Korean J Pathol.  2006 Oct;40(5):319-325.

Assessment of Apoptosis by M30 Immunoreactivity and the Relationship with the MSI status and the Clinicopathological Characteristics of Colorectal Carcinomas

• Kang HJ
• Sol MY
• Park DY
• Lee SH
• Shin DH
• Kim JY
• Choi KU
• Kim HW
• Lee CH
• Huh GY

Abstract

BACKGROUND: The monoclonal antibody M30 recognizes a neoepitope of cytokeratin 18 that's produced during the process of apoptosis, and it is reactive in formalin-fixed, paraffin-embedded tissue. The detailed nature of apoptosis in colorectal cancer is unclear, especially in regard to the MSI status and the clinicopathologic factors. The purpose of this study was to elucidate the apoptosis assessed by M30 immunoreactivity in colorectal cancer and its relationship with the MSI status and the various clinicopathologic factors of colorectal cancers.
METHODS
101 colorectal cancers were classified according to levels of MSI as 12 MSI-H, 4 MSI-L and 85 MSS. Apoptosis was quantified by immunohistochemistry with using M30 CytoDEATH anti-body.
RESULTS
The apoptotic index assessed by M30 was significantly increased in the MSI-H and MSI-L colorectal cancer compared to that in the MSS colorectal cancer. Right sided colon cancer showed a significant higher apoptotic index than did the left sided colon cancer. There was also a tendency for decreased apoptosis in metastatic colorectal cancers (Duke's stage D). There was somewhat of an increase of apoptosis in colorectal cancers with mucinous carcinoma and medullary carcinoma, and also in the colorectal cancers with an increased TIL count, but this was not statistically significant.
CONCLUSION
M30 immunoreactivity is a valuable method to detect apoptosis in formalin-fixed, paraffin-embedded tissue and it might explain that MSI-H colorectal cancer shows better clinical behavior than MSS colorectal cancer in regard to the increased apoptosis.

Keyword

M30; Apoptosis; Colorectal cancer; Microsatellite instability

MeSH Terms

Adenocarcinoma, Mucinous
Apoptosis*
Carcinoma, Medullary
Colonic Neoplasms
Colorectal Neoplasms*
Immunohistochemistry
Keratin-18
Microsatellite Instability
Keratin-18