scholarly journals Gpn3 Is Essential for Cell Proliferation of Breast Cancer Cells Independent of Their Malignancy Degree

2019 ◽  
Vol 18 ◽  
pp. 153303381987082 ◽  
Author(s):  
Bárbara Lara-Chacón ◽  
Sandra L. Guerrero-Rodríguez ◽  
Karla J. Ramírez-Hernández ◽  
Angélica Yamilett Robledo-Rivera ◽  
Marco Antonio Velasco Velazquez ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Proliferation ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Cell Lines ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Cellular Models ◽  
Her2 Breast Cancer ◽  
Public Data

Successful therapies for patients with breast cancer often lose their initial effectiveness. Thus, identifying new molecular targets is a constant goal in the fight against breast cancer. Gpn3 is a protein required for RNA polymerase II nuclear targeting in both yeast and human cells. We investigated here the effect of suppressing Gpn3 expression on cell proliferation in a progression series of isogenic cell lines derived from the nontumorigenic MCF-10A breast cells that recapitulate different stages of breast carcinogenesis. Gpn3 protein levels were comparable in all malignant derivatives of the nontumorigenic MCF-10A cells. shRNA-mediated inhibition of Gpn3 expression markedly decreased cell proliferation in all MCF-10A sublines. A fraction of the largest RNA polymerase II subunit Rpb1 was retained in the cytoplasm, but most Rpb1 remained nuclear after suppressing Gpn3 in all cell lines studied. Long-term proliferation experiments in cells with suppressed Gpn3 expression resulted in the eventual loss of all isogenic cell lines but MCF-10CA1d.cl1. In MCF-10CA1d.cl1 cells, Gpn3 knockdown reduced the proliferation of breast cancer stem cells as evaluated by mammosphere assays. After the identification that Gpn3 plays a key role in cell proliferation in mammary epithelial cells independent of the degree of transformation, we also analyzed the importance of Gpn3 in other human breast cancer cell lines from different subtypes. Gpn3 was also required for cell proliferation and nuclear translocation of RNA polymerase II in such cellular models. Altogether, our results show that Gpn3 is essential for breast cancer cell proliferation regardless of the transformation level, indicating that Gpn3 could be considered a molecular target for the development of new antiproliferative therapies. Importantly, our analysis of public data revealed that Gpn3 overexpression was associated with a significant decrease in overall survival in patients with estrogen receptor-positive and Human epidermal growth factor receptor 2 (HER2+) breast cancer, supporting our proposal that targeting Gpn3 could potentially benefit patients with breast cancer.

scholarly journals Highly expressed SLCO1B3 inhibits the occurrence and development of breast cancer and can be used as a clinical indicator of prognosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tiantian Tang ◽  
Guiying Wang ◽  
Sihua Liu ◽  
Zhaoxue Zhang ◽  
Chen Liu ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Proliferation ◽  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Breast Cancer Cells ◽  
Migration And Invasion ◽  
Breast Cancer Cell Lines

AbstractThe role of organic anion transporting polypeptide 1B3 (SLCO1B3) in breast cancer is still controversial. The clinical immunohistochemical results showed that a greater proportion of patients with negative lymph nodes, AJCC stage I, and histological grade 1 (P < 0.05) was positively correlated with stronger expression of SLCO1B3, and DFS and OS were also increased significantly in these patients (P = 0.041, P = 0.001). Further subgroup analysis showed that DFS and OS were significantly enhanced with the increased expression of SLCO1B3 in the ER positive subgroup. The cellular function assay showed that the ability of cell proliferation, migration and invasion was significantly enhanced after knockdown of SLCO1B3 expression in breast cancer cell lines. In contrast, the ability of cell proliferation, migration and invasion was significantly reduced after overexpress the SLCO1B3 in breast cancer cell lines (P < 0.05). Overexpression or knockdown of SLCO1B3 had no effect on the apoptotic ability of breast cancer cells. High level of SLCO1B3 expression can inhibit the proliferation, invasion and migration of breast cancer cells, leading to better prognosis of patients. The role of SLCO1B3 in breast cancer may be related to estrogen. SLCO1B3 will become a potential biomarker for breast cancer diagnosis and prognosis assessment.

scholarly journals MicroRNA in combination with HER2-targeting drugs reduces breast cancer cell viability in vitro

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Lisa Svartdal Normann ◽  
Miriam Ragle Aure ◽  
Suvi-Katri Leivonen ◽  
Mads Haugland Haugen ◽  
Vesa Hongisto ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cancer Cells ◽  
Cell Lines ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Breast Cancer Cells ◽  
Targeted Treatment ◽  
Breast Cancer Cell Lines ◽  
Altered Expression ◽  
Her2 Breast Cancer

AbstractHER2-positive (HER2 +) breast cancer patients that do not respond to targeted treatment have a poor prognosis. The effects of targeted treatment on endogenous microRNA (miRNA) expression levels are unclear. We report that responsive HER2 + breast cancer cell lines had a higher number of miRNAs with altered expression after treatment with trastuzumab and lapatinib compared to poorly responsive cell lines. To evaluate whether miRNAs can sensitize HER2 + cells to treatment, we performed a high-throughput screen of 1626 miRNA mimics and inhibitors in combination with trastuzumab and lapatinib in HER2 + breast cancer cells. We identified eight miRNA mimics sensitizing cells to targeted treatment, miR-101-5p, mir-518a-5p, miR-19b-2-5p, miR-1237-3p, miR-29a-3p, miR-29c-3p, miR-106a-5p, and miR-744-3p. A higher expression of miR-101-5p predicted better prognosis in patients with HER2 + breast cancer (OS: p = 0.039; BCSS: p = 0.012), supporting the tumor-suppressing role of this miRNA. In conclusion, we have identified miRNAs that sensitize HER2 + breast cancer cells to targeted therapy. This indicates the potential of combining targeted drugs with miRNAs to improve current treatments for HER2 + breast cancers.

scholarly journals miR-342-5p as a Potential Regulator of HER2 Breast Cancer Cell Growth

MicroRNA ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 155-165 ◽  
Author(s):  
Evita Maria Lindholm ◽  
Suvi-Katri Leivonen ◽  
Eldri Undlien ◽  
Daniel Nebdal ◽  
Anna Git ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Lines ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Molecular Mechanisms ◽  
Target Genes ◽  
Breast Cancer Cell Lines ◽  
Nucleotide Exchange ◽  
Her2 Positive ◽  
Her2 Breast Cancer

Background: HER2 positive Breast Cancers (BC) have aggressive behavior and poor prognosis. Previously, we have identified miR-342-5p as an upstream regulator of HER2 signaling, as well as inhibitor of HER2 positive BC cell line growth. Objective: Here, we aimed to further investigate the molecular mechanisms behind miR-342-5pinduced HER2 pathway deregulation. </P><P> Method: Two HER2 amplified breast cancer cell lines were transiently transfected with miR-342-5p mimic or negative control, and gene expression was analyzed by Agilent microarrays. Three clinical datasets with BC patients were used to identify correlations between candidate genes and miR-342- 5p, and associations with survival. Results: Pathway analyses of all deregulated genes revealed a significant suppression of the HER2 downstream pathways ERK/MAPK and SAPK/JNK, whereas the miR-342-5p predicted target genes were enriched for pathways associated with cell motility.Biological functions linked to mitochondrial stability were ranked among the top toxicological functions in both gene lists. Among the most deregulated genes, Cytochrome B5 Reductase 3 (CYB5R3) and Rap Guanine Nucleotide Exchange Factor 6 (RAPGEF6) significantly anticorrelated and correlated, respectively, with miR-342-5p in all three clinical BC datasets. Low CYB5R3 levels and high RAPGEF6 levels were significantly associated with survival, although this was not directly associated with HER2 expression. Conclusion: Our data suggest that miR-342-5p overexpression in HER2 positive BC cell lines elicits broad effects on HER2 downstream signaling, cell motility and mitochondrial stability. Together these effects may render cells less proliferative and more sensitive to cellular stress.

scholarly journals Sodium-Dependent Glucose Transporter 1 (SGLT1) Stabled by HER2 Promotes Breast Cancer Cell Proliferation by Activation of the PI3K/Akt/mTOR Signaling Pathway in HER2+ Breast Cancer

2020 ◽  
Vol 2020 ◽  
pp. 1-12
Author(s):  
Jinlu Wang ◽  
Hongfei Ji ◽  
Xingjian Niu ◽  
Lei Yin ◽  
Yiran Wang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Proliferation ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Mtor Signaling ◽  
Her2 Status ◽  
Cancer Cell Proliferation ◽  
Breast Cancer Patients ◽  
Breast Cancer Cell Proliferation ◽  
Her2 Breast Cancer

Aerobic glycolysis is a hallmark of tumor cells. SGLT1 plays a vital role in glucose metabolism. However, whether SGLT1 could promote cell growth and proliferation in breast cancer remains unclear. Here, we investigated the expression of SGLT1 in breast cancer and examined its role in malignant behavior and prognosis. Further, we examined the SGLT1 expression in breast cancer tissues and its relationship with clinicopathologic characteristics. We clarified that SGLT1 was overexpressed in HER2+ breast cancer cell lines and was affected by HER2 status. We further found that SGLT1 affected breast cancer cell proliferation and patient survival by mediating cell survival pathway activation. SGLT1 was overexpressed in HER2+ breast cancers and associated with lymph node metastasis and HER2+ status. Inhibition of HER2 decreased SGLT1 expression, and the extracellular acidification rate was also reduced in the UACC812 and SKBR3 cell lines. These changes could be reversed by proteasome inhibitor treatment. Knockdown of SGLT1 blocked PI3K/Akt/mTOR signaling, thereby inhibiting cell proliferation. Further, we demonstrated that high SGLT1 was significantly correlated with shorter survival in all breast cancer patients and specifically in HER2+ breast cancer patients. Therefore, we conclude that SGLT1 is overexpressed in HER2+ breast cancer, thereby promoting cell proliferation and shortening survival by activating PI3K/Akt/mTOR signaling. This study submits that SGLT1 is promising not only as a novel biomarker of HER2+ breast cancer subtype but also as a potential drug target.

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