Marinelli Sara, Salvatore Veronica, Baron Toaldo Marco, Milazzo Maddalena, Croci Luca, Venerandi Laura, Pecorelli Anna, Palamà Chiara, Diana Alessia, Bolondi Luigi, Piscaglia Fabio
Department of Medical and Surgical Sciences, University of Bologna and S, Orsola-Malpighi Hospital, Bologna, Italy.
BMC Cancer. 2014 Jun 4;14:403. doi: 10.1186/1471-2407-14-403.
Development of escape pathways from antiangiogenic treatments was reported to be associated with enhanced tumor aggressiveness and rebound effect was suggested after treatment stop. Aim of the study was to evaluate tumor response simulating different conditions of administration of antiangiogenic treatment (transient or definitive treatment stop) in a mouse model of hepatocellular carcinoma.
Subcutaneous tumors were created by inoculating 5 × 10(6) Huh7 cells into the right flank of 14 nude mice. When tumor size reached 5-10 mm, mice were divided in 3 groups: group 1 was treated with placebo, group 2 was treated with sorafenib (62 mg/kg via gavage) but temporarily suspended from day +5 to +9, whereas in group 3 sorafenib was definitively stopped at day +5. At day +13 all mice were sacrificed, collecting masses for Western-Blot analyses. Volume was calculated with B-mode ultrasonography at day 0, +5, +9, +11 and +13. VEGFR2-targeted contrast-enhanced ultrasound using BR55 (Bracco Imaging) was performed at day +5 and +13 and elastonosography (Esaote) at day +9 and +11 to assess tumor stiffness.
Median growth percentage delta at day +13 versus day 0 was 197% (115-329) in group 1, 81% (48-144) in group 2 and 111% (27-167) in group 3. Median growth delta at day +13 with respect to day +5 was 79% (48-127), 37% (-14128) and 81% (15-87) in groups 1, 2 and 3, respectively. Quantification of targeted-CEUS at day +13 showed higher values in group 3 (509 Arbitrary Units AI, range 293-652) than group 1 (275 AI, range 191-494) and group 2 (181 AI, range 63-318) (p=0.033). Western-Blot analysis demonstrated higher VEGFR2 expression in group 3 with respect to group 1 and 2.
A transient interruption of antiangiogenic treatment does not impede restoration of tumor response, while a definitive interruption tends to stimulate a rebound of angiogenesis to higher level than without treatment.
据报道，抗血管生成治疗逃逸途径的形成与肿瘤侵袭性增强有关，且在治疗停止后提示有反弹效应。本研究的目的是在肝细胞癌小鼠模型中，模拟抗血管生成治疗的不同给药条件（短暂或彻底停止治疗）来评估肿瘤反应。
将5×10⁶个Huh7细胞接种到14只裸鼠的右腹侧以形成皮下肿瘤。当肿瘤大小达到5 - 10毫米时，将小鼠分为3组：第1组用安慰剂治疗，第2组用索拉非尼（通过灌胃给予62毫克/千克）治疗，但从第5天到第9天暂时停药，而第3组在第5天彻底停止索拉非尼治疗。在第13天处死所有小鼠，收集肿块进行蛋白质免疫印迹分析。在第0天、第5天、第9天、第11天和第13天用B型超声测量体积。在第5天和第13天使用BR55（博莱科影像公司）进行VEGFR2靶向超声造影，在第9天和第11天进行弹性成像（艾索特公司）以评估肿瘤硬度。
第13天相对于第0天的中位生长百分比变化在第1组为197%（115 - 329），第2组为81%（48 - 144），第3组为111%（27 - 167）。第13天相对于第5天的中位生长变化在第1组、第2组和第3组分别为79%（48 - 127）、37%（ - 14 - 128）和81%（15 - 87）。第13天靶向超声造影的定量分析显示，第3组（509任意单位AI，范围293 - 652）的值高于第1组（275 AI，范围191 - 494）和第2组（181 AI，范围63 - 318）（p = 0.033）。蛋白质免疫印迹分析表明，第3组的VEGFR2表达高于第1组和第2组。
抗血管生成治疗的短暂中断不会阻碍肿瘤反应的恢复，而彻底中断往往会刺激血管生成反弹至比未治疗时更高的水平。
