Gecko Proteins Exert Anti-Tumor Effect against Cervical Cancer Cells Via PI3-Kinase/Akt Pathway

Scorpiones, Scolopendra and Gekko Inhibit Lung Cancer Growth and Metastasis by Ameliorating Hypoxic Tumor Microenvironment via PI3K/AKT/mTOR/HIF-1α Signaling Pathway

OBJECTIVE

To investigate whether Buthus martensii karsch (Scorpiones), Scolopendra subspinipes mutilans L. Koch (Scolopendra) and Gekko gecko Linnaeus (Gekko) could ameliorate the hypoxic tumor microenvironment and inhibit lung cancer growth and metastasis by regulating phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin/hypoxia-inducible factor-1α (PI3K/AKT/mTOR/HIF-1α) signaling pathway.

METHODS

Male C57BL/6J mice were inoculated with luciferase labeled LL/2-luc-M38 cell suspension to develop lung cancer models, with rapamycin and cyclophosphamide as positive controls. Carboxy methyl cellulose solutions of Scorpiones, Scolopendra and Gekko were administered intragastrically as 0.33, 0.33, and 0.83 g/kg, respectively once daily for 21 days. Fluorescent expression were detected every 7 days after inoculation, and tumor growth curves were plotted. Immunohistochemistry was performed to determine CD31 and HIF-1α expressions in tumor tissue and microvessel density (MVD) was analyzed. Western blot was performed to detect the expression of PI3K/AKT/mTOR/HIF-1α signaling pathway-related proteins. Enzyme-linked immunosorbent assay was performed to detect serum basic fibroblast growth factor (bFGF), transforming growth factor-β1 (TGF-β1) and vascular endothelial growth factor (VEGF) in mice.

RESULTS

Scorpiones, Scolopendra and Gekko prolonged the survival time and inhibited lung cancer metastasis and expression of HIF-1α (all P<0.01). Moreover, Scorpiones, Scolopendra and Gekko inhibited the phosphorylation of AKT and ribosomal protein S6 kinase (p70S6K) (P<0.05 or P<0.01). In addition, they also decreased the expression of CD31, MVD, bFGF, TGF-β1 and VEGF compared with the model group (P<0.05 or P<0.01).

CONCLUSION

Scorpiones, Scolopendra and Gekko all showed beneficial effects on lung cancer by ameliorating the hypoxic tumor microenvironment via PI3K/AKT/mTOR/HIF-1α signaling pathway.

Protein extracts from regenerating lizard tail show an inhibitory effect on human cancer cells cultivated in-vitro

BACKGROUND

accumulating evidence indicates that during tail regeneration in lizards the initial stage of regenerative blastema is a tumor-like proliferative outgrowth that rapidly elongates into a new tail composed of fully differentiated tissues. Both oncogenes and tumor-suppressors are expressed during regeneration, and it has been hypothesized that an efficient control of cell proliferation avoids that the blastema is turned into a tumor outgrowth.

METHODS

in order to determine whether functional tumor-suppressors are present in the growing blastema we have utilized protein extracts collected from early regenerating tails of 3-5 mm that have been tested for a potential anti-tumor effect on in-vitro culture by using cancer cell lines from human mammary gland (MDA-MB-231) and prostate cancer (DU145).

RESULTS

at specific dilutions, the extract determines a reduction of viability in cancer cells after 2-4 days of culture, as supported by statistical and morphological analyses. While control cells appear viable, treated cells result damaged and produce an intense cytoplasmic granulation and degeneration.

CONCLUSIONS

this negative effect on cell viability and proliferation is absent using tissues from the original tail supporting the hypothesis that only regenerating tissues synthesize tumor-suppressor molecules. The study suggests that the regenerating tail of lizard at the stages here selected contains some molecules that determine inhibition of cell viability on the cancer cells analyzed.

Strongylopus grayii tadpole blastema extract exerts cytotoxic effects on embryonal rhabdomyosarcoma cells

Amphibians have regenerative capacity and are resistant to developing cancer. This suggests that the developing blastema, located at the tissue regeneration site, may secrete anti-cancer factors. Here, we investigate the anti-cancer potential of tadpole tail blastema extracts (TAD) from the stream frog, Strongylopus grayii, in embryonal rhabdomyosarcoma (ERMS) cells. ERMS originates in skeletal muscle tissue and is a common pediatric soft tissue sarcoma. We show using MTT assays that TAD inhibited ERMS cell viability in a concentration-dependent manner, and phase contrast/fluorescent microscopy revealed that it induced morphological markers of senescence and apoptosis. Western blotting showed that this was associated with DNA damage (γH2AX) and activation of the p38/MAPK stress signaling pathway as well as molecular markers of senescence (p16^INK4a), apoptosis (cleaved PARP), and inhibition of cell cycle promoters (cyclin A, CDK2, and cyclin B1). Furthermore, proteomics followed by gene ontology analyses showed that TAD treatment inhibited known tumor promoters and proteins required for cancer cell survival. Lastly, using the LINCS drug perturbation library, we show that there is an overlap between the proteomics signature induced by TAD and common anti-cancer drugs. Taken together, this study provides novel evidence that TAD exhibits cytotoxicity in ERMS cells.

Reptiles as Promising Sources of Medicinal Natural Products for Cancer Therapeutic Drugs

Natural products have historically played an important role as a source of therapeutic drugs for various diseases, and the development of medicinal natural products is still a field with high potential. Although diverse drugs have been developed for incurable diseases for several decades, discovering safe and efficient anticancer drugs remains a formidable challenge. Reptiles, as one source of Asian traditional medicines, are known to possess anticancer properties and have been used for a long time without a clarified scientific background. Recently, it has been reported that extracts, crude peptides, sera, and venom isolated from reptiles could effectively inhibit the survival and proliferation of various cancer cells. In this article, we summarize recent studies applying ingredients derived from reptiles in cancer therapy and discuss the difficulties and prospective development of natural product research.

Gekkonidae, Lizard tail extracts elicit apoptotic response against non-small cell lung cancer via inhibiting Akt signaling

The genes of Gekkonidae, a lizard, are known to be very similar to human genes. According to previous research, lizard extracts inhibit angiogenesis and show anticancer activity against various cancers. In this regard, this study assessed whether lizard tail extracts (LTE) cause anticancer activity against lung cancer in mouse and human lung cancer cell lines. The results showed that LTE exhibited anticancer activity against lung cancer in vitro and in vivo. In vitro, cell viability and proliferation decreased in two lung cancer cell lines, while annexin V and single-stranded DNA both increased, showing apoptotic activity caused by LTE. We also found that LTE induced apoptosis in a caspase-3/7 cascade-dependent manner and inhibited the phosphorylation of Akt by participating in the PI3k/Akt pathway. In vivo, LTE decreased tumor volume in LLC bearing mice. Our results demonstrate the potential of LTE as a natural-derived anticancer drug to overcome the chemotherapy side effects during cancer treatment and contribute to the discovery of candidate substances.

Spot the difference: Solving the puzzle of hidden pictures in the lizard genome for identification of regeneration factors

All living things share some common life processes, such as growth and reproduction, and have the ability to respond to their environment. However, each type of organism has its own specialized way of managing biological events. Genetic sequences determine phenotypic and physiological traits. Based on genetic information, comparative genomics has been used to delineate the differences and similarities between various genomes, and significant progress has been made in understanding regenerative biology by comparing the genomes of a variety of lower animal models of regeneration, such as planaria, zebra fish, and newts. However, the genome of lizards has been relatively ignored until recently, even though lizards have been studied as an excellent amniote model of tissue regeneration. Very recently, whole genome sequences of lizards have been uncovered, and several attempts have been made to find regeneration factors based on genetic information. In this article, recent advances in comparative analysis of the lizard genome are introduced, and their biological implications and putative applications for regenerative medicine and stem cell biology are discussed. [BMB Reports 2016; 49(5): 249-254]

Gecko proteins induce the apoptosis of bladder cancer 5637 cells by inhibiting Akt and activating the intrinsic caspase cascade

Gecko proteins have long been used as anti-tumor agents in oriental medicine, without any scientific background. Although anti-tumor effects of Gecko proteins on several cancers were recently reported, their effect on bladder cancer has not been investigated. Thus, we explored the anti-tumor effect of Gecko proteins and its cellular mechanisms in human bladder cancer 5637 cells. Gecko proteins significantly reduced the viability of 5637 cells without any cytotoxic effect on normal cells. These proteins increased the Annexin-V staining and the amount of condensed chromatin, demonstrating that the Gecko proteinsinduced cell death was caused by apoptosis. Gecko proteins suppressed Akt activation, and the overexpression of constitutively active form of myristoylated Akt prevented Gecko proteins-induced death of 5637 cells. Furthermore, Gecko proteins activated caspase 9 and caspase 3/7. Taken together, our data demonstrated that Gecko proteins suppressed the Akt pathway and activated the intrinsic caspase pathway, leading to the apoptosis of bladder cancer cells. [BMB Reports 2015; 48(9): 531-536].

Anti-angiogenic activity of gecko aqueous extracts and its macromolecular components in CAM and HUVE-12 cells

Gecko is a kind of traditional Chinese medicine with remarkable antineoplastic activity. However, undefined mechanisms and ambiguity regarding active ingredients limit new drug development from gecko. This study was conducted to assess anti-angiogenic properties of the aqueous extracts of fresh gecko (AG) or macromolecular components separated from AG (M-AG). An enzyme-linked immunosorbent assay (ELISA) approach was applied to detect the vascular endothelial growth factor (VEGF) secretion of the tumor cells treated with AG or M-AG. The effect of AG or M-AG on vascular endothelial cell proliferation and migratory ability was analyzed by tetrazolium dye colorimetric method, transwell and wound-healing assays. Chick embryo chorioallantoic membrane (CAM) assays were used to ensure the anti-angiogenic activity of M-AG in vivo. The results showed that AG or M-AG inhibited the VEGF secretion of tumor cells, the relative inhibition rates of AG and M-AG being 27.2% and 53.2% respectively at a concentration of 20 μL/mL. AG and M-AG inhibited the vascular endothelial (VE) cell proliferation with IC50 values of 11.5 ± 0.5 μL/mL and 12.9 ± 0.4 μL/mL respectively. The VE cell migration potential was inhibited significantly (p<0.01) by the AG (≥ 24 μL/mL) or M-AG (≥ 12 μL/ mL) treatment. In vivo, neovascularization of CAM treated with M-AG was inhibited significantly (p<0.05) at a concentration of 0.4 μL/mL. This study provided evidence that anti-angiogenesis is one of the anti-tumor mechanisms of AG and M-AG, with the latter as a promising active component.

Differentiation of bel-7402 human hepatocarcinoma cells induced by aqueous extracts of fresh gecko (AG) and its anti-tumor activity in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Gecko, a kind of reptile, has been widely used as a traditional Chinese medicine to treat various diseases including cancer in China for thousands of years. The aim of this study was to investigate the anti-tumor effect of AG (aqueous extracts of fresh gecko) on human hepatocellular carcinoma cell Bel-7402 in vitro and mouse H22 hepatocellular in vivo. Further to underlie the molecular mechanism of AG inducing the differentiation of Bel-7402 cells.

MATERIALS AND METHODS

AG was obtained by water extracting method and qualitatively analyzed through High Performance Liquid Chromatography. The total protein concentration of AG was measured by BCA (bicinchoninic acid disodium) assay. The anti-tumor activities in vivo were analyzed through H22 (mouse hepatocellular carcinoma cell line H22) tumor xenografts mice. The cytotoxic activity of AG on Bel-7402 cells was evaluated by MTT assays. AFP (alpha fetoprotein) was detected by radioimmunoassay. ALB (albumin), ALP (alkaline phosphatase) and γ-GT (γ-glutamyl transpeptidase) were detected by biochemical methods with commercial kits. While morphological changes were observed through an inverted microscope. Moreover, the expression level of the proteins involved in MAPK (mitogen-activated protein kinase) signal pathway which was closely related to cellular differentiation was assessed by Western blot.

RESULTS

AG showed obviously anti-tumor activity in vivo and anti-proliferative activity on Bel-7402 cells in vitro both dose-dependently. The number of clones of Bel-7402 cells treated with AG reduced and the cells were displaying differentiation state such as relatively bigger size and dispersed growth. The biochemical function markers of the cells were significantly changed after being treated with AG. The data showed that AFP secretion of the cells decreased 42.5%, ALB secretion increased 58.9%, the activity of ALP and γ-GT markedly decreased 67.0% and 48.5% separately when the concentration of AG was 10μl/ml, and those effects were all in a dose-dependent manner. The major original and phosphorylated signal proteins (ERK1/2 (extracellular sigal-regualted kinase 1/2), P38 (p38 MAPK) and JNK1/2 (c-Jun N-terminal kinase 1/2)) involved in MAPK signal pathway were measured and the results showed that AG activated the ERK1/2 of Bel-7402 cells.

CONCLUSIONS

AG has anti-tumor activity in vivo and inhibits Bel-7402 cell proliferation in vitro through inducing cell differentiation, and the mechanism involves the activation of ERK1/2.