Dr. Ganger et al., Differential expression of metallopanstimulin/S27 ribosomal protein in hepatic regeneration and neoplasia, CANCER DET, 25(3), 2001, pp. 231-236
We have previously shown that human metallopanstimulin-1 (MPS-1) is a ubiqu
itous 9.4-kd multifunctional ribosomal S27/nuclear "zinc finger" protein th
at is expressed at high levels in a wide variety of actively proliferating
cells and tumor tissues. In this study, we examined the expression of MPS-1
in chronic hepatitis, cirrhosis, and hepatocellular carcinoma. Tissue samp
les were obtained at the time of tumor resection, needle biopsy, or liver t
ransplantation. MPS-1 was studied by immunohistochemistry by use of specifi
c antibodies to the N-terminus of MPS-1 in a biotin/streptavidin-amplified
system. In chronic hepatitis, hepatocytes had very weak MPS-1 immunostainin
g. In contrast, hepatocytes in regenerating cirrhotic nodules stained stron
gly for MPS-1. In well-differentiated hepatocellular carcinoma, MPS-1 prese
nce was intense at the periphery of the malignant. nodule. In poorly differ
entiated hepatocellular carcinoma, MPS-1 presence was notably intense in ma
lignant hepatocytes invading the septal tissues, in close contact with neov
ascular structures. These results suggest that MPS-1 may be involved in bot
h progression toward malignancy in regenerating cirrhotic nodules and in su
bsequent steps of hepatocarcinogenesis.