Preliminary study pointing out a significant alteration in the biochemical composition of MUC2 in colorectal mucinous carcinoma.
OBJECTIVE
In this study, we characterized colonic MUC2 mucin from a mucinous carcinoma cell line and tried to find out carcinoma-associated alterations by comparing the results with those obtained from its benign phenotype previously.


METHODS
The molecular size distribution of the extracted molecules and their reactivity with two different MUC2 polypeptide antibodies indicated the presence of precursor and mature forms of the mucin in both cell lines. Isopycnic density gradient centrifugation gave good resolution of mature and precursor forms of MUC2 as assessed by agarose gel electrophoresis. Using this approach, we compared the different forms of MUC2 between benign and malign colonic cells.


RESULTS
In the comparison, we detected some aberrant glycosylated MUC2 molecules in mucinous carcinoma cell line. Agarose gel electrophoretic analysis of the low-density fractions indicated that these molecules are more charged than precursors, however, they are smaller and/or less glycosylated than mature MUC2 molecules.


CONCLUSIONS
The identification of unusual partially glycosylated forms of the major colonic mucin MUC2 is novel and unexpected. Implication of defective processes in the post translational modification/ processing of MUC2 opens a new field in the cancer mucin biology.
Aksoy
N
N
Harran University, Medical Faculty, Department of Biochemistry, Sanliurfa, Turkey. saksoy@doruk.net.tr
Corfield
A P
AP
Sheehan
J K
JK
D002288:Adenocarcinoma, Mucinous / Q000737:chemistry*; D000236:Adenoma / Q000737:chemistry; D000818:Animals; D002460:Cell Line; D002500:Centrifugation, Isopycnic; D015179:Colorectal Neoplasms / Q000737:chemistry*; D004587:Electrophoresis, Agar Gel; D015870:Gene Expression; D006031:Glycosylation; D006801:Humans; D015151:Immunoblotting; D051379:Mice; D055262:Mucin-2; D009077:Mucins / Q000032:analysis* / Q000737:chemistry / Q000276:immunology
C524625:MUC2 protein, human; C524626:Muc2 protein, mouse; D055262:Mucin-2; D009077:Mucins