Localization of mucin (MUC2 and MUC3) messenger RNA and peptide expression in human normal intestine and colon cancer.
OBJECTIVE
Several studies have reported Northern blot data showing that mucin is expressed in a tissue-specific manner. To determine whether expression is limited to specific cell types within these tissues requires histological analysis.


METHODS
Both immunocytochemistry and in situ hybridization were used to identify cell types expressing the MUC2 and MUC3 mucins in the human small intestine, colon, and colon carcinoma.


RESULTS
In the normal small intestine and colon, an antibody recognizing the MUC2 apomucin stained goblet cells. In contrast, an antibody recognizing the MUC3 apomucin stained both goblet and absorptive cells. Consistent with this, in situ hybridization showed MUC2 messenger RNA (mRNA) only in goblet cells and MUC3 mRNA in both goblet and absorptive cells. In several samples of moderately well-differentiated colon cancer, MUC2 and MUC3 showed distinct patterns of expression, but the expression level of each was reduced compared with levels in normal tissue; there was considerable tumor-to-tumor and cell-to-cell variability using both mucin antibodies and complementary DNA probes.


CONCLUSIONS
Individual mucin genes have distinct patterns of expression within mucin-producing tissues, suggesting that the various mucin gene products play distinct functional roles.
Gastrointestinal Research Laboratory, Veterans Affairs Medical Center, San Francisco, California.
S K
SK
Chang
A F
AF
Dohrman
C B
CB
Basbaum
S B
SB
Ho
T
T
Tsuda
N W
NW
Toribara
J R
JR
Gum
Y S
YS
Kim
D003106:Colon / Q000737:chemistry / Q000166:cytology; D003110:Colonic Neoplasms / Q000737:chemistry* / Q000473:pathology; D004247:DNA / Q000032:analysis / Q000235:genetics; D004273:DNA, Neoplasm / Q000032:analysis / Q000235:genetics; D005752:Gastric Mucins; D006801:Humans; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D007421:Intestine, Small / Q000737:chemistry* / Q000166:cytology; D009077:Mucins / Q000032:analysis* / Q000235:genetics* / Q000502:physiology; D010455:Peptides / Q000032:analysis* / Q000235:genetics* / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis* / Q000235:genetics
D004273:DNA, Neoplasm; D005752:Gastric Mucins; D009077:Mucins; D010455:Peptides; D012333:RNA, Messenger; C053366:apomucin; D004247:DNA