Dendritic cells might be one of key factors for eliciting antitumor effect by chemoimmunotherapy in vivo

Construction of an Innovative Nanogel and Its Applications for Achieving Chemo-Immunotherapy of Tumors

Malignant tumors, also known as cancers, are a global public health problem. Nanogels are promising carriers for the delivery of anticancer medicines. Therefore, based on the unique microenvironment of tumor cells and the advantages of nanogels, a simple and economical one-pot synthesis method was designed to construct natural polysaccharide-based redox-responsive nanogels (LDD NGs). The enhanced permeability and retention (EPR) effect enriched LDD NGs in tumor cells, which then rapidly collapsed and released the natural antitumor drug diosgenin (DG) and the natural polysaccharide lentinan (LNT) via the depletion of a high level of reduced glutathione (GSH) in tumor cells, resulting in a synergistic therapeutic effect of chemotherapy and immunotherapy. In vivo antitumor experiments showed that LDD NGs could inhibit the proliferation and metastasis of the A549 lung cancer cells. Further studies indicated that LDD NGs could increase the production of ROS and induce apoptosis of A549 cells. In addition, LNT released from LDD NGs could promote the proliferation of dendritic cells, increase the production of NO, and upregulate the expressions of the costimulatory molecules CD40, CD80, CD86, and MHC-II. The construction of LDD NGs was a novel drug synthesis approach that could provide fresh ideas for the development of polysaccharide-based redox-responsive drug delivery systems.

Nano-formulated delivery of active ingredients from traditional Chinese herbal medicines for cancer immunotherapy

Cancer immunotherapy has garnered promise in tumor progression, invasion, and metastasis through establishing durable and memorable immunological activity. However, low response rates, adverse side effects, and high costs compromise the additional benefits for patients treated with current chemical and biological agents. Chinese herbal medicines (CHMs) are a potential treasure trove of natural medicines and are gaining momentum in cancer immunomodulation with multi-component, multi-target, and multi-pathway characteristics. The active ingredient extracted from CHMs benefit generalized patients through modulating immune response mechanisms. Additionally, the introduction of nanotechnology has greatly improved the pharmacological qualities of active ingredients through increasing the hydrophilicity, stability, permeability, and targeting characteristics, further enhancing anti-cancer immunity. In this review, we summarize the mechanism of active ingredients for cancer immunomodulation, highlight nano-formulated deliveries of active ingredients for cancer immunotherapy, and provide insights into the future applications in the emerging field of nano-formulated active ingredients of CHMs.

Natural polysaccharides exert anti-tumor effects as dendritic cell immune enhancers

With the development of immunotherapy, the process of tumor treatment is also moving forward. Polysaccharides are biological response modifiers widely found in plants, animals, fungi, and algae and are mainly composed of monosaccharides covalently linked by glycosidic bonds. For a long time, polysaccharides have been widely used clinically to enhance the body's immunity. However, their mechanisms of action in tumor immunotherapy have not been thoroughly explored. Dendritic cells (DCs) are a heterogeneous population of antigen presenting cells (APCs) that play a crucial role in the regulation and maintenance of the immune response. There is growing evidence that polysaccharides can enhance the essential functions of DCs to intervene the immune response. This paper describes the research progress on the anti-tumor immune effects of natural polysaccharides on DCs. These studies show that polysaccharides can act on pattern recognition receptors (PRRs) on the surface of DCs and activate phosphatidylinositol 3-kinase (PI3K)/protein kinase B (AKT), mitogen-activated protein kinase (MAPK), nuclear factor-κB (NF-κB), Dectin-1/Syk, and other signalling pathways, thereby promoting the main functions of DCs such as maturation, metabolism, antigen uptake and presentation, and activation of T cells, and then play an anti-tumor role. In addition, the application of polysaccharides as adjuvants for DC vaccines, in combination with adoptive immunotherapy and immune checkpoint inhibitors (ICIs), as well as their co-assembly with nanoparticles (NPs) into nano drug delivery systems is also introduced. These results reveal the biological effects of polysaccharides, provide a new perspective for the anti-tumor immunopharmacological research of natural polysaccharides, and provide helpful information for guiding polysaccharides as complementary medicines in cancer immunotherapy.

Natural Polysaccharides and Their Derivates: A Promising Natural Adjuvant for Tumor Immunotherapy

The treatment process of tumor is advanced with the development of immunotherapy. In clinical experience, immunotherapy has achieved very significant results. However, the application of immunotherapy is limited by a variety of immune microenvironment. For a long time in the past, polysaccharides such as lentinan and Ganoderma lucidum glycopeptide have been used in clinic as adjuvant drugs to widely improve the immunity of the body. However, their mechanism in tumor immunotherapy has not been deeply discussed. Studies have shown that natural polysaccharides can stimulate innate immunity by activating upstream immune cells so as to regulate adaptive immune pathways such as T cells and improve the effect of immunotherapy, suggesting that polysaccharides also have a promising future in cancer therapy. This review systematically discusses that polysaccharides can directly or indirectly activate macrophages, dendritic cells, natural killer cells etc., binding to their surface receptors, inducing PI3K/Akt, mitogen-activated protein kinase, Notch and other pathways, promote their proliferation and differentiation, increasing the secretion of cytokines, and improve the state of immune suppression. These results provide relevant basis for guiding polysaccharide to be used as adjuvants of cancer immunotherapy.

Structurally characterized gallium-chrysin complexes with anticancer potential

Chemotherapeutic metal-based compounds are effective anticancer agents; however, their cytotoxic profile and significant side effects limit their wide application. Natural products, especially flavonoids, are a prominent alternative source of anticancer agents that can be used as ligands for the generation of new bioactive complexes with metal ions of known biochemical and pharmacological activities. Herein, we present the synthesis and detailed structural and physicochemical characterizations of three novel complex assemblies of Ga(iii) with the flavonoid chrysin and the ancillary aromatic chelators 1,10-phenanthroline, 2,2'-bipyridine and imidazole. The complexes constitute the only crystallographically characterized structures having a metal core from the boron group elements and a flavonoid as the ligand. The in vitro biological evaluation of the three complexes in a series of cancer cell lines of different origin established their cytotoxicity and ROS generating potential. In particular, the Ga(iii)-chrysin-imidazole complex displayed the highest anticancer efficacy against all cancer cell lines with IC50 values in the low micromolar range (<1.18 μM), a result worth further investigation.

Chemoimmunotherapeutic effect of combined treatment with ex vivo generated antigen-presenting immune cells and conventional antitumor agents in a mouse neuroblastoma model

PURPOSE

Combining antitumor immunotherapy with conventional intensive multimodal therapy may be considered for advanced neuroblastoma. We investigated combination therapy with ex vivo generated immunostimulatory cells and intraperitoneal doxorubicin.

METHODS

Immunogenic death of neuro-2a neuroblastoma cells was induced by doxorubicin or cisplatin (negative control). Mouse bone marrow cells were cultured with granulocyte-macrophage colony-stimulating factor, followed by addition of doxorubicin-killed neuro-2a cells with or without interleukin-4 and/or CpG-oligodeoxynucleotide to induce immunostimulatory cells. CD8α⁺ lymphocytes were cocultured with killed neuro-2a cells and immunostimulatory cells, and interferon-γ was measured in the supernatant. Furthermore, female A/J mice were injected with viable neuro-2a cells, followed by immunostimulatory cells and doxorubicin. Then intraabdominal tumor nodules were evaluated.

RESULTS

Bone marrow-derived immunostimulatory cells only promoted interferon-γ production by CD8α⁺ lymphocytes after first being stimulated by doxorubicin-killed neuro-2a cells and interleukin-4, followed by CpG-oligodeoxynucleotide. These cells had a surface antigen expression profile compatible with activated dendritic cells and suppressed tumors in mice intravenously injected with neuro-2a cells. Despite a similar surface antigen profile, the in vivo antitumor effect was stronger after injection of immunostimulatory cells induced by doxorubicin-killed neuro-2a cells compared with cells induced by cisplatin-killed neuro-2a cells. Moreover, interferon-γ production was greater when CD8α⁺ lymphocytes were cocultured with doxorubicin-killed neuro-2a cells and immunostimulatory cells rather than with cisplatin-killed cells.

CONCLUSION

Cells with antitumor activity can be induced from bone marrow cells. Combining such cells with doxorubicin may activate antitumor immunity in tumor-bearing mice. Interactions between induced immunostimulatory cells and conventional chemotherapy might be important for antitumor immunity.

Artesunate Activates the Intrinsic Apoptosis of HCT116 Cells through the Suppression of Fatty Acid Synthesis and the NF-κB Pathway

The artemisinin compounds, which are well-known for their potent therapeutic antimalarial activity, possess in vivo and in vitro antitumor effects. Although the anticancer effect of artemisinin compounds has been extensively reported, the precise mechanisms underlying its cytotoxicity remain under intensive study. In the present study, a high-throughput quantitative proteomics approach was applied to identify differentially expressed proteins of HCT116 colorectal cancer cell line with artesunate (ART) treatment. Through Ingenuity Pathway Analysis, we discovered that the top-ranked ART-regulated biological pathways are abrogation of fatty acid biosynthetic pathway and mitochondrial dysfunction. Subsequent assays showed that ART inhibits HCT116 cell proliferation through suppressing the fatty acid biosynthetic pathway and activating the mitochondrial apoptosis pathway. In addition, ART also regulates several proteins that are involved in NF-κB pathway, and our subsequent assays showed that ART suppresses the NF-κB pathway. These proteomic findings will contribute to improving our understanding of the underlying molecular mechanisms of ART for its therapeutic cytotoxic effect towards cancer cells.

Lentinan diminishes apoptotic bodies in the ileal crypts associated with S-1 administration

S-1 is an oral agent containing tegafur (a prodrug of 5-fluorouracil) that is used to treat various cancers, but adverse effects are frequent. Two pilot clinical studies have suggested that lentinan (LNT; β-1,3-glucan) may reduce the incidence of adverse effects caused by S-1 therapy. In this study, we established a murine model for assessment of gastrointestinal toxicity associated with S-1 and studied the effect of LNT. S-1 was administered orally to BALB/c mice at the effective dose (8.3mg/kg, as tegafur equivalent) once daily (5days per week) for 3weeks. Stool consistency and intestinal specimens were examined. We investigated the effect of combined intravenous administration of LNT at 0.1mg, which is an effective dose in murine tumor models. We also investigated the effect of a single administration of S-1. During long-term administration of S-1, some mice had loose stools and an increase in apoptotic bodies was observed in the ileal crypts. An increase in apoptotic bodies was also noted after a single administration of S-1 (15mg/kg). Prior or concomitant administration of LNT inhibited the increase in apoptotic bodies in both settings. Administration of LNT also increased the accumulation of CD11b⁺TIM-4⁺ cells in the ileum, while depletion of these cells by liposomal clodronate diminished the inhibitory effect of LNT on S-1 toxicity. Combined administration of LNT with S-1 led to a decrease in apoptotic bodies in the ileal crypts, possibly because LNT promoted phagocytosis of damaged cells by CD11b⁺TIM-4⁺ cells.

Aloe arborescens Polysaccharides: In Vitro Immunomodulation and Potential Cytotoxic Activity

Different polysaccharides were isolated from the leaves of Aloe arborescens using the gradient power of hydrogen followed by antitumor and immunomodulatory assay. The total polysaccharide content of different fractions, water-soluble polysaccharide (WAP), acid-soluble polysaccharide (ACP), and alkaline-soluble polysaccharide (ALP), was estimated using a phenol-sulfuric acid spectrophotometric method. WAP possessed a higher content of mannose and glucose than either ACP or ALP. In vitro antitumor activity was investigated in three different cancer cell lines, and in vitro immunomodulatory potential was assessed through phagocytosis and lymphocyte transformation assay. The results showed that WAP and ALP exhibited the most significant cytotoxicity against HepG2 human liver cancer cells, with IC₅₀ values of 26.14 and 21.46 μg/mL, respectively. In contrast, ALP was able to enhance lymphocyte transformation, whereas WAP had the most potent phagocytic activity. Molecular weight, total sugar and uronic acid content, Fourier transform-infrared analysis, and linkage type of bioactive polysaccharides were investigated. These findings revealed that the potential antitumor activity of the natural agents WAP and ALP was through an immunomodulation mechanism, which verifies the use of the plant as adjuvant supplement for cancer patients suffering immunosuppression during chemotherapy.

Advances in antitumor polysaccharides from phellinus sensu lato: Production, isolation, structure, antitumor activity, and mechanisms

Edible and medicinal fungi (mushrooms) are widely applied to functional foods and nutraceutical products because of their proven nutritive and medicinal properties. Phellinus sensu lato is a well-known medicinal mushroom that has long been used in preventing ailments, including gastroenteric dysfunction, diarrhea, hemorrhage, and cancers, in oriental countries, particularly in China, Japan, and Korea. Polysaccharides represent a major class of bioactive molecules in Phellinus s. l., which have notable antitumor, immunomodulatory, and medicinal properties. Polysaccharides that were isolated from fruiting bodies, cultured mycelia, and filtrates of Phellinus s. l. have not only activated different immune responses of the host organism but have also directly suppressed tumor growth and metastasis. Studies suggest that polysaccharides from Phellinus s. l. are promising alternative anticancer agents or synergizers for existing antitumor drugs. This review summarizes the recent development of polysaccharides from Phellinus s. l., including polysaccharide production, extraction and isolation methods, chemical structure, antitumor activities, and mechanisms of action.

The Effects of Active Hexose Correlated Compound (AHCC) on Levels of CD4+ and CD8+ in Patients with Epithelial Ovarian Cancer or Peritoneal Cancer Receiving Platinum Based Chemotherapy

Background:

Adjuvant chemotherapy is a required treatment for most patients with epithelial ovarian cancer (EOC) or peritoneal cancer. However, it has many adverse events which may affect oncologic outcomes. Active hexose correlated compound (AHCC) has been reported to be an immunoenhancer to decrease adverse events of chemotherapy.

Materials and Methods:

Patients were randomized and allocated to receive either AHCC three grams/day (500mg/capsule) or placebo. These drugs were administrated as two capsules orally three times a day throughout six cycles of chemotherapy. The primary outcome was a change of CD4+ and CD8+ T cell lymphocytes in peripheral blood samples from baseline to completion of chemotherapy. Secondary outcomes were rate of bone marrow suppression, adverse events and quality of life (QOL) as assessed by Thai version of the Functional Assessment of Cancer Therapy-General (FACT-G).

Results:

Study outcomes were analyzed in 28 patients, 14 patients in each group. Changes in CD4+ and CD8+ T cell lymphocytes levels were not significantly different between AHCC and placebo group; 43.5/ul (-237.5, 143.3) versus -69.5 /ul (-223.8, 165) for CD4+ level, p=0.61 and 49.5.0 /ul (-80, 153.3) versus 4.0 /ul (-173, 62.5) for CD8+ level, p=0.19. However, CD8+ levels were significantly higher in the AHCC group at the sixth cycle of chemotherapy; 392.5.0 /ul (310.8, 598) versus 259.5 /ul (170.5, 462.3), p=0.03. There was no difference in bone marrow suppression and QOL between the two groups. Adverse events in terms of nausea and vomiting significantly decreased but muscle pain significantly increased in the AHCC group.

Conclusions:

Changes in CD4+ and CD8+ T cell lymphocytes from baseline were not significantly increased in AHCC group. However, CD8+T cell lymphocytes levels were significantly higher in the AHCC group at the sixth cycle of chemotherapy.

Anticancer Properties of Chrysin on Colon Cancer Cells, In vitro and In vivo with Modulation of Caspase-3, -9, Bax and Sall4

BACKGROUND

The SALL4/Sall4 is constitutively expressed in human and mice. SALL4 mRNA could be used as a marker for the diagnosis of different types of cancers. On the other hand, chrysin has diverse biological properties.

OBJECTIVES

In the present study, the effect of the chrysin was investigated on the CT26 colon cancer in vitro and in vivo. Furthermore, the expression levels of the stem cell markers; sall4 and Bax was analyzed, as well.

MATERIALS AND METHODS

The cytotoxic effects and the type of cell death induced by chrysin were evaluated using a number of biological assays. The apoptotic pathway was examined by caspase-3and caspase-9 assay. The in vivo antitumor efficacy of chrysin on transplanted CT26 tumor cells in BALB/c mice was investigated. In addition, mRNA expression of sall4, Bax was analyzed with RT-PCR.

RESULTS

MTT assay and morphological characteristics showed that chrysin exerted a cytotoxic effect on CT26 cells in a dose dependent manner with IC₅₀= 80 μg.mL^-1. The biological assays have indicated that chrysin administrated cytotoxicity on colon cancer cells through recruitment of the apoptosis. Caspase-3 and caspase-9 colorimetric assays, in addition to Bax expression analysis, have indicated the involvement of intrinsic apoptotic pathway in the cytotoxic effect of the chrysin. The in vivo assay revealed a remarkable reduction of the colon tumor volume in treated mice (8, 10 mg.kg ^-1) as compared to the untreated mice. RT-PCR elucidated that chrysin attenuated tumor volume through down regulation of the sall4 and up-regulation of the Bax.

CONCLUSIONS

It was demonstrated that chrysin accomplishes anti-cancer effect on colon cancer cells via induction of the apoptosis and attenuation of the sall4 the expression. These findings introduce chrysin as an efficient apoptosis based therapeutic agent against colon cancer.

Chemo-Immunotherapy Using Lentinan for the Treatment of Gastric Cancer with Liver Metastases

Gastric cancer is the third leading cause of cancer-related mortality worldwide. Systemic chemotherapy is the main treatment option for advanced gastric cancer when the tumor is inoperable. Despite recent advances in chemotherapeutic agents, the prognosis of unresectable or recurrent gastric cancer remains extremely poor. In Japan, combination therapy including S-1 and cisplatin is the standard first-line treatment for advanced gastric cancer; however, the five-year survival rate remains very low. Lentinan, the backbone of beta-(1,3)-glucan with beta-(1,6) branches, an active ingredient purified from Shiitake mushrooms, has been approved as a biological response modifier for the treatment of gastric cancer. This agent has been used in combination with oral fluoropyrimidines to improve the overall survival of gastric cancer patients. A retrospective chart review on 138 metastatic gastric cancer patients receiving chemotherapy was performed in Nagoya Memorial Hospital from 1 September 2010 to 31 August 2015. 12 patients with liver metastases were treated by lentinan in combination with S-1-based chemotherapy. The rate of objective response was 42% (5/12) and the disease control rate was 83% (10/12) in response to chemo-immunotherapy using lentinan, with a median overall survival of 407 days (95% CI: 207-700 days).

Curcumin combined with oxaliplatin effectively suppress colorectal carcinoma in vivo through inducing apoptosis

Studies have shown chemopreventive and/or chemotherapeutic effects of several curcumin-based combinatorial treatments on colorectal cancer cells. However, their in vivo effects remain unclear. This study has demonstrated the therapeutic effect of curcumin and oxaliplatin, alone or in combination, on subcutaneously xenografted LoVo human colorectal cancer cells in immunodeficient (nu/nu) mice in vivo. Combinatorial administration of curcumin and oxaliplatin evidently inhibited the growth of colorectal cancer in nude mice, which was significantly more effective than either agent alone. Curcumin combined with oxaliplatin treatment induced apoptosis, accompanied by ultrastructural changes and cell cycle arrest in S and G2/M phases. Further mechanism analysis indicated that while the number of apoptotic tumor cells and the expression of Bax, caspase-3, and poly (ADP-ribose) polymerase (PARP) increased significantly, the expression of Bcl-2, survivin, HSP70, pro-caspase-3, and pro-PARP were dramatically suppressed in tumor cells after the treatment with combinatorial curcumin and oxaliplatin for 22 days. Taken together, the present study has demonstrated that administration of combined curcumin and oxaliplatin effectively suppressed colorectal carcinoma in vivo through inducing apoptosis and thus may provide an effective treatment for colorectal carcinoma.

The use of lentinan for treating gastric cancer

Natural compounds containing fungal β-glucans have been used to improve general health for thousands of years in China and Japan. Lentinan, the backbone of β-(1, 3)-glucan with β-(1, 6) branches, is one of the active ingredients purified from Shiitake mushrooms and has been approved as a biological response modifier for the treatment of gastric cancer in Japan. Despite recent advances in chemotherapeutic agents, unresectable or recurrent gastric cancer remains an incurable disease, with survival rates being far from satisfactory. Recent clinical studies have shown that chemo-immunotherapy using lentinan prolongs the survival of patients with advanced gastric cancer, as compared to chemotherapy alone. In addition, trastuzumab, an antibody against HER2/neu growth factor receptor, has been used for the treatment of gastric cancer in combination with cytotoxic chemotherapeutic agents. Lentinan may exert a synergistic action with anti-cancer monoclonal antibodies to activate complement systems through the mechanism of antibody-dependent cellular cytotoxicity and complement dependent cytotoxicity. Because a better understanding of its biological activities should enable us to use lentinan more efficiently in the treatment of gastric cancer, immunological effects provided by β-glucans, a possible mode of action of lentinan, and its clinical application including future potential uses are discussed in the present review.

Curcumin inhibits proliferation and induces apoptosis of human colorectal cancer cells by activating the mitochondria apoptotic pathway

Curcumin, a natural plant extract from Curcuma longa, is known for its anti-carcinogenic and chemopreventive effects on a variety of experimental cancer models. In this study, we evaluated the effects of curcumin and elucidated its mechanism in human colorectal carcinoma cells. Cell viability assay showed that curcumin significantly inhibited the growth of LoVo cells. Curcumin treatment induced the apoptosis accompanied by ultra-structural changes and release of lactate dehydrogenase in a dose-dependent manner. Moreover, treatment with 0-30 µg/mL curcumin decreased the mitochondrial membrane potential and activated the caspase-3 and caspase-9 in a dose- and time-dependent manner. Nuclear and annexin V/PI staining showed that curcumin induced the apoptosis of LoVo cells. FACS analysis revealed that curcumin could induce the cell cycle arrest of LoVo cells at the S phase. Furthermore, western blotting analysis indicated that curcumin induced the release of cytochrome c, a significant increase of Bax and p53 and a marked reduction of Bcl-2 and survivin in LoVo cells. Taken together, our results suggested that curcumin inhibited the growth of LoVo cells by inducing apoptosis through a mitochondria-mediated pathway.

Lentinan: hematopoietic, immunological, and efficacy studies in a syngeneic model of acute myeloid leukemia

Lentinan, a beta-glucan nutritional supplement isolated from the shitake mushroom (Lentula edodes), is a biological response modifier with immunostimulatory properties. Concomitantly, the role of beta-glucans as chemoimmunotherapeutic in a number of solid cancers has been widely documented. We investigated the effects of nutritional grade lentinan upon BN rats and in a preclinical syngeneic model of acute myeloid leukemia. BN rats supplemented daily with lentinan exhibited weight gains, increased white blood cells, monocytes, and circulating cytotoxic T-cells; and had a reduction in anti-inflammatory cytokines IL-4, IL-10, and additionally IL-6. Lentinan treatment of BN rats with BNML leukemia resulted in improved cage-side health and reduced cachexia in the terminal stage of this aggressive disease. Combination of lentinan with standards of care in acute myeloid leukemia, idarubicin, and cytarabine increased average survival compared with monotherapy and reduced cachexia. These results indicate that nutritional supplementation of cancer patients with lentinan should be further investigated.

Protective effects of fraction 1a of polysaccharides isolated from Solanum nigrum Linne on thymus in tumor-bearing mice

AIM OF THE STUDY

To further screen out the anti-tumor active compound of polysaccharides isolated from Solanum nigrum Linne (SNL-P), which had shown to have anti-cervical cancer and modulating properties, and evaluate the thymus protective effects of this active compound.

MATERIAL AND METHODS

SNL-P was separated and purified by column chromatography, and its anti-cervical cancer activity was evaluated by mice models injected of ascites U14 cells. Furthermore, the protective effect of fraction 1a of SNL-P (SNL-P1a) on the thymus tissue of tumor-bearing mice was evaluated by histological study and TUNEL staining. Finally, the protein expression of Bcl-2 and Bax gene were assayed by immunohistochemistry.

RESULTS

SNL-P1a has shown a marked inhibition effect on U14 cevical cancer, it restore the ratio of CD4(+)/CD8(+) peripheral blood T-lymphocyte subpopulation. Histological study and TUNEL staining results showed that SNL-P1a protect thymus tissue against the onslaught of tumor by inhibiting thymus lymphocyte apoptosis, and immunohistochemistry assay displayed that SNL-P1a treatment could increase Bcl-2/Bax ratio in thymus lymphocytes of tumor-bearer, which might promote more thymus lymphocytes towards proliferation.

CONCLUSION

SNL-P1a had significant growth inhibition effect on U14 cervical cancer and protective effect on thymus tissue of tumor-bearing mice.

Antitumor and immunomodulating effects of polysaccharides isolated from Solanum nigrum Linne

We have examined the effects of the crude polysaccharides isolated from Solanum nigrum Linne (SNL-P) in vitro and in vivo against U14 cervical cancer. SNL-P showed no antiproliferative effects in vitro at a dose up to 1 mg/ml. In vivo administration with SNL-P (90, 180, 360 mg/kg b.w., p.o.) decreased the number of ascites tumor cells and prolonged the survival time of U14 cervical-cancer-bearing mice. FACScan flow cytometer analysis showed that most of the ascites tumor cells were arrested in G2/M phase of cell cycle and the ratio of CD4+/CD8+ peripheral blood T-lymphocyte subpopulations were restored following treatment of SNL-P. Furthermore, the treatment with SNL-P also caused a significant increment in IFN-gamma (p < 0.01, 90, 180 and 360 mg/kg b.w.) and a remarkable decrease in Il-4 (p < 0.01, 90, 180 mg/kg b.w.; p < 0.05, 360 mg/kg b.w.) by the method of ELISA. These data showed that SNL-P possess potent antitumor activity and SNL-P might exert antitumor activity via activation of different immune responses in the host rather than by directly attacking cancer cells on the U14 cervical cancer bearing mice. Thus, SNL-P could be used as an immunomodulator and an anticancer agent.

Medicinal importance of fungal beta-(1-->3), (1-->6)-glucans

Non-cellulosic beta-glucans are now recognized as potent immunological activators, and some are used clinically in China and Japan. These beta-glucans consist of a backbone of glucose residues linked by beta-(1-->3)-glycosidic bonds, often with attached side-chain glucose residues joined by beta-(1-->6) linkages. The frequency of branching varies. The literature suggests beta-glucans are effective in treating diseases like cancer, a range of microbial infections, hypercholesterolaemia, and diabetes. Their mechanisms of action involve them being recognized as non-self molecules, so the immune system is stimulated by their presence. Several receptors have been identified, which include: dectin-1, located on macrophages, which mediates beta-glucan activation of phagocytosis and production of cytokines, a response co-ordinated by the toll-like receptor-2. Activated complement receptors on natural killer cells, neutrophils, and lymphocytes, may also be associated with tumour cytotoxicity. Two other receptors, scavenger and lactosylceramide, bind beta-glucans and mediate a series of signal pathways leading to immunological activation. Structurally different beta-glucans appear to have different affinities toward these receptors and thus generate markedly different host responses. However, the published data are not always easy to interpret as many of the earlier studies used crude beta-glucan preparations with, for the most part, unknown chemical structures. Careful choice of beta-glucan products is essential if their benefits are to be optimized, and a better understanding of how beta-glucans bind to receptors should enable more efficient use of their biological activities.

Toward a core nutraceutical program for cancer management

As previously suggested, it may be feasible to impede tumorevoked angiogenesis with a nutraceutical program composed of glycine, fish oil, epigallocatechin-3-gallate, selenium, and silymarin, complemented by a low-fat vegan diet, exercise training, and, if feasible, a salicylate and the drug tetrathiomolybdate. It is now proposed that the scope of this program be expanded to address additional common needs of cancer patients: blocking the process of metastasis; boosting the cytotoxic capacity of innate immune defenses (natural killer [NK] cells); preventing cachexia, thromboembolism, and tumor-induced osteolysis; and maintaining optimal micronutrient status. Modified citrus pectin, a galectin-3 antagonist, has impressive antimetastatic potential. Mushroombeta-glucans and probiotic lactobacilli can amplify NK activity via stimulatory effects on macrophages. Selenium, beta-carotene, and glutamine can also increase the number and/or cytotoxic activity of NK cells. Cachectic loss of muscle mass can be opposed by fish oil, glutamine, and beta-hydroxy-beta-methylbutyrate. Fish oil, policosanol, and vitamin D may have potential for control of osteolysis. High-dose aspirin or salicylates, by preventing NF-B activation, can be expected to aid prevention of metastasis and cachexia while down-regulating osteolysis, but their impacts on innate immune defenses will not be entirely favorable. A nutritional insurance formula crafted for the special needs of cancer patients can be included in this regimen. To minimize patient inconvenience, this complex core nutraceutical program could be configured as an oil product, a powder, and a capsule product, with the nutritional insurance formula provided in tablets. It would be of interest to test this program in nude mouse xenograft models.

Role of conventional treatments on circulating and monocyte-derived dendritic cells in colorectal cancer

We investigated the effects of metastasis, surgery and chemotherapy on both circulating dendritic cells (DCs) and monocyte-derived-DCs (MoDCs) in colorectal cancer (CRC) patients. Metastatic or nonmetastatic CRC patients had significantly reduced DC subsets compared to healthy subjects (p < 0.001). These cells were significantly higher in metastatic than in nonmetastatic patients. MoDCs were significantly lower in metastatic than healthy and nonmetastatic subjects (p < 0.001). Surgically treated patients had nearly one-half circulating DC subsets compared to healthy subjects (p < 0.001) while no difference was found between unoperated and healthy subjects. MoDCs obtained from tumor-bearing were significantly higher than in operated subjects. In both cases, MoDCs were significantly lower than in healthy subjects (p < 0.001). Circulating DCs and MoDCs were significantly lower in CRC patients, with or without chemotherapy, compared to healthy subjects (p < 0.001). Compared to untreated, chemotherapy-treated patients had 30% fewer DC subsets and lower MoDCs. Characterization of circulating DC subsets and MoDCs may elucidate CRC patients' immune system status.