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Background Previously, we reported the expression of DLX4 isoforms (BP1 and DLX7) in myeloid leukemia, but the functional role of DLX4 isoforms remains poorly understood. In the work described herein, we further determined the underlying role of DLX4 isoforms in chronic myeloid leukemia (CML) leukemogenesis. Methods The expression and methylation of DLX4 isoforms were detected by real-time quantitative PCR (RT-qPCR) and real-time quantitative methylation-specific PCR (RT-qMSP) in patients with CML. The functional role of DLX4 isoforms was determined in vitro and in vivo. The molecular mechanism of DLX4 isoforms in leukemogenesis was identified based on chromatin immunoprecipitation with high-throughput sequencing (ChIP-Seq)/assay for transposase-accessible chromatin with high-throughput sequencing (ATAC-Seq) and RNA sequencing (RNA-Seq). Results BP1 expression was increased in patients with CML with unmethylated promoter, but DLX7 expression was decreased with hypermethylated promoter. Functionally, overexpression of BP1 increased the proliferation rate of K562 cells with S/G2 promotion, whereas DLX7 overexpression reduced the proliferation rate of K562 cells with G1 arrest. Moreover, K562 cells with BP1 overexpression increased the tumorigenicity in NCG mice, whereas K562 cells with DLX7 overexpression decreased the tumorigenicity. Mechanistically, a total of 91 genes including 79 messenger RNAs (mRNAs) and 12 long noncoding RNAs (lncRNAs) were discovered by ChIP-Seq and RNA-Seq as direct downstream targets of BP1. Among the downstream genes, knockdown of RREB1 and SGMS1-AS1 partially revived the proliferation caused by BP1 overexpression in K562 cells. Similarly, using ATAC-Seq and RNA-Seq, a total of 282 genes including 151 mRNA and 131 lncRNAs were identified as direct downstream targets of DLX7. Knockdown of downstream genes PTPRB and NEAT1 partially revived the proliferation caused by DLX7 overexpression in K562 cells. Finally, we also identified and validated a SGMS1-AS1/miR-181d-5p/SRPK2 competing endogenous RNA (ceRNA) network caused by BP1 overexpression in K562 cells. Conclusions The current findings reveal that DNA methylation-mediated differential expression of DLX4 isoforms BP1 and DLX7 plays opposite functions in leukemogenesis. BP1 plays an oncogenic role in leukemia development, whereas DLX7 acts as a tumor suppressor gene. These results suggest DLX4 as a therapeutic target for antileukemia therapy.

Background: Our previous studies have shown that regulatory factor X5 (RFX5), a classical transcription regulator of MHCII genes, was obviously overexpressed in hepatocellular carcinoma (HCC) tumors. However, the role of RFX5 in the carcinogenesis and progress of HCC remains unknown. This study aimed to reveal its biological significance and the underlying mechanism in HCC. Methods: RFX5 mRNA expression level and copy number variation in HCC tumors and cell lines were determined by analyzing deposited data sets in the Cancer Genome Atlas and Gene Expression Omnibus database. The biological significance of RFX5 in HCC was investigated by monitoring the colony formation and subcutaneous tumor growth capacity when RFX5 was silenced with lentiviral short hairpin RNA and CRISPR/Cas9 system in HCC cell lines. The downstream gene transcriptionally activated by RFX5 in HCC cells was determined by chromatin immunoprecipitation and luciferase reporter assay. The involvement of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein theta (YWHAQ) in HCC development was further determined by performing colony formation rescue assay and subcutaneous tumor growth rescue experiment. The association of YWHAQ with recurrence-free survival of patients with HCC was assessed by Kaplan-Meier analysis. Moreover, apoptosis level and the protein level of p53 pathway were determined to reveal the mechanism of RFX5 in driving HCC development. Results: RFX5 was amplified and highly overexpressed in HCC tumor tissues compared with the corresponding non-tumor tissues. The mRNA expression level of RFX5 was significantly correlated with its DNA copy number (r = 0.4, P < 0.001). Functional study demonstrated that RFX5 was required for both clonogenic forming in vitro and subcutaneous tumor growth in vivo of HCC cells. Further study identified YWHAQ, namely 14-3-3 tau, as a key downstream transcriptional target gene of RFX5, which was tightly regulated by RFX5 in HCC. Moreover, overexpression of YWHAQ largely rescued the clonogenic growth of HCC cells that was suppressed by RFX5 knockdown. In addition, overexpression of YWHAQ in primary tumor was linked to poor prognosis of patients with HCC. These results demonstrated that YWHAQ was a downstream effector of RFX5 in HCC. Notably, RFX5-YWHAQ pathway could protect cells from apoptosis by suppressing the p53 and Bax in HCC. Conclusion: RFX5 is a putative HCC driver gene that plays an important role in the development and progression of HCC by transactivating YWHAQ and suppressing apoptosis. Key words: Hepatocellular carcinoma; Transcription factor; Apoptosis; P53

Panax quinquefolium (American ginseng) is a perennial understory herb that has been widely used as a medicinal plant in China and other countries. Autotoxicity has been reported to be one of the major problems hindering the consecutive cultivation of American ginseng. However, the potential autotoxic compounds produced by the root of American ginseng are less well known. Here, we report the isolation and characterization of five groups of autotoxic compounds from aqueous extracts of the fibrous roots of American ginseng. Ether extracts of the water-soluble compounds were further analyzed and separated into seven fractions. Among them, the most autotoxic fraction (Fraction V) was subjected to GC/MS analysis, and 44 compounds were identified. Based on literature information, 14 individual compounds were selected and their autotoxic effects on seedling growth were further tested. The results revealed that, of these 14 compounds, 9 phenolic compounds significantly reduced the growth of seedlings in a concentration-dependent manner, while 5 aliphatic compounds showed modest inhibition at all three concentrations tested. Furthermore, we verified the existence of the autotoxic compounds in the plow layer soil of commercially cultivated American ginseng fields, and the concentration of these compounds as determined by HPLC analysis was in line with the concentration determined to be bioactive. Taken together, our study established a functional link between the compounds produced by American ginseng and their autotoxic effects.

Polo-like kinases (PLKs) family has long been known to be critical for cell cycle and recent studies have pointed to new dimensions of PLKs function in the nervous system. Our previous study has verified that the levels of PLK3 in the brain are severely downregulated in prion-related diseases. However, the associations of PLKs with prion protein remain unclear. In the present study, we confirmed that PrP protein constitutively interacts with PLK3 as determined by both in vitro and in vivo assays. Both the kinase domain and polo-box domain of PLK3 were proved to bind PrP proteins expressed in mammalian cell lines. Overexpression of PLK3 did not affect the level of wild-type PrP, but significantly decreased the levels of the mutated PrPs in cultured cells. The kinase domain appeared to be responsible for the clearance of abnormally aggregated PrPs, but this function seemed to be independent of its kinase activity. RNA-mediated knockdown of PLK3 obviously aggravated the accumulation of cytosolic PrPs. Moreover, PLK3 overexpression in a scrapie infected cell line caused notable reduce of PrP(Sc) level in a dose-dependent manner, but had minimal effect on the expression of PrP(C) in its normal partner cell line. Our findings here confirmed the molecular interaction between PLK3 and PrP and outlined the regulatory activity of PLK3 on the degradation of abnormal PrPs, even its pathogenic isoform PrP(Sc). We, therefore, assume that the recovery of PLK3 in the early stage of prion infection may be helpful to prevent the toxic accumulation of PrP(Sc) in the brain tissues.

In China, about 40% of traditional Chinese medicine (TCM) comes from cultivation in agrarian systems. The cropland is fundamental to the productions of medicinal plants, and the sustainable soil management is essential for sustainable using of the TCM resources, furthermore it affects the local economies of the medicinal plant production regions and the sustainable development of TCM agriculture. In this paper, the concept of the sustainable use of TCM cropland was discussed and the problems on sustainable soil management in China were analyzed from the aspects of resources and quality. The research advances in sustainable use of the medicinal plants cropland were reviewed from the aspects of continuous cropping obstacles, faming systems and degraded soil remediation. The strengthening research fields in the further were suggested.

To provide evidence for establishing an efficient method of growing Panax quinquefolium by rotation of crops.Four-year old P. quinquefolium was cultivated in water and soil cultures. Biological assays were conducted with the aqueous extracts of P. quinquefolius, Fructus Perillae and roots of Coix lacryma-jobi. P. quinquefolium was cultivated in the soil where purple Perilla frutesens and C. lacryma-jobi were grown previously. The effects of rotation were determined.The stems, leaves and fibrous roots of Panax quinquefolium contained allelopathic substances. When the concentration of the allelopathic substances exceeded 1g per kg soil, P. quinquefolius could not grow. On the other hand, when the concentration of allelopathic substances fell below 0.2 g per kg soil, the rate of seedling growth was decreased by 25%. When P. quinquefolius was cultivated in the soil in which purple Perilla frutesens had previously grown, or in the soil supplemented with Fructus Perillae, the rates of seedling growth and the yield were raised by 26.8% and 11.5% tively, in comparison with the controls.Rotation of Panax quinquefolium and Perilla frutesens was shown to be a good way for the cultivation of the former. During the growing process, application of Fructus Perillae to the soil could further enhance the growth and of Panax quinquefolium.

To provide basis of environmental factors of genuine crude drug, Salvia miltiorrhiza root.On-the-spot investigation and indoor chemical analysis were made to study the physicochemical properties of growing soil and content of inorganic elements of S. miltiorrhiza, and obtained data were analysed with SPSS 10.0 software.S. miltiorrhiza root of high harvest area accumulated Cu and Zn. In soil principal component analysis, no principal component was obvious. So the drug has good adaptability in ecological environment of soil.Ecological environment of soil isn't leading factor in forming genuine crude S. miltiorrhiza.

To provide basis for environmental factors of genuine crude Chinese angelica.On-the-spot investigation and indoor chemical analysis were made to study the physicochemical properties of cultivated soil of Chinese angelica.The physical properties and the organic matte and mineral nutrition of cultivated soil of Chinese angelica are best in Min County, Gansu Province. The ecological environment is the leading factor in forming genuine crude Chinese angelica.