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 prevents resistance of MDA-MB231 cells to doxorubicin and mitoxantrone: the role of Nrf2.

Triple-negative breast cancer is a group of aggressive cancers with poor prognosis owing to chemoresistance, recurrence and metastasis. New strategies are required that could reduce chemoresistance and increases the effectiveness of chemotherapy. The results presented in this paper, showing that parthenolide (PN) prevents drug resistance in MDA-MB231 cells, represent a contribution to one of these possible strategies. MDA-MB231 cells, the most studied line of TNBC cells, were submitted to selection treatment with mitoxantrone (Mitox) and doxorubicin (DOX). The presence of resistant cells was confirmed through the measurement of the resistance index. Cells submitted to this treatment exhibit…

EFFETTI CITOTOSSICI SINERGICI INDOTTI DALLA COMBINAZIONE SAHA/PARTENOLIDE IN CELLULE DI CARCINOMA MAMMARIO UMANO MDA-MB231

Il Partenolide (PN) è un sesquiterpene lattone, estratto dalla pianta medicinale Tanacetum Parthenium, noto per le sue proprietà antiinfiammatorie, antimicrobiche e antitumorali. A tal proposito, recentemente è stato dimostrato che il PN è in grado di esercitare un potente effetto citotossico in cellule di “carcinoma mammario umano triplo negativo” (TNBC) MDA-MB231. Tuttavia quando il composto è impiegato a basse dosi determina effetti citotossici molto limitati, anche dopo lunghi periodi di trattamento. Questi risultati suggeriscono che il PN nelle cellule MDA-MB231 è in grado di indurre effetti citoprotettivi che si evidenziano quando impiegato a basse dosi. Poiché tale caratteristica pot…

The cytotoxic effect exerted by parthenolide and DMAPT on breast cancer stem-like cells

Triple-negative breast cancers (TNBCs) are aggressive forms of breast carcinoma associated with a high rate of recidivism. It is known that a small proportion of tumour cells, termed cancer stem cells (CSCs), is responsible for tumour formation, progression and recurrence. The sesquiterpene lactone parthenolide (PN) was identified as the first small molecule capable of killing CSCs.1 Previously we have shown2 that PN and its soluble analogue DMAPT induce a strong cytotoxic effect in MDA-MB231 cells, the most studied line of TNBCs. In the present research we investigated about the effects exerted by both PN and DMAPT on breast cancer stem-like cells derived from three lines of TNBCs (MDA-MB2…

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.

Synergistic effect of the HDAC inhibitor SAHA and the sesquiterpene lactone parthenolide in triple negative 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.

Retinoblastoma: History of His Identification, Characterization and Treatment

The first description of a tumor resembling retinoblastoma (RB) was provided on 1597 by Pieter Pauw, who described a malignancy invading the orbit, the temporal region, and the cranium, filled with a "substance similar to brain tissue mixed with thick blood and like crushed stone". Since then, a number of retinal tumors were described and named until the 1922 when Verhoeff called these tumors RB, a term that the American Ophthalmological Society adopted in 1926. In 1971 Knudson focused on RB, and proposed his ‘two-hit’ theory of the molecular etiology of RB. In 1986, the RB1 gene was identified and the ‘two-hit’ theory of Knudson was validated. Successively, new studies in developing retina…

Parthenolide and DMAPT exert cytotoxic effects on breast cancer stem-like cells by inducing oxidative stress, mitochondrial dysfunction and necrosis

Triple-negative breast cancers (TNBCs) are aggressive forms of breast carcinoma associated with a high rate of recidivism. In this paper, we report the production of mammospheres from three lines of TNBC cells and demonstrate that both parthenolide (PN) and its soluble analog dimethylaminoparthenolide (DMAPT) suppressed this production and induced cytotoxic effects in breast cancer stem-like cells, derived from dissociation of mammospheres. In particular, the drugs exerted a remarkable inhibitory effect on viability of stem-like cells. Such an effect was suppressed by N-acetylcysteine, suggesting a role of reactive oxygen species (ROS) generation in the cytotoxic effect. Instead z-VAD, a ge…

Parthenolide induces superoxide anion production by stimulating EGF receptor in MDA-MB-231 breast cancer cells

The sesquiterpene lactone parthenolide (PN) has recently attracted considerable attention because of its anti-microbial, anti-inflammatory and anticancer effects. However, the mechanism of its cytotoxic action on tumor cells remains scarcely defined. We recently provided evidence that the effect exerted by PN in MDA-MB-231 breast cancer cells was mediated by the production of reactive oxygen species (ROS). The present study shows that PN promoted the phosphorylation of EGF receptor (phospho-EGFR) at Tyr1173, an event which was observed already at 1  h of incubation with 25  µM PN and reached a peak at 8-16  h. This effect seemed to be a consequence of ROS production, because N-acetylcystein…

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…