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Shi Y, Kang Q, Zhou H, Yue X, Bi Y, Luo Q. Aberrant LETM1 elevation dysregulates mitochondrial functions and energy metabolism and promotes lung metastasis in osteosarcoma. Genes Dis 2024; 11:100988. [PMID: 38292199 PMCID: PMC10825238 DOI: 10.1016/j.gendis.2023.05.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Revised: 04/10/2023] [Accepted: 05/25/2023] [Indexed: 02/01/2024] Open
Abstract
Osteosarcoma is a differentiation-deficient disease, and despite the unique advantages and great potential of differentiation therapy, there are only a few known differentiation inducers, and little research has been done on their targets. Cell differentiation is associated with an increase in mitochondrial content and activity. The metabolism of some tumor cells is characterized by impaired oxidative phosphorylation, as well as up-regulation of aerobic glycolysis and pentose phosphate pathways. Leucine-containing zipper and EF-hand transmembrane protein 1 (LETM1) is involved in the maintenance of mitochondrial morphology and is closely associated with tumorigenesis and progression, as well as cancer cell stemness. We found that MG63 and 143B osteosarcoma cells overexpress LETM1 and exhibit abnormalities in mitochondrial structure and function. Knockdown of LETM1 partially restored the mitochondrial structure and function, inhibited the pentose phosphate pathway, promoted oxidative phosphorylation, and led to osteogenic differentiation. It also inhibited spheroid cell formation, proliferation, migration, and invasion in an in vitro model. When LETM1 was knocked down in vivo, there was reduced tumor formation and lung metastasis. These data suggest that mitochondria are aberrant in LETM1-overexpressing osteosarcoma cells, and knockdown of LETM1 partially restores the mitochondrial structure and function, inhibits the pentose phosphate pathway, promotes oxidative phosphorylation, and increases osteogenic differentiation, thereby reducing malignant biological behavior of the cells.
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Affiliation(s)
- Yulu Shi
- Stem Cell Biology and Therapy Laboratory, The Children’s Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Quan Kang
- Department of Pediatric Surgery, The Children’s Hospital of Chongqing Medical University, Chongqing 400014, China
| | - Hong Zhou
- Stem Cell Biology and Therapy Laboratory, The Children’s Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Xiaohan Yue
- Stem Cell Biology and Therapy Laboratory, The Children’s Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Yang Bi
- Stem Cell Biology and Therapy Laboratory, The Children’s Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
| | - Qing Luo
- Stem Cell Biology and Therapy Laboratory, The Children’s Hospital of Chongqing Medical University, National Clinical Research Center for Child Health and Disorders, Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing Key Laboratory of Pediatrics, Chongqing 400014, China
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Ma Y, Jin J, Xue Z, Zhao J, Cai W, Zhang W. Integrated multi-omics analysis and machine learning developed a prognostic model based on mitochondrial function in a large multicenter cohort for Gastric Cancer. J Transl Med 2024; 22:381. [PMID: 38654380 PMCID: PMC11040813 DOI: 10.1186/s12967-024-05109-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Accepted: 03/18/2024] [Indexed: 04/25/2024] Open
Abstract
BACKGROUND Gastric cancer (GC) is a common and aggressive type of cancer worldwide. Despite recent advancements in its treatment, the prognosis for patients with GC remains poor. Understanding the mechanisms of cell death in GC, particularly those related to mitochondrial function, is crucial for its development and progression. However, more research is needed to investigate the significance of the interaction between mitochondrial function and GC cell death. METHODS We employed a robust computational framework to investigate the role of mitochondria-associated proteins in the progression of GC in a cohort of 1,199 GC patients. Ten machine learning algorithms were utilized and combined into 101 unique combinations. Ultimately, we developed a Mitochondrial-related-Score (MitoScore) using the machine learning model that exhibited the best performance. We observed the upregulation of LEMT2 and further explored its function in tumor progression. Mitochondrial functions were assessed by measuring mitochondrial ATP, mitochondrial membrane potential, and levels of lactate, pyruvate, and glucose. RESULTS MitoScore showed significant correlations with GC immune and metabolic functions. The higher MitoScore subgroup exhibited enriched metabolic pathways and higher immune activity. Overexpression of LETM2 (leucine zipper and EF-hand containing transmembrane protein 2) significantly enhanced tumor proliferation and metastasis. LETM2 plays a role in promoting GC cell proliferation by activating the mTOR pathway, maintaining mitochondrial homeostasis, and promoting glycolysis. CONCLUSION The powerful machine learning framework highlights the significant potential of MitoScore in providing valuable insights and accurate assessments for individuals with GC. This study also enhances our understanding of LETM2 as an oncogene signature in GC. LETM2 may promote tumor progression by maintaining mitochondrial health and activating glycolysis, offering potential targets for diagnosis, treatment, and prognosis of GC.
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Affiliation(s)
- Yimeng Ma
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jingjing Jin
- Department of Microbiology and Immunology, School of Basic Medical Sciences, Wenzhou Collaborative Innovation Center of Gastrointestinal Cancer in Basic Research and Precision Medicine, Wenzhou Key Laboratory of Cancer-Related Pathogens and Immunity, Wenzhou Medical University, Wenzhou, China
| | - Zixuan Xue
- Department of Clinical Laboratory, Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China
| | - Jungang Zhao
- Department of Urology, The Fourth Affiliated Hospital of Zhejiang University School of Medicine, Yiwu, 322000, China
| | - Weiyang Cai
- Department of Gastroenterology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
| | - Wanli Zhang
- Department of Neurology, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, Zhejiang, China.
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Lu L, Qi Z, Chen Z, Wang H, Wei X, Zhao B, Wang Z, Shao Y, Tu J, Song X. Avian pathogenic Escherichia coli T6SS effector protein Hcp2a causes mitochondrial dysfunction through interaction with LETM1 protein in DF-1 cells. Poult Sci 2024; 103:103514. [PMID: 38367471 PMCID: PMC10879833 DOI: 10.1016/j.psj.2024.103514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2023] [Revised: 01/25/2024] [Accepted: 01/25/2024] [Indexed: 02/19/2024] Open
Abstract
The type VI secretion system (T6SS) of avian pathogenic Escherichia coli (APEC) can affect the functions of eukaryotic cells by secreting or injecting effectors. Hemolysin co-regulatory protein (Hcp), one of the markers of the T6SS, is both a structural protein and an effector protein of the T6SS. According to previous studies, mitochondria in eukaryotic cells are targeted by pathogenic bacteria. However, little is known about the regulation of mitochondria in eukaryotic host cells by the T6SS effector protein Hcp of APEC. In our study, DF-1 cells co-incubated with Hcp2a protein for 6 h showed decreased mitochondrial membrane potential, increased Ca2+ concentration, and increased cellular reactive oxygen species (ROS) levels. We therefore conclude that Hcp2a protein causes dysfunction to mitochondria in DF-1 cells. To explain the mechanism that causes mitochondrial dysfunction, we reanalyzed the Hcp2a interaction protein dataset in DF-1 cells, and the Leucine zipper EF-hand-containing transmembrane protein 1 (LETM1), which is associated with mitochondria, was screened. The protein and molecular docking results showed that Hcp2a protein and LETM1 protein have better binding. Finally, subcellular localization results showed that Hcp2a was localized to mitochondria. In summary, Hcp2a effector proteins caused dysfunction to DF-1 cellular mitochondria, and we hypothesize that the interaction of Hcp2a protein with LETM1 protein induces mitochondrial dysfunction and promotes mitochondrial localization of Hcp2a in DF-1 cells.
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Affiliation(s)
- Liting Lu
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Zhao Qi
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Zhe Chen
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Haiyang Wang
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Xiyang Wei
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Bingyu Zhao
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Zhenyu Wang
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Ying Shao
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China
| | - Jian Tu
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Joint Research Center for Food Nutrition and Health of IHM, Anhui Agricultural University, Hefei, PR China
| | - Xiangjun Song
- Anhui Province Key Laboratory of Veterinary Pathobiology and Disease Control, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Anhui Province Engineering Laboratory for Animal Food Quality and Bio-Safety, College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, PR China; Joint Research Center for Food Nutrition and Health of IHM, Anhui Agricultural University, Hefei, PR China.
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Akinyemi AO, Simpson KE, Oyelere SF, Nur M, Ngule CM, Owoyemi BCD, Ayarick VA, Oyelami FF, Obaleye O, Esoe DP, Liu X, Li Z. Unveiling the dark side of glucose-regulated protein 78 (GRP78) in cancers and other human pathology: a systematic review. Mol Med 2023; 29:112. [PMID: 37605113 PMCID: PMC10464436 DOI: 10.1186/s10020-023-00706-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Accepted: 07/26/2023] [Indexed: 08/23/2023] Open
Abstract
Glucose-Regulated Protein 78 (GRP78) is a chaperone protein that is predominantly expressed in the lumen of the endoplasmic reticulum. GRP78 plays a crucial role in protein folding by assisting in the assembly of misfolded proteins. Under cellular stress conditions, GRP78 can translocate to the cell surface (csGRP78) were it interacts with different ligands to initiate various intracellular pathways. The expression of csGRP78 has been associated with tumor initiation and progression of multiple cancer types. This review provides a comprehensive analysis of the existing evidence on the roles of GRP78 in various types of cancer and other human pathology. Additionally, the review discusses the current understanding of the mechanisms underlying GRP78's involvement in tumorigenesis and cancer advancement. Furthermore, we highlight recent innovative approaches employed in downregulating GRP78 expression in cancers as a potential therapeutic target.
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Affiliation(s)
| | | | | | - Maria Nur
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, USA
| | | | | | | | - Felix Femi Oyelami
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, USA
| | | | - Dave-Preston Esoe
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, USA
| | - Xiaoqi Liu
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, USA
- Markey Cancer Center, College of Medicine, University of Kentucky, Lexington, USA
| | - Zhiguo Li
- Department of Toxicology and Cancer Biology, University of Kentucky, Lexington, USA.
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Wu H, Chen W, Chen Z, Li X, Wang M. Novel tumor therapy strategies targeting endoplasmic reticulum-mitochondria signal pathways. Ageing Res Rev 2023; 88:101951. [PMID: 37164161 DOI: 10.1016/j.arr.2023.101951] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 04/13/2023] [Accepted: 05/07/2023] [Indexed: 05/12/2023]
Abstract
Organelles form tight connections through membrane contact sites, thereby cooperating to regulate homeostasis and cell function. Among them, the contact between endoplasmic reticulum (ER), the main intracellular calcium storage organelles, and mitochondria has been recognized for decades, and its main roles in the ion and lipid transport, ROS signaling, membrane dynamic changes and cellular metabolism are basically determined. At present, many tumor chemotherapeutic drugs rely on ER-mitochondrial calcium signal to function, but the mechanism of targeting resident molecules at the mitochondria-associated endoplasmic reticulum membranes (MAM) to sensitize traditional chemotherapy and the new tumor therapeutic targets identified based on the signal pathways on the MAM have not been thoroughly discussed. In this review, we highlight the key roles of various signaling pathways at the ER-mitochondria contact site in tumorigenesis and focus on novel anticancer therapy strategies targeting potential targets at this contact site.
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Affiliation(s)
- Hongzheng Wu
- Department of Laboratory Medicine, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Wanxin Chen
- Department of Laboratory Medicine, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Zhenni Chen
- Department of Laboratory Medicine, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Xianping Li
- Department of Laboratory Medicine, The Second Xiangya Hospital, Central South University, Changsha, China
| | - Min Wang
- Department of Laboratory Medicine, The Second Xiangya Hospital, Central South University, Changsha, China.
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Li T, Fu J, Cheng J, Elfiky AA, Wei C, Fu J. New progresses on cell surface protein HSPA5/BiP/GRP78 in cancers and COVID-19. Front Immunol 2023; 14:1166680. [PMID: 37275848 PMCID: PMC10232979 DOI: 10.3389/fimmu.2023.1166680] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2023] [Accepted: 05/10/2023] [Indexed: 06/07/2023] Open
Abstract
Heat-shock-protein family A (Hsp70) member 5 (HSPA5), aliases GRP78 or BiP, is a protein encoded with 654 amino acids by the HSPA5 gene located on human chromosome 9q33.3. When the endoplasmic reticulum (ER) was stressed, HSPA5 translocated to the cell surface, the mitochondria, and the nucleus complexed with other proteins to execute its functions. On the cell surface, HSPA5/BiP/GRP78 can play diverse functional roles in cell viability, proliferation, apoptosis, attachments, and innate and adaptive immunity regulations, which lead to various diseases, including cancers and coronavirus disease 2019 (COVID-19). COVID-19 is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, which caused the pandemic since the first outbreak in late December 2019. HSPA5, highly expressed in the malignant tumors, likely plays a critical role in SARS-CoV-2 invasion/attack in cancer patients via tumor tissues. In the current study, we review the newest research progresses on cell surface protein HSPA5 expressions, functions, and mechanisms for cancers and SARS-CoV-2 invasion. The therapeutic and prognostic significances and prospects in cancers and COVID-19 disease by targeting HSPA5 are also discussed. Targeting HSPA5 expression by natural products may imply the significance in clinical for both anti-COVID-19 and anti-cancers in the future.
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Affiliation(s)
- Ting Li
- Key Laboratory of Epigenetics and Oncology, the Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, Sichuan, China
| | - Jiewen Fu
- Key Laboratory of Epigenetics and Oncology, the Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, Sichuan, China
| | - Jingliang Cheng
- Key Laboratory of Epigenetics and Oncology, the Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, Sichuan, China
| | - Abdo A. Elfiky
- Biophysics Department, Faculty of Science, Cairo University, Giza, Egypt
| | - Chunli Wei
- Key Laboratory of Epigenetics and Oncology, the Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, Sichuan, China
| | - Junjiang Fu
- Key Laboratory of Epigenetics and Oncology, the Research Center for Preclinical Medicine, Southwest Medical University, Luzhou, Sichuan, China
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Jiang RQ, Li QQ, Sheng R. Mitochondria associated ER membrane and cerebral ischemia: molecular mechanisms and therapeutic strategies. Pharmacol Res 2023; 191:106761. [PMID: 37028777 DOI: 10.1016/j.phrs.2023.106761] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/19/2023] [Accepted: 04/04/2023] [Indexed: 04/09/2023]
Abstract
Endoplasmic reticulum (ER) and mitochondria are two important organelles that are highly dynamic in mammalian cells. The physical connection between them is mitochondria associated ER membranes (MAM). In recent years, studies on endoplasmic reticulum and mitochondria have shifted from independent division to association and comparison, especially MAM has gradually become a research hotspot. MAM connects the two organelles, not only to maintain their independent structure and function, but also to promote metabolism and signal transduction between them. This paper reviews the morphological structure and protein localization of MAM, and briefly analyzes the functions of MAM in regulating Ca2+ transport, lipid synthesis, mitochondrial fusion and fission, endoplasmic reticulum stress and oxidative stress, autophagy and inflammation. Since ER stress and mitochondrial dysfunction are important pathological events in neurological diseases including ischemic stroke, MAM is likely to play an important role in cerebral ischemia by regulating the signaling of the two organelles and the crosstalk of the two pathological events.
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Affiliation(s)
- Rui-Qi Jiang
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases, Jiangsu Key laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences of Soochow University, Suzhou, China
| | - Qi-Qi Li
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases, Jiangsu Key laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences of Soochow University, Suzhou, China
| | - Rui Sheng
- Department of Pharmacology and Laboratory of Aging and Nervous Diseases, Jiangsu Key laboratory of Neuropsychiatric Diseases, College of Pharmaceutical Sciences of Soochow University, Suzhou, China.
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Zhou S, Zhong Z, Lu Y, Li Y, Yao H, Zhao Y, Guo T, Yang K, Li Y, Chen S, Huang K, Lian G. A LETM2-Regulated PI3K-Akt Signaling Axis Reveals a Prognostic and Therapeutic Target in Pancreatic Cancer. Cancers (Basel) 2022; 14:cancers14194722. [PMID: 36230646 PMCID: PMC9564284 DOI: 10.3390/cancers14194722] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Revised: 09/19/2022] [Accepted: 09/23/2022] [Indexed: 12/24/2022] Open
Abstract
Simple Summary LEMT2 was a newly discovered protein-encoding gene with little cancer research and an unclear mechanism. This study aimed to illustrate LETM2 as the crucial oncogene for tumor progression in pancreatic ductal adenocarcinoma (PDAC). We analyzed the expression level and prognostic value of LETM2 in multiple cancers using pan-cancer analysis and found that the LETM2 expression was the most significantly related to the dismal prognosis of PDAC. Immunohistochemical analyses showed that high LETM2 expression was correlated with poor outcomes of PDAC. In in vitro and in vivo experiments, LETM2 knockdown significantly inhibited tumor proliferation and metastasis, while LETM2 overexpression exerted the opposite effects. Then, we suggested that LETM2 may facilitate tumor progression by activating downstream PI3K-Akt signaling pathway in PDAC. In conclusion, the study enhanced our understanding of the LETM2-regulated PI3K-Akt signaling axis served as a prognostic and therapeutic target of pancreatic cancer. Abstract Pancreatic ductal adenocarcinoma (PDAC) is one of the highest mortalities malignant tumors, which is characterized by difficult diagnosis, rapid progression and high recurrence rate. Nevertheless, PDAC responds poorly to conventional therapies, which highlights the urgency to identify novel prognostic and therapeutic targets. LEMT2 was a newly discovered protein-encoding gene with little cancer research and an unclear mechanism. Thus, this study aimed to illustrate LETM2 as the crucial oncogene for tumor progression in PDAC. In this study, we analyzed the expression level and prognostic value of LETM2 in multiple cancers using pan-cancer analysis. The analyses based on the TCGA-GTEx dataset indicated that the LETM2 expression was obviously elevated in several cancers, and it was the most significantly related to the dismal prognosis of PDAC. Subsequently, we demonstrated the functional role and mechanism of LETM2 by clinical sample evaluation, and in in vitro and in vivo experiments. Immunohistochemical analyses showed that high expression of LETM2 was correlated with poor outcomes of PDAC. Moreover, we demonstrated that LETM2 knockdown significantly inhibited tumor proliferation and metastasis, and promoted cell apoptosis, while LETM2 overexpression exerted the opposite effects. Finally, the impairment caused by LETM2-knockdown could be recovered via excitation of the PI3k-Akt pathway in vitro and in vivo animal models, which suggested that LETM2 could activate the downstream PI3K-Akt pathway to participate in PDAC progression. In conclusion, the study enhanced our understanding of LETM2 as an oncogene hallmark of PDAC. LETM2 may facilitate tumor progression by activating the PI3K-Akt signaling pathway, which provides potential targets for the diagnosis, treatment, and prognosis of pancreatic cancer.
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Affiliation(s)
- Shurui Zhou
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Ziyi Zhong
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Yanzong Lu
- Department of Ophthalmology, No.903 Hospital of PLA Joint Logistic Support Force, Hangzhou 310013, China
| | - Yunlong Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Hanming Yao
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Yue Zhao
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Tairan Guo
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Kege Yang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Yaqing Li
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Shaojie Chen
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
| | - Kaihong Huang
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
- Correspondence: (K.H.); (G.L.)
| | - Guoda Lian
- Guangdong Provincial Key Laboratory of Malignant Tumor Epigenetics and Gene Regulation, Sun Yat-sen Memorial Hospital, Sun Yat-sen University, Guangzhou 510120, China
- Department of Gastroenterology, Sun Yat-sen Memorial Hospital, Zhongshan School of Medicine, Sun Yat-sen University, Guangzhou 510120, China
- Correspondence: (K.H.); (G.L.)
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