ACHE and early-onset autosomal dominant Alzheimer disease: The impaired activity of (AChE) among cancer patients reported in this study and its physiological consequence of ACh accumulation, viewed with the decreased ACh among patients with Alzheimer’s disease (AD) leads to speculation of an intriguing hypothesis for a possible link between these three factors: 1- Impaired AChE/Accumulating Ach, 2- Cancer, and 3- AD.