title: Inhibition of the growth of human melanoma cells by methionine enkephalin.
abstract: Melanoma is an aggressive cancer, the incidence of which is increasing worldwide. Limited therapies are currently available, particularly following metastasis. The aim of the present study was to investigate the inhibiting effect of methionine enkephalin (MENK) on human melanoma via opioid receptors. The results of the present study revealed that MENK markedly regulates the proliferation of A375 cells, causing cell cycle arrest in G0/G1 phase and a decrease in the percentage of cells in S and G2/M phases. Reverse transcription‑quantitative polymerase chain reaction demonstrated that MENK treatment increased opioid receptor expression in A375 cells. Furthermore, the expression level of survivin, an inhibitory apoptotic protein, was 1.1% of the level in the control group in the MENK group following 48 h of treatment. In conclusion, the results of the present study revealed, to the best of our knowledge for the first time, that MENK may inhibit growth and induce apoptosis of A375 cells, and describes a potential mechanism underlying these effects. Therefore, MENK should be investigated as a primary therapy for human melanoma cancer and as an adjuvant to other chemotherapies. Further studies are required to develop an optimal strategy for the use of MENK for the treatment of human cancers.
authors.affiliation: Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, P.R. China.
authors.forename: Dong-Mei
authors.initials: DM
authors.lastname: Wang
authors.affiliation: Department of Immunology, School of Basic Medical Science, Liaoning Medical University, Jinzhou, Liaoning 121000, P.R. China.
authors.forename: Guang-Chuan
authors.initials: GC
authors.lastname: Wang
authors.affiliation: Department of Pathology, School of Basic Medical Science, Liaoning Medical University, Jinzhou, Liaoning 121000, P.R. China.
authors.forename: Jing
authors.initials: J
authors.lastname: Yang
authors.affiliation: Immune Therapeutics, Inc., Orlando, FL 32801, USA.
authors.forename: Nicolas P
authors.initials: NP
authors.lastname: Plotnikoff
authors.affiliation: Immune Therapeutics, Inc., Orlando, FL 32801, USA.
authors.forename: Noreen
authors.initials: N
authors.lastname: Griffin
authors.affiliation: Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, P.R. China.
authors.forename: Yu-Man
authors.initials: YM
authors.lastname: Han
authors.affiliation: Department of Dermatology, No. 1 Hospital, China Medical University, Shenyang, Liaoning 110001, P.R. China.
authors.forename: Rui-Qun
authors.initials: RQ
authors.lastname: Qi
authors.affiliation: Department of Dermatology, No. 1 Hospital, China Medical University, Shenyang, Liaoning 110001, P.R. China.
authors.forename: Xing-Hua
authors.initials: XH
authors.lastname: Gao
authors.affiliation: Department of Immunology, School of Basic Medical Science, China Medical University, Shenyang, Liaoning 110122, P.R. China.
authors.forename: Feng-Ping
authors.initials: FP
authors.lastname: Shan
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D059447:Cell Cycle Checkpoints / Q000187:drug effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004744:Enkephalin, Methionine / Q000494:pharmacology*; D015870:Gene Expression; D006801:Humans; D008545:Melanoma / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011957:Receptors, Opioid / Q000235:genetics / Q000378:metabolism
chemical_list: D000970:Antineoplastic Agents; D012333:RNA, Messenger; D011957:Receptors, Opioid; D004744:Enkephalin, Methionine