TP53 and squamous cell carcinoma: 1. Massilia, Phenylobacterium, and Pseudoxanthomonas are mainly distributed in tumor tissues, while Brevibacillus, Cupriavidus, and Anaerococcus are more abundant in non-tumor tissues. 2. Brevundimonas, Ruminococcus, and Polaromonas differed between squamous cell carcinoma and adenocarcinoma. 3. More Massilia and Sphingobacterium and less Acidovorax in the tumor tissues of smokers4. Acidovorax and Massilia were rich in TP53 mutation-positive tumors.