The Synergistic Effect of SAHA and Parthenolide in MDA-MB231 Breast Cancer Cells

The sesquiterpene lactone Parthenolide (PN) exerted a cytotoxic effect on MDA-MB231 cells, a triple-negative breast cancer (TNBC) cell line, but its effectiveness was scarce when employed at low doses. This represents an obstacle for a therapeutic utilization of PN. In order to overcome this difficulty we associated to PN the suberoylanilide hydroxamic acid (SAHA), an histone deacetylase inhibitor. Our results show that SAHA synergistically sensitized MDA-MB231 cells to the cytotoxic effect of PN. It is noteworthy that treatment with PN alone stimulated the survival pathway Akt/mTOR and the consequent nuclear translocation of Nrf2, while treatment with SAHA alone induced autophagic activity…

Parthenolide induces EGF receptor phosphorylation and superoxide anion production in MDA-MB231 breast cancer cells.

Parthenolide induces caspase-independent cell death mediated by AIF in osteosarcoma and melanoma cells.

Parthenolide, the major bioactive sesquiterpene lactone present in Feverfew (Tanacetum parthenium), has recently attracted considerable attention because of its complex pharmacological action involving anti-microbial, anti-inflammatory and anti-cancer effects. However, the mechanism of its cytotoxic effect on tumor cells still remains scarcely defined today. The aim of this study was to analyse the mechanism of parthenolide action on two lines of cancer cells, the human osteosarcoma MG63 and the melanoma SK-MEL-28 cells, on which parthenolide exerted its action inducing similar effects. Staining with Hoechst 33342 showed that parthenolide induced in the first phase of treatment (0-5 h) in m…

Parthenolide generates reactive oxygen species and autophagy in MDA-MB231 cells. A soluble parthenolide analogue inhibits tumour growth and metastasis in a xenograft model of breast cancer.

Triple-negative breast cancers (TNBCs) are clinically aggressive forms associated with a poor prognosis. We evaluated the cytotoxic effect exerted on triple-negative MDA-MB231 breast cancer cells both by parthenolide and its soluble analogue dimethylamino parthenolide (DMAPT) and explored the underlying molecular mechanism. The drugs induced a dose- and time-dependent decrement in cell viability, which was not prevented by the caspase inhibitor z-VAD-fmk. In particular in the first hours of treatment (1–3 h), parthenolide and DMAPT strongly stimulated reactive oxygen species (ROS) generation. The drugs induced production of superoxide anion by activating NADPH oxidase. ROS generation caused…

Parthenolide induces caspase-independent and AIF mediated cell death in tumor cells

The synergistic effect of SAHA and parthenolide in MDA-MB231 breast cancer cells

Abstract: The sesquiterpene lactone Parthenolide (PN) exerted a cytotoxic effect on MDA-MB231 cells, a triple-negative breast cancer (TNBC) cell line, but its effectiveness was scarce when employed at low doses. This represents an obstacle for a therapeutic utilization of PN. In order to overcome this difficulty we associated to PN the suberoylanilide hydroxamic acid (SAHA), an histone deacetylase inhibitor. Our results show that SAHA synergistically sensitized MDA-MB231 cells to the cytotoxic effect of PN. It is noteworthy that treatment with PN alone stimulated the survival pathway Akt/mTOR and the consequent nuclear translocation of Nrf2, while treatment with SAHA alone induced autophagi…

Evaluation of the in vitro and in vivo antineoplastic effects of Parthenolide on MDA-MB231 breast cancer cells

Triple-negative breast cancer refers to an aggressive subtype of breast cancer in which the tumor cells lack receptors for estrogen, progesterone and the HER2 protein on their surfaces. This type of breast cancer does not respond to treatments such as hormone therapy, like tamoxifen and aromatase inhibitors, or drugs that target HER2, like Herceptin. It is important, therefore, the identification of new selective drugs for the treatment of these tumors. Parthenolide (PN), a sesquiterpene lactone extracted from the medical plant Tanacetum parthenium, exerts anticancer activity on several tumor cell lines in culture, acting through diverse molecular mechanisms. Our previous studies have shown…

Synergistic cytotoxic interaction of the HDAC inhibitor SAHA with the natural compound parthenolide in MDA-MB231 breast cancer cells.

Il partenolide stimola la produzione di ROS e autofagia in cellule di carcinoma mammario MDA-MB231.Il suo analogo solubile DMAPT inibisce la crescita e le metastasi di xenotrapianti di tumori mammari.

Parthenolide induces caspase-independent cell death in osteosarcoma, melanoma and breast cancer cells through the induction of oxidative stress.

Parthenolide, a sesquiterpene lactone found in European feverfew, is used in traditional medicine for its anti-inflammatory activity. In addition, parthenolide has been considered as a novel and effective anti-tumor agent because it induces cytotoxic effects in several tumor cell lines. Our studies demonstrated that parthenolide exerted strong cytotoxic effects in osteosarcoma MG63 and melanoma SK-Mel28 cells in culture. Staining with Hoechst 33342 revealed in most cells after brief periods of treatments (3-5h) chromatin condensation and fragmentation, while only few cells were PI-positive. Prolonging the treatment (5-14h) PI-positive cells strongly augmented, denouncing the increase of nec…

The mechanism of parthenolide-induced cell death in tumor cell lines.

EFFETTI CITOTOSSICI DEL PARTENOLIDE IN CELLULE DI CARCINOMA MAMMARIO UMANO MDA-MB231

Il carcinoma mammario triplo negativo è una forma di carcinoma mammario particolarmente aggressiva, a prognosi spesso infausta. Tale forma tumorale è resistente alle terapie tradizionalmente impiegate per il trattamento del carcinoma mammario, pertanto risulta strettamente necessario individuare una valida strategia terapeutica. In questa tesi viene valutato l’effetto del Partenolide (PN), un composto di origine naturale, sulle cellule di carcinoma mammario umano triplo negativo MDA-MB231. I risultati ottenuti evidenziano che il PN induce morte delle cellule MDA-MB231 mediante un meccanismo caspasi-indipendente, infatti l’inibitore generale delle caspasi z-VAD non è in grado di prevenire gl…

Il partenolide induce morte in cellule di osteosarcoma umano MG63 mediante un meccanismi caspasi-indipendente, mediato da AIF.

The oxygen radicals involved in the toxicity induced by parthenolide in MDA-MB-231 cells

It has been shown that the sesquiterpene lactone parthenolide lowers the viability of MDA-MB-231 breast cancer cells, in correlation with oxidative stress. The present report examined the different radical species produced during parthenolide treatment and their possible role in the toxicity caused by the drug. Time course experiments showed that in the first phase of treatment (0-8 h), and in particular in the first 3 h, parthenolide induced dichlorofluorescein (DCF) signal in a large percentage of cells, while dihydroethidium (DHE) signal was not stimulated. Since the effect on DCF signal was suppressed by apocynin and diphenyleneiodonium (DPI), two inhibitors of NADPH oxidase (NOX), we s…

The HDAC inhibitor SAHA synergistically stimulates the cytotoxic effect induced by Parthenolide in MDA-MB231 cells

We showed that the sesquiterpene lactone Parthenolide (PN) exerts strong cytotoxic effects on triple negative breast cancer MDA-MB231 cells. Our recent results suggest that PN exerts in these cells a cytoprotective effect, which is due to the activation of mTOR pathway. To inhibit this protective response we employ the HDAC inhibitor SAHA, which is known to prevent AKT/mTOR pathway. We show that PN activates Akt, mTOR, p70S6kinase and NRF2 while SAHA abolishes these effects. Further cell pretreatment with SAHA synergistically sensitizes the cells to the cytotoxic effect of PN. Moreover SAHA alone activates the autophagic process. The addition of PN to SAHA reduces this effect and induces ap…