Intraperitoneal mitomycin C improves survival compared to cytoreductive surgery alone in an experimental model of high-grade pseudomyxoma peritonei

Appendiceal tumors and pseudomyxoma peritonei: French Intergroup Clinical Practice Guidelines for diagnosis, treatments and follow-up (RENAPE, RENAPATH, SNFGE, FFCD, GERCOR, UNICANCER, SFCD, SFED, SFRO, ACHBT, SFR)

INTRODUCTION

This document is a summary of the French Intergroup guidelines regarding the management of appendicular epithelial tumors (AT) and pseudomyxoma peritonei (PMP) published in March 2020, available on the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org).

METHODS

All French medical societies specialized in the management of AT and PMP collaboratively established these recommendations based on literature until December 2019 and the results of a Delphi vote carried out by the Peritoneal Surface Oncology Group International experts, and graded into 4 categories (A, B, C, Expert Agreement) according to their level of evidence.

RESULTS

AT and PMP are rare but represent a wide range of clinico-pathological entities with several pathological classification systems and different biological behaviors. Their treatment modalities may vary accordingly and range from simple surveillance or laparoscopic appendectomy to complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) and / or systemic chemotherapy. The prognosis of these neoplasms may also largely vary according to their pathological grade and spreading at diagnosis or during the follow-up. Given the rarity of certain situations, the therapeutic strategy adapted to each patient, must be discussed in a specialized multidisciplinary meeting after a specialized pathological and radiological pre-therapeutic assessment and a clinical examination by a surgeon specializing in the management of rare peritoneal malignancies.

CONCLUSION

These recommendations are proposed to achieve the most beneficial strategy in a daily practice as the wide range and the rareness of these entities renders their management challenging. These guidelines are permanently being reviewed.

Preclinical In Vivo-Models to Investigate HIPEC; Current Methodologies and Challenges

Simple Summary

Efficacy of cytoreductive surgery (CRS) combined with hyperthermic intraperitoneal chemotherapy (HIPEC) depends on patient selection, tumor type, delivery technique, and treatment parameters such as temperature, carrier solution, type of drug, dosage, volume, and treatment duration. Preclinical research offers a powerful tool to investigate the impact of these parameters and to assists in designing potentially more effective treatment protocols and clinical trials. This study aims to review the objectives, methods, and clinical relevance of in vivo preclinical HIPEC studies found in the literature. In total, 60 articles were included in this study. The selected articles were screened on the HIPEC parameters. Recommendations are provided and possible pitfalls are discussed on the choice of type of animal and tumor model per stratified parameters and study goal. The guidelines presented in this paper can improve the clinical relevance and impact of future in vivo HIPEC experiments.

Abstract

Hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment modality for patients with peritoneal metastasis (PM) of various origins which aims for cure in combination with cytoreductive surgery (CRS). Efficacy of CRS-HIPEC depends on patient selection, tumor type, delivery technique, and treatment parameters such as temperature, carrier solution, type of drug, dosage, volume, and treatment duration. Preclinical research offers a powerful tool to investigate the impact of these parameters and to assist in designing potentially more effective treatment protocols and clinical trials. The different methodologies for peritoneal disease and HIPEC are variable. This study aims to review the objectives, methods, and clinical relevance of in vivo preclinical HIPEC studies found in the literature. In this review, recommendations are provided and possible pitfalls are discussed on the choice of type of animal and tumor model per stratified parameters and study goal. The guidelines presented in this paper can improve the clinical relevance and impact of future in vivo HIPEC experiments.

Synthesis of benzoxazole-based vorinostat analogs and their antiproliferative activity

Hydroxamic acid derivatives constitute an interesting novel class of antitumor agents. Three of them, including vorinostat, are approved drugs for the treatment of malignancies, while several others are currently under clinical trials. In this work, we present new vorinostat analogs containing the benzoxazole ring as the cap group and various linkers. The benzoxazole-based analogs were synthesized starting either from 2-aminobenzoxazole, through conventional coupling, or from benzoxazole, through a metal-free oxidative amination. All the synthesized compounds were evaluated for their antiproliferative activity on three diverse human cancer cell lines (A549, Caco-2 and SF268), in comparison to vorinostat. Compound 12 (GK601), carrying a benzoxazole ring replacement for the phenyl ring of vorinostat, was the most potent inhibitor of the growth of three cell lines (IC₅₀ 1.2-2.1 μΜ), similar in potency to vorinostat. Compound 12 also inhibited human HDAC1, HDAC2 and HDAC6 like vorinostat. This new analog also showed antiproliferative activity against two colon cancer cell lines genetically resembling pseudomyxoma peritonei (PMP), namely HCT116 GNAS R201C/+ and LS174T (IC₅₀ 0.6 and 1.4 μΜ, respectively) with potency comparable to vorinostat (IC₅₀ 1.1 and 2.1 μΜ, respectively).

The Temperature-Dependent Effectiveness of Platinum-Based Drugs Mitomycin-C and 5-FU during Hyperthermic Intraperitoneal Chemotherapy (HIPEC) in Colorectal Cancer Cell Lines

Cytoreductive surgery (CRS) followed by hyperthermic intraperitoneal chemotherapy (HIPEC) is a treatment with curative intent for peritoneal metastasis of colorectal cancer (CRC). Currently, there is no standardized HIPEC protocol: choice of drug, perfusate temperature, and duration of treatment vary per institute. We investigated the temperature-dependent effectiveness of drugs often used in HIPEC.

METHODS

The effect of temperature on drug uptake, DNA damage, apoptosis, cell cycle distribution, and cell growth were assessed using the temperature-dependent IC50 and Thermal Enhancement Ratio (TER) values of the chemotherapeutic drugs cisplatin, oxaliplatin, carboplatin, mitomycin-C (MMC), and 5-fluorouracil (5-FU) on 2D and 3D CRC cell cultures at clinically relevant hyperthermic conditions (38-43 °C/60 min).

RESULTS

Hyperthermia alone decreased cell viability and clonogenicity of all cell lines. Treatment with platinum-based drugs and MMC resulted in G2-arrest. Platinum-based drugs display a temperature-dependent synergy with heat, with increased drug uptake, DNA damage, and apoptosis at elevated temperatures. Apoptotic levels increased after treatment with MMC or 5-FU, without a synergy with heat.

CONCLUSION

Our in vitro results demonstrate that a 60-min exposure of platinum-based drugs and MMC are effective in treating 2D and 3D CRC cell cultures, where platinum-based drugs require hyperthermia (>41 °C) to augment effectivity, suggesting that they are, in principle, suitable for HIPEC.