Comparative Expression of the Mitotic Regulators SAK and PLK in Colorectal Cancer

Abstract

The polo family mitotic regulators SAK and PLK are both aberrantly expressed in colorectal cancer. The potential prognostic significance of SAK and PLK expression in colorectal cancer will be evaluated in the future.

Sak/Plk4 and mitotic fidelity

“…However, Sak transcripts were only modestly increased in human colorectal cancer tissue (T), as compared with adjacent normal mucosa (NM) (T : NM ratio of 1.3170.10, mean7s.e.m., n ¼ 71) . Analysis of Plk1 transcripts in the same specimens showed a mean T : NM ratio of 1.6270.13, consistent with reports of Plk1 overexpression in colorectal and other primary cancers (Wolf et al, 1997;Macmillan et al, 2001;Takahashi et al, 2003). Interestingly, a small group of colorectal cancer patients showed Sak transcript levels more than 2SD below the mean, without an associated reduction in Plk1 expression.…”

“…Sak expression is apparent only in proliferating cells, and correlates with proliferative index (Fode et al, 1994;Macmillan et al, 2001). However, Sak transcripts were only modestly increased in human colorectal cancer tissue (T), as compared with adjacent normal mucosa (NM) (T : NM ratio of 1.3170.10, mean7s.e.m., n ¼ 71) .…”

Polo-like kinases (Plks) and cancer

“…Levels of Plk1 expression in tumor relative to paired normal mucosa correlated directly with patient age and with each other but did not correlate with tumor stage. These results suggest a mechanism for augmented disruption of mitotic regulation in older patients (Macmillan et al, 2001).…”

Centrosome Abnormality and Human Lung Cancer

“…PLK4 is transcriptionally regulated by p53 . Clinically, the expression of PLK4 is upregulated in colon cancer (Macmillan et al, 2001), while the expression of PLK4 is downregulated in hepatocellular carcinoma because of promoter hypermethylation and the loss of heterozygosity (LOH) (Pellegrino et al, 2010;Rosario et al, 2010). The role of the morgana/chp-1 in centrosome regulation has been reported by Ferretti et al (2010).…”