Prospective trial of the herbal supplement PC-SPES in patients with progressive prostate cancer

Network pharmacology combined with molecular docking revealed the potential targets of Coridius chinensis in prostate cancer treatment

BACKGROUND

Prostate cancer (PCa) has high morbidity and mortality rates in elderly men. With a history of thousands of years, traditional Chinese medicine derived from insects could be an important source for developing cancer-targeted drugs to prevent tumorigenesis, enhance therapeutic effects, and reduce the risk of recurrence and metastasis. Multiple studies have shown that Coridius chinensis (Cc) has anticancer effects.

AIM

To elucidate the mechanism of action of Cc against PCa via network pharmacology and molecular docking.

METHODS

Potential targets for Cc and PCa were predicted using ChemDraw 19.0 software, the PharmMapper database and the GeneCards database. Then, the STRING database was used to construct the protein–protein interaction network. Gene Ontology (GO), Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment and molecular docking analyses were subsequently conducted to identify the key targets, active ingredients and pathways involved.

RESULTS

GO and KEGG analyses indicated that the PI3K-Akt signalling pathway was the critical pathway (P value < 1.0 × 10^-8). Multiple targeting ingredients that can affect multiple pathways in PCa have been identified in Cc. Seven active compounds (asponguanosines A, asponguanine B, asponguanine C, aspongpyrazine A, N-acetyldopamine, aspongadenine B and aspongpyrazine B) were selected for molecular docking with 9 potential targets, and the results revealed that aspongpyrazine A and asponguanosine A are the main components by which Cc affects PCa (affinity<-5 kcal/mol, hydrogen bonding), but more studies are needed.

CONCLUSION

We used network pharmacology to predict the bioactive components and important targets of Cc for the treatment of PCa, supporting the development of Cc as a natural anticancer agent.

Are There Adverse Events after the Use of Sexual Enhancement Nutrition Supplements? A Nationwide Online Survey from Japan

Dozens of safety alerts for sexual enhancement and weight loss dietary supplements have been launched from the government not only in Japan but also overseas. However, adverse events have been reported only for the use of weight loss supplements, and the prevalence of use and adverse events in sexual enhancement supplements is not known in Japan. To address this issue, we assessed the situation of sexual enhancement supplement use through a nationwide online survey. The prevalence of sexual enhancement supplement use among males was 23.0%. Use of these supplements was higher among younger people than among older people (p < 0.001). In total, 17.6% of users had experienced adverse events, but 58.3% of them did not consult about the events with anybody because of the temporality of their symptoms and their sense of shame. In addition, eight supplement products were found to be possible adulterated supplements in this survey. It is necessary to inform the public about the risk of sexual enhancement supplement use and also prepare a place for consultation on media channels that younger people are more familiar with, in order to monitor adverse events while also preserving their privacy.

Effects of non-steroidal anti-inflammatory drug-activated gene-1 on Ganoderma lucidum polysaccharides-induced apoptosis of human prostate cancer PC-3 cells

Ganoderma lucidum polysaccharides (GLP) has been demonstrated to elicit antitumorigenic and proapoptotic activities in cancer; however, the molecular mechanisms underlying the anticancer effects of GLP have yet to be elucidated. Non-steroidal anti-inflammatory drug-activated gene-1 (NAG-1) has been reported to exert proapoptotic effects and therefore, may serve an important role in cancer prevention. The present study aimed to elucidate the molecular mechanism by which GLP stimulates anticancer activity in human prostate cancer (PCa) PC-3 cells. In addition, the role of NAG-1 in GLP-induced cancer inhibition was examined. The results of the present study demonstrated that GLP significantly inhibited cell viability in a time- and dose-dependent manner in PC-3 cells. Flow cytometry indicated that GLP induced late apoptosis, which was accompanied by poly (ADP-ribose) polymerase 1 (PARP) cleavage, and inhibition of pro-caspase-3, -6 and -9 protein expression. Furthermore, it was observed that the expression levels of NAG-1, and its transcriptional factor early growth response-1, were upregulated in a time- and dose-dependent manner upon GLP treatment. The results of a luciferase assay demonstrated that GLP induced the promoter activity of NAG-1, thus indicating that NAG-1 may be transcriptionally regulated by GLP. The secretion of NAG-1 proteins into the cell culture medium was also upregulated upon GLP treatment. Furthermore, inhibition of NAG-1 expression by small interfering RNA significantly, but not completely, prevented GLP-induced apoptosis, and reversed the effects of GLP on PARP and pro-caspase expression. It was further demonstrated that GLP inhibited the phosphorylation of protein kinase B and mitogen-activated protein kinase/extracellular signal-regulated kinase signaling in PC-3 cells. The present study is the first, to the best of our knowledge, to report that GLP may induce apoptosis of PCa cells, which is partially mediated through NAG-1 induction. The present findings may be helpful in elucidating the anticancer mechanisms of GLP through NAG-1 induction for its chemopreventive potential in PCa.

Scutellaria baicalensis and Cancer Treatment: Recent Progress and Perspectives in Biomedical and Clinical Studies

Scutellaria baicalensis (Huangqin in Chinese) is a major traditional Chinese medicine (TCM) herb, which has a long history of use in the treatment of a variety of symptoms correlated with cancer. In the past decade, the potential of S. baicalensis and single compounds derived from it as anticancer agents targeting various pathways has received extensive research attention. Specifically, the proliferation and metastases inhibiting properties of the single compounds in cancer have been studied; however, the underlying mechanisms remain unclear. This review summarizes the various mechanisms, pathways and molecular targets involved in the anticancer activity of S. baicalensis and its single compounds. However, the aim of this review is to provide a more thorough view of the last 10 years to link traditional use with modern research and to highlight recently discovered molecular mechanisms. Extracts and major flavonoids derived from S. baicalensis have been found to possess anticancer effects in multiple cancer cell lines both in vitro and in vivo. Further investigation is warranted to better understand the underlying mechanisms and to discover novel targets and cancer therapeutic drugs that may improve both the survival and quality of life of cancer patients.

Isoliquiritigenin exhibits anti-proliferative properties in the pituitary independent of estrogen receptor function

The plant flavonoid isoliquiritigenin (ISL) is a botanical estrogen widely taken as an herbal supplement to ease the symptoms of menopause. ISL has been also shown to have anti-tumor properties in a number of cancer cell backgrounds. However, the effects of ISL on normal cells are less well known and virtually unstudied in the context of the pituitary gland. We have established a pituitary explant culture model to screen chemical agents for gene expression changes within the pituitary gland during a period of active proliferation and differentiation. Using this whole-organ culture system we found ISL to be weakly estrogenic based on its ability to induce Cckar mRNA expression, an estrogen receptor (ER) mediated gene. Using a range of ISL from 200nM to 200μM, we discovered that ISL promoted cell proliferation at a low concentration, yet potently inhibited proliferation at the highest concentration. ICI 182,780 failed to antagonize ISL's repression of pituitary cell proliferation, indicating the effect is independent of ER signaling. Coincident with a decrease in proliferating cells, we observed down-regulation of transcript for cyclin D2 and E2 and a strong induction of mRNA and protein for the cyclin dependent kinase inhibitor Cdkn1a (p21). Importantly, high dose ISL did not alter the balance of progenitor vs. differentiated cell types within the pituitary explants and they seemed otherwise healthy; however, TUNEL staining revealed an increase in apoptotic cell death in ISL treated cultures. Our results merit further examination of ISL as an anti-tumor agent in the pituitary gland.

PC-SPES: A Brief Overview

PC-SPES is a botanically based dietary supplement that has been used by men following prostate cancer treatment to reduce prostate-specific antigen levels. It is a complex matrix comprising 8 herbs whose known chemistry and biology do not account for the observed clinical activity. Recent disclosures have forced the product to be withdrawn from the market. Aspects of previous scientific research on the product, including clinical information, are reviewed, and some suggestions are offered for the future scientific needs of this product. Some thoughts are also offered on what the recall of PC-SPES means for the future scientific directions of the dietary supplement industry.

Herbal Formulation C168 Attenuates Proliferation and Induces Apoptosis in HCT 116 Human Colorectal Carcinoma Cells: Role of Oxidative Stress and DNA Damage

The use of herbal formulations has gained scientific interest, particularly in cancer treatment. In this study, the herbal formulation of interest, denoted as C168, is a mixture of eight genera of plants. This study aims to investigate the antiproliferative effect of C168 methanol extract (CME) on various cancer cells and its underlying mechanism of action on the most responsive cell line, namely, HCT 116 cells. CME exerted antiproliferative activities on HCT 116 colorectal carcinoma cells and HepG2 hepatocellular carcinoma cells but not on CCD-841-CoN normal colon epithelial cells, Jurkat E6.1 lymphoblastic leukemic cells, and V79-4 Chinese hamster lung fibroblasts. Further investigation on HCT 116 cells showed that CME induced G₂/M cell-cycle arrest and apoptosis. Treatment of CME induced oxidative stress in HCT 116 cells by increasing the superoxide anion level and decreasing the intracellular glutathione. CME also increased tail moment value and H2AX phosphorylation in HCT 116 cells, suggesting DNA damage as an early signal of CME induced apoptosis. Loss of mitochondrial membrane potential in CME-treated cells also indicated the involvement of mitochondria in CME induced apoptosis. This study indicated the selectivity of CME toward colon cancer cells with the involvement of oxidative damage as its possible mechanism of action.

Effects of Flavonoids from Food and Dietary Supplements on Glial and Glioblastoma Multiforme Cells

Quercetin, catechins and proanthocyanidins are flavonoids that are prominently featured in foodstuffs and dietary supplements, and may possess anti-carcinogenic activity. Glioblastoma multiforme is the most dangerous form of glioma, a malignancy of the brain connective tissue. This review assesses molecular structures of these flavonoids, their importance as components of diet and dietary supplements, their bioavailability and ability to cross the blood-brain barrier, their reported beneficial health effects, and their effects on non-malignant glial as well as glioblastoma tumor cells. The reviewed flavonoids appear to protect glial cells via reduction of oxidative stress, while some also attenuate glutamate-induced excitotoxicity and reduce neuroinflammation. Most of the reviewed flavonoids inhibit proliferation of glioblastoma cells and induce their death. Moreover, some of them inhibit pro-oncogene signaling pathways and intensify the effect of conventional anti-cancer therapies. However, most of these anti-glioblastoma effects have only been observed in vitro or in animal models. Due to limited ability of the reviewed flavonoids to access the brain, their normal dietary intake is likely insufficient to produce significant anti-cancer effects in this organ, and supplementation is needed.

Ethanol extract of Remotiflori radix induces endoplasmic reticulum stress-mediated cell death through AMPK/mTOR signaling in human prostate cancer cells

Remotiflori radix is the root of Mosidae, which has long been used as a traditional medicine to treat chills, fever, and phlegm discharge. The ethanol extract of Mosidae leaves (MLE) possesses strong antioxidant and chemopreventive activities. However, the anti-cancer effects of the Remotiflori radix have not been examined. We used the ethanol extract of Remotiflori radix (ERR) and the PC-3 and DU145 prostate cancer cell lines in this study. We found that > 100 μg/mL ERR caused dose- and time-dependent cell death. Autophagic and apoptotic cell numbers increased in a dose-dependent manner as incubation time was prolonged, and LC3 punctuation, YO-PRO-1 uptake, DNA fragmentation, activation of caspases, and PARP cleavage were induced. Phosphorylation of AMPK, ULK, and p38 was increased after ERR treatment, and the level of the ER stress marker CHOP was also elevated. AMPK knockdown dramatically blocked ERR-mediated CHOP expression and cell death, suggesting that AMPK activation and ER stress play a critical role in ERR-induced cell death. Furthermore, oral administration of ERR at 50 mg/kg efficiently suppressed tumorigenic growth of PC-3 cells with no adverse effects. These results suggest that the ERR can be used as a safe and potent alternative therapy for patients with prostate cancer.

Safety surveillance of traditional Chinese medicine: current and future

Herbal medicine, including traditional Chinese medicine, has been used for the prevention, treatment, and cure of disorders or diseases for centuries. In addition to being used directly as therapeutic agents, medicinal plants are also important sources for pharmacological drug research and development. With the increasing consumption of herbal products intended to promote better health, it is extremely important to assure the safety and quality of herbal preparations. However, under current regulation surveillance, herbal preparations may not meet expectations in safety, quality, and efficacy. The challenge is how to assure the safety and quality of herbal products for consumers. It is the responsibility of producers to minimize hazardous contamination and additives during cultivation, harvesting, handling, processing, storage, and distribution. This article reviews the current safety obstacles that have been involved in traditional Chinese herbal medicine preparations with examples of popular herbs. Approaches to improve the safety of traditional Chinese medicine are proposed.

Application of transcriptomics in Chinese herbal medicine studies

Transcriptomics using DNA microarray has become a practical and popular tool for herbal medicine study because of high throughput, sensitivity, accuracy, specificity, and reproducibility. Therefore, this article focuses on the overview of DNA microarray technology and the application of DNA microarray in Chinese herbal medicine study. To understand the number and the objectives of articles utilizing DNA microarray for herbal medicine study, we surveyed 297 frequently used Chinese medicinal herbs listed in Pharmacopoeia Commission of People's Republic of China. We classified these medicinal herbs into 109 families and then applied PudMed search using “microarray” and individual herbal family as keywords. Although thousands of papers applying DNA microarray in Chinese herbal studies have been published since 1998, most of the articles focus on the elucidation of mechanisms of certain biological effects of herbs. Construction of the bioactivity database containing large-scaled gene expression profiles of quality control herbs can be applied in the future to analyze the biological events induced by herbs, predict the therapeutic potential of herbs, evaluate the safety of herbs, and identify the drug candidate of herbs. Moreover, the linkage of systems biology tools, such as functional genomics, transcriptomics, proteomics, metabolomics, pharmacogenomics and toxicogenomics, will become a new translational platform between Western medicine and Chinese herbal medicine.

Inhibitory Effects of PC-SPESII Herbal Extract on Human Breast Cancer Metastasis

Cancer metastasis is refractory to most forms of chemotherapy. Conventional and alternative drugs, such as Chinese herbal remedies, have been developed to target metastatic cancer cells. In this study, we investigated the effects of PC-SPESII, an herbal formulation, on the migration, invasion, and metastasis of an experimental human breast cancer cell line in vivo and in vitro. PC-SPESII suppressed pulmonary metastasis and tumor growth of MDA-MB-231 human breast cancer xenografts without affecting body weight, liver function, and kidney function. PC-SPESII also inhibited MDA-MB-231 cell migration and invasion in vitro in a dose-dependent manner. Based on ELISA analysis, secretion of MMP-2 and MMP-9, proteins associated with extracellular matrix degradation, was reduced in response to PC-SPESII treatment. Western blot analysis of whole-cell extracts revealed that the levels of proteolytic proteins associated with matrix and base membrane degradation (MMP-2, MMP-9, and uPA) were decreased and the levels of their endogenous inhibitors (TIMP1 and TIMP2) were increased. Moreover, the p38MAPK and SAPK/JNK signaling pathway, which stimulates proteolytic enzymes and matrix degradation, was inhibited by PC-PSESII. Remarkably, cotreatment with PC-PSESII and p38MAPK or SAPK/JNK inhibitors magnified the antimetastatic phenotype. Our results indicate that PC-PSESII impairs human breast cancer metastasis by regulating proteolytic enzymes and matrix dynamics through the p38MAPK and SAPK/JNK pathway.

How can I help myself? A critical review of modifiable behaviors, medications, and complementary alternative medicine for men receiving radiotherapy for prostate cancer

Men receiving radiation for prostate cancer frequently want to know what steps they can take to optimize their chance of cure and reduce their risk of side effects. A variety of modifiable behaviors, medications, and complementary alternative medicine interventions have been investigated in this regard. In this review, we summarize data on tobacco use, exercise, statins and aspirin, and vitamins. There is limited randomized data supporting any of the interventions and additional studies are needed before clinicians can confidently inform their patients regarding what steps to take to improve their outcomes.

Non-metastatic CRPC and asymptomatic metastatic CRPC: which treatment for which patient?

The introduction of early PSa-based diagnosis has profoundly impacted the epidemiology of castration-resistant prostate cancer (CRPC). Many patients enter the disease at an early stage when the only sign of resistance to androgen deprivation therapy (ADT) is a progressive elevation of prostate-specific antigen (PSA). This created a very heterogeneous population of non-metastatic (M0) CRPC. PSa kinetics is the most powerful indicator of aggressiveness in that population and can be used to trigger imaging investigation and enrollment in clinical trials. Several registered and near to come treatments have not been tested in that population but in men with more advanced metastatic and often symptomatic disease. Several agents have been investigated to delay the onset of the first bone metastasis but only one, denosumab, has reached its end-point. Because CRPC remains largely driven by the androgen receptor (AR), physicians have relied on second-line hormonal manipulations to delay the progression of the disease, including first generation antiandrogens, adrenal synthesis inhibitors, steroids and estrogens. The data however are mostly limited to phase II trials.

Cytotoxicity of herbal extracts used for treatment of prostatic disease on head and neck carcinoma cell lines and non-malignant primary mucosal cells

Previously, a growth inhibiting effect of PC-Spes on head and neck carcinoma cell lines had been demonstrated. In order to determine the toxic impact of particular herbs in the mixture, we exposed the head and neck cancer cell lines FADU, HLaC79 and its Paclitaxel-resistant subline HLaC79-Clone1 as well as primary mucosal keratinocytes to increasing concentrations of the herbal mixture Prostaprotect, which has a similar formulation as PC-Spes, as well as its single herbal components Dendranthema morifolium, Ganoderma lucidium, Glycyrrhiza glabra, Isatis indigotica, Panax pseudo-ginseng, Rabdosia rubescens, Scutellaria baicalensis and Pygeum africanum. Growth inhibition was measured using the MTT assay. Expression of P-glycoprotein (P-GP), multidrug resistance protein-1 (MRP-1), multidrug resistance protein-2 (MRP-2), breast cancer resistance protein (BCRP) and androgen receptor (AR) were examined by western blot analysis. Pygeum africanum extract clearly turned out as the main cytotoxic component of the Prostaprotect prescription mixture, and initated apoptosis in sensitive cell lines. All other extracts had only minor toxic effects. Western blot analysis revealed increased expression of P-GP in HLaC79-Clone1 cells, while HLaC79 and FADU cells were negative. All three cell lines were negative for MRP-1 and BCRP but positive for MRP-2. HLaC79 and its descendant HLaC79-Clone1 both expressed AR, as verified by western blotting and immunofluorescence staining. Primary mucosal keratinocytes were negative for all multidrug resistance markers as well as for AR. Growth inhibition rates of the single herbal extracts were compared with previously published results in prostate carcinoma cell lines. The relationship between expression levels of AR and multidrug resistance markers in relation to the measured toxicity of herbal extracts in our head and neck cancer cell system is critically discussed.

A phase I study of the chinese herbal medicine PHY906 as a modulator of irinotecan-based chemotherapy in patients with advanced colorectal cancer

PHY906 is a novel Chinese herbal preparation that has been used in the Orient for over 1800 years to treat a wide range of gastrointestinal side effects including diarrhea, abdominal cramps, vomiting, fever, and headache. Preclinical and clinical studies were conducted to further investigate the biologic and clinical activities of this herbal medicine. To ensure standardization and maintain interbatch reliability of PHY906, high performance liquid chromatography (HPLC) was used to establish a "chemical fingerprint" of PHY906. In vivo preclinical studies using the murine Colon 39 tumor model showed that PHY906 protected against the weight loss associated with irinotecan treatment. In the presence of PHY906, mice were able to tolerate otherwise lethal doses of irinotecan. Significantly improved antitumor activity and overall survival were observed in animals treated with the combination of irinotecan and PHY906 versus irinotecan alone. The combination of PHY906 with irinotecan, 5-fluorouracil (5-FU), and leucovorin (LV) also resulted in at least additive antitumor activity with no increased host toxicity. Based on these in vivo studies, a phase I multicenter, double-blind, randomized, placebo-controlled, dose escalation, cross-over study of PHY906 as a modulator of the weekly, bolus regimen of irinotecan, 5-FU, and LV (IFL) in the first-line treatment of patients with advanced colorectal cancer (CRC) was conducted. The specific objectives of this clinical trial were to determine the safety and tolerability of PHY906 when administered concomitantly with the bolus, weekly IFL regimen. Treatment with PHY906 did not alter the pharmacokinetics of 5-FU, irinotecan, or the irinotecan metabolite SN-38.

The mechanism of action of estrogen in castration-resistant prostate cancer: clues from hormone levels

BACKGROUND

Estrogen therapy plays a role in the management of castration-resistant prostate cancer (CRPC), although the mechanism of action is not fully known. This current analysis reports the relationship of change in adrenal androgen levels and prostate-specific antigen (PSA) response in patients with CRPC treated with estrogen therapy.

PATIENTS AND METHODS

Hormone levels were measured for patients with CRPC treated in a multicenter phase II trial of 2 estrogen-containing compounds, the herbal supplement PC-SPES and diethylstilbestrol (DES), with known efficacy in CRPC. Patients with castrate levels of testosterone were randomized to initially receive either PC-SPES 960 mg t.i.d. or DES 3 mg/day. Levels of testosterone, dihydrotestosterone (DHT), estradiol, estrone, sex hormone-binding globulin (SHBG), dehydroepiandrosterone (DHEA), DHEA-sulfate (DHEA-S), and androstenedione were obtained at baseline and at 12-week intervals until disease progression. Hormone levels were obtained for 38 patients, 20 treated with PC-SPES and 18 treated with DES.

RESULTS

Significant declines between baseline and 12 weeks of treatment were observed in levels of serum testosterone (P < .001), estrone (P = .02), and DHEA (P < .001). The percent changes at 12 weeks in these hormone levels were inversely proportional to baseline values as measured by Spearman's rank correlation (testosterone: -0.41, P = .01; estrone: -0.64, P = .0001; DHEA: -0.39, P = .02). Levels of SHBG increased in almost all of the patients (97%), with a median percent increase of > 5-fold (P < .0001). Of the 38 evaluable patients, 15 (39% [95% CI, 24%-57%]) experienced a > 50% decline in PSA level. There was no significant difference between treatment groups or between responders and nonresponders in baseline distributions for any of the hormones. At follow-up, 73% of the responders had a decline in the level of DHEA-S compared with 41% of the nonresponders, resulting in a difference in the distribution of the percent change between the subsets (Mann-Whitney test: P = .03). Conversely, 64% of the responders compared with 30% of the nonresponders experienced an increase in DHT, with differing distributions of percent change (P = .02).

CONCLUSION

Androgens decline in response to estrogen therapy. A decline in DHEA-S and a rise in DHT are both associated with a decline in PSA while patients receive estrogen therapy.

Soybean isoflavone exposure does not have feminizing effects on men: a critical examination of the clinical evidence

OBJECTIVE

To critically evaluate the clinical evidence, and when not available, the animal data, most relevant to concerns that isoflavone exposure in the form of supplements or soy foods has feminizing effects on men.

DESIGN

Medline literature review and cross-reference of published data.

RESULT(S)

In contrast to the results of some rodent studies, findings from a recently published metaanalysis and subsequently published studies show that neither isoflavone supplements nor isoflavone-rich soy affect total or free testosterone (T) levels. Similarly, there is essentially no evidence from the nine identified clinical studies that isoflavone exposure affects circulating estrogen levels in men. Clinical evidence also indicates that isoflavones have no effect on sperm or semen parameters, although only three intervention studies were identified and none were longer than 3 months in duration. Finally, findings from animal studies suggesting that isoflavones increase the risk of erectile dysfunction are not applicable to men, because of differences in isoflavone metabolism between rodents and humans and the excessively high amount of isoflavones to which the animals were exposed.

CONCLUSION(S)

The intervention data indicate that isoflavones do not exert feminizing effects on men at intake levels equal to and even considerably higher than are typical for Asian males.

A changing world for DCvax: a PSMA loaded autologous dendritic cell vaccine for prostate cancer

BACKGROUND

Northwest Therapeutics' DCvax-prostate consists of autologous dendritic cells (DCs) loaded with prostate-specific membrane antigen (PSMA) peptides, administered intravenously. Phase I-II testing, a decade ago, showed clinical benefit and immunological response in some patients. More recently DCvax brain, a product using a similar DC platform showed encouraging Phase I-II results and sipleucel-T, a prostatic acid phosphatase (PAP)-directed DC immunotherapy had positive Phase III results.

OBJECTIVE

Features of the clinical setting into which a new immunotherapy could be introduced are discussed, to refine a perspective on DCvax-prostate in the context of evolving prostate cancer therapeutics. PSMA-directed therapeutics and immune anticancer technologies are reviewed, and the clinical and immunological correlative testing of DCvax-prostate is discussed.

METHODS

Clinical and preclinical data from peer-reviewed literature, meetings proceedings and manufacturer-provided information are considered.

CONCLUSION

DCvax-prostate had encouraging early-phase trial results, but development and testing had stalled. As a more detailed understanding of patient-selection for capacity for anticancer immune response, the quantitation of immunological correlates, and the changing marketplace develop, it is appealing to consider a well tolerated, PSMA-directed autologous dendritic cell therapeutic product. Further clinical trial development of DCvax-prostate is warranted, and required if it is to find a relevant clinical application.

Assessment of herbal medicinal products: challenges, and opportunities to increase the knowledge base for safety assessment

Although herbal medicinal products (HMP) have been perceived by the public as relatively low risk, there has been more recognition of the potential risks associated with this type of product as the use of HMPs increases. Potential harm can occur via inherent toxicity of herbs, as well as from contamination, adulteration, plant misidentification, and interactions with other herbal products or pharmaceutical drugs. Regulatory safety assessment for HMPs relies on both the assessment of cases of adverse reactions and the review of published toxicity information. However, the conduct of such an integrated investigation has many challenges in terms of the quantity and quality of information. Adverse reactions are under-reported, product quality may be less than ideal, herbs have a complex composition and there is lack of information on the toxicity of medicinal herbs or their constituents. Nevertheless, opportunities exist to capitalise on newer information to increase the current body of scientific evidence. Novel sources of information are reviewed, such as the use of poison control data to augment adverse reaction information from national pharmacovigilance databases, and the use of more recent toxicological assessment techniques such as predictive toxicology and omics. The integration of all available information can reduce the uncertainty in decision making with respect to herbal medicinal products. The example of Aristolochia and aristolochic acids is used to highlight the challenges related to safety assessment, and the opportunities that exist to more accurately elucidate the toxicity of herbal medicines.

Pancreatic proteolytic enzyme therapy compared with gemcitabine-based chemotherapy for the treatment of pancreatic cancer

PURPOSE Conventional medicine has had little to offer patients with inoperable pancreatic adenocarcinoma; thus, many patients seek alternative treatments. The National Cancer Institute, in 1998, sponsored a randomized, phase III, controlled trial of proteolytic enzyme therapy versus chemotherapy. Because most eligible patients refused random assignment, the trial was changed in 2001 to a controlled, observational study. METHODS All patients were seen by one of the investigators at Columbia University, and patients who received enzyme therapy were seen by the participating alternative practitioner. Of 55 patients who had inoperable pancreatic cancer, 23 elected gemcitabine-based chemotherapy, and 32 elected enzyme treatment, which included pancreatic enzymes, nutritional supplements, detoxification, and an organic diet. Primary and secondary outcomes were overall survival and quality of life, respectively. Results At enrollment, the treatment groups had no statistically significant differences in patient characteristics, pathology, quality of life, or clinically meaningful laboratory values. Kaplan-Meier analysis found a 9.7-month difference in median survival between the chemotherapy group (median survival, 14 months) and enzyme treatment groups (median survival, 4.3 months) and found an adjusted-mortality hazard ratio of the enzyme group compared with the chemotherapy group of 6.96 (P < .001). At 1 year, 56% of chemotherapy-group patients were alive, and 16% of enzyme-therapy patients were alive. The quality of life ratings were better in the chemotherapy group than in the enzyme-treated group (P < .01). CONCLUSION Among patients who have pancreatic cancer, those who chose gemcitabine-based chemotherapy survived more than three times as long (14.0 v 4.3 months) and had better quality of life than those who chose proteolytic enzyme treatment.

The challenge of herbal therapies for prostate cancer

The paper by Singh et al. shows that silibinin inhibits prostate cancer growth in the TRAMP mouse model. Among its other properties, silibinin inhibits the progression of prostate cancer by decreasing angiogenesis and tumor invasion. Identification of the biological effects of herbal remedies such as silibinin is critical for their development as anticancer treatments.

Complications of traditional Chinese/herbal medicines (TCM)--a guide for perplexed oncologists and other cancer caregivers

INTRODUCTION

Cancer patients often seek complementary or alternative medicines to supplement or replace treatments prescribed by licensed medical practitioners. Traditional Chinese/herbal medicine (TCM) is a popular complementary intervention among cancer patients of Asian ethnicity, many of whom take it during their conventional treatment. Few of these patients inform their doctors, however, creating a risk of unexpected sequelae arising from either pharmacologic toxicity, unsuitable dosing, interactions with anti-cancer drugs or other medications, adulteration, or idiosyncratic reactions. If unrecognized, these problems may be misattributed to conventional treatment toxicity or disease progression, and remedial action may be inappropriate or delayed.

GOALS OF WORK

The purpose of this review is to help oncologists recognize the common presentations of TCM-related problems in cancer patients-such as abnormal liver function tests, unexpectedly severe myelosuppression, hemostatic defects, renal functional impairment, or suspected drug interactions-and to teach strategies by which these problems can be anticipated, prevented, or managed.

CONCLUSION

Through sensitive understanding of the reasons favoring TCM usage, oncologists can gain the trust and respect of their TCM-using patients while ensuring the safety and efficacy of conventional anticancer treatments.

Complementary and alternative medicine in present day oncology care: promises and pitfalls

Cancer is already a well-recognized global phenomenon. The traditional approaches to cancer therapy have been surgery, radiotherapy and chemotherapy. These modalities have shown considerable promise and presently form cornerstones of management of most malignancies. However, these conventional approaches have associated toxicities and suffer from limitations in curing advanced lesions. Complementary and alternative medicine (CAM), for reasons varying from cost to accessibility, has assumed significant importance in cancer therapy. In this article, we review the prominent modalities in CAM in present day cancer management and critically analyze their emerging potential into an evidence-based oncology practice.

Herbs and other botanicals in cancer patient care

OPINION STATEMENT

Non-prescription herbal remedies are commonly used by cancer patients in efforts to control their disease or to manage symptoms associated with cancer and cancer treatments. We address the issues surrounding the use of herbs, herbal compounds, and other botanical agents in the oncology context. Botanicals are biologically active agents that can be useful under appropriate circumstances, but they may be counterproductive when used by patients on chemotherapy or on other prescription medications. Herbs and other botanical agents, despite common public belief, are not benign. They should be understood as unrefined pharmaceuticals, with the capacity to produce physiologic change for better or worse. Indeed, many prescription drugs, chemotherapeutic agents among them, were derived from plants and other natural agents, and the search for additional constituents of plants, animals, and minerals for use as pharmaceutical agents remains an active effort on many fronts. Cautions, appropriate application, and potential utility of botanical agents are discussed below, and sources of reliable information are provided.

Consumption of dietary supplements and over-the-counter and prescription medications in men participating in the Prostate Cancer Prevention Trial at an academic center

OBJECTIVE

It is hypothesized that dietary patterns, individual nutrients, and specific prescription and over-the-counter medications may influence prostate carcinogenesis. Little information is available regarding the use of these products among men who are participating in prevention trials targeting prostate cancer.

MATERIALS AND METHODS

A total of 92 men (mean age 69 years) participating in the Prostate Cancer Prevention Trial (PCPT) at an academic center were asked to bring all nutritional supplements and medications to regularly scheduled study visits.

RESULTS

Data were collected on 86 of 92 men. We found that 85% of men in the PCPT regularly consumed at least 1 nutritional supplement. The mean (+/-standard deviation) number of dietary supplements consumed per man was 3.3 +/- 3.5 (range 0-21). A multivitamin and multimineral (73%) supplement was the most common product consumed. Single-nutrient supplements regularly consumed included: vitamin E (48%), vitamin C (31%), calcium (24%), and selenium (7%). Of men, 36% reported consumption of herbal products. Medications frequently consumed during the study period that may influence prostate carcinogenesis included nonsteroidal antiinflammatory drugs (57%), antihypertensives (49%), lipid lowering agents (27%), and aspirin (64%).

CONCLUSIONS

Participants in the PCPT at an academic center have a high propensity for dietary supplement use. Many, such as vitamin E and selenium, are hypothesized to influence the risk of prostate cancer. Several of the medications commonly consumed, including aspirin, nonsteroidal antiinflammatory drugs, and statins, are being investigated as chemopreventive agents. Investigators designing prostate cancer chemoprevention trials should consider including detailed documentation of exposure to these products that may influence study outcomes.

Molecular Mechanism of Anti-Prostate Cancer Activity ofScutellaria BaicalensisExtract

Scutellaria baicalensis is a widely used Chinese herbal medicine historically used in antiinflammatory and anticancer therapy. The goals of the study were to 1) determine its in vitro and in vivo anti-prostate cancer activity, 2) investigate its molecular mechanism directed at cell proliferation control including cyclooxygenase-2(COX-2) prostaglandin E2 (PGE2) and cyclins/cdks pathways, and 3) compare it with those of PC-SPES (PC stands for prostate cancer and spes is Latin for hope), a former herbal mixture for prostate cancer treatment of which S. baicalensis is a major constituent. Two human prostate cancer cell lines (LNCaP, androgen dependent, and PC-3, androgen independent) were assessed for growth inhibition. S. baicalensis exerted dose- and time-dependent increased growth inhibition in both cell lines. However, the PC-3 cells IC50 (50% growth inhibition concentration) were slightly more sensitive than LNCaP cells (IC50=0.15 mg/ml), although the former is androgen independent. S. baicalensis was more effective in inhibition of cell growth compared with PC-SPES (IC50=0.38 mg/ml for PC-3 cells). Significant reduction of PGE2 synthesis in both cells after treatment with S. baicalensis resulted from direct inhibition of COX-2 activity rather than COX-2 protein suppression. S. baicalensis also inhibited prostate-specific antigen production in LNCaP cells. Finally, S. baicalensis suppressed expression of cyclin D1 in LNCaP cells, resulting in a G1 phase arrest, while inhibiting cdk1 expression and kinase activity in PC-3 cells, ultimately leading to a G2/M cell cycle arrest. Animal studies showed a 50% reduction in tumor volume after a 7-wk treatment period. This study demonstrated that S. baicalensis may be a novel anticancer agent for the treatment of prostate cancer.

Complementary and alternative medicine for advanced prostate cancer

Complimentary and alternative medicines (CAM) have increased drastically in popularity in the past decade. These are largely in the form of nutritional supplements. Despite a wealth of information sources on the subject, the fundamental problem with CAM therapies is a dearth of evidence-based medicine. Advanced prostate cancer has significant long-term morbidity, and there is a growing interest in alternative and complimentary forms of therapy that will improve the outcomes of patients who have recurrent or advanced prostate cancer while obviating the need for more toxic forms of therapy. In this article we summarize the use of some of the more common CAM nutritional supplements and review the scientific data that are available to support their use.

Dietary agents in the chemoprevention of prostate cancer

Nutritional factors have been estimated to contribute 20-60% of cancers around the globe, and almost one-third of deaths are being reported in Western countries. According to estimates by the American Cancer Society, during the year 2005 about 232,090 new cases of prostate cancer will be diagnosed alone in the United States and 30,350 men will die of this disease. The high incidence and long latency period of prostate cancer offer plenty of time to pursue strategies toward prevention and/or treatment to suppress or revert this disease. Epidemiological evidence suggests that plant-based dietary agents decrease the risk of some types of human cancer, including prostate cancer. Intake of 400-600 g/day of fruits and vegetables is associated with reduced risk of several cancers. The use of micronutrients and/or other phenolic agents in the diet or synthetic exogenous supplements to prevent neoplastic transformation of normal cells or to slow the progression of established malignant changes in cancer cells is termed "chemoprevention." Considerable attention has been devoted to identify plant-based dietary agents that may serve as natural inhibitors of prostate carcinogenesis. Much progress has been made in the last decade in this area of investigation through identification of pathways that play important roles in prostate tumorigenesis. This article summarizes epidemiological, clinical, and mechanistic studies and the significance of plant-derived dietary agents such as flavonoids, indoles, isothiocyanates, phenolics, monoterpenes, and complementary and alternative agents in the management of prostate cancer with recommendations for future studies to advance this area of research.

Targeting angiogenesis with integrative cancer therapies

An integrative approach for managing a patient with cancer should target the multiple biochemical and physiological pathways that support tumor development while minimizing normal tissue toxicity. Angiogenesis is a key process in the promotion of cancer. Many natural health products that inhibit angiogenesis also manifest other anticancer activities. The authors will focus on natural health products (NHPs) that have a high degree of antiangiogenic activity but also describe some of their many other interactions that can inhibit tumor progression and reduce the risk of metastasis. NHPs target various molecular pathways besides angiogenesis, including epidermal growth factor receptor (EGFR), the HER-2/neu gene, the cyclooxygenase-2 enzyme, the NF-kB transcription factor, the protein kinases, Bcl-2 protein, and coagulation pathways. The herbalist has access to hundreds of years of observational data on the anticancer activity of many herbs. Laboratory studies are confirming the knowledge that is already documented in traditional texts. The following herbs are traditionally used for anticancer treatment and are antiangiogenic through multiple interdependent processes that include effects on gene expression, signal processing, and enzyme activities: Artemisia annua (Chinese wormwood), Viscum album (European mistletoe), Curcuma longa (turmeric), Scutellaria baicalensis (Chinese skullcap), resveratrol and proanthocyanidin (grape seed extract), Magnolia officinalis (Chinese magnolia tree), Camellia sinensis (green tea), Ginkgo biloba, quercetin, Poria cocos, Zingiber officinale (ginger), Panax ginseng, Rabdosia rubescens (rabdosia), and Chinese destagnation herbs. Quality assurance of appropriate extracts is essential prior to embarking on clinical trials. More data are required on dose response, appropriate combinations, and potential toxicities. Given the multiple effects of these agents, their future use for cancer therapy probably lies in synergistic combinations. During active cancer therapy, they should generally be evaluated in combination with chemotherapy and radiation. In this role, they act as biological response modifiers and adaptogens, potentially enhancing the efficacy of the so-called conventional therapies. Their effectiveness may be increased when multiple agents are used in optimal combinations. New designs for trials to demonstrate activity in human subjects are required. Although controlled trials might be preferred, smaller studies with appropriate end points and surrogate markers for antiangiogenic response could help prioritize agents for the larger resource-intensive phase 3 trials.

Unconventional anticancer agents: a systematic review of clinical trials

PURPOSE

A substantial number of cancer patients turn to treatments other than those recommended by mainstream oncologists in an effort to sustain tumor remission or halt the spread of cancer. These unconventional approaches include botanicals, high-dose nutritional supplementation, off-label pharmaceuticals, and animal products. The objective of this study was to review systematically the methodologies applied in clinical trials of unconventional treatments specifically for cancer.

METHODS

MEDLINE 1966 to 2005 was searched using approximately 200 different medical subject heading terms (eg, alternative medicine) and free text words (eg, laetrile). We sought prospective clinical trials of unconventional treatments in cancer patients, excluding studies with only symptom control or nonclinical (eg, immune) end points. Trial data were extracted by two reviewers using a standardized protocol.

RESULTS

We identified 14,735 articles, of which 214, describing 198 different clinical trials, were included. Twenty trials were phase I, three were phase I and II, 70 were phase II, and 105 were phase III. Approximately half of the trials investigated fungal products, 20% investigated other botanicals, 10% investigated vitamins and supplements, and 10% investigated off-label pharmaceuticals. Only eight of the phase I trials were dose-finding trials, and a mere 20% of phase II trials reported a statistical design. Of the 27 different agents tested in phase III, only one agent had a prior dose-finding trial, and only for three agents was the definitive study initiated after the publication of phase II data.

CONCLUSION

Unconventional cancer treatments have not been subject to appropriate early-phase trial development. Future research on unconventional therapies should involve dose-finding and phase II studies to determine the suitability of definitive trials.

Secondary Hormonal Therapy for Advanced Prostate Cancer

PURPOSE

Androgen ablation remains the cornerstone of management for advanced prostate cancer. Therapeutic options in patients with progressive disease following androgen deprivation include antiandrogen withdrawal, secondary hormonal agents and chemotherapy. Multiple secondary hormonal agents have clinical activity and the sequential use of these agents may lead to prolonged periods of clinical response. We provide a state-of-the-art review of the various agents currently used for secondary hormonal manipulation and discusses their role in the systemic treatment of patients with prostate cancer.

MATERIALS AND METHODS

A comprehensive review of the peer reviewed literature was performed on the topic of secondary hormonal therapies, including oral antiandrogens, adrenal androgen inhibitors, corticosteroids, estrogenic compounds, gonadotropin-releasing hormone antagonists and alternative hormonal therapies for advanced prostate cancer.

RESULTS

Secondary hormonal therapies can provide a safe and effective treatment option in patients with AIPC. The use of steroids and adrenolytics, such as ketoconazole and aminoglutethimide, has resulted in symptomatic improvement and a greater than 50% prostate specific antigen decrease in a substantial percent of patients with AIPC. A similar clinical benefit has been demonstrated with estrogen based therapies. Furthermore, these therapies have demonstrated a decrease in metastatic disease burden. Other novel hormonal therapies are currently under investigation and they may also show promise as secondary hormonal therapies. Finally, guidelines from the United States Food and Drug Administration Prostate Cancer Endpoints Workshop were reviewed in the context of developing new agents.

CONCLUSIONS

Secondary hormonal therapy serves as an excellent therapeutic option in patients with AIPC in whom primary hormonal therapy has failed. Practicing urologists should familiarize themselves with these oral medications, their indications and their potential side effects.

Management of Advanced Prostate Cancer After First-Line Chemotherapy

Hormone refractory prostate cancer (HRPC) causes substantial morbidity and mortality. There are increasing options for both first- and second-line therapy in the palliative treatment of patients with HRPC. Medications to control symptoms should first be optimized in patients with late-stage disease, and radiotherapy applied to dominant painful bone lesions. Docetaxel, mitoxantrone, satraplatin, and ixabepilone are active chemotherapeutic agents in the first- and/or second-line setting for patients with HRPC, and this may be true also of older drugs such as oral cyclophosphamide and vinorelbine. Radioisotopes such as strontium and samarium are useful for treatment of more generalized bone pain. Third-line hormonal maneuvers including glucocorticoids, ketoconazole, and estrogens can lead to further palliation in some patients, and there are provocative data that chemotherapy might restore hormonal sensitivity in a subset of patients.

Prior Estrogen Therapy as a Predictor of Response to Subsequent Estramustine-Based Chemotherapy in Patients with Androgen-Independent Prostate Cancer

BACKGROUND

Hormone-refractory prostate cancer (HRPC) has modest response rates to second-line estrogenic agents such as diethylstilbestrol and the herbal product PC SPES. Estramustine phosphate (EMP) is a microtubule inhibitory agent with estrogenic properties commonly used in patients with metastatic HRPC. To determine whether previous response to second-line estrogen therapy would predict subsequent response to EMP-based chemotherapy, a retrospective study was conducted.

PATIENTS AND METHODS

Patients with HRPC previously treated with second-line estrogenic therapy who subsequently received EMP-based chemotherapy were enrolled in a retrospective analysis. The progression of disease or response to treatment was determined with use of standard prostate-specific antigen (PSA) criteria and Response Evaluation Criteria in Solid Tumors.

RESULTS

Seventy-eight patients were included in the analysis. Twenty-five patients with disease progression after receiving estrogen therapy received subsequent EMP-based chemotherapy. Overall, initial PSA response to any estrogen therapy was 54%. The overall PSA response to EMP-based chemotherapy was 60%, and the objective response was 36%. The PSA response to subsequent EMP-based chemotherapy was independent of patients having a previous response to estrogen therapy (70% vs. 53%; P = 0.68). The median overall survival for patients receiving estrogenic therapy and subsequent EMP-based chemotherapy was 12.7 months.

CONCLUSION

Previous response to second-line hormonal maneuvers with estrogen therapy does not predict subsequent response to EMP-based chemotherapy.

Building an Evidence House: Challenges and Solutions to Research in Complementary and Alternative Medicine

Conventional biomedicine is having a revolution in scientific input from genomics to imaging to information and systems biology. Biomedicine is also struggling to find a balance between rigor and relevance such that public values and health care costs can be properly managed. At the same time complementary and alternative medicine (CAM) is becoming increasingly popular. Can rigorous research in CAM be developed? Can it be held to the same standards of evidence as conventional medicine? Should it be held to those standards? Are there additional standards and better integration strategies for CAM that are of value to all medicine, complementary or conventional? In this article, I address some of the major challenges faced by investigators when conducting research in CAM. These challenges include: quality standards of research; the evolving nature of science; accommodating pluralism; addressing underlying assumptions; and, managing controversial topics in CAM research. These challenges are formidable and will require that CAM attain a sufficient level of science to move it out of the margins of health care and a more careful approach to research integration that can keep its focus on public benefit and the public's health. I suggest a framework of an 'Evidence House' for addressing many of these challenges.

Contaminants of PC-SPES are not responsible for cytotoxicity in human small-cell lung carcinoma cells

PC-SPES is a mixture of herbs used in the treatment of prostate cancer. Batches of this product were found to contain traces of synthetic drugs, and the product was removed from the market. On the basis of a correlation between contaminant levels and cytotoxicity in prostate carcinoma cell lines, Sovak et al. [M. Sovak, A. Seligson, M. Konas, M. Hajduch, M. Dolezal, M. Machala, R. Nagourney, Herbal composition PC-SPES for management of prostate cancer: identification of active principles, J. Natl Cancer Inst. 94 (2002) 1275-1281] concluded that the contaminants were responsible for cytotoxicity of this preparation. Previously, we showed that extracts of PC-SPES are cytotoxic and pro-apoptotic in both drug-sensitive (H69) and drug resistant (H69V) human small-cell lung carcinoma (SCLC) cell lines. Here, we investigated whether the contaminants might be responsible for these effects. In contrast to the data reported for prostate carcinoma cells, extracts of batches of PC-SPES from the year 1998 (reportedly contaminated) and 2001 (much less contaminated) were equally cytotoxic in both SCLC cell lines. Tests of individual contaminants gave IC50 values far in excess of the amounts reported to be present in the IC50 level for the PC-SPES extracts: diethlystilbesterol: actual IC50 in H69 cells, >1000 microM; concentration present in herbal extract at IC50, 0.05-0.2 microM; indomethacin: actual IC50 in H69 cells, 800 microM; concentration in herbal extract, 1.5-20 microM; warfarin: actual IC50 in H69 cells, 950 microM; concentration in herbal extract, 0.57-0.93 microM. Adding the calculated maximum concentration of the contaminants, singly or in combination, to extracts of the less contaminated batch (2001) of PC-SPES did not alter the cytotoxicity of the extract in H69 or H69V cells. At the contaminated concentrations, as well as 5 x those concentrations, none of the contaminants was pro-apoptotic, as indicated by a DNA fragmentation kinetics assay. However, extracts of both early and late batches of PC-SPES were pro-apoptotic in SCLC cells. We conclude that the traces of pharmaceuticals found in PC-SPES were not responsible for its cytotoxic and pro-apoptotic activities of this herbal mixture on SCLC cells.

Complementary and alternative medicine use by patients enrolled onto phase I clinical trials

PURPOSE

To describe the prevalence, clinical characteristics, and pattern of use of complementary and alternative medicine (CAM) in patients enrolled onto phase I trials.

PATIENTS AND METHODS

Questionnaires were administered to 108 patients with advanced malignancies enrolled onto phase I chemotherapy trials at the Mayo Clinic Comprehensive Cancer Center (Rochester, MN). CAM was classified into two modalities, pharmacologic and nonpharmacologic. Clinical and demographic data, including age, sex, and prior cancer treatment, were subsequently obtained from patient charts and examined for any correlation with CAM use, using chi2 analysis.

RESULTS

One hundred two survey forms were returned. Among respondents, 88.2% (90 of 102) had used at least one CAM modality; 93.3% (84 of 90) and 53.3% (48 of 90) had used pharmacologic and nonpharmacologic CAM, respectively; and 46.7% (42 of 90) used both modalities. Vitamin and mineral preparations constituted 89.3% (75 of 84) of all pharmacologic CAM used. Intake was highest for vitamins E (48.8% [41 of 84]) and C (38.1% [32 of 84]), and 71.4% (60 of 84) of respondents took nonvitamin/mineral agents. Green tea (29.8% [25 of 84]), echinacea (13.1% [11 of 84]), and essiac (9.5% [8 of 84]) were the most popular. Prayer and spiritual practices were the most commonly used nonpharmacologic CAM, accounting for 52.1% (25 of 48). Chiropractors, the most frequently visited nontraditional medicine practitioners, were consulted by only 10% (9 of 90) of those who practiced CAM. Both CAM modalities were used more frequently by women (53.5% [23 of 43]) than men (40.4% [19 of 47]).

CONCLUSION

CAM use is common among patients in phase I trials and should be ascertained by investigators, because some of the agents used may interact with investigational agents and affect adverse effects and/or efficacy.