MUC3A and gastric adenocarcinoma: Regarding associations between bacterial genera and intestinal mucin expression, depletion in Streptococcus was identified in gastric adenocarcinomas with high MUC2 mRNA levels (Fig. 4; Fig. S6) and Lactobacillus was significantly more abundant in tumors with mid-level MUC4 mRNA expression (Fig. 4; Fig. S7).