OBJECTIVES: Our previous study has verified that high level of SET and MYND domain-containing protein 2 (SMYD2) plays an important role in acquiring aggressive ability for liver cancer cells in hepatocellular carcinoma. MiR-200b as a tumor suppressor gene involves in a variety of cancers. This study aims to investigate the correlation between miR-200b and SMYD2 in hepatocellular carcinoma and the underlying mechanism. METHODS: Firstly, the levels of SMYD2 and miR-200b in hepatocellular carcinoma tissues and matched adjacent non-tumor liver tissues were tested with real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting. Secondly, we evaluated the interaction between miR-200b and SMYD2 using dual-luciferase reporter assay. Thirdly, we elucidated the effect of miR-200b on SMYD2 and its downstream targets p53/CyclinE1. Finally, we silenced SMYD2 in hepatocellular carcinoma cell lines to investigate its effect on tumor proliferation and cell cycle progression, and further confirmed the correlation among SMYD2 and p53/CyclinE1. RESULTS: Compared with the matched adjacent non-tumor liver tissues, miR-200b was obviously decreased, and SMYD2 was significantly increased in hepatocellular carcinoma (both P<0.05). Spearman's rank correlation revealed that miR-200b expression was negatively correlated with SMYD2 (P<0.01). Computer algorithm and dual-luciferase reporter assay revealed that miR-200b directly targeted and suppressed SMYD2 in HEK 293T cells. The down-regulated miR-200b expression promoted hepatoma cell proliferation (P<0.05) and increased SMYD2 expression(P<0.01), while the up-regulated expression of miR-200b had an opposite effect. The knockdown of SMYD2 suppressed the proliferation of MHCC-97L cells (P<0.01), down-regulated CyclinE1, and up-regulated p53 expression (both P<0.05). CONCLUSIONS MiR-200b is involved in hepatocellular carcinoma progression via targeting SMYD2 and regulating SMYD2/p53/CyclinE1 signaling pathway and may be used as a potential target for hepatocellular carcinoma treatment.
Humans ; Carcinoma, Hepatocellular/pathology* ; Tumor Suppressor Protein p53/metabolism* ; MicroRNAs/metabolism* ; Cell Line, Tumor ; Signal Transduction ; Liver Neoplasms/pathology* ; Cell Proliferation/genetics* ; Histone-Lysine N-Methyltransferase/metabolism*

OBJECTIVETacrolimus (FK506) is an immunosuppressive drug, which is widely used to prevent rejection of transplanted organs. However, chronic administration of FK506 leads to hypertension in solid organ transplantation patients, and its molecular mechanisms are much more complicated. In this review, we will discuss the above-mentioned molecular mechanisms of FK506-induced hypertension in solid organ transplantation subjects.

DATA SOURCESThe data analyzed in this review were mainly from relevant articles without restriction on the publication date reported in PubMed. The terms "FK506" or "tacrolimus" and "hypertension" were used for the literature search.

STUDY SELECTIONOriginal articles with no limitation of research design and critical reviews containing data relevant to FK506-induced hypertension and its molecular mechanisms were retrieved, reviewed and analyzed.

RESULTSThere are several molecular mechanisms attributed to FK506-induced hypertension in solid organ transplantation subjects. First, FK506 binds FK506 binding protein 12 and its related isoform 12.6 (FKBP12/12.6) and removes them from intracellular ryanodine receptors that induce a calcium ion leakage from the endoplasmic/sarcoplasmic reticulum. The conventional protein kinase C beta II (cPKCβII)-mediated phosphorylation of endothelial nitric oxide (NO) synthase at Thr495, which reduces the production of NO, was activated by calcium ion leakage. Second, transforming growth factor receptor/SMAD2/3 signaling activation plays an important role in Treg/Th17 cell imbalance in T cells which toget converge to cause inflammation, endothelial dysfunction, and hypertension following tacrolimus treatment. Third, the activation of with-no-K(Lys) kinases/STE20/SPS1-related proline/alanine-rich kinase/thiazide-sensitive sodium chloride co-transporter (WNKs/SPAK/NCC) pathway has a central role in tacrolimus-induced hypertension. Finally, the enhanced activity of renal renin-angiotensin-aldosterone system seems to play a crucial role in the pathophysiology of FK506-induced hypertension.

CONCLUSIONFK506 plays a predominant role in the pathophysiology of hypertension in solid organ transplantation subjects.

Humans ; Hypertension ; chemically induced ; Immunosuppressive Agents ; adverse effects ; therapeutic use ; Organ Transplantation ; adverse effects ; Tacrolimus ; adverse effects ; therapeutic use