Host metabolism: a target in clinical oncology?

The presence of the tumour induces important metabolic changes in the cancer patient which are not merely due to the fact that the tumour acts as a parasite, thus depleting the host of nutrients, but that are mainly the result of both tumoral and humoral mediators. The new metabolic status of the cancer patient may lead to cancer cachexia (a pathological state characterized by weight loss together with anorexia, weakness, anaemia and asthenia) which represents one of the worst effects of malignancy, accounting for nearly a third of cancer deaths. The complications associated with the appearance of the cachectic syndrome affect both the physiological and biochemical balance of the patient and have effects on the efficiency of the anticancer treatment, resulting in a considerably decreased survival time. At the metabolic level, cachexia is associated with loss of skeletal muscle protein together with a depletion of body lipid stores. The present study emphasizes the fact that neutralizing some of the metabolic changes in the patient may be an essential therapeutic strategy in controlling tumour growth and improving survival.