Besides the ability of some cancer cells to divide uncontrollably, what else could logically result in a tumor?

Other than the ability of some cancer cells to divide uncontrollably, the lack of appropriate cell death can logically result in tumor. When there is an occurrence of lack of appropriate cell death, this can lead to inappropriate tissue growth and tumor development. This is also characterized by altered mitochondrial metabolism. When there is a centrality of the dysfunction of the mitochondria in our system, there is surprisingly a wide range of major human diseases slowly becoming recognized. This brings along with it the prospect of novel therapeutic approaches to treat a multitude of unpleasant and pervasive diseases. We can therefore say that the there is a large and vital contribution of mitochondria in the maintenance of the normal cells in the body of an individual. 

cell would not be able to produce protein, got it from google