Zyflamend, a polyherbal mixture, down regulates class I and class II histone deacetylases and increases p21 levels in castrate-resistant prostate cancer cells.

BACKGROUND: Zyflamend, a mixture containing extracts of ten herbs, has shown promise in a variety of preclinical cancer models, including prostate cancer. The current experiments were designed to investigate the effects of Zyflamend on the expression of class I and II histone deacetylases, a family of enzymes known to be over expressed in a variety of cancers. METHODS: CWR22Rv1 cells, a castrate-resistant prostate cancer cell line, were treated with Zyflamend and the expression of class I and II histone deacetylases, along with their downstream target the tumor suppressor gene p21, was investigated. Involvement of p21 was confirmed with siRNA knockdown and over expression experiments. RESULTS: Zyflamend down-regulated the expression of all class I and II histone deacetylases where Chinese goldthread and baikal skullcap (two of its components) appear to be primarily responsible for these results. In addition, Zyflamend up regulated the histone acetyl transferase complex CBP/p300, potentially contributing to the increase in histone 3 acetylation. Expression of the tumor suppressor gene p21, a known downstream target of histone deacetylases and CBP/p300, was increased by Zyflamend treatment and the effect on p21 was, in part, mediated through Erk1/2. Knockdown of p21 with siRNA technology attenuated Zyflamend-induced growth inhibition. Over expression of p21 inhibited cell growth and concomitant treatment with Zyflamend enhanced this effect. CONCLUSIONS: Our results suggest that the extracts of this polyherbal combination increase histone 3 acetylation, inhibit the expression of class I and class II histone deacetylases, increase the activation of CBP/p300 and inhibit cell proliferation, in part, by up regulating p21 expression.

Zyflamend, a combination of herbal extracts, attenuates tumor growth in murine xenograft models of prostate cancer.

Prostate cancer (PrC) is the second deadliest cancer of males in the United States Hormone deprivation therapy (HDT), a common therapy for advanced forms of the disease, results in tumor regression; unfortunately, tumors inevitably become castrate-resistant. Diet is not an appropriate primary therapy for refractory forms of the disease; however, diet may be effective as an adjuvant to HDT, potentially extending the latency period and delaying relapse and/or inhibiting refractory growth. Zyflamend® is a combination of extracts from multiple herbs, each with reported anticancer properties. Zyflamend can inhibit growth of various PrC cell lines, but no studies have investigated its potential use in vivo using a model of castrate-resistant PrC. In this study, oral doses of Zyflamend at human equivalent doses inhibited androgen-dependent and castrate-resistant tumor growth in a mouse model that mimics advanced stages of the disease, and reduced the expression of a number of biomarkers linked to PrC progression including pAKT, prostate specific antigen, histone deacetylases, and androgen receptor. In summary, this is the first article to report that Zyflamend, when provided at human equivalent doses, can potentiate the effects of hormone deprivation on tumor regression and growth inhibition of androgen-dependent and castrate-resistant PrC tumors in vivo.

Zyflamend reduces the expression of androgen receptor in a model of castrate-resistant prostate cancer.

Prostate cancer is the most commonly diagnosed solid malignancy, and tumor cells eventually transform to castrate resistance through multiple pathways including activation of the androgen receptor via insulin-like growth factor receptor (IGF-1R) signaling involving phospho-AKT (pAKT). In this study, a mixture of herbal extracts, Zyflamend®, was used as a treatment in a model of castrate-resistant prostate cancer using CWR22Rv1 cells. Zyflamend reduced androgen receptor and IGF-1R expression along with a reduction of IGF-1-mediated proliferation of CWR22Rv1 cells. IGF-1 induced downstream AKT phosphorylation; however, the induction of pAKT was not associated with androgen receptor expression. Further, constitutively active form of AKT had no effect on nuclear expression of androgen receptor, indicating that upregulation of pAKT did not promote androgen receptor expression or nuclear translocation in castrate-resistant CWR22Rv1 cells. Conversely, Zyflamend reduced androgen receptor expression following IGF-1 stimulation and in cells overexpressing pAKT. These results demonstrated that Zyflamend inhibited IGF-1-stimulated cell growth, IGF-1R expression, and androgen receptor expression and its nuclear localization, but these effects were not dependent upon phosphatidylinositol 3-kinase/pAKT signaling. In conclusion, Zyflamend decreased cell proliferation and inhibited IGF-1R and androgen receptor expression in a phosphatidylinositol 3-kinase/pAKT independent manner.

Determinations of the antimutagenic activities of several probiotic bifidobacteria under acidic and bile conditions against benzo[a]pyrene by a modified Ames test.

Antimutagenic activities of six bifidobacteria, after acidic and bile treatment mimicking gastrointestinal conditions, against benzo[a]pyrene (B[a]P) were determined by a modified Ames test using Salmonella typhimurium TA 100. Results showed that when bifidobacteria were treated at pH 2.0 for 3 h or 1% bile for 6 h, their antimutagenic activities against B[a]P were increased as compared to controls at pH 7.0 for 0 h. After sequential acidic pH and bile treatments, Bifidobacterium lactis Bb-12 displayed the highest antimutagenic activity (71.5%), although its viable cell number was less than 2.0 log cfu/ml. The antimutagenic activity of B. lactis Bb-12 against B[a]P was increased as pH values were increased from 2.0 to 7.0, and reaction time was extended from 1 to 3 h. However, antimutagenic activity was decreased as bile salt concentration was increased from 0.5% to 2.0%. The antimutagenic activity of B. lactis Bb-12 against B[a]P was increased in the presence of whole milk (WM), semiskimmed milk (SSM) and skimmed milk (SM). When B. lactis Bb-12 was preincubated with B[a]P and milk substrates, its antimutagenic activity was increased to 99-100%.