ALS and Cancer

Amyotrophic Lateral Sclerosis (ALS) is a rare but very severe disease. In ALS patients, defect in motor neuron accompanied with muscle atrophy progresses rapidly that results in defect in locomotion, swallowing and respiration. Patients normally die in 2 to 5 years after the onset of disease, if the artificial ventilator is not equipped. However, up to now there is no effective therapy. A number of epidemiological studies suggested that ALS relates to cancer. It has been shown that prostate cancer survivors are associated with a decreased risk of ALS [1]. In the contrary, a significantly elevated risk of ALS among survivors of melanoma and tongue cancer has been also reported [1]. ALS and cancer share defects in various cellular processes including cell survival, cell death and cell cycle. However, in ALS the defects results in progressive defect of motor neuron, while in cancer it results in uncontrolled cell survival and proliferation [1]. More than thirty ALS-causing genes have been identified and every year still new ALS-causing gene is reported. Some of them appear to be involved in not only ALS but also cancer as summarized below and in Table 1.