Exogenous H2S promotes cancer progression by activating JAK2/STAT3 signaling pathway in esophageal EC109 cells.

Hydrogen sulfide (H2S) plays an important role in diverse physiological and pathophysiological processes in cancer cells both in vitro and in vivo. We have previously shown that exogenous H2S exerts its biological effects on hepatoma, glioma, and esophageal cancer cells through the activation of NF-κB, p38-MAPK/ERK1/2-COX-2, and HSP90 pathways. However, the role of H2S and the underlying mechanism in esophageal squamous cell carcinoma remain unclear. Here we investigated whether exogenous H2S contributes to the biological behavior of esophageal squamous cancer cell line EC109, through the activation of JAK2/STAT3 signaling pathway. EC109 cells were treated with NaHS (a donor of H2S) and AG490 (a specific inhibitor of JAK2/STAT3 signaling pathway). The expression levels of p-JAK2, p-STAT3, caspase-3/9/12, Bax, Bcl-2, MMP-2/9, and VEGFR were measured by western blot analysis. Cell viability was detected by CCK-8 and quantified by direct counting of cells under a microscope. Cell migration was analyzed by the scratch-wound assay, while the level of VEGF was measured by ELISA. Cells treated with NaHS for 24 h showed significant upregulation of p-JAK2, and p-STAT3 expression, as well as increased cell viability when compared to the control cells. The expression levels of caspase-3/9/12 and Bax decreased, while those of Bcl-2, MMP-2/9, VEGFR, and VEGF increased. NaHS induced the migration of EC109 cells. However, co-treatment with NaHS and AG490 significantly inhibited these effects. Thus, JAK2/STAT3 signaling pathway may contribute to H2S-induced cell proliferation, anti-apoptosis, migration, and angiogenesis in EC109 cells.

Midkine is a serum and urinary biomarker for the detection and prognosis of non-small cell lung cancer.

Midkine, a heparin-binding growth factor, has been identified as a promising cancer biomarker. In non-small cell lung cancer (NSCLC), the serum and urine midkine levels have not been intensively investigated. The aim of the present study was to investigate the diagnostic and prognostic potential of serum and urine midkine levels in patients with NSCLC. The serum midkine levels were measured in 153 patients with NSCLC, 23 patients with benign pulmonary disease and 95 healthy controls using ELISA. Urine midkine levels were examined in 20 controls and 45 patients with NSCLC. Midkine expression in tumor tissues from 72 patients with NSCLC who underwent definitive surgical resection without any pre-operative treatments was examined by immunohistochemistry. Serum levels were significantly higher in patients with NSCLC than in healthy controls (657.36±496.58 pg/ml vs. 194.49±122.57 pg/ml, P<0.001). As shown in the ROC curve analysis, the sensitivity and specificity of the cut-off serum midkine concentration of 400 pg/ml for predicting the presence of NSCLC were 71.2% and 88.1%, respectively. Positive correlations between the serum midkine levels and immunohistochemistry staining scores (r=0.315, P=0.007) and between the serum midkine levels and urine midkine levels (r=0.636, P<0.001) were observed using Spearman's bivariate correlations. The serum midkine concentration was identified as an independent prognostic factor by multivariate analysis, and its overexpression yielded a relative risk of death of 2.072 (0.01.

Synthesis of acyl oleanolic acid-uracil conjugates and their anti-tumor activity.

BACKGROUND: Oleanolic acid, which can be isolated from many foods and medicinal plants, has been reported to possess diverse biological activities. It has been found that the acylation of the hydroxyl groups of the A-ring in the triterpene skeleton of oleanolic acid could be favorable for biological activities. The pyrimidinyl group has been constructed in many new compounds in various anti-tumor studies. RESULTS: Five acyl oleanolic acid-uracil conjugates were synthesized. Most of the IC50 values of these conjugates were lower than 10.0 µM, and some of them were even under 0.1 µM. Cytotoxicity selectivity detection revealed that conjugate 4c exhibited low cytotoxicity towards the normal human liver cell line HL-7702. Further studies revealed that 4c clearly possessed apoptosis inducing effects, could arrest the Hep-G2 cell line in the G1 phase, induce late-stage apoptosis, and activate effector caspase-3/9 to trigger apoptosis. CONCLUSIONS: Conjugates of five different acyl OA derivatives with uracil were synthesized and identified as possessing high selectivity toward tumor cell lines. These conjugates could induce apoptosis in Hep-G2 cells by triggering caspase-3/9 activity.Graphical abstractFive acyl oleanolic aicd-uracil conjugates were synthesized. These conjugates exhibited selective cytotoxicity toward tumor cells achieved via inducing apoptosis by activation of caspase-3/9.

Preoperative serum fibrinogen is an independent prognostic factor in operable esophageal cancer.

In order to fully elucidate the association between serum fibrinogen and prognosis of esophageal cancer, we examined serum fibrinogen concentrations in 1512 patients who underwent esophagectomy by the Clauss method. The impact of fibrinogen on overall survival and disease-free survival was analyzed using the Kaplan-Meier method and Cox proportional hazard models. Hyperfibrinogenemia was significantly associated with older age, male gender, smoking, alcohol consumption, weight loss, advanced pathological T stage and lymph node metastasis. Patients with hyperfibrinogenemia exhibited poor OS (HR=1.20, 95%CI: 1.04-1.38, P=0.012) and DFS (HR=1.18, 95%CI: 1.03-1.35, P=0.019). Subgroup analysis further exhibited an significant association between hyperfibrinogenemia and poor OS (P<0.001), DFS (P<0.001) in esophageal squamous cell carcinoma (P<0.001) and early pathological stage (I-II) (P=0.001). Collectively, this study indicates that preoperative serum fibrinogen is an independent prognostic factor for survival in esophageal cancer.

Conjugation of Uridine with Oleanolic Acid Derivatives as Potential Antitumor Agents.

According to fused two bioactive moieties together by bonds covalently and available as a new single hybrid entity known as pharmacophore hybridization, a total of 10 targeted uridine-oleanolic acid hybrids were synthesized. Most of these hybrids showed excellent proliferation inhibition against tested Hep-G2, A549, BGC-823, MCF-7, and PC-3 tumor cell lines (IC50 < 8 µm), even with some IC50 values under 0.1 µm. The detection of cytotoxicity selectivity revealed that hybrids 5 and 18 exhibited low cytotoxicity toward normal human liver cell HL-7702. Further studies revealed that selected hybrid 5 could induce apoptosis in Hep-G2 cells through the investigation of acridine orange/ethidium bromide, Hoechst 33258 fluorescence stainings, and annexin V/propidium iodide assay. It was also found that hybrid 5 could induce mitochondrial membrane potential disruption, arrest Hep-G2 cell line at G1 phase, and activate effector caspase-3/9 to trigger cell apoptosis.

Synthesis of oleanolic acid dimers linked at C-28 and evaluation of anti-tumor activity.

Five dimeric oleanolic acids linked at C-28 by 1,6-hexanediamine, or built around the carbon chains of varying lengths between two carboxyl groups were synthesized, to investigate the effect of internal spacer length and species upon the stereochemical features and anti-tumor activity of the resultant bis-oleanolic acids. The IC50 values of these dimeric compounds for cytotoxicity evaluation in vitro against Hep-G2, A549, BGC-823, MCF-7 and PC-3 tumor cell lines, were mainly under 10.0 µM. This result was much better than the inhibition of proliferation against tested tumor cell lines of the monomer oleanolic acid and the commercial anticancer drug 5-fluorouracil. The cytotoxicity selectivity detection revealed that dimer 11c exhibited low cytotoxicity towards normal human liver cell HL-7702. A combination of fluorescence staining observation and flow cytometric analysis indicated that 11c could induce Hep-G2 cell apoptosis. Molecular mechanism studies suggested that 11c induced apoptosis is mediated through the intrinsic apoptotic pathway with changes in mitochondrial membrane potential by finally activating effector caspase-3/9 to trigger cell apoptosis. Further studies revealed that 11c caused cell cycle arrest at G1 phase in Hep-G2 cells. Taken together, these results suggest that 11c may be a potential candidate for further cancer research.

[Several changes of Indocalamus leaf active ingredients contents].

In this paper, the leaves of Indocalamus herklotsii, Indocalamus decorus, and Indocalamus latifolius were collected from Nanjing in different seasons to study the seasonal changes of the total flavonoids, tea polyphenols, and soluble sugar contents in the leaves. There existed significant differences in the test active ingredients contents among the leaves of the three Indocalamus species. The leaf total flavonoids content of the three Indocalamus species in different seasons ranged in 1.7%-2.7%, being the highest for I. herklotsii and I. decorus in spring and for I. latifolius in winter. The leaf tea polyphenols content varied from 5.5% to 7.6%; and the leaf soluble sugar content was 1.0%-8.5%, with the maximum in spring. Within the three months after leaf unfolding, the active ingredients contents in I. herklotsii and I. decorus leaves increased with leaf age. The optimal period for harvesting Indocalamus leaves was from December to next March. Among the three Indocalamus species, I. latifolius had the highest contents of the three active ingredients in leaves, suggesting that I. latifolius had greater potential value in the utilization of its leaf active ingredients than the other two species.

[Notch1 expression in esophageal squamous cell carcinoma and its relation with microvascular angiogenesis].

OBJECTIVE: To observe Notch1 expression in esophageal squamous cell carcinoma (ESCC) and investigate its relation with microvascular angiogenesis in the tumor. METHODS: Tissue slices of 40 cases ESCC (cancer group) and 8 cases normal esophagus tissues (normal group) were obtained to analyze the expression of Notch1 and vascular endothelial growth factor (VEGF) using immunohistochemistry and estimate the microvessel density (MVD) in the tumor. RESULTS: Notch1 expression was significantly lower in the cancer group than in the normal group (P<0.05). In the cancer group, Notch1 expression was higher in highly differentiated than in poorly differentiated tumors (P<0.05) regardless of tumor infiltration or lymph nodes metastasis (P>0.05). VEGF expression and MVD were significantly higher in cancer group than in normal group, and showed significant differences between tumors with different differentiation degrees, infiltration and lymph node metastasis (P<0.05). Correlation analysis showed that Notch1 expression was inversely correlated to VEGF expression. CONCLUSION: Notch1 may be an anti-oncogene in ESCC and affects cell differentiation in early stage of the malignancy. Abnormally low expression of Notch1 in ESCC may be one of the upstream factors to induce high expression of VEGF and increased MVD. The Notch1 pathway might play a key role in microvascular angiogenesis in ESCC.