Is inactivation of p16INK4a by CpG hypermethylation a frequent event in colorectal cancer?
p16(INK4a) promoter methylation, although common in colorectal cancer, does not result in a clinicopathologically distinct subgroup of tumors and infrequently results in transcriptional silencing. This suggests that p16(INK4a) gene inactivation does not have an important role in the pathogenesis of sporadic colorectal cancer.
A conceptual analysis shows that it is not obvious that oral infections cause CVD and that the question of causality does not only involve descriptive issues of science but also moral matters of society. Hence, whether oral infections cause CVD is an ethical and not only a scientific issue.