Amygdalin suppresses the proliferation, migration and EMT of gastric cancer cells by inhibiting TGF-β/Smad signal pathway

Purpose: To investigate the effects of amygdalin on the proliferation, motility and epithelial mesenchymal transformation (EMT) of gastric cancer cells and to elucidate the operating mechanisms of action.Methods: Gastric cancer AGS cells were treated with amygdalin (2.5, 5 and 10 mg/L). MTT and colony formation assays were used to investigate the effect of amygdalin on gastric cancer cell proliferation, while wound healing and Transwell assays were also carried out to determine its effect on the motility of gastric cancer cells. Immunoblot assays were used to investigate the effects of amygdalin on epithelial mesenchymal transformation (EMT) process and TGF-β/Smad pathway in gastric cancer cells.Results: Treatment with amygdalin suppressed the proliferation of gastric cancer AGS cells (p < 0.05). Amygdalin suppressed the migration and invasion of AGS cells in vitro (p < 0.05). Additionally, amygdalin suppressed epithelial mesenchymal transformation (EMT) in AGS cells, and suppressed TGF-β/Smad pathway (p < 0.05), thereby suppressing growth, motility, and EMT in AGS cells.Conclusion: Amygdalin may be useful for the treatment of gastric cancer; however, further studies are required ascertain this

Doppler Spread Estimation by Tracking the Delay-Subspace for OFDM Systems in Doubly Selective Fading Channels

A novel maximum Doppler spread estimation algorithm for OFDM systems with comb-type pilot pattern is presented in this paper. By tracking the drifting delay subspace of time-varying multipath channels, a Doppler dependent parameter can be accurately measured and further expanded and transformed into a non-linear high-order polynomial equation, from which the maximum Doppler spread is readily solved by resorting to the Newton's method. Its performance is demonstrated by simulations.Comment: 4 pages, 2 figures, Appear in IEEE Signal Process. Letter

ARHI (DIRAS 3), an Imprinted Tumor Suppressor Gene, Binds to Importins, and Blocks Nuclear Translocation of Stat3

ARHI (DIRAS3) is an imprinted tumor suppressor gene whose expression is lost in the majority of breast and ovarian cancers. Unlike its homologs Ras and Rap, ARHI functions as a tumor suppressor. Our previous study showed that ARHI can interact with transcription activator Stat3 and inhibit its nuclear translocation in human breast and ovarian cancer cells. To identify proteins that interact with ARHI in nuclear translocation, we have performed proteomic analysis and identified several importins that can associate with ARHI. To further explore this novel finding, we have purified 10 GST-importin fusion proteins (importin 7, 8, 13, b1, a1, a3, a5, a6, a7 as well as mutant a1). Using a GST-pull down assay, we found that ARHI can bind strongly to most importins; however, its binding is significantly reduced with an importin a1 mutant which contains an altered nuclear localization signal (NLS) domain. In addition, an ARHI N-terminal deletion mutant (NTD) exhibits much less binding to all importins than does wild type ARHI ARHI and NTD proteins were purified and tested for their ability to inhibit nuclear importation of proteins in HeLa cells. ARHI protein inhibits interaction of Ran-importin complexes with GFP fusion proteins that contain an NLS domain and a beta-like import receptor binding domain, blocking their nuclear localization. Addition of ARHI also blocked nuclear localization of phosphorylated Stat3β. By GST-pull down assays, we found that ARHI could compete for Ran-importins binding. Thus, ARHI-induced disruption of importin binding to cargo proteins including Stat3 could serve as an important regulatory mechanism that contributes to the tumor suppressor function of ARHI