In vivo isolated kidney perfusion with tumour necrosis factor α (TNF-α) in tumour-bearing rats

Isolated perfusion of the extremities with high-dose tumour necrosis factor α (TNF-α) plus melphalan leads to dramatic tumour response in patients with irresectable soft tissue sarcoma or multiple melanoma in transit metastases. We developed in vivo isolated organ perfusion models to determine whether similar tumour responses in solid organ tumours can be obtained with this regimen. Here, we describe the technique of isolated kidney perfusion. We studied the feasibility of a perfusion with TNF-α and assessed its anti-tumour effects in tumour models differing in tumour vasculature. The maximal tolerated dose (MTD) proved to be only 1 μg TNF-α. Higher doses appeared to induce renal failure and a secondary cytokine release with fatal respiratory and septic shock-like symptoms. In vitro, the combination of TNF-α and melphalan did not result in a synergistic growth-inhibiting effect on CC 531 colon adenocarcinoma cells, whereas an additive effect was observed on osteosarcoma ROS-1 cells. In vivo isolated kidney perfusion, with TNF-α alone or in combination with melphalan, did not result in a significant anti-tumour response in either tumour model in a subrenal capsule assay. We conclude that, because of the susceptibility of the kidney to perfusion with TNF-α, the minimal threshold concentration of TNF-α to exert its anti-tumour effects was not reached. The applicability of TNF-α in isolated kidney perfusion for human tumours seems, therefore, questionable. © 1999 Cancer Research Campaig

Activated CD4+ T cells enhance radiation effect through the cooperation of interferon-γ and TNF-α

<p>Abstract</p> <p>Background</p> <p>Approaches that enhance radiation effect may lead to improved clinical outcome and decrease toxicity. Here we investigated whether activated CD4+ T cells (aCD4) can serve as an effective radiosensitizer.</p> <p>Methods</p> <p>CD4+ T cells were activated with anti-CD3 and anti-CD28 mAbs. Hela cells were presensitized with aCD4 or conditioned supernatant (aCD4S) or recombinant cytokines for 2 days, followed γ-irradiation. The treated cells were cultured for an additional 2 to 5 days for cell proliferation, cell cycle, and western blot assays. For confirmation, other cancer cell lines were also used.</p> <p>Results</p> <p>Presensitization of tumor cells with aCD4 greatly increased tumor cell growth inhibition. Soluble factors secreted from activated CD4⁺T cells were primarily responsible for the observed effect. IFN-γ seemed to play a major role. TNF-α, though inactive by itself, significantly augmented the radiosensitizing activity of IFN-γ. aCD4S, but not IFN-γ or IFN-γ/TNF-α combination, was found to enhance the γ-irradiation-induced G2/M phase arrest. Bax expression was highly upregulated in Hela cells presensitized with aCD4S followed by γ-irradiation. The radio-sensitizing activity of aCD4 is not uniquely observed with Hela cell line, but also seen with other cancer cell lines of various histology.</p> <p>Conclusions</p> <p>Our findings suggest possible molecular and cellular mechanisms that may help explain the radio-sensitization effect of activated lymphocytes, and may provide an improved strategy in the treatment of cancer with radiotherapy.</p

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

Previously we demonstrated that addition of Tumour Necrosis Factor-α to melphalan or doxorubicin in a so-called isolated limb perfusion results in synergistic antitumour responses of sarcomas in both animal models and patients. Yet, 20 to 30% of the treated tumours do not respond. Therefore agents that synergise with tumour necrosis factor alpha must be investigated. Actinomycin D is used in combination with melphalan in isolated limb perfusion in the treatment of patients with melanoma in-transit metastases and is well known to augment tumour cell sensitivity towards tumour necrosis factor alpha in vitro. Both agents are very toxic, which limits their systemic use. Their applicability may therefore be tested in the isolated limb perfusion setting, by which the tumours can be exposed to high concentrations in the absence of systemic exposure. To study the beneficial effect of the combination in vivo, BN-175 soft tissue sarcoma-bearing rats were perfused with various concentrations of actinomycin D and tumour necrosis factor alpha. When used alone the drugs had only little effect on the tumour. Only when actinomycin D and tumour necrosis factor alpha were combined a tumour response was achieved. However, these responses were accompanied by severe, dose limiting, local toxicity such as destruction of the muscle tissue and massive oedema. Our results show that isolated limb perfusion with actinomycin D in combination with tumour necrosis factor alpha leads to a synergistic anti-tumour response but also to idiosyncratic locoregional toxicity to the normal tissues. Actinomycin D, in combination with tumour necrosis factor alpha, should not be explored in the clinical setting because of this. The standard approach in the clinic remains isolated limb perfusion with tumour necrosis factor alpha in combination with melphalan