Knockdown of ribonuclease inhibitor expression with siRNA in non-invasive bladder cancer cell line BIU-87 promotes growth and metastasis potentials

• Published in: Molecular and cellular biochemistry Vol. 349; no. 1-2; pp. 83 - 95
• Main Authors: Chen, Junxia, Ou-Yang, Xi, Gao, Juan, Zhu, Jun, He, Xiaoyan, Rong, Jiang
• Format: Journal Article
• Language: English
• Published: Boston Boston : Springer US 01.03.2011; Springer US; Springer; Springer Nature B.V
• Subjects: Animals; Biochemistry; Biomedical and Life Sciences; Bladder; Bladder cancer; Bladder cancer cells; Cadherins - metabolism; Cardiology; Carrier Proteins - genetics; Carrier Proteins - metabolism; Cell Movement - genetics; Cell Proliferation; Cell Shape; Cellular biology; Collagenases - metabolism; Gene Knockdown Techniques; Genetic vectors; Growth; Health aspects; Humans; Life Sciences; Medical Biochemistry; Metastasis; Mice; Mice, Inbred BALB C; Mice, Nude; Neoplasm Invasiveness - genetics; Neoplasm Metastasis; Neoplasm Transplantation; Neovascularization, Pathologic - genetics; NM23 Nucleoside Diphosphate Kinases - metabolism; Oncology; Ribonuclease; Ribonuclease inhibitor; Ribonucleases; RNA; RNA Interference; RNA, Small Interfering - genetics; Rodents; small interfering RNA; Transplantation, Heterologous; Tumor Burden; Tumor growth; Tumors; Urinary Bladder Neoplasms - blood supply; Urinary Bladder Neoplasms - genetics; Urinary Bladder Neoplasms - pathology; Ribonuclease inhibitor; Small interfering RNA; Bladder cancer cells; Metastasis; Tumor growth
• ISSN: 0300-8177; 1573-4919
• DOI: 10.1007/s11010-010-0663-7

Human ribonuclease inhibitor (RI) is a cytoplasmic acidic protein. RI is constructed almost entirely of leucine-rich repeats, which might be involved in some unknown biological functions like other structurally similar proteins besides inhibiting RNase A and angiogenin activities. Our previous experiments demonstrated that up-regulating RI might effectively inhibit some tumor growth and metastasis. However, the down-regulating RI influence on the tumor does not have any report until now, the mechanisms underlying antitumor of RI have not been fully understood. In this study, the efficient RNA interferences of RI were constructed using a plasmid vector and identified with RT-PCR, Western blot and Immunocytochemistry, then were transfected into non-invasive bladder cancer BIU-87 cells. We demonstrated that knockdown RI expression in BIU-87 cells could obviously change the cell morphology, rearrange the microfilaments and extend the lamellipodia, as well as enhance proliferation, increase migration, invasion and matrix metalloprotease level, and also reduce adhesion in vitro. BALB/C nude mice that were injected with the BIU-87 cells transfected RI siRNA showed a significant facilitation of the tumor with heavier tumor weight, higher density of microvessels, lower nm23-H1 and E-Cadherin expressions than those in the control group. Taken together, these experiments suggest that knockdown of RI could promote growth and metastasis potentials of BIU-87 cells. Our present findings reveal the novel mechanism that anti-tumor effect of RI is also involved in suppressing growth and metastasis, besides antiangiogenesis. The results show that RI may be a therapeutic target protein for bladder cancer and may be of biological importance.