scholarly journals Activation of PI3K/AKT/mTOR Pathway Causes Drug Resistance in Breast Cancer

2021 ◽  
Vol 12 ◽  
Author(s):  
Chao Dong ◽  
Jiao Wu ◽  
Yin Chen ◽  
Jianyun Nie ◽  
Ceshi Chen
Keyword(s):  
Breast Cancer ◽  
Drug Resistance ◽  
Cancer Progression ◽  
Critical Role ◽  
Acquired Resistance ◽  
Mtor Inhibitors ◽  
Disease Recurrence ◽  
Mtor Pathway ◽  
Breast Cancer Patients

Although chemotherapy, targeted therapy and endocrine therapy decrease rate of disease recurrence in most breast cancer patients, many patients exhibit acquired resistance. Hyperactivation of the PI3K/AKT/mTOR pathway is associated with drug resistance and cancer progression. Currently, a number of drugs targeting PI3K/AKT/mTOR are being investigated in clinical trials by combining them with standard therapies to overcome acquired resistance in breast cancer. In this review, we summarize the critical role of the PI3K/AKT/mTOR pathway in drug resistance, the development of PI3K/AKT/mTOR inhibitors, and strategies to overcome acquired resistance to standard therapies in breast cancer.

scholarly journals The HIF target MAFF promotes tumor invasion and metastasis through IL11 and STAT3 signaling

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Eui Jung Moon ◽  
Stephano S. Mello ◽  
Caiyun G. Li ◽  
Jen-Tsan Chi ◽  
Kaushik Thakkar ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Tumor Invasion ◽  
Critical Role ◽  
Metastatic Breast ◽  
Breast Cancer Patients ◽  
Invasion And Metastasis ◽  
Stat3 Signaling ◽  
Inducible Genes ◽  
Transcriptional Target

AbstractHypoxia plays a critical role in tumor progression including invasion and metastasis. To determine critical genes regulated by hypoxia that promote invasion and metastasis, we screen fifty hypoxia inducible genes for their effects on invasion. In this study, we identify v-maf musculoaponeurotic fibrosarcoma oncogene homolog F (MAFF) as a potent regulator of tumor invasion without affecting cell viability. MAFF expression is elevated in metastatic breast cancer patients and is specifically correlated with hypoxic tumors. Combined ChIP- and RNA-sequencing identifies IL11 as a direct transcriptional target of the heterodimer between MAFF and BACH1, which leads to activation of STAT3 signaling. Inhibition of IL11 results in similar levels of metastatic suppression as inhibition of MAFF. This study demonstrates the oncogenic role of MAFF as an activator of the IL11/STAT3 pathways in breast cancer.

scholarly journals Antioxidants for the Treatment of Breast Cancer: Are We There Yet?

Antioxidants ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 205
Author(s):  
Carmen Griñan-Lison ◽  
Jose L. Blaya-Cánovas ◽  
Araceli López-Tejada ◽  
Marta Ávalos-Moreno ◽  
Alba Navarro-Ocón ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Oxidative Stress ◽  
Cancer Progression ◽  
Redox Homeostasis ◽  
Breast Carcinogenesis ◽  
Breast Cancer Patients ◽  
Chemopreventive Agents ◽  
Low Degree ◽  
Potential Use

Breast cancer is the most frequent cancer and the leading cause of cancer death in women. Oxidative stress and the generation of reactive oxygen species (ROS) have been related to cancer progression. Compared to their normal counterparts, tumor cells show higher ROS levels and tight regulation of REDOX homeostasis to maintain a low degree of oxidative stress. Traditionally antioxidants have been extensively investigated to counteract breast carcinogenesis and tumor progression as chemopreventive agents; however, there is growing evidence indicating their potential as adjuvants for the treatment of breast cancer. Aimed to elucidate whether antioxidants could be a reality in the management of breast cancer patients, this review focuses on the latest investigations regarding the ambivalent role of antioxidants in the development of breast cancer, with special attention to the results derived from clinical trials, as well as their potential use as plausible agents in combination therapy and their power to ameliorate the side effects attributed to standard therapeutics. Data retrieved herein suggest that antioxidants play an important role in breast cancer prevention and the improvement of therapeutic efficacy; nevertheless, appropriate patient stratification based on “redoxidomics” or tumor subtype is mandatory in order to define the dosage for future standardized and personalized treatments of patients.

scholarly journals CXCR2: A Novel Mediator of Mammary Tumor Bone Metastasis

2019 ◽  
Vol 20 (5) ◽  
pp. 1237 ◽  
Author(s):  
Bhawna Sharma ◽  
Kalyan Nannuru ◽  
Sugandha Saxena ◽  
Michelle Varney ◽  
Rakesh Singh
Keyword(s):  
Breast Cancer ◽  
Bone Metastasis ◽  
Tumor Cell ◽  
Cancer Patients ◽  
Mammary Tumor ◽  
Critical Role ◽  
Breast Cancer Patients ◽  
Mammary Tumor Cell ◽  
Primary Tumors

Most breast cancer patients die due to bone metastasis. Although metastasis accounts for 5% of the breast cancer cases, it is responsible for most of the deaths. Sometimes even before the detection of a primary tumor, most of the patients have bone and lymph node metastasis. Moreover, at the time of death, breast cancer patients have the bulk of the tumor burden in their bones. Therapy options are available for the treatment of primary tumors, but there are minimal options for treating breast cancer patients who have bone metastasis. C-X-C motif chemokine receptor type 2 (CXCR2) receptor-mediated signaling has been shown to play a critical role during bone-related inflammations and its ligands C-X-C motif chemokine ligand 6 (CXCL6) and 8 (CXCL8) aid in the resorption of bone during bone metastasis. In this study, we tested the hypothesis that CXCR2 contributes to mammary tumor-induced osteolysis and bone metastasis. In the present study, we examined the role of both tumor cell-derived and host-derived CXCR2 in influencing mammary tumor cell bone metastasis. For understanding the role of tumor cell-derived CXCR2, we utilized Cl66 CXCR2 knockdown (Cl66-shCXCR2) and Cl66-Control cells (Cl66-Control) and observed a significant decrease in tumor growth and tumor-induced osteolysis in Cl66-shCXCR2 cells in comparison with the Cl66-Control cells. Next, for understanding the role of host-derived CXCR2, we utilized mice with genomic knockdown of CXCR2 (Cxcr2−/−) and injected Cl66-Luciferase (Cl66-Luc) or 4T1-Luciferase (4T1-Luc) cells. We observed decreased bone destruction and metastasis in the bone of Cxcr2−/− mice. Our data suggest the importance of both tumor cell- and host-derived CXCR2 signaling in the bone metastasis of breast cancer cells.

scholarly journals Mechanisms of Metastasis and Cell Mobility – The Role of Metabolism

2019 ◽  
Vol 79 (02) ◽  
pp. 184-188 ◽  
Author(s):  
Carsten Gründker ◽  
Matthias Läsche ◽  
Johanna Hellinger ◽  
Günter Emons
Keyword(s):  
Breast Cancer ◽  
Cancer Progression ◽  
Early Stage ◽  
Breast Cancer Patients ◽  
Metastatic Cascade ◽  
Cell Mobility ◽  
Tumour Metastasis ◽  
Multi Stage ◽  
Mesenchymal Transformation

AbstractTumour metastasis is responsible for more than 90% of tumour-associated mortality. About one third of breast cancer patients in the early stage develop metastases. The transformation in tumour development referred to as the “metastatic cascade” or “metastatic cycle” is a complex and multi-stage event. While it is generally recognised that epithelial-mesenchymal transformation (EMT) plays a crucial role in cancer progression and metastasis, the metabolic events in this process have received little attention to date. We would therefore like to provide a brief overview here of the influence of the metabolism on the progression and metastasis of tumours.

Biopsy-driven study to identify biomarkers of drug resistance in patients with triple-negative breast cancer.

2012 ◽  
Vol 30 (30_suppl) ◽  
pp. 87-87
Author(s):  
Adriana Aguilar-Mahecha ◽  
Josiane Lafleur ◽  
Elaheh Ahmadzadeh ◽  
Ewa Przybytkowski ◽  
Carole Seguin ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Drug Resistance ◽  
Cell Lines ◽  
Triple Negative ◽  
Acquired Resistance ◽  
Great Difficulty ◽  
Clinical Samples ◽  
Drug Resistant ◽  
Breast Cancers ◽  
Breast Cancer Patients

87 Background: Resistance to chemotherapy is the underlying cause of death in most patients dying of breast cancer. Patients with early stages of breast cancer whose tumor is or becomes resistant to chemotherapy have a poor prognosis, while women with advanced breast cancer live as long as their tumors respond to chemotherapy. Because of the great difficulty of obtaining clinical samples from drug resistant tumors in patients, there is scant information about molecular factors from actual drug resistant tumors. This project aims to systematically profile resistant triple negative breast cancers (TNBCs) in order to discover molecular “resistance” genes/proteins as a first step to develop strategies to overcome drug resistance. Methods: Paired biopsies are collected from TNBC patients (NCT01276899). Four needle core biopsies are collected before the initiation of treatment and 2 weeks before surgery or at the time of progression in the neoadjuvant and metastatic settings respectively. Paired biopsies will undergo Next Gen Sequencing, flow sorted aCGH analysis, gene expression and miRNA profiling as well as phosphoproteomic profiling using reverse phase protein arrays. Results: We have currently enrolled 28 patients in the neoadjuvant setting and 3 metastatic patients. We have standardized the methods of collection and processing of tissue and blood specimens to ensure their molecular integrity and compatibility with different genomic and proteomic molecular platforms. Analysis of tumor cellularity has been incorporated into our quality control and we have optimized the extraction of nucleic acids to obtain high yields and optimal quality. In parallel, we have generated acquired resistance to paclitaxel in a panel of TNBC cell lines. These cell lines will also undergo genomic profiling and exome sequencing to identify molecular markers of resistance that will be correlated with the markers found in patient samples. Conclusions: This project will allow us to identify the molecular factors responsible for drug resistance in TNBCs and enable the elaboration of strategies to overcome resistance.

scholarly journals Cancer Cell-Derived Granulocyte-Macrophage Colony-Stimulating Factor Is Dispensable for the Progression of 4T1 Murine Breast Cancer

2019 ◽  
Vol 20 (24) ◽  
pp. 6342
Author(s):  
Teizo Yoshimura ◽  
Kaoru Nakamura ◽  
Chunning Li ◽  
Masayoshi Fujisawa ◽  
Tsuyoshi Shiina ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Tumor Microenvironment ◽  
Tumor Growth ◽  
Cancer Cell ◽  
Lung Metastasis ◽  
Cancer Progression ◽  
Critical Role ◽  
Gm Csf ◽  
4T1 Cells

We previously reported that 4T1 murine breast cancer cells produce GM-CSF that up-regulates macrophage expression of several cancer promoting genes, including Mcp-1/Ccl2, Ccl17 and Rankl, suggesting a critical role of cancer cell-derived GM-CSF in cancer progression. Here, we attempted to define whether 4T1 cell-derived GM-CSF contributes to the expression of these genes by 4T1tumors, and their subsequent progression. Intraperitoneal injection of anti-GM-CSF neutralizing antibody did not decrease the expression of Mcp-1, Ccl17 or Rankl mRNA by 4T1 tumors. To further examine the role of cancer cell-derived GM-CSF, we generated GM-CSF-deficient 4T1 cells by using the Crisper-Cas9 system. As previously demonstrated, 4T1 cells are a mixture of cells and cloning of cells by itself significantly reduced tumor growth and lung metastasis. By contrast, GM-CSF-deficiency did not affect tumor growth, lung metastasis or the expression of these chemokine and cytokine genes in tumor tissues. By in-situ hybridization, the expression of Mcp-1 mRNA was detected in both F4/80-expressing and non-expressing cells in tumors of GM-CSF-deficient cells. These results indicate that cancer cell-derived GM-CSF is dispensable for the tuning of the 4T1 tumor microenvironment and the production of MCP-1, CCL17 or RANKL in the 4T1 tumor microenvironment is likely regulated by redundant mechanisms.

scholarly journals Evaluating the expression level of HERV-K env, np9, rec and gag in breast tissue

2019 ◽  
Vol 14 (1) ◽  
Author(s):  
Shaian Tavakolian ◽  
Hossein Goudarzi ◽  
Ebrahim Faghihloo
Keyword(s):  
Breast Cancer ◽  
Cancer Progression ◽  
Breast Tissue ◽  
Mrna Level ◽  
Critical Role ◽  
Expression Level ◽  
Significant Elevation ◽  
Diagnose Breast Cancer ◽  
Cancer Tissues

Abstract Objective Breast cancer is one of the most common health problems. It has been suggested that several risk factors, either considered as external or internal, play a critical role in the pathogenesis of breast cancer, which among them, HERV-k, has the most fundamental role. In the present study, we aimed to evaluate the role of HERV-k env, gag, rec, np9 expressions in breast cancer progression. Materials and methods We collected 40 breast cancer tissues and their normal adjacent ones. After extracting the RNA of breast samples, we evaluated the expression of HERV-k env, gag, rec, np9 by using Quantitative real-time PCR (qRT-PCR). Results The resulting data revealed that while there was a meaningful increase in the expression level of HERV-k env, gag and np9 in breast cancer tissues (P ≤ 0.01, 0.05, 0.05, respectively), we failed to find any significant elevation in the expression level of rec mRNA level. Conclusion The results of our study suggested that there is a plausible correlation between the mRNA expression level of HERV-K env, gag and np9 and the progression of breast cancer, proposing these markers as promising biomarkers to diagnose breast cancer.

scholarly journals Roles for miRNAs in endocrine resistance in breast cancer

2015 ◽  
Vol 22 (5) ◽  
pp. R279-R300 ◽  
Author(s):  
Penn Muluhngwi ◽  
Carolyn M Klinge
Keyword(s):  
Breast Cancer ◽  
Estrogen Receptor ◽  
Aromatase Inhibitors ◽  
Estrogen Receptor Alpha ◽  
Acquired Resistance ◽  
Endocrine Resistance ◽  
Breast Cancer Patients ◽  
Initial Tumor ◽  
Bona Fide

Therapies targeting estrogen receptor alpha (ERα), including selective ER modulators such as tamoxifen, selective ER downregulators such as fulvestrant (ICI 182 780), and aromatase inhibitors such as letrozole, are successfully used in treating breast cancer patients whose initial tumor expresses ERα. Unfortunately, the effectiveness of endocrine therapies is limited by acquired resistance. The role of microRNAs (miRNAs) in the progression of endocrine-resistant breast cancer is of keen interest in developing biomarkers and therapies to counter metastatic disease. This review focuses on miRNAs implicated as disruptors of antiestrogen therapies, theirbona fidegene targets and associated pathways promoting endocrine resistance.

scholarly journals Differential expression of TGFβ isoforms in breast cancer highlights different roles during breast cancer progression

Tumor Biology ◽  
2018 ◽  
Vol 40 (1) ◽  
pp. 101042831774825 ◽  
Author(s):  
Mahmood Y Hachim ◽  
Ibrahim Y Hachim ◽  
Meiou Dai ◽  
Suhad Ali ◽  
Jean-Jacques Lebrun
Keyword(s):  
Breast Cancer ◽  
Cancer Patients ◽  
Cancer Progression ◽  
Molecular Subtype ◽  
Critical Role ◽  
Tumor Formation ◽  
Type I ◽  
Breast Cancer Patients ◽  
Expression Levels ◽  
Tgfβ Receptors

While TGFβ plays a critical role in tumor formation and progression, the role and contribution of its three different isoforms remain unclear. In this study, we aimed at elucidating the prognostic value of the TGFβ isoforms and assessed their expression levels in breast cancer patients at different stages of the disease. We found higher levels of TGFβ1 and TGFβ3 in cancer patients compared to normal tissues, with no significant changes in TGFβ2 expression. Similarly, TGFβ1 and TGFβ3, but not TGFβ2, showed higher expression levels in advanced lymph node–positive and metastatic tumors, suggesting different roles for the different isoforms in tumor progression and the metastatic process, while in the least aggressive molecular subtype (luminal A), expression of the three TGFβ isoforms significantly correlated with expression of both TGFβ receptors, such correlation only occurred between TGFβ1 and TGFβ3 and the TGFβ type II receptor (TβRII) in the highly aggressive basal-like subtype. Interestingly, a distinct and somehow opposite pattern was observed in HER-2 tumors, only showing significant association pattern between TGFβ2 and the TGFβ type I receptor (TβRI). Finally, the three TGFβ isoforms showed distinct association patterns with patient outcome depending on the different molecular subtype, highlighting context-dependent, differential prognostic values.

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