RAD51 and neuroendocrine neoplasm: The RAD51 inhibitor amuvatinib sensitizes tumor cells to radio/chemotherapy by inhibiting RAD51 and HR in vitro and in vivo.94 A phase 1B clinical study showed amuvatinib was well tolerated and exhibited antitumor activity when combined with chemotherapy in neuroendocrine tumors and lung cancer.59 Clinical trials showed that PARP inhibitors, including olaparib, niraparib, and rucaparib, provided promising clinical benefits compared with traditional chemo/radiotherapy alone in BRCA1 or BRCA2 mutated ovarian cancer patients.60–62