cells and ceramide-enriched membranes. It is then internalized by endocytosis and induces cell death (necrosis, apoptosis and autophagy) through lysosome activation [193,194]. In addition, the treatment of cancer cells with BXQ-350 sensitizes the cells to irradiation [195].…”