PTEN and neoplasm: However, an inflammatory response in the eye could damage other tissues like the lens and retina, and long-term deletion of pten, a tumor-suppressor gene, could be detrimental clinically.77 In addition, previously, CNTF has been shown to induce regeneration of severed optic axons up to and beyond the optic chiasm, but this caused aberrant growth and misguidance of the axons.39