Targeting cancer stemness mediated by BMI1 and MCL1 for non-small cell lung cancer treatment.

Lung cancer is the leading cause of cancer-associated death, with a global 5-year survival rate <20%. Early metastasis and recurrence remain major challenges for lung cancer treatment. The stemness property of cancer cells has been suggested to play a key role in cancer plasticity, metastasis and drug-resistance, and is a potential target for drug development. In this study, we found that in non-small cell lung cancer (NSCLC), BMI1 and MCL1 play crucial roles of cancer stemness including invasion, chemo-resistance and tumour initiation. JNK signalling serves as a link between oncogenic pathway or genotoxicity to cancer stemness. The activation of JNK, either by mutant EGFR or chemotherapy agent, stabilized BMI1 and MCL1 proteins through suppressing the expression of E3-ubiquitin ligase HUWE1. In lung cancer patient samples, high level of BMI1 is correlated with poor survival, and the expression of BMI1 is positively correlated with MCL1. A novel small-molecule, BI-44, was developed, which effectively suppressed BMI1/MCL1 expressions and inhibited tumour formation and progression in preclinical models. Targeting cancer stemness mediated by BMI1/MCL1 with BI-44 provides the basis for a new therapeutic approach in NSCLC treatment.

Impact Position Estimation for Baseball Batting with a Force-Irrelevant Vibration Feature.

In this work we propose a novel method for impact position estimation during baseball batting, which is independent of impact intensity, i.e., force-irrelevant. In our experiments, we mount a piezoelectric vibration sensor on the knob of a wooden bat to record: (1) 3600 vibration signals (waveforms) from ball-bat impacts in the static experiment-30 impacts from each of 40 positions (distributed 1-40 cm from the end of the barrel) and 3 intensities (drop heights at 75, 100, and 125 cm, resp.), and (2) 45 vibration signals from actual battings by three baseball players in the dynamic experiment. The results show that the peak amplitude of the signal in the time domain, and the peaks of the first, second, and third eigenfrequencies (EFs) of the bat all increase with the impact intensity. However, the ratios of peaks at these three EFs (1st/2nd, 2nd/3rd, and 1st/3rd) hardly change with the impact intensity, and the observation is consistent for both the static and dynamic experiments across all impact positions. In conclusion, we have observed that the ratios of peaks at the first three EFs are a force-irrelevant feature, which can be used to estimate the impact position in baseball batting.

Low-Dose Nicotine Activates EGFR Signaling via α5-nAChR and Promotes Lung Adenocarcinoma Progression.

Nicotine in tobacco smoke is considered carcinogenic in several malignancies including lung cancer. The high incidence of lung adenocarcinoma (LAC) in non-smokers, however, remains unexplained. Although LAC has long been less associated with smoking behavior based on previous epidemiological correlation studies, the effect of environmental smoke contributing to low-dose nicotine exposure in non-smoking population could be underestimated. Here we provide experimental evidence of how low-dose nicotine promotes LAC growth in vitro and in vivo. Screening of nicotinic acetylcholine receptor subunits in lung cancer cell lines demonstrated a particularly high expression level of nicotinic acetylcholine receptor subunit α5 (α 5-nAChR) in LAC cell lines. Clinical specimen analysis revealed up-regulation of α 5-nAChR in LAC tumor tissues compared to non-tumor counterparts. In LAC cell lines α 5-nAChR interacts with epidermal growth factor receptor (EGFR), positively regulates EGFR pathway, enhances the expression of epithelial-mesenchymal transition markers, and is essential for low-dose nicotine-induced EGFR phosphorylation. Functionally, low-dose nicotine requires α 5-nAChR to enhance cell migration, invasion, and proliferation. Knockdown of α 5-nAChR inhibits the xenograft tumor growth of LAC. Clinical analysis indicated that high level of tumor α 5-nAChR is correlated with poor survival rates of LAC patients, particularly in those expressing wild-type EGFR. Our data identified α 5-nAChR as an essential mediator for low-dose nicotine-dependent LAC progression possibly through signaling crosstalk with EGFR, supporting the involvement of environmental smoke in tumor progression in LAC patients.

Pigment epithelium-derived factor peptide promotes limbal stem cell proliferation through hedgehog pathway.

Expansion of limbal epithelial stem cells (LSCs) is crucial for the success of limbal transplantation. Previous studies showed that pigment epithelium-derived peptide (PEDF) short peptide 44-mer could effectively expand LSCs and maintain them in a stem-cell state, but the mechanism remained unclear. In the current study, we found that pharmacological inhibition of Sonic Hedgehog (SHh) activity reduced the LSC holoclone number and suppressed LSC proliferation in response to 44-mer. In mice subjected to focal limbal injury, 44-mer facilitated the restoration of the LSC population in damaged limbus, and such effect was impeded by the SHh or ATGL (a PEDF receptor) inhibitor. Furthermore, we showed that 44-mer increased nuclear translocation of Gli1 and Gli3 in LSCs. Knockdown of Gli1 or Gli3 suppressed the ability of 44-mer to induce cyclin D1 expression and LSC proliferation. In addition, ATGL inhibitor suppressed the 44-mer-induced phosphorylation of STAT3 at Tyr705 in LSC. Both inhibitors for ATGL and STAT3 attenuated 44-mer-induced SHh activation and LSC proliferation. In conclusion, our data demonstrate that SHh-Gli pathway driven by ATGL/STAT3 signalling accounts for the 44-mer-mediated LSC proliferation.

In silico identification of thiostrepton as an inhibitor of cancer stem cell growth and an enhancer for chemotherapy in non-small-cell lung cancer.

Cancer stem cells (CSCs) play an important role in cancer treatment resistance and disease progression. Identifying an effective anti-CSC agent may lead to improved disease control. We used CSC-associated gene signatures to identify drug candidates that may inhibit CSC growth by reversing the CSC gene signature. Thiostrepton, a natural cyclic oligopeptide antibiotic, was the top-ranked candidate. In non-small-cell lung cancer (NSCLC) cells, thiostrepton inhibited CSC growth in vitro and reduced protein expression of cancer stemness markers, including CD133, Nanog and Oct4A. In addition, metastasis-associated Src tyrosine kinase signalling, cell migration and epithelial-to-mesenchymal transition (EMT) were all inhibited by thiostrepton. Mechanistically, thiostrepton treatment led to elevated levels of tumour suppressor miR-98. Thiostrepton combined with gemcitabine synergistically suppressed NSCLC cell growth and induced apoptosis. The inhibition of NSCLC tumours and CSC growth by thiostrepton was also demonstrated in vivo. Our findings indicate that thiostrepton, an established drug identified in silico, is an inhibitor of CSC growth and a potential enhancer of chemotherapy in NSCLC.

Pigment epithelium-derived factor peptide reverses mouse age-related meibomian gland atrophy.

Age-related meibomian gland (MG) atrophy, characterized by decreased meibocyte proliferation, is one of the causes of meibomian gland dysfunction (MGD), which leads to dry eye disease. Currently, there is no available treatment effectively preventing or reversing the decreased cell proliferation and acinar tissue atrophy. In this study, we investigated the therapeutic effects of a pigment epithelium-derived factor (PEDF) peptide in treating this condition. We found abundant expression of PEDF in the nucleus of acinar basal cells, but not in mature meibocytes, and that the expression levels were significantly decreased in the aged mice. We next treated the aged mice (15-month old) with atrophic MGs using a synthetic PEDF-derived peptide 29-mer (residues 93-121). We found that 29-mer effectively stimulated acinar basal cell proliferation and the following mature meibocyte proliferation in the atrophied MGs. In addition, the treatment increased ΔNp63 and Lrig1 expressions in acinar basal cells. Finally, the aged mice receiving the treatment showed MG growth and improved tear film break-up time. In conclusion, the 29-mer treatment is effective in promoting MG acinar basal cell proliferation and enlarging the acinar size of MG, as well as improving MG function in aged mice, suggesting a therapeutic potential of the PEDF-derived short peptide in ameliorating age-related MGD.

The role of EpCAM in tumor progression and the clinical prognosis of endometrial carcinoma.

OBJECTIVE: EpCAM is a transmembrane glycoprotein that functions as an epithelial marker in endometrial tissues. However, the correlation between EpCAM and endometrial carcinoma (EC) is not clear. METHODS: This study investigated the association between EpCAM and EC. Immunohistochemistry staining and bioinformatics analysis disclosed the clinical importance of low EpCAM expression. The migratory ability of cells expressing low EpCAM levels was studied in transwell invasion assays in vitro and an orthotopic intra-uterine tumor injection model in vivo. The Connectivity MAP was used to identify drugs that effectively inhibit cells with low EpCAM expression. RESULTS: According to immunohistochemistry analysis results, low EpCAM expression was associated with an advanced stage and lymph node metastasis in patients with endometrioid EC, and high EpCAM expression favored survival. EpCAM silencing promoted cell invasion, and EpCAM re-expression in EpCAM-silenced EC cells attenuated their invasiveness. EpCAM suppression in an orthotopic uterine implantation model promoted the lymph node metastasis of EC cells. According to quantitative PCR and promoter reporter analyses, estrogen receptor alpha signaling regulated EpCAM expression by enhancing its promoter activity. As shown in the Connectivity MAP analysis, transamin inhibited the invasiveness of EpCAM-silenced EC cells. CONCLUSIONS: The loss of EpCAM may increase the malignancy of EC, and these findings provide new insights into the prognostic role of EpCAM in patients with EC.

MicroRNA-7 Compromises p53 Protein-dependent Apoptosis by Controlling the Expression of the Chromatin Remodeling Factor SMARCD1.

We previously demonstrated that the epidermal growth factor receptor (EGFR) up-regulated miR-7 to promote tumor growth during lung cancer oncogenesis. Several lines of evidence have suggested that alterations in chromatin remodeling components contribute to cancer initiation and progression. In this study, we identified SMARCD1 (SWI/SNF-related, matrix-associated, actin-dependent regulator of chromatin, subfamily d, member 1) as a novel target gene of miR-7. miR-7 expression reduced SMARCD1 protein expression in lung cancer cell lines. We used luciferase reporters carrying wild type or mutated 3'UTR of SMARCD1 and found that miR-7 blocked SMARCD1 expression by binding to two seed regions in the 3'UTR of SMARCD1 and down-regulated SMARCD1 mRNA expression. Additionally, upon chemotherapy drug treatment, miR-7 down-regulated p53-dependent apoptosis-related gene BAX (BCL2-associated X protein) and p21 expression by interfering with the interaction between SMARCD1 and p53, thereby reducing caspase3 cleavage and the downstream apoptosis cascades. We found that although SMARCD1 sensitized lung cancer cells to chemotherapy drug-induced apoptosis, miR-7 enhanced the drug resistance potential of lung cancer cells against chemotherapy drugs. SMARCD1 was down-regulated in patients with non-small cell lung cancer and lung adenocarcinoma cell lines, and SMARCD1 and miR-7 expression levels were negatively correlated in clinical samples. Our investigation into the involvement of the EGFR-regulated microRNA pathway in the SWI/SNF chromatin remodeling complex suggests that EGFR-mediated miR-7 suppresses the coupling of the chromatin remodeling factor SMARCD1 with p53, resulting in increased chemo-resistance of lung cancer cells.

YM500v2: a small RNA sequencing (smRNA-seq) database for human cancer miRNome research.

We previously presented YM500, which is an integrated database for miRNA quantification, isomiR identification, arm switching discovery and novel miRNA prediction from 468 human smRNA-seq datasets. Here in this updated YM500v2 database (http://ngs.ym.edu.tw/ym500/), we focus on the cancer miRNome to make the database more disease-orientated. New miRNA-related algorithms developed after YM500 were included in YM500v2, and, more significantly, more than 8000 cancer-related smRNA-seq datasets (including those of primary tumors, paired normal tissues, PBMC, recurrent tumors, and metastatic tumors) were incorporated into YM500v2. Novel miRNAs (miRNAs not included in the miRBase R21) were not only predicted by three independent algorithms but also cleaned by a new in silico filtration strategy and validated by wetlab data such as Cross-Linked ImmunoPrecipitation sequencing (CLIP-seq) to reduce the false-positive rate. A new function 'Meta-analysis' is additionally provided for allowing users to identify real-time differentially expressed miRNAs and arm-switching events according to customer-defined sample groups and dozens of clinical criteria tidying up by proficient clinicians. Cancer miRNAs identified hold the potential for both basic research and biotech applications.

Galectin-3 modulates the EGFR signalling-mediated regulation of Sox2 expression via c-Myc in lung cancer.

Galectin-3 is a ubiquitous lectin exerting multiple cellular functions such as RNA splicing, protein trafficking and apoptosis. Its expression is positively correlated with the poor prognosis in lung cancer patients. Galectin-3 can promote cancer progression through its effects on cell proliferation, cell survival or cancer metastasis. However, the role of galectin-3 in the regulation of cancer stem-like cells (CSCs) is still unclear. Here, we investigated the hypothesis that galectin-3 might regulate lung CSCs via the EGF receptor (EGFR) signaling pathway. In our study, galectin-3 facilitated EGFR activation and enhanced the sphere formation activity of lung cancer cells. Furthermore, galectin-3 promoted Sox2 expression in an EGFR activation-dependent manner; importantly, forced expression of Sox2 blunted the effect of galectin-3 knockdown on lung cancer sphere formation ability. These results suggest that galectin-3 promotes EGFR activation leading to the upregulation of Sox2 expression and lung CSCs properties. Moreover, we showed that the carbohydrate-binding activity of galectin-3 was important for the regulation of EGFR activation, Sox2 expression and sphere formation. We have recently reported that c-Myc is a transcriptional activator of Sox2. We further found that galectin-3 enhanced c-Myc protein stability leading to increased c-Myc binding to the Sox2 gene promoter. We also examined the effect of the stemness factors, Oct4, Nanog and Sox2 on the expression of galectin-3. We found that Oct4 enhanced galectin-3 expression. Our results together suggest that galectin-3 enhances lung cancer stemness through the EGFR/c-Myc/Sox2 axis; Oct4, in turn, promotes galectin-3 expression, forming a positive regulatory loop in lung CSCs.

The emerging role of SOX2 in cell proliferation and survival and its crosstalk with oncogenic signaling in lung cancer.

Tumor cells have long been observed to share several biological characteristics with normal stem/progenitor cells; however, the oncogenic mechanisms underlying the lung stem/progenitor cell signaling remain elusive. Here, we report that SOX2, a self-renewal factor in lung stem/progenitor cells, is highly expressed in a subclass of lung cancer cells, the proliferation, survival, and chemoresistance of which are dependent on SOX2 signaling. Overexpression of SOX2 promotes oncogenic phenotypes in lung cancer cells; knockdown of SOX2 attenuated cell proliferation. We observed that SOX2 increased the expression of epidermal growth factor receptor (EGFR), and EGFR activation further upregulated SOX2 levels, forming a positive feedback loop. SOX2 expression promoted chemoresistance, and silencing of SOX2 perturbed mitochondrial function, causing marked apoptosis and autophagy. SOX2 induced BCL2L1, the ectopic expression of which rescued the effects of SOX2 silencing on apoptosis, autophagy, and mitochondrial function. SOX2 promoted tumor formation, along with increased cell proliferation in a xenograft mouse model. SOX2 expression is associated with poor prognosis in lung cancer patients; moreover, SOX2, EGFR, and BCL2L1 expression levels were significantly correlated in lung tumors. Our findings support the emerging role of SOX2 in cell proliferation and survival by eliciting oncogenic EGFR and BCL2L1 signaling with potential applications as a prognosis marker and a therapeutic target in lung cancer.

The PML isoform IV is a negative regulator of nuclear EGFR's transcriptional activity in lung cancer.

Epidermal growth factor receptor (EGFR) is a membrane-bound receptor tyrosine kinase, which can transduce intracellular signals responsible for cell proliferation. It is frequently overexpressed and/or constitutively activated in non-small cell lung cancer and thus is considered as a major cause of this disease. Recently, EGFR has been found in the nucleus where the nuclear EGFR (nEGFR) can function as a transcription factor activating the transcription of genes such as cyclin D1 gene (CCND1), which is essential for cell proliferation. Nevertheless, how nEGFR's transcriptional activity is regulated remains unclear. Promyelocytic leukemia protein (PML) is a tumor suppressor, which is lost in various cancers including lung cancer. However, the role of PML in the suppression of lung cancer growth is still unclear. When we investigated the role of PML in the regulation of lung cancer cell growth, we found that PML isoform IV (PMLIV) preferentially represses the growth of lung cancer cells bearing constitutively active EGFR. Besides, when growing in the EGFR activating conditions, the growth of EGFR wild-type bearing A549 cells has been repressed by PMLIV overexpression. We also found that PMLIV can interact physically with nEGFR and represses the transcription of nEGFR target genes. We showed that PMLIV is recruited by nEGFR to the target promoters and reduces the promoter histone acetylation level via HDAC1. Together, our results suggest that PMLIV interacts with nEGFR upon EGFR activation and represses the transcription of nEGFR target genes such as CCND1 and thus leading to inhibition of the lung cancer cell growth.

Polyethyleneimine and DNA nanoparticles-based gene therapy for acute lung injury.

Acute lung injury (ALI) is a devastating clinical syndrome causing a substantial mortality, but to date without any effective pharmacological management in clinic. Here, we tested whether nanoparticles based on polyethylenimine (PEI) and DNA could be a potential treatment. In mouse model of ALI induced by lipopolysaccharide (LPS) (10mg/kg), intravenous injection of PEI/DNA mediated a rapid (in 6h) and short-lived transgene expression in lung, with alveolar epithelial cells as major targets. When ß2-Adrenergic Receptor (ß2AR) was applied as therapeutic gene, PEI/ß2AR treatment significantly attenuated the severity of ALI, including alveolar fluid clearance, lung water content, histopathology, bronchioalveolar lavage cellularity, protein concentration, and inflammatory cytokines in mice with pre-existing ALI. In high-dose LPS (40 mg/kg)-induced ALI, post-injury treatment of PEI/ß2AR significantly improved the 5-day survival of mice from 28% to 64%. These data suggest that PEI/DNA nanoparticles could be an effective agent in future clinical application for ALI treatment. FROM THE CLINICAL EDITOR: In this novel study, PEI/DNA nanoparticles are presented as an effective agent for the treatment of the devastating and currently untreatable syndrome of acute lung injury, using a rodent model system.

Stabilization of AURKA by the E3 ubiquitin ligase CBLC in lung adenocarcinoma.

CBL family proteins (CBL, CBLB and CBLC in mammals) are E3 ubiquitin ligases of protein tyrosine kinases. CBL mediates the lysosomal degradation of activated EGFR through K63-linked ubiquitination, while CBLC has an oncogenic function by positively regulating EGFR activation through K6 and K11-linked ubiquitination in EGFR mutant lung adenocarcinoma (LAD). Here, we used immunoprecipitation and mass spectrometry to study the CBLC interactome, and found that CBLC is also involved in cell cycle regulation by stabilizing Aurora kinase A (AURKA). CBLC interacted with the kinase domain of AURKA and positively regulated the stability of AURKA by conjugating monoubiquitination and K11/K63-linked polyubiquitination, which are protective from degrading K11/K48 polyubiquitination. CBLC depletion markedly decreased the half-life of AURKA in cycloheximide-treated LAD cells. When LAD cells were synchronized with double thymidine block at the G1/S boundary and then released into mitotic arrest, CBLC depletion delayed the accumulation and activation of AURKA and prevented cancer cells from entering mitosis. CBLC deficiency significantly delayed cell cycle progression, reduced the mitotic population, and increased apoptosis of LAD cells. Targeting CBLC inhibited tumor growth of LAD cells and enhanced their sensitivity to paclitaxel in xenograft models. Immunohistochemical staining of the tissue microarray also revealed a positive correlation between the expression of CBLC and AURKA in normal and LAD tissues, further supporting the positive regulation of AURKA expression by CBLC. In summary, these findings indicate that the oncogenic E3 ligase CBLC plays a role in mitotic entry by stabilizing AURKA via ubiquitination in LAD. This work demonstrates that targeting CBLC combined with paclitaxel might be a potential option for the treatment of LAD patients who have no available targeted therapies.

Epigenetic activation of human kallikrein 13 enhances malignancy of lung adenocarcinoma by promoting N-cadherin expression and laminin degradation.

The tissue kallikrein (KLK) family contains 15 genes (KLK1-KLK15) tandemly arranged on chromosome 19q13.4 that forms the largest cluster of contiguous protease genes in the human genome. Here, we provide mechanistic evidence showing that the expression of KLK13, one of the most recently identified family members, is significantly up-regulated in metastatic lung adenocarcinoma. Whilst overexpression of KLK13 resulted in an increase in malignant cell behavior, knockdown of its endogenous gene expression caused a significant decrease in cell migratory and invasive properties. Functional studies further demonstrated that KLK13 is activated via demethylation of its upstream region. The elevated KLK13 protein then enhances the ability of tumor cells to degrade extracellular laminin that, subsequently, facilitates cell metastatic potential in the in vivo SCID mouse xenograft model. KLK13 was also found to induce the expression of N-cadherin to help promote tumor cell motility. Together, these results reveal the enhancing effects of KLK13 on tumor cell invasion and migration, and that it may serve as a diagnostic/prognostic marker and a potential therapeutic target for lung cancer.

Alisertib inhibits migration and invasion of EGFR-TKI resistant cells by partially reversing the epithelial-mesenchymal transition.

Epithelial growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) have been widely used in the clinical treatment of non-small cell lung cancer (NSCLC) patients with EGFR mutations. Previous studies have shown that Aurora kinase A (AURKA) is overexpressed in a broad spectrum of cancer cells, which can induce epithelial-mesenchymal transition (EMT) and contribute to the occurrence of acquired EGFR-TKI resistance. However, whether the inhibition of AURKA could overcome EGFR-TKI resistance or reverse the EMT in TKI-resistant NSCLC cells remains unclear. In the current study, we established three EGFR-TKI-resistant cell lines and analyzed their expression profiles by RNA sequencing. The results revealed that the EMT pathway is significantly upregulated in the three cell lines with EGFR-TKI resistance. The phosphorylation of AURKA at Thr 288 was also upregulated, suggesting that the activation of AURKA plays an important role in the occurrence of EGFR-TKI resistance. Interestingly, the AURKA inhibitor, alisertib treatment restored the susceptibility of resistant cells to EGFR-TKIs and partially reversed the EMT process, thereby reducing migration and invasion in EGFR-TKI-resistant cells. This study provides evidence that targeting AURKA signaling pathway by alisertib may be a novel approach for overcoming EGFR-TKI resistance and for the treatment of metastatic EGFR-TKIs in NSCLC patients.

TAZ negatively regulates the novel tumor suppressor ANKRD52 and promotes PAK1 dephosphorylation in lung adenocarcinomas.

Lung cancer is the leading cause of cancer death, and therefore the discovery of novel therapeutic targets is crucial. P21-activated kinase (PAK1) is an important oncogene involved in the signaling of actin cytoskeleton organization. Although PAK1 inhibition has been shown to suppress cancer progression, specific PAK1 inhibitors are not available due to the complex structure and insufficient understanding of this kinase. The Hippo signaling effector TAZ is known to be elevated in multiple human cancers and to promote cancer metastasis. This study aimed to explore the role of TAZ in regulating the tumor suppressor ankyrin repeat domain 52 (ANKRD52) and PAK1 activity. A negative correlation between TAZ and ANKRD52 was observed, with knockdown of TAZ leading to enhanced ANKRD52 promoter activity and increased mRNA levels. Moreover, reduced ANKRD52 levels were associated with late-stage lung cancer. Knockdowns of ANKRD52 resulted in elevated cell mobility, while forced ANKRD52 expression attenuated cell mobility. ANKRD52 is a subunit of the protein phosphatase 6 (PP6) holoenzyme. Mass spectrometry analysis revealed the interaction between PAK1 and the ANKRD52-PP6 complex. Knockdown of ANKRD52 or PP6c resulted in upregulated PAK1 phosphorylation. Our study demonstrates that the novel tumor suppressor protein ANKRD52 is transcriptionally inhibited by TAZ, regulating cell mobility through interactions with PP6c and dephosphorylation of PAK1.

AGEs-Induced Calcification and Apoptosis in Human Vascular Smooth Muscle Cells Is Reversed by Inhibition of Autophagy.

Vascular calcification (VC) in macrovascular and peripheral blood vessels is one of the main factors leading to diabetes mellitus (DM) and death. Apart from the induction of vascular calcification, advanced glycation end products (AGEs) have also been reported to modulate autophagy and apoptosis in DM. Autophagy plays a role in maintaining the stabilization of the external and internal microenvironment. This process is vital for regulating arteriosclerosis. However, the internal mechanisms of this pathogenic process are still unclear. Besides, the relationship among autophagy, apoptosis, and calcification in HASMCs upon AGEs exposure has not been reported in detail. In this study, we established a calcification model of SMC through the intervention of AGEs. It was found that the calcification was upregulated in AGEs treated HASMCs when autophagy and apoptosis were activated. In the country, AGEs-activated calcification and apoptosis were suppressed in Atg7 knockout cells or pretreated with wortmannin (WM), an autophagy inhibitor. These results provide new insights to conduct further investigations on the potential clinical applications for autophagy inhibitors in the treatment of diabetes-related vascular calcification.

The investigation of mitogen-activated protein kinase phosphatase-1 as a potential pharmacological target in non-small cell lung carcinomas, assisted by non-invasive molecular imaging.

BACKGROUND: Invasiveness and metastasis are the most common characteristics of non small cell lung cancer (NSCLC) and causes of tumour-related morbidity and mortality. Mitogen-activated protein kinases (MAPKs) signalling pathways have been shown to play critical roles in tumorigenesis. However, the precise pathological role(s) of mitogen-activated protein kinase phosphatase-1 (MKP-1) in different cancers has been controversial such that the up-regulation of MKP-1 in different cancers does not always correlate to a better prognosis. In this study, we showed that the induction of MKP-1 lead to a significant retardation of proliferation and metastasis in NSCLC cells. We also established that rosiglitazone (a PPARgamma agonist) elevated MKP-1 expression level in NSCLC cells and inhibited tumour metastasis. METHODS: Both wildtype and dominant negative forms of MKP-1 were constitutively expressed in NSCLC cell line H441GL. The migration and invasion abilities of these cells were examined in vitro. MKP-1 modulating agents such as rosiglitazone and triptolide were used to demonstrate MKP-1's role in tumorigenesis. Bioluminescent imaging was utilized to study tumorigenesis of MKP-1 over-expressing H441GL cells and anti-metastatic effect of rosiglitazone. RESULTS: Over-expression of MKP-1 reduced NSCLC cell proliferation rate as well as cell invasive and migratory abilities, evident by the reduced expression levels of MMP-2 and CXCR4. Mice inoculated with MKP-1 over-expressing H441 cells did not develop NSCLC while their control wildtype H441 inoculated littermates developed NSCLC and bone metastasis. Pharmacologically, rosiglitazone, a peroxisome proliferator activated receptor-gamma (PPARgamma) agonist appeared to induce MKP-1 expression while reduce MMP-2 and CXCR4 expression. H441GL-inoculated mice receiving daily oral rosiglitazone treatment demonstrated a significant inhibition of bone metastasis when compared to mice receiving sham treatment. We found that rosiglitazone treatment impeded the ability of cell migration and invasion in vitro. Cells pre-treated with triptolide (a MKP-1 inhibitor), reversed rosiglitazone-mediated cell invasion and migration. CONCLUSION: The induction of MKP-1 could significantly suppress the proliferative and metastatic abilities of NSCLC both in vitro and in vivo. Therefore, MKP-1 could be considered as a potential therapeutic target in NSCLC therapy and PPARgamma agonists could be explored for combined chemotherapy.