Norcantharidin inhibits tumor growth and vasculogenic mimicry of human gallbladder carcinomas by suppression of the PI3-K/MMPs/Ln-5γ2 signaling pathway

BACKGROUND

Vasculogenic mimicry (VM) is a novel tumor blood supply in some highly aggressive malignant tumors. Recently, we reported VM existed in gallbladder carcinomas (GBCs) and the formation of the special passage through the activation of the PI3K/MMPs/Ln-5γ2 signaling pathway. GBC is a highly aggressive malignant tumor with disappointing treatments and a poor prognosis. Norcantharidin (NCTD) has shown to have multiple antitumor activities against GBCs, etc; however the exact mechanism is not thoroughly elucidated. In this study, we firstly investigated the anti-VM activity of NCTD as a VM inhibitor for GBCs and its underlying mechanisms.

METHODS

In vitro and in vivo experiments to determine the effects of NCTD on proliferation, invasion, migration, VM formation, hemodynamic and tumor growth of GBC-SD cells and xenografts were respectively done by proliferation, invasion, migration assays, H&E staining and CD31-PAS double stainings, optic/electron microscopy, tumor assay, and dynamic micro-MRA. Further, immunohistochemistry, immunofluorescence, Western blotting and RT-PCR were respectively used to examine expression of VM signaling-related markers PI3-K, MMP-2, MT1-MMP and Ln-5γ2 in GBC-SD cells and xenografts in vitro and in vivo.

RESULTS

After treatment with NCTD, proliferation, invasion, migration of GBC-SD cells were inhibited; GBC-SD cells and xenografts were unable to form VM-like structures; tumor center-VM region of the xenografts exhibited a decreased signal in intensity; then cell or xenograft growth was inhibited. Whereas all of untreated GBC-SD cells and xenografts formed VM-like structures with the same conditions; the xenograft center-VM region exhibited a gradually increased signal; and facilitated cell or xenograft growth. Furthermore, expression of MMP-2 and MT1-MMP products from sections/supernates of 3-D matrices and the xenografts, and expression of PI3-K, MMP-2, MM1-MMP and Ln-5γ2 proteins/mRNAs of the xenografts were all decreased in NCTD or TIMP-2 group; (all P < 0.01, vs. control group); NCTD down-regulated expression of these VM signaling-related markers in vitro and in vivo.

CONCLUSIONS

NCTD inhibited tumor growth and VM of human GBCs in vitro and in vivo by suppression of the PI3-K/MMPs/Ln-5γ2 signaling pathway. It is firstly concluded that NCTD may be a potential anti-VM agent for human GBCs.

Overexpression of HIF-1α in primary gallbladder carcinoma and its relation to vasculogenic mimicry and unfavourable prognosis

As a novel mode of tumor neovascularization, vasculogenic mimicry (VM) has been reported to increase tumor-related mortality in many different solid tumors. In the present study, two established human gallbladder carcinoma (GBC) cell lines (highly aggressive GBC-SD and poorly aggressive SGC-996) cultured on a three-dimensional matrix were assessed for the ability of VM channel formation under normoxic or hypoxic conditions. In addition, the relationship between HIF-1α gene expression and VM channel formation of GBC cells in vitro was measured using the small interfering RNA (siRNA) technique, western blotting and real-time reverse transcription (RT)-PCR analysis. Furthermore, H&E and CD31/periodic acid-Schiff (PAS) staining were used to observe VM in GBC tissue samples. Additionally, all seventy-one specimens with VM and non-VM were stained for hypoxia inducible factor-1 α (HIF-1α) and its correlation with clinicopathological features and prognosis was analyzed simultaneously. We found that hypoxia could induce more VM channel formation and elevated HIF-1α expression in highly aggressive GBC-SD cells. HIF-1α siRNA efficiently knocked down HIF-1α expression and GBC VM networks under either normoxic or hypoxic conditions. VM was present in human primary GBC and overexpression of HIF-1α was significantly correlated with depth of invasion and perineural involvement in the non-VM group. Moreover, VM and HIF-1α were independent factors for the overall survival of GBC patients and correlated with decreased survival. In conclusion, VM was present in human GBC. As a critical mediator in VM formation, high expression of HIF-1α was associated with VM and tumor progression in GBC patients.

Astrocyte elevated gene-1 overexpression in human primary gallbladder carcinomas: an unfavorable and independent prognostic factor

Astrocyte elevated gene-1 (AEG-1), as an HIV-1 or TNF-α-inducible transcript, is correlated with various aspects of tumor malignancy. However, the status of AEG-1 expression and its clinical significance in human gallbladder carcinoma (GBC) remains unknown. In the present study, we investigated AEG-1 expression in two GBC cell lines (GBC-SD and SGC-996) and GBC tissues by immunohistochemical, Western blot and real-time PCR analysis. We found that AEG-1 was highly expressed in GBC samples (63.4%, 26 of 41) compared with normal gallbladder mucosa (p=0.0003) and highly invasive GBC-SD cell lines at both the protein (p=0.0043) and mRNA levels (p=0.0001), and strongly correlated with differentiation degree (p=0.006), Nevin stage (p=0.0344), Ki-67 expression (p=0.0024) and liver infiltration (p=0.0332) in these patients. Multivariate analysis indicated that AEG-1 overexpression was an independent prognostic marker for GBC patients. Moreover, patients with high AEG-1 levels had shorter survival time (p=0.008). Our results suggest that the AEG-1 protein is a valuable marker of GBC progression and could be a potential therapeutic target.

A simplified model to predict the thermal response of PLG and its influence on BLEVE

A simplified model has been developed to describe the thermal response of pressure liquefied gas (PLG) tanks subjected to fire. The development of the stratification layer is considered in this model. Comparison of results with available experimental data shows that our proposed model can reasonably predict the thermal response. The effect of stratification on the liquid energy is also summarized. Results show that the pressure in the tank rises faster as a result of thermal stratification, and for the same tank pressure the energy in the liquid is less when the liquid is stratified. Stratification can reduce the severity of hazards of boiling liquid expanding vapor explosion (BLEVE).

Cervicovaginal overproduction of specific IgG to human immunodeficiency virus (HIV) contrasts with normal or impaired IgA local response in HIV infection

Paired sera and cervicovaginal secretions (CVS) from 30 women infected with human immunodeficiency virus (HIV) type 1 (before AIDS) were analyzed for IgG and IgA antibodies to HIV and for IgG, IgA, and human serum albumin. Subjects were compared with 30 aged-matched healthy controls. In HIV-infected women, cervicovaginal immunoglobulins were markedly increased, and IgG predominated. An increased immunoglobulin transudation was implicated, since cervicovaginal albumin levels were 2.3-fold above those of normal controls. Furthermore, IgG excretion by reference to albumin was increased 1.9-fold, whereas the IgA secretion tended to decrease, suggesting a possible enhanced local IgG synthesis. Mean IgG and IgA anti-HIV antibody titers were, respectively, 30- and 12-fold higher in serum than in CVS, but their mean specific activities were higher in CVS than in serum, suggesting a local synthesis of both isotypes. The IgA antibody response to HIV remained poor compared with the strong IgG response.

Local synthesis of IgG antibodies to HIV within the female and male genital tracts during asymptomatic and pre-AIDS stages of HIV infection

Paired sera and cervicovaginal secretions or seminal fluids, obtained from HIV-1-infected, clinically asymptomatic women (n = 41) and men (n = 12), were investigated in order to test the hypothesis of a local synthesis of IgG to HIV in the female and male reproductive tracts. Anti-gp41 + p24 IgG was evaluated by an IgG immunocapture assay, and anti-gp160 IgG by an indirect ELISA. Estimation of anti-HIV IgG-specific activities was carried out after ponderal determination of total IgG and evaluation of anti-HIV IgG activity. IgG to gp41 + p24, as well as IgG to gp160, were specifically detected in all sera, cervicovaginal secretions, and seminal fluid samples from all tested HIV-1-infected subjects. The mean specific activities of IgG to gp41 + p24 in cervicovaginal secretions and in seminal fluids were about 33-fold (in women) and 16-fold (in men) that of the corresponding sera; similarly, the mean specific activities of IgG to gp160 in genital secretions were about 17-fold (in women) and 10-fold (in men) that of the corresponding sera. IgGs to HIV are constantly detected in genital secretions from HIV-1-infected subjects, and appear to be largely synthesized in situ within the genital tract of both genders.

Endoscopic variceal ligation. Experience in 78 patients

Endoscopic variceal ligation (EVL) is a new alternative to sclerotherapy in the treatment of esophageal variceal hemorrhage, which results in strangulation, necrosis and scar formation of varices without systemic or local adverse effect. From May 1, 1991 through July 1, 1992, EVL was performed in 78 consecutive patients, in 35 of them it was performed during active massive bleeding, and active bleeding was controlled by the initial session in 31 patients. With repeated EVL treatment, 32 patients had their varices obliterated. The varices had reduced in size in other patients. No ligation-related complications were observed. This procedure is a safe, effective and rather simple method to treat esophageal varices, especially in patients with poor liver function and recurrent bleeding after devascularization or shunt surgery.

Anti-gp160 IgG and IgA antibodies associated with a large increase in total IgG in cervicovaginal secretions from human immunodeficiency virus type 1-infected women

To study the specific local immune response in vaginal fluids, 19 women infected with human immunodeficiency virus (HIV) type 1 and 23 seronegative controls were selected. Vaginal fluids were tested by ELISA for total IgG, IgA, and IgM levels and for specific IgG, IgA, and IgM antibodies to gp160. Total IgG, IgA, and IgM concentrations were 6.8-, 5.0-, and 2.5-fold higher, respectively, in HIV-1-infected women than in controls, with a positive correlation between IgG and IgA levels. IgG or IgA antibodies or both to gp160 were detected in 12 subjects (63%), whereas no IgM antibodies to gp160 were found. Anti-gp160 IgG strongly predominated. Serum samples were available for 11 women whose total IgG vaginal levels strongly correlated with total IgG in sera. These results suggest that transudation of serumborne antibodies is the main source of gp160-specific antibodies in the vaginal fluid of HIV-1-infected women.

[Autogenous vein graft as a conduit for repairing the laryngeal nerve deficit]

Management of recurrent laryngeal nerve (RLN) deficit is a difficult problem and a challenge to surgeons. Effective method for repairing a RLN deficit is not available. Since October 1981, the author has adopted autogenous vein graft as a conduit to repair RLN deficit in 5 cases. All the 5 cases were followed up for more than one year after operation. The results showed that the affected vocal cord movement was entirely or nearly entirely restored in 2 cases, partially restored in 1 case, unrestored in 2 cases, patients phonation was restored to be normal or near normal in 4 cases, including 3 cases with entirely or partially restoration of vocal cord movement and one case with unrestoration of vocal cord movement. The remaining one case had vocal cord movement unrestored, the hoarseness, however was improved significantly. The data suggests that autogenous vein graft as a conduit for repairing RLN deficit is a convincible and an effective method.

[Long-term results of the Hassab operation in portal hypertension: 10 year's follow-up]

Seventy-three patients with portal hypertension who underwent Hassab operation before June 30, 1976 and were alive postoperatively were analysed. Among these patients, portal hypertension was caused by hepatic schistosomiasis in fifty-seven, and by portal cirrhosis in seventeen. According to Child's classification there were 14 in class A, 19 in class B, 30 in class C, and 10 were not classified. Thirty-two patients were subjected to therapeutic operation, forty-one to prophylactic operation. Seventy-one patients were followed-up (97.3%). The postoperative 5, 10 and 15 year cumulative survival rate were 85.5%, 75.8%, and 70.4% respectively. The survival rates in Child A, B patients were much higher than that in Child C patients (P less than 0.05). The postoperative bleeding rate was 11.3%, and the bleeding most often occurred in 1-9 year postoperatively. The esophageal varices disappeared in 64.3% of patients; ascites disappeared in 91.7% of patients; liver function improving or unchanging was seen in 93.6% of patients. There was no postoperative encephalopathy. Long term follow-up showed no difference in patient's survival rate between hepatic schistosomiasis and portal cirrhosis.

Reversal of ischemic liver failure by intrasplenic liver cell transplantation

A model of ischemic hepatic failure in Sprague-Dawley rats (SD) with 100% mortality has been developed by one-hour occlusion of the right portal vein and hepatic artery followed by left 70% hepatectomy. The intrasplenic injection of 40 x 10(6) syngeneic adult or three-day neonatal single liver cell suspensions decreased the mortality from 100% to 50% and 36%, respectively. Mortality decreased with increasing time from the intrasplenic injection of neonatal liver cells to the time of acute hepatic ischemia. Mortality also decreased with increasing interval between hepatic ischemia and removal of the transplanted liver cells by splenectomy. Intrasplenic injection of graded doses of neonatal liver cells decreased mortality from 75% at a dose of 10 x 10(6) cells, to 36% at 160 x 10(6) cells. Treatment of neonatal liver cells with metabolic inhibitors did not significantly affect their ability to reverse acute hepatic ischemia.

Cervical spondylotic myelopathy treated by anterior multilevel decompression and fusion. Follow-up report of 214 cases

From 1974 to 1982, 214 patients were treated for cervical spondylotic myelopathy by anterior multilevel decompression and the Robinson anterior interbody fusion and followed for an average of three years and 11 months. Postoperative results were superior to those obtained previously using posterior decompression. The average patient age was 50.1 years (range, 30-75); there were 187 men and 27 women. Overall, the percent of patients with excellent and good results was 59.3%; with fair results, 29%, no change; 7.9%, and deterioration, 3.8%. Of the 111 patients who had the disease less than one year before treatment, 74% were categorized after surgery as excellent or good. In contrast, only 36% of the 66 patients who had the disease more than two years were rated excellent and good. Myelography is valuable in diagnosing and locating lesions. The average number of discs removed was 3.1 per patient. The number of cases with excellent and good results was the same whether or not union of the graft occurred. Reoperation was required in 12 patients, and a third operation was performed in three patients. Eventually, 93% of the patients were able to lead independent lives.