Arsenic disulfide induced apoptosis and concurrently promoted erythroid differentiation in cytokine-dependent myelodysplastic syndrome-progressed leukemia cell line F-36p with complex karyotype including monosomy 7

Realgar (α-As4S4) Treats Myelodysplasic Syndromes through Reducing DNA Hypermethylation

DNA hypermethylation is an epigenetic modification that plays a critical role in the oncogenesis of myelodysplastic syndromes (MDS). Aberrant DNA methylation represses the transcription of promotors of tumor suppressor genes, inducing gene silencing. Realgar (α-As₄S₄) is a traditional medicine used for the treatment of various diseases in the ancient time. Realgar was reported to have efficacy for acute promyelocytic leukemia (APL). It has been demonstrated that realgar could efficiently reduce DNA hypermethylation of MDS. This review discusses the mechanisms of realgar on inhibiting DNA hypermethylation of MDS, as well as the species and metabolisms of arsenic in vivo.

Arsenic-Containing Qinghuang Powder () is an Alternative Treatment for Elderly Acute Myeloid Leukemia Patients Refusing Low-Intensity Chemotherapy

OBJECTIVE

To analyze the overall survival (OS) of elderly acute myeloid leukemia (AML) patients treated with oral arsenic-containing Qinghuang Powder (, QHP) or low-intensity chemotherapy (LIC).

METHODS

Forty-two elderly AML patients treated with intravenous or subcutaneous LIC (1 month for each course, at least 3 courses) or oral QHP (3 months for each course, at least 2 courses) were retrospectively analyzed from January 2015 to December 2017. The main endpoints of analysis were OS and 1-, 2-, 3-year OS rates of patients, respectively. And the adverse reactions induding bone marrow suppression, digestive tract discomfort and myocardia injury were observed.

RESULTS

Out of 42 elderly AML patients, 22 received LIC treatment and 20 received QHP treatment, according to patients' preference. There was no significant difference on OS between LIC and QHP patients (13.0 months vs. 13.5 months, >0.05). There was no significant difference on OS rates between LIC and QHP groups at 1 year (59.1% vs. 70.0%), 2 years (13.6% vs. 15%), and 3 years (4.6% vs. 5.0%, all >0.05). Furthermore, there was no significant difference of OS on prognosis stratification of performance status > 2 (12 months vs. 12 months), age> 75 year-old (12.0 months vs. 12.5 months), hematopoietic stem cell transplant comorbidity index >2 (12 months vs. 13 months), poor cytogenetics (12 months vs. 8 months), and diagnosis of secondary AML (10 months vs. 14 months) between LIC and QHP patients (>0.05).

CONCLUSION

QHP may be an alternative treatment for elderly AML patients refusing LIC therapy.

Molecular cloning and metabolomic characterization of the 5-enolpyruvylshikimate-3-phosphate synthase gene from Baphicacanthus cusia

BACKGROUND

Indigo alkaloids, such as indigo, indirubin and its derivatives, have been identified as effective antiviral compounds in Baphicacanthus cusia. Evidence suggests that the biosynthesis of indigo alkaloids in plants occurs via the shikimate pathway. The enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) is involved in plant metabolism; however, its underlying putative mechanism of regulating the production of indigo alkaloids is currently unknown.

RESULTS

One gene encoding EPSPS was isolated from B. cusia. Quantitative real-time PCR analysis revealed that BcEPSPS was expressed at the highest level in the stem and upregulated by methyl jasmonate (MeJA), salicylic acid (SA) and abscisic acid (ABA) treatment. The results of subcellular localization indicated that BcEPSPS is mainly expressed in both the plastids and cytosol, which has not been previously reported. An enzyme assay revealed that the heterogeneously expressed BcEPSPS protein catalysed the generation of 5-enolpyruvyl shikimate-3-phosphate. The overexpression of BcEPSPS in Isatis indigotica hairy roots resulted in the high accumulation of indigo alkaloids, such as indigo, secologanin, indole and isorhamnetin.

CONCLUSIONS

The function of BcEPSPS in catalysing the production of EPSP and regulating indigo alkaloid biosynthesis was revealed, which provided a distinct view of plant metabolic engineering. Our findings have practical implications for understanding the effect of BcEPSPS on active compound biosynthesis in B. cusia.

Deciphering the bacterial composition in the rhizosphere of Baphicacanthus cusia (NeeS) Bremek

Rhizobacteria is an important ingredient for growth and health of medicinal herbs, and synthesis of pharmacological effective substances from it. In this study, we investigated the community structure and composition of rhizobacteria in Baphicacanthus cusia (NeeS) Bremek via 16S rRNA amplicon sequencing. We obtained an average of 3,371 and 3,730 OTUs for bulk soil and rhizosphere soil samples respectively. Beta diversity analysis suggested that the bacterial community in the rhizosphere was distinctive from that in the bulk soil, which indicates that B.cusia can specifically recruit microbes from bulk soil and host in the rhizosphere. Burkholderia was significantly enriched in the rhizosphere. Burkholderia is a potentially beneficial bacteria that has been reported to play a major role in the synthesis of indigo, which was a major effective substances in B. cusia. In addition, we found that Bacilli were depleted in the rhizosphere, which are useful for biocontrol of soil-borne diseases, and this may explain the continuous cropping obstacles in B. cusia. Our results revealed the structure and composition of bacterial diversity in B. cusia rhizosphere, and provided clues for improving the medicinal value of B. cusia in the future.

Association of Gene Mutations with Response to Arsenic-Containing Compound Qinghuang Powder () in Patients with Myelodysplastic Syndromes

OBJECTIVES

To investigate the relationship between gene mutations and response to Compound Qinghuang Powder (, CQHP) in patients with myelodysplastic syndrome (MDS).

METHODS

Forty-three MDS patients were genotyped by ultra-deep targeted sequencing and the clinical data of patients were collected and the relationship between them was analyzed.

RESULTS

Up to 41.86% of patients harbored genet mutations, in most cases with more than one mutation. The most common mutations were in SF3B1, U2AF1, ASXL1, and DNMT3A. After treatment with CQHP, about 88.00% of patients no longer required blood transfusion, or needed half of prior transfusions.

CONCLUSIONS

CQHP is an effective treatment for patients with MDS, especially those with gene mutations in SF3B1, DNMT3A, U2AF1, and/or ASXL1.

Study on the Clinical Safe and Effective Methods of Arsenic-Containing Compound-Qinghuang Powder in the Treatment of Myelodysplastic Syndrome

OBJECTIVE

To establish the clinical safe and effective methods of arsenic-containing compound-Qinghuang Powder (compound-QHP) in the treatment of myelodysplastic syndrome (MDS).

METHODS

200 patients with MDS were treated with compound-QHP (daily dose of 0.1 g realgar). The blood arsenic concentrations (BACs) were detected by atomic fluorescence spectrophotometry (HF-AFS). After treatment for 1 month, the patients were randomly divided into group A and group B when the BACs were less than 20 μg/L. Daily dose of realgar was maintained in group A and it was increased to that when the BACs were more than 20 μg/L in group B. The BAC and clinical efficacy and safety in two groups were compared at the end of the treatment with compound-QHP.

RESULTS

The average BAC of group B was significantly higher than that of group A (P < 0.01). The rates of hematology improvement and reduced transfusion were significantly higher in group B than in group A (P < 0.05). The HGB, ANC, and PLT significantly increased in group B after treatment (P > 0.05).

CONCLUSIONS

Monitoring the BAC and adjusting the daily dose of realgar to increase the effective BAC and then improving efficacy without increasing the clinical toxicity are the clinical safe and effective methods in the treatment of MDS.

Stable Internal Reference Genes for Normalizing Real-Time Quantitative PCR in Baphicacanthus cusia under Hormonal Stimuli and UV Irradiation, and in Different Plant Organs

Baphicacanthus cusia (Nees) Bremek, the plant source for many kinds of drugs in traditional Chinese medicine, is widely distributed in South China, especially in Fujian. Recent studies about B. cusia mainly focus on its chemical composition and pharmacological effects, but further analysis of the plant's gene functions and expression is required to better understand the synthesis of its effective compounds. Real-time quantitative polymerase chain reaction (RT-qPCR) is a powerful method for gene expression analysis. It is necessary to select a suitable reference gene for expression normalization to ensure the accuracy of RT-qPCR results. Ten candidate reference genes were selected from the transcriptome datasets of B. cusia in this study, and the expression stability was assessed across 60 samples representing different tissues and organs under various conditions, including ultraviolet (UV) irradiation, hormonal stimuli (jasmonic acid methyl ester and abscisic acid), and in different plant organs. By employing different algorithms, such as geNorm, NormFinder, and BestKeeper, which are complementary approaches based on different statistical procedures, 18S rRNA was found to be the most stable gene under UV irradiation and hormonal stimuli, whereas ubiquitin-conjugating enzyme E2 was the best suitable gene for different plant organs. This novel study aimed to screen for suitable reference genes and corresponding primer pairs specifically designed for gene expression studies in B. cusia, in particular for RT-qPCR analyses.

Effects of active bufadienolide compounds on human cancer cells and CD4+CD25+Foxp3+ regulatory T cells in mitogen-activated human peripheral blood mononuclear cells

The growth inhibitory effects of bufadienolide compounds were investigated in two intractable cancer cells, a human glioblastoma cell line U-87 and a pancreatic cancer cell line SW1990. Among four bufadienolide compounds, a dose-dependent cytotoxicity was observed in these cancer cells after treatment with gamabufotalin and arenobufagin. The IC50 values of the two compounds were 3-5 times higher in normal peripheral blood mononuclear cells (PBMCs) than these values for both cancer cell lines. However, similar phenomena were not observed for two other bufadienolide compounds, telocinobufagin and bufalin. These results thus suggest that gamabufotalin and arenobufagin possess selective cytotoxic activity against tumor cells rather than normal cells. Moreover, a clear dose-dependent lactate dehydrogenase (LDH) release, a well-known hallmark of necrosis, was observed in both cancer cells treated with gamabufotalin, suggesting that gamabufotalin-mediated cell death is predominantly associated with a necrosis-like phenotype. Of most importance, treatment with as little as 8 ng/ml of gamabufotalin, even an almost non-toxic concentration to PBMCs, efficiently downregulated the percentages of CD4+CD25+Foxp3+ regulator T (Treg) cells in mitogen-activated PBMCs. Given that Treg cells play a critical role in tumor immunotolerance by suppressing antitumor immunity, these results suggest that gamabufotalin may serve as a promising candidate, as an adjuvant therapeutic agent by manipulating Treg cells to enhance the efficacy of conventional anticancer drugs and lessen their side-effects. These findings provide insights into the clinical application of gamabufotalin for cancer patients with glioblastoma/pancreatic cancer based on its cytocidal effect against tumor cells as well as its depletion of Treg cells.