At a high dose of MTX (12.50 mg/kg), MTX-HSA-NPs containing more biotin showed remarkable inhibition of tumor growth (approximately ten-fold lower in tumor volume than the non-targeted formulation) with an extended survival rate, suggesting that more biotin molecules allowed for more specific recognition of biotin-specific receptors on breast cancer cells, resulting in more cellular internalization of MTX and improved therapeutic responses [150]. This evidence concerns the gene ALB and breast carcinoma.