Background/Aim: The aim of the study was to use a triple-negative breast cancer (TNBC) patient-derived orthotopic xenograft (PDOX) model to examine the efficacy of oral recombinant methioninase (o-rMETase) against this recalcitrant disease. Materials and Methods: The TNBC tumor from a patient was implanted in the right 4th inguinal mammary fat pad of nude mice. Two weeks later, the mice underwent tumorectomy with grossly-negative surgical margins. Two days after tumorectomy the mice were divided in two groups: one control and one treated with o-rMETase. Results: Tumors recurred in all mice. On day 11, the mean recurrent tumor volumes were 936.7 mm3 in the control group and 450.9 mm3 in the o-rMETase group (p<0.05). On day 15, the mean recurrent tumor volumes were 3392.5 mm3 in the control group and 1603.5 mm3 in the o-rMETase group. The mean recurrent tumor weights were 2.1 g in the control group and 1.1 g in the o-rMETase group on day 15. Conclusion: o-rMETase is an effective adjuvant treatment for aggressive TNBC.

中文翻译：

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口服蛋氨酸酶抑制侵袭性三阴性乳腺癌 PDOX 小鼠模型的复发

背景/目的：该研究的目的是使用三阴性乳腺癌 (TNBC) 患者来源的原位异种移植 (PDOX) 模型来检查口服重组蛋氨酸酶 (o-rMETase) 对这种顽固性疾病的疗效。材料与方法：将患者的TNBC肿瘤植入裸鼠右侧第4腹股沟乳腺脂肪垫。两周后，小鼠接受了肿瘤切除术，手术切缘呈阴性。肿瘤切除术后两天，将小鼠分成两组：一组对照，一组用 o-rMETase 处理。结果：肿瘤在所有小鼠中复发。在第 11 天，对照组的平均复发肿瘤体积为 936.7 mm3，o-rMETase 组为 450.9 mm3（p<0.05）。在第 15 天，对照组的平均复发肿瘤体积为 3392.5 mm3，o-rMETase 组为 1603.5 mm3。