ABSTRACT
Prostate cancer (PC) is the most common cancer diagnosed in men worldwide. Currently, castration-resistant prostate cancer (CRPC), which is resistant to androgen deprivation therapy, has a poor prognosis and is a therapeutic problem. We investigated the antitumor effects on PC of an antibody neutralizing secreted disintegrin and metalloproteinase domain-containing protein 9 (sADAM9), which is a blood-soluble form. We performed proliferation assays, wound healing assays, invasion assays, Western blot (WB), and an in vivo study in which a sADAM9 neutralizing antibody was administered intratumorally to PC-bearing mice. In invasion assays, the sADAM9 neutralizing antibody significantly inhibited invasion in all cell lines (TRAMP-C2: p = 0.00776, LNCaP: p = 0.000914, PC-3: p = 0.0327, and DU145: p = 0.0254). We examined epithelial-mesenchymal transition (EMT) markers, one of the metastatic mechanisms, in WB and showed downregulation of Slug in TRAMP-C2, LNCaP, and DU145 and upregulation of E-cadherin in TRAMP-C2 and PC-3 by sADAM9 neutralization. In mouse experiments, the sADAM9 neutralizing antibody significantly suppressed tumor growth compared to controls (1.68-fold in TRAMP-C2, 1.89-fold in LNCaP, and 2.67-fold in PC-3). These results suggested that the sADAM9 neutralizing antibody inhibits invasion, migration, and tumor growth in PC. Previous studies examined the anti-tumor effect of knockdown of total ADAM9 or sADAM9, but this study used the new technology of neutralizing antibodies for sADAM9. This may be novel because there was no animal study using a neutralizing antibody for sADAM9 to see the relationship between ADAM9 expression and prostate cancer.
Subject(s)
ADAM Proteins , Cell Movement , Epithelial-Mesenchymal Transition , Prostatic Neoplasms , Male , Epithelial-Mesenchymal Transition/drug effects , Animals , Humans , Cell Movement/drug effects , ADAM Proteins/metabolism , Mice , Cell Line, Tumor , Prostatic Neoplasms/pathology , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/drug therapy , Antibodies, Neutralizing/pharmacology , Cell Proliferation/drug effects , Membrane Proteins/metabolism , Xenograft Model Antitumor AssaysABSTRACT
Bladder cancer treatments are highly aggressive and have strong side effects. Safer and more effective treatments are needed. In this study, Dibenzolium (DIB), a potent NADPH oxidase inhibitor, was evaluated for its anti-tumor effects. KK-47 (non-invasive), T24 and 5637 (invasive) cells were used in experiments. Cell proliferation, apoptosis and wound healing assays and western blotting were conducted. In addition, DIB was intratumorally administered to mice bearing KK-47, T24 and 5637 tumors, and tumor size and weight were observed over time. After removing tumors, immunohistochemistry (IHC) staining was conducted. Cell proliferation was significantly suppressed in all cell lines, and apoptotic cells increased in the KK-47 and T24 cell lines after DIB. Wound healing was suppressed in all cell lines by DIB. In KK-47 and T24, DIB increased the protein expression of the epithelial marker E-cadherin. In vivo, DIB safely suppressed tumor growth in all cell lines-bearing mice. Cleaved-Caspase-3 and E-cadherin expression increased in KK-47 and T24 tumors after DIB. In conclusion, DIB inhibited tumor growth by inducing apoptosis through the Caspase-3 pathway and reduced migration and invasion by suppressing epithelial mesenchymal transition (EMT) in bladder cancer similarly shown as our previous study of prostate cancer.