DNA methylation is a frequent change in epigenetics of leukemia. In the development of leukemia, methylation plays an important role in the genetic expression regulation and genetic structure stabilization. Hematopoietic stem cell transplantation (HSCT) and chemotherapy are the common methods to cure leukemia at present. Unfortunately, it is very hard to find suitable donor for transplantation, while the relapse and drug resistance are the unresolved problems in chemotherapy. Because of the reversibility of methylation, the drugs reducing the level of methylation become a new way to cure leukemia. Decitabine is the most common medicament used to reduce the level of methylation. In this article, the methylation and tumor, methylation and hematologic diseases, methylation detection methods, demethylation therapy in leukemia and so on are reviewed.
DNA Methylation ; Humans ; Leukemia

This study was purposed to investigate whether phenylhexyl isothiocyanate (PHI) can reduce p16 gene methylation level or not. The myeloma U226 cell line was cultured with PHI of 0, 5, 10 micromol/L for 72 hours, then DNA was extracted. Hydrosulfite was used to treat the genome DNA of healthy adult, PCR amplification was carried out by using this DNA as template. The gene chip detecting methylation changes of 3 CpG in promoter region of p16 gene was constructed by designing a pair of probes which contain one methylated and one unmethylated probes. This pair of probes was used to detect 3 consecutive sites of CpG island in p16 gene. The standard curve was constructed by using gene chip after the methylated and unmethylated DNA were mixed at different ratio. Then treated samples of U266 cells were dotted on gene chip, obtained results were compared with standard curve to get the quantitative results. The results indicated that the probes on chip had excellent reproducible ability and precision, the methylation level of p16 gene in U266 cells treated with 0, 5 and 10 micromol/L of PHI was determined as 78.2%, 61.7% and 54.8%, respectively. It is concluded that the PHI can reduce the methylation level of p16 gene in U266 cells.
Cell Line, Tumor ; CpG Islands ; DNA Methylation ; Down-Regulation ; Genes, p16 ; Humans ; Isothiocyanates ; pharmacology ; Oligonucleotide Array Sequence Analysis

In the fifth scientific and technological revolution， information technology is the first productivity， which has a great impact on the supply and demand of medical services. Generally， internet medicine is equivalent to the combination between health industry and information technology. "Healthy China" strategy is China's "priority development strategy"， which adheres to the principle of health equity， emphasizes the integration of health into all policies， and takes co-construction and sharing as the basic path. With implementing internet medicine， "Healthy China" strategy promotes the mobility of medical service with three tools： interconnection， data and artificial intelligence. This enhances the operation efficiency of overall medical and health system， and optimizes the allocation of medical resources. The future development of internet medicine follows the double helix mode driven by technology and policy， and the policy determines the development boundary of the industry. On the basis to ensure medical safety， we should explore the possibility of internet diagnosis and treatment further， and pay attention to the fairness of resource allocation while improving efficiency， so as to realize the co-construction and sharing of health services.

Internet medicine is not a concept of jurisprudence. China's current medical law system mainly focuses on main qualifications of the participants who conduct diagnosis and treatment. This paper focuses on several business models of the core element （diagnosis and treatment） in internet medicine， namely： online health consultation provided by internet medical platform， online diagnosis and treatment by internet hospital， and certain artificial intelligence（AI） medicine products that are specialized for diagnosis and treatment. This paper summarizes the development of these three business models， and analyzes the main problems in their development， including the legitimacy identification of online consultation， the dilemma of the development of internet hospitals， the impact of insufficient sample data on the development of medical AI， and the reverse restriction of regulatory difficulties to the development of internet medicine. The next step of developing internet medicine is to broaden the scope of internet diagnosis and treatment on the premise of medical safety， which will be based on the improvement of current regulatory system. It is urgent to build early risk warning system and supervision/ management mechanism for internet medicine.

The penetration and integration of internet with medical industry is apparently falling behind its interaction with other industries in terms of speed and scale. The main reason is due to the high risk and difficult supervision of internet medicine. Based on the regulatory context， this paper analyzes the endogenous and exogenous risk of internet medicine. The inherent characteristics of the internet （such as openness， diversity， multi subjectivity， virtuality， transparency， and high aggregation） lead to endogenous risks， including jurisdiction disputes， uncertainty of rights and obligations， security of personal information and medical information， monopoly. The lag of specific law in internet medicine， the lack of extensibility and synergy of traditional hierarchical regulatory system， the uncertainty of internet hospital regulatory policy details， the lack of technical specifications/operating procedures and other external system coverage in internet diagnosis and treatment lead to regulatory blind areas and exogenous risks. Based on the risk analysis， this paper discusses further construction of the mechanisms of risk assessment and regulation for internet medicine.

As a new form of medical industry， internet medicine has not only the endogenous risk of internet industry， but also the blind area and exogenous risk because of lagging regulation. With the continuous progress of internet information technology， online diagnosis and treatment will gradually integrate and reconstruct the traditional medical service. In the history of medical development， the emergence of new technologies generally has the characteristics of risk. Therefore， the supervision of internet medicine should adhere to the rule of inclusiveness and prudence， and take into account the cultivation of the market and standardized development. It should also build a regulatory community， coordinate governance from the four dimensions of legitimacy， compliance， rationality and superiority. Taking the law as the bottom line， we should make full use of early online warning monitoring， off-site supervision， online supervision， reputation mechanism and other measures to promote the innovative development of internet medicine under the framework of legal compliance.