Fig 2: Tumor selectivity, effects on percent survival, and the putative regulatory mechanism. (a) Tumor selectivity. The tumor selectivity was defined as the ratio of ‘reduction in MTT-based viability of tumor cells’ to ‘reduction in MTT-based viability of non-tumor cells’. The double asterisk indicates p < 0.01. Two tumor cell lines (TRAMP and PC-3 cells) and three non-tumor cell lines (A5, adipose, and MC3T3 cells) were employed. Of note, N.D. means that the viability of non-tumor cells was stimulated. (b–d) Percent survival of all cancer patients with the low and high mRNA levels of PRSS8, PVRL2, and NID1. (e) Putative tumor-suppressing mechanism by urine from the post-prostatectomy patients.NID1, nidogen 1; PSA, prostate-specific antigen.

Fig 3: Antitumor effects of PRSS8, PVRL2, and NID1 on TRAMP prostate tumor cells. The single and double asterisks indicate p < 0.05 and 0.01, respectively. (a) Elevated levels of PRSS8, PVRL2, and NID1 in the urine samples from the post-prostatectomy patients. (b and c) Downregulation of TGFß, and upregulation of c-cas3 and p53 by the incubation of TRAMP prostate tumor cells with 1, 2 µg/mL of PRSS8 and PVRL2. (d and e) Reduction in the EdU-based proliferation and scratch-based migration of TRAMP cells by PRSS8 recombinant proteins. (f and g) Reduction in the EdU-based proliferation and scratch-based migration of TRAMP cells by PVRL2 recombinant proteins.c-cas3, cleaved caspase 3; CN, control; NID1, nidogen 1; PRSS8, prostasin; PVRL2, poliovirus receptor-related 2 or nectin 2; TGFß, transforming growth factor beta.

Fig 4: Differential role of NID1 in the extracellular and intracellular domains for TRAMP prostate tumor cells. The single and double asterisks indicate p < 0.05 and 0.01, respectively. (a) Extracellular NID1 as a tumor suppressor by downregulating TGFß and upregulating c-cas3 for apoptosis induction and p53 for tumor suppression. (b and c) Reduction in EdU-based proliferation and scratch-based motility of TRAMP cells by extracellular NID1. (d and e) Elevation in the EdU-based proliferation and scratch-based migration of TRAMP cells by the overexpression of NID1. (f) Upregulation of TGFß and Snail, and downregulation of c-cas3 in TRAMP cells by the overexpression of NID1. (g and h) Downregulation of TGFß and Snail, and upregulation of c-cas3 in TRAMP cells by the overexpression of PRSS8 and PVRL2.CN, control; c-cas3, cleaved caspase 3; NID1, nidogen 1; TGFß, transforming growth factor beta.