[Mechanism of Polypeptide Extract from Scorpion Venom Combined Rapamycin in Enhancing Autophagy of H22 Hepatoma Cells: an Experimental Study].

OBJECTIVE: To observe enhanced effects of polypeptide extract from scorpion venom (PESV) combined Rapamycin on autophagy of H22 hepatoma cells in mice and to explore its possible mechanism. METHODS: The H22 hepatocarcinoma cell suspension was subcutaneously inoculated into 40 Kunming mice. Then tumor-bearing mice were randomly divided into four groups, i.e., the control group,the high dose PESV group, the low dose PESV group, and the combination group (high dose PESV + Rapamycin), 10 in each group. Mice in high and dose PESV groups were administered with 20 mg/kg and 10 mg/kg PESV respectively by gastrogavage. Mice in the combination group were administered with 2 mg/kg rapamycin and 20 mg/kg PESV by gastrogavage. The intervention lasted for 14 successive days. The tumor volume was measured once every other day, the tumor growth curve was drawn, and then the tumor inhibitory rate calculated. Pathological changes of the tumor tissue were observed by HE staining. Protein expression levels of mammal target of rapamycin (mTOR), UNC-51-like kinase-1 (ULK1), microtubule-associated protein1 light chain3 (MAPILC3A), and Beclin1 were detected by immunohistochemical assay. RESULTS: The growth of H22 hepatoma transplantation tumor was inhibited in high and low dose PESV groups and the combination group (P < 0.05). And there was statistical difference in tumor weight and tumor volume between the combination group and high and low dose PESV groups (P < 0.05). There was no statistical difference in tumor weight or tumor volume between the high dose PESV group and the low dose PESV group (P > 0.05). lmmunohistochemical assay showed that the protein expression of mTOR was higher, but protein expressions of ULK1, MAP1LC3A, Beclin1 were lower in the control group than in the rest 3 groups (P < 0.05, P < 0.01). Compared with the high dose PESV group, protein expressions of ULK1, MAP1LC3A, and Beclin1 were obviously lower (P < 0.05). CONCLUSION: PESV combined Rapamycin might inhibit the development of H22 hepatoma transplantation tumor in mice possibly through inhibiting the activity of mTOR, enhancing expressions of ULK1, MAP1LC3A, and Beclin1.

[Study on the mechanism of polypeptide extract from scorpion venom on inhibition of angiogenesis of H 22 hepatoma].

OBJECTIVE: To explore the mechanism of polypeptide extract from scorpion venom (PESV) on inhibiting angiogenesis. METHODS: The H22 hepatoma tumor model was established by subcutaneously implanting H22 hepatoma cells into mice. The tumor-bearing mice were randomly divided into 4 groups, i.e., the control group, the high dose PESV group, the low dose PESV group, and the 5-fluorouracil (5-Fu) group, 10 mice in each group. The intervention was lasted for 14 days. The growth curve of the tumor volume was drawn and the inhibition rate calculated. Pathological changes of the tumors were observed by HE staining. The microvessel density (MVD) was detected using SP method. The protein expression levels of phosphatidylinositol 3-kinase (P13K), phosphoprotein kinase B (P-Akt), hypoxia-inducible factor-1 alpha (HIF-1 )alpha, and vascular endothelial growth factor-A (VEGF-A) were detected by immunohistochemical assay and Western blot. RESULTS: The tumor inhibitory rate was 64.8%, 43.7%, and 32.4% in the 5-Fu group, the high dose PESV group, and the low dose PESV group. Compared with the control group, the protein expression of PI3K, P-Akt, HIF-1alpha, and VEGF-A were obviously inhibited by PESV and 5-Fu (P <0. 05,P <0. 01). The MVD also decreased in the high and low dose PESV groups (P < 0.05). CONCLUSIONS: PESV could inhibit the angiogenesis of H22 hepatoma. The mechanisms might be associated with suppressing the expression of PI3K, P-Akt, HIF-1 alpha, and VEGF-A.

[Research on the effect and mechanism of polypeptide extract from scorpion venom combined with 5-fluorouracil on vasculogenic mimicry of H22 hepatoma].

OBJECTIVE: To observe the inhibition effects of polypeptide extract from scorpion venom (PESV) combined 5-fluorouracil (5-Fu) on vasculogenic mimicry (VM) of H2 hepatoma carcinoma cells in mice and its possible mechanisms. METHODS: The H22 carcinoma cell suspension was subcutaneously inoculated into 60 Kunming mice. Then tumor-bearing mice were randomly divided into three groups, i.e., the control group, the 5-Fu group, and the combination group (PESV +5-Fu), 20 in each group. The tumor volume was measured once every other day after 14 successive days of intervention. Then the tumor volume growth curve was drawn, and the tumor inhibitory rate was calculated. The morphological changes of the tumor tissue were observed by HE staining. The VM density of each tumor tissue were detected by immunohistochemical assay and periodic acid-schiff stain (PAS). The protein expression levels of hypoxia inducible factor-la (HIF-la) and matrix metalloproteinase-2 (MMP-2) were detected using immunohistochemical assay. The gray value was semi-quantitatively analyzed using LeicaQwinV3 Image Analysis Software. RESULTS: The growth of H22 hepatoma transplantation tumor was inhibited more obviously in the combination group and the 5-Fu group than in the control group (P <0.05). There was statistical difference in the tumor weight and the tumor volume between the combination group and the 5-Fu group (P <0.05). Immunohistochemical assay and PAS showed that the VM density was obviously lower in the combination group than in the control group and the 5-Fu group (P <0.01). Compared with the control group, the protein expressions of HIF-la and MMP-2 significantly decreased in the combination group (P <0.01). CONCLUSIONS: PESV combined 5-Fu could inhibit the generation of VM of H22 hepatoma transplantation tumor in mice. Its mechanisms might be associated with inhibiting the expressions of HIF-lalpha and MMP-2 in the microenvironment of tumors.

[Study on the mechanism of polypeptide extract from scorpion venom to promote the restraint of cyclophosphamide on Lewis lung cancer].

OBJECTIVE: To explore the mechanism of polypeptide extract from scorpion venom (PESV) on promoting anti-tumor effects of cyclophosphamide (CTX). METHODS: The Lewis lung tumor model was established by subcutaneously implanting Lewis lung cells into C57BL/6 mice. The tumor-bearing mice were randomly divided into 4 groups, i. e., the model group, the cyclophosphamide (CTX) group, the polypeptide extract from scorpion venom (PESV) group, and the combination group (CTX + PESV), 10 mice in each group. The tumor growth curve was recorded. Changes of vascular endothelial growth factor-A (VEGF-A) and transforming growth factor-beta1 (TGF-beta1) expressions in the tumor microenvironment were detected using reverse transcription PCR and immunohistochemical assay. Changes of dendritic cells (DCs) phenotype CD80 and CD86 expressions in the tumor tissue were detected using immunofluorescence chemical assay. RESULTS: After 21 successive days of treatment, the growth of Lewis lung cancer transplantation tumor in the combination group was obviously inhibited (P<0.05). Compared with the model group,the expressions of CD80 and CD86 in the PESV group was somewhat enhanced, while those in the CTX group was somewhat lowered. Compared with the CTX group, the fluorescent signal strength and expressions in the combination group somewhat increased. Compared with the model group, the expressions of TGF-beta1 and VEGF-A mRNA decreased in the PESV group and the CTX group (both P<0.05). Compared with the PESV group and the CTX group, the expressions of TGF-beta1 and VEGF-A in the combination group both decreased (both P<0.05). CONCLUSION: PESV could inhibit the expressions of VEGF and TGF-beta1, promote the maturation of DCs, recover its antigen uptake presentation function, and reverse the immune injury to the body by CTX, thus playing a role in inducing the tumor cell apoptosis.

Anti-proliferation Effect of Polypeptide Extracted from Scorpion Venom on Human Prostate Cancer Cells in vitro.

BACKGROUND: Prostate cancer is a major cause of cancer-related death in men. Therefore there has been considerable interest to explore neoadjuvant therapy. Polypeptide extracted from scorpion venom (PESV), originally obtained from the East-Asian scorpion Buthus martensi Karsch (BmK), is being studied for both prevention and treatment of various human malignancies including prostate cancer. METHODS: The present study was to investigate the effect of PESV on cell proliferation, cell cycle, and apoptosis in human androgen-independent prostate cancer cells DU-145 in vitro. RESULTS: PESV treatment on these cells resulted in a significantly dose-dependent growth inhibition with a G1 phase arrest at 40µg/mL after 48h treatment. PESV treatment strongly induced expression of p27 (Kip1), but resulted in a decrease in cyclin E, one of cyclins involved in G1 progression. In other studies, PESV treatment also induced high apoptosis index (AI), confirmed by TdTmediated dUTP-biotin nick-end labeling (TUNEL) assay. Further, the apoptosis induction by PESV (40µg/mL) in DU145 cells was associated with an increase of pro-apoptotic protein Bax. CONCLUSIONS: These results suggest that PESV modulates the expression of cell cycle-related and apoptosis-related proteins and induces growth inhibition and apoptosis of DU145 cells, providing a strong rationale for future studies to evaluate prevention or/and intervention strategies for PESV in pre-clinical prostate cancer models. KEYWORDS: Prostate cancer, PESV, cell proliferation, cell cycle, apoptosis.

Clinical Trials of Antiangiogenesis Therapy on Gastric Cancer.

Both malignant tumor growth and metastasis are dependent upon angiogenesis, a process of new blood vessel formation. Inhibition of this process by specific inhibitors might be able to control tumor growth and metastasis. Therefore, antiangiogenesis thereapy is considered a promising strategy and being studied worldwide. A wide variety of angiogenesis inhibitors have been identified and some of them are under clinical trials in the advanced patients with cancer including gastric cancer. This review summarizes the development and progress of angiogenesis inhibitors in recent decades, and discusses the future direction of antiangiogenesis research, and the potential antiangiogenic agents which are most likely to be translated into standard treatment for gastrointestinal cancer patients either alone or combined with other therapies.