TNF- α augments intratumoural concentrations of doxorubicin in TNF- α -based isolated limb perfusion in rat sarcoma models and enhances anti-tumour effects

Abstract

We have shown previously that isolated limb perfusion (ILP) in sarcoma-bearing rats results in high response rates when melphalan is used in combination with tumour necrosis factor alpha (TNF-α). This is in line with observations in patients. Here we show that ILP with doxorubicin in combination with TNF-α has comparable effects in two different rat sarcoma tumour models. The addition of TNF-α exhibits a synergistic anti-tumour effect, resulting in regression of the tumour in 54% and 100% of the cases for the BN175-fibrosarcoma and the ROS-1 osteosarcoma respectively. The combination is shown to be mandatory for optimal tumour response. The effect of high dose TNF-α on the activity of cytotoxic agents in ILP is still unclear. We investigated possible modes by which TNF-α could modulate the activity of doxorubicin. In both tumour models increased accumulation of doxorubicin in tumour tissue was found: 3.1-fold in the BN175 and 1.8-fold in the ROS-1 sarcoma after ILP with doxorubicin combined with TNF-α in comparison with an ILP with doxorubicin alone. This increase in local drug concentration may explain the synergistic anti-tumour responses after ILP with the combination. In vitro TNF-α fails to augment drug uptake in tumour cells or to increase cytotoxicity of the drug. These findings make it unlikely that TNF-α directly modulates the activity of doxorubicin in vivo. As TNF-α by itself has no or only minimal effect on tumour growth, an increase in local concentrations of chemotherapeutic drugs might well be the main mechanism for the synergistic anti-tumour effects. © 2000 Cancer Research Campaign

Isolated limb perfusion with actinomycin D and TNF-alpha results in improved tumour response in soft-tissue sarcoma-bearing rats but is accompanied by severe local toxicity

“…These results correlate with in vitro studies using melphalan or doxorubicin in combination with TNF on several rat tumour cell lines as colon carcinomas and osteosarcomas (van Der Veen et al, 2001). However, in vivo combination of melphalan as well as doxorubicin with TNF did result in strong synergy both in patients and animal models (Lejeune et al, 1995;Eggermont et al, 1996bEggermont et al, ,c, 1997Eggermont et al, , 1999Manusama et al, 1996;Di Filippo et al, 1999;Van Der Veen et al, 2000). We speculated that this is due to the dual targeting of the combination.…”

“…We speculated that this is due to the dual targeting of the combination. Whereas the cytotoxic drugs preferentially target tumour cells, TNF mainly affects the tumour associated vasculature, possibly resulting in destruction of the vessels and augmented accumulation of the drugs in the tumour tissue (Eggermont et al, 1997;de Wilt et al, 2000c;ten Hagen et al, 2000;Van Der Veen et al, 2000). In the present study an isolated limb perfusion with TNF, actinomycin D or a combination in BN-175 soft tissue sarcoma bearing rats was performed to investigate the tumour response to these treatments.…”

“…We developed a rat tumour model and showed that results comparable to the clinic can be obtained regarding response rate and type of response (Manusama et al, 1996;de Wilt et al, 1999;Van Der Veen et al, 2000). We used this model to evaluate other drug combinations to improve tumour responses or to diminish toxic side effects.…”

“…However, ILP with doxorubicin in combination with TNF appeared less effective than melphalan with TNF. Response rates were respectively 54 and 70% (de Wilt et al, 1999;Van Der Veen et al, 2000).…”

Degree of tumour vascularity correlates with drug accumulation and tumour response upon TNF-α-based isolated hepatic perfusion

“…Moreover, angiographic studies performed in patients pre-and post-TNF-a perfusion showed selective destruction of tumour-associated vasculature and histologic studies demonstrated haemorrhagic necrosis of the tumour (Olieman et al, 1997). Recently, we demonstrated, what we consider a key explanation for the potent synergy between TNF-a and chemotherapy, an up to six-fold increased intratumoural melphalan or doxorubicin concentration in rat sarcomas after ILP when highdose TNF-a was coadministrated van der Veen et al, 2000). These findings led to the hypothesis that TNF-a causes specific destruction of tumour endothelial cells and thereby induces an increased permeability of tumour vasculature.…”