TY - JOUR 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 SP - 4203 LP - 4212 VL - 33 IS - 10 AU - ANNETTE M. SYSEL AU - VICTOR E. VALLI AU - RAY B. NAGLE AU - JOSEPH A. BAUER Y1 - 2013/10/01 UR - http://ar.iiarjournals.org/content/33/10/4203.abstract N2 - 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. ER -