The prognostic activity of acylglycerol kinase immunohistochemical expression in colon adenocarcinoma patients

Introduction
Adenocarcinoma of the colon and rectum (COAD) is one of the most commonly diagnosed cancers of the gastrointestinal system. Acylglycerol kinase (AGK) is a known lipid kinase producing lysophosphatidic acid (LPA) from monoacylglycerol. It is widely expressed in the heart, brain, kidney, and muscle. Moreover, AGK is a significant cancer-related gene and is upregulated in many human malignancies, e.g. prostate cancer, breast cancer, oral squamous cell carcinoma, hepatocellular carcinoma, and renal carcinoma. However, the expression pattern and clinical significance of AGK in colon adenocarcinoma patients, especially in individuals living in Europe, remain unclear.

Aim
The current study investigated the expression of AGK protein in colon adenocarcinoma samples to assess its prognostic significance by correlating its immunohistochemical expression with the clinicopathological variables and survival of individuals living in Poland.

Material and methods
Tissue specimens were received from 110 colon adenocarcinoma patients who underwent surgical resection at the Municipal Hospital in Jaworzno in 2013–2015. The paraffin-embedded specimens were cut into 4-µm-thick sections and incubated with rabbit polyclonal antibody to AGK (final dilution 1 : 500) (Invitrogen; cat. number PA5-28566).

Results and conclusions
AGK was strongly expressed in colon adenocarcinoma tissues in comparison to non-pathological colon specimens. The high level of AGK immunoexpression was demonstrated to be clearly correlated with the malignancy-related clinicopathological factors and 5-year overall survival rate of patients.