In a study on human cervical cancer HeLA cells, either treatment with a low dose of naltrexone (NTX) or knockdown of the OGFRs combined with low dose NTX administration affected significantly E-/N-cadherin, vimentin, and SNAIL expression, resulting in restoration of a more epithelial and less invasive phenotype of cancer cells (Table 2). Here, SNAI1 is linked to cancer.