scholarly journals High Sensitivity of Circulating Tumor Cells Derived from a Colorectal Cancer Patient for Dual Inhibition with AKT and mTOR Inhibitors

Cells ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 2129
Author(s):  
Daniel J. Smit ◽  
Laure Cayrefourcq ◽  
Marie-Therese Haider ◽  
Nico Hinz ◽  
Klaus Pantel ◽  
...  

Circulating tumor cells (CTCs) are cells shed from the primary tumor into the bloodstream. While many studies on solid tumor cells exist, data on CTCs are scarce. The mortality of cancer is mostly associated with metastasis and recent research identified CTCs as initiators of metastasis. The PI3K/AKT/mTOR signaling pathway is an intracellular pathway that regulates essential functions including protein biosynthesis, cell growth, cell cycle control, survival and migration. Importantly, activating oncogenic mutations and amplifications in this pathway are frequently observed in a wide variety of cancer entities, underlining the significance of this signaling pathway. In this study, we analyzed the functional role of the PI3K/AKT/mTOR signaling pathway in the CTC-MCC-41 line, derived from a patient with metastatic colorectal cancer. One striking finding in our study was the strong sensitivity of this CTC line against AKT inhibition using MK2206 and mTOR inhibition using RAD001 within the nanomolar range. This suggests that therapies targeting AKT and mTOR could have been beneficial for the patient from which the CTC line was isolated. Additionally, a dual targeting approach of AKT/mTOR inside the PI3K/AKT/mTOR signaling pathway in the colorectal CTCs showed synergistic effects in vitro. Depending on the phenotypical behavior of CTC-MCC-41 in cell culture (adherent vs. suspension), we identified altered phosphorylation levels inside the PI3K/AKT/mTOR pathway. We observed a downregulation of the PI3K/AKT/mTOR signaling pathway, but not of the RAS/RAF/MAPK pathway, in CTCs growing in suspension in comparison to adherent CTCs. Our results highlight distinct functions of AKT isoforms in CTC-MCC-41 cells with respect to cell proliferation. Knockdown of AKT1 and AKT2 leads to significantly impaired proliferation of CTC-MCC-41 cells in vitro. Therefore, our data demonstrate that the PI3K/AKT/mTOR signaling pathway plays a key role in the proliferation of CTC-MCC-41.

2020 ◽  
Vol 27 ◽  
Author(s):  
Naser-Aldin Lashgari ◽  
Nazanin Momeni Roudsari ◽  
Saeideh Momtaz ◽  
Negar Ghanaatian ◽  
Parichehr Kohansal ◽  
...  

: Inflammatory bowel disease (IBD) is a general term for a group of chronic and progressive disorders. Several cellular and biomolecular pathways are implicated in the pathogenesis of IBD, yet the etiology is unclear. Activation of the mammalian target of rapamycin (mTOR) pathway in the intestinal epithelial cells was also shown to induce inflammation. This review focuses on the inhibition of the mTOR signaling pathway and its potential application in treating IBD. We also provide an overview on plant-derived compounds that are beneficial for the IBD management through modulation of the mTOR pathway. Data were extracted from clinical, in vitro and in vivo studies published in English between 1995 and May 2019, which were collected from PubMed, Google Scholar, Scopus and Cochrane library databases. Results of various studies implied that inhibition of the mTOR signaling pathway downregulates the inflammatory processes and cytokines involved in IBD. In this context, a number of natural products might reverse the pathological features of the disease. Furthermore, mTOR provides a novel drug target for IBD. Comprehensive clinical studies are required to confirm the efficacy of mTOR inhibitors in treating IBD.


2021 ◽  
Vol 20 ◽  
pp. 153303382199007
Author(s):  
Wenlin Liu ◽  
Jiandong Zhan ◽  
Rong Zhong ◽  
Rui Li ◽  
Xiaoli Sheng ◽  
...  

Background: Laryngeal cancer is one of the most common malignant tumors among head and neck cancers. Accumulating studies have indicated that long noncoding RNAs (lncRNAs) play an important role in laryngeal cancer occurrence and progression, however, the functional roles and relative regulatory mechanisms of lncRNA growth arrest-specific transcript 5 (GAS5) in laryngeal cancer progression remain unclear. Methods: The expression of lncRNA GAS5 in both laryngeal cancer tissues and cell lines was evaluated using quantitative reverse transcription-polymerase chain reaction (RT-qPCR) assay. The relationships between lncRNA GAS5 expression and clinical parameters were also analyzed. To determine the biological function of lncRNA GAS5, a lncRNA GAS5-specific plasmid was first transfected into laryngeal cancer cells using lentiviral technology. Cell counting kit-8 assay, flow cytometry, and Transwell assays were used to detect in vitro cell proliferation, apoptosis, cycle distribution, and metastasis abilities, respectively. Furthermore, in vivo cell growth experiments were also performed using nude mice. Additionally, western blotting was performed to identify the underlying regulatory mechanism. Results: In the current study, lncRNA GAS5 was downregulated in laryngeal cancer tissues and its low expression was closely associated with poor tumor differentiation, advanced TNM stage, lymph node metastasis, and shorter overall survival time. In addition, lncRNA GAS5 upregulation significantly inhibited laryngeal cancer cell proliferation both in vitro and in vivo. Moreover, in response to lncRNA GAS5 overexpression, more laryngeal cancer cells were arrested at the G2/M stage, accompanied by increased cell apoptosis rates and suppressed migration and invasion capacities. Mechanistically, our data showed that the overexpression of lncRNA GAS5 significantly regulated the PI3K/AKT/mTOR signaling pathway. Conclusion: LncRNA GAS5 might act as a suppressor gene during laryngeal cancer development, as it suppressed cell proliferation and metastasis by regulating the PI3K/AKT/mTOR signaling pathway; thus, lncRNA GAS5 is a promising therapeutic biomarker for the treatment of laryngeal cancer.


2021 ◽  
Vol 36 (Supplement_1) ◽  
Author(s):  
Zhenjian Xu ◽  
Junzhe Chen ◽  
Anping Xu

Abstract Background and Aims Our previous study found a new regulatory T cell subpopulation, CD4+CD126lowFoxp3+ regulatory T cells (CD4+CD126lowFoxp3+ Treg). This cell can maintain a stable immune regulatory function in the inflammatory state. Through in vivo and in vitro experiments, we have confirmed that CD4+CD126lowFoxp3+ Treg has an immunotherapeutic effect on T cell-mediated mouse models of autoimmune diseases such as colitis and collagen-induced arthritis (CIA). Further experimental studies showed that CD4+CD126lowFoxp3+ Treg could reduce the kidney injury caused by autoantibodies and prolong the survival time of lupus mice. However, the mechanism of CD4+CD126lowFoxp3+ Treg immunotherapy in lupus nephritis is not clear. The purpose of this study was to explore the mechanism of CD4+CD126lowFoxp3+ Treg immunotherapy in mice with lupus nephritis. Method In vitro experiments CD4+CD126lowFoxp3+ Treg or CD4+CD126lowFoxp3+ Treg pretreated with PD-1 inhibitor were co-cultured with T or B lymphocytes of lupus mice under different in vitro culture condition. The expression levels of Akt and mTOR of Treg in each group were measured under immunoinflammatory conditions. To observe the effects and differences of Treg groups on the activation, proliferation and differentiation of T or B cells and other immunomodulatory effects. In vivo experiments CD4+CD126lowFoxp3+ Treg (2 × 106/mouse) and CD4+CD126lowFoxp3+ Treg (2 × 106/mouse) pretreated with PD-1 inhibitor and PBS were injected into NZM2328 lupus mice, respectively. After cell injection, urine protein was measured weekly. Autoantibody expression in lupus mice was measured every two weeks. The effects of Treg on the proliferation and differentiation of T/B cells in lupus mice were observed. The therapeutic effects of Treg on lupus mice were observed. Results Compared with CD4+CD126lowFoxp3+ Treg, the expression of Akt and mTOR increases in PD-1 inhibitors pretreatment cells. The activation, proliferation and differentiation functions of T or B lymphocytes of lupus mice were significantly weakened by immunosuppression of PD-1 inhibitors pretreated Treg in vitro, indicating that CD4+CD126lowFoxp3+ Treg may inhibit Akt-mTOR signaling pathway through PD-1 in in vitro. Compared with CD4+CD126lowFoxp3+ Treg, the activation, proliferation and differentiation functions of T or B lymphocytes of lupus mice were significantly weakened by immunosuppression of PD-1 inhibitors pretreated Treg in vivo. And its therapeutic effect on lupus mice was ineffective, indicating that CD4+CD126lowFoxp3+ Treg may inhibit Akt-MTOR signaling pathway through PD-1 in vivo. Conclusion CD4+CD126lowFoxp3+ Treg may inhibit the Akt-mTOR signaling pathway by expressing PD-1, and maintain stable immunomodulatory function in the inflammatory state, thus producing immunotherapeutic effect on lupus nephritis mice.


Marine Drugs ◽  
2018 ◽  
Vol 16 (9) ◽  
pp. 325 ◽  
Author(s):  
Xiaojuan Li ◽  
Yunping Tang ◽  
Fangmiao Yu ◽  
Yu Sun ◽  
Fangfang Huang ◽  
...  

We investigated the antitumor mechanism of Anthopleura anjunae oligopeptide (AAP-H, YVPGP) in prostate cancer DU-145 cells in vitro and in vivo. Results indicated that AAP-H was nontoxic and exhibited antitumor activities. Cell cycle analysis indicated that AAP-H may arrest DU-145 cells in the S phase. The role of the phosphatidylinositol 3-kinase/protein kinase B/mammalian rapamycin target protein (PI3K/AKT/mTOR) signaling pathway in the antitumor mechanism of APP-H was investigated. Results showed that AAP-H treatment led to dose-dependent reduction in the levels of p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448), whereas t-AKT and t-PI3K levels remained unaltered compared to the untreated DU-145 cells. Inhibition of PI3K/AKT/mTOR signaling pathway in the DU-145 cells by employing inhibitor LY294002 (10 μM) or rapamycin (20 nM) effectively attenuated AAP-H-induced phosphorylation of AKT and mTOR. At the same time, inhibitor addition further elevated AAP-H-induced cleaved-caspase-3 levels. Furthermore, the effect of AAP-H on tumor growth and the role of the PI3K/AKT/mTOR signaling pathway in nude mouse model were also investigated. Immunohistochemical analysis showed that activated AKT, PI3K, and mTOR levels were reduced in DU-145 xenografts. Western blotting showed that AAP-H treatment resulted in dose-dependent reduction in p-AKT (Ser473), p-PI3K (p85), and p-mTOR (Ser2448) levels, whereas t-AKT and t-PI3K levels remained unaltered. Similarly, Bcl-xL levels decreased, whereas that of Bax increased after AAP-H treatment. AAP-H also increased initiator (caspase 8 and 9) and executor caspase (caspase 3 and 7) levels. Therefore, the antitumor mechanism of APP-H on DU-145 cells may involve regulation of the PI3K/AKT/mTOR signaling pathway, which eventually promotes apoptosis via mitochondrial and death receptor pathways. Thus, the hydrophobic oligopeptide (YVPGP) can be developed as an adjuvant for the prevention or treatment of prostate cancer in the future.


2019 ◽  
Vol 132 (7) ◽  
pp. 805-810
Author(s):  
Jing-Wei Lyu ◽  
Xue-Bi Xu ◽  
Kun-Qian Ji ◽  
Na Zhang ◽  
Yuan Sun ◽  
...  

2020 ◽  
Vol 48 (8) ◽  
pp. 030006052094616 ◽  
Author(s):  
Xiaofei Li ◽  
Ruifang Tian ◽  
Lan Liu ◽  
Lihui Wang ◽  
Dong He ◽  
...  

Objective Radiotherapy plays an important role in the treatment of colorectal cancer (CRC). However, some patients benefit minimally from radiotherapy because of radioresistance. This study investigated the effects of andrographolide on radiosensitivity in HCT116 CRC cells and examined its mechanism of action. Methods Cell survival, proliferation, apoptosis, and migration were evaluated using MTT, colony formation, flow cytometry, and Transwell cell invasion assays, respectively. Glycolysis-related indicators were measured to examine cell glycolytic activity. The expression of related proteins was detected by western blotting. Results After andrographolide treatment, the expression of phosphoinositide 3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway-related proteins, glycolytic activity, and cell survival and invasion rates were decreased in HCT116 cells. Andrographolide plus irradiation increased apoptosis and decreased survival, invasion, and colony formation compared with the effects of irradiation alone. Conclusion Andrographolide enhanced radiosensitivity by downregulating glycolysis via inhibition of the PI3K-Akt-mTOR signaling pathway in HCT116 cells.


2014 ◽  
Vol 5 (5) ◽  
pp. e1247-e1247 ◽  
Author(s):  
L-J Yuan ◽  
J-D Li ◽  
L Zhang ◽  
J-H Wang ◽  
T Wan ◽  
...  

Abstract Previously, we found that sperm-associated antigen 5 (SPAG5) was upregulated in pelvic lymph node metastasis–positive cervical cancer. The aim of this study is to examine the role of SPAG5 in the proliferation and tumorigenicity of cervical cancer and its clinical significance in tumor progression. In our study, SPAG5 expression in cervical cancer patients was detected using quantitative real-time polymerase chain reaction, western blotting, and immunohistochemistry; cervical cancer cell function with downregulated SPAG5 in vitro was explored using tetrazolium assay, flow cytometry, and colony formation and Transwell assays. SPAG5 was upregulated in tumor tissue compared with paired adjacent noncancerous tissues; SPAG5 upregulation in tumor tissues indicated poor disease-free survival, which was also an independent prognostic indicator for cervical cancer patients. In vitro study demonstrated that SPAG5 downregulation inhibited cell proliferation and growth significantly by G2/M arrest and induction of apoptosis, and hindered cell migration and invasion. Under SPAG5 downregulation, the sensitivity of cervical cancer cells differed according to taxol dose, which correlated with mammalian target of rapamycin (mTOR) signaling pathway activity. In general, SPAG5 upregulation relates to poor prognosis in cervical cancer patients, and SPAG5 is a regulator of mTOR activity during taxol treatment in cervical cancer.


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