scholarly journals FoxO3a as a Positive Prognostic Marker and a Therapeutic Target in Tamoxifen-Resistant Breast Cancer

Cancers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1858 ◽  
Author(s):  
Michele Pellegrino ◽  
Pietro Rizza ◽  
Ada Donà ◽  
Alessandra Nigro ◽  
Elena Ricci ◽  
...  

Background: Resistance to endocrine treatments is a major clinical challenge in the management of estrogen receptor positive breast cancers. Although multiple mechanisms leading to endocrine resistance have been proposed, the poor outcome of this subgroup of patients demands additional studies. Methods: FoxO3a involvement in the acquisition and reversion of tamoxifen resistance was assessed in vitro in three parental ER+ breast cancer cells, MCF-7, T47D and ZR-75-1, in the deriving Tamoxifen resistant models (TamR) and in Tet-inducible TamR/FoxO3a stable cell lines, by growth curves, PLA, siRNA, RT-PCR, Western blot, Immunofluorescence, Transmission Electron Microscopy, TUNEL, cell cycle, proteomics analyses and animal models. FoxO3a clinical relevance was validated in silico by Kaplan–Meier survival curves. Results: Here, we show that tamoxifen resistant breast cancer cells (TamR) express low FoxO3a levels. The hyperactive growth factors signaling, characterizing these cells, leads to FoxO3a hyper-phosphorylation and subsequent proteasomal degradation. FoxO3a re-expression by using TamR tetracycline inducible cells or by treating TamR with the anticonvulsant lamotrigine (LTG), restored the sensitivity to the antiestrogen and strongly reduced tumor mass in TamR-derived mouse xenografts. Proteomics data unveiled novel potential mediators of FoxO3a anti-proliferative and pro-apoptotic activity, while the Kaplan–Meier analysis showed that FoxO3a is predictive of a positive response to tamoxifen therapy in Luminal A breast cancer patients. Conclusions: Altogether, our data indicate that FoxO3a is a key target to be exploited in endocrine-resistant tumors. In this context, LTG, being able to induce FoxO3a, might represent a valid candidate in combination therapy to prevent resistance to tamoxifen in patients at risk.

2021 ◽  
pp. 1-10
Author(s):  
Yu Wang ◽  
Han Zhao ◽  
Ping Zhao ◽  
Xingang Wang

BACKGROUND: Pyruvate kinase M2 (PKM2) was overexpressed in many cancers, and high PKM2 expression was related with poor prognosis and chemoresistance. OBJECTIVE: We investigated the expression of PKM2 in breast cancer and analyzed the relation of PKM2 expression with chemotherapy resistance to the neoadjuvant chemotherapy (NAC). We also investigated whether PKM2 could reverse chemoresistance in breast cancer cells in vitro and in vivo. METHODS: Immunohistochemistry (IHC) was performed in 130 surgical resected breast cancer tissues. 78 core needle biopsies were collected from breast cancer patients before neoadjuvant chemotherapy. The relation of PKM2 expression and multi-drug resistance to NAC was compared. The effect of PKM2 silencing or overexpression on Doxorubicin (DOX) sensitivity in the MCF-7 cells in vitro and in vivo was compared. RESULTS: PKM2 was intensively expressed in breast cancer tissues compared to adjacent normal tissues. In addition, high expression of PKM2 was associated with poor prognosis in breast cancer patients. The NAC patients with high PKM2 expression had short survival. PKM2 was an independent prognostic predictor for surgical resected breast cancer and NAC patients. High PKM2 expression was correlated with neoadjuvant treatment resistance. High PKM2 expression significantly distinguished chemoresistant patients from chemosensitive patients. In vitro and in vivo knockdown of PKM2 expression decreases the resistance to DOX in breast cancer cells in vitro and tumors in vivo. CONCLUSION: PKM2 expression was associated with chemoresistance of breast cancers, and could be used to predict the chemosensitivity. Furthermore, targeting PKM2 could reverse chemoresistance, which provides an effective treatment methods for patients with breast cancer.


2020 ◽  
Vol 11 (7) ◽  
Author(s):  
Yifan Wang ◽  
Ruocen Liao ◽  
Xingyu Chen ◽  
Xuhua Ying ◽  
Guanping Chen ◽  
...  

Abstract Breast cancer is considered to be the most prevalent cancer in women worldwide, and metastasis is the primary cause of death. Protease-activated receptor 1 (PAR1) is a GPCR family member involved in the invasive and metastatic processes of cancer cells. However, the functions and underlying mechanisms of PAR1 in breast cancer remain unclear. In this study, we found that PAR1 is highly expressed in high invasive breast cancer cells, and predicts poor prognosis in ER-negative and high-grade breast cancer patients. Mechanistically, Twist transcriptionally induces PAR1 expression, leading to inhibition of Hippo pathway and activation of YAP/TAZ; Inhibition of PAR1 suppresses YAP/TAZ-induced epithelial-mesenchymal transition (EMT), invasion, migration, cancer stem cell (CSC)-like properties, tumor growth and metastasis of breast cancer cells in vitro and in vivo. These findings suggest that PAR1 acts as a direct transcriptionally target of Twist, can promote EMT, tumorigenicity and metastasis by controlling the Hippo pathway; this may lead to a potential therapeutic target for treating invasive breast cancer.


2021 ◽  
Vol 22 (20) ◽  
pp. 11273
Author(s):  
Natalia Magdalena Lisiak ◽  
Izabela Lewicka ◽  
Mariusz Kaczmarek ◽  
Jacek Kujawski ◽  
Barbara Bednarczyk-Cwynar ◽  
...  

Approximately 20–30% of the diagnosed breast cancers overexpress the human epidermal growth factor receptor 2 (HER2). This type of cancer is associated with a more aggressive phenotype; thus, there is a need for the discovery of new compounds that would improve the survival in HER2-positive breast cancer patients. It seems that one of the most promising therapeutic cancer strategies could be based on the biological activity of pentacyclic triterpenes’ derivatives and the best-known representative of this group, oleanolic acid (OA). The biological activity of oleanolic acid and its two semisynthetic derivatives, methyl 3-hydroxyimino-11-oxoolean-12-en-28-oate (HIMOXOL) and 12α-bromo-3-hydroxyimonoolean-28→13-olide (Br-HIMOLID), was assessed in SK-BR-3 breast cancer cells (HER2-positive). Viability tests, cell cycle assessment, evaluation of apoptosis, autophagy, and adhesion/migration processes were performed using MTT, clonogenic, cytofluorometry, Western blot, and qPCR. Both derivatives revealed higher cytotoxicity in studied breast cancer cells than the maternal compound, OA. They also decreased cell viability, induced autophagy, and (when applied in sub-cytotoxic concentrations) decreased the migration of SK-BR-3 cells.This study is the first to report the cytostatic, proautophagic (mTOR/LC3/SQSTM/BECN1 pathway), and anti-migratory (integrin β1/FAK/paxillin pathway) activities of HIMOXOL and Br-HIMOLID in HER2-positive breast cancer cells.


2011 ◽  
Vol 29 (27_suppl) ◽  
pp. 220-220
Author(s):  
S. Nishiya ◽  
H. Jinno ◽  
T. Hayashida ◽  
M. Takahashi ◽  
Y. Kitagawa

220 Background: The B-cell translocation gene-2 (BTG2) belongs to a class of proteins known as the Tob and BTG antiproliferative protein family. It was shown that estrogen and progesterone suppress BTG2 expression for the development of mammary gland. We demonstrated that proliferation rate of low level BTG2 expression in MCF7 was strongly inhibited by the administration of tamoxifen. In postmenopausal breast cancer patients, androgens can be converted to mitogenic estrogens by aromatase in breast cancer cells. Based on these results, we hypothesized that BTG2 expression affects the sensitivity against aromatase inhibitior. Methods: We used tetracycline-inducible BTG2 expression model in MCF7 stably transfected with the human aromatase gene (MCF7/tet/aro) as in vitro models of aromatase-driven breast cancer. The effects of BTG2 expression and administration of anastrozole in breast cancer cells were assessed by proliferation assays. Results: Administration of androstendion increased 79.1% of cellular proliferation, suggested that introduced aromatase gene worked well. Elevated level of BTG2 mRNA expression by tetracycline treatment was confirmed by Quantitative-RTPCR. Anastrozole treatment (100nM) reduced 37.8% of cellular proliferation ability, whereas the concomitant administration of tetracycline and anastorozole reduced 59.0% of cellular proliferation. These results suggested that the inhibitory effect of anastrozol for cellular proliferation was enhanced under the condition of BTG2 expression. Conclusions: Our results suggested loss of BTG2 expression may be affects the sensitivity against aromatase inhibitor.


2014 ◽  
Vol 21 (1) ◽  
pp. 101-112 ◽  
Author(s):  
Anika Nagelkerke ◽  
Anieta M Sieuwerts ◽  
Johan Bussink ◽  
Fred C G J Sweep ◽  
Maxime P Look ◽  
...  

Lysosome-associated membrane protein 3 (LAMP3) is a member of the LAMP-family of proteins, which are involved in the process of autophagy. Autophagy is induced by tamoxifen in breast cancer cells and may contribute to tamoxifen resistance. In this study, the significance of LAMP3 for tamoxifen resistance in breast cancer was examined. The methods employed included use of clonogenic assays to assess the survival of MCF7 breast cancer cells with LAMP3 knockdown after tamoxifen treatment and of quantitative real-time PCR of LAMP3 to evaluate its predictive value for first-line tamoxifen treatment in patients with advanced breast cancer. Results show that tamoxifen treatment of MCF7 cells induced LAMP3 mRNA expression. LAMP3 knockdown in these cells increased tamoxifen sensitivity. Evaluation of expression of the autophagy markers, LC3B and p62, after LAMP3 knockdown showed increased expression levels, indicating that cells with LAMP3 knockdown have a suppressed ability to complete the autophagic process. In addition, knockdown of autophagy-associated genes resulted in sensitization to tamoxifen. Next, tamoxifen-resistant MCF7 cells were cultured. These cells had a sevenfold higher LAMP3 mRNA expression, showed elevated basal autophagy levels, and could be significantly resensitized to tamoxifen by LAMP3 knockdown. In patients treated with first-line tamoxifen for advanced disease (n=304), high LAMP3 mRNA expression was associated with shorter progression-free survival (P=0.003) and shorter post-relapse overall survival (P=0.040), also in multivariate analysis. Together, these results indicate that LAMP3 contributes to tamoxifen resistance in breast cancer. Tamoxifen-resistant cells are resensitized to tamoxifen by the knockdown of LAMP3. Therefore, LAMP3 may be clinically relevant to countering tamoxifen resistance in breast cancer patients.


2019 ◽  
Author(s):  
Daniela Hühn ◽  
Pablo Martí-Rodrigo ◽  
Silvana Mouron ◽  
Catherine S. Hansel ◽  
Kirsten Tschapalda ◽  
...  

ABSTRACTEstrogen receptor (ER)-positive breast tumors are routinely treated with estrogen-depriving therapies. Despite their effectiveness, patients often progress into a more aggressive form of the disease. Through a chemical screen oriented to identify chemicals capable of inducing the expression of the immune-checkpoint ligand PD-L1, we found antiestrogens as hits. Subsequent validations confirmed that estrogen deprivation or ERα depletion induces PD-L1 expression in ER-positive breast cancer cells, both in vitro and in vivo. Likewise, PD-L1 expression is increased in metastasis arising from breast cancer patients receiving adjuvant hormonal therapy for their local disease. Transcriptome analyses indicate that estrogen deprivation triggers a broad immunosuppressive program, not restricted to PD-L1. Accordingly, estrogen deprived MCF7 cells are resistant to T-cell mediated cell killing, in a manner that can be reverted by estradiol. Our study reveals that while antiestrogen therapies effectively limit tumor growth in ER-positive breast cancers, they also trigger a transcriptional program that favors immune evasion.


2021 ◽  
Vol 11 ◽  
Author(s):  
Duanyang Zhai ◽  
Tianfu Li ◽  
Runyi Ye ◽  
Jiong Bi ◽  
Xiaying Kuang ◽  
...  

BackgroundMetastasis is a major factor weakening the long-term survival of breast cancer patients. Increasing evidence revealed that long non-coding RNAs (lncRNAs) were involved in the occurrence and development of breast cancer. In this study, we aimed to investigate the role of LGALS8-AS1 in the metastatic progression of breast cancer cells and its potential mechanisms.ResultsThe lncRNA LGALS8-AS1 was highly expressed in breast cancer and associated with poor survival. LGALS8-AS1 functioned as an oncogenic lncRNA that promoted the metastasis of breast cancer both in vitro and in vivo. It upregulated SOX12 via competing as a competing endogenous RNA (ceRNA) for sponging miR-125b-5p and acted on the PI3K/AKT signaling pathway to promote the metastasis of breast cancer. Furthermore, SOX12, in turn, activated LGALS8-AS1 expression via direct recognition of its sequence binding enrichment motif on the LGALS8-AS1 promoter, thereby forming a positive feedback regulatory loop.ConclusionThis study manifested a novel mechanism of LGALS8-AS1 facilitating the metastasis of breast cancer. The LGALS8-AS1/miR-125b-5p/SOX12 reciprocal regulatory loop dyscrasia promoted the migration and invasion of breast cancer cells. This signaling axis could be applicable to the design of novel therapeutic strategies against this malignancy.


2021 ◽  
Vol 11 (12) ◽  
pp. 2472-2477
Author(s):  
Chunxiong Fan ◽  
Yanping Deng ◽  
Yaqing Liu ◽  
Xiaoying Liu ◽  
Xi Ke ◽  
...  

Our study assessed miR-556-3p’s role in breast cancer cells. A total of 65 cases of breast cancer tissue samples were retrospectively analyzed to detect miR-556-3p level by PCR and analyze survival time and 30 normal breast tissues were included as a control group. Breast cancer cells were cultured followed by analysis of cell proliferation by MTT, cell invasion by transwell assay. miR-556-3p level was significantly upregulated in breast cancer patients compared to control group (P <0.05) and inversely associated with survival rate (P <0.05). In vitro experiments, cell activity and invasion were positively correlated with miR-556-3p level (P <0.05). In MCF-7 cell lines, miR-556-3p overexpression increased cell activity (P <0.05). Meanwhile, after miR-556-3p was overexpressed, the expression of DAB2IP, Erk, p-Erk in breast cancer cells was significantly reduced and increased after miR-556-3p was knocked down. In conclusion, miR-556-3p targets DAB2IP3′-UTR, promotes breast cancer cell proliferation, indicating that miR-556-3p might be involved in breast cancer pathogenesis and may be a new target for the treatment.


Author(s):  
Lansheng Zhang ◽  
Xia Zheng ◽  
Anqi Shen ◽  
Daojin Hua ◽  
Panrong Zhu ◽  
...  

Chemoresistance remains a major obstacle for improving the clinical outcome of patients with breast cancer. Recently, long noncoding RNAs (lncRNAs) have been implicated in breast cancer chemoresistance. However, the function and underlying mechanism are still largely unknown. Using lncRNA microarray, we identified 122 upregulated and 475 downregulated lncRNAs that might be related to the breast cancer chemoresistance. Among them, RP11-70C1.3 was one of the most highly expressed lncRNAs. In breast cancer patients, high RP11-70C1.3 expression predicted poor prognosis. Knockdown of RP11-70C1.3 inhibited the multidrug resistance of breast cancer cells in vitro and in vivo. Further investigations revealed that RP11-70C1.3 functioned as a competing endogenous RNA (ceRNA) for miR-6736-3p to increase NRP-1 expression. Notably, the rescue experiments showed that both miR-6736-3p inhibitor and NRP-1 overexpression could partly reverse the suppressive influence of RP11-70C1.3 knockdown on breast cancer chemoresistance. In conclusion, our study indicated that lncRNA RP11-70C1.3 regulated NRP-1 expression by sponging miR-6736-3p to confer chemoresistance of breast cancer cells. RP11-70C1.3 might be a potential therapeutic target in enhancing the clinical efficacy of chemotherapy in breast cancer.


2021 ◽  
Vol 12 ◽  
Author(s):  
Qin Huo ◽  
Siqi Chen ◽  
Zhenwei Li ◽  
Juan Wang ◽  
Jiaying Li ◽  
...  

Accumulating evidences indicate that transforming acidic coiled-coil 3 (TACC3) is a tumor-related gene, was highly expressed in a variety of human cancers, which is involved in cancer development. However, the potential role of TACC3 in breast cancer remains largely unknown. In the present study, we found that TACC3 was highly-expressed in breast cancer tissues, and its level was positively correlated with the clinical features of breast cancer patients. Specifically, TACC3 expression was significantly associated with the estrogen receptor (ER), progesterone receptor (PR), human epidermal growth factor receptor 2 (HER2) status, nodal status, the scarff-bloom-richardson (SBR) grade, nottingham prognostic index (NPI), age, subtypes, and triple-negative and basal-like status, suggesting that TACC3 may be a potential diagnostic indicator of breast cancer. Furthermore, functional studies have shown that inhibition of TACC3 can significantly promote the cell proliferation and viability of breast cancer cells. Moreover, TACC3 knockdown suppressed the expression of E-cadherin, but increased the expression of N-cadherin, Snail, ZEB1, and TWIST, which indicate that TACC3 may impact the migration of breast cancer cells in vitro. Taken together, these findings indicate that TACC3 may serve as a prognostic and therapeutic indicator of breast cancer.


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