Rhus verniciflua stokes against advanced cancer: a perspective from the Korean Integrative Cancer Center.

Active anticancer molecules have been searched from natural products; many drugs were developed from either natural products or their derivatives following the conventional pharmaceutical paradigm of drug discovery. However, the advances in the knowledge of cancer biology have led to personalized medicine using molecular-targeted agents which create new paradigm. Clinical benefit is dependent on individual biomarker and overall survival is prolonged through cytostatic rather than cytotoxic effects to cancer cell. Therefore, a different approach is needed from the single lead compound screening model based on cytotoxicity. In our experience, the Rhus verniciflua stoke (RVS) extract traditionally used for cancer treatment is beneficial to some advanced cancer patients though it is herbal extract not single compound, and low cytotoxic in vitro. The standardized RVS extract's action mechanisms as well as clinical outcomes are reviewed here. We hope that these preliminary results would stimulate different investigation in natural products from conventional chemicals.

Efficacy and safety of standardized allergen-removed Rhus verniciflua Stokes extract in patients with advanced or metastatic pancreatic cancer: a Korean single-center experience.

BACKGROUND: Pancreatic cancer has the worst prognosis because of poor response to conventional therapy. We investigated the clinical feasibility of the standardized allergen-removed Rhus verniciflua Stokes (aRVS) extract as a potential therapeutic agent for advanced or metastatic pancreatic cancer. PATIENTS AND METHODS: From July 2006 to June 2010, patients with advanced or metastatic pancreatic adenocarcinoma were checked in our institution. After applying inclusion/exclusion criteria, 42 patients were eligible for the final analysis. Overall survival, clinical benefit and adverse events of these patients treated with aRVS in the aftercare period were determined. RESULTS: In May 2011, 39 patients had died and the remaining 3 patients were alive with evidence of disease. The mean RVS administration period was 3.86 months (95% confidence interval 2.52-5.20). The median overall survival for the entire population was 7.87 months (95% confidence interval 5.14-10.59), and the 1-year survival rate was 26.2%, which is compatible with external controls. Using univariate and multivariate analyses, aRVS treatment including performance status and prognostic index significantly affected overall survival. A clinical benefit response was also shown by aRVS treatment which was not dependent on concurrent chemotherapy. Adverse reactions to aRVS treatment were mostly mild and self-limiting. CONCLUSIONS: The standardized aRVS extract might be beneficial for patients with advanced or metastatic pancreatic cancer since it positively affected overall survival and clinical symptoms without significant adverse effects.

Fustin flavonoid attenuates beta-amyloid (1-42)-induced learning impairment.

Natural flavonoids ameliorate amyloid-beta peptide (Abeta)-induced neurotoxicity. We examined whether the fustin flavonoid affects Abeta-induced learning impairment in mice. Repeated treatment with fustin significantly attenuated Abeta (1-42)-induced conditioned fear and passive avoidance behaviors. This effect was comparable to that of EGb761, a standard extract of ginkgo. Fustin treatment significantly prevented decreases in acetylcholine (ACh) levels, choline acetyltransferase (ChAT) activity, and ChAT gene expression induced by Abeta (1-42). Fustin also consistently suppressed increases in acetyl cholinesterase (AChE) activity and AChE gene expression induced by Abeta (1-42). In addition, fustin significantly attenuated Abeta (1-42)-induced selective decreases in muscarinic M1 receptor gene expression and muscarinic M1 receptor binding activity (as determined by [(3)H]pirenzepine binding) by modulating extracellular signal-regulated kinase 1/2 (ERK 1/2) and cAMP response-element binding protein (CREB) phosphorylation and brain-derived neurotrophic factor (BDNF) expression. These effects of fustin were reversed by treatment with dicyclomine, a muscarinic M1 receptor antagonist, and SL327, a selective ERK inhibitor, but not by chelerythrine, a pan-protein kinase C (PKC) inhibitor. Taken together, our results suggest that fustin attenuates Abeta (1-42)-impaired learning, and that the ERK/CREB/BDNF pathway is important for the M1 receptor-mediated cognition-enhancing effects of fustin.

Impact of standardized Rhus verniciflua stokes extract as complementary therapy on metastatic colorectal cancer: a Korean single-center experience.

BACKGROUND: To investigate the clinical feasibility of the standardized Rhus verniciflua Stokes (RVS) extract for the metastatic colorectal cancer (mCRC), experimentally proven to have anticancer activities. PATIENTS AND METHODS: From July 2006 to November 2007, patients with conventional chemotherapy refractory mCRC were checked. After fulfilling inclusion/exclusion criteria, 36 patients were eligible for the final analysis. Overall survival and adverse events of patients treated with RVS in the aftercare period were determined. RESULTS: On October 21, 2008, a total of 26 patients died while the remaining 10 patients were alive with evidence of disease. The median RVS administration period was 2.7 months (95% confidence interval, 1.9-3.5). The median overall survival for the entire population was 10.9 months (95% confidence interval, 5.6-16.1) and 1-year survival rate was 44.4%, which is compatible with external controls. By survival analysis using Cox proportional hazards model, the performance status and the prior chemotherapy regimen number significantly affected overall survival. Adverse reactions to the RVS treatment were mostly mild and self-limiting. CONCLUSION: Complementary treatment with the standardized RVS extract might be beneficial for patients with mCRC, since it positively affected overall survival without significant side effects. This study suggests that RVS could be a natural anticancer agent candidate for the treatment of colorectal adenocarcinoma.

Quinoline derivative KB3-1 potentiates paclitaxel induced cytotoxicity and cycle arrest via multidrug resistance reversal in MES-SA/DX5 cancer cells.

AIMS: The resistance to chemotherapeutic drugs is a major problem for successful cancer treatment. Multidrug resistance (MDR) phenotype is characterized by over-expression of P-glycoprotein (P-gp) on the cancer cell plasma membrane that extrudes drugs out of the cells. Therefore, novel MDR reversal agents are desirable for combination therapy to reduce MDR and enhance anti-tumor activity. Thus, the present study was aimed to evaluate the potent efficacy of novel quinoline derivative KB3-1 as a potent MDR-reversing agent for combined therapy with TAX. MAIN METHODS: MDR reversing effect and TAX combined therapy were examined by Rhodamine accumulation and efflux assay and Confocal immunofluorescence microscopy, Western blotting, TUNEL assay, and cell cycle analysis. KEY FINDINGS: The discovery of quinoline-3-carboxylic acid [4-(2-[benzyl-3[-(3,4-dimethoxy-phenyl)-propionyl]-amino]-ethyl)-phenyl]-amide (KB3-1) as a novel MDR-reversal agent. KB3-1 significantly enhanced the accumulation and retention of a P-gp substrate, rhodamine-123 in the P-gp-expressing MES-SA/DX5 uterine sarcoma cells but not in the P-gp-negative MES-SA cells at non-toxic concentrations of 1 microM and 3 microM. Similarly, fluorescence microscopy observation revealed that KB3-1 reduced the effluxed rhodamine-123 expression on the membrane of MES-SA/DX5 cells. Consistent with decreased P-gp pumping activity, confocal microscopic observation revealed that KB3-1 effectively diminished the expression of P-gp in paclitaxel (TAX)-treated MES-SA/DX-5 cells. Furthermore, Western blotting confirmed that KB3-1 reduced P-gp expression and enhanced cytochrome C release and Bax expression in TAX treated MES-SA/DX-5 cells. In addition, KB3-1 enhanced TAX-induced apoptotic bodies in MES-SA/DX5 cells by TdT-mediated-dUTP nick-end labeling (TUNEL) staining assay aswell as potentiated TAX- induced cytotoxicity, G2/M phase arrest and sub-G1 apoptosis in MES-SA/DX5 cells but not in MES-SA cells. Interestingly, KB3-1 at 3 microM had comparable MDR-reversal activity to 10 microM verapamil, a well-known MDR- reversal agent. SIGNIFICANCE: KB3-1 can be a MDR-reversal drug candidate for combination chemotherapy with TAX.

Purification and biocompatibility of fermented hyaluronic acid for its applications to biomaterials.

BACKGROUND: Hyaluronic acid (HA) is of importance due to its diverse applications in pharmaceuticals and medical devices such as dermal filler, adhesion barriers, carrier for cells and bioactive molecules as well as scaffold biomaterials for tissue engineering. Evaluations of purification and biocompatibility of HA are required for its applications to biomaterials. RESULTS: After synthesizing HA by fermentation of streptococcus zooepidemicus for 25 hr, extensively purification of the fermented broth was performed to remove impurities using a filtration process for insoluble components and cells, and diverse adsorbents for soluble impurities. Its in vitro biocompatibility has been evaluated by measurement of cell counting and assay of cell live and dead. 60% yield of white HA powder was obtained, having 15-17 dL/g intrinsic viscosity with a molecular weight of approximately 1,000 kDa. While low molecular weight impurities and insoluble impurities were successfully removed using a ultrafiltration membrane with 50 KDa molecular weight cut, endotoxins, high molecular weight proteins and nucleic acids were removed from the broth by employing adsorbents such as alumina and activated carbons. Alumina showed the best results for the removal of endotoxins, all of the activated carbons were very effective in the removal of high molecular weight proteins and nucleic acids. The purified HA solution showed excellent cell compatibility with no cell damages as observed by both measurement of cell proliferation and observation of cell viability. CONCLUSIONS: We obtained high molecular weight HA with excellent biocompatibility as judged by both measurement of cell proliferation and viability, indicating high possibility of its applications to biomaterials.

Impact of Standardized Allergen-Removed Rhus verniciflua Stokes Extract on Advanced Adenocarcinoma of the Ampulla of Vater: A Case Series.

Background. Adenocarcinoma of the ampulla of Vater (AAV) is a rare malignancy that has a better prognosis than other periampullary cancers. However, the standard treatment for patients with relapsed or metastatic AAV has not been established. We investigated the clinical feasibility of standardized allergen-removed Rhus verniciflua stokes (aRVS) extract for advanced or metastatic AAV. Patients and Methods. From July 2006 to April 2011, we retrospectively reviewed all patients with advanced AAV treated with aRVS extract alone. After applying inclusion/exclusion criteria, 12 patients were eligible for the final analysis. We assessed the progression-free survival (PFS) and overall survival (OS) of these patients during the follow-up period. Results. The median aRVS administration period was 147.0 days (range: 72-601 days). The best tumor responses according to Response Evaluation Criteria in Solid Tumors were as follows: two with complete response, two with stable disease, and eight with progressive disease. The median OS was 15.1 months (range: 4.9-25.1 months), and the median PFS was 3.0 months (range: 1.6-11.4 months). Adverse reactions to the aRVS treatment were mostly mild and self-limiting. Conclusions. Prolonged survival was observed in patients with advanced AAV under the treatment of standardized aRVS extract without significant adverse effects.

The efficacy and safety of standardized allergen-removed Rhus verniciflua extract as maintenance therapy after first-line chemotherapy in patients with advanced non-small cell lung cancer.

Chemotherapy improves the survival of patients with advanced non-small cell lung cancer (NSCLC), but tumor progression is often inevitable. Strategies are needed to improve the therapeutic efficacy of chemotherapy. Over recent years, there has been increasing interest in the role of maintenance therapy after first-line chemotherapy. We investigated the efficacy and safety of standardized allergen-removed Rhus verniciflua Stokes extract (aRVS) as maintenance therapy in patients with non-progressive disease following first-line chemotherapy. We reviewed the medical records of 33 patients with advanced NSCLC, who started treatment with aRVS in a state of tumor regression or stable disease after completion of four or six cycles of induction chemotherapy at the Integrative Cancer Center, Kyung Hee University Hospital at Gangdong from June 2006 to April 2012. The primary objective of this study was progression-free survival (PFS) of aRVS as maintenance therapy. Secondary objectives included assessments of disease control rate (DCR), overall survival (OS), and the safety of aRVS treatment. The median PFS was 5.2 months with a 6- and 12-month PFS rate of 40.6% and 12.9%, respectively. The DCR was 93.9% and the median OS was 34.8 months. The overall survival rates at 12, 24, and 36 months were 84.2%, 76.7% and 49.9%, respectively. We observed no hematologic toxicity, nephrotoxicity, or hepatotoxicity during aRVS treatment. In conclusion, maintenance therapy with aRVS for patients with advanced NSCLC is well-tolerated and offers encouraging improved PFS and OS compared with historical controls. Our data provide further evidence that aRVS may be used beyond disease progression in this clinical setting.

Shrinkage of gastric cancer in an elderly patient who received Rhus verniciflua Stokes extract.

BACKGROUND: Many studies have suggested that the flavonoids from Rhus verniciflua Stokes (RVS) are anticancer agents, but a few clinical studies have reported on this topic. PATIENT AND METHOD: We present here the case of a female patient (82 years old) with an adenocarcinoma of the stomach that was first diagnosed via an abdomen computed tomography (CT) scan and endoscopic biopsy. Any conventional therapy such as surgical resection was not performed because of her advanced age. She wanted to receive alternative care, and so she was exclusively treated with standardized RVS extract. COURSE OF THERAPY AND RESULTS: Daily therapy with 900 mg of orally administered RVS extract was initiated on September 25, 2006. Five (5) months later, the gastroscopy and abdomen CT scan showed a marked decrease in the polypoid mass at the mid body and a slight decrease in the flat elevated lesion at the prepyloric antrum, as compared to tumor sizes on the first gastroscopy and abdomen CT scan. She is alive and doing well at the present time (April 2009). CONCLUSIONS: We suggest that RVS extract could be a candidate for a natural agent that induces selective apoptosis and inhibits cell growth in gastric adenocarcinoma.

Rhus verniciflua Stokes prevents cisplatin-induced cytotoxicity and reactive oxygen species production in MDCK-I renal cells and intact mice.

Cisplatin-induced oxidative stress can cause liver and kidney damage, thus limiting therapeutic efficacy. Thus, in the present study, since Rhus verniciflua Stokes (RVS) containing flavonoids has antioxidant effects, we investigated whether it can protect cisplatin-induced toxicity in vitro and in vivo, The in vitro effects of RVS on the cell viability and reactive oxygen species (ROS) production were investigated using cisplatin-treated Madin-Darby Canine kidney (MDCK)-I renal cells. Its in vivo effects were also studied in BALB/c mice inoculated with CT-26 colon adenocarcinoma cells and treated with cisplatin with or without RVS. Liver and renal functions were assessed together with indices of tissue oxidation. RVS prevented cisplatin-induced cytotoxicity and ROS release against MDCK-I cells. RVS alone exerted modest antitumor activity against CT-26 cells. When used concurrently with cisplatin, RVS prevented the increases in serum blood urea nitrogen (BUN), creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST), and NO, while reducing liver and kidney tissue MDA content, and increasing catalase, glutathione (GSH), and superoxide dismutase (SOD) activities. Moreover, the antitumor efficacy of cisplatin was not altered by concurrent administration of RVS. These findings demonstrate that RVS prevents cisplatin-induced toxicity in vitro and in vivo via an antioxidant activity without hurting its antitumor effectiveness, suggesting that RVS can be usefully applied to the neoplastic patients as a combined chemopreventive agent with cisplatin.