Fijneman, R.J.A. et al. Expression of Pla2g2a prevents carcinogenesis in Muc2-deficient mice. Cancer Sci. 99, 2113-2119

Department of Pathology, VU University Medical Centre, Amsterdam, The Netherlands.
Cancer Science (Impact Factor: 3.52). 12/2008; 99(11):2113-9. DOI: 10.1111/j.1349-7006.2008.00924.x
Source: PubMed


Goblet cell depletion and down-regulation of MUC2 expression are observed in a significant percentage of human non-mucinous colorectal adenocarcinomas. Direct evidence for the role of MUC2 in gastrointestinal tumor formation was demonstrated by a knockout of Muc2 in mice that resulted in the development of adenocarcinomas in the small and large intestine. The secretory phospholipase Pla2g2a is a protein that confers resistance to Apc(Min/+)-induced intestinal tumorigenesis. Like Muc2, in the large intestine Pla2g2a is exclusively expressed by the goblet cells and Pla2g2a's tumor resistance is also strongest in the large intestine. Possible genetic interactions between Muc2 and Pla2g2a were examined by creating C57BL/6-Muc2(-/-)Pla2g2a transgenic mice. Expression of a Pla2g2a transgene reduced tumorigenesis in the large intestine by 90% in male Muc2(-/-) mice and by nearly 100% in female Muc2(-/-) mice. Expression of Pla2g2a also inhibited tumor progression. Microarray gene expression studies revealed Pla2g2a target genes that modulate intestinal energy metabolism, differentiation, inflammation, immune responses and proliferation. Overall, results of the present study demonstrate an Apc-independent role for Pla2g2a in tumor resistance and indicate that Pla2g2a plays an important role, along with Muc2, in protection of the intestinal mucosa.

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Available from: Ilze Matise, Oct 14, 2014
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    • "This may explain the contradictory reports and difficulty in assigning a clear role for a particular sPLA 2 in various cancers. For example, the role of GIIA sPLA 2 in colon cancer is still controversial , and several groups have found opposing effects on tumour progression, suggesting that GIIA may suppress carcinogenesis at early stages of tumour development, while promoting it at later stages [23] [24]. Given that the biological roles of sPLA 2 s are diverse and depend on the enzyme studied, its expression level and the tissue involved, the differential epigenetic regulation, shown here for breast cancer cells, adds another layer of complexity to their role in cancer and human (patho)physiology in general. "
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