B7H3 / CD276 DSRCT high cell surface positivity - 96% of DSRCT samples positive in 2017 radioimmunotherapy trial > [!abstract]+ [Management of Desmoplastic Small Round Cell Tumor - Semin Pediatr Surg. 2017](https://pmc.ncbi.nlm.nih.gov/articles/PMC5614508/) > **Ninety-six percent of DSRCT samples were found to exhibit notable cell-surface expression of the immunomodulatory molecule B7H3, which has limited expression in normal tissue.** > The murine monoclonal antibody 8H9 targets B7H3, and intraperitoneal administration of the radioimmunonjugate 131I-8H9 has been investigated in a phase I trial in 34 patients with DSRCT at MSKCC [NCT01099644](https://clinicaltrials.gov/ct2/show/NCT01099644). Preliminary data on the first 13 patients demonstrated that treatment was well tolerated, and 6 of 7 patients treated after surgical debulking remained in remission at a median of 11 months post-therapy. Absorbed radiation doses to vital organs were well below tolerable levels. (..) Based on these encouraging observations, a phase II study combining 8H9-mediated radioimmunotherapy with external beam radiotherapy will be initiated in 2016.” B7H3 inhibits CD8 T cell response. Want to counter that. <span class="sidenote">This is a side note that will appear in the margin.</span> Some miRNA’s affect B7H3 expression.