Investigation of gene mutations in canine alimentary large cell lymphoma

Canine alimentary lymphomas are classified into large cell and small cell lymphomas. Both lymphomas are known to be of T-cell origin in most cases, but the molecular biological backgrounds have not been clarified. In human intestinal T-cell lymphoma, the mutations in genes related to JAK-STAT pathway have been frequently observed. In this study, gene mutations in canine alimentary large cell lymphoma were comprehensively investigated, especially focusing on those in genes associated with the JAK-STAT pathway. irst, whole exome sequencing (WES) analysis was performed using tumor samples from 4 dogs with alimentary large cell lymphoma. In addition to the gene mutations identified by WES, two hotspots of mutations in STAT3 and one in STAT5B were analyzed by targeted next-generation sequencing in 31 additional cases with alimentary large cell lymphoma. Finally, Sanger sequencing analysis was performed to investigate the mutations in the whole protein-cording region of SOCS3, a gene in which a mutation was identified by WES.

犬消化道淋巴瘤（canine alimentary lymphomas）可分为大细胞淋巴瘤与小细胞淋巴瘤两类。已知两类淋巴瘤在多数情况下均为T细胞起源，但其分子生物学背景尚未阐明。在人类肠道T细胞淋巴瘤中，JAK-STAT信号通路（JAK-STAT pathway）相关基因的突变较为常见。本研究对犬消化道大细胞淋巴瘤的基因突变展开全面分析，重点聚焦于与JAK-STAT信号通路相关的基因变异。首先，本研究采集4例消化道大细胞淋巴瘤患犬的肿瘤样本，开展全外显子组测序（whole exome sequencing, WES）分析。除通过全外显子组测序检出的基因突变外，本研究还通过靶向下一代测序对另外31例消化道大细胞淋巴瘤病例的STAT3基因的2个突变热点位点及STAT5B基因的1个突变热点位点进行了突变检测。最后，本研究通过桑格测序（Sanger sequencing）对经全外显子组测序检出突变的SOCS3基因的全部蛋白编码区的突变情况进行了验证分析。