To the Editor

The article by Konta et al. (2008) on the relationship between CC chemokine ligand 5 (CCL5) genotype and urinary albumin excretion in the nondiabetic Japanese general population is highly interesting. The study by Konta et al. adds to the growing array of pathological conditions in which CCL5 plays a major role. Interestingly, CCL5 has recently been implicated in the etiopathogenesis of a number of systemic malignancies.

For instance, Luboshits et al. (1999), in a recent study, have shown that advanced breast cancers are associated with increased expression of CCL5. CCL5 has also been shown to be a significant predictor of progression in patients with stage II breast cancer (Hahoshen et al. 2006). In another study, tumors that expressed higher levels of CCL5 were more likely to metastasize in comparison with tumors that did not express as much CCL5 (Stormes et al. 2005). Vaday et al. (2006), in another recent study, have shown that CCL5 increases the proliferation and growth of prostate cancer cells. It is also believed that altered expression of CCL5 by T lymphocytes infected with human T-cell leukemia viruses may play a role in the pathogenesis of adult T-cell leukemia (Mori et al. 2004). Similarly, overexpression of CCL5 has been demonstrated in tumors such as mantle-cell lymphomas (Ek et al. 2006). Aldinucci et al. (2008), in a recent study, demonstrated inhibition of proliferation of Hodgkin’s lymphoma cell lines with the use of anti-CCL5 monoclonal antibodies, clearly confirming the role of CCL5 in the pathogenesis of these tumors.

CCL5 levels are also increased in a wide spectrum of other diseases, such as idiopathic inflammatory myopathies (Civatte et al. 2005) and chronic gastritis (Ohtani et al. 2004). The recent study by Konta et al. further adds to diseases in which CCL5 plays a major pathogenetic role. Further studies are needed to identify potent and safe inhibitors of CCL5 for better management of these diseases ranging from breast cancer to nondiabetic albuminuria.