Department of Genomic Medicine, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA.
Sci Rep. 2024 Jul 15;14(1):16300. doi: 10.1038/s41598-024-65939-9.
Adenoid cystic carcinoma (ACC) is a rare, usually slow-growing yet aggressive head and neck malignancy. Despite its clinical significance, our understanding of the cellular evolution and microenvironment in ACC remains limited. We investigated the intratumoral microbiomes of 50 ACC tumor tissues and 33 adjacent normal tissues using 16S rRNA gene sequencing. This allowed us to characterize the bacterial communities within the ACC and explore potential associations between the bacterial community structure, patient clinical characteristics, and tumor molecular features obtained through RNA sequencing. The bacterial composition in the ACC was significantly different from that in adjacent normal salivary tissue, and the ACC exhibited diverse levels of species richness. We identified two main microbial subtypes within the ACC: oral-like and gut-like. Oral-like microbiomes, characterized by increased diversity and abundance of Neisseria, Leptotrichia, Actinomyces, Streptococcus, Rothia, and Veillonella (commonly found in healthy oral cavities), were associated with a less aggressive ACC-II molecular subtype and improved patient outcomes. Notably, we identified the same oral genera in oral cancer and head and neck squamous cell carcinomas. In both cancers, they were part of shared oral communities associated with a more diverse microbiome, less aggressive tumor phenotype, and better survival that reveal the genera as potential pancancer biomarkers for favorable microbiomes in ACC and other head and neck cancers. Conversely, gut-like intratumoral microbiomes, which feature low diversity and colonization by gut mucus layer-degrading species, such as Bacteroides, Akkermansia, Blautia, Bifidobacterium, and Enterococcus, were associated with poorer outcomes. Elevated levels of Bacteroides thetaiotaomicron were independently associated with significantly worse survival and positively correlated with tumor cell biosynthesis of glycan-based cell membrane components.
腺样囊性癌（ACC）是一种罕见的、通常生长缓慢但具有侵袭性的头颈部恶性肿瘤。尽管其具有临床意义，但我们对 ACC 中的细胞进化和微环境的理解仍然有限。我们使用 16S rRNA 基因测序研究了 50 个 ACC 肿瘤组织和 33 个相邻正常组织的肿瘤内微生物组。这使我们能够描述 ACC 内的细菌群落，并探索细菌群落结构、患者临床特征和通过 RNA 测序获得的肿瘤分子特征之间的潜在关联。ACC 中的细菌组成与相邻正常唾液组织明显不同，并且 ACC 表现出不同水平的物种丰富度。我们在 ACC 中鉴定出两种主要的微生物亚型：口腔样和肠道样。口腔样微生物组的特征是多样性和丰度增加的奈瑟菌、勒克氏菌、放线菌、链球菌、罗氏菌和韦荣球菌（常见于健康口腔），与侵袭性较低的 ACC-II 分子亚型和改善的患者预后相关。值得注意的是，我们在口腔癌和头颈部鳞状细胞癌中发现了相同的口腔属。在这两种癌症中，它们是与更具多样性的微生物组、侵袭性较低的肿瘤表型和更好的生存相关的共享口腔群落的一部分，这表明这些属是 ACC 和其他头颈部癌症中有利微生物组的潜在泛癌生物标志物。相反，肠道样肿瘤内微生物组的特点是多样性低，并且定植于肠道黏液层降解物种，如拟杆菌、阿克曼氏菌、布劳特氏菌、双歧杆菌和肠球菌，与较差的预后相关。梭菌属丰度升高与显著更差的生存独立相关，并与肿瘤细胞糖基细胞膜成分的生物合成呈正相关。
