ERBB2 and breast cancer: In a study by Li et al. (2018), a theranostic platform was developed in which bismuth sulfide nanoparticles were encapsulated with mesoporous silica and loaded with the chemotherapeutic agent doxorubicin, followed by functionalization with trastuzumab to target HER-2 positive breast cancer.85 This sophisticated nanoplatform, Tam-Bi2S3@mPS, combined the deep tissue imaging capabilities of bismuth with precise tumor targeting and dual-modality therapy.