Recurrence biomarkers of triple negative breast cancer treated with neoadjuvant chemotherapy combined with anti-EGFR antibodies [Agilent]

To find metastatic recurrence biomarkers of triple negative breast cancer (TNBC) treated by neoadjuvant chemotherapy and anti-EGFR antibodies (NAT), we evaluated tumor genomic, transcriptomic and immune features, using MSK-IMPACT assay, gene arrays, Nanostring technology and TIL assessment on H&E. Six patients experienced a rapid fatal recurrence (RR) and other 6 had later non-fatal recurrences (LR). Before NAT, RR had low expression of 6 MHC class I and 13 MHC class II genes but were enriched in upregulated genes involved in the cell cycle-related pathways. Their TIL number before NAT in RR was very low (<5%) and did not increase after treatment. In post-NAT residual tumors, RR cases showed high expression of SOX2 and CXCR4. Our results indicate that high expression of cell cycle genes, combined with cold immunological phenotype, may predict strong TNBC resistance to NAT and rapid progression after it. This biomarker combination is worth validation in larger studies. Nucleic acids were extracted from frozen tumor tissue (pre-NAT samples) using AllPrep DNA/RNA mini kit (Qiagen France SAS, Courtaboeuf, France) according to the manufacturer’s protocol. RNA quality was verified using the 2100 BioAnalyzer (Agilent Technologies). The extracted material was sent to Helixio (Saint-Beauzire, France), where it was hybridized with gene arrays (Human SurePrint, Agilent Technologies France, Les Ullis, France).

为探寻接受新辅助化疗联合抗EGFR抗体治疗（NAT）的三阴性乳腺癌（TNBC）的转移性复发生物标志物，本研究采用MSK-IMPACT检测（MSK-IMPACT assay）、基因芯片、Nanostring技术以及基于H&E染色的肿瘤浸润淋巴细胞（TIL）评估方法，对肿瘤的基因组、转录组与免疫特征展开评估。6名患者出现快速致死性复发（RR），另有6名患者出现延迟性非致死性复发（LR）。新辅助治疗前，RR组患者的6种主要组织相容性复合体I类（MHC class I）基因与13种主要组织相容性复合体II类（MHC class II）基因表达水平较低，但其肿瘤组织中富集了细胞周期相关通路的上调基因；该组患者新辅助治疗前的TIL数量极低（<5%），且经治疗后未出现升高。在新辅助治疗后的残留肿瘤组织中，RR组患者的SOX2与CXCR4基因呈现高表达。本研究结果显示，细胞周期基因高表达联合免疫冷表型，或可预测三阴性乳腺癌对新辅助化疗联合抗EGFR抗体治疗的强耐药性，以及治疗后的快速疾病进展。该生物标志物组合值得在更大规模的研究中进行验证。本研究按照制造商说明书，采用AllPrep DNA/RNA迷你试剂盒（Qiagen France SAS, Courtaboeuf, France）从冰冻肿瘤组织（新辅助治疗前样本）中提取核酸；通过2100生物分析仪（Agilent Technologies）验证RNA质量；提取的样本被送至法国圣博齐尔的Helixio实验室，采用基因芯片（Human SurePrint, Agilent Technologies France, Les Ullis, France）完成杂交实验。