Objectives: We have analyzed the influence of Amorphophallus konjac tuber (KONJAC)
extracts on protein expression of mitochondrial in cell line SGC-7901, identified those differentially
expressed by mass spectrometry, and built a network of differentially expressed proteins using software.
This provided the basis for a study of the molecular mechanisms of the anti-gastric cancer effects.
Method: The cell viability was evaluated by cell counting kit-8. Cell apoptosis assay was used to detect
cell apoptosis. Two-dimensional gel electrophoresis and MALDI-TOF-MS analysis was applied
to identify the differentially-expressed mitochondrial protein treatment with or without KONJAC extracts.
Ingenuity Pathways Analysis (IPA) software was to analysis an interacting protein.
Result: Proliferation of SGC-7901 cells was reduced and early apoptosis increased after treatment
with KONJAC extracts. Two-dimensional gel electrophoresis and MALDI-TOF-MS analysis
showed that 682 protein spots in control group and 643 protein spots in the KONJAC extract treated
group. Twenty proteins were identified that showed 10 up-regulated and 10 down-regulated proteins
in these arrays. Bioinformatic IPA network analysis showed that ubiquitin-conjugating enzyme 2(E2)
was located in the center of the network. Thus, the inhibition of cell proliferation and promotion of
apoptosis by KONJAC extracts may be through ubiquitin conjugating enzyme-mediated mitochondrial
Conclusion: These results indicate that KONJAC extract-induced apoptosis and inhibit proliferation
in SGC-7901 cells is mediated by pathways involving in mitochondrial apoptotic, gene transcription,
cell cycle, oxidative stress response and energy metabolism. KONJAC extracts could be promising
as a treatment for gastric cancer.