skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Alpha B-crystallin promotes the invasion and metastasis of colorectal cancer via epithelial-mesenchymal transition

Journal Article · · Biochemical and Biophysical Research Communications
 [1];  [2];  [1];  [3];  [1]
  1. Department of Pathology and Pathophysiology, Medical School of Southeast University, Nanjing 210009 (China)
  2. Department of General Surgery, The Second Affiliated Hospital of Nanjing Medical University, Nanjing 210011 (China)
  3. Department of Pathology, Jiangsu Cancer Hospital, Nanjing 210009 (China)

Alpha B-crystallin (CRYAB, HSPB5) is a protein that was first discovered in the lens of the eye. It is a member of the small heat-shock protein family (sHsps). CRYAB functions primarily as a molecular chaperone to prevent the aggregation and degradation of damaged unfolded proteins due to cellular damage resulting from heat shock, radiation, oxidative stress, and other insults, thereby promoting cell survival and preventing apoptosis. In recent years, the role of CRYAB in tumorigenesis, tumor invasion, and metastasis has received increasing attention. CRYAB is highly expressed in a variety of cancers, including breast cancer, head and neck cancer, and kidney cancer, and is likely associated with the prognosis of cancer. However, few studies have examined CRYAB in colorectal cancer (CRC). To study the effect of CRYAB on CRC, we transfected the CRC cell line SW480, which expresses high levels of CRYAB, with a lentiviral vector that inhibits CRYAB expression. The messenger RNA (mRNA) and protein expression of CRYAB was examined in the transfected SW480 cells (Si-CRYAB) using quantitative real-time polymerase chain reaction (qPCR) and Western blotting (WB) assays. Moreover, a growth curve was plotted to examine the proliferation of Si-CRYAB cells, and transwell assays were used to examine the migration of Si-CRYAB cells. Apoptosis and the cell cycle were examined in Si-CRYAB cells using flow cytometry (FCM), and the tumorigenic capability of Si-CRYAB cells was assessed in a nude mouse tumor model. Immunohistochemistry (IHC) was employed to examine CRYAB protein expression and the markers of epithelial-mesenchymal transition (EMT), such as E-cadherin, fibronectin, vimentin, and slug, in tumor tissues from nude mice and clinical invasive CRC and hepatic metastasis specimens. The qPCR and WB results showed that CRYAB was downregulated at the protein and mRNA level in Si-CRYAB cells, and the growth curve indicated that the proliferation of Si-CRYAB cells was reduced. Moreover, Si-CRYAB cells exhibited reduced migration capability in the transwell assay as well as increased apoptosis and G1 arrest in the FCM assay. The tumorigenesis study in nude mice showed that Si-CRYAB cells formed smaller tumors, indicating decreased tumorigenic capability. IHC results showed reduced CRYAB expression and lower levels of EMT in Si-CRYAB cells, whereas clinical specimens of invasive CRC and hepatic metastases exhibited elevated CRYAB expression and enhanced levels of EMT. These results demonstrated that CRYAB promoted the invasion and metastasis of CRC tumor cells via EMT. - Highlights: • The CRC cell line SW480 experssed high levels of CRYAB. • Inhibition of CRYAB induced apoptosis and G1 arrest. • Inhibition of CRYAB exhibited decreased migration and tumorigenesis in nude mice. • CRYAB promoted CRC invasion and metastasis probably via EMT.

OSTI ID:
22719023
Journal Information:
Biochemical and Biophysical Research Communications, Vol. 489, Issue 4; Other Information: Copyright (c) 2017 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0006-291X
Country of Publication:
United States
Language:
English