Effects of Gekko sulfated polysaccharide-protein complex on the defective biorheological characters of dendritic cells under tumor microenvironment. Cell Biochem Biophys. 2012;62:193-201. [PMID: 21913004 DOI: 10.1007/s12013-011-9282-5]

A Water Polysaccharide-Protein Complex from Grifola frondosa Inhibit the Growth of Subcutaneous but Not Peritoneal Colon Tumor under Fasting Condition

SCOPE

Grifola frondosa has been shown to induce immune modulatory, modulate autophagy, and apoptosis in cancer cells. However, little is known about its potential for managing tumor progression as an adjunct to nutrient restriction.

METHODS AND RESULTS

Water extract produces a G. frondosa polysaccharide-protein complex (G. frondosa PPC) of average molecular weight of 46.48 kDa, with glucose (54.8%) as the main constituent. Under serum-restricted conditions, G. frondosa PPC can significantly inhibit MC38 colorectal tumor cell migration in vitro. Under alternate-day fasting condition, G. frondosa PPC can only significantly inhibit the growth of subcutaneous (s.c.) tumor, but is feeble in halting its spread in the intraperitoneal (i.p.) cavity in tumor-bearing mice. Histopathological examination and Raman imaging show a significant increase in lipid content in the tumor microenvironment (TME) tissue of the s.c. tumor-bearing mice. G. frondosa PPC significantly increases C17:0 and C24:0 saturated fatty acids and significantly decreases C16:1 and C18:1 monounsaturated fatty acids in the TME of s.c. tumor-bearing mice compared with the i.p. cavity model.

CONCLUSION

G. frondosa PPC significantly inhibits tumor growth in s.c. tumor-bearing mice under intermittent fasting conditions by altering the fatty acid composition of the TME.

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.

Sulfated Galactans from Red Seaweed Gracilaria fisheri Target EGFR and Inhibit Cholangiocarcinoma Cell Proliferation

Cholangiocarcinoma (CCA) is increasing in incidence worldwide and is resistant to chemotherapeutic agents, making treatment of CCA a major challenge. Previous studies reported that natural sulfated polysaccharides (SPs) disrupted growth factor receptor activation in cancer cells. The present study, therefore, aimed at investigating the antiproliferation effect of sulfated galactans (SG) isolated from the red seaweed Gracilaria fisheri (G. fisheri) on CCA cell lines. Direct binding activity of SG to CCA cells, epidermal growth factor (EGF) and epidermal growth factor receptor (EGFR) were determined. The effect of SG on proliferation of CCA cells was investigated. Cell cycle analyses and expression of signaling molecules associated with proliferation were also determined. The results demonstrated that SG bound directly to EGFR. SG inhibited proliferation of various CCA cell lines by inhibiting EGFR and extracellular signal-regulated kinases (ERK) phosphorylation, and inhibited EGF-induced increased cell proliferation. Cell cycle analyses showed that SG induced cell cycle arrest at the G0/G1 phase, down-regulated cell cycle genes and proteins (cyclin-D, cyclin-E, cdk-4, cdk-2), and up-regulated the tumor suppressor protein P53 and the cyclin-dependent kinase inhibitor P21. Taken together, these data demonstrate that SG from G. fisheri inhibited proliferation of CCA cells, and its mechanism of inhibition is mediated, to some extent, by inhibitory effects on EGFR activation and EGFR/ERK signaling pathway. SG presents a potential EGFR targeted molecule, which may be further clinically developed in a combination therapy for CCA treatment.

Tumor Microenvironment as a New Target for Tumor Immunotherapy of Polysaccharides

Many researches show that polysaccharides derived from fungi and plants have strong pharmacological activities such as enhancing the organism immune and anti-tumor function, and have few toxic and side effects. So the polysaccharides show a wide application prospect in the prevention and therapy of tumor. The tumor microenvironment consists of tumor cells and tumor cells' surrounding environment. The tumor microenvironment not only plays a key role in the development of tumor, but also is a potential treasure for searching new ways to treat tumor. In this review, we summarized polysaccharides' regulation effects on tumor microenvironment progression and tried to give a new theoretical basis for the exploitation of polysaccharides with anti-tumor activity.

Sulfated polysaccharide-protein complex sensitizes doxorubicin-induced apoptosis of breast cancer cells in vitro and in vivo

The present study aimed to investigate the effect of sulfated polysaccharide-protein complex (SPPC) on the antitumor effect of doxorubicin (Dox) on MDA-MB-231 breast cancer cells in vitro and in vivo. MTT and Annexin V/propidium iodide staining assays demonstrated that SPPC selectively sensitized MDA-MB-231 cells to Dox-induced cytotoxicity. The half maximal inhibitory concentration of Dox against MDA-MB-231 cells was decreased from 5.3 to 1.5 µM when it was used concomitantly with 5 µM SPPC. SPPC potentiated Dox-induced apoptosis in breast cancer cells via the mitochondrial apoptosis signaling pathway by activating caspase-3 and caspase-9. Notably, the caspase inhibitor Z-VAD-fmk diminished the effect of SPPC on Dox-mediated apoptosis. Furthermore, combination treatment with SPPC and Dox markedly reduced the growth of breast cancer xenografts in mice. The present study demonstrated that SPPC was able to enhance the antitumor effect of Dox on breast cancer cells, thus suggesting that SPCC may be used to reduce the cumulative dose of Dox and its associated toxicities in the chemotherapy of breast cancer and other types of cancer.

Preventive and Therapeutic Effects of Chinese Herbal Compounds against Hepatocellular Carcinoma

Traditional Chinese Medicines, unique biomedical and pharmaceutical resources, have been widely used for hepatocellular carcinoma (HCC) prevention and treatment. Accumulated Chinese herb-derived compounds with significant anti-cancer effects against HCC have been identified. Chinese herbal compounds are effective in preventing carcinogenesis, inhibiting cell proliferation, arresting cell cycle, inducing apoptosis, autophagy, cell senescence and anoikis, inhibiting epithelial-mesenchymal transition, metastasis and angiogenesis, regulating immune function, reversing drug resistance and enhancing the effects of chemotherapy in HCC. This paper comprehensively reviews these compounds and their effects on HCC. Finally, the perspectives and rational application of herbal compounds for HCC management are discussed.

Traditional Chinese medicine for prevention and treatment of hepatocarcinoma: From bench to bedside

Traditional Chinese medicine (TCM) has played a positive role in the management of hepatocarcinoma. Hepatocarcinoma patients may present Qi-stagnation, damp-heat, blood stasis, Qi-deficiency, Yin-deficiency and other TCM syndromes (Zheng). Modern treatments such as surgery, transarterial chemoembolization (TACE) and high intensity focus ultrasound treatment would influence the manifestation of TCM syndromes. Herbs with traditional efficacy of tonifying Qi, blood and Yin, soothing liver-Qi stagnation, clearing heat and detoxifying and dissolving stasis, have been demonstrated to be potent to prevent hepatocarcinogenesis. TCM has been widely used in all aspects of integrative therapy in hepatocarcinoma, including surgical resection, liver transplantation, TACE, local ablative therapies and even as monotherapy for middle-advanced stage hepatocarcinoma. Clinical practices have confirmed that TCM is effective to alleviate clinical symptoms, improve quality of life and immune function, prevent recurrence and metastasis, delay tumor progression, and prolong survival time in hepatocarcinoma patients. The effective mechanism of TCM against hepatocarcinoma is related to inducing apoptosis, autophagy, anoikis and cell senescence, arresting cell cycle, regulating immune function, inhibiting metastasis and angiogenesis, reversing drug resistance and enhancing effects of chemotherapy. Along with the progress of research in this field, TCM will contribute more to the prevention and treatment of hepatocarcinoma.

Fucoidan inhibits the growth of hepatocellular carcinoma independent of angiogenesis

Some sulphated polysaccharides can bind bFGF but are unable to present bFGF to its high-affinity receptors. Fucoidan, a sulphated polysaccharide purified from brown algae, which has been used as an anticancer drug in traditional Chinese medicine for hundreds of years, exhibits a variety of anticancer effects, including the induction of the apoptosis and autophagy of cancer cells, the inhibition of the growth of cancer cells, the induction of angiogenesis, and the improvement of antitumour immunity. Our research shows that fucoidan dose not inhibit the expressions of VEGF, bFGF, IL-8, and heparanase in HCC cells and/or tumour tissues. Moreover, fucoidan exhibited low affinity for bFGF and could not block the binding of bFGF to heparan sulphated. Although fucoidan had no effect on angiogenesis and apoptosis in vivo, this drug significantly inhibited the tumour growth and the expression of PCNA. These results suggest that fucoidan exhibits an anticancer effect in vivo at least partly through inhibition of the proliferation of HCC cells, although it is unable to suppress the angiogenesis induced by HCC.

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

Anti-tumor activity of the proteins from Gecko (GP) on cervical cancer cells, and its signaling mechanisms were assessed by viable cell counting, propidium iodide (PI) staining, and Western blot analysis. GP induced the cell death of HeLa cells in a dose-dependent manner while it did not affect the viability of normal cells. Western blot analysis showed that GP decreased the activation of Akt, and co-administration of GP and Akt inhibitors synergistically exerted anti-tumor activities on HeLa cells, suggesting the involvement of PI3-kinase/Akt pathway in GP-induced cell death of the cancer cells. Indeed, the cytotoxic effect of GP against HeLa cells was inhibited by overexpression of constituvely active form of Akt in HeLa cells. The candidates of the functional proteins in GP were analyzed by Mass-spectrum. Taken together, our results suggest that GP elicits anti-tumor activity against HeLa cells by inhibition of PI3-kinase/Akt pathway.

Anticancer polysaccharides from natural resources: a review of recent research

Taking into account the rising trend of the incidence of cancers of various organs, effective therapies are urgently needed to control human malignancies. However, almost all of the chemotherapy drugs currently on the market cause serious side effects. Fortunately, several previous studies have shown that some non-toxic biological macromolecules, including polysaccharides and polysaccharide-protein complexes, possess anti-cancer activities or can increase the efficacy of conventional chemotherapy drugs. Based on these encouraging observations, a great deal of effort has been focused on discovering anti-cancer polysaccharides and complexes for the development of effective therapeutics for various human cancers. This review focuses on the advancements in the anti-cancer efficacy of various natural polysaccharides and polysaccharide complexes in the past 5 years. Most polysaccharides were tested using model systems, while several involved clinical trials.

Developing Phytocompounds from Medicinal Plants as Immunomodulators

Imbalance or malfunction of the immune systems is associated with a range of chronic diseases including autoimmune diseases, allergies, cancers and others. Various innate and adaptive immune cells that are integrated in this complex networking system may represent promising targets for developing immunotherapeutics for treating specific immune diseases. A spectrum of phytochemicals have been isolated, characterized and modified for development and use as prevention or treatment of human diseases. Many cytotoxic drugs and antibiotics have been developed from phytocompounds, but the application of traditional or new medicinal plants for use as immunomodulators in treating immune diseases is still relatively limited. In this review, a selected group of medicinal herbs, their derived crude or fractionated phytoextracts and the specific phytochemicals/phytocompounds isolated from them, as well as categorized phytocompound groups with specific chemical structures are discussed in terms of their immunomodulatory bioactivities. We also assess their potential for future development as immunomodulatory or inflammation-regulatory therapeutics or agents. New experimental approaches for evaluating the immunomodulatory activities of candidate phytomedicines are also discussed.