Dataset Information

Citral induced apoptosis in MDA-MB-231 spheroid cells.

ABSTRACT: Breast cancer remains a leading cause of death in women worldwide. Although breast cancer therapies have greatly advanced in recent years, many patients still develop tumour recurrence and metastasis, and eventually succumb to the disease due to chemoresistance. Citral has been reported to show cytotoxic effect on various cancer cell lines. However, the potential of citral to specifically target the drug resistant breast cancer cells has not yet been tested, which was the focus of our current study.The cytotoxic activity of citral was first tested on MDA-MB-231 cells in vitro by MTT assay. Subsequently, spheroids of MDA-MB-231 breast cancer cells were developed and treated with citral at different concentrations. Doxorubicin, cisplatin and tamoxifen were used as positive controls to evaluate the drug resistance phenotype of MDA-MB-231 spheroids. In addition, apoptosis study was performed using AnnexinV/7AAD flowcytometry. Aldefluor assay was also carried out to examine whether citral could inhibit the ALDH-positive population, while the potential mechanism of the effect of citral was carried out by using quantitative real time- PCR followed by western blotting analysis.Citral was able to inhibit the growth of the MDA-MB-231 spheroids when compared to a monolayer culture of MDA-MB-231 cells at a lower IC50 value. To confirm the inhibition of spheroid self-renewal capacity, the primary spheroids were then cultured to additional passages in the absence of citral. A significant reduction in the number of secondary spheroids were formed, suggesting the reduction of self-renewal capacity of these aldehyde dehydrogenase positive (ALDH+) drug resistant spheroids. Moreover, the AnnexinV/7AAD results demonstrated that citral induced both early and late apoptotic changes in a dose-dependent manner compared to the vehicle control. Furthermore, citral treated spheroids showed lower cell renewal capacity compared to the vehicle control spheroids in the mammosphere formation assay. Gene expression studies using quantitative real time PCR and Western blotting assays showed that citral was able to suppress the self-renewal capacity of spheroids and downregulate the Wnt/?-catenin pathway.The results suggest that citral could be a potential new agent which can eliminate drug-resistant breast cancer cells in a spheroid model via inducing apoptosis.

SUBMITTER: Nigjeh SE

PROVIDER: S-EPMC5809808 | biostudies-literature | 2018 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Citral induced apoptosis in MDA-MB-231 spheroid cells.

Nigjeh Siyamak Ebrahimi SE Yeap Swee Keong SK Nordin Norshariza N Kamalideghan Behnam B Ky Huynh H Rosli Rozita R

BMC complementary and alternative medicine 20180213 1

<h4>Background</h4>Breast cancer remains a leading cause of death in women worldwide. Although breast cancer therapies have greatly advanced in recent years, many patients still develop tumour recurrence and metastasis, and eventually succumb to the disease due to chemoresistance. Citral has been reported to show cytotoxic effect on various cancer cell lines. However, the potential of citral to specifically target the drug resistant breast cancer cells has not yet been tested, which was the focu ...[more]

PMID: 29433490

Similar Datasets

Project description:Cancer cell resistance against chemotherapy is still a heavy burden to improve anticancer treatments. Autophagy activation and the development of hypoxic regions within the tumors are known to promote cancer cell resistance. Therefore, we sought to evaluate the role of autophagy and hypoxia on the taxol-induced apoptosis in MDA-MB-231 breast cancer cells. The results showed that taxol induced apoptosis after 16 h of incubation, and that hypoxia protected MDA-MB-231 cells from taxol-induced apoptosis. In parallel, taxol induced autophagy activation already after 2 h of incubation both under normoxia and hypoxia. Autophagy activation after taxol exposure was shown to be a protective mechanism against taxol-induced cell death both under normoxia and hypoxia. However, at longer incubation time, the autophagic process reached a saturation point under normoxia leading to cell death, whereas under hypoxia, autophagy flow still correctly took place allowing the cells to survive. Autophagy induction is induced after taxol exposure via mechanistic target of rapamycin (mTOR) inhibition, which is more important in cells exposed to hypoxia. Taxol also induced c-Jun N-terminal kinase (JNK) activation and phosphorylation of its substrates B-cell CLL/lymphoma 2 (Bcl2) and BCL2-like 1 (BclXL) under normoxia and hypoxia very early after taxol exposure. Bcl2 and BclXL phosphorylation was decreased more importantly under hypoxia after long incubation time. The role of JNK in autophagy and apoptosis induction was studied using siRNAs. The results showed that JNK activation promotes resistance against taxol-induced apoptosis under normoxia and hypoxia without being involved in induction of autophagy. In conclusion, the resistance against taxol-induced cell death observed under hypoxia can be explained by a more effective autophagic flow activated via the classical mTOR pathway and by a mechanism involving JNK, which could be dependent on Bcl2 and BclXL phosphorylation but independent of JNK-induced autophagy activation.

Project description:Since bone metastatic breast cancer is an incurable disease, causing significant morbidity and mortality, understanding of the underlying molecular mechanisms would be highly valuable. Here, we describe in vitro and in vivo evidence for the importance of serine biosynthesis in the metastasis of breast cancer to bone. We first characterized the bone metastatic propensity of the MDA-MB-231(SA) cell line variant as compared to the parental MDA-MB-231 cells by radiographic and histological observations in the inoculated mice. Genome-wide gene expression profiling of this isogenic cell line pair revealed that all the three genes involved in the L-serine biosynthesis pathway, phosphoglycerate dehydrogenase (PHGDH), phosphoserine aminotransferase 1 (PSAT1), and phosphoserine phosphatase (PSPH) were upregulated in the highly metastatic variant. This pathway is the primary endogenous source for L-serine in mammalian tissues. Consistently, we observed that the proliferation of MDA-MB-231(SA) cells in serine-free conditions was dependent on PSAT1 expression. In addition, we observed that L-serine is essential for the formation of bone resorbing human osteoclasts and may thus contribute to the vicious cycle of osteolytic bone metastasis. High expression of PHGDH and PSAT1 in primary breast cancer was significantly associated with decreased relapse-free and overall survival of patients and malignant phenotypic features of breast cancer. In conclusion, high expression of serine biosynthesis genes in metastatic breast cancer cells and the stimulating effect of L-serine on osteoclastogenesis and cancer cell proliferation indicate a functionally critical role for serine biosynthesis in bone metastatic breast cancer and thereby an opportunity for targeted therapeutic interventions. Parental MDA-MB-231 cells and MDA-MB-231(SA) cells were cultured in cell culture flasks. RNA was isolated in order to compare the gene expression profiles of these cell variants. Total of two samples. No replicates.

Project description:In radiation oncology, ionizing radiation is used to kill cancer cells, in other words, the induction of different types of cell death. To investigate this cellular death and the associated iron accumulation, the transfer, release, and participation of iron after radiation treatment was analyzed. We found that radiation-induced cell death varied in different breast cancer cells and autophagy was induced in MDA-MB-231 and BT549 cells (triple negative breast cancer cell line) rather than in MCF-7 and zr-75 cells. Iron chelator deferoxamine (DFO), the autophagy inhibitor 3MA, silencing of the autophagy-related genes ATG5, and Beclin 1 could decrease radiation induced cell death in MDA-MB-231 cells, while inhibitors of apoptosis such as Z-VAD-FMK, ferroptosis inhibitor ferrostatin-1 (Fer-1), and necroptosis inhibitor Necrostatin-1 showed no change. This suggests the occurrence of autophagic cell death. Furthermore, we found that iron accumulation and iron regulatory proteins, including transferrin (Tf), transferrin receptor (CD71), and Ferritin (FTH), increased after radiation treatment, and the silencing of transferrin decreased radiation-induced cell death. In addition, radiation increased lysosomal membrane permeabilization (LMP) and the release of lysosomal iron and cathepsins, while cathepsins silencing failed to change cell viability. Radiation-induced iron accumulation increased Reactive oxygen species (ROS) generation via the Fenton reaction and increased autophagy in a time-dependent manner. DFO, N-acetylcysteine (NAC), and overexpression of superoxide dismutase 2 (SOD2) decreased ROS generation, autophagy, and cell death. To summarize, for the first time, we found that radiation-induced autophagic cell death was iron-dependent in breast cancer MDA-MB-231 cells. These results provide new insights into the cell death process of cancers and might conduce to the development and application of novel therapeutic strategies for patients with apoptosis-resistant breast cancer.

Dataset Information

Citral induced apoptosis in MDA-MB-231 spheroid cells.

Publications

Citral induced apoptosis in MDA-MB-231 spheroid cells.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets