[Antitumor Effect of Dihydroartemisinin on Diffuse Large B-Cell Lymphoma].

OBJECTIVE: To investigate the potential antitumor effect and its mechanism of dihydroartemisinin (DHA) on diffuse large B-cell lymphoma (DLBCL). METHODS: OCI-Ly7 cells were respectively treated with different concentrations of DHA (0, 12.5, 25, 50 and 100 µmol/L) , CCK-8 was used to detect the cells viability. Subsequently, OCI-Ly7 cells were divided into 5 groups : DHA 0,25,50,100 µmol / L and DHA (100 µmol / L) + Colivelin (STAT3 activator). Aldehyde dehydrogenase (ALDH) positive cells were sorted by flow cytometry, the sphere-forming ability of stem cells was detected. Transwell assay and scratch test were used to analyze the invasion and migration of cells. Western blot was used to detect the expression of migration and invasion-related proteins, as well as the phosphorylation levels of Janus kinase 2 (JAK2) and signal transducer and activator of transcription 3(STAT3). RESULTS: DHA induced obvious cytotoxicity to OCI-Ly7 cells. Compared with the control group, the stem cell-like properties, invasion and migration of OCI-Ly7 were significantly inhibited in DHA 50 µmol/L group and 100 µmol/L group, while the phosphorylation levels of JAK2 and STAT3 were significantly reduced. There was no significant difference in DHA 25 µmol/L group compared with the control group. Treated with Colivelin, the inhibition of DHA on OCI-Ly7 stem cell-like properties, invasion and migration was significantly reversed, and the expression of p-STAT3 was significantly up-regulated. CONCLUSION: DHA has antitumor effect on DLBCL, and its mechanism may be through inhibiting the activation of JAK2/STAT3 pathway to inhibit the stem cell-like properties, invasion and migration of DLBCL cells.

Chondroprotective Effects of Gubitong Recipe via Inhibiting Excessive Mitophagy of Chondrocytes.

Objective: Osteoarthritis (OA) is the most common degenerative joint disorder and a leading cause of disability. A previous randomized controlled trial has shown that Gubitong (GBT) recipe can improve OA-related symptoms and articular function without noticeable side effects. However, the underlying mechanisms remain unclear. This study aims to explore the therapeutic mechanisms of the GBT recipe for OA through in vivo and in vitro experiments. Methods: Rats of the OA model were established by Hulth surgery and intervened with the GBT recipe and then were subjected to pathological assessment of the cartilage. Matrix metalloproteinase 13 (MMP-13) expression in cartilage tissues was assessed by immunohistochemical staining. Chondrocytes were isolated from sucking rats and stimulated with LPS to establish an in vitro model. After intervened by water extraction of the GBT recipe, the fluorescent signal of Mtphagy Dye and mitochondrial membrane potential (Δψm) were detected to determine the states of mitophagy and mitochondrial dynamics of chondrocytes in vitro, respectively. Western blot test was used to detect levels of proteins related to catabolism of the cartilage matrix, mitophagy, and PI3K/AKT pathway. Results: In in vivo experiments, the GBT recipe can effectively inhibit the cartilage degeneration of chondrocytes in OA rats, as well as markedly suppress the expression of MMP-13. In vitro experiments on LPS-induced chondrocytes exhibited increase in mitochondrial depolarization and excessive mitophagy, and the GBT recipe can alleviate these changes. LPS-stimulated chondrocytes showed increases in MMP-13, PINK1, and Parkin in cell lysates and LC3II/LC3I ratio in the mitochondrial fraction, and the GBT recipe can inhibit these increases in a dose-dependent manner. Moreover, the GBT recipe can attenuate the abnormal activation of PI3K/AKT pathway induced by LPS. Conclusion: The GBT recipe exhibits chondroprotective effects through inhibiting excessive mitophagy of chondrocytes, which may be associated with its inhibitory effect on the abnormal activation of PI3K/AKT pathway.

The Long Noncoding RNA MEG3 Retains Epithelial-Mesenchymal Transition by Sponging miR-146b-5p to Regulate SLFN5 Expression in Breast Cancer Cells.

More and more studies have shown that long noncoding RNAs (lncRNAs) play essential roles in malignant tumors. The lncRNA MEG3 serves as a crucial molecule in breast cancer development, but the specific molecular mechanism needs to be further explored. We previously reported that Schlafen family member 5 (SLFN5) inhibits breast cancer malignant development by regulating epithelial-mesenchymal transition (EMT), invasion, and proliferation/apoptosis. Herein, we demonstrated that MEG3 was downregulated in pan-cancers and correlated with SLFN5 expression positively in breast cancer by bioinformatics analysis of TCGA and UCSC Xena data. Intervention with MEG3 positively affected SLFN5 expression in breast cancer cells. MEG3 repressed EMT and migration/invasion, similar to our previously reported functions of SLFN5 in breast cancer. Through bioinformatics analysis of starBase and LncBase data, 12 miRNAs were found to regulate both SLFN5 and MEG3, in which miR-146b-5p was confirmed to be regulated by MEG3 using MEG3 siRNA and overexpression method. MiR-146b-5p could bind to both SLFN5 3'UTR and MEG3, and inhibit their expression in a competing endogenous RNA mechanism, assayed by luciferase reporter and RNA pull down methods. Therefore, we conclude that MEG3 positively modulates SLFN5 expression by sponging miR-146b-5p and inhibits breast cancer development.

Multiple Mechanistic Models Reveal the Neuroprotective Effects of Diterpene Ginkgolides against Astrocyte-Mediated Demyelination via the PAF-PAFR Pathway.

Currently, therapies for ischemic stroke are limited. Ginkgolides, unique Folium Ginkgo components, have potential benefits for ischemic stroke patients, but there is little evidence that ginkgolides improve neurological function in these patients. Clinical studies have confirmed the neurological improvement efficacy of diterpene ginkgolides meglumine injection (DGMI), an extract of Ginkgo biloba containing ginkgolides A (GA), B (GB), and K (GK), in ischemic stroke patients. In the present study, we performed transcriptome analyses using RNA-seq and explored the potential mechanism of ginkgolides in seven in vitro cell models that mimic pathological stroke processes. Transcriptome analyses revealed that the ginkgolides had potential antiplatelet properties and neuroprotective activities in the nervous system. Specifically, human umbilical vein endothelial cells (HUVEC-T1 cells) showed the strongest response to DGMI and U251 human glioma cells ranked next. The results of pathway enrichment analysis via gene set enrichment analysis (GSEA) showed that the neuroprotective activities of DGMI and its monomers in the U251 cell model were related to their regulation of the sphingolipid and neurotrophin signaling pathways. We next verified these in vitro findings in an in vivo cuprizone (CPZ, bis(cyclohexanone)oxaldihydrazone)-induced model. GB and GK protected against demyelination in the corpus callosum (CC) and promoted oligodendrocyte regeneration in CPZ-fed mice. Moreover, GB and GK antagonized platelet-activating factor (PAF) receptor (PAFR) expression in astrocytes, inhibited PAF-induced inflammatory responses, and promoted brain-derived neurotrophic factor (BDNF) and ciliary neurotrophic factor (CNTF) secretion, supporting remyelination. These findings are critical for developing therapies that promote remyelination and prevent stroke progression.

Augmenter of liver regeneration protects the kidney against ischemia-reperfusion injury by inhibiting necroptosis.

Necroptosis plays an important role in the pathogenesis of acute kidney injury (AKI), and necroptosis-related interventions may therefore be an important measure for the treatment of AKI. Our previous study has shown that augmenter of liver regeneration (ALR) inhibits renal tubular epithelial cell apoptosis and regulates autophagy; however, the influence of ALR on necroptosis remains unclear. In this study, we investigated the effect of ALR on necroptosis caused by ischemia-reperfusion and the underlying mechanism. In vivo experiments indicated that kidney-specific knockout of ALR aggravated the renal dysfunction and pathological damage induced by ischemia-reperfusion. Simultaneously, the expression of renal necroptosis-associated protein receptor-interacting protein 1 (RIP1), receptor-interacting protein 3 (RIP3), and mixed-lineage kinase domain-like protein (MLKL) significantly increased. In vitro experiments indicated that overexpression of ALR decreased the expression of hypoxia-reoxygenation-induced kidney injury molecules, the inflammation-associated factor tumor necrosis factor-alpha (TNF-α), and monocyte chemotactic protein. Additionally, the expression of RIP1, RIP3, and MLKL, which are elevated after hypoxia and reoxygenation, was also inhibited by ALR overexpression. Both in vivo and in vitro results indicated that ALR has a protective effect against acute kidney injury caused by ischemia-reperfusion, and the RIP1/RIP3/MLKL pathway should be further verified as a probable necroptosis regulating mechanism.

Human Schlafen 5 Inhibits Proliferation and Promotes Apoptosis in Lung Adenocarcinoma via the PTEN/PI3K/AKT/mTOR Pathway.

BACKGROUND: Human Schlafen 5 (SLFN5) is reported to inhibit or promote the proliferation of several specific types of cancer cells by our lab and other researchers. We are curious about its implications in lung adenocarcinoma (LUAC), a malignant tumor with a high incidence rate and high mortality. METHOD: Lentiviral stable transfections of SLFN5-specific shRNA for knockdown and SLFN5 full-length coding sequence for overexpression were performed in LUAC cell for proliferation analysis in vitro and in vivo in nude mice. Clinical LUAC samples were collected for immunohistochemical analysis of SLFN5 protein levels. RESULTS: We found that knockdown of endogenous SLFN5 upregulates cancer cell proliferation while inhibiting apoptosis. Besides, SLFN5 inhibition on proliferation was also observed in a nude mouse xenograft model. In contrast, overexpression of exogenous SLFN5 inhibited cell proliferation in vitro and in vivo and promoted apoptosis. As to the signaling pathway, we found phosphatase and tensin homolog on chromosome 10 (PTEN) was positively regulated by SLFN5, while its downstream signaling pathway AKT/mammalian target of rapamycin (mTOR) was inhibited. Moreover, compared with adjacent normal tissues, SLFN5 protein levels were markedly decreased in lung adenocarcinoma tissues. In conclusion, these suggest that human SLFN5 plays inhibitory roles in LUAC progression through the PTEN/PI3K/AKT/mTOR pathway, providing a potential target for developing drugs for lung cancer therapy in the future.

Prognostic value of TP53 co-mutation status combined with EGFR mutation in patients with lung adenocarcinoma.

PURPOSE: TP53/EGFR co-mutation has been reported to affect the efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) in lung adenocarcinoma (LUAD). However, its impact on survival is unclear. In this analysis, we explored the prognostic effect of TP53/EGFR co-mutation in LUAD. METHODS: Clinical data and transcriptome sequencing of LUAD patients with matched genomic data were downloaded from the Cancer Genome Atlas (TCGA) database for overall survival (OS) analysis. Differential expression genes (DEGs) were recognized by R software and bioconductor package. Clusterprofiler was used for functional analysis. STRING was used for estimating PPI information and plug-in CytoHubba to screen hub modules in Cytoscape. The association between tumor mutation burden (TMB) and survival was also analyzed. RESULTS: OS was shorter for patients carrying TP53 mutation (MUT) than that of wild type (WT) (37.7 m vs 52.8 m; p = 0.040, HR = 1.38, 95% CI 1.01-1.89). Dual TP53/EGFR-MUT was associated with inferior OS compared with the dual WT/WT cohort (38.4 m vs 51.9 m; p = 0.023, HR 1.83, 95% CI 0.95-3.52). 316 DEGs between dual TP53/EGFR-MUT and dual WT/WT samples were obtained and functional analysis made known that DEGs were strikingly enriched in regulating the metabolism of important amino acids, cell division, cell cycle regulation, cell adhesion, and extracellular matrix composition. KEGG analysis discovered that DEGs were mainly enriched in signaling pathways such as PI3K-Akt, cytokine-cytokine receptor interaction, focal adhesions, and extracellular matrix receptor interaction. PPI network suggested that GPC3, CCL28, GPR37, and NPY genes were up-regulated in dual mutation samples. OS in the high TMB cohort was significantly better than that in the low TMB in patients with TP53 MUT(43.2 m vs 32.4 m; P = 0.007, HR = 0.52, 95% CI: 0.34-0.81), as well as in the combination of TP53 MUT and EGFR WT group (44.4 m vs 31.2 m; P = 0.021, HR = 0.55, 95% CI 0.34 - 0.89). CONCLUSIONS: TP53 MUT is a poor prognostic factor in LUAD patients, and the prognosis of TP53/EGFR co-mutation is worse. GPC3, CCL28, GPR37, and NPY may be novel prognostic markers and potential therapeutic targets for patients with dual TP53/EGFR mutation LUAD.

A retrospective study comparing D1 limited lymph node dissection and D2 extended lymph node dissection for N3 gastric cancer.

BACKGROUND: In countries in East Asia, the typical treatment for curable gastric cancer is gastrectomy with D2 lymphadenectomy. However, whether D2 lymphadenectomy is beneficial for high-risk N3 node disease remains controversial. We conducted a multi-institution retrospective study on patients with high-risk, locally advanced gastric cancer. To compare the rates of disease-free survival (DFS) and overall survival (OS) between radical D2-type gastric resection and lymphadenectomy and the more limited D1 type resection and lymphadenectomy. METHODS: From July 2010 to June 2015, 74 patients out of 949 who underwent curative-intent R0 surgery were selected in pairs to compare the survival outcomes between those who underwent radical D2 type (n=37) vs. the more limited D1 type (n=37) gastric resection and lymphadenectomy. RESULTS: The median DFS was 9.72 and 7.81 months for the D2 and D1 types, respectively (P=0.746), and the OS was 16.39 and 15.85 months for the D2 and D1 types, respectively (P=0.937). CONCLUSIONS: No statistically significant differences in DFS and OS were noted between D1 and D2 procedures for those with N3 disease. Our results support the hypothesis that a novel multidisciplinary approach rather than a surgical approach alone is needed to improve the survival outcomes of high-risk patients with N3 gastric cancer.

Co-occurring genetic alterations predict distant metastasis and poor efficacy of first-line EGFR-TKIs in EGFR-mutant NSCLC.

PURPOSE: To determine the frequency of co-occurring genes in non-small cell lung cancer (NSCLC) patients with epidermal growth factor receptor (EGFR) mutation and the predictive effect of co-mutations on the efficacy of EGFR tyrosine kinase inhibitors (EGFR-TKIs). METHODS: 54 patients with advanced NSCLC were tested for 422 clinically relevant genes by next-generation sequencing (NGS) before treatment. Among them, patients with EGFR mutation received first-line treatment of EGFR-TKIs. Progression-free survival (PFS) and objective response rate (ORR) were evaluated using Kaplan-Meier methods and compared between two groups using log-rank test. RESULTS: Among 24 EGFR mutant and 30 EGFR wild-type patients, co-mutation rate was lower in patients with EGFR mutation (62.5% [15/24] vs 93.3% [28/30], p = 0.005). There was lower frequency for co-alterations in BRAF (0% [0/24] vs 20% [7/30], p = 0.033), NF1 (4.2% [1/24] vs 30% [9/30], p = 0.038) and RAS-RAF-MAPK pathway genes (16.6% [4/24] vs 56.7% [17/30], p = 0.003) in EGFR mutation group. 24 patients with EGFR mutation received first-line treatment of gefitinib or erlotinib, with an ORR of 83.3% and a median PFS of 12.3 months (95% CI 10.00-14.60). Co-mutation was associated with shorter median PFS (10.2 months [95% CI 5.20-15.20] vs 15.3 months [95% CI 12.09-15.81]; HR 0.29 [95% CI 0.10-0.82]; p = 0.014) in EGFR mutation cohort. Among patients with EGFR mutation and distant metastasis, median PFS was decreased in those with co-mutations (6.3 months [95% CI 3.25-9.35] vs 22.0 months[95% CI 12.10-31.90]; HR 0.12 [95% CI 0.00-5.87]; p = 0.007) and frequency of PIK3CA (0% [0/12] vs 41.7% [5/12], p = 0.037) and PI3K/AKT/mTOR pathway genes (0% [0/12] vs 50% [6/12], p = 0.014) was lower. CONCLUSION: The presence of co-mutations was lower in the EGFR mutation patients and reduces the efficacy of EGFR-TKI, especially in patients with distant metastases. Lower frequency of co-mutation in PIK3CA and PI3K/AKT/mTOR pathway genes may be responsible for promoting metastasis and limiting the efficacy of EGFR-TKIs.

SLFN5 suppresses cancer cell migration and invasion by inhibiting MT1-MMP expression via AKT/GSK-3ß/ß-catenin pathway.

Human SLFN5 inhibits invasions of IFNα-sensitive renal clear-cell carcinoma and melanoma cells. However, whether this inhibition is confined to these IFNα-sensitive cancers is unclear. Here we show that SLFN5 expressions on both mRNA and protein levels are significantly higher in non/low-invasive cancer cell lines (breast cancer cell line MCF7, colorectal cancer cell line HCT116 and lung cancer cell line A549) than in highly-invasive cancer cell lines (fibrosarcoma cell line HT1080 and renal clear cell cancer cell line 786-0). SLFN5 knockdown in non/low-invasive cancer cell lines enhanced MT1-MMP expression and increased migration and invasion in vitro, and in vivo. Furthermore, SLFN5 overexpression in HT1080 and 786-0 inhibited MT1-MMP expression and repressed migration and invasion. MT1-MMP is instrumental in SLFN5-controlled inhibition of cancer cell migration and invasion, as shown by MT1-MMP-knockdown and -overexpression analyses. SLFN5 knockdown activated AKT/GSK-3ß/ß-catenin pathway by promotion AKT phosphorylation and subsequent GSK-3ß phosphorylation, further ß-catenin translocation into nucleus as un-phosphorylated protein at Ser33, 37 and 45 and Thr41 sites. This is the first study to report that SLFN5 inhibits cancer migration and invasiveness in several common cancer cell lines by repressing MT1-MMP expression via the AKT/GSK-3ß/ß-catenin signalling pathway, suggesting that SLFN5 plays wide inhibitory roles in various cancers.

Saponins from Panax japonicus attenuate age-related neuroinflammation via regulation of the mitogen-activated protein kinase and nuclear factor kappa B signaling pathways.

Neuroinflammation is recognized as an important pathogenic factor for aging and related cognitive disorders. Mitogen-activated protein kinase and nuclear factor kappa B signaling pathways may mediate neuroinflammation. Saponins from Panax japonicus are the most abundant and bioactive members in rhizomes of Panax japonicus, and show anti-inflammatory activity. However, it is not known whether saponin from Panax japonicus has an anti-inflammatory effect in the aging brain, and likewise its underlying mechanisms. Sprague-Dawley rats were divided into control groups (3-, 9-, 15-, and 24-month-old groups) and saponins from Panax japonicus-treated groups. Saponins from Panax japonicus-treated groups were orally administrated saponins from Panax japonicus at three doses of 10, 30, and 60 mg/kg once daily for 6 months until the rats were 24 months old. Immunohistochemical staining and western blot assay results demonstrated that many microglia were activated in 24-month-old rats compared with 3- and 9-month-old rats. Expression of interleukin-1ß, tumor necrosis factor-α, cyclooxygenase-2, and inducible nitric oxide synthase increased. Each dose of saponins from Panax japonicus visibly suppressed microglial activation in the aging rat brain, and inhibited expression levels of the above factors. Each dose of saponins from Panax japonicus markedly diminished levels of nuclear factor kappa B, IκBα, extracellular signal-regulated kinase, c-Jun N-terminal kinase, and p38. These results confirm that saponins from Panax japonicus can mitigate neuroinflammation in the aging rat brain by inhibition of the mitogen-activated protein kinase and nuclear factor kappa B signaling pathways.

MT2-MMP induces proteolysis and leads to EMT in carcinomas.

Epithelial-mesenchymal transition (EMT) is critical for carcinoma invasiveness and metastasis. To investigate the role of membrane-type-2 matrix metalloproteinase (MT2-MMP) in EMT, we generated lentiviral constructs of wild-type (WT) and an inactive Glu260Ala (E260A) mutant MT2-MMP and derived stably transfected HCT116 and A549 cell lines. WT-transfected cells appeared mesenchymal-like, whereas cells transfected with the E260A mutant were epithelial-like, as were cells treated with an MMP inhibitor (GM6001). Expression of E-cadherin, ß-catenin, and zonula occludens-1 was lower in cells transfected with WT MT2-MMP compared to vector controls, cells treated with GM6001, or cells transfected with the E260A mutant. An 80-kD N-terminal fragment of E-cadherin was immunoprecipitated in conditioned medium from WT MT2-MMP cells, but not in the medium from vector controls, cells treated with GM6001, or E260A mutant cells. When endogenous expression of MT2-MMP in A2780 human ovarian cancer cells was inhibited using GM6001 or MT2-MMP-specific siRNA, levels of the 80-kD E-cadherin fragment in conditioned medium were decreased. Chick embryo chorioallantoic membrane invasion assays demonstrated that cells transfected with WT MT2-MMP were more invasive than cells transfected with control vector, treated with GM6001, or transfected with the E260A mutant. These results suggest that MT2-MMP degrades adherens and tight junction proteins and results in EMT, making it a potential mediator of EMT in carcinomas.

Schedule-dependent cytotoxicity of sunitinib and TRAIL in human non-small cell lung cancer cells with or without EGFR and KRAS mutations.

BACKGROUND: Non-small cell lung cancer (NSCLC) patients who do initially respond to epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) may eventually develop resistance, which may at least partly be due to the acquisition of a secondary EGFR mutation (T790M). Additionally, it has been found that KRAS mutations may serve as poor prognostic biomarkers. Here, we aimed at establishing a suitable treatment regimen for the multi-target TKI sunitinib and the tumor necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL) in NSCLC-derived cells with or without EGFR and KRAS mutations. METHODS: Four NSCLC-derived cell lines with or without EGFR and KRAS mutations were exposed to different sunitinib and TRAIL treatment regimens. Alterations in cell viability, cell cycle distribution, apoptosis, phosphorylation of AKT and expression of the death receptors DR4 and DR5 were evaluated using CCK8, flow cytometry and Western blotting assays, respectively. RESULTS: A synergistic cytotoxic effect was observed in all four cell lines treated with sunitinib (1 nM) followed by TRAIL (100 ng/ml), as well as after simultaneous treatment with both agents. We found that sunitinib enhances TRAIL-induced G0/G1-phase cell cycle arrest and blocks TRAIL-triggered activation of AKT as the underlying mechanism. In contrast, we observed antagonistic effects when sunitinib was administered after TRAIL to the cell lines tested. A decreased DR4 and DR5 expression was found to be correlated with this antagonism. CONCLUSION: From our data we conclude that administration of sunitinib followed by TRAIL, as well as a simultaneous administration of both agents, serve as favorable treatment regimens for NSCLC-derived cells, irrespective of their EGFR and/or KRAS mutation status.

Chikusetsusaponin V attenuates lipopolysaccharide-induced liver injury in mice.

Chikusetsusaponin V (CsV), a saponin from Panax japonicus, has been reported to inhibit inflammatory responses in lipopolysaccharide (LPS)-induced macrophage cells. However, whether CsV could alleviate LPS-induced liver injury in vivo and the potential mechanisms involved remain unclear. In the present study, we investigated the anti-inflammatory effects of CsV on LPS-induced acute liver injury in mice and further explored the potential mechanisms involved. Our results showed that CsV significantly attenuated elevation of alanine transaminase (ALT) and aspartate aminotransferase (AST) levels and improved liver histopathological changes in LPS-induced mice. In addition, CsV decreased serum tumor necrosis factor-α (TNF-α) and interleukin-1ß (IL-1ß) levels and inhibited mRNA expressions of inducible nitric oxide synthase (iNOS), TNF-α and IL-1ß in LPS challenged mice. Furthermore, CsV inhibited nuclear factor kappa B (NF-κB) activation by downregulating phosphorylated NF-κB, IκB-α, ERK, c-Jun N-terminal kinase (JNK) and p38 levels in the liver tissue, which ultimately decreased nucleus NF-κB protein level. In conclusion, our data suggested that CsV could be a promising drug for preventing LPS challenged liver injury since it attenuated LPS-induced inflammatory responses, partly via inhibiting NF-κB and MAPK signaling pathways.

PDGF-D promotes dermal fibroblast invasion in 3-dimensional extracellular matrix via Snail-mediated MT1-MMP upregulation.

Increasing attention has been focused on the malignant tumor microenvironment, which plays important roles in tumor occurrence, progression and metastasis. Fibroblasts are recruited by platelet-derived growth factor (PDGFs) and invade the tumor microenvironment. In the PDGF family, PDGF-B has been reported to play an important role in the recruitment and invasion programs. However, whether PDGF-D plays a role in these programs remains unclear. We generated a recombinant plasmid expressing human PDGF-D and transfected the plasmid to dermal fibroblasts to examine the effects on cell invasive activities in 3D type I collagen gels. PDGF-D plasmid transfection enhanced fibroblast invasive activities both in invasive cell numbers and invasion depth in 3D collagen gels. These effects were blocked by Snail-specific siRNA transfection. PDGF-D transfection significantly induced Snail expression at both mRNA and protein levels. PDGF-D further upregulated MT1-MMP mRNA and protein expressions and this was inhibited when Snail was knocked down by siRNA. Both Snail and MT1-MMP expressions in fibroblasts and cellular invasive activities in 3D collagen induced by PDGF-D were inhibited by LY294002, SP600125, and U1026, the inhibitors of PI3K, JNK, and ERK1/2 signaling pathways, respectively. However, no effects were observed in response to the P38MAPK signaling pathway inhibitor SB203580. These effects of PDGF-D were confirmed by using the culture supernatants of the transfectants. Taken together, these data demonstrate that PDGF-D plays important roles in the recruitment and invasion programs of fibroblasts via the activation of PI3K, JNK and ERK1/2 signaling pathways, and upregulation of Snail and downstream effecter MT1-MMP. These findings indicate that PDGF-D is an important player in the tumor microenvironment for fibroblast recruitment.

Hypoxia promotes HO-8910PM ovarian cancer cell invasion via Snail-mediated MT1-MMP upregulation.

The molecular mechanisms of ovarian cancer cell invasion under hypoxia remain unclear. Here we employed a 3D collagen model and chick chorioallantoic membrane (CAM) invasion assay to explore the influence of hypoxia on ovarian cancer cell invasion. Hypoxia (both 1% O2 and CoCl2 150 and 250 µM) induced HO-8910PM ovarian cancer cell invasion in 3D collagen and collagenolysis determined by hydroxyproline. Pretreatment with a hypoxia inducible factor-1α inhibitor, YC-1, or MMP inhibitor, GM6001, significantly inhibited 3D collagen invasion and degradation and cell proliferation. Hypoxia stimulated both mRNA and protein expressions of membrane-type 1 matrix metalloproteinase (MT1-MMP) and promoted MT1-MMP translocation to the cell surface in an YC-1 sensitive manner. MT1-siRNA transfection inhibited hypoxia-induced invasion, proliferation, and collagen degradation of cells in 3D collagen. Hypoxia stimulated Snail mRNA and protein expression as well as translocation to nucleus in an YC-1 sensitive manner. Overexpression of Snail with a recombinant plasmid in HO-8910PM cells resulted in an enhanced invasion in 3D collagen. Transfection with Snail-specific siRNA significantly decreased MT1-MMP expression and 3D collagen invasion. Hypoxia-treated cells significantly broke the upper CAM surface of 11-day-old chick embryos and infiltrated interstitial tissue, completely blocked in the presence of YC-1 or GM6001, or after MT1-MMP siRNA or Snail siRNA transfection. Together, these data suggest that hypoxia promotes HO-8910PM ovarian cancer cell traffic through 3D matrix via Snail-mediated MT1-MMP upregulation, a possible molecular mechanism of ovarian cancer cell invasion under hypoxia.

Mutations of EGFR or KRAS and expression of chemotherapy-related genes based on small biopsy samples in stage IIIB and IV inoperable non-small cell lung cancer.

PURPOSES: Epidermal growth factor receptor (EGFR) and KRAS mutations may predict the outcome of targeted drug therapy and also may be associated with the efficacy of chemotherapy in patients with non-small cell lung cancer (NSCLC). This report investigated the relation of EGFR or KRAS mutation and expression of chemotherapy-related genes, including excision repair cross-complementing 1 (ERCC1), thymidylate synthetase (TYMS), ribonucleotide reductase subunit M1 (RRM1) and class III ß-tubulin (TUBB3), as a potential explanation for these observations. METHODS: A total of 143 patients with stage IIIB and IV NSCLC from bronchoscopy or percutaneous lung biopsy obtained tumor samples were analyzed concurrently for EGFR or KRAS mutations, and mRNA expression of ERCC1, TYMS, RRM1 and TUBB3. EGFR or KRAS mutations were detected with xTAG liquidchip technology (xTAG-LCT), and mRNA expression levels of four genes were detected by branched DNA-liquidchip technology (bDNA-LCT). RESULTS: Of 143 patients, 63 tumors were positive for EGFR-activating mutations, and 16 tumors were positive for KRAS mutations. EGFR-activating mutations are more frequent in females, adenocarcinoma and non-smokers patients, and KRAS mutations are more frequent in smoking patients. ERCC1 mRNA levels were significantly associated with histological type and tumor differentiation, whereas TYMS levels were significantly associated with age. NSCLC specimens that harboring EGFR-activating mutations are more likely to express low ERCC1 and high TUBB3 mRNA levels, whereas tumors from patients with NSCLC harboring KRAS mutation are more likely to express high ERCC1 mRNA levels. CONCLUSIONS: Mutations and expression of chemotherapy-related genes may provide a basis for the selection of suitable molecular markers for individual treatment in a population with stage IIIB and IV NSCLC.

Chikusetsu saponin V attenuates MPP+-induced neurotoxicity in SH-SY5Y cells via regulation of Sirt1/Mn-SOD and GRP78/caspase-12 pathways.

Studies have shown that saponins from Panax japonicus (SPJ) possess neuroprotective effects. However, whether Chikusetsu saponin V (CsV), the most abundant member of SPJ, can exert neuroprotective effects against 1-methyl-4-phenylpyridinium ion (MPP+)-induced cytotoxicity is not known. In this study, we aimed to investigate the neuroprotective effects of CsV on MPP+-induced cytotoxicity in human neuroblastoma SH-SY5Y cells and explore its possible mechanisms. Our results show that CsV attenuates MPP+-induced cytotoxicity, inhibits ROS accumulation, and increases mitochondrial membrane potential dose-dependently. We also found that levels of Sirt1 protein and Mn-SOD mRNA significantly decreased in MPP+-treated group but were restored with CsV treatment in a dose-dependent manner. Furthermore, GRP78 protein and Caspase-12 mRNA levels were elevated by MPP+ exposure but reversed by CsV treatment. CsV inhibited the MPP+-induced downregulation of Bcl-2 and up-regulation of Bax in a dose-dependent manner and, thus, increased the ratio of Bcl-2/Bax. Overall, these results suggest that Sirt1/Mn-SOD and GRP78/Caspase-12 pathways might be involved in the CsV-mediated neuroprotective effects.

[Epithelial-mesenchymal transition induces cancer stem cell generation in human thyroid cancer cells in vitro].

OBJECTIVE: Epithelial-mesenchymal transition (EMT) has been implicated in the initiation and conversion of early stage tumors into invasive malignancies and is associated with the "stemness" of cancer cells. The present study was designed to identify whether EMT induces cancer stem cell generation and tumor progression in human thyroid cancer cells in vitro. METHODS: FTC133 cells, as EMT-negative cells, were used for EMT induction by hypoxia-inducible factor-1α (HIF-1α) transfection. And EMT features were then examined by Western blot, immunofluorescent staining, invasion and proliferation assays. Moreover, stem-like side population (SP) cells were sorted with flow cytometry from FTC133 cells before and after EMT. The proportion of SP was compared and stemness, self-renewal and tumorigenicity in vitro were identified in SP cells. RESULTS: Overexpression of HIF-1α induced FTC133 cells to undergo EMT. And it down-regulated epithelial marker E-cadherin, up-regulated mesenchymal marker vimentin and caused nucleus translocation of ß-catenin and highly invasive and metastatic properties. Most importantly, the induction of EMT promoted proportion of stem-like side population cells (0.70% vs 0.03%, P < 0.05) with higher sphere formation and clone forming capability in contrast to non-side population cells. CONCLUSIONS: EMT can induce cancer stem cell generation and tumor progression in thyroid cancers. Further understanding the role of EMT and cancer stem cells in cancer progression may reveal new preventive and therapeutic targets for thyroid cancers.

Epithelial-mesenchymal transition triggers cancer stem cell generation in human thyroid cancer cells.

Increasing evidence has shown that cancer stem cells or tumor initiating cells are the 'root cause' of malignant cancers. However, the exact origin of cancer stem cells still remains obscure in thyroid research. EMT has been implicated in the initiation and conversion of early-stage tumors into invasive malignancies and is associated with the stemness of cancer cells. Based on these facts, a new hypothesis was suggested that EMT induces cancer stem cell generation and tumor progression in human thyroid cancer cells in vitro. In the present study, FTC133 cells identified as EMT-negative cells were used for EMT induction by HIF­1α transfection. Overexpression of HIF-1α induced FTC133 cells to undergo EMT, downregulated the epithelial markers E-cadherin, upregulated the mesenchymal marker vimentin, and associated with highly invasive and metastatic properties. Most importantly, the induction of EMT promoted the stem-like side population cell proportion in the FTC133 cells. These results indicate that EMT induction promotes CSC traits and cell proportions in the thyroid cancer cells, which implies that EMT could induce cancer stem cell generation and tumor progression in thyroid cancers. Further understanding of the role of EMT and cancer stem cells in cancer progression may reveal new targets for the prevention or therapy of thyroid cancers.