Epigallocatechin gallate inhibits the proliferation and induces apoptosis of multiple myeloma cells via inactivating EZH2

OBJECTIVE

Epigallocatechin gallate (EGCG), the major chemical constituent of green tea, exhibits remarkable anti-tumor effect properties. In the present work, we aim to explore the effect and underlying mechanism of EGCG on multiple myeloma (MM) cells.

MATERIALS AND METHODS

The effects of EGCG on MM cells proliferation and apoptosis were determined by CCK-8 assay and flow cytometry assay. The siRNAs were used to inhibit endogenous expression of EZH2. Enforced expression of EZH2 in U266 cells was accomplished by transfecting EZH2 plasmid.

RESULTS

EGCG suppressed proliferation and induced apoptosis in U266 cells, which accompanied by EZH2 inhibition. Moreover, we revealed that enforced expression of EZH2 increased MM cells proliferation and reduced cell apoptosis, whereas EGCG partially reversed the effects of EZH2 on MM cells progression. In addition, qRT-PCR and Western blot showed that EZH2 overexpression increased Bcl-2 expression, and decreased BAX, BAK1 and cytochrome c expression in U266 cells exposed to EGCG.

CONCLUSIONS

Our data showed that EGCG inhibited MM cells proliferation and induced apoptosis by targeting EZH2 and modulated mitochondrial apoptosis pathway, indicating EGCG might act as an adjuvant for chemotherapy of MM patients.

Risk factors contributing to early and late recurrence of haemoptysis after bronchial artery embolisation

OBJECTIVE

To identify the risk factors for early and late relapse of haemoptysis after bronchial artery embolisation (BAE).

DESIGN

We performed a retrospective study of 255 patients with haemoptysis who underwent BAE from January 2009 to June 2016 at the First Affiliated Hospital of Nanjing Medical University, Nanjing, China. Using a Cox regression model, risk factors contributing to early (within the first month) and late (>1 month) recurrence were analysed. We censored recurrence-free patients at 1 month and patients without rebleeding after 1 month.

RESULTS

The cumulative recurrence rate at 1, 6, 12, 24 and 48 months was respectively 14.9%, 16.9%, 20.6%, 31.0% and 39.9%, with a median follow-up of 574 days. Early relapse occurred in 38 of 255 patients, while late recurrence was found in 45 of the remaining 217 patients. The risk factors related to early recurrence were lung destruction on computed tomography of the chest and involvement of non-bronchial systemic arteries. The risk factors associated with late recurrence were tuberculosis sequelae, the presence of shunts and the use of gelfoam as an embolisation material.

CONCLUSIONS

The variables related to incomplete embolisation were the risk factors for early rebleeding. The variables associated with same-vessel recanalisation and formation of a new collateral circulation influenced late recurrence.

Embolisation for life-threatening haemoptysis complicated by systemic artery-pulmonary circulation shunts

SETTING

Tertiary referral centre.

OBJECTIVE

To retrospectively observe the characteristics of bronchial angiograms in the setting of systemic artery-pulmonary circulation shunts (SPS), and to evaluate the safety and effectiveness of bronchial artery embolisation (BAE) for these patients with life-threatening haemoptysis.

DESIGN

The records of life-threatening haemoptysis patients with SPS who presented to a tertiary referral centre from January 2009 to March 2014 were reviewed.

RESULTS

SPS consisted of bronchial artery-pulmonary artery shunt (AAS) in 30 cases, bronchial artery-pulmonary vein shunt (AVS) in 4 cases, non-bronchial systemic artery-pulmonary circulation shunt (n-BPS) in 7 cases and more than one type of SPS in 4 cases (AAS and AVS in 3 cases, three types of SPS in 1 case). BAE using polyvinyl alcohol (PVA) was successful in 97.8% (44/45) of the patients. Cumulative rates of freedom from recurrence at 1 month, 1 year and 2 years were respectively 97.8%, 93.2% and 85.4%. No major procedure-related complications occurred. No significant differences were found in recurrence rates or cumulative haemoptysis control rates among patients with different types of SPS complications (P = 0.55 and 0.46, respectively).

CONCLUSION

BAE with PVA was safe and effective for life-threatening haemoptysis complicated by SPS.

Removal of methyl blue from aqueous solution by magnetic carbon nanotube

Magnetic carbon nanotube (mCNT) was formed via direct mixing of carbon nanotube (CNT) with magnetic nanoparticle (MNP) in dye solution. When the mass ratio of MNP to CNT was 4:1, all CNT were magnetically collected. The adsorption performance of mCNT was evaluated using methyl blue (MB) as a model adsorbate. Equilibrium of MB adsorption was attained in 60 min, and maximum adsorption occurred at pH 3-6. MB adsorption was independent of ionic strength and followed pseudo-second-order kinetics. According to the Langmuir isotherm, adsorption capacity of mCNT for MB was 115.34 mg g(-1). Thermodynamic analysis suggested MB adsorption onto mCNT was a spontaneous process. Reusability study results showed that 97.06, 96.26, 94.33, 92.91 and 90.14% of MB were removed in five consecutive cycles. The study suggests that the mCNT has a great potential application in dye removal from industrial wastewater.

[Effects of oxygen radical scavengers on the output of 3-methylhistidine in urine after severe burns]

Burned rats (30% TBSA III) were divided into two groups at random: animals of group A receiving I. M. injection of bovine serum albumin served as control; group B, the treated group, received I.M. injection of superoxide dismutase (SOD) and catalase (CAT). The urine of these animals collected respectively on PBD 5,7,9,11, was analysed according to the improved program on the 121-MB Amino Acid Analyzer (Beckman) after acidolysis. It was found that on PBD 5,7,9,11 urinary 3-Mehis excretion was significantly lower in group B than that in group A (P less than 0.01). It suggested that probably a certain relationship existed between lipoperoxide and increased protein catabolism after severe burns. SOD and CAT, the oxygen radical scavengers could reduce protein catabolism to a certain extent.