1
|
Meuten TK, Dean GA, Thamm DH. Review: The PI3K-AKT-mTOR signal transduction pathway in canine cancer. Vet Pathol 2024; 61:339-356. [PMID: 37905509 DOI: 10.1177/03009858231207021] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2023]
Abstract
Tumors in dogs and humans share many similar molecular and genetic features, incentivizing a better understanding of canine neoplasms not only for the purpose of treating companion animals, but also to facilitate research of spontaneously developing tumors with similar biologic behavior and treatment approaches in an immunologically competent animal model. Multiple tumor types of both species have similar dysregulation of signal transduction through phosphatidylinositol 3-kinase (PI3K), protein kinase B (PKB; AKT), and mechanistic target of rapamycin (mTOR), collectively known as the PI3K-AKT-mTOR pathway. This review aims to delineate the pertinent aspects of the PI3K-AKT-mTOR signaling pathway in health and in tumor development. It will then present a synopsis of current understanding of PI3K-AKT-mTOR signaling in important canine cancers and advancements in targeted inhibitors of this pathway.
Collapse
|
2
|
Michishita M, Ochiai K, Nakahira R, Azakami D, Machida Y, Nagashima T, Nakagawa T, Ishiwata T. mTOR pathway as a potential therapeutic target for cancer stem cells in canine mammary carcinoma. Front Oncol 2023; 13:1100602. [PMID: 36816969 PMCID: PMC9931192 DOI: 10.3389/fonc.2023.1100602] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 01/16/2023] [Indexed: 02/05/2023] Open
Abstract
Mammary adenocarcinoma, the most common cancer in female dogs, often exhibits the lymph node and lung metastases and has a higher mortality rate. However, mammary adenocarcinoma has no established treatment, except early surgical excision. Canine mammary carcinoma has many common features with human mammary carcinoma, including clinical characteristics, heterogeneity, and genetic aberrations, making it an excellent spontaneous tumor model for human breast cancer. Diverse cancers comprised heterogeneous cell populations originating from cancer stem cells (CSCs) with self-renewal ability. Therefore, in addition to conventional therapy, therapeutic strategies targeting CSCs are essential for cancer eradication. The present study aimed to extract inhibitors of canine mammary CSCs that suppress their self-renewal ability. Sphere-formation assay, which evaluates self-renewal ability, was performed for the canine mammary cancer cell lines CTBp and CNMp. The spheres formed in this assay were used in inhibitor library screening, which identified various signaling pathways such as proteosome, stress inducer, and mammalian target of rapamycin (mTOR). The present study focused on the mTOR signaling pathway. Western blotting showed higher levels of phosphorylated mTOR in sphere-forming CTBp and CNMp cells than in adherent cells. Drug sensitivity examination using the mTOR inhibitors everolimus and temsirolimus revealed dose-dependent reductions in viability among both sphere-forming cells and adherent cells. Expression of phosphorylated mTOR in adherent and sphere-forming cells decreased by everolimus and temsirolimus treatment. In mice transplanted with CTBp-derived spheres, everolimus treatment significantly decreased tumor volume compared to control. These results reveal that the mTOR signaling pathway may be a potential to be a therapeutic target in both cancer cells and CSCs. Novel therapeutic strategies for canine mammary carcinoma are expected to benefit to human breast carcinoma as well.
Collapse
Affiliation(s)
- Masaki Michishita
- Department of Veterinary Pathology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Tokyo, Japan,Research Center for Animal Life Science, Nippon Veterinary and Life Science University, Tokyo, Japan,*Correspondence: Masaki Michishita,
| | - Kazuhiko Ochiai
- Research Center for Animal Life Science, Nippon Veterinary and Life Science University, Tokyo, Japan,Department of Veterinary Hygiene, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Tokyo, Japan
| | - Rei Nakahira
- Department of Veterinary Pathology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Tokyo, Japan
| | - Daigo Azakami
- Laboratory of Veterinary Clinical Oncology, Faculty of Agriculture, Tokyo University of Agriculture and Technology, Tokyo, Japan
| | - Yukino Machida
- Department of Veterinary Pathology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Tokyo, Japan
| | - Tomokazu Nagashima
- Department of Veterinary Pathology, Faculty of Veterinary Science, Nippon Veterinary and Life Science University, Tokyo, Japan
| | - Takayuki Nakagawa
- Laboratory of Veterinary Surgery, Graduate School of Agricultural and Life Science, The University of Tokyo, Tokyo, Japan
| | - Toshiyuki Ishiwata
- Division of Aging and Carcinogenesis, Research Team for Geriatric Pathology, Tokyo Metropolitan Institute of Gerontology, Tokyo, Japan
| |
Collapse
|
3
|
Delgado L, Brilhante-simões P, Garcez F, Monteiro L, Pires I, Prada J. p-S6 as a Prognostic Biomarker in Canine Oral Squamous Cell Carcinoma. Biomolecules 2022; 12:935. [PMID: 35883491 PMCID: PMC9313205 DOI: 10.3390/biom12070935] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 06/25/2022] [Accepted: 06/28/2022] [Indexed: 12/03/2022] Open
Abstract
Scarce information exists on the role of mTOR pathway proteins and their association to aggressiveness and prognosis of patients with canine oral cancers. We aimed to investigate the activated form of mTOR and its downstream S6 protein in canine oral squamous cell carcinoma (OSCC), and to evaluate potential associations between protein expression and clinic-pathologic variables and survival. For that we analysed p-mTOR and p-S6 protein expression by immunohistochemistry in 61 canine OSCCs. Multivariate analysis was conducted to examine their role in patients’ cancer-specific survival (CSS). p-mTOR and p-S6 expression were present in almost all cases. High-expression of p-mTOR was observed in 44 (72.1%) cases using extent score and 52 (85.2%) cases using intensity score. For p-S6, high expression was observed in 53 (86.9%) cases using extent score and in 54 (88.5%) cases using intensity score. An independent prognostic value for p-S6 extension (p = 0.027), tumour stage (p = 0.013) and treatment (p = 0.0009) was found in patients’ CSS analysis. Our data suggest that p-mTOR and p-S6 proteins are commonly expressed in canine OSCC and p-S6 expression is correlated with poor CSS in dogs with OSCC. More studies should be performed to identify possible therapeutic targets related with mTOR pathway for these patients.
Collapse
|
4
|
Murase Y, Hosoya K, Sato T, Kim S, Okumura M. Antitumor activity of the dual PI3K/mTOR inhibitor gedatolisib and the involvement of ABCB1 in gedatolisib resistance in canine tumor cells. Oncol Rep 2022; 47:61. [PMID: 35088890 PMCID: PMC8848474 DOI: 10.3892/or.2022.8272] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 02/25/2021] [Indexed: 11/15/2022] Open
Abstract
The phosphatidylinositol 3-kinase/mammalian target of rapamycin (PI3K/mTOR) signaling pathway is a therapeutic target for various types of human tumors, and dual PI3K/mTOR inhibitors demonstrate antitumor activities in both preclinical and clinical studies. However, resistance mechanisms limit their abilities. As the molecular mechanisms involved in the cellular resistance are not clear in any canine tumors, an understanding of resistance mechanisms would support the potential use of dual PI3K/mTOR inhibitors in canine tumors. The antitumor activity of gedatolisib on cell viability, protein phosphorylation, and cell cycle distribution was assessed using 12 canine tumor cell lines from 6 types of tumors. In addition, the molecular determinants involved in the cellular sensitivity to gedatolisib were explored by investigating the involvement of serum-and-glucocorticoid-induced kinase 1 (SGK1), PIK3CA, and ATP-binding cassette, subfamily B, member 1 (ABCB1). The results demonstrated that gedatolisib decreased cell viability in all cell lines, with IC50 values <1 µM in 10 of the 12 lines. Gedatolisib inhibited Akt and mTOR complex 1 substrate phosphorylation and induced G0/G1 cell cycle arrest. However, certain cell lines with higher IC50 values were more resistant to these effects. These cell lines exhibited higher ABCB1 activity and the ABCB1 inhibitor cyclosporin A enhanced the decrease of cell viability caused by gedatolisib. SGK1 overexpression did not confer resistance to gedatolisib. The mutations of E545K and H1047R in PIK3CA were not observed. The present results indicated that gedatolisib decreased cell viability in canine tumor cell lines and ABCB1 played an important role in gedatolisib resistance, supporting the potential use of gedatolisib for canine tumors.
Collapse
Affiliation(s)
- Yusuke Murase
- Laboratory of Veterinary Surgery, Department of Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060‑0818, Japan
| | - Kenji Hosoya
- Laboratory of Veterinary Surgery, Department of Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060‑0818, Japan
| | - Takachika Sato
- Laboratory of Veterinary Surgery, Department of Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060‑0818, Japan
| | - Sangho Kim
- Laboratory of Veterinary Surgery, Department of Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060‑0818, Japan
| | - Masahiro Okumura
- Laboratory of Veterinary Surgery, Department of Clinical Sciences, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Hokkaido 060‑0818, Japan
| |
Collapse
|
5
|
Fan Y, Ren X, Wang Y, Xu E, Wang S, Ge R, Liu Y. Metformin inhibits the proliferation of canine mammary gland tumor cells through the AMPK/AKT/mTOR signaling pathway in vitro. Oncol Lett 2021; 22:852. [PMID: 34733370 PMCID: PMC8561621 DOI: 10.3892/ol.2021.13113] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2020] [Accepted: 06/14/2021] [Indexed: 11/25/2022] Open
Abstract
As an anti-diabetic drug, metformin has been demonstrated to exhibit antitumor effects. However, the mechanisms involved in decreasing tumor formation, including canine mammary gland tumors (CMGTs), are not well elucidated. The aim of the present study was to evaluate the ability of metformin to induce apoptosis and cell cycle arrest in CMGT cells, as well as identifying the pathways underlying these effects. Cell viability was assessed by Cell Counting Kit-8 analysis following treating with metformin. Subsequently, apoptosis and cell cycle progression were assessed by flow cytometry, and the expression of associated proteins was examined. Expression levels of classical AMP-activated protein kinase (AMPK), protein kinase B (AKT), mechanistic target of rapamycin (mTOR) and eukaryotic translation initiation factor 4E-binding protein 1 (4E-BP1) were then investigated using western blot analysis. Metformin inhibited the proliferation of CHMm cells in a concentration-dependent manner. Specifically, metformin induced cell cycle arrest in the G0/G1 phases, accompanied by increased expression of p21 and p27, and decreased expression of cyclin D1 and cyclin-dependent kinase 4. Marked levels of apoptosis were observed in CHMm cells alongside the activation of caspase-3 and cleavage of poly(ADP-ribose) polymerase. Also, the level of Bcl-2 was decreased, and that of Bax was increased. The expression of associated signaling molecules revealed that metformin markedly increased the phosphorylation of AMPK in CHMm cells, and decreased the levels of phosphorylated (p-)AKT, p-mTOR and p-4E-BP1, while Compound C reversed these changes. These findings demonstrated that metformin may be a potential therapeutic agent for CMGTs, acting via the AMPK/AKT/mTOR signaling pathway.
Collapse
Affiliation(s)
- Yuying Fan
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150000, P.R. China
| | - Xiaoli Ren
- College of Veterinary Medicine, Henan University of Animal Husbandry and Economy, Zhengzhou, Henan 450046, P.R. China
| | - Yingxue Wang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150000, P.R. China
| | - Enshuang Xu
- College of Animal Science and Veterinary Medicine, Heilongjiang Bayi Agricultural University, Daqing, Heilongjiang 163000, P.R. China
| | - Shuang Wang
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150000, P.R. China
| | - Ruidong Ge
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150000, P.R. China
| | - Yun Liu
- Department of Clinical Veterinary Medicine, College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150000, P.R. China
| |
Collapse
|
6
|
Mathew R, Sajitha IS, Balakrishnan-Nair DK, Nair SS, Kariyil BJ, Abraham MJ. Histological and Immunohistochemical Evaluation of Phosphorylated Mechanistic Target of Rapamycin in Canine Skin Tumours. J Comp Pathol 2021; 184:60-64. [PMID: 33894879 DOI: 10.1016/j.jcpa.2021.02.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 12/11/2020] [Accepted: 02/05/2021] [Indexed: 10/21/2022]
Abstract
The mechanistic target of rapamycin (mTOR) plays an important role in cellular functions, including growth and metabolism. Recently, mTOR and the activated phosphorylated form of mTOR (p-mTOR) have been reported as potential prognostic markers in many human tumours. However, there are few studies on its activation in canine tumours. We investigated the expression of p-mTOR in 17 canine skin tumours (CSTs), of which 58.8% were epithelial and melanocytic and 41.2% were mesenchymal tumours. Seventy-six per cent of the CSTs had high or moderate expression of p-mTOR. Mean p-mTOR expression in the epithelial and melanocytic tumours (5.7 ± 0.56) was significantly higher (P <0.05) than that of the mesenchymal tumours (3.14 ± 0.55). The age of the animals had no influence on p-mTOR expression. These findings suggest that activation of m-TOR is important in the development of skin tumours in dogs and the study might form the basis for further research on utilizing m-TOR inhibitors as improved therapeutic modalities in canine skin tumours.
Collapse
Affiliation(s)
- Raimon Mathew
- Department of Veterinary Pathology, College of Veterinary and Animal Sciences, Mannuthy, Kerala, India.
| | - Indira S Sajitha
- Department of Veterinary Pathology, College of Veterinary and Animal Sciences, Mannuthy, Kerala, India
| | | | - Sudheesh S Nair
- Department of Veterinary Surgery & Radiology, College of Veterinary and Animal Sciences, Mannuthy, Kerala, India
| | - Bibu J Kariyil
- Department of Veterinary Pharmacology & Toxicology, College of Veterinary and Animal Sciences, Mannuthy, Kerala, India; Kerala Veterinary and Animal Sciences University, Wayanad, Kerala, India
| | - Mammen J Abraham
- Department of Veterinary Pathology, College of Veterinary and Animal Sciences, Mannuthy, Kerala, India
| |
Collapse
|
7
|
Rivera-Calderón LG, Fonseca-Alves CE, Kobayashi PE, Carvalho M, Vasconcelos RO, Laufer-Amorim R. p-mTOR, p-4EBP-1 and eIF4E expression in canine prostatic carcinoma. Res Vet Sci 2018; 122:86-92. [PMID: 30476726 DOI: 10.1016/j.rvsc.2018.11.006] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2018] [Revised: 09/03/2018] [Accepted: 11/11/2018] [Indexed: 01/14/2023]
Abstract
The mTOR/4E-BP1/eIF4E pathway plays important roles in the neoplastic transformation process and in tumour growth. In men, the mTOR/4E-BP1/eIF4E pathway was described as altered in different tumours, including prostate cancer (PC). Apart from humans, the dog is the only species that develops PC with high frequency and is considered a good model for comparative oncology initiatives. Due to limited information on this pathway in canine tumours, this study aimed to investigate mTOR, 4E-BP1 and eIF4E gene and protein expression in canine PC, as well as in metastatic and normal prostatic tissues, and to evaluate the correlations between gene/protein expression and Gleason score (GS) in PC. A total of 35 formalin-fixed paraffin-embedded (FFPE) samples, including 13 of normal prostatic tissue, 17 PC samples and 5 metastasis samples, were evaluated by immunohistochemistry and qPCR. mTOR gene mutation in the kinase domain was also investigated. We identified higher p-mTOR and eIF4E protein levels in canine PC with higher GS values (≥ 8) and a significant positive correlation in expression between these proteins. eIF4E overexpression was observed in metastasis relative to expression in normal samples. Our data suggest that p-mTOR and eIF4E expression is positively correlated with GS in canine PC, similar to the pattern in humans. More studies of the mTOR/4EBP1/eIF4E pathway should be performed to identify possible correlations of the proteins involved with clinical and pathologic findings in canine PC and the roles of these proteins as therapeutic targets for the treatment of canine PC.
Collapse
Affiliation(s)
- Luis G Rivera-Calderón
- Department of Veterinary Pathology, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Carlos E Fonseca-Alves
- Department of Veterinary Clinic, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil
| | - Priscila E Kobayashi
- Department of Veterinary Clinic, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil
| | - Márcio Carvalho
- Department of Veterinary Clinic, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil
| | - Rosemeri O Vasconcelos
- Department of Veterinary Pathology, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Jaboticabal, São Paulo, Brazil
| | - Renée Laufer-Amorim
- Department of Veterinary Clinic, School of Veterinary Medicine and Animal Science, São Paulo State University (Unesp), Botucatu, São Paulo, Brazil.
| |
Collapse
|