Buchsbaum Donald J, Bonner James A, Grizzle William E, Stackhouse Murray A, Carpenter Mark, Hicklin Daniel J, Bohlen Peter, Raisch Kevin P
Department of Radiation Oncology, University of Alabama at Birmingham, Wallace Tumor Institute, Room 674, 1824 6th Avenue South, Birmingham, AL 35294, USA.
Int J Radiat Oncol Biol Phys. 2002 Nov 15;54(4):1180-93. doi: 10.1016/s0360-3016(02)03788-4.
To investigate treatment of human pancreatic cancer cell lines and xenografts with combinations of Erbitux (IMC-C225) anti-epidermal growth factor receptor (EGFR) antibody, gemcitabine, and radiation.
BxPC-3 and MiaPaCa-2 human pancreatic carcinoma cells were treated in vitro for 24 h with IMC-C225 (5 microg/mL), then exposed to epidermal growth factor (EGF) (10 mM) for 5 min. Immunoblots were screened for EGFR expression and the ability of IMC-C225 to block EGF-induced tyrosine phosphorylation of EGFR. Cells were treated with IMC-C225 (5 microg/mL) on Day 0, the IC(50) dose of gemcitabine on Day 1 for 24 h, followed by 3 Gy 60Co irradiation on Day 2, or the combination of each agent. For cell proliferation, cells were counted on Day 4, and for apoptosis, cells were stained with annexin V-FITC and propidium iodide, then analyzed by FACS. Cells were treated with the same single or multiple treatments and analyzed in a clonogenic cell survival assay. The effect of IMC-C225, gemcitabine, and radiation on the growth of BxPC-3 and MiaPaCa-2 tumor xenografts was determined. Athymic nude mice bearing established s.c. tumor xenografts of 6-8 mm diameter received 6 weeks of treatment with IMC-C225 (1 mg every 3 days x 6) alone or in combination with gemcitabine (120 mg/kg i.v. every 6 days x 6), and 6 weekly fractions of 3 Gy radiation on the days after gemcitabine administration. Tumor growth was measured with Vernier calipers.
BxPC-3 and MiaPaCa-2 cell lines expressed low levels of EGFR. IMC-C225 inhibited EGF-induced tyrosine phosphorylation of the EGF receptor on both cell lines. Treatment of cells with a combination of IMC-C225 + gemcitabine + radiation produced the highest induction of apoptosis and inhibition of proliferation in vitro. Combination treatment with IMC-C225, gemcitabine, and radiation produced 100% complete regression of MiaPaCa-2 tumors for more than 250 days, and the greatest growth inhibition of BxPC-3 tumors compared to any single or dual treatments.
The IMC-C225 therapy in combination with gemcitabine chemotherapy and radiation therapy demonstrated statistically significantly greater efficacy over the single and double combination therapies. This form of multimodality treatment shows potential clinical application in the treatment of pancreatic cancer in humans.
研究爱必妥（IMC-C225）抗表皮生长因子受体（EGFR）抗体、吉西他滨与放疗联合应用对人胰腺癌细胞系及异种移植瘤的治疗效果。
用IMC-C225（5微克/毫升）对BxPC-3和MiaPaCa-2人胰腺癌细胞进行体外处理24小时，然后暴露于表皮生长因子（EGF）（10毫摩尔）中5分钟。通过免疫印迹法检测EGFR表达以及IMC-C225阻断EGF诱导的EGFR酪氨酸磷酸化的能力。在第0天用IMC-C225（5微克/毫升）处理细胞，第1天用吉西他滨的半数抑制浓度（IC50）剂量处理24小时，接着在第2天进行3戈瑞的60钴照射，或者使用各药物的联合组合。对于细胞增殖，在第4天对细胞进行计数；对于细胞凋亡，用膜联蛋白V-异硫氰酸荧光素（annexin V-FITC）和碘化丙啶对细胞进行染色，然后通过流式细胞术进行分析。用相同的单一或多种处理方式处理细胞，并在克隆形成细胞存活试验中进行分析。确定IMC-C225、吉西他滨和放疗对BxPC-3和MiaPaCa-2肿瘤异种移植瘤生长的影响。对携带直径6 - 8毫米皮下肿瘤异种移植瘤的无胸腺裸鼠，单独给予IMC-C225（每3天1毫克×6次）或与吉西他滨（每6天静脉注射120毫克/千克×6次）联合治疗6周，并在给予吉西他滨后的日子里每周进行6次每次3戈瑞的放疗。用游标卡尺测量肿瘤生长情况。
BxPC-3和MiaPaCa-2细胞系表达低水平的EGFR。IMC-C225抑制两种细胞系中EGF诱导的EGF受体酪氨酸磷酸化。用IMC-C225 + 吉西他滨 + 放疗联合处理细胞在体外产生了最高的细胞凋亡诱导率和增殖抑制率。IMC-C225、吉西他滨和放疗联合治疗使MiaPaCa-2肿瘤完全消退达100%超过250天，与任何单一或双重治疗相比，对BxPC-3肿瘤的生长抑制作用最大。
与单一和双重联合疗法相比，IMC-C225疗法联合吉西他滨化疗和放疗在统计学上显示出显著更高的疗效。这种多模式治疗形式在人类胰腺癌治疗中显示出潜在的临床应用价值。
