HPGDS and adenoma: In a study by Park et al. 74, which evaluated the possible influence of PGD2 on the development of intestinal adenomas, a 50% increase in intestinal adenomas was shown in the ApcMin/knockout mouse model for the hematopoietic PGD synthase (H-PGDS) enzyme, whereas in the ApcMin/+ mouse model with high expression of H-PGDS, an approximately 80% reduction in the adenomas was observed.