Agrimoniin is a dual inhibitor of AKT and ERK pathways that inhibit pancreatic cancer cell proliferation.

Molecular-targeted therapy has shown its effectiveness in pancreatic cancer, while single-targeted drug often cannot provide long-term benefit because of drug resistance. Fortunately, multitarget combination therapy can reverse drug resistance and achieve better efficacy. The typical treatment characteristics of traditional Chinese medicine monomer on tumor are multiple targets, with small side effects, low toxicity, and so forth. Agrimoniin has been reported to be effective on some cancers, while the mechanism still needs to be clarified. In this study, we used 5-ethynyl-2'-deoxyuridine, cell counting kit-8, flow cytometry, and western blot experiments to confirm that agrimoniin can significantly inhibit the proliferation of pancreatic cancer cell PANC-1 by inducing apoptosis and cell cycle arrest. In addition, by using SC79, LY294002 (the agonist or inhibitor of AKT pathway), and U0126 (the inhibitor of ERK pathway), we found that agrimoniin inhibited cell proliferation by simultaneously inhibiting AKT and ERK pathways. Moreover, agrimoniin could significantly increase the inhibitory effect of LY294002 and U0126 on pancreatic cancer cells. Meanwhile, in vivo experiments also supported the above results. In general, agrimoniin is a double-target inhibitor of AKT and ERK pathways in pancreatic cancer cells; it is expected to be used as a resistance reversal agent of targeted drugs or a synergistic drug of the inhibitor of AKT pathway or ERK pathway.

Ophiopogonin B alleviates cisplatin resistance of lung cancer cells by inducing Caspase-1/GSDMD dependent pyroptosis.

Drug resistance has become the main reason for the failure of tumor chemotherapy. Radix Ophiopogon Japonicus has long been used as traditional Chinese medicine to treat pulmonary disease, and Ophiopogonin B (OP-B) as a bioactive component of it has also been verified to inhibit cell proliferation of various non-small cell lung cancer (NSCLC) cells in vivo and in vitro. Therefore, we wonder whether OP-B is also effective to drug resistant lung cancer cells. Firstly, Cell Counting Kit-8 (CCK8) assay was used to compare the sensitivity of OP-B on NCI-H460, A549, cisplatin resistant A549 (A549/DDP) and paclitaxel resistant A549 (A549/PTX) cells, and A549/DDP cells were shown to be more sensitive to OP-B than other three cell lines, the results were further verified in orthotopic tumor nude mice model and zebrafish tumor model. Moreover, observation of cell morphological feature, mitochondrial membrane potential, LDH release rate, and production of IL-1ß all suggested that OP-B induced pyroptosis in A549/DDP cells more significantly than that in A549 cells. Meanwhile, transcriptomic sequencing results between OP-B treated and the Mock A549/DDP group also suggested that OP-B induced more significant Caspase-1/GSDMD dependent pyroptosis in A549/DDP group, which was further verified by VX-765, the inhibitor of Caspase-1. Together, the experimental results suggested that OP-B alleviated DDP resistance of A549 cells through inducing more significant Caspase-1/GSDMD-dependent pyroptosis.

Yin Yang-1 suppresses pancreatic ductal adenocarcinoma cell proliferation and tumor growth by regulating SOX2OT-SOX2 axis.

The transcription regulator Yin Yang-1 (YY1) serves as a tumor suppressor in pancreatic ductal adenocarcinoma (PDAC). However, the function of YY1 in proliferation of PDAC cells remains to be clarified. In this study, we found that overexpression of YY1 suppressed proliferation and decreased the expression of long non-coding RNA (lncRNA) SOX2OT and its potential target gene SOX2 in PDAC cells. Luciferase reporter, electrophoretic mobility shift (EMSA), and chromatin immunoprecipitation (ChIP) assays revealed binding of YY1 to the SOX2OT promoter. Moreover, YY1 suppressed PDAC cell proliferation through SOX2OT transcriptional inhibition and subsequent decreased SOX2 expression. In addition, YY1 expression was statistically negatively correlated with SOX2OT and SOX2 expression in PDAC tissues and lower level expression of SOX2OT predicted better outcome in PDAC patients. These results confirmed the anti-proliferation effect of YY1 on PDAC cells, which was associated with SOX2 down-regulation in a SOX2OT-dependent mechanism. Although other undiscovered mechanisms may be involved in the YY1-mediated tumor suppression role, the present study suggests that SOX2OT may act as a tumor promotor in PDAC and may represent a valuable diagnostic and therapeutic target.

Transcriptional regulation of human MUC4 gene: identification of a novel inhibitory element and its nuclear binding protein.

The human mucin 4 (MUC4) is aberrantly expressed in pancreatic adenocarcinoma and tumor cell lines, while remaining undetectable in normal pancreas, indicating its important role in pancreatic cancer development. Although its transcriptional regulation has been investigated in considerable detail, some important elements remain unknown. The aim of the present study was to demonstrate the existence of a novel inhibitory element in the MUC4 promoter and characterize some of its binding proteins. By luciferase reporter assay, we located the inhibitory element between nucleotides -2530 and -2521 in the MUC4 promoter using a series of deletion and mutant reporter constructs. Electrophoretic mobility shift assay (EMSA) with Bxpc-3 cell nuclear extracts revealed that one protein or protein complex bind to this element. The proteins binding to this element were purified and identified as Yin Yang 1 (YY1) by mass spectrometry. Supershift assay and chromatin immunoprecipitation (ChIP) assay confirmed that YY1 binds to this element in vitro and in vivo. Moreover, transient YY1 overexpression significantly inhibited MUC4 promoter activity and endogenous MUC4 protein expression. In conclusion, we reported here a novel inhibitory element in the human MUC4 promoter. This provides additional data on MUC4 gene regulation and indicates that YY1 may be a potential target for abnormal MUC4 expression.

[In vitro activity of baicalin against non-albicans Candida biofilms].

OBJECTIVE: To investigate the effects of baicalin against Candida glabrata, C. parapsilosis, C. krusei and C. guilliermondii biofilms. METHOD: 96-well microtitre plates were used to set up the biofilms; microdilution method was applied to detect minimal inhibitory concentration (MIC) of baicalin for the four non-albians Candida, and XTT reduction assay was adopted to determine sessile minimal inhibitory concentration (SMIC) of baicalin against the four isolates and to detect the effects on adhesion of the fungal cells. RESULT: MICs of baicalin for the four non-albians Candida cells were 125, 250, 125, 62.5 mg L(-1), respectively. The four non-albians Candida could form mature biofilms on 96-well microtitre plates. SMIC50 of baicalin for the four isolates were > 1000, 500, 125, 250 mg x L(-1), respectively. SMIC80 for the four isolates were greater than or equal to 1000 mg x L(-1). Baicalin showed potent inhibitory effects on adhesion of the four non-albians Candida cells. CONCLUSION: Baicalin displays substantial inhibitory effects on C. parapsilosis, C. krusei and C. guilliermondii biofilm.