Forest Valérie, Peoc'h Michel, Campos Lydia, Guyotat Denis, Vergnon Jean-Michel
UPRES-EA3063, Faculté de Médecine Jacques Lisfranc, 15 rue Ambroise Paré, 42023 Saint-Etienne cedex 2, France.
Cryobiology. 2005 Feb;50(1):29-37. doi: 10.1016/j.cryobiol.2004.09.007.
Lung cancers are among the most frequent and the most lethal tumours. They are mainly treated by surgery or by chemotherapy, but in the most advanced stages a local cryotherapy can be proposed as a palliative option for bronchial clearance. This therapy, based on the cytotoxic effects of low temperatures, acts by mechanisms which are not yet totally understood. The aim of this work was to investigate in vivo the biological effects of cryotherapy in a model of human non-small-cell lung cancer. We used a xenograft system: cells from the A549 cell line (adenocarcinoma) were injected subcutaneously into SCID mice. Cryotherapy was performed (three cycles, nitrous oxide cryoprobe). Chemotherapy (intravenous injection of Vinorelbine (Navelbine), 4.8 mg/kg) was used as a control treatment. Tumour nodes were excised at variable time points and studied morphologically. The induction of apoptosis was analysed by immunohistochemical staining of cleaved caspase-3 and by TUNEL. Results showed that cryotherapy was an efficient technique to induce cell death either by necrosis or by apoptosis. Necrosis was found near the cryoprobe impact site and was maximal 2 h after treatment (65%); a second peak was observed after 4 days (77%). Around this central necrotic area, apoptotic cells were found. Apoptosis was maximal after 8 h (47%). Chemotherapy induced apoptosis in a fewer number of cells and this effect was not time-dependent. Taken together, these results demonstrate the differential effects of cryotherapy and chemotherapy in vivo, suggesting different modes of action and the potential benefit to combine them.
肺癌是最常见且致死率最高的肿瘤之一。其主要治疗方式为手术或化疗，但在疾病最晚期，局部冷冻疗法可作为支气管清理的姑息治疗选择。这种基于低温细胞毒性作用的疗法，其作用机制尚未完全明确。本研究旨在通过人非小细胞肺癌模型，在体内探究冷冻疗法的生物学效应。我们采用了异种移植系统：将A549细胞系（腺癌）的细胞皮下注射到SCID小鼠体内。进行冷冻疗法（三个周期，一氧化二氮冷冻探头）。化疗（静脉注射长春瑞滨（诺维本），4.8毫克/千克）用作对照治疗。在不同时间点切除肿瘤结节并进行形态学研究。通过裂解的半胱天冬酶-3免疫组化染色和TUNEL法分析细胞凋亡的诱导情况。结果表明，冷冻疗法是一种通过坏死或凋亡诱导细胞死亡的有效技术。在冷冻探头作用部位附近发现坏死，治疗后2小时坏死程度最高（65%）；4天后观察到第二个峰值（77%）。在这个中央坏死区域周围发现凋亡细胞。凋亡在8小时后达到最大值（47%）。化疗诱导凋亡的细胞数量较少，且这种效应不具有时间依赖性。综上所述，这些结果证明了冷冻疗法和化疗在体内的不同效应，提示了不同的作用方式以及联合应用它们的潜在益处。
