SPINT2 and urothelial carcinoma: However, another study has reported amplification of the DPF-PPP1R14A-SPINT2-KCNK6 and ACTN4 loci on chromosome 19q13 in human bladder tumors [20] and of the chromosomal region19q13.12-q13.2 in human urothelial carcinomas, especially in invasive types [21, 22].