Intratumoral Visualization of Oxaliplatin within a Liposomal Formulation Using X-ray Fluorescence Spectrometry

Design, synthesis and evaluation of diarylidenyl piperidone-ligated platinum (IV) complexes as chemoimmunotherapeutic agents

A set of diarylidenyl piperidone-ligated platinum (IV) complexes 8a‒8d with chemoimmunotherapy effects was designed and synthesized based on introduction of classic STAT3 inhibitors, diarylidenyl piperidones, into an oxaliplatin (OXA)-based skeleton. 3-(4,5)-Dimethylthiahiazo (-z-y1)-3, 5-di- phenytetrazoliumromide (MTT) assay indicated that complexes 8a‒8d exhibited obvious inhibition on T24, MDA-MB-231 and SW480 cell lines compared to OXA, with IC50 values in range of 4.96 ± 0.14-21.1 ± 0.35 μM. SW480 xenograft nude mice assay demonstrated that complexes 8a (2 mg/kg and 4 mg/kg), 8b (4 mg/kg) and 8c (4 mg/kg) exhibited effective inhibition on this model with tumor inhibitory rates (TIR) of 46.06 %, 51.18 %, 48.82 % and 42.16 %, respectively, compared with OXA (2 mg/kg, TIR = 31.89 %/34.31 %) during 21-days treatment, while CT-26 xenograft BALB/C mice assay showed that complexes 8a (10 mg/kg), 8b (5 and 10 mg/kg), 8c (5 and 10 mg/kg), and 8d (5 and 10 mg/kg) exhibited effective inhibition of with TIR values of 56.95 %, 56.28 %, 78.02 %, 47.28 %, 63.80 %, 51.90 % and 70.65 %, respectively, compared with OXA (5 mg/kg, TIR = 69.28 %/67.53 %) during 13-days treatment. The pathology results in SW480 and CT-26 xenograft showed that complexes 8a-8d displayed limited toxicity in comparison with OXA. All these results indicated that complexes 8a-8c may be good chemoimmunotherapeutic agents with potent efficacy and safety profiles. Further mechanistic studies revealed that the representative complex 8b might exert its chemoimmunotherapeutic effect by inhibiting the expression and phosphorylation of STAT3, thus evoking CD4+ and CD8+ T lymphocyte immune responses and inducing ferroptosis and apoptosis.

Nanocarrier System for Increasing the Therapeutic Efficacy of Oxaliplatin

The application of Oxaliplatin (OxPt) in different malignancies is reported to be accompanied by several side effects including neuropathy, nausea, vomiting, diarrhea, mouth sores, low blood counts, loss of appetite, etc. The passive or active targeting of different tumors can improve OxPt delivery. Considering the demand for novel systems meant to improve the OxPt efficacy and define the shortcomings, we provided an overview of different approaches regarding the delivery of OxPt. There is an extending body of data that exhibits the value of Liposomes and polymer-based drug delivery systems as the most successful systems among the OxPt drug delivery procedures. Several clinical trials have been carried out to investigate the side effects and dose-limiting toxicity of liposomal oxaliplatin such as the assessment on Safety Study of MBP-426 (Liposomal Oxaliplatin Suspension for Injection) to Treat Advanced or Metastatic Solid Tumors. In addition, several studies indicated the biocompatibility and biodegradability of this product, as well as its option for being fictionalized to derive specialized smart nanosystems for the treatment of cancer. The better delivery of OxPt with weaker side effects could be generated by the exertion of Oxaliplatin, which involves the aggregation of new particles and multifaceted nanocarriers to compose a nanocomposite with both inorganic and organic nanoparticles.

[Elucidation for Intratumor Localization of a DDS-based Anticancer Drug and Enhancement of Its Therapeutic Effects via Improvement of the Tumor Microenvironment]

In the development of drug delivery system (DDS)-based anticancer drugs, the techniques for the intratumor mapping and quantification of active pharmaceutical ingredients (API) in pharmaceuticals must be pivotal for predicting pharmacological effects and adverse events. X-ray fluorescence spectrometry (XRF) is a potent analytical tool for mapping/quantifying platinum pharmaceutics such as oxaliplatin (l-OHP) and its liposomal formulation. In recent studies, we employed XRF to visualize the intratumor micro-distribution of l-OHP in a tumor-bearing model mouse intravenously injected with either free l-OHP or l-OHP liposomes. The intratumor distribution of l-OHP within tumor sections could be determined by XRF to detect platinum atoms. After treatment with the liposomal formulation, the l-OHP was localized near the tumor vessels and, via repeated injections, increasingly accumulated in tumors by a much greater degree than treatment with free l-OHP. The repeated injections of l-OHP liposomes improved the vascular permeability via inducing the apoptosis of tumor cells near the tumor vessels, which should improve the tumor microenvironment and enhance the intratumor accumulation of repeated doses of l-OHP liposomes. The proposed process was also used to visualize the intratumor distribution of l-OHP in rectal cancer specimens resected from a patient who had received l-OHP-based preoperative chemotherapy. We further revealed that neutralization of an acidic tumor microenvironment via oral administration with NaHCO₃ could improve the therapeutic efficacy of weakly basic anticancer agent-encapsulating liposomes. Collectively, mapping/quantifying the intratumor API in DDS drugs and/or improving the tumor microenvironment would be an effective means to accelerate the clinical development of DDS-based anticancer drugs.

X-ray-Based Techniques to Study the Nano-Bio Interface

X-ray-based analytics are routinely applied in many fields, including physics, chemistry, materials science, and engineering. The full potential of such techniques in the life sciences and medicine, however, has not yet been fully exploited. We highlight current and upcoming advances in this direction. We describe different X-ray-based methodologies (including those performed at synchrotron light sources and X-ray free-electron lasers) and their potentials for application to investigate the nano-bio interface. The discussion is predominantly guided by asking how such methods could better help to understand and to improve nanoparticle-based drug delivery, though the concepts also apply to nano-bio interactions in general. We discuss current limitations and how they might be overcome, particularly for future use in vivo.

Interventional Radiology for Local Immunotherapy in Oncology

Human intratumoral immunotherapy (HIT-IT) is under rapid development, with promising preliminary results and high expectations for current phase III trials. While outcomes remain paramount for patients and the referring oncologists, the technical aspects of drug injection are critical to the interventional radiologist to ensure optimal and reproducible outcomes. The technical considerations for HIT-IT affect the safety, efficacy, and further development of this treatment option. Image-guided access to the tumor allows the therapeutic index of a treatment to be enhanced by increasing the intratumoral drug concentration while minimizing its systemic exposure and associated on-target off-tumor adverse events. Direct access to the tumor also enables the acquisition of cancer tissue for sequential sampling to better understand the pharmacodynamics of the injected immunotherapy and its efficacy through correlation of immune responses, pathologic responses, and imaging tumor response. The aim of this article is to share the technical insights of HIT-IT, with particular consideration for patient selection, lesion assessment, image guidance, and technical injection options. In addition, the organization of a standard patient workflow is discussed, so as to optimize HIT-IT outcome and the patient experience.

Starting the fight in the tumor: expert recommendations for the development of human intratumoral immunotherapy (HIT-IT)

A European Society for Medical Oncology (ESMO)-sponsored expert meeting was held in Paris on 8 March 2018 which comprised 11 experts from academia, 11 experts from the pharmaceutical industry and 2 clinicians who were representatives of ESMO. The focus of the meeting was exclusively on the intratumoral injection/delivery of immunostimulatory agents with the aim of harmonizing the standard terms and methodologies used in the reporting of human intratumoral immunotherapy (HIT-IT) clinical trials to ensure quality assurance and avoid a blurring of the data reported from different studies. The goal was to provide a reference document, endorsed by the panel members that could provide guidance to clinical investigators, pharmaceutical companies, ethics committees, independent review boards, patient advocates and the regulatory authorities and promote an increase in the number and quality of HIT-IT clinical trials in the future. Particular emphasis was placed not only on the development of precise definitions to facilitate a better understanding between investigators but also on the importance of systematic serial biopsies as a driver for translational research and the need for the recording and reporting of data, to facilitate a better understanding of the key processes involved.