The inhibitory effect of curcumin via fascin suppression through JAK/STAT3 pathway on metastasis and recurrence of ovary cancer cells.

BACKGROUND: Fascin is an actin-binding protein and highly expressed in ovarian cancer cells. It is associated with metastasis of cancer and may be a useful prognostic factor. Anticancer activity of curcumin is related to its effect on several signaling mechanisms. Although there have been many reports regarding the anticancer properties of curcumin, its inhibitory effects on migration and invasion of ovarian cancer cells, particularly in the context of fascin expression, have not been reported. The purpose of this study was to investigate the effect of curcumin on fascin expression in ovarian cancer cells and to propose a possible mechanism for the anticancer activity of curcumin through reduced fascin expression. METHODS: SKOV3, human epithelial ovary cancer cell line, was cultured with curcumin at various dose and duration. The fascin was quantified using cell viability test and Western blot. To determine the effect of curcumin on the upstream pathway of fascin expression, the signal transducer and activator of transcription 3 (STAT3) was analyzed by sandwich-ELISA. Attachment assay, migration assay and invasion assay were analyzed to approve the change of cellular invasiveness of ovary cancer after curcumin. To determine the morphological changes of ovarian cancer cells by curcumin, immunofluorescence was performed. RESULTS: MTS assays showed that cell viability was different at various concentration of curcumin, and as concentration increased, cell viability tended to decrease. Curcumin appears to suppress fascin expression, even with a minimal concentration and short exposure time. Also, curcumin may suppress fascin expression in ovarian cancer cells through STAT3 downregulation. The attachment assay, migration assay and invasion assay of the ovarian cancer cells exhibited a statistically significant decrease. Immunofluorescence revealed a change of cell shape from a typical form of uninfluenced cells to a more polygonal appearance, with a significant reduction in filopodia formation. CONCLUSIONS: Curcumin reduces fascin expression through JAK/STAT3 pathway inhibition, which interferes with the cellular interactions essential for the metastasis and recurrence of ovarian cancer cells. Higher curcumin concentrations and longer exposure times concomitantly decreased fascin expression.

Vaccination with ErbB-2 peptides prevents cancer stem cell expansion and suppresses the development of spontaneous tumors in MMTV-PyMT transgenic mice.

ErbB-2 has been implicated as a target for cancer-initiating cells in breast and other cancers. ErbB-2-directed peptide vaccines have been shown to be effective in prevention of spontaneous tumorigenesis of breast in neu transgenic mouse model, and cellular immunity is proposed as a mechanism for the anti-tumor efficacy. However, there has been no explanation as to how immunity suppresses tumorigenesis from the early stage carcinogenesis, when ErbB-2 expression in breast is low. Here, we investigated a peptide-based vaccine, which consists of two MHC class II epitopes derived from murine ErbB-2, to prevent the occurrence of spontaneous tumors in breast and assess immune impact on breast cancer stem cells. Female MMTV-PyMT transgenic mice were immunized with either ErbB-2 peptide vaccine, or a peptide from tetanus toxoid, or PBS in immune adjuvant. ErbB-2 peptides vaccine completely suppressed spontaneous breast tumors, and the efficacy was correlated with antigen-specific T-cell and antibody responses. In addition, immune serum from the mice of ErbB-2 vaccine group had an inhibitory effect on mammosphere-forming capacity and signaling through ErbB-2 and downstream Akt pathway in ErbB-2 overexpressing mouse mammary cancer cells. We provide evidence that multi-epitope class II peptides vaccine suppresses tumorigenesis of breast potentially by inhibiting the growth of cancer stem cells. We also suggest that a strategy of inducing strong immune responses using multi-epitope ErbB-2-directed helper vaccine might be useful in preventing breast cancer recurrence.

Effect of curcumin on the inflammatory reaction and functional recovery after spinal cord injury in a hyperglycemic rat model.

BACKGROUND CONTEXT: Curcumin has anti-inflammatory and antioxidant activities. OBJECTIVE: This study aimed to investigate the effects of curcumin on the histological changes and functional recovery following spinal cord injury (SCI). STUDY DESIGN: One hundred twenty-eight Sprague-Dawley rats were distributed into a sham, SCI only, SCI-hyperglycemia, and SCI-hyperglycemia-curcumin (200 mg/kg/day, i.p.) groups. METHODS: SCI was induced using a clip at T9-10 and hyperglycemia was induced by streptozotocin (60-70 mg/kg, i.v.). Plasma malondialdehyde levels and superoxide dismutase activity was measured to determine oxidative stress. The activity of macrophages in the spinal cord after SCI was stained by the anti-CD68 antibody (ED-1). The tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-8 levels were measured by enzyme-linked immunosorbent assay and Western blot was used to verify the levels of mitogen-activated protein kinases and STAT3. The glial fibrillary acidic protein expression was evaluated by immunofluorescence analysis. Functional recovery was assessed according to the Basso, Beattie, and Bresnahan scale and histologic outcome was evaluated by the lesion volume and spared tissue area. RESULTS: Superoxide dismutase activity increased, the malondialdehyde level decreased, and ED-1 macrophage marker level decreased in the SCI-hyperglycemia-curcumin group than in the SCI-hyperglycemia group at 2 weeks after SCI (p<.01). The SCI-hyperglycemia-curcumin group showed a statistically significant reduction in IL-6, IL-8, and TNF-α levels compared with the SCI-hyperglycemia group after SCI. The phosphorylated-extracellular signal-regulated kinase, phosphorylated-JNK, and phospho-p38 levels were significantly lower in the SCI-hypoglycemia-curcumin group than in the SCI-hypoglycemia group. The SCI-hyperglycemia-curcumin group showed a decrease in glial fibrillary acidic protein expression after SCI compared with the SCI-hyperglycemia group. The SCI-hyperglycemia-curcumin group showed a lower lesion volume, higher spared tissue, and better functional recovery than the SCI-hyperglycemia group. CONCLUSIONS: Curcumin may have a potential neuroprotective effect in SCI with hyperglycemia. CLINICAL SIGNIFICANCE: Curcumin decreased the inflammatory response and decreased astrogliosis and improved the functional recovery and histologic outcomes in SCI with hyperglycemia.

[Corrigendum] Promoter methylation of RASSF1A modulates the effect of the microtubule-targeting agent docetaxel in breast cancer.

Following the publication of this article, an interested reader drew to our attention that there were possible anomalies in the presentation of Fig. 5B in the above article. After having examined the figure, we recognized that several errors had indeed occurred during the process of compiling the figure. A corrected version of Fig. 5 is shown below, containing new data for Fig. 5B, after our having re-performed the western blot experiment according to the identical procedure detailed in the paper. We obtained broadly similar results to those featured originally in the article; therefore, the revision of this figure does not affect the conclusions reported in the study. We thank the reader of our article who drew this matter to our attention. [the original article was published in the International Journal of Oncology 41: 611-620, 2012; DOI: 10.3892/ijo.2012.1470].

Promoter methylation of RASSF1A modulates the effect of the microtubule-targeting agent docetaxel in breast cancer.

Docetaxel is one of the most commonly used chemotherapeutic agents in breast cancer. To avert from significant toxicities with no clinical benefit, identification of predictive markers for response is one of the most important unsolved clinical needs. Therefore, the potential associations of RASSF1A hypermethylation and response to docetaxel-based chemotherapy were evaluated, and the underlying mechanism was studied. The expression of RASSF1A in breast cancer cell lines and tissues of normal breast, ductal carcinoma in situ (DCIS), and breast cancer (n=45) was analyzed by immunohistochemistry and western blot analysis. Immunohistochemical staining showed that the expression of RASSF1A was frequently lost in primary breast cancers and human breast cancer cell lines, while normal breast tissues or DCIS displayed moderate to strong expression. Furthermore, quantitative methylation analysis of the RASSF1A promoter region in 45 primary breast cancers revealed that RASSF1A was frequently methylated in primary breast cancers (≥20% methylation in 53% of the patients), and prospective analysis in patients with locally advanced or recurrent breast cancer showed that the mean level of methylation of RASSF1A was significantly higher in patients who did not respond to docetaxel-based chemotherapy (30.6±8.5%) than patients with partial or complete response (20.1±11.2%, p=0.042). Finally, in vitro studies showed that RASSF1A had cooperative activity in suppression of cancer cell growth and proliferation by enhancing docetaxel-induced cell cycle arrest. Our results suggest that hypermethylated RASSF1A is an important modulating factor for the efficacy of docetaxel-based chemotherapy in breast cancer.