Evaluation of Rhodiola crenulata on growth and metabolism of NB-1691, an MYCN-amplified neuroblastoma cell line.

Outcomes of children with high grade neuroblastoma remain poor despite multi-agent chemotherapy regimens. Rhodiola crenulata extracts display anti-neoplastic properties against several cancers including breast cancer, melanoma, and glioblastoma. In this study, we evaluated the anti-neoplastic potential of Rhodiola crenulata extracts on human neuroblastoma cells. Through this work, cell viability and proliferation were evaluated following treatments with ethanol (vehicle control) or Rhodiola crenulata extract in neuroblastoma, NB-1691 or SK-N-AS cells, in vitro. HIF-1 transcriptional activity was evaluated using a dual luciferase assay. Quantitative real-time polymerase chain reaction was utilized to assess the expression of HIF-1 targets. Selected metabolic intermediates were evaluated for their ability to rescue cells from Rhodiola crenulata extract-induced death. Lactate dehydrogenase, pyruvate kinase, and pyruvate dehydrogenase activities and NAD+/NADH levels were assayed in vehicle and Rhodiola crenulata extract-treated cells. The effects of Rhodiola crenulata extracts on metabolism were assessed by respirometry and metabolic phenotyping/fingerprinting. Our results revealed striking cytotoxic effects upon Rhodiola crenulata extract treatment, especially prominent in NB-1691 cells. As a greater response was observed in NB-1691 cells therefore it was used for remaining experiments. Upon Rhodiola crenulata extract treatment, HIF-1 transcriptional activity was increased. This increase in activity correlated with changes in HIF-1 targets involved in cellular metabolism. Serendipitously, we observed that addition of pyruvate protected against the cytotoxic effects of Rhodiola crenulata extracts. Therefore, we focused on the metabolic effects of Rhodiola crenulata extracts on NB-1691 cells. We observed that while the activities of pyruvate kinase and pyruvate dehydrogenase activities were increased, the activity of lactate dehydrogenase activity was decreased upon Rhodiola crenulata extract treatment. We also noted a decline in the total NAD pool following Rhodiola crenulata extract treatment. This correlated with decreased cellular respiration and suppressed utilization of carbon substrates. Through this work, we observed significant cytotoxic effects of Rhodiola crenulata extract treatment upon treatment on NB-1691 cells, a human neuroblastoma cell line with MYCN amplification. Our studies suggest that these cytotoxic effects could be secondary to metabolic effect induced by treatment with Rhodiola crenulata extract.

Individual-specific variation in the respiratory activities of HMECs and their bioenergetic response to IGF1 and TNFα.

Metabolic reprograming is a hallmark of cancer cells. However, the roles of pre-existing differences in normal cells metabolism toward cancer risk is not known. In order to assess pre-existing variations in normal cell metabolism, we have quantified the inter-individual variation in oxidative metabolism of normal primary human mammary epithelial cells (HMECs). We then assessed their response to selected cytokines such as insulin growth factor 1 (IGF1) and tumor necrosis factor alpha (TNFα), which are associated with breast cancer risk. Specifically, we compared the oxidative metabolism of HMECs obtained from women with breast cancer and without cancer. Our data show considerable inter-individual variation in respiratory activities of HMECs from different women. A bioenergetic parameter called pyruvate-stimulated respiration (PySR) was identified as a key distinguishing feature of HMECs from women with breast cancer and without cancer. Samples showing PySR over 20% of basal respiration rate were considered PySR+ve and the rest as PySR-ve . By this criterion, HMECs from tumor-affected breasts (AB) and non-tumor affected breasts (NAB) of cancer patients were mostly PySR-ve (88% and 89%, respectively), while HMECs from non-cancer patients were mostly PySR+ve (57%). This suggests that PySR-ve/+ve phenotypes are individual-specific and are not caused by field effects due to the presence of tumor. The effects of IGF1 and TNFα treatments on HMECs revealed that both suppressed respiration and extracellular acidification. In addition, IGF1 altered PySR-ve/+ve phenotypes. These results reveal individual-specific differences in pyruvate metabolism of normal breast epithelial cells and its association with breast cancer risk.

Evaluation of PolyMPC-Dox Prodrugs in a Human Ovarian Tumor Model.

A polymer prodrug, composed of doxorubicin (Dox) conjugated covalently to poly(methacryloyloxyethyl phosphorylcholine) (polyMPC), was evaluated for the treatment of human ovarian tumors in animals. PolyMPC-Dox prodrugs were prepared using facile conjugation chemistry to yield conjugates soluble in water and injectable saline, with a Dox loading of ∼19 weight percent. Toxicity evaluation showed that polyMPC was well-tolerated in mice at doses up to 800 mg/kg, confirming the biocompatibility of the polymer carrier at a high concentration. Additionally, the polyMPC-Dox prodrug was well-tolerated in animals at a Dox equivalent dose of 10 mg/kg, greater than twice the maximum tolerated dose of free Dox (∼4 mg/kg) in the same mouse strain. In a human ovarian tumor model (SKOV-3), polyMPC-Dox accumulated in tumors at twice the level of free Dox, with no additional off-target organ uptake, a result of improved pharmacokinetics afforded by the prodrug and passive targeting attributed to an enhanced permeability and retention effect. When administered to human ovarian tumor-bearing mice using a recurring dosing regimen comparable to that used clinically, polyMPC-Dox significantly retarded tumor growth relative to treatment with free Dox. Moreover, animals treated with multiple doses of polyMPC-Dox (eight total doses) exhibited enhanced survival, with a notably reduced incidence of toxicity or adverse events relative to mice treated with free Dox. These in vivo results demonstrate advantages of treating human ovarian tumors with polyMPC-Dox, including reduced systemic toxicity, improved drug accumulation in tumors, and enhanced therapeutic efficacy.

Antineoplastic effects of Rhodiola crenulata treatment on B16-F10 melanoma.

Melanoma is an aggressive form of skin cancer with limited treatment options for advanced stage disease. Early detection and wide surgical excision remain the initial mode of treatment for primary tumors thus preventing metastases and leading to improved prognosis. Through this work, we have evaluated the antineoplastic effects of Rhodiola crenulata (R. crenulata) root extracts on the B16-F10 melanoma cell line, both in vitro and in vivo. We observed that R. crenulata treatment resulted in increased cell death as well as a reduction in tumor cell proliferation and migration in vitro. Additionally, we observed that R. crenulata decreased the expression of integrin ß1 and vimentin and increased the expression of E-cadherin. Further, in mice treated with a topical R. crenulata-based cream therapy, tumors were more likely to have a radial growth pattern, a reduction in mitotic activity, and an increase in tumor necrosis. We also observed that mice drinking water supplemented with R. crenulata displayed a reduction of metastatic foci in disseminated models of melanoma. Collectively, these findings suggest that R. crenulata exhibits striking antitumorigenic and antimetastatic properties and that this extract may harbor potential novel adjuvant therapy for the treatment of melanoma.

Rhodiola crenulata inhibits Wnt/ß-catenin signaling in glioblastoma.

BACKGROUND: Rhodiola crenulata is a perennial plant that grows in the high altitudes of Eastern Europe and Asia. R crenulata has been used for many years in Eastern traditional medicine for a variety of medicinal purposes and it has been shown to elicit antineoplastic effects. The purpose of this study is to determine if R crenulata extract exhibits antitumor properties on glioblastoma multiforme (GBM), the most common and aggressive primary brain tumor. MATERIALS AND METHODS: Human U87 GBM cells were treated with 200 µg/mL of R crenulata or vehicle control. Cell proliferation was measured via MTS assay and clonogenic assay. The expressions of glial fibrillary acidic protein, a protein marker of differentiation, E-cadherin, and non-phospho active ß-catenin were measured with immunocytochemistry. Neurosphere assay was performed in low attachment plates. Activity of the Wnt/ß-catenin transcriptional activation was assessed via a dual-luciferase assay. RESULTS: MTS and clonogenicity assays revealed a decrease in proliferation with R crenulata therapy with an increased sensitivity to radiation. Immunocytochemistry revealed that R crenulata induced glial fibrillary acidic protein and E-cadherin expression suggestive of a more differentiated state. In agreement with the change in differentiation neurosphere formation was decreased upon treatment with R crenulata. ß-Catenin dual reporter assay revealed a decrease in Wnt promoter activity after treatment with R crenulata; this was supported by a decrease in nuclear localization of ß-catenin. CONCLUSIONS: Treatment with R crenulata extract effectively suppresses proliferation, stimulates differentiation, and eliminates tumorsphere formation of GBM cells in vitro. The observed effects are associated with inhibition of Wnt/ß-catenin signaling pathway.

GATA3 inhibits breast cancer metastasis through the reversal of epithelial-mesenchymal transition.

GATA3, a transcription factor that regulates T lymphocyte differentiation and maturation, is exclusively expressed in early stage well differentiated breast cancers but not in advanced invasive cancers. However, little is understood regarding its activity and the mechanisms underlying this differential expression in cancers. Here, we employed GATA3-positive, non-invasive (MCF-7) and GATA3-negative, invasive (MDA-MB-231) breast cancer cells to define its role in the transformation between these two distinct phenotypes. Ectopic expression of GATA3 in MDA-MB-231 cells led to a cuboidal-like epithelial phenotype and reduced cell invasive activity. These cells also increased E-cadherin expression but decreased levels of vimentin, N-cadherin, and MMP-9. Further, MDA-MB-231 cells expressing GATA3 grew smaller primary tumors without metastasis compared with larger metastatic tumors derived from control MDA-MB-231 cells in xenografted mice. GATA3 was found to induce E-cadherin expression through binding GATA-like motifs located in the E-cadherin promoter. Blockade of GATA3 using small interfering RNA gene knockdown in MCF-7 cells triggered fibroblastic transformation and cell invasion, resulting in distant metastasis. Studies of human breast cancer showed that GATA3 expression correlated with elevated E-cadherin levels, ER expression, and long disease-free survival. These data suggest that GATA3 drives invasive breast cancer cells to undergo the reversal of epithelial-mesenchymal transition, leading to the suppression of cancer metastasis.

Pathways contributing to development of spontaneous mammary tumors in BALB/c-Trp53+/- mice.

Mutation and loss of function in p53 are common features among human breast cancers. Here we use BALB/c-Trp53+/- mice as a model to examine the sequence of events leading to mammary tumors. Mammary gland proliferation rates were similar in both BALB/c-Trp53+/- mice and wild-type controls. In addition, sporadic mammary hyperplasias were rare in BALB/c-Trp53+/- mice and not detectably different from those of wild-type controls. Among the 28 mammary tumors collected from BALB/c-Trp53+/- mice, loss of heterozygosity for Trp53 was detected in more than 90% of invasive mammary tumors. Transplantation of Trp53+/- ductal hyperplasias also indicated an association between loss of the wild-type allele of Trp53 and progression to invasive carcinomas. Therefore, loss of p53 function seems to be a rate-limiting step in progression. Moreover, expression of biomarkers such as estrogen receptor alpha, progesterone receptor, Her2/Neu, and activated Notch1 varied among mammary tumors, suggesting that multiple oncogenic lesions collaborate with loss of p53 function. Expression of biomarkers was retained when tumor fragments were transplanted to syngeneic hosts. Tumors expressing solely luminal or basal keratins were also observed (27 and 11%, respectively), but the largest class of tumors expressed both luminal and basal keratins (62%). Overall, this panel of transplantable tumors provides a resource for detailed evaluation of the cell lineages undergoing transformation and preclinical testing of therapeutic agents targeting a variety of oncogenic pathways including cancer stem cells.

Preoperative leukopenia does not affect outcomes in cancer patients undergoing elective and emergent abdominal surgery: A brief report.

BACKGROUND: Leukopenic patients have historically been considered poor surgical candidates due to a perceived increase in operative morbidity and mortality. METHODS: Retrospective cohort study using the NSQIP database to identify adult patients who received chemotherapy for malignancy within 30-days prior to elective or emergent abdominal surgery between 2008 and 2011. Leukopenia was defined as < 4000 WBC/mm3 within 2-days prior to surgery. Multiple logistic regression assessed if leukopenia was associated with morbidity and mortality. RESULTS: Of the 4369 patients included, 20.2% had preoperative leukopenia. Emergency cases comprised 36.2% of cases. Overall 30-day mortality was 12.2% and 30-day composite morbidity was 29.8%. After controlling for significant confounders, including emergency status, leukopenia was not significantly associated with either postoperative mortality (p = 0.14) or morbidity (p = 0.17). CONCLUSIONS: Our study suggests that in cancer patients undergoing chemotherapy, leukopenia is not associated with morbidity or mortality and should not influence operative planning in either the elective or emergent setting.

Reduction of intestinal neoplasia with adenomatous polyposis coli gene replacement and COX-2 inhibition is additive.

Mutations of the adenomatous polyposis coli (APC) gene are implicated early in colorectal tumorigenesis. Restoration of normal APC expression through gene therapy may prevent or reduce intestinal neoplasia. Furthermore, the relationship between colorectal tumors and increased cyclooxygenase-2 (COX-2) activity provides a rationale for the use of selective COX-2 inhibitors such as rofecoxib (Vioxx) to prevent the formation of polyps. This study was performed to determine the effects of liposome-mediated APC gene therapy and a selective COX-2 inhibitor on intestinal neoplasia in vivo. Five-week-old Min mice weaned on a 30% high-fat diet were randomized to receive no treatment (control), APC only, Vioxx only, and APC/Vioxx. APC-treated mice received a plasmid containing the human APC cDNA (pCMV-APC) mixed with a liposome preparation that was administered biweekly. Vioxx was administered at 200 ppm in the high-fat rodent chow. The control mice were treated similarly with a plasmid construct lacking the APC gene. Confirmation of exogenous APC gene expression was determined by Western blot analysis. After 2 months, there was a 54% and 70% reduction in the total number of intestinal polyps after APC and Vioxx treatment, respectively. Combined APC/Vioxx therapy reduced polyp formation by 87%. The reduction of intestinal neoplasia by APC gene replacement and COX-2 inhibition suggests their separate roles in intestinal tumorigenesis. Each modality, both individually and together, may prove therapeutic and therefore contribute to new strategies in the prevention and treatment of colorectal cancer.