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Spirulina (SP) ( Arthrospira platensis ; previously Spirulina platensis ) is a filamentous blue-green microalga (cyanobacterium) with potent dietary phytoantioxidant and anticancerous properties. We investigated the chemopreventive effect of SP against 7,12-dimethylbenz[ a ]anthracene (DMBA)–induced rat breast carcinogenesis, and further studied its underlying mechanisms of action in vitro . Remarkably, SP cleared DMBA-induced rat mammary tumors, which was clearly confirmed by morphological and histological methods. SP supplementation reduced the incidence of breast tumors from 87% to 13%. At the molecular level, immunohistochemical analysis revealed that SP supplementation reduced expression of both Ki-67 and estrogen α. More interestingly, molecular analysis in the in vitro experiments indicated that SP treatment inhibited cell proliferation by 24 hours, which was accompanied by increased p53 expression, followed by increased expression of its downstream target gene, Cdkn1a (alias p21 or p21 Waf1/Cip1 ). In addition, SP increased Bax and decreased Bcl-2 expression, indicating induction of apoptosis by 48 hours after SP treatment. To our knowledge, this is the first report of in vivo chemopreventive effect of SP against DMBA-induced breast carcinogenesis in rat, supporting its potential use in chemoprevention of cancer.

Traditional chemotherapy and radiotherapy for cancer treatment face serious challenges such as drug resistance and toxic side effects. Complementary / Alternative medicine is increasingly being practiced worldwide due to its safety beneficial therapeutic effects. We hypothesized that a super combination (SC) of known phytochemicals used at bioavailable levels could induce 100% killing of breast cancer (BC) cells without toxic effects on normal cells and that microarray analysis would identify potential genes for targeted therapy of BC. Mesenchymal Stems cells (MSC, control) and two BC cell lines were treated with six well established pro-apoptotic phytochemicals individually and in combination (super cocktail), at bioavailable levels. The compounds were ineffective individually. In combination, they significantly suppressed BC cell proliferation (>80%), inhibited migration and invasion, caused cell cycle arrest and induced apoptosis resulting in 100% cell death. However, there were no deleterious effects on MSC cells used as control. Furthermore, the SC down-regulated the expression of PCNA, Rb, CDK4, BcL-2, SVV, and CD44 (metastasis inducing stem cell factor) in the BC cell lines. Microarray analysis revealed several differentially expressed key genes (PCNA, Rb, CDK4, Bcl-2, SVV, P53 and CD44) underpinning SC-promoted BC cell death and motility. Four unique genes were highly up-regulated (ARC, GADD45B, MYLIP and CDKN1C). This investigation indicates the potential for development of a highly effective phytochemical combination for breast cancer chemoprevention / chemotherapy. The novel over-expressed genes hold the potential for development as markers to follow efficacy of therapy.

Sodium nitrite (NaNO2), a food color fixative and preservative, contributes to carcinogenesis. We investigated the protective role of garlic oil against NaNO2-induced abnormalities in metabolic biochemical parameters and oxidative status in male albino rats. NaNO2 treatment for a period of three months induced a significant increase in serum levels of glucose, aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), bilirubin, urea and creatinine as well as hepatic AST and ALT. However, significant decrease was recorded in liver ALP activity, glycogen content, and renal urea and creatinine levels. In parallel, a significant increase in lipid peroxidation, and a decrease in glutathione content and catalase activity were observed in the liver and the kidney. However, garlic oil supplementation showed a remarkable amelioration of these abnormalities. Our data indicate that garlic is a phytoantioxidant with powerful chemopreventive properties against chemically-induced oxidative stress.

Cisplatin, doxorubicin and fluorouracil (5-FU), drugs belonging to different chemical classes, have been extensively used for chemotherapy of various cancers. Despite extensive investigations into their hepatotoxicity, there is very limited information on their effects on the structure and ultra-structure of liver cells in vivo. Here, we demonstrate for the first time, the effects of these three anticancer drugs on rat liver toxicity using both light and electron microscopy. Light microscopic observations revealed that higher doses of cisplatin and doxorubicin caused massive hepatotoxicity compared to 5-FU treatment, including dissolution of hepatic cords, focal inflammation and necrotic tissues. Interestingly, low doses also exhibited abnormal changes, including periportal fibrosis, degeneration of hepatic cords and increased apoptosis. These changes were confirmed at ultrastructural level, including vesiculated rough endoplasmic reticulum and atrophied mitochondria with ill-differentiated cisternae, dense collection of macrophages and lymphocytes as well as fibrocytes with collagenous fibrils manifesting early sign of fibrosis, especially in response to cisplatin and doxorubicin -treatment. Our results provide in vivo evidence, at ultrastructural level, of direct hepatotoxicity caused by cisplatin, doxorubicin and 5-FU at both light and electron microscopi. These results can guide the design of appropriate treatment regimen to reduce the hepatotoxic effects of these anticancer drugs.

Spirulina platensis (SP) is a filamentous cyanobacterium microalgae with potent dietary phyto-antioxidant, anti-inflammatory and anti-cancerous properties. The present study aimed to investigate the chemopreventive effect of SP against rat liver toxicity and carcinogenesis induced by dibutyl nitrosamine (DBN) precursors, and further characterized its underlying mechanisms of action in HepG2 cell line. Investigation by light and electron microscopy showed that DBN treatment induced severe liver injury and histopathological abnormalities, which were prevented by SP supplementation. The incidence of liver tumors was significantly reduced from 80 to 20% by SP. Immunohistochemical results indicated that both PCNA and p53 were highly expressed in the liver of DBN-treated rats, but were significantly reduced by SP supplementation. Molecular analysis indicated that SP treatment inhibited cell proliferation, which was accompanied by increased p21 and decreased Rb expression levels at 48hrs post-treatment. In addition, SP increased Bax and decreased Bcl-2 expression, indicating induction of apoptosis by 48hrs. This is the first report of the in vivo chemopreventive effect of SP against DBN-induced rat liver cytotoxicity and carcinogenesis, suggesting its potential use in chemoprevention of cancer.

While the precise mechanisms of melanoma development are unknown, recent in vivo studies have revealed that the p16(Ink4a)/Rb pathway is disrupted in melanomagenesis. Here, we characterize the role of p16/Rb in coordinating the early events in UVB-irradiated skin. Foreskins and melanoma cell cultures were irradiated with low and high acute UVB doses and examined for cell-cycle- and apoptosis-associated genes. In melanoma cells, low UVB dose upregulated p16, p53, and p21 expression levels in Malme-3M, and high UVB dose accentuated the expression of p53 and p21(Cip1/Waf1), in particular; however, in SkMel-28 cells only p16 expression was upregulated in response to UV irradiation. In HaCaT cells, high UVB dose caused dramatic increase in p53 expression followed by upregulation of p21(Cip1/Waf1) and Bax, and downregulation of Bcl-2 leading to apoptosis. In HaCaT cells, reinstatement of p16 pathway restored cell-cycle arrest in response to low dose. Foreskin organ culture experiments confirmed our in vitro cell results. These data indicate that the p53 and p16 pathways respond independently to UVB insult. The p16 pathway is favored at low doses and results in cell-cycle arrest; the p53 pathway is more responsive to higher doses and induces apoptosis depending on p53 mutation status.

Objectives A number of herbal dietary antioxidant supplements containing Indole-3 Carbinol (I3C) and Resveratrol (RE) have been established as anti-proliferative agents in cancer. These compounds have both similar as well as unique molecular targeting profiles. The purpose of this study is to analyze their mechanism of action when used individually and in combination in ovarian cancer. Methods SK-OV-3 ovarian cancer cells were treated with various doses of I3C, RE or I3C+RE. AlamarBlue dye assay was used to examine cell growth and proliferation. Cell cycle and apoptosis were analyzed by flow cytometry. Western blot was performed to determine the expression of the genes associated with cell cycle and apoptosis. CA-125, a functional marker of ovarian cancer, and nitric oxide, were analyzed by ELISA. Results I3C or RE inhibited cell proliferation, and caused cell contraction and apoptosis. Analysis of apoptosis-associated genes revealed an inhibition of Retinoblastoma protein (Rb) and Survivin (SVV) gene expression. This was accompanied by elevation of p21, a tumor suppressor. Cell cycle was inhibited at both G1 and G2/M by individual treatments, and accentuated by a combination. AlamarBlue assay revealed a clear synergistic action of I3C+RE. CA125 was inhibited by either I3C or RE treatments. In contrast, basal nitric oxide production was inhibited by I3C and I3C+RE but not RE alone. Conclusions This is the first evidence demonstrating the effects of I3C on ovarian cancer cells and its synergism with RE. Based on this model, our data indicate that combinations of compounds with different targeting properties will be more effective in chemoprevention and/or chemotherapy of ovarian and possibly other cancers.

The hyaluronan receptor CD44 plays an important role in facilitating invasion and metastasis of a variety of tumors, including breast carcinomas. CD44 functions as a bioactive signaling transmitter. Although a number of studies have implicated CD44 in breast tumor invasion, the evidence is still circumstantial. We have developed a tetracycline-regulated CD44s (standard form) system in the weakly metastatic breast cancer cell MCF7, which exhibits low endogenous expression of CD44 and generated a new cell line, MCF7F-B5. Induction of CD44s alone affected the growth characteristics of MCF7F-B5 cells by increasing their abilities to proliferate, migrate, and invade in vitro. In addition, we have identified and validated cortactin as a novel transcriptional target of hyaluronan/CD44s signaling in underpinning breast tumor invasion. To test these observations in vivo, we developed a doxycycline (DOX)-regulated CD44s breast cancer xenograft model. Induction of CD44s did not affect the growth rate or local invasion of the primary tumor. However, although no mice from the +DOX group developed metastasis, 8 of 11 mice from the -DOX group developed secondary tumors to the liver only. Interestingly, metastatic breast tumors expressed high levels of CD44. This study provides in vivo evidence for the role of the standard form of CD44 in promoting breast tumor invasion and metastasis to the liver.

The Groucho transcriptional corepressor TLE1 protein has recently been shown to be a putative lung specific oncogene, but its underlying oncogenic activity in lung cancer has not been fully elucidated. In this report, we investigated whether TLE1 regulates lung cancer aggressiveness using the human lung adenocarcinoma cell line A549 as a model system. Through a combination of genetic approaches, we found that TLE1 potentiates epithelial-to-mesenchymal transition (EMT) in A549 cells in part through suppression of the tumor suppressor gene E-cadherin. Exogenous expression of TLE1 in A549 cells resulted in heightened EMT phenotypes (enhanced fibroblastoid morphology and increased cell migratory potential) and in molecular alterations characteristic of EMT (downregulation of the epithelial marker E-cadherin and upregulation of the mesenchymal marker Vimentin). Conversely, downregulation of endogenous TLE1 expression in these cells resulted in reversal of basal EMT characterized by a cuboidal-like epithelial cell phenotype, reduced cell motility, and upregulated E-cadherin expression. Mechanistic studies showed that TLE1 suppresses E-cadherin expression at the transcriptional level in part by recruiting histone deacetylase (HDAC) activity to the E-cadherin promoter. Consistently, the HDAC inhibitor TSA partially reversed the TLE1-induced E-cadherin downregulation and cell migration, suggesting a role for HDACs in TLE1-mediated transcriptional repression of E-cadherin and EMT function. These findings uncover a novel role of TLE1 in regulating EMT in A549 cells through its repressive effect on E-cadherin and provide a mechanism for TLE1 oncogenic activity in lung cancer.

We have developed a tetracycline (tet)-off regulated expression of CD44s gene in the breast cancer (BC) cell line MCF-7 (B5 clone) and identified TGF-β2 (Transforming Growth Factor beta-2; 3 fold induction) as a potential CD44-downstream transcriptional target by microarray analysis. To further validate this finding, the same RNA samples, used for microarray analysis and their corresponding protein lysates, collected from the BC cell line MCF-7-B5, were examined for CD44 expression in the presence of HA. Our results showed that TGF-β2 mRNA levels were significantly elevated following the removal of tetracycline at 18, 24, and 48 h post-HA stimulation compared to the parental cells. Furthermore, the TGF-β2 precursor protein increased in a time-dependent pattern upon HA-stimulation and in the absence of tetracycline. More interestingly, inhibition of CD44 gene by RNAi method decreased TGF-β2 expression upon HA-stimulation, and subsequently inhibited BC cell invasion in vitro. In addition to identifying TGF-β2 as a target for HA/CD44 signaling, this data suggests that ATF/CREB might be a potential transcription factor linking HA/CD44 activation to TGF-β2 transcription and additional experiments are required for a better understanding of the molecular mechanisms underpinning the novel function of the CD44/ TGF-β2 signaling pathway in breast cancer metastasis.

The hyaluronan (HA) receptor CD44 plays an essential role in cell–cell or cell–extracellular matrix communications and is a bioactive signal transmitter. Although a number of studies have described the function of CD44 in breast cancer (BC) metastasis, the underlying mechanisms have yet to be determined. By using a validated tetracycline-off-regulated CD44 expression system in the MCF-7 cell line combined with microarray analysis, we identified survivin (SVV) as a potential downstream transcriptional target of CD44. To test the hypothesis that SVV underpins CD44-promoted BC cell invasion, we combined molecular and pharmacologic approaches and showed that CD44 induction increased SVV expression levels, which in turn promotes BC cell invasion. Further, clinical analysis of breast tissue samples showed that SVV expression patterns paralleled those of the standard form of CD44 during breast tumor progression. More interestingly, we identified the PI3K/E2F1 pathway as a potential molecular link between HA/CD44 activation and SVV transcription. In addition to identifying SVV as a target for HA/CD44 signaling, this investigation provides a better understanding of the molecular mechanisms that underpin the novel function of SVV in breast cancer metastasis.

Objective Acrylamide (ACR), a proven rodent carcinogen, is present at significantly high quantities in commonly consumed foods such as potato chips, raising a health concern worldwide. Methods The effects of ACR and fried potato chips (FPC) on pregnant mice and their offspring before and after birth were investigated and compared. Results In the pregnant mice, similar histologic abnormalities were found in various tissues for ACR intoxication and FPC supplementation. Drastic alterations were mainly seen in the liver, kidney, heart muscle, and epiphyseal cartilage of experimental dams. ACR and FPC increased the rate of abortion and neonatal mortality and decreased the total number, body weight, size, and crown–rump length of the offspring before and after birth. Interestingly, however, higher rates of congenital malformations were observed in the FPC-treated group. Although ossification of axial and appendicular bones was markedly retarded during fetal development, some ossified bones were missing in newly born offspring of treated groups. Furthermore, the incidence of missing ossification centers was higher in the FPC-treated than in the ACR-treated neonates. Conclusion These results suggest that FPC can cause hazardous health effects and warrant a systematic study on the health effects of consumption of FPC and French fries in the general population.

Obesity has been linked with an increased risk of prostate cancer. The formation of toxic free oxygen radicals has been implicated in obesity mediated disease processes. Leptin is one of the major cytokines produced by adipocytes and controls body weight homeostasis through food intake and energy expenditure. The rationale of the study was to determine the impact of leptin on the metastatic potential of androgen-sensitive (LNCaP) cells as well as androgen-insensitive (PC-3 and DU-145) cells. At a concentration of 200_nm, LNCaP cells showed a significant increase (20% above control;P<.0001) in cellular proliferation without any effect on androgen-insensitive cells. Furthermore, exposure to leptin caused a significant (P<.01toP<.0001) dose-dependent decrease in migration and invasion of PC3 and Du-145 prostate carcinoma cell lines. At the molecular level, exposure of androgen-independent prostate cancer cells to leptin stimulates the phosphorylation of MAPK at early time point as well as the transcription factor STAT3, suggesting the activation of the intracellular signaling cascade upon leptin binding to its cognate receptor. Taken together, these results suggest that leptin mediates theinvasivepotential of prostate carcinoma cells, and that this effect is dependent on their androgen sensitivity.

More than 80% of cancer related deaths are caused by cancer cell metastasis, a crucial step in the onset of tumor development. Among the molecules involved in promoting cancer metastasis is the cell adhesion molecule CD44, whose role in promoting cancer cell motility and metastasis is well known. Despite this knowledge, the molecular mechanism through which CD44 promotes tumor development and cell metastasis is still unclear. CD146 (MUC 18) is another member of the cell adhesion molecule family, first identified in highly metastatic melanomas. The absence of CD146 in normal melanocytes and its high expression in melanomas suggests its tumor promoting actions. Despite the association between CD146 expression and development of melanoma, the expression patterns and the role of CD146 in normal and metastatic breast tissues are still controversial. In this paper we provided evidence clarifying some of these discrepancies by presenting CD146 as a negative downstream target for CD44. Finally, this study demonstrates a new role of CD44 in regulating neovascularization and in promoting cancer cell transmigration of blood vessels via regulation of its downstream target CD146. Citation Format: Mohamed E. Abdraboh, Hamad Al-Riyami, Yahya Al-Farsi, Allal Ouhtit, Andrew D. Hollenbach, Ishita Gupta, Somya Shanmuganathan, Madhwa Hg Raj. CD146, a suppressor of breast cancer, is a novel target of CD44-signaling. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3302. doi:10.1158/1538-7445.AM2014-3302

Cancer cell invasion and metastasis is the worst aspect of cancer, and disruption in the cell adhesion molecules (CAM) represents the initiating event in tumor cell invasion. While the hyaluronan receptor CD44 promotes breast cancer (BC) metastasis, CD146 is a melanoma CAM that appears to suppress BC (although it promotes other cancers). In addition, the molecular mechanism by which CD146 suppresses BC is still unclear. To shed light on this discrepancy, we initially used subtractive hybridization combined with northern blotting, and identified CD146 as a potential downstream target of CD44-signaling in the MDA-435 BC cell line. Here, we provide both structural and functional evidence indicating that CD146 is a downstream target for CD44, in a way that CD146 expression is regulated according to tumor microenvironment. Finally, this study demonstrates a new role for CD44 in regulating neovascularization and promoting cancer cell transmigration of blood vessels via CD146. Citation Format: Allal Ouhtit, Mohamed E. Abdraboh, Andrew D. Hollenbach, Ishita Gupta, Somya Shanmuganathan, Madhwa HG Raj. CD146, a suppressor of breast cancer, is a novel target of CD44-signaling. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 2806. doi:10.1158/1538-7445.AM2013-2806

Cancer cell metastasis is one of the most critical steps in tumor development and is responsible for more than 80% of cancer related deaths. The cell adhesion molecule CD44 promotes cancer cell motility and metastasis. Despite this knowledge, the molecular mechanism through which CD44 promotes tumor development and cell metastasis is still unclear. The CD146 (MUC 18), another member of the cell adhesion molecules family, first identified in highly metastatic melanomas. The absence of CD146 in normal melanocytes and its high expression in melanomas suggests its tumor promoting actions. However, CD146 appears to suppress breast tumor progression. Furthermore, despite the association between CD146 expression and development of melanoma, the expression patterns and the role of CD146 in normal and metastatic breast tissues are still controversial. In a pilot study, we have identified CD146 as a potential downstream target of CD44-signaling in the MDA-435 breast cancer cell line, using subtractive hybridization and northern blot analyses. In this paper we provide evidence that CD146 is a downstream target for CD44, in a way that CD146 expression is regulated according to tumor microenvironment. Finally, this study demonstrates a new role for CD44 in regulating neovascularization and promoting cancer cell transmigration of blood vessels via CD146. Citation Format: Allal Ouhtit, Mohamed Abdraboh, Andrew D. Hollenbach, Ishita Gupta, Somya Shanmuganathan, Hamad Al Riyami, Youssef Errami, Yahya Al Farsi, Madhwa HG Raj. CD146 is a novel target of CD44-signaling mediating breast tumor invasion. [abstract]. In: Proceedings of the AACR Special Conference on Tumor Invasion and Metastasis; Jan 20-23, 2013; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2013;73(3 Suppl):Abstract nr A71.

Riboflavin carrier protein (RCP) is a growth- and development-specific protein. Here, we characterized the expression of this protein in prostate cancer by polyclonal and monoclonal antibodies against chicken RCP. RCP was localized to both androgen-dependent and independent prostate cancer cell lines. Compared to controls, RCP was over-expressed in all 45 prostate adenocarcinomas, irrespective of the Gleason's score or the stage of the disease. The identified RCP had a molecular weight of 38 kDa, similar to RCP purified from chicken. Presence of this protein was also confirmed by siRNA inhibition analysis. Antibodies to chicken RCP inhibited incorporation of tritiated thymidine into DNA and prevented riboflavin uptake in PC3 prostate cancer cells, suggesting a critical function of this protein in prostate cancer cell growth. These data suggest that RCP can be used as a tumor biomarker in prostate cancer.

Pelvic fluid was collected from 66 women undergoing laparoscopic sterilization or diagnostic laparoscopy for evaluation of infertility. Cells consisting mainly of macrophages were separated, counted, and subjected to histochemical staining for acid phosphatase and myeloperoxidase as markers of cell irritation. Pelvic fluid was analyzed for acid phosphatase, neutral protease, and extractable prostaglandin E2 and F2 alpha. A higher proportion (46% versus 15%) of the macrophages in the group with mild endometriosis exhibited positive staining for acid phosphatase as compared with the fertile group. Pelvic fluid from patients with mild endometriosis had higher acid phosphatase and neutral protease activity than that from fertile patients (p less than 0.05, p less than 0.01). The content of either prostaglandin was not significantly higher in the endometriosis group as compared with the fertile group. The results suggest that mild endometriosis is associated with activation of macrophages and release of active substances into peritoneal fluid that may be responsible for the associated infertility.

The effect of bilateral salpingectomy on ovarian function was studied in the rabbit. Nine rabbits underwent a microsurgical removal of both fallopian tubes, and nine other rabbits underwent sham operations. Four weeks after surgery the rabbits were mated, and the number of ovulation sites were recorded 18 hours after mating. Serum progesterone (P) levels were also determined prior to the operation and at 6 days and 8 days after mating. Eight days after mating the ovaries were recovered, and the corpora lutea were removed and weighed. The mean number and weights of corpora lutea as well as serum P levels did not differ significantly between the groups. These findings suggest that the absence of fallopian tubes has no effect on subsequent ovulatory function in this animal model.

A patient with the resistant ovary syndrome is reported. To evaluate the hypothesis that the hypogonadism might be the result of circulating antibodies to gonadotropin receptors or to an abnormal gonadotropin molecule, a series of clinical and laboratory studies was carried out. Administration of human menopausal gonadotropin had no effect on the serum estradiol level. The patient's serum did not affect follicle-stimulating hormone binding to a membrane preparation of monkey testes, suggesting the absence of antibodies to follicle-stimulating hormone receptors, nor did the patient's serum affect in vitro responsiveness of human granulosa cells to human menopausal gonadotropin. Unresponsiveness to exogenous gonadotropins, combined with anatomically normal follicular apparatus and the absence of serum antibodies to gonadotropin receptors, supports the concept of a gonadotropin receptor or a postreceptor defect.

Oral contraceptives reduce the elevated androgen levels in polycystic ovary disease. However, treatment with oral contraceptives is associated with undesirable side effects because of their high estrogen content. This study was undertaken to examine the effects of low estrogen-containing oral contraceptive (Loestrin:norethindrone acetate 1.5 mg and ethinyl estradiol 30 micrograms) on 25 women with polycystic ovary disease of ovarian origin. Loestrin treatment normalized the elevated luteinizing hormone and total and unbound testosterone levels and increased testosterone binding globulin levels. In a time-course study, unbound testosterone declined within a week of initiating treatment and by 12 to 16 weeks was completely normal. Reduction in hair growth and improvement in complexion were noted by about 12 to 16 weeks. Side effects of treatment were minimal.