Curcumin converts Foxp3+ regulatory T cells to T helper 1 cells in patients with lung cancer

• Published in: Journal of cellular biochemistry Vol. 119; no. 2; pp. 1420 - 1428
• Main Authors: Zou, Jian Y., Su, Chun H., Luo, Hong H., Lei, Yi Y., Zeng, Bo, Zhu, Hao S., Chen, Zhen G.
• Format: Journal Article
• Language: English
• Published: United States Wiley Subscription Services, Inc 01.02.2018
• Subjects: Adult; Aged; Cancer; Cell culture; Curcumin; Curcumin - administration & dosage; Curcumin - pharmacology; Cytometry; Female; Flow cytometry; forkhead box protein‐3; Forkhead protein; Forkhead Transcription Factors - genetics; Forkhead Transcription Factors - metabolism; Foxp3 protein; Gene expression; Humans; Immunity; Immunological tolerance; Immunoregulation; Interferon; Interferon-gamma - metabolism; Interferon‐γ; Lung cancer; Lung Neoplasms - drug therapy; Lung Neoplasms - genetics; Lung Neoplasms - immunology; Lymphocytes; Lymphocytes T; Male; Middle Aged; Patients; regulatory T cells; T helper 1 cells; T-Lymphocytes, Regulatory - cytology; T-Lymphocytes, Regulatory - drug effects; T-Lymphocytes, Regulatory - metabolism; Th1 Cells - cytology; Th1 Cells - drug effects; Th1 Cells - metabolism; Therapy; Transcription; Tumor Cells, Cultured; lung cancer; regulatory T cells; T helper 1 cells; forkhead box protein-3; Interferon-γ
• DOI: 10.1002/jcb.26302
• ISSN: 0730-2312; 1097-4644

The regulatory T cells (Treg) play an important role in the tumor tolerance. The methods to regulate the Treg population in cancer‐bearing hosts are limited currently. The effect of curcumin on inhibiting cancer has been recognized, but the mechanism remains elusive. This study tests a hypothesis that administration of curcumin down regulates Tregs in lung cancer (LC) patients. In this study, a group of LC patients was treated with curcumin. The peripheral Tregs and T helper (Th) 1 cells were analyzed by flow cytometry. The mechanism by which curcumin regulated the Tregs was observed by cell culture approaches. The results showed that the frequency of peripheral Treg was markedly higher in LC patients than that in healthy subjects, which was suppressed after treating with curcumin for 2 weeks. The peripheral Th1 cells were increased in LC patients after the curcumin therapy. The data of the in vitro experiments showed that curcumin converted the LC patient‐isolated Tregs to Th1 cells via repressing the gene transcription of forkhead protein‐3 and increasing the expression of interferon‐γ. In conclusion, curcumin can convert LC patient‐isolated Tregs to Th1 cells. The results suggest that curcumin may improve the antitumor immunity by regulating the tumor specific immune tolerance. The frequency of peripheral Treg in lung cancer patients was suppressed after treating with curcumin for 2 weeks. The peripheral Th1 cells were increased in lung cancer patients after the curcumin therapy. Curcumin converted the lung cancer‐isolated Tregs to Th1 cells via repressing the gene transcription of forkhead protein‐3 and increasing the expression of interferon‐gamma.