Furthermore, SSd was also reported to induce autophagy in HeLa and MCF-7 cancer cells by direct inhibition of sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA), leading to the increase of intracellular calcium ion levels and activating the Ca2+/calmodulin-dependent kinase kinase-β- (CaMKKβ-) AMP-activated protein kinase- (AMPK-) mammalian target of rapamycin (mTOR) signaling cascade, endoplasmic reticulum (ER) stress, and unfolded protein responses (UPR) [43]. Here, MTOR is linked to cancer.