The present invention includes compounds useful in preventing, treating or ameliorating Sigma-related disorders or diseases. The compounds of the invention may modulate cellular protein homeostasis, which includes: translation initiation, folding, processing, transport, and degradation (including ubiquitin selective autophagy) of proteins. The present invention also includes methods of preventing, treating or ameliorating a Sigma-related disorder or disease in a subject in need thereof, the method comprising administering to the subject an effective amount of a Sigma-modulating compound. The present invention also includes methods of preventing, treating or ameliorating a Sigma-related disorder or disease in a subject in need thereof, the method comprising administering to the subject an effective amount of a Sigma-modulating compound, further comprising administering an effective amount of a compound that inhibits the ubiquitin proteasome system (UPS) and/or autophagic survival pathways.