RT Journal Article SR Electronic T1 Immunohistochemical Quantification of the Vitamin B12 Transport Protein (TCII), Cell Surface Receptor (TCII-R) and Ki-67 in Human Tumor Xenografts JF Anticancer Research JO Anticancer Res FD International Institute of Anticancer Research SP 4203 OP 4212 VO 33 IS 10 A1 ANNETTE M. SYSEL A1 VICTOR E. VALLI A1 RAY B. NAGLE A1 JOSEPH A. BAUER YR 2013 UL http://ar.iiarjournals.org/content/33/10/4203.abstract AB Background/Aim: Cancer cells have an essential demand for vitamin B12 (cobalamin) to enable cellular replication. The present pilot study quantified the immunohistochemical expression of vitamin B12 transport protein (Transcobalamin II; TCII), cell surface receptor (Transcobalamin II-R; TCII-R) and proliferation protein (Ki-67) in human tumor xenografts. Materials and Methods: Tissue microarray slides containing 34 xenograft tumor tissues were immunohistochemically stained using TCN2 (anti-TCII), CD320 (anti-TCII-R) and MIB-1 (anti-Ki-67) antibodies. Representatively stained areas of all slides were digitally imaged and protein expression was quantified using ImageJ software plugins. Results: All xenograft tumor tissues stained positively for TCII, TCII-R and Ki-67 proteins; expression varied both within and between tumor types. Correlation between TCII/TCII-R and Ki-67 expression was not significant in xenograft tissues. Conclusion: Proliferating cancer cells express measurable levels of TCII and TCII-R. Immunohistochemical quantification of these markers may be useful as a tool for detection of tumors, tailored selection of anti-tumor therapies and surveillance for evidence of recurrent disease.