scholarly journals Suppression of poised oncogenes by ZMYND8 promotes chemo-sensitization

2020 ◽  
Vol 11 (12) ◽  
Author(s):  
Shravanti Mukherjee ◽  
Santanu Adhikary ◽  
Shrikanth S. Gadad ◽  
Payel Mondal ◽  
Sabyasachi Sen ◽  
...  

AbstractThe major challenge in chemotherapy lies in the gain of therapeutic resistance properties of cancer cells. The relatively small fraction of chemo-resistant cancer cells outgrows and are responsible for tumor relapse, with acquired invasiveness and stemness. We demonstrate that zinc-finger MYND type-8 (ZMYND8), a putative chromatin reader, suppresses stemness, drug resistance, and tumor-promoting genes, which are hallmarks of cancer. Reinstating ZMYND8 suppresses chemotherapeutic drug doxorubicin-induced tumorigenic potential (at a sublethal dose) and drug resistance, thereby resetting the transcriptional program of cells to the epithelial state. The ability of ZMYND8 to chemo-sensitize doxorubicin-treated metastatic breast cancer cells by downregulating tumor-associated genes was further confirmed by transcriptome analysis. Interestingly, we observed that ZMYND8 overexpression in doxorubicin-treated cells stimulated those involved in a good prognosis in breast cancer. Consistently, sensitizing the cancer cells with ZMYND8 followed by doxorubicin treatment led to tumor regression in vivo and revert back the phenotypes associated with drug resistance and stemness. Intriguingly, ZMYND8 modulates the bivalent or poised oncogenes through its association with KDM5C and EZH2, thereby chemo-sensitizing the cells to chemotherapy for better disease-free survival. Collectively, our findings indicate that poised chromatin is instrumental for the acquisition of chemo-resistance by cancer cells and propose ZMYND8 as a suitable epigenetic tool that can re-sensitize the chemo-refractory breast carcinoma.

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1366
Author(s):  
Russell Hughes ◽  
Xinyue Chen ◽  
Natasha Cowley ◽  
Penelope D. Ottewell ◽  
Rhoda J. Hawkins ◽  
...  

Metastatic breast cancer in bone is incurable and there is an urgent need to develop new therapeutic approaches to improve survival. Key to this is understanding the mechanisms governing cancer cell survival and growth in bone, which involves interplay between malignant and accessory cell types. Here, we performed a cellular and molecular comparison of the bone microenvironment in mouse models representing either metastatic indolence or growth, to identify mechanisms regulating cancer cell survival and fate. In vivo, we show that regardless of their fate, breast cancer cells in bone occupy niches rich in osteoblastic cells. As the number of osteoblasts in bone declines, so does the ability to sustain large numbers of breast cancer cells and support metastatic outgrowth. In vitro, osteoblasts protected breast cancer cells from death induced by cell stress and signaling via gap junctions was found to provide important juxtacrine protective mechanisms between osteoblasts and both MDA-MB-231 (TNBC) and MCF7 (ER+) breast cancer cells. Combined with mathematical modelling, these findings indicate that the fate of DTCs is not controlled through the association with specific vessel subtypes. Instead, numbers of osteoblasts dictate availability of protective niches which breast cancer cells can colonize prior to stimulation of metastatic outgrowth.


2016 ◽  
Vol 76 (18) ◽  
pp. 5209-5218 ◽  
Author(s):  
Shreyas S. Rao ◽  
Grace G. Bushnell ◽  
Samira M. Azarin ◽  
Graham Spicer ◽  
Brian A. Aguado ◽  
...  

2021 ◽  
Author(s):  
xingang wang ◽  
YAN ZHENG ◽  
YU WANG

Abstract Background and AimsPseudopodium-enriched atypical kinase 1 (PEAK1) has reported to be upregulated in human malignancies and related with poor prognosis. Enhanced PEAK1 expression facilitates tumor cell survival, invasion, metastasis and chemoresistance. However, the role of PEAK1 in breast cancer is not clear. Here, we investigated the PEAK1 expression in breast cancer and analyzed its relation with clinicopathological status and chemotherapy resistance to the neoadjuvant chemotherapy (NAC). We also investigated the role of PEAK1 on breast cancer cells in vitro and in vivo. MethodsImmunohistochemistry (IHC) was performed in 112 surgical resected breast cancer tissues. The associations between clinicopathological status, multi-drug resistance and PEAK1 expression were determined. Effect of PEAK1 overexpression or down-expression on proliferation, colony formation, invasion, migration, metastasis and Doxorubicin sensitivity in the MCF-7 cells in vitro and in vivo was detected. ResultsPEAK1 was overexpressed in breast cancer tissues and NAC -resistant breast cancer tissues. High PEAK1 expression was related with tumor size, high tumor grade, T stage, LN metastasis, recurrence, Ki-67 expression, Her-2 expression and multi-drug resistance. Targeting PEAK1 inhibited cell growth, invasion, metastasis and reversed chemoresistance to Doxorubicin in breast cancer cells in vitro and in vivo. ConclusionHigh PEAK1 expression was associated with invasion, metastasis and chemoresistance of breast cancers. Furthermore, targeting PEAK1 could inhibit cell growth and metastasis, and reverse chemoresistance in breast cancer cells, which provides an effective treatment strategies for breast cancer.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Changhu Lee ◽  
Hyung Won Ryu ◽  
Sahee Kim ◽  
Min Kim ◽  
Sei-Ryang Oh ◽  
...  

AbstractBreast cancer is one of the most common cancers in women and is associated with a high mortality rate. The majority of deaths resulting from breast cancer are attributable to metastatic growth; in addition, chemoresistance is a major concern in the treatment of patients with breast cancer. However, limited drugs are available for the treatment of metastatic breast cancer. In this study, the chemoadjuvant effects of a methanolic extract from the leaves of Pseudolysimachion rotundum var. subintegrum (NC13) and an active component isolated from the plant, verminoside (Vms), were evaluated. Furthermore, their potent anti-metastatic activities were validated in vitro and in vivo in animal models. The anti-metastatic and chemosensitizing activities of NC13 and Vms on cisplatin treatment were found to be partly mediated by suppression of the epithelial–mesenchymal transition of cancer cells. Collectively, our results implied that NC13 and its bioactive component Vms could be developed as effective chemoadjuvants in combination with conventional therapeutics.


2019 ◽  
Vol 73 ◽  
pp. 508-515 ◽  
Author(s):  
Alicja Zajdel ◽  
Daniel Wolny ◽  
Magdalena Kałucka-Janik ◽  
Adam Wilczok

Despite significant progress in the last few decades in breast cancer biology and the use of different therapeutic strategies, this cancer remains a serious clinical problem. Paclitaxel (PTX) is used to treat breast cancer both as a monotherapy and in combination with other anticancer drugs depending on the severity of the cancer, the presence of metastases and previous therapeutic management. It is characterized by high effectiveness both in early breast cancer and in metastatic breast cancer. Primary or acquired drug resistance of tumour cells to taxanes is a significant clinical problem in the treatment of various histological types of breast cancer. The main problem of resistance of tumour cells is the complexity and multifactorial nature of this phenomenon, which is conditioned by numerous different mechanisms that interact with each other. Among the known mechanisms of breast cancer cells resistance to PTX, the most important are the active removal of the drug from the cell related to the increased activity of ABC family membrane transporters, enhanced drug detoxification by cytochrome P450, CYP3A4/5 and CYP2C8 enzymes, changes within the molecular targets of PTX, microtubule and disorders of microtubule associated protein (MAPs) or apoptosis. This paper presents the latest reports on the mechanisms of drug resistance of breast cancer cells to PTX, pointing to modern strategies to counteract this adverse phenomenon.


2020 ◽  
Vol 2020 ◽  
pp. 1-10 ◽  
Author(s):  
Yunhe Lu ◽  
Lei Chen ◽  
Liangdong Li ◽  
Yiqun Cao

Brain metastasis is a major cause of death in breast cancer patients. The greatest event for brain metastasis is the breaching of the blood-brain barrier (BBB) by cancer cells. The role of exosomes in cancer metastasis is clear, whereas the role of exosomes in the integrity of the BBB is unknown. Here, we established a highly brain metastatic breast cancer cell line by three cycles of in vivo selection. The effect of exosomes on the BBB was evaluated in vitro by tracking, transepithelial/transendothelial electrical resistance (TEER), and permeability assays. BBB-associated exosomal long noncoding RNA (lncRNA) was selected from the GEO dataset and verified by real-time PCR, TEER, permeability, and Transwell assays. The cells obtained by the in vivo selection showed higher brain metastatic capacity in vivo and higher migration and invasion in vitro compared to the parental cells. Exosomes from the highly brain metastatic cells were internalized by brain microvascular endothelial cells (BMECs), which reduced TEER and increased permeability of BBB. The exosomes derived from the highly metastatic cells promoted invasion of the breast cancer cells in the BBB model. lncRNA GS1-600G8.5 was highly expressed in the highly brain metastatic cells and their exosomes, as compared to the samples with reduced metastatic behavior. Silencing of GS1-600G8.5 significantly abrogated the BBB destructive effect of exosomes. GS1-600G8.5-deficient exosomes failed to promote the infiltration of cancer cells through the BBB. Furthermore, BMECs treated with GS1-600G8.5-deprived exosomes expressed higher tight junction proteins than those treated with the control exosomes. These data suggest the exosomes derived from highly brain metastatic breast cancer cells might destroy the BBB system and promote the passage of cancer cells across the BBB, by transferring lncRNA GS1-600G8.5.


Tumor Biology ◽  
2017 ◽  
Vol 39 (3) ◽  
pp. 101042831769431 ◽  
Author(s):  
Ying Hu ◽  
Zihan Sun ◽  
Jinmu Deng ◽  
Baoquan Hu ◽  
Wenting Yan ◽  
...  

Increasing evidence has indicated that the splicing factor hnRNPA2B1 plays a direct role in cancer development, progression, gene expression, and signal transduction. Previous studies have shown that knocking down hnRNPA2B1 in breast cancer cells induces apoptosis, but the mechanism and other functions of hnRNPA2B1 in breast cancer are unknown. The goal of this study was to investigate the biological function, clinical significance, and mechanism of hnRNPA2B1 in breast cancer. The expression of hnRNPA2B1 in 92 breast cancer and adjacent normal tissue pairs was analyzed by immunohistochemical staining. Stable clones exhibiting knockdown of hnRNPA2B1 via small hairpin RNA expression were generated using RNA interference technology in breast cancer cell lines. The effects of hnRNPA2B1 on cell proliferation were examined by MTT and EdU assay, and cellular apoptosis and the cell cycle were examined by flow cytometry. A nude mouse xenograft model was established to elucidate the function of hnRNPA2B1 in tumorigenesis in vivo. The role of hnRNPA2B1 in signaling pathways was investigated in vitro. Our data revealed that hnRNPA2B1 was overexpressed in breast cancer tissue specimens and cell lines. Knockdown of hnRNPA2B1 reduced breast cancer cell proliferation, induced apoptosis, and prolonged the S phase of the cell cycle in vitro. In addition, hnRNPA2B1 knockdown suppressed subcutaneous tumorigenicity in vivo. On a molecular level, hnRNPA2B1 knockdown decreased signal transducer and activator of transcription 3 and extracellular-signal-regulated kinase 1/2 phosphorylation. We concluded that hnRNPA2B1 promotes the tumorigenic potential of breast cancer cells, MCF-7 and MDA-MB-231, through the extracellular-signal-regulated kinase 1/2 or signal transducer and activator of transcription 3 pathway, which may serve as a target for future therapies.


Nanomaterials ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 1016 ◽  
Author(s):  
Susann Piehler ◽  
Heidi Dähring ◽  
Julia Grandke ◽  
Julia Göring ◽  
Pierre Couleaud ◽  
...  

There is still a need for improving the treatment of breast cancer with doxorubicin (DOX). In this paper, we functionalized magnetic nanoparticles (MNPs) with DOX and studied the DOX-induced antitumor effects in breast cancer cells (BT474) in the presence of magnetic hyperthermia (43 °C, 1 h). We show that i) intratumoral application of DOX-functionalized MNPs (at least at a concentration of 9.6 nmol DOX/100 mm3 tumor volume) combined with magnetic hyperthermia favors tumor regression in vivo, and there is evidence for an increased effect compared to magnetic hyperthermia alone or to the intratumoral application of free DOX and ii) the presence of the pseudopeptide NucAnt (N6L) on the MNP surface might well be beneficial in its function as carrier for MNP internalization into breast cancer cells in vitro, which could further augment the possibility of the induction of intracellular heating spots and cell death in the future.


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