口腔鳞状细胞癌（OSCC）是头颈癌中最常见的恶性肿瘤。口腔鳞癌是高度炎症、免疫抑制和侵袭性肿瘤。最近基于测序的研究表明，不同的口腔微生物群参与口腔疾病，导致 OSCC 的癌变、发生和进展。研究表明，口腔微生物群可以激活不同的炎症途径和癌症干细胞（CSC）相关的干性途径，从而促进肿瘤进展。我们推测 CSC 及其生态位细胞可能与微生物群相互作用，促进肿瘤进展和干细胞性。据报道，某些口腔微生物群与生态失调、癌前病变和口腔鳞癌的发展有关。这些特定微生物群的鉴定，包括人乳头瘤病毒 (HPV)、牙龈卟啉单胞菌 (PG) 和具核梭杆菌 (FN)，为我们研究细菌/干细胞以及促进 OSCC 发生的细菌/OSCC 细胞相互作用提供了新的机会、进展性和干性。重要的是，这些证据使我们能够开发体外和体内模型来研究微生物群与干细胞生态位防御以及 CSC 生态位防御的相互作用。因此，在这篇综述中，我们探讨了口腔微生物群在 OSCC 中的作用，特别关注口腔微生物群如何通过调节口腔粘膜干细胞和 CSC 生态位防御来诱导 OSCC 的发生和干性。版权所有 © 2023 Saikia、Pathak、Mitra 和 Das 。

Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy among the Head and Neck cancer. OSCCs are highly inflammatory, immune-suppressive, and aggressive tumors. Recent sequencing based studies demonstrated the involvement of different oral microbiota in oral cavity diseases leading OSCC carcinogenesis, initiation and progression. Researches showed that oral microbiota can activate different inflammatory pathways and cancer stem cells (CSCs) associated stemness pathways for tumor progression. We speculate that CSCs and their niche cells may interact with the microbiotas to promote tumor progression and stemness. Certain oral microbiotas are reported to be involved in dysbiosis, pre-cancerous lesions, and OSCC development. Identification of these specific microbiota including Human papillomavirus (HPV), Porphyromonas gingivalis (PG), and Fusobacterium nucleatum (FN) provides us with a new opportunity to study the bacteria/stem cell, as well as bacteria/OSCC cells interaction that promote OSCC initiation, progression and stemness. Importantly, these evidences enabled us to develop in-vitro and in-vivo models to study microbiota interaction with stem cell niche defense as well as CSC niche defense. Thus in this review, the role of oral microbiota in OSCC has been explored with a special focus on how oral microbiota induces OSCC initiation and stemness by modulating the oral mucosal stem cell and CSC niche defense.Copyright © 2023 Saikia, Pathak, Mitra and Das.