Neutrophil Influx and Chemokine Production during the Early Phases of the Antitumor Response to the Vascular Disrupting Agent DMXAA (ASA404)

Abstract

5,6-Dimethylxanthenone-4-acetic acid (DMXAA) acts through tumor vascular disruption and cytokine production and is the first of its class to enter phase 3 trials. We characterized leukocytes and cytokines in murine Colon 38 tumors before and after DMXAA treatment. Tumor mass declined 50% 24 hours after DMXAA administration, but the leukocyte count per gram of tumor increased threefold owing to a large influx of Ly6G(+)CD11b(+)F4/80(-) cells with the morphology of neutrophils. However, B and T lymphocytes, natural killer cells, and macrophages in the tumor all decreased in numbers. Seven chemokines were substantially induced in the tumor, spleen, and serum 4 hours after DMXAA administration. Using cultured spleen cell subpopulations, CD11b(+) cells (largely monocytes and macrophages) were shown to be the primary producers of tumor necrosis factor alpha, interleukin 6 (IL-6), and macrophage inflammatory 1alpha (MIP-1alpha). CD49b(+) natural killer cells produced IP-10, whereas CD45R(+) B lymphocytes produced regulated upon activation normal T cell express sequence. T lymphocytes were not major producers of cytokines in the response to DMXAA. Murine peripheral blood leukocytes (PBLs) produced a similar panel of cytokines in culture to that detected in mouse serum after DMXAA treatment. Cytokines in human PBL cultures were subsequently measured with the aim of identifying potential serum markers of the human response to DMXAA. IP-10 (P < .001), monocyte chemoattractant protein 1 (P < .001), and sCD40L (P < .01) were decreased, whereas IL-8 (P < .001) and MIP-1alpha (P = .03) were increased in DMXAA-treated compared with untreated PBL cultures from a group of 12 donors.

Influence of the vascular damaging agents DMXAA and ZD6126 on hypericin distribution and accumulation in RIF-1 tumors

“…Based on our findings, we suggest that hypericin is partially cleared from necrotic tissue by uptake in polymorphonuclear neutrophils, and it seems unlikely that this phenomenon makes up part of an immunologically concerted mechanism. Furthermore, this theory is in line with previous findings that neutrophil levels in subcutaneously implanted Colon 38 tumors are increased shortly after DMXAA treatment (Wang et al 2009). …”

Vascular priming enhances chemotherapeutic efficacy against head and neck cancer

“…The results (shown in Supplementary Fig. 6 ) were consistent with DMXAA exerting its antivascular activity through cytokine induction and chemokine modulation, including induction of tumor necrosis factor (TNF-alpha) and interleukin (IL-6) canonical pathways (28-30). Analysis of the functional interactions between gene classes in the transcriptomes under study with Gene Ontology identified several annotated biomarkers including IL-8, MMP-10, STAT1, STC1, FSTL3, CXCL1 and CTSB.…”

The unique characteristics of tumor vasculature and preclinical evidence for its selective disruption by Tumor-Vascular Disrupting Agents

“…This effect has been detected within 30 minutes of administration in animal models (Figure 5). 80,81 A large and early influx of neutrophils into subcutaneous Colon 38 tumors occurs following ASA404 treatment, and neutrophils have therefore been suggested as mediators of the drug’s rapid anti-vascular effects 82. Activated neutrophils are strongly implicated in endothelial cell damage and killing during inflammation 83.…”