HAVCR2 and breast cancer: Many emerging immune checkpoints targets, e.g., lymphocyte activation gene-3 (LAG-3), T-cell immunoglobulin and mucin domain-containing protein 3 (TIM-3), T-cell immunoglobulin and ITIM domain (TIGIT) and B7-H3, are either in the clinical trial or under active development in breast cancer [205].