Research Papers:

Immunohistochemical quantification of the cobalamin transport protein, cell surface receptor and Ki-67 in naturally occurring canine and feline malignant tumors and in adjacent normal tissues

Annette M. Sysel, Victor E. Valli and Joseph A. Bauer _

PDF  |  HTML  |  Supplementary Files  |  How to cite

Oncotarget. 2015; 6:2331-2348. https://doi.org/10.18632/oncotarget.3206

Metrics: PDF 2643 views  |   HTML 4047 views  |   ?  


Annette M. Sysel1, Victor E. Valli2 and Joseph A. Bauer1

1 Bauer Research Foundation, Akron, Ohio, USA

2 VDx Veterinary Pathology Services, Davis, California, USA


Joseph A. Bauer, email:

Keywords: transcobalamin II, Ki-67, canine, feline, tumors

Received: October 29, 2014 Accepted: December 10, 2014 Published: December 11, 2014


Cancer cells have an obligate need for cobalamin (vitamin B12) to enable DNA synthesis necessary for cellular replication. This study quantified the immunohistochemical expression of the cobalamin transport protein (transcobalamin II; TCII), cell surface receptor (transcobalamin II-R; TCII-R) and proliferation protein (Ki-67) in naturally occurring canine and feline malignant tumors, and compared these results to expression in corresponding adjacent normal tissues. All malignant tumor tissues stained positively for TCII, TCII-R and Ki-67 proteins; expression varied both within and between tumor types. Expression of TCII, TCII-R and Ki-67 was significantly higher in malignant tumor tissues than in corresponding adjacent normal tissues in both species. There was a strong correlation between TCII and TCII-R expression, and a modest correlation between TCII-R and Ki-67 expression in both species; a modest association between TCII and Ki-67 expression was present in canine tissues only. These results demonstrate a quantifiable, synchronous up-regulation of TCII and TCII-R expression by proliferating canine and feline malignant tumors. The potential to utilize these proteins as biomarkers to identify neoplastic tissues, streamline therapeutic options, evaluate response to anti-tumor therapy and monitor for recurrent disease has important implications in the advancement of cancer management for both human and companion animal patients.

Creative Commons License All site content, except where otherwise noted, is licensed under a Creative Commons Attribution 4.0 License.
PII: 3206