<qa>  What is the target of the PD-1 antibody?OVERVIEW This is a Phase 1, open-label, dose-escalation study of JS-001, a humanized monoclonal IgG4 antibody targeting the Programmed Death -1 PD-1. It is estimated that 18-36 subjects with advanced or recurrent solid tumors or lymphomas will be enrolled in the dose-escalation study. 