Inhibition of ecdysone receptor (DcEcR) and ultraspiracle (DcUSP) expression in Diaphorina citri increased susceptibility to pesticides.

Diaphorina citri Kuwayama is of great concern because of its ability to transmit devastating citrus greening illness (Huanglongbing). One strategy for controlling HLB may involve limiting the spread of D. citri. Insecticides using dsRNA target genes may be a useful option to control D. citri. The ecdysone receptor (EcR) and ultraspiracle (USP) are crucial for the growth and reproduction of insects. This study identified the genes for D. citri ecdysone receptor (DcEcR) and ultraspiracle (DcUSP). According to the qPCR data, DcUSP peaked at the 5th-instar nymph stage, while DcEcR peaked at the adult stage. Females expressed DcEcR and DcUSP at much higher levels than males. RNAi was used to examine DcEcR and DcUSP function. The findings demonstrated that inhibition of DcEcR and DcUSP delayed nymph development and decreased survival and eclosion rates. dsEcR caused adults to develop deformed wings, and dsUSP caused nymphs to wither and die. Female adult ovaries developed slowly, and the females laid fewer eggs. Additionally, DcEcR and DcUSP were inhibited, increasing D. citri susceptibility to pesticides. These findings suggest that DcEcR and DcUSP are critical for D. citri development, growth, and reproduction and may serve as potential targets for D. citri management.

[Clinical Efficacy and Prognostic Factors of Newly Diagnosed Children[JP] with Burkitt Lymphoma Treated by High-Dose and Short-Course Modified LMB Regimen ± Rituximab].

OBJECTIVE: To investigate the clinical efficacy and prognostic factors of high-dose and short-course modified LMB regimen ± Rituximab in the treatment of newly diagnosed children with Burkitt lymphoma, soas to provide more reference for clinical diagnosis and treatment with follow-up. METHODS: 91 newly diagnosed children with Burkitt lymphoma treated in our hospital from January 2007 to August 2016 were chosen. High-dose and short-course modified LMB regimen were used to treat children at different risk levels- Rituximab were added in treatment of high-risk group. The clinical characteristics and efficacy of the treatment were analyzed, and the related prognostic factors were evaluated. RESULTS: The overall survival rate and event-free survival rate in 5-year with follow-up of 91 children were separately（89.27±2.69）%， （87.16±2.30）%; the event-free survival rate of patients in 5-year with follow-up in low-risk, moderate-risk and high-risk group were separately 100%，（94.51±2.97）%，（84.60±3.40）%. The event-free survival rate in 5-year with follow-up of high-risk group were significantly lower than that of moderate-risk group（P<0.05）. Univariate analysis showed that the combination of maxillofacial and central nervous system invasion, LDH >1000 U/L, proportion of bone marrow tumor cell >25%, organ involvement number >4, St. Jude stage for IV stage, early chemotherapy insensitivity and tumor lesion in mid-term evaluation were risk factor for poor prognosis in newly diagnosed children with Burkitt lymphoma（P<0.05）.Multivariate analysis showed that the combination of maxillofacial and central nervous system invasion, early chemotherapy insensitivity and tumor lesion in mid-term evaluation were the independent risk factor for poor prognosis of children with Burkitt lymphoma（P<0.05）. The EFS rate in 5-year with follow-up of high-risk children treated with chemotherapy+rituximab was significantly higher than that of chemotherapy alone（P<0.05）. CONCLUSION: High-dose and short-course modified LMB regimen in the treatment of newly diagnosed children with Burkitt lymphoma shows satisfactory clinical efficacy. The children with central nervous system involvement, early chemotherapy insensitivity and tumor lesion in mid-term evaluation show the worse prognosis, while Rituximab added is more helpful to improve the long-term prognosis for high-risk children with Burkitt lymphoma.

[Reversal Effect of Pioglitazone on Multidrug Resistance in K562/ADR Cells and Its Mechanism].

OBJECTIVE: To explore the reversal effect of pioglitazone (PIO) on multidrug resistance in K562/ADR cells and its mechanism. METHODS: The proliferation inhibition rate, half inhibition concentration (IC50) and drug-resistance reversal multipe were detected and the curve of proliferation inhibition rate was drawn by MTT assay, the transcription of PPARγ, CYP2C8 and CYP2J2 genes was detected by RT-PCR; the expression of PPARγ, CYP2C8 and CYP2J2 proteins was detected by Western blot. RESULTS: The IC50 of PIO on K562 and K562/ADR cells for 60 h was 326.7 µmol/L and 349.1 µmol/L respectively. The reversal multiple of 30 µmol/L PIO on ADR-resistance of K562/ADR cells was 6.4. After treatment of K562/ADR cells with PIO, the transcription of CYP2C8 and CYP2J2 and the protein expression of CYP2C8 and CYP2J2 significantly decreased, the transcription of PPARγ gene and the expression of PPARγ protein were not changed. CONCLUSIONS: Pioglitazone can reverse the adriamycin-resistance in K562/ADR cells that is closely related to the decrease of protein expression of CYP2C8 and CYP2J2. Pioglitazone is an effective multidrug resistance reversal agent for tumors.

[Change of Autophagic Activity of U266 Cells after Bortezomib -Resistance and Its Mechanisms].

OBJECTIVE: To explore the changes of autophagic activity after resistance of U266 cells to bortezomib (Bor) and its mechanisms. METHODS: The proliferation inhibition rate, 50% inhibitory concentration (IC50), drug-resistance coefficient, drug-resistance reversed multiple by 3-methyladenine (3-MA) in U266 and U266/Bor cells treated with Bor were detected and calculated by using MTT method, then the proliferation inhibition curve was drawed. The Western blot was used to detect the expression of LC3-I, IC3-II, p-mTOR, Beclin-1, ATG5 and ATG7 proteins. RESULTS: The Bor showed the its proliferation inhibition effect on U266 cells and U266/Bor cells, IC50 of Bor on U266 and U266/Bor cells on 24 hours were 35.7 nmol/L and 526.5 nmol/L respectively; the drug-resistance coefficient was 14.7; the drug-resistance reversed multiple by 3-MA was 2.7. The expression of LC3-II, Beclin11, ATG5 and ATG7 in U266/Bor cells was higher than that in U266 cells; after the treatment with Bor for 24 h, the expression levels of LC3-II, Beclin-1, ATG5 and ATG7 in U266 cells all decreased, as compared with levels before treatment; while the expression levels of LC3-II, Beclin-1, ATG5 and ATG7 in U266/Bor cells were higher than those before treatment. There were no significant difference of p-mTOR expression among U266, U266+Bor, U266/Bor, U266/Bor+Bor cells. CONCLUSION: The increase of autophagy closely relates with resistance of U266 cells to bortezomib, moreover with up-regulation of Beclin-1, ATG5 and ATG7 expression.