Interleukin-8, key marker for colorectal cancer treatment

Although IL-8 expression has been recently correlated with the tumorpathology of various carcinoma types, the role of IL-8 in tumor development and metastasis is still not fully understood and often discussed controversially. Moreover, it remains unclear whether IL-8 expression is related to cancer progression and metastatic potential in colorectal carcinoma tissues.

This issue was addressed by Dr. Rubie and colleagues from the University of the Saarland, Germany. The investigators report on a potential role of IL-8 in the development and metastatic spread of colorectal cancer in the October 7 issue of the World Journal of Gastroenterology.

The article investigates the expression profile of IL-8 in inflammatory (ulcerative colitis), non-malignant (colorectal adenoma) and CRC tissues of different tumor stages as well as in colorectal liver metastases (CRLM) along with their related primary colorectal tumors.

The major findings demonstrate significant IL-8 up-regulation in all inflammatory, non-malignant and malignant colorectal entities compared to their corresponding normal tissues. However, the magnitude of IL-8 expression in surgical CRC tissue specimens correlates with increasing tumor stages and, thus, also with the malignant status of colorectal cancer cells. Moreover, the investigators show for the first time that, irrespective of the tumor stage, IL-8 is significantly higher expressed in CRC tissues compared to inflammatory colorectal conditions and adenomas of the colon/rectum. Since such conditions often constitute prevalent pre-existing disease states in the pathogenesis of colorectal cancer, these results strongly suggest an association between IL-8 up-regulation and the development of CRC. In addition, significant IL-8 overexpression was found in CRLM in comparison to related primary colorectal tumors. Thus, this study not only suggests a correlation between IL-8 expression and the induction and progression of colorectal carcinoma, but also clearly points to a correlation between IL-8 expression and the development of CRLM.

“Monitoring the IL-8 expression level in CRC patients may potentially help to assess the course of cancerous conditions and the prognosis of patients with respect to the development of CRLM. In this respect it is conceivable to monitor the IL-8 expression level in CRC patients that show no diagnosable symptoms of CRLM at the time of presentation, but may still carry a high risk for developing such metastases. A significantly up-regulated level of IL-8 might thus be a useful tool to evaluate the prognosis of patients with CRC with meaningful consequences of treatment. Thus, patients with a higher risk of developing CRLM may receive different treatment compared to patients with a lower risk of developing CRLM.”

This study shows that IL-8 may serve as a useful indicator of poor prognosis and a putative target for the development of drugs in CRC therapy.