Synergistic combination of DT-13 and Topotecan inhibits aerobic glycolysis in human gastric carcinoma BGC-823 cells via NM IIA/EGFR/HK II axis.

DT-13 combined with topotecan (TPT) showed stronger antitumour effects in mice subcutaneous xenograft model compared with their individual effects in our previous research. Here, we further observed the synergistically effect in mice orthotopic xenograft model. Metabolomics analysis showed DT-13 combined with TPT alleviated metabolic disorders induced by tumour and synergistically inhibited the activity of the aerobic glycolysis-related enzymes in vivo and in vitro. Mechanistic studies revealed that the combination treatment promoted epidermal growth factor receptor (EGFR) degradation through non-muscle myosin IIA (NM IIA)-induced endocytosis of EGFR, further inhibited the activity of hexokinase II (HK II), and eventually promoted the aerobic glycolysis inhibition activity more efficiently compared with TPT or DT-13 monotherapy. The combination therapy also inhibited the specific binding of HK II to mitochondria. When using the NM II inhibitor (-)002Dblebbistatin or MYH-9 shRNA, the synergistic inhibition effect of DT-13 and TPT on aerobic glycolysis was eliminated in BGC-823 cells. Immunohistochemical analysis revealed selective up-regulation of NM IIA while specific down-regulation of p-CREB, EGFR, and HK II by the combination therapy. Collectively, these findings suggested that this regimen has significant clinical implications, warranted further investigation.

Synergistic combination of DT-13 and topotecan inhibits human gastric cancer via myosin IIA-induced endocytosis of EGF receptor in vitro and in vivo.

Combination therapy has a higher success rate for many cancers compared to mono-therapy. The treatment of Topotecan (TPT) on gastric cancer (GC) is limited by its toxicity and the potential drug resistance. We found that the combination of the saponin monomer 13 from the dwarf lilyturf tuber (DT-13), performing anti-metastasis and anti-angiogenesis effects, with TPT synergistically induced apoptotic cytotoxicity in GCs with high EGF receptor (EGFR) expression, which was dependent on DT-13-induced endocytosis of EGFR. With TPT, DT-13 promoted EGFR ubiquitin--mediated degradation through myosin IIA-induced and Src/ caveolin-1 (Cav-1)-induced endocytosis of EGFR; inhibited EGFR downstream signalling and then increased the pro-apoptotic effects. Moreover, the synergistic pro-apoptotic efficacy of DT-13 and TPT in GCs with high EGFR expression was eliminated by both the NM II inhibitor (-)-blebbistatin and MYH-9 shRNA. The combination therapy of DT-13 with TPT showed stronger anti-tumour effects in vivo compared with their individual effects. Moreover, the results of combination therapy revealed selective upregulation of pro-apoptotic activity in TUNEL assays and cleaved caspase-3 and NM IIA in immunohischemical analysis; while specific downregulation of p-extracellular regulated kinase 1/2 (p-ERK1/2), EGFR and Cav-1 in immunohischemical analysis. Collectively, these findings have significant clinical implications for patients with tumours harbouring high EGFR expression due to the possible high sensitivity of this regimen.

[Identification of some Piper crude drugs based on Fourier transform infrared spectrometry].

The common peak ratio and variant peak ratio were calculated by FTIR spectroscopy of seven medicinal plants of Piper. The dual index sequence of common peak ratio and variant peak ratio was established, which showed the sibship of the medicinal plants. The common peak ratio of Piper kadsura (Choisy) Ohwi, Piper wallichii (Miq.) Hand.-Mazz. Piper laetispicum (C. DC.) was greater than 77%, and the variant peak ratio was less than 30%. The results showed the near sibship between the three drugs. The common peak ratio of Piper kadsura (Choisy) Ohwi, Piper nigrum L. and Piper boehmeriae folium Wall (Miq.) C. DC. Var. tonkinense (C. DC.) was about 61% which showed the farther sibship. The common peak ratio of Piper kadsura (Choisy) Ohwi and Piper betle (Linn.) was only 44%, which showed the farthest sibship. Piper kadsura (choisy) Ohwi and its adulterants, such as Piper wallichii (Miq.) Hand. -Mazz., Piper boehmeriaefolium Wall (Miq.) C. DC. Var. tonkinense C. DC. , Piper laetispicum C. DC., Piper nigrum L., could be identified by comparing their second order derivative IR spectrum of the samples. FTIR technique is a non-destructive analysis method which provides information of functional group, type and hydrogen bond without complex pretreatment procedures such as extraction and separatioin. FTIR method has some characteristics such as rapid and simple analysis procedure, good reproducibility, non-destructive testing, few amount of required sample and low cost and is environment-friendly. The method solved the problems of limit in resource of Piper kadsura (Choisy) Ohwi, many fakes and difficulties in identification, and brought the security for the clinical medication. FTIR provides a new method for identification of Piper kadsura (choisy) Ohwi and its fakes and meets the requirement for comprehensive analy sis and global analysis of traditional Chinese medicine.

Application of ionic liquids in the microwave-assisted extraction of polyphenolic compounds from medicinal plants.

Ionic liquids (ILs) solutions as solvents were successfully applied in the microwave-assisted extraction (MAE) of polyphenolic compounds from medicinal plants. ILs, its concentration and MAE conditions were investigated in order to extract polyphenolic compounds effectively from Psidium guajava Linn. (P. guajava) leaves and Smilax china (S. china) tubers. The results obtained indicated that the anions and cations of ILs had influences on the extraction of polyphenolic compounds as well as the ILs with electron-rich aromatic pi-system enhanced extraction ability. Under the optimized conditions, the extraction yields of the polyphenolic compounds were in the range of 79.5-93.8% with one-step extraction, and meanwhile the recoveries were in the range of 85.2-103% with relative standard deviations (R.S.D.s) lower than 5.6%. Compared to conventional extraction procedures, the results suggested that the proposed method was effective and alternative for the extraction of polyphenolic compounds from medicinal plants. In addition, the extraction mechanisms and the structures of samples before and after extraction were also investigated. ILs solutions as green solvents in the MAE of polyphenolic compounds from medicinal plant samples showed a great promising prospect.