The response of microbial community structure and sediment properties to anthropogenic activities in Caohai wetland sediments.

This study aimed to investigate the response of sediment microbial communities (including bacteria and archaeal groups) in Caohai Lake to anthropogenic activities. The sediment samples were collected from the regions with high anthropogenic interference and low anthropogenic interference. Their physicochemical properties and enzyme activities were analyzed, and the bacterial and archaeal communities were investigated using high-throughput sequencing technology. The results showed that the physicochemical characters changed by anthropogenic activities were the important factors that influenced enzyme activities, alpha diversity, key functional taxa, and community structure. And the impact of anthropogenic activities on microbial communities might follow a non-linear pattern. Furthermore, few significant differences of alpha indices between the high and low disturbed areas, but clear differences of microbial community composition analysis and beta-diversity analysis were observed. The hypothesis was proved that the intensity of anthropogenic impacts in Caohai had not reached the potential thresholds. The best distinguish biomarkers between the two areas and the most related key nodes among the network did not always have a high microbial abundance. The anthropogenic activities might influence the microbial community by affecting a small number of the key taxon in the ecological network. These findings provided a valuable understanding of how sediment microorganisms respond to anthropogenic activities in Caohai Lake.

Knockdown of G-protein-signaling modulator 2 promotes metastasis of non-small-cell lung cancer by inducing the expression of Snail.

Non-small-cell lung cancer (NSCLC) is the leading global cause of cancer-related death. Due to the lack of reliable diagnostic or prognostic biomarkers, the prognosis of NSCLC remains poor. Consequently, there is an urgent need to explore the mechanisms underlying this condition in order to identify effective biomarkers. G-protein-signaling modulator 2 (GPSM2) is widely recognized as a determinant of mitotic spindle orientation. However, its role in cancer, especially NSCLC, remains uncertain. In this study, we found that GPSM2 was downregulated in NSCLC tissues and was correlated with a poor prognosis. Furthermore, the knockdown of GPSM2 promoted NSCLC cell metastasis in vitro and in vivo and accelerated the process of epithelial-mesenchymal transition (EMT). Mechanistically, we showed that silencing GPSM2 induced cell metastasis and EMT through the ERK/glycogen synthase kinase-3ß/Snail pathway. These results confirm that GPSM2 plays an important role in NSCLC. Moreover, GPSM2, as an independent prognostic factor, could be a potential prognostic biomarker and drug target for NSCLC.

Lymecycline reverses acquired EGFR-TKI resistance in non-small-cell lung cancer by targeting GRB2.

Epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) were first-line treatments for NSCLC patients with EGFR-mutations. However, about 30 % of responders relapsed within six months because of acquired resistance. In this study, we used Connectivity Map (CMap) to discover a drug capable of reversing acquired EGFR-TKIs resistance. To investigate Lymecycline's ability to reverse acquired EGFR-TKIs resistance, two Icotinib resistant cell lines were constructed. Lymecycline's ability to suppress the proliferation of Icotinib resistant cells in vitro and in vivo was then evaluated. Molecular targets were predicted using network pharmacology and used to identify the molecular mechanism. Growth factor receptor-bound protein 2 (GRB2) is an EGFR-binding adaptor protein essential for EGFR phosphorylation and regulation of AKT/ERK/STAT3 signaling pathways. Lymecycline targeted GRB2 and inhibited the resistance of the cell cycle to EGFR-TKI, arresting disease progression and inducing apoptosis in cancer cells. Combined Lymecycline and Icotinib treatment produced a synergistic effect and induced apoptosis in HCC827R5 and PC9R10 cells. Cell proliferation in resistant cancer cells was significantly inhibited by the combined Lymecycline and Icotinib treatment in mouse models. Lymecycline inhibited the resistance of the cell cycle to EGFR-TKI and induced apoptosis in NSCLC by inhibiting EGFR phosphorylation and GRB2-mediated AKT/ERK/STAT3 signaling pathways. This provided strong support that Lymecycline when combined with EGFR targeting drugs, enhanced the efficacy of treatments for drug-resistant NSCLC.

Suppressed expression of Cbl-b by NF-κB mediates icotinib resistance in EGFR-mutant non-small-cell lung cancer.

Although epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) could greatly improve the prognosis of NSCLC patients harboring activating EGFR mutations, drug resistance still remains a major obstacle to successful treatment. Our previous study found that the EGFR-TKI icotinib could upregulate the expression of Casitas-B-lineage lymphoma protein-B (Cbl-b), an E3 ubiquitin ligase. In the present study, we aimed to clarify the potential role of Cbl-b in the resistance to icotinib, and the underlying mechanisms using EGFR-mutant cell lines. We found that icotinib inhibited the proliferation of mutant-EGFR NSCLC cells (PC9 and HCC827), and upregulated the expression of Cbl-b at both the protein and mRNA levels. Cbl-b knockdown decreased the sensitivity of PC9 and HCC827 cells to icotinib, and partially restored icotinib-inhibited AKT activation in PC9 cells. On the contrary, Cbl-b overexpression could partly reverse the drug resistance in PC9 icotinib-resistant cells (PC9/IcoR). Moreover, overexpressing p65, the main member of transcription factor NF-κB family, reversed the icotinib-mediated upregulation of Cbl-b. Collectively, these data suggest that icotinib could upregulate Cbl-b mediated by NF-κB inhibition, and Cbl-b contribute to the icotinib sensitivity in EGFR-mutant NSCLC cells. This study highlights that low expression of Cbl-b might be the key obstacles in the efficacy of icotinib therapy.

Extracellular production of recombinant N-glycosylated anti-VEGFR2 monobody in leaky Escherichia coli strain.

OBJECTIVE: To improve the production yield of N-glycosylated anti-VEGFR2 (vascular endothelial growth factor receptor 2) monobody (FN3VEGFR2-Gly) in lpp knockout Escherichia coli cells harboring Campylobacter jejuni N-glycosylation pathway. RESULTS: The leaky CLM37-Δlpp strain efficiently secreted FN3VEGFR2-Gly into culture medium. The extracellular levels of glycosylated FN3VEGFR2-Gly in CLM37-Δlpp culture medium were approximately 11 and 15 times higher compared to those in CLM37 cells via IPTG and auto-induction, respectively. In addition, the highest level of total glycosylated FN3VEGFR2-Gly (70 ± 3.4 mg/L) was found in culture medium via auto-induction. Furthermore, glycosylated FN3VEGFR2-Gly was more stable than unglycosylated FN3VEGFR2-Gly in this expression system, but their bioactivities were relatively similar. CONCLUSIONS: Lpp knockout leaky E. coli strain combined with auto-induction method can enhance the extracellular production of homogenous N-glycosylated FN3VEGFR2-Gly, and facilitate the downstream protein purification. The findings of this study may provide practical implications for the large-scale production and cost-effective harvesting of N-glycosylation proteins.

ß-Elemene inhibits peritoneal metastasis of gastric cancer cells by modulating FAK/Claudin-1 signaling.

Peritoneal metastasis is common in advanced gastric cancer patients and is typically associated with a worse prognosis. ß-Elemene is a natural compound that can be isolated from the Curcuma wenyujin plant and has been widely used in China to treat a variety of cancers. However, the anti-metastatic impacts of ß-elemene on gastric cancer remain unknown. In our study, we found that ß-elemene significantly inhibited the migration and invasive capacity of gastric cells in vitro and inhibited the capacity of gastric cancer cells to peritoneally diffuse and metastasize in vivo. Mechanistically, we demonstrated that the anti-metastatic effects of ß-elemene were exerted by downregulating the expression of Claudin-1. Furthermore, ß-elemene was found to inhibit the metastatic capacity of cells by downregulating FAK phosphorylation, which regulated Claudin-1. Overall, our result revealed that ß-elemene inhibited peritoneal metastases from gastric cancer by modulating the FAK/Claudin-1 pathway.

Actinobacterial community in Shuanghe Cave using culture-dependent and -independent approaches.

Karst caves, considering to be the "arks" of biodiversity, often contain high levels of endemism. In the present study, the actinobacterial community in Shuanghe Cave, the longest cave in Asia, was analyzed for the first-time using culture-dependent and -independent (16S rRNA amplicon sequencing) approaches. The amplicon sequencing analysis revealed a broad taxonomic diversity in Shuanghe Cave, including 19 phyla (predominantly Actinobacteria) and 264 different genera. While the culture-dependent method got the unrepresentative but supplemental result, a total of 239 actinomycetes were isolated and were identified to seven genera based on culture features and 16S rRNA tests. Among the three habitats (soil, rock soil, and bat guano), the dominant phyla did not differ significantly, while the dominant genus community varied among different habitats, and the richness in soil and rock soil samples was higher than that in bat guano. Furthermore, 16 isolate strains showed antimicrobial activity, especially, the strain S142 (Streptomyces badius) and S761 (Actinoplanes friuliensis) exhibited the most promising activity against various pathogens. Overall, this work showed the abundant bacterial diversity and the antimicrobial potential of the isolates from the Shuanghe Cave.

AZ304, a novel dual BRAF inhibitor, exerts anti-tumour effects in colorectal cancer independently of BRAF genetic status.

BACKGROUND: BRAF mutation is associated with poor clinical outcome of patients with malignant tumours, and mediates resistance to chemotherapy and targeted therapy. This study aimed to determine whether V600E mutant and wild type BRAF colorectal cancers exhibit distinct sensitivities to the dual BRAF inhibitor AZ304. METHODS: Kinase activity was assessed by the AlphaScreen assay. Then, MTT assay, EdU assay, colony-formation assay and Western blot were performed to evaluate the anti-tumour effects of AZ304 in vitro. In vivo efficacy was investigated by xenograft analysis and immunohistochemistry. RESULTS: AZ304 exerted potent inhibitory effects on both wild type and V600E mutant forms of the serine/threonine-protein kinase BRAF, with IC50 values of 79 nM and 38 nM, respectively. By suppressing ERK phosphorylation, AZ304 effectively inhibited a panel of human cancer cell lines with different BRAF and RAS genetic statuses. In selected colorectal cancer cell lines, AZ304 significantly inhibited cell growth in vitro and in vivo, regardless of BRAF genetic status. In addition, the EGFR inhibitor Cetuximab enhanced the potency of AZ304 independently of BRAF mutational status. CONCLUSIONS: The BRAF inhibitor AZ304 has broad spectrum antitumour activity, which is significantly enhanced by combination with Cetuximab in colorectal cancers in vitro and in vivo.

Limb-Bud and Heart Attenuates Growth and Invasion of Human Lung Adenocarcinoma Cells and Predicts Survival Outcome.

BACKGROUND/AIMS: The transcription cofactor limb-bud and heart (LBH) is involved in embryonic development. However, its role in human lung cancer, especially lung adenocarcinoma (LUAD), remains unclear. METHODS: A public database and tissue microarray (TMA) were used to compare differences in LBH expression and its relationship with clinical characteristics. Tissue from an additional 70 LUAD patients with follow-up records was used to explore the correlation of LBH expression with prognosis. Cellular and molecular studies validated the role of LBH in LUAD growth and invasion. RESULTS: LBH was significantly down-regulated in lung cancer tissue samples and was correlated with the prognosis and clinical characteristics of lung cancer patients based on a public database and TMA. Survival analysis revealed that LBH-negative expression was associated with poor overall survival of LUAD patients (P = 0.021). Cox regression analysis showed that LBH expression status was a favorable independent prognostic factor (hazard ratio = 0.120, 95% confidence interval = 0.016-0.894, P = 0.039). LBH knockdown accelerated LUAD cell proliferation, migration, and invasion. Furthermore, bioinformatics analysis indicated that LBH was significantly related to the cell adhesion pathway. Western blot analysis confirmed that LBH could regulate the expression of integrin family members (integrin-α1, integrin-α2, integrin-α4, integrin-αv, and integrin-ß4). CONCLUSION: Our data suggest that LBH plays an important role in lung cancer. Importantly, LBH is an independent prognostic factor in LUAD and can attenuate cell growth and invasion. LBH may be a potential prognostic biomarker in LUAD patients.

Tyrosine kinase inhibitor-induced IL-6/STAT3 activation decreases sensitivity of EGFR-mutant non-small cell lung cancer to icotinib.

Tyrosine kinase Inhibitors (TKIs) of epidermal growth factor receptor (EGFR) has considerably benefited for non-small cell lung carcinomas (NSCLC) harbor mutations in EGFR. However, the factors attenuating EGFR-TKI efficiency are obstacles to inhibit the proliferation of EGFR-mutant NSCLC cells successfully. Clarifying the insensitivity mechanisms of EGFR-TKI would help to develop new treatment strategy. In this study, the sensitivity of EGFR-mutant NSCLC cell lines, PC9 and HCC827, to icotinib was detected. Similar with other EGFR-TKIs such as gefitinib and erlortinib in previous research, the proliferation of two cell lines was apparently inhibited. However, we surprisingly found that contrast with the suppression of EGFR-AKT/ERK pathway, STAT3 was significantly activated in PC9 cells with the treatment of icotinib, but not in HCC827 cells. Further study confirmed that icotinib concomitantly induced IL-6 secretion and src activation in PC9 cells. Moreover, with the treatment of IL-6 neutralizing antibody or src inhibitor, dasatinib, icotinib-induced phosphorylation of STAT3 was reduced, as well as the sensitivity of PC9 to icotinib was also partially increased. Our results suggest that Src/IL-6/STAT3 bypass pathway is activated to maintain cell survival when the EGFR pathway was inhibited by TKIs, even in some EGFR-mutant NSCLC cells sensitive to TKIs. This finding provides a groundwork for potential combinatorial treatment with TKIs and Src or STAT3 inhibitor to improve icotinib sensitivity.

miR-200a enhances TRAIL-induced apoptosis in gastric cancer cells by targeting A20.

Tumor necrosis factor-alpha-related apoptosis-inducing ligand (TRAIL) triggers apoptosis by inducing the death-inducing signaling complex (DISC) formation. Recently, TNFα-induced protein 3 (TNFAIP3, A20) was reported to prevent TRAIL-induced caspase 8 cleavage in the DISC by mediating ubiquitination of RIP1 in glioblastoma. However, whether A20 regulates caspase 8 cleavage in the DISC when TRAIL induces apoptosis in gastric cancer cells is unknown. In the present study, A20 interacted with RIP1 and DR4 in MGC803 and SGC7901 gastric cancer cells. Treatment with TRAIL promoted the A20-mediated polyubiquitination of RIP1, caspase 8 translocation into the DISC, and the interaction between caspase 8 and ubiquitinated RIP1. Inhibition of A20 expression prevented the polyubiquitination of RIP1 and promoted caspase 8 cleavage. Moreover, our data clarified that A20 is a target of miR-200a. Overexpression of miR-200a inhibited A20 expression and polyubiquitination of RIP1 and then promoted cleavage of caspase 8 and TRAIL-triggered apoptosis. Taken together, our results indicate that miR-200a enhanced TRAIL-triggered apoptosis in gastric cancer cells by targeting A20.

ß-elemene increases the sensitivity of gastric cancer cells to TRAIL by promoting the formation of DISC in lipid rafts.

ß-Elemene, an anti-cancer drug extracted from traditional Chinese medicinal herb, showed anti-tumor effects on gastric cancer cells. Our previous studies reported gastric cancer cells are insensitive to TRAIL. However, whether ß-elemene could enhance anti-cancer effects of TRAIL on gastric cancer cells is unknown. In our present study, ß-elemene prevented gastric cancer cell viability in dose-dependent manner, and when combined with TRAIL, obviously inhibited proliferation and promoted apoptosis in gastric cancer cells. Compared to ß-elemene or TRAIL alone, treatment with ß-elemene and TRAIL obviously promoted DR5 clustering as well as translocation of Caspase-8, DR5 and FADD into lipid rafts. This led to cleavage of Caspase-8 and the formation of death-inducing signaling complex (DISC) in lipid rafts. The cholesterol-sequestering agent nystatin partially reversed DR5 clustering and DISC formation, preventing apoptosis triggered by the combination of ß-elemene and TRAIL. Our results suggest that ß-elemene increases the sensitivity of gastric cancer cells to TRAIL partially by promoting the formation of DISC in lipid rafts.

A Clinical Prognostic Score to Predict Survival of Advanced or Metastatic Non-Small Cell Lung Cancer (NSCLC) Patients Receiving First-Line Chemotherapy: A Retrospective Analysis.

BACKGROUND Although several complicated models have been built to evaluate the prognosis of NSCLC patients receiving chemotherapy, simple economic models are still needed to give a preliminary survival assessment of these patients. MATERIAL AND METHODS This study retrospectively assessed the clinical and biological parameters of 223 patients with advanced NSCLC. Univariate and multivariate analyses of overall survival (OS) and progression-free survival (PFS) for the parameters and the prognostic score were assessed. RESULTS Performance status (PS) score=1, smoking history, fibrinogenemia, thrombocytosis, increased lactate dehydrogenase (LDH) level, and anemia were independent predictors of poor prognosis in the univariate analysis of OS and were assessed in multivariate analysis. There was a significant difference in PS=1 (HR=2.134, p<0.0001), increased LDH level (HR=1.508, p=0.014), thrombocytosis (HR=1.547, p=0.012), and smoking history (HR=1.491, p=0.008), based on which the patients were classified into 3 risk groups: low risk (0-1 points), moderate risk (2 points), and high risk (3-5 points). At p values of <0.0001, the median OS was 565, 340, and 273 days and the median progression-free survival was 250, 209, and 135 days, respectively in these 3 risk groups. CONCLUSIONS We established a new prognostic score model using PS, LDH level, PLT count, and smoking history to predict the survival of patients receiving first-line chemotherapy for advanced NSCLC, which might be useful in clinical practice.

Equity and efficiency of medical service systems at the provincial level of China's mainland: a comparative study from 2009 to 2014.

BACKGROUND: The astonishing economic achievements of China in the past few decades have remarkably increased not only the quantity and quality of medical services but also the inequalities in health resources allocation across regions and inefficiency of the medical service delivery. METHODS: A descriptive analysis was used to compare the inequities in inputs and outputs of the provincial medical service systems, a non-radial super-efficiency data envelopment analysis model was then used to estimate the efficiency, and a regression analysis of the panel data was used to explore the determinants. RESULTS: The inputs and outputs of most provincial medical service systems increased gradually from 2009 to 2014. Overall, the eastern region allocated more human and capital resources than the other two regions, and produced more than 50% of the total outpatient and emergency room visits, whereas the western region produced more inpatient services (about 30% of the total volume of inpatient services) according to the distribution of the population. The average efficiency scores of the provincial medical systems in China's mainland were 0.895, 0.927, 0.929, 0.963, 0.977 and 0.968 from 2009 to 2014, with a slight average improvement of 1.60%. The efficiency score of each provincial medical service system varied greatly from one another: Tibet (1.475 ± 0.057) performed extremely well, whereas several others including Heilongjiang (0.579 ± 0.001) performed poorly. Furthermore, the proportion of high-class medical facilities was negatively associated with efficiency, whereas the proportion of the vulnerable population, the per capita Gross Domestic Product, the proportion of the illiterate population and the improvement of primary health care had positive effects on efficiency. CONCLUSION: Inequity in health resources allocation and service provision existed across the regions, but not all the gaps have begun to narrow since 2009. The difference of efficiency was great among provincial medical service systems but minor across regions, and the score changed very little over time. More importantly, the central region held the lowest average efficiency score in the past 6 years, while the western region held the largest average efficiency score at the first 5 years, which should receive enough attention of the government and decision-makers. In practice, efficiency was related to many complicated factors, indicating that the improvement of efficiency is a complex and iterative process that requires the strong cooperation of many sectors.

Increased glycosylation efficiency of recombinant proteins in Escherichia coli by auto-induction.

Escherichia coli cells have been considered as promising hosts for producing N-glycosylated proteins since the successful production of N-glycosylated protein in E. coli with the pgl (N-linked protein glycosylation) locus from Campylobacter jejuni. However, one hurdle in producing N-glycosylated proteins in large scale using E. coli is inefficient glycan glycosylation. In this study, we developed a strategy for the production of N-glycosylated proteins with high efficiency via an optimized auto-induction method. The 10th human fibronectin type III domain (FN3) was engineered with native glycosylation sequon DFNRSK and optimized DQNAT sequon in C-terminus with flexible linker as acceptor protein models. The resulting glycosylation efficiencies were confirmed by Western blots with anti-FLAG M1 antibody. Increased efficiency of glycosylation was obtained by changing the conventional IPTG induction to auto-induction method, which increased the glycosylation efficiencies from 60% and 75% up to 90% and 100% respectively. Moreover, in the condition of inserting the glycosylation sequon in the loop of FN3 (the acceptor sequon with local structural conformation), the glycosylation efficiency was increased from 35% to 80% by our optimized auto-induction procedures. To justify the potential for general application of the optimized auto-induction method, the reconstituted lsg locus from Haemophilus influenzae and PglB from C. jejuni were utilized, and this led to 100% glycosylation efficiency. Our studies provided quantitative evidence that the optimized auto-induction method will facilitate the large-scale production of pure exogenous N-glycosylation proteins in E. coli cells.

Formation of the IGF1R/CAV1/SRC tri-complex antagonizes TRAIL-induced apoptosis in gastric cancer cells.

Lipid rafts provide a biological platform for apoptosis induced by tumor necrosis factor-related apoptosis-inducing ligand (TRAIL). We previously reported that insulin-like growth factor 1 receptor (IGF1R) translocation into lipid rafts helped to explain TRAIL resistance. However, it was not clear whether TRAIL resistance was caused by the interaction of IGF1R with caveolin-1 (CAV1) and the non-receptor tyrosine kinase SRC in lipid rafts of gastric cancer cells. Here, we observed high IGF1R expression in TRAIL-resistant gastric cancer cells, and showed that IGF1R combined with both CAV1 and SRC in a native complex. TRAIL was shown to promote the formation of the IGF1R/CAV1/SRC tri-complex and the activation of these three molecules. Knockdown of IGF1R or CAV1 or inhibition of SRC activity reduced the formation of this tri-complex and enhanced TRAIL-induced apoptosis. Furthermore, the overexpression of microRNA-194 reversed TRAIL resistance by reducing IGF1R expression. In summary, TRAIL increased formation of the IGF1R/CAV1/SRC tri-complex and the activation of downstream survival pathways, leading to TRAIL resistance in gastric cancer cells.

miR-103/107 modulates multidrug resistance in human gastric carcinoma by downregulating Cav-1.

MicroRNAs (miRNAs) are a class of non-protein-coding small RNAs with the capacity to regulate fundamental biological processes essential for cancer initiation and progression. In the present study, we analyzed miRNA expression levels between multidrug-resistant gastric carcinoma cell line SGC7901/ADR and its parent cell line SGC7901 using a miRNA microarray. MiR-103/107 was downregulated compared with parental SGC7901 cells. Overexpression of miR-103/107 sensitized SGC7901/ADR cells to doxorubicin (DOX), as demonstrated by in vitro and in vivo drug sensitivity assay. We further confirmed that miR-103/107 inhibited P-gp function in gastric cancer SGC7901/ADR cells. Finally, we verified that caveolin-1 (Cav-1), a critical component of lipid rafts, was a target of miR-103/107.

Prognostic value of CD133 expression in cancer patients treated with chemoradiotherapy: a meta-analysis.

Many studies evaluated the correlations of CD133 expression with the clinical outcomes in patients treated with chemoradiotherapy (CRT) but yielded controversial results. This meta-analysis was performed to identify the impacts of CD133 expression on the prognosis of cancer patients treated with CRT. Electronic databases updated up to March 2014 were searched to find relevant studies. Relevant literatures without any language restrictions were searched via electronic databases as follows: Web of Science (1945 ~ 2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966 ~ 2013), EMBASE (1980 ~ 2013), CINAHL (1982 ~ 2013), and the Chinese Biomedical Database (CBM) (1982 ~ 2013). STATA software was used for the current meta-analysis. Hazard ratios (HR) and its corresponding 95% confidence interval (95% CI) were calculated. Six studies were identified with a total of 470 cancer patients treated with CRT. The meta-analysis results showed that CD133-positive patients had poorer overall survival (OS) than that of CD133-negative patients (HR = 2.13, 95% CI = 1.20 ~ 3.07, P < 0.001). Furthermore, CD133-positive patients displayed shorter disease-free survival (DFS) than that of CD133-negative patients (HR = 1.74, 95% CI = 0.08 ~ 3.40, P = 0.039). Ethnicity-stratified analysis indicated that CD133 expression positively correlated with shorter OS among the Japanese, Chinese, and Spanish populations (all P < 0.05). In conclusion, our findings suggest that CD133 expression may be positively correlated with poorer prognosis in cancer patients treated with CRT.

Coexpression of c-Met and Notch-1 correlates with poor prognosis in resected non-small-cell lung cancer.

Despite considerable advances in chemotherapy, radiotherapy, target therapy, and biological therapy, the prognosis for those with resected non-small-cell lung cancer (NSCLC) has not substantially improved. It was recently reported that two receptors, Notch-1 and c-Met, correlate directly or indirectly with the initiation and development of malignant tumors, such as lung cancer; however, the prognostic value of coexpression of these receptors and their relationship in resected NSCLC was not clear. In this study, the expression levels of Notch-1 and c-Met in 117 patients with resected NSCLC were assessed using immunohistochemistry (IHC). The results showed that the positive expression rate of Notch-1 in total patients was 59.8 %. The positive expression rate of c-Met in the all population was 69.2 %. In addition, a significant positive association was shown between Notch-1 and c-Met (P < 0.001). Simultaneously, patients with coexpression of both receptors had a significantly poorer prognosis than those without coexpression (P < 0.001). Multivariate analysis showed that T stage (P = 0.016) and c-Met expression (P < 0.001) were independent prognostic factors. In conclusion, coexpression of both receptors correlates with poorer prognosis in patients with resected NSCLC. Targeting both receptors simultaneously may prove a more effective antitumor strategy. Patients with coexpression of both receptors might benefit from cotargeting Notch-1 and c-Met.

Cbl-b accelerates trypsin-induced cell detachment through ubiquitination and degradation of proline-rich tyrosine kinase 2.

Trypsin is a digestive enzyme that is widely used for cell detachment, which is the first stage of tumor metastasis. Recent studies show that adhesion-related kinases are involved in cell detachment. Proline-rich tyrosine kinase 2 (Pyk2) is a crucial kinase in the regulation of cell adhesion and detachment. However, the effect of Pyk2 on cell detachment is controversial. In the present study, we found that Pyk2 expression was rapidly decreased after trypsin treatment in gastric cancer, breast cancer, colon cancer, lung cancer, and human gastric epithelial cells. Knockdown of Pyk2 accelerated cell detachment. Furthermore, lysosome inhibitor NH4CL suppressed cell detachment and increased ubiquitination of Pyk2. Cbl-b is a type of E3 ubiquitin ligase that interacted with Pyk2, reduced the expression of Pyk2, and promoted trypsin-induced degradation of Pyk2. These findings suggest that Cbl-b promoted cell detachment through mono-ubiquitination of Pyk2. Our data provide a new insight into the role of Cbl-b in cell detachment.