PMID- 31614472 OWN - NLM STAT- PubMed-not-MEDLINE LR - 20200928 IS - 2072-6694 (Print) IS - 2072-6694 (Electronic) IS - 2072-6694 (Linking) VI - 11 IP - 10 DP - 2019 Oct 11 TI - Natural Killer Cell Therapy: A New Treatment Paradigm for Solid Tumors. LID - 10.3390/cancers11101534 [doi] LID - 1534 AB - In treatments of solid tumors, adoptive transfer of ex vivo expanded natural killer (NK) cells has dawned as a new paradigm. Compared with cytotoxic T lymphocytes, NK cells take a unique position targeting tumor cells that evade the host immune surveillance by down-regulating self-antigen presentation. Recent findings highlighted that NK cells can even target cancer stem cells. The efficacy of allogeneic NK cells has been widely investigated in the treatment of hematologic malignancies. In solid tumors, both autologous and allogeneic NK cells have demonstrated potential efficacy. In allogeneic NK cell therapy, the mismatch between the killer cell immunoglobulin-like receptor (KIR) and human leukocyte antigen (HLA) can be harnessed to increase the antitumor activity. However, the allogeneic NK cells cause more adverse events and can be rejected by the host immune system after repeated injections. In this regard, the autologous NK cell therapy is safer. This article reviews the published results of clinical trials and discusses strategies to enhance the efficacy of the NK cell therapy. The difference in immunophenotype of the ex vivo expanded NK cells resulted from different culture methods may affect the final efficacy. Furthermore, currently available standard anticancer therapy, molecularly targeted agents, and checkpoint inhibitors may directly or indirectly enhance the efficacy of NK cell therapy. A recent study discovered that NK cell specific genetic defects are closely associated with the tumor immune microenvironment that determines clinical outcomes. This finding warrants future investigations to find the implication of NK cell specific genetic defects in cancer development and treatment, and NK cell deficiency syndrome should be revisited to enhance our understanding. Overall, it is clear that NK cell therapy is safe and promises a new paradigm for the treatment of solid tumors. FAU - Oh, Sooyeon AU - Oh S AD - Chaum Life Center, CHA University School of Medicine, Seoul 06062, Korea. ohsooyoun@hotmail.com. AD - Graduate school of Internal Medicine, Seoul National University College of Medicine, Seoul 03080, Korea. ohsooyoun@hotmail.com. FAU - Lee, Joo-Ho AU - Lee JH AD - Department of Gastroenterology and Hepatology, CHA Bundang Medical Center, CHA University School of Medicine, Seongnam 13496, Korea. piolee2000@naver.com. FAU - Kwack, KyuBum AU - Kwack K AD - Department of Biomedical Science, College of Life Science, CHA University, Seongnam 13488, Korea. kbkwack@cha.ac.kr. FAU - Choi, Sang-Woon AU - Choi SW AD - Chaum Life Center, CHA University School of Medicine, Seoul 06062, Korea. sangwoon.choi@gmail.com. AD - School of Public Health and Health Sciences, University of Massachusetts, Amherst, MA 01003, USA. sangwoon.choi@gmail.com. LA - eng PT - Journal Article PT - Review DEP - 20191011 PL - Switzerland TA - Cancers (Basel) JT - Cancers JID - 101526829 PMC - PMC6826624 OTO - NOTNLM OT - NK cell deficiency OT - allogeneic OT - autologous OT - immunotherapy OT - natural killer COIS- The authors declare no conflict of interest. EDAT- 2019/10/17 06:00 MHDA- 2019/10/17 06:01 PMCR- 2019/10/11 CRDT- 2019/10/17 06:00 PHST- 2019/07/02 00:00 [received] PHST- 2019/09/29 00:00 [revised] PHST- 2019/10/06 00:00 [accepted] PHST- 2019/10/17 06:00 [entrez] PHST- 2019/10/17 06:00 [pubmed] PHST- 2019/10/17 06:01 [medline] PHST- 2019/10/11 00:00 [pmc-release] AID - cancers11101534 [pii] AID - cancers-11-01534 [pii] AID - 10.3390/cancers11101534 [doi] PST - epublish SO - Cancers (Basel). 2019 Oct 11;11(10):1534. doi: 10.3390/cancers11101534.