PTEN activity could be a predictive marker of trastuzumab efficacy in the treatment of ErbB2-overexpressing breast cancer

2006 ◽  
Vol 24 (18_suppl) ◽  
pp. 10026-10026
Author(s):  
T. Fujita ◽  
K. Kawasaki ◽  
D. Takabatake ◽  
H. Takahashi ◽  
Y. Ogasawara ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Signaling Pathway ◽  
Single Agent ◽  
Metastatic Breast ◽  
Akt Signaling ◽  
Pten Expression ◽  
Clinical Samples ◽  
Drug Resistant ◽  
Akt Signaling Pathway

10026 Background: Trastuzumab is the only HER2/neu-directed therapy for the treatment of patients with metastatic breast cancer. The efficacy of trastuzumab depends on the HER2/neu status of the tumor and the patient’s prior treatment, but even when patients are selected on the basis of HER2/neu gene amplification, the single-agent response rate ranges from 12 to 30% and few patients respond to trastuzumab monotherapy. Here we propose PTEN as a predictive biomarker for trastuzumab efficacy. Methods: Human breast cancer SKBR3 and drug-resistant SKBR3/R cells were analyzed, in vitro. Also we examined, retrospectively, clinical samples from patients who had been treated with trastuzumab for the metastatic disease and analyzed the relationship between trastuzumab efficacy and PTEN expression profile with immunihistochemistry. The PTEN expression level was scored semiquantitatively based on staining intensity and distribution using the immunoreactive score. Statistical analysis was performed using the two-tailed student’s t test, Fisher’s test and ANOVA. Results: The PI3K/Akt signaling pathway was observed to be highly active in the drug-resistant cells, and their level of PTEN was significanctly low compared with parental SKBR3 cells. Delivery of antisense PTEN duplex siRNA significantly decreased the trastuzumab chemosensitivity of parental SKBR3 cells, and marked activation of Akt signaling pathway was also recognized in oligonucleotid delivered parental cells. Moreover, in clinical analysis, immunohistochemical investigation revealed that trastuzumab treatment was remarkably successful in patients with elevated PTEN expression and statistically significant (p<0.05). Conclusions: PTEN activity might play an important and major role in its HER2/PI3K/Akt-mediated anti-tumor effect, and could be a useful biomarker for predicting the efficacy of trastuzumab in the treatment of breast cancer. No significant financial relationships to disclose.

scholarly journals Nobiletin enhances the development and quality of bovine embryos in vitro during two key periods of embryonic genome activation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Karina Cañón-Beltrán ◽  
Yulia N. Cajas ◽  
Serafín Peréz-Cerezales ◽  
Claudia L. V. Leal ◽  
Ekaitz Agirregoitia ◽  
...  
Keyword(s):  
Embryonic Development ◽  
Signaling Pathway ◽  
Akt Signaling ◽  
Mitochondrial Activity ◽  
Bovine Embryos ◽  
Akt Signaling Pathway ◽  
Cell Stage ◽  
Development In Vitro

AbstractIn vitro culture can alter the development and quality of bovine embryos. Therefore, we aimed to evaluate whether nobiletin supplementation during EGA improves embryonic development and blastocyst quality and if it affects PI3K/AKT signaling pathway. In vitro zygotes were cultured in SOF + 5% FCS (Control) or supplemented with 5, 10 or 25 µM nobiletin (Nob5, Nob10, Nob25) or with 0.03% dimethyl-sulfoxide (CDMSO) during minor (2 to 8-cell stage; MNEGA) or major (8 to 16-cell stage; MJEGA) EGA phase. Blastocyst yield on Day 8 was higher in Nob5 (42.7 ± 1.0%) and Nob10 (44.4 ± 1.3%) for MNEGA phase and in Nob10 (61.0 ± 0.8%) for MJEGA phase compared to other groups. Mitochondrial activity was higher and lipid content was reduced in blastocysts produced with nobiletin, irrespective of EGA phase. The mRNA abundance of CDK2, H3-3B, H3-3A, GPX1, NFE2L2 and PPARα transcripts was increased in 8-cells, 16-cells and blastocysts from nobiletin groups. Immunofluorescence analysis revealed immunoreactive proteins for p-AKT forms (Thr308 and Ser473) in bovine blastocysts produced with nobiletin. In conclusion, nobiletin supplementation during EGA has a positive effect on preimplantation bovine embryonic development in vitro and corroborates on the quality improvement of the produced blastocysts which could be modulated by the activation of AKT signaling pathway.

The phosphatidyl inositol 3-kinase/AKT signaling pathway in breast cancer

2010 ◽  
Vol 29 (4) ◽  
pp. 751-759 ◽  
Author(s):  
Carlos A. Castaneda ◽  
Hernán Cortes-Funes ◽  
Henry L. Gomez ◽  
Eva M. Ciruelos
Keyword(s):  
Breast Cancer ◽  
Signaling Pathway ◽  
Phosphatidyl Inositol ◽  
Akt Signaling ◽  
Akt Signaling Pathway

Capn4 aggravates angiotensin II-induced cardiac hypertrophy by activating the IGF-AKT signaling pathway

2021 ◽  
Author(s):  
Yuanping Cao ◽  
Qun Wang ◽  
Caiyun Liu ◽  
Wenjun Wang ◽  
Songqing Lai ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Signaling Pathway ◽  
Expression Patterns ◽  
Akt Signaling ◽  
Calpain Inhibitor ◽  
Ang Ii ◽  
Akt Signaling Pathway ◽  
Calpain Activity

Abstract Capn4 belongs to a family of calpains that participate in a wide variety of biological functions, but little is known about the role of Capn4 in cardiac disease. Here, we show that the expression of Capn4 was significantly increased in Angiotensin II (Ang II)-treated cardiomyocytes and Ang II-induced cardiac hypertrophic mouse hearts. Importantly, in agreement with the Capn4 expression patterns, the maximal calpain activity measured in heart homogenates was elevated in Ang II-treated mice, and oral coadministration of SNJ-1945 (calpain inhibitor) attenuated the total calpain activity measured in vitro. Functional assays indicated that overexpression of Capn4 obviously aggravated Ang II-induced cardiac hypertrophy, whereas Capn4 knockdown resulted in the opposite phenotypes. Further investigation demonstrated that Capn4 maintained the activation of the insulin-like growth factor (IGF)-AKT signaling pathway in cardiomyocytes by increasing c-Jun expression. Mechanistic investigations revealed that Capn4 directly bound and stabilized c-Jun, and knockdown of Capn4 increased the ubiquitination level of c-Jun in cardiomyocytes. Additionally, our results demonstrated that the antihypertrophic effect of Capn4 silencing was partially dependent on the inhibition of c-Jun. Overall, these data suggested that Capn4 contributes to cardiac hypertrophy by enhancing the c-Jun-mediated IGF-AKT signaling pathway and could be a potential therapeutic target for hypertrophic cardiomyopathy.

A77 1726 (leflunomide) blocks and reverses cardiac hypertrophy and fibrosis in mice

2018 ◽  
Vol 132 (6) ◽  
pp. 685-699 ◽  
Author(s):  
Zhen-Guo Ma ◽  
Xin Zhang ◽  
Yu-Pei Yuan ◽  
Ya-Ge Jin ◽  
Ning Li ◽  
...  
Keyword(s):  
T Cell ◽  
Cardiac Hypertrophy ◽  
Protective Effect ◽  
Signaling Pathway ◽  
Cardiac Fibrosis ◽  
Pressure Overload ◽  
Akt Signaling ◽  
Akt Signaling Pathway

T-cell infiltration and the subsequent increased intracardial chronic inflammation play crucial roles in the development of cardiac hypertrophy and heart failure (HF). A77 1726, the active metabolite of leflunomide, has been reported to have powerful anti-inflammatory and T cell-inhibiting properties. However, the effect of A77 1726 on cardiac hypertrophy remains completely unknown. Herein, we found that A77 1726 treatment attenuated pressure overload or angiotensin II (Ang II)-induced cardiac hypertrophy in vivo, as well as agonist-induced hypertrophic response of cardiomyocytes in vitro. In addition, we showed that A77 1726 administration prevented induction of cardiac fibrosis by inhibiting cardiac fibroblast (CF) transformation into myofibroblast. Surprisingly, we found that the protective effect of A77 1726 was not dependent on its T lymphocyte-inhibiting property. A77 1726 suppressed the activation of protein kinase B (AKT) signaling pathway, and overexpression of constitutively active AKT completely abolished A77 1726-mediated cardioprotective effects in vivo and in vitro. Pretreatment with siRNA targetting Fyn (si Fyn) blunted the protective effect elicited by A77 1726 in vitro. More importantly, A77 1726 was capable of blocking pre-established cardiac hypertrophy in mice. In conclusion, A77 1726 attenuated cardiac hypertrophy and cardiac fibrosis via inhibiting FYN/AKT signaling pathway.

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