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Ye QW, Liu YJ, Li JQ, Han M, Bian ZR, Chen TY, Li JP, Liu SL, Zou X. GJA4 expressed on cancer associated fibroblasts (CAFs)-A 'promoter' of the mesenchymal phenotype. Transl Oncol 2024; 46:102009. [PMID: 38833783 PMCID: PMC11190749 DOI: 10.1016/j.tranon.2024.102009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 05/09/2024] [Accepted: 05/25/2024] [Indexed: 06/06/2024] Open
Abstract
BACKGROUND Colorectal cancer (CRC) is the third most common cancer worldwide. Connexin is a transmembrane protein involved in gap junctions (GJs) formation. Our previous study found that connexin 37 (Cx37), encoded by gap junction protein alpha 4 (GJA4), expressed on fibroblasts acts as a promoter of CRC and is closely related to epithelial-mesenchymal transition (EMT) and tumor immune microenvironment. However, to date, the mechanism concerning the malignancy of GJA4 in tumor stroma has not been studied. METHODS Hematoxylin-eosin (HE) and immunohistochemical (IHC) staining were used to validate the expression and localization of GJA4. Using single-cell analysis, enrichment analysis, spatial transcriptomics, immunofluorescence staining (IF), Sirius red staining, wound healing and transwell assays, western blotting (WB), Cell Counting Kit-8 (CCK8) assay and in vivo experiments, we investigated the possible mechanisms of GJA4 in promoting CRC. RESULTS We discovered that in CRC, GJA4 on fibroblasts is involved in promoting fibroblast activation and promoting EMT through a fibroblast-dependent pathway. Furthermore, GJA4 may act synergistically with M2 macrophages to limit T cell infiltration by stimulating the formation of an immune-excluded desmoplasic barrier. Finally, we found a significantly correlation between GJA4 and pathological staging (P < 0.0001) or D2 dimer (R = 0.03, P < 0.05). CONCLUSION We have identified GJA4 expressed on fibroblasts is actually a promoter of the tumor mesenchymal phenotype. Our findings suggest that the interaction between GJA4+ fibroblasts and M2 macrophages may be an effective target for enhancing tumor immunotherapy.
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Affiliation(s)
- Qian-Wen Ye
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China; No.1 Clinical Medicial College, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, PR China
| | - Yuan-Jie Liu
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China; No.1 Clinical Medicial College, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, PR China
| | - Jia-Qi Li
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China; No.1 Clinical Medicial College, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, PR China
| | - Mei Han
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China
| | - Ze-Ren Bian
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China; No.1 Clinical Medicial College, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, PR China
| | - Tian-Yuan Chen
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China; No.1 Clinical Medicial College, Nanjing University of Chinese Medicine, Nanjing, Jiangsu, PR China
| | - Jie-Pin Li
- Jiangsu Province Key Laboratory of Tumor Systems Biology and Chinese Medicine, Nanjing, Jiangsu, PR China
| | - Shen-Lin Liu
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China.
| | - Xi Zou
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, Jiangsu, PR China; Jiangsu Province Key Laboratory of Tumor Systems Biology and Chinese Medicine, Nanjing, Jiangsu, PR China.
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Qiu D, He Y, Feng Y, Lin M, Lin Z, Zhang Z, Xiong Y, Hu Z, Ma S, Jin H, Liu J. Tumor perfusion enhancement by microbubbles ultrasonic cavitation reduces tumor glycolysis metabolism and alleviate tumor acidosis. Front Oncol 2024; 14:1424824. [PMID: 39091919 PMCID: PMC11291205 DOI: 10.3389/fonc.2024.1424824] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2024] [Accepted: 06/25/2024] [Indexed: 08/04/2024] Open
Abstract
The tumor microenvironment is increasingly acknowledged as a critical contributor to cancer progression, mediating genetic and epigenetic alterations. Beyond diverse cellular interactions from the microenvironment, physicochemical factors such as tumor acidosis also significantly affect cancer dynamics. Recent research has highlighted that tumor acidosis facilitates invasion, immune escape, metastasis, and resistance to therapies. Thus, noninvasive measurement of tumor acidity and the development of targeted interventions represent promising strategies in oncology. Techniques like contrast-enhanced ultrasound (CEUS) can effectively assess blood perfusion, while ultrasound-stimulated microbubble cavitation (USMC) has proven to enhance tumor blood perfusion. We therefore aimed to determine whether CEUS assesses tumor acidity and whether USMC treatment can modulate tumor acidity. Firstly, we tracked CEUS perfusion parameters in MCF7 tumor models and compared them with in vivo tumor pH recorded by pH microsensors. We found that the peak intensity and area under curve of tumor contrast-enhanced ultrasound correlated well with tumor pH. We further conducted USMC treatment on MCF7 tumor-bearing mice, tracked changes of tumor blood perfusion and tumor pH in different perfusion regions before and after the USMC treatment to assess its impact on tumor acidity and optimize therapeutic ultrasound pressure. We discovered that USMC with 1.0 Mpa significantly improved tumor blood perfusion and tumor pH. Furthermore, tumor vascular pathology and PGI2 assays indicated that improved tumor perfusion was mainly due to vasodilation rather than angiogenesis. More importantly, analysis of glycolysis-related metabolites and enzymes demonstrated USMC treatment can reduce tumor acidity by reducing tumor glycolysis. These findings support that CEUS may serve as a potential biomarker to assess tumor acidity and USMC is a promising therapeutic modality for reducing tumor acidosis.
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Affiliation(s)
- Danxia Qiu
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Yangcheng He
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Yuyi Feng
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Minhua Lin
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Zekai Lin
- Department of Radiology, The Second Clinical College, Guangzhou Medical University, Guangzhou, China
| | - Zhiyi Zhang
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Ying Xiong
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Zhiwen Hu
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Suihong Ma
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Hai Jin
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
| | - Jianhua Liu
- Department of Medical Ultrasound, The Second Affiliated Hospital, School of Medicine, South China University of Technology, Guangzhou, China
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Li JP, Liu YJ, Wang SS, Lu ZH, Ye QW, Zhou JY, Zou X, Chen YG. EBF1-COX4I2 signaling axis promotes a myofibroblast-like phenotype in cancer-associated fibroblasts (CAFs) and is associated with an immunosuppressive microenvironment. Int Immunopharmacol 2024; 139:112666. [PMID: 39002521 DOI: 10.1016/j.intimp.2024.112666] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2024] [Revised: 07/08/2024] [Accepted: 07/08/2024] [Indexed: 07/15/2024]
Abstract
Immunotherapy has limited response rates in colorectal cancer (CRC) due to an immunosuppressive tumor microenvironment (TME). Combining transcriptome sequencing, clinical specimens, and functional experiments, we identified a unique group of CAF subpopulations (COX4I2 + ) with inhibited mitochondrial respiration and enhanced glycolysis. Through bioinformatics predictions and luciferase reporter assays, we determined that EBF1 can upstreamly regulate COX4I2 transcription. COX4I2 + CAFs functionally and phenotypically resemble myofibroblasts, are important for the formation of the fibrotic TME, and are capable of activating the M2 phenotype of macrophages. In vitro experiments demonstrated that COX4I2 + CAFs promote immunosuppressive TME by blocking CD8 + T cell infiltration and inducing CD8 + T cell dysfunction. Using multiple independent cohorts, we also found a strong correlation between the immunotherapy response rate of CRC patients and COX4I2 expression in their tumors. Our results identify a CAF subpopulation characterized by activation of the EBF1-COX4I2 axis, and this group of CAFs can be targeted to improve cancer immunotherapy outcomes.
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Affiliation(s)
- Jie-Pin Li
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Jiangsu Province Key Laboratory of Tumor Systems Biology and Chinese Medicine, Nanjing, Jiangsu 210029, China
| | - Yuan-Jie Liu
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China
| | - Shuang-Shuang Wang
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China
| | - Zhi-Hua Lu
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China
| | - Qian-Wen Ye
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China
| | - Jin-Yong Zhou
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China
| | - Xi Zou
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Jiangsu Province Key Laboratory of Tumor Systems Biology and Chinese Medicine, Nanjing, Jiangsu 210029, China; Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor, Nanjing, Jiangsu 210029, China
| | - Yu-Gen Chen
- Jiangsu Province Hospital of Chinese Medicine, The Affiliated Hospital of Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Jiangsu Province Key Laboratory of Tumor Systems Biology and Chinese Medicine, Nanjing, Jiangsu 210029, China; Nanjing University of Chinese Medicine, Nanjing, Jiangsu 210029, China; Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor, Nanjing, Jiangsu 210029, China.
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Pedersen SHF. Acid-base transporters in the context of tumor heterogeneity. Pflugers Arch 2024; 476:689-701. [PMID: 38332178 DOI: 10.1007/s00424-024-02918-z] [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: 12/01/2023] [Revised: 01/20/2024] [Accepted: 01/29/2024] [Indexed: 02/10/2024]
Abstract
The copious metabolic acid production and -extrusion by cancer cells render poorly vascularized regions of solid tumors highly acidic. A growing list of proton - and bicarbonate transporters has been suggested to contribute to net acid extrusion from cancer cells, and/or been shown to be dysregulated and favor malignant development in various cancers. The great majority of these roles have been studied at the level of the cancer cells. However, recent advances in understanding of the cellular and physicochemical heterogeneity of solid tumors both enable and necessitate a reexamination of the regulation and roles of acid-base transporters in such malignancies. This review will briefly summarize the state-of-the-art, with a focus on the SLC9A and SLC4A families, for which most evidence is available. This is followed by a discussion of key concepts and open questions arising from recent insights and of the challenges that need to be tackled to address them. Finally, opportunities and challenges in therapeutic targeting of the acid-base transportome in cancers will be addressed.
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Affiliation(s)
- Stine Helene Falsig Pedersen
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Universitetsparken 13, 2100, Copenhagen, Denmark.
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5
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Michl J, White B, Monterisi S, Bodmer WF, Swietach P. Phenotypic screen of sixty-eight colorectal cancer cell lines identifies CEACAM6 and CEACAM5 as markers of acid resistance. Proc Natl Acad Sci U S A 2024; 121:e2319055121. [PMID: 38502695 PMCID: PMC10990159 DOI: 10.1073/pnas.2319055121] [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: 10/31/2023] [Accepted: 02/13/2024] [Indexed: 03/21/2024] Open
Abstract
Elevated cancer metabolism releases lactic acid and CO2 into the under-perfused tumor microenvironment, resulting in extracellular acidosis. The surviving cancer cells must adapt to this selection pressure; thus, targeting tumor acidosis is a rational therapeutic strategy to manage tumor growth. However, none of the major approved treatments are based explicitly on disrupting acid handling, signaling, or adaptations, possibly because the distinction between acid-sensitive and acid-resistant phenotypes is not clear. Here, we report pH-related phenotypes of sixty-eight colorectal cancer (CRC) cell lines by measuring i) extracellular acidification as a readout of acid production by fermentative metabolism and ii) growth of cell biomass over a range of extracellular pH (pHe) levels as a measure of the acid sensitivity of proliferation. Based on these measurements, CRC cell lines were grouped along two dimensions as "acid-sensitive"/"acid-resistant" versus "low metabolic acid production"/"high metabolic acid production." Strikingly, acid resistance was associated with the expression of CEACAM6 and CEACAM5 genes coding for two related cell-adhesion molecules, and among pH-regulating genes, of CA12. CEACAM5/6 protein levels were strongly induced by acidity, with a further induction under hypoxia in a subset of CRC lines. Lack of CEACAM6 (but not of CEACAM5) reduced cell growth and their ability to differentiate. Finally, CEACAM6 levels were strongly increased in human colorectal cancers from stage II and III patients, compared to matched samples from adjacent normal tissues. Thus, CEACAM6 is a marker of acid-resistant clones in colorectal cancer and a potential motif for targeting therapies to acidic regions within the tumors.
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Affiliation(s)
- Johanna Michl
- Department of Physiology, Anatomy and Genetics, University of Oxford, OxfordOX1 3PT, United Kingdom
| | - Bobby White
- Department of Physiology, Anatomy and Genetics, University of Oxford, OxfordOX1 3PT, United Kingdom
| | - Stefania Monterisi
- Department of Physiology, Anatomy and Genetics, University of Oxford, OxfordOX1 3PT, United Kingdom
| | - Walter F. Bodmer
- Department of Oncology, University of Oxford, OxfordOX3 7DQ, United Kingdom
| | - Pawel Swietach
- Department of Physiology, Anatomy and Genetics, University of Oxford, OxfordOX1 3PT, United Kingdom
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Zhang Y, Liu YJ, Mei J, Yang ZX, Qian XP, Huang W. An Analysis Regarding the Association Between DAZ Interacting Zinc Finger Protein 1 (DZIP1) and Colorectal Cancer (CRC). Mol Biotechnol 2024:10.1007/s12033-024-01065-1. [PMID: 38334905 DOI: 10.1007/s12033-024-01065-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Accepted: 12/21/2023] [Indexed: 02/10/2024]
Abstract
Colorectal cancer (CRC) is the third most common malignant disease worldwide, and its incidence is increasing, but the molecular mechanisms of this disease are highly heterogeneous and still far from being fully understood. Increasing evidence suggests that fibrosis mediated by abnormal activation of fibroblasts based in the microenvironment is associated with a poor prognosis. However, the function and pathogenic mechanisms of fibroblasts in CRC remain unclear. Here, combining scrna-seq and clinical specimen data, DAZ Interacting Protein 1 (DZIP1) was found to be expressed on fibroblasts and cancer cells and positively correlated with stromal deposition. Importantly, pseudotime-series analysis showed that DZIP1 levels were up-regulated in malignant transformation of fibroblasts and experimentally confirmed that DZIP1 modulates activation of fibroblasts and promotes epithelial-mesenchymal transition (EMT) in tumor cells. Further studies showed that DZIP1 expressed by tumor cells also has a driving effect on EMT and contributes to the recruitment of more fibroblasts. A similar phenomenon was observed in xenografted nude mice. And it was confirmed in xenograft mice that downregulation of DZIP1 expression significantly delayed tumor formation and reduced tumor size in CRC cells. Taken together, our findings suggested that DZIP1 was a regulator of the CRC mesenchymal phenotype. The revelation of targeting DZIP1 provides a new avenue for CRC therapy.
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Affiliation(s)
- Yu Zhang
- Comprehensive Cancer Center, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, 210008, Jiangsu, China
- Department of Medical Oncology, Affiliated Jinling Hospital, Medical School Nanjing University, Nanjing, 210029, Jiangsu, China
- Department of Oncology, Nanjing Tianyinshan Hospital, Nanjing, 211199, Jiangsu, China
| | - Yuan-Jie Liu
- Nanjing University of Chinese Medicine, Nanjing, 210029, Jiangsu, China
| | - Jia Mei
- Department of Pathology, Affiliated Jinling Hospital, Medical School Nanjing University, Nanjing, 210029, Jiangsu, China
| | - Zhao-Xu Yang
- Department of Medical Oncology, Affiliated Jinling Hospital, Medical School Nanjing University, Nanjing, 210029, Jiangsu, China
| | - Xiao-Ping Qian
- Comprehensive Cancer Center, Nanjing Drum Tower Hospital Clinical College of Nanjing Medical University, Nanjing, 210008, Jiangsu, China.
- Comprehensive Cancer Center, Nanjing Drum Tower Hospital, The Affiliated Hospital of Nanjing University Medical School, Clinical Cancer Institute of Nanjing University, Nanjing, 210008, Jiangsu, China.
| | - Wei Huang
- Department of Oncology, Jiangsu Province Hospital of Chinese Medicine, Affiliated Hospital of Nanjing University of Chinese Medicine, Hanzhong Road No.155, Nanjing, 210029, Jiangsu, China.
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Abstract
Cancers undergo sequential changes to proton (H+) concentration and sensing that are consequences of the disease and facilitate its further progression. The impact of protonation state on protein activity can arise from alterations to amino acids or their titration. Indeed, many cancer-initiating mutations influence pH balance, regulation or sensing in a manner that enables growth and invasion outside normal constraints as part of oncogenic transformation. These cancer-supporting effects become more prominent when tumours develop an acidic microenvironment owing to metabolic reprogramming and disordered perfusion. The ensuing intracellular and extracellular pH disturbances affect multiple aspects of tumour biology, ranging from proliferation to immune surveillance, and can even facilitate further mutagenesis. As a selection pressure, extracellular acidosis accelerates disease progression by favouring acid-resistant cancer cells, which are typically associated with aggressive phenotypes. Although acid-base disturbances in tumours often occur alongside hypoxia and lactate accumulation, there is now ample evidence for a distinct role of H+-operated responses in key events underpinning cancer. The breadth of these actions presents therapeutic opportunities to change the trajectory of disease.
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Affiliation(s)
- Pawel Swietach
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, UK.
| | - Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, Aarhus, Denmark.
| | - Stine Falsig Pedersen
- Department of Biology, University of Copenhagen, University of Copenhagen, Faculty of Science, København, Denmark.
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The Multifaceted Role of Connexins in Tumor Microenvironment Initiation and Maintenance. BIOLOGY 2023; 12:biology12020204. [PMID: 36829482 PMCID: PMC9953436 DOI: 10.3390/biology12020204] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Revised: 01/19/2023] [Accepted: 01/26/2023] [Indexed: 01/31/2023]
Abstract
Today's research on the processes of carcinogenesis and the vital activity of tumor tissues implies more attention be paid to constituents of the tumor microenvironment and their interactions. These interactions between cells in the tumor microenvironment can be mediated via different types of protein junctions. Connexins are one of the major contributors to intercellular communication. They form the gap junctions responsible for the transfer of ions, metabolites, peptides, miRNA, etc., between neighboring tumor cells as well as between tumor and stromal cells. Connexin hemichannels mediate purinergic signaling and bidirectional molecular transport with the extracellular environment. Additionally, connexins have been reported to localize in tumor-derived exosomes and facilitate the release of their cargo. A large body of evidence implies that the role of connexins in cancer is multifaceted. The pro- or anti-tumorigenic properties of connexins are determined by their abundance, localization, and functionality as well as their channel assembly and non-channel functions. In this review, we have summarized the data on the contribution of connexins to the formation of the tumor microenvironment and to cancer initiation and progression.
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Metabolic targeting of malignant tumors: a need for systemic approach. J Cancer Res Clin Oncol 2022; 149:2115-2138. [PMID: 35925428 DOI: 10.1007/s00432-022-04212-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2022] [Accepted: 07/14/2022] [Indexed: 12/09/2022]
Abstract
PURPOSE Dysregulated metabolism is now recognized as a fundamental hallmark of carcinogenesis inducing aggressive features and additional hallmarks. In this review, well-established metabolic changes displayed by tumors are highlighted in a comprehensive manner and corresponding therapeutical targets are discussed to set up a framework for integrating basic research findings with clinical translation in oncology setting. METHODS Recent manuscripts of high research impact and relevant to the field from PubMed (2000-2021) have been reviewed for this article. RESULTS Metabolic pathway disruption during tumor evolution is a dynamic process potentiating cell survival, dormancy, proliferation and invasion even under dismal conditions. Apart from cancer cells, though, tumor microenvironment has an acting role as extracellular metabolites, pH alterations and stromal cells reciprocally interact with malignant cells, ultimately dictating tumor-promoting responses, disabling anti-tumor immunity and promoting resistance to treatments. CONCLUSION In the field of cancer metabolism, there are several emerging prognostic and therapeutic targets either in the form of gene expression, enzyme activity or metabolites which could be exploited for clinical purposes; both standard-of-care and novel treatments may be evaluated in the context of metabolism rewiring and indeed, synergistic effects between metabolism-targeting and other therapies would be an attractive perspective for further research.
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Liu YJ, Han M, Li JP, Zeng SH, Ye QW, Yin ZH, Liu SL, Zou X. An Analysis Regarding the Association Between Connexins and Colorectal Cancer (CRC) Tumor Microenvironment. J Inflamm Res 2022; 15:2461-2476. [PMID: 35449599 PMCID: PMC9017696 DOI: 10.2147/jir.s361362] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2022] [Accepted: 04/06/2022] [Indexed: 12/12/2022] Open
Abstract
Background Gap junctions, as one of the major ways to maintain social connections between cells, are now considered as one of the potential regulators of tumor metastasis. However, to date, studies on the relationship between gap junctions and colorectal cancer (CRC) are limited. Methods We synthesized connexins-coding gene expression data from public Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) databases. Bioinformatics analysis was performed using R software and several database resources such as MEXPRESS database, Gene Set Cancer Analysis (GSCA) database, Human Protein Atlas (HPA) database, Tumor Immune Single Cell Hub (TISCH) database, Search Tool for Retrieval of Gene Interaction Relationships (STRING), and Cytoscape software, etc., to investigate the biological mechanisms that may be involved in connexins. Immunofluorescence and immunohistochemical staining were used to validate the expression and localization of GJA4. Results We found that CRC patients can be divided into two connexin clusters and that patients in cluster C1 had shorter survival than in cluster C2. The infiltration of M1 macrophages and NK cells was lower in cluster C1, while the levels of M2 macrophages and immune checkpoints were higher, indicating an immunosuppressed state in cluster C1. In addition, the epithelial–mesenchymal transition (EMT) phenotype was significantly activated in cluster C1. We observed that GJA4 was up-regulated in colorectal cancer tissues, which was related to poor prognosis. It was mainly expressed in fibroblasts, but the expression levels in normal intestinal epithelial cells were low. Finally, we found that GJA4 was associated with M2 macrophages and may be a potential immunosuppressive factor. Conclusion We found that there is a significant correlation between abnormal connexins expression and patients’ prognosis, and connexins play an important role in stromal-tumor interactions. Connexins, especially GJA4, can help enhance our understanding of tumor microenvironment (TME) and may guide more effective immunotherapeutic strategies.
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Affiliation(s)
- Yuan-jie Liu
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
- No. 1 Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China
| | - Mei Han
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
| | - Jie-pin Li
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
- No. 1 Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China
- Department of Oncology, Zhangjiagang TCM Hospital Affiliated to Nanjing University of Chinese Medicine, Zhangjiagang, People’s Republic of China
| | - Shu-hong Zeng
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
- No. 1 Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China
| | - Qian-wen Ye
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
- No. 1 Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China
| | - Zhong-hua Yin
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
- No. 1 Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China
| | - Shen-lin Liu
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
- No. 1 Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China
| | - Xi Zou
- Department of Oncology, Affiliated Hospital of Nanjing University of Chinese Medicine, Jiangsu Province Hospital of Chinese Medicine, Nanjing, People’s Republic of China
- No. 1 Clinical Medical College, Nanjing University of Chinese Medicine, Nanjing, People’s Republic of China
- Jiangsu Collaborative Innovation Center of Traditional Chinese Medicine in Prevention and Treatment of Tumor, Nanjing, People’s Republic of China
- Correspondence: Xi Zou; Shen-lin Liu, Email ;
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11
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Corchado-Cobos R, García-Sancha N, Mendiburu-Eliçabe M, Gómez-Vecino A, Jiménez-Navas A, Pérez-Baena MJ, Holgado-Madruga M, Mao JH, Cañueto J, Castillo-Lluva S, Pérez-Losada J. Pathophysiological Integration of Metabolic Reprogramming in Breast Cancer. Cancers (Basel) 2022; 14:cancers14020322. [PMID: 35053485 PMCID: PMC8773662 DOI: 10.3390/cancers14020322] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2021] [Revised: 01/03/2022] [Accepted: 01/06/2022] [Indexed: 02/04/2023] Open
Abstract
Simple Summary Tumors exhibit metabolic changes that differentiate them from the normal tissues from which they derive. These metabolic changes favor tumor growth, are primarily induced by cancer cells, and produce metabolic and functional changes in the surrounding stromal cells. There is a close functional connection between the metabolic changes in tumor cells and those that appear in the surrounding stroma. A better understanding of intratumoral metabolic interactions may help identify new vulnerabilities that will facilitate new, more individualized treatment strategies against cancer. We review the metabolic changes described in tumor and stromal cells and their functional changes and then consider, in depth, the metabolic interactions between the cells of the two compartments. Although these changes are generic, we illustrate them mainly with reference to examples in breast cancer. Abstract Metabolic changes that facilitate tumor growth are one of the hallmarks of cancer. The triggers of these metabolic changes are located in the tumor parenchymal cells, where oncogenic mutations induce an imperative need to proliferate and cause tumor initiation and progression. Cancer cells undergo significant metabolic reorganization during disease progression that is tailored to their energy demands and fluctuating environmental conditions. Oxidative stress plays an essential role as a trigger under such conditions. These metabolic changes are the consequence of the interaction between tumor cells and stromal myofibroblasts. The metabolic changes in tumor cells include protein anabolism and the synthesis of cell membranes and nucleic acids, which all facilitate cell proliferation. They are linked to catabolism and autophagy in stromal myofibroblasts, causing the release of nutrients for the cells of the tumor parenchyma. Metabolic changes lead to an interstitium deficient in nutrients, such as glucose and amino acids, and acidification by lactic acid. Together with hypoxia, they produce functional changes in other cells of the tumor stroma, such as many immune subpopulations and endothelial cells, which lead to tumor growth. Thus, immune cells favor tissue growth through changes in immunosuppression. This review considers some of the metabolic changes described in breast cancer.
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Affiliation(s)
- Roberto Corchado-Cobos
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
| | - Natalia García-Sancha
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
| | - Marina Mendiburu-Eliçabe
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
| | - Aurora Gómez-Vecino
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
| | - Alejandro Jiménez-Navas
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
| | - Manuel Jesús Pérez-Baena
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
| | - Marina Holgado-Madruga
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
- Departamento de Fisiología y Farmacología, Universidad de Salamanca, 37007 Salamanca, Spain
- Instituto de Neurociencias de Castilla y León (INCyL), Universidad de Salamanca, 37007 Salamanca, Spain
| | - Jian-Hua Mao
- Biological Systems and Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA;
- Berkeley Biomedical Data Science Center, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Javier Cañueto
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
- Departamento de Dermatología, Hospital Universitario de Salamanca, Paseo de San Vicente 58-182, 37007 Salamanca, Spain
- Complejo Asistencial Universitario de Salamanca, 37007 Salamanca, Spain
| | - Sonia Castillo-Lluva
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain
- Instituto de Investigaciones Sanitarias San Carlos (IdISSC), 28040 Madrid, Spain
- Correspondence: (S.C.-L.); (J.P-L.)
| | - Jesús Pérez-Losada
- Instituto de Biología Molecular y Celular del Cáncer (IBMCC-CIC), Universidad de Salamanca/CSIC, 37007 Salamanca, Spain; (R.C.-C.); (N.G.-S.); (M.M.-E.); (A.G.-V.); (A.J.-N.); (M.J.P.-B.); (J.C.)
- Instituto de Investigación Biosanitaria de Salamanca (IBSAL), 37007 Salamanca, Spain;
- Correspondence: (S.C.-L.); (J.P-L.)
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Gong K, Hong Q, Wu H, Wang F, Zhong L, Shen L, Xu P, Zhang W, Cao H, Zhan YY, Hu T, Hong X. Gap junctions mediate glucose transfer to promote colon cancer growth in three-dimensional spheroid culture. Cancer Lett 2022; 531:27-38. [DOI: 10.1016/j.canlet.2022.01.023] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2021] [Revised: 01/18/2022] [Accepted: 01/18/2022] [Indexed: 11/02/2022]
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13
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Ion Channels, Transporters, and Sensors Interact with the Acidic Tumor Microenvironment to Modify Cancer Progression. Rev Physiol Biochem Pharmacol 2021; 182:39-84. [PMID: 34291319 DOI: 10.1007/112_2021_63] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Solid tumors, including breast carcinomas, are heterogeneous but typically characterized by elevated cellular turnover and metabolism, diffusion limitations based on the complex tumor architecture, and abnormal intra- and extracellular ion compositions particularly as regards acid-base equivalents. Carcinogenesis-related alterations in expression and function of ion channels and transporters, cellular energy levels, and organellar H+ sequestration further modify the acid-base composition within tumors and influence cancer cell functions, including cell proliferation, migration, and survival. Cancer cells defend their cytosolic pH and HCO3- concentrations better than normal cells when challenged with the marked deviations in extracellular H+, HCO3-, and lactate concentrations typical of the tumor microenvironment. Ionic gradients determine the driving forces for ion transporters and channels and influence the membrane potential. Cancer and stromal cells also sense abnormal ion concentrations via intra- and extracellular receptors that modify cancer progression and prognosis. With emphasis on breast cancer, the current review first addresses the altered ion composition and the changes in expression and functional activity of ion channels and transporters in solid cancer tissue. It then discusses how ion channels, transporters, and cellular sensors under influence of the acidic tumor microenvironment shape cancer development and progression and affect the potential of cancer therapies.
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14
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Hypoxia and Extracellular Acidification as Drivers of Melanoma Progression and Drug Resistance. Cells 2021; 10:cells10040862. [PMID: 33918883 PMCID: PMC8070386 DOI: 10.3390/cells10040862] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Revised: 03/31/2021] [Accepted: 04/07/2021] [Indexed: 12/15/2022] Open
Abstract
Hypoxia and elevated extracellular acidification are prevalent features of solid tumors and they are often shown to facilitate cancer progression and drug resistance. In this review, we have compiled recent and most relevant research pertaining to the role of hypoxia and acidification in melanoma growth, invasiveness, and response to therapy. Melanoma represents a highly aggressive and heterogeneous type of skin cancer. Currently employed treatments, including BRAF V600E inhibitors and immune therapy, often are not effective due to a rapidly developing drug resistance. A variety of intracellular mechanisms impeding the treatment were discovered. However, the tumor microenvironment encompassing stromal and immune cells, extracellular matrix, and physicochemical conditions such as oxygen level or acidity, may also influence the therapy effectiveness. Hypoxia and acidification are able to reprogram the metabolism of melanoma cells, enhance their survival and invasiveness, as well as promote the immunosuppressive environment. For this reason, these physicochemical features of the melanoma niche and signaling pathways related to them emerge as potential therapeutic targets.
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15
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Role of Stromal Cells in Determining Tumor and Cancer Stem Cell Behaviors and Therapeutic Response. Cancers (Basel) 2020; 12:cancers12113162. [PMID: 33126471 PMCID: PMC7693000 DOI: 10.3390/cancers12113162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 10/27/2020] [Indexed: 11/17/2022] Open
Abstract
While research previously focused extensively on the tumor cells, over the last two decades, the tumor microenvironment (TME) has received increasing attention with a particular emphasis in its role in tumor development, metabolism, progression, and treatment response [...].
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16
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Parks SK, Mueller-Klieser W, Pouysségur J. Lactate and Acidity in the Cancer Microenvironment. ANNUAL REVIEW OF CANCER BIOLOGY-SERIES 2020. [DOI: 10.1146/annurev-cancerbio-030419-033556] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Fermentative glycolysis, an ancient evolved metabolic pathway, is exploited by rapidly growing tissues and tumors but also occurs in response to the nutritional and energetic demands of differentiated tissues. The lactic acid it produces is transported across cell membranes through reversible H+/lactate−symporters (MCT1 and MCT4) and is recycled in organs as a major metabolic precursor of gluconeogenesis and an energy source. Concentrations of lactate in the tumor environment, investigated utilizing an induced metabolic bioluminescence imaging (imBI) technique, appear to be dominant biomarkers of tumor response to irradiation and resistance to treatment. Suppression of lactic acid formation by genetic disruption of lactate dehydrogenases A and B in aggressive tumors reactivated OXPHOS (oxidative phosphorylation) to maintain xenograft tumor growth at a halved rate. In contrast, disruption of the lactic acid transporters MCT1/4 suppressed glycolysis, mTORC1, and tumor growth as a result of intracellular acidosis. Furthermore, the global reduction of tumor acidity contributes to activation of the antitumor immune responses, offering hope for future clinical applications.
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Affiliation(s)
- Scott K. Parks
- Department of Medical Biology, Centre Scientifique de Monaco (CSM), 98000 Monaco
| | - Wolfgang Mueller-Klieser
- Institute of Pathophysiology, University Medical Center, Johannes Gutenberg University Mainz, 55128 Mainz, Germany
| | - Jacques Pouysségur
- Department of Medical Biology, Centre Scientifique de Monaco (CSM), 98000 Monaco
- Institute for Research on Cancer and Aging, Nice (IRCAN), CNRS UMR 7284, INSERM U1081, Centre A. Lacassagne, University Côte d'Azur, 06189 Nice, France
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17
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Abstract
Acidic metabolic waste products accumulate in the tumor microenvironment because of high metabolic activity and insufficient perfusion. In tumors, the acidity of the interstitial space and the relatively well-maintained intracellular pH influence cancer and stromal cell function, their mutual interplay, and their interactions with the extracellular matrix. Tumor pH is spatially and temporally heterogeneous, and the fitness advantage of cancer cells adapted to extracellular acidity is likely particularly evident when they encounter less acidic tumor regions, for instance, during invasion. Through complex effects on genetic stability, epigenetics, cellular metabolism, proliferation, and survival, the compartmentalized pH microenvironment favors cancer development. Cellular selection exacerbates the malignant phenotype, which is further enhanced by acid-induced cell motility, extracellular matrix degradation, attenuated immune responses, and modified cellular and intercellular signaling. In this review, we discuss how the acidity of the tumor microenvironment influences each stage in cancer development, from dysplasia to full-blown metastatic disease.
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Affiliation(s)
- Ebbe Boedtkjer
- Department of Biomedicine, Aarhus University, DK-8000 Aarhus C, Denmark
| | - Stine F. Pedersen
- Department of Biology, University of Copenhagen, DK-2100 Copenhagen, Denmark
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18
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Elingaard-Larsen LO, Rolver MG, Sørensen EE, Pedersen SF. How Reciprocal Interactions Between the Tumor Microenvironment and Ion Transport Proteins Drive Cancer Progression. Rev Physiol Biochem Pharmacol 2020; 182:1-38. [PMID: 32737753 DOI: 10.1007/112_2020_23] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Solid tumors comprise two major components: the cancer cells and the tumor stroma. The stroma is a mixture of cellular and acellular components including fibroblasts, mesenchymal and cancer stem cells, endothelial cells, immune cells, extracellular matrix, and tumor interstitial fluid. The insufficient tumor perfusion and the highly proliferative state and dysregulated metabolism of the cancer cells collectively create a physicochemical microenvironment characterized by altered nutrient concentrations and varying degrees of hypoxia and acidosis. Furthermore, both cancer and stromal cells secrete numerous growth factors, cytokines, and extracellular matrix proteins which further shape the tumor microenvironment (TME), favoring cancer progression.Transport proteins expressed by cancer and stromal cells localize at the interface between the cells and the TME and are in a reciprocal relationship with it, as both sensors and modulators of TME properties. It has been amply demonstrated how acid-base and nutrient transporters of cancer cells enable their growth, presumably by contributing both to the extracellular acidosis and the exchange of metabolic substrates and waste products between cells and TME. However, the TME also impacts other transport proteins important for cancer progression, such as multidrug resistance proteins. In this review, we summarize current knowledge of the cellular and acellular components of solid tumors and their interrelationship with key ion transport proteins. We focus in particular on acid-base transport proteins with known or proposed roles in cancer development, and we discuss their relevance for novel therapeutic strategies.
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Affiliation(s)
- Line O Elingaard-Larsen
- Translational Type 2 Diabetes Research, Department of Clinical Research, Steno Diabetes Center Copenhagen, Gentofte, Denmark
| | - Michala G Rolver
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Ester E Sørensen
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark
| | - Stine F Pedersen
- Section for Cell Biology and Physiology, Department of Biology, Faculty of Science, University of Copenhagen, Copenhagen, Denmark.
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19
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Payen VL, Mina E, Van Hée VF, Porporato PE, Sonveaux P. Monocarboxylate transporters in cancer. Mol Metab 2019; 33:48-66. [PMID: 31395464 PMCID: PMC7056923 DOI: 10.1016/j.molmet.2019.07.006] [Citation(s) in RCA: 306] [Impact Index Per Article: 61.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 06/26/2019] [Accepted: 07/02/2019] [Indexed: 02/08/2023] Open
Abstract
Background Tumors are highly plastic metabolic entities composed of cancer and host cells that can adopt different metabolic phenotypes. For energy production, cancer cells may use 4 main fuels that are shuttled in 5 different metabolic pathways. Glucose fuels glycolysis that can be coupled to the tricarboxylic acid (TCA) cycle and oxidative phosphorylation (OXPHOS) in oxidative cancer cells or to lactic fermentation in proliferating and in hypoxic cancer cells. Lipids fuel lipolysis, glutamine fuels glutaminolysis, and lactate fuels the oxidative pathway of lactate, all of which are coupled to the TCA cycle and OXPHOS for energy production. This review focuses on the latter metabolic pathway. Scope of review Lactate, which is prominently produced by glycolytic cells in tumors, was only recently recognized as a major fuel for oxidative cancer cells and as a signaling agent. Its exchanges across membranes are gated by monocarboxylate transporters MCT1-4. This review summarizes the current knowledge about MCT structure, regulation and functions in cancer, with a specific focus on lactate metabolism, lactate-induced angiogenesis and MCT-dependent cancer metastasis. It also describes lactate signaling via cell surface lactate receptor GPR81. Major conclusions Lactate and MCTs, especially MCT1 and MCT4, are important contributors to tumor aggressiveness. Analyses of MCT-deficient (MCT+/- and MCT−/-) animals and (MCT-mutated) humans indicate that they are druggable, with MCT1 inhibitors being in advanced development phase and MCT4 inhibitors still in the discovery phase. Imaging lactate fluxes non-invasively using a lactate tracer for positron emission tomography would further help to identify responders to the treatments. In cancer, hypoxia and cell proliferation are associated to lactic acid production. Lactate exchanges are at the core of tumor metabolism. Transmembrane lactate trafficking depends on monocarboxylate transporters (MCTs). MCTs are implicated in tumor development and aggressiveness. Targeting MCTs is a therapeutic option for cancer treatment.
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Affiliation(s)
- Valéry L Payen
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium; Pole of Pediatrics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium; Louvain Drug Research Institute (LDRI), Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Erica Mina
- Department of Molecular Biotechnology and Health Science, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Vincent F Van Hée
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium
| | - Paolo E Porporato
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium; Department of Molecular Biotechnology and Health Science, Molecular Biotechnology Center, University of Torino, Torino, Italy
| | - Pierre Sonveaux
- Pole of Pharmacology & Therapeutics, Institut de Recherche Expérimentale et Clinique (IREC), Université catholique de Louvain (UCLouvain), Brussels, Belgium.
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Spatiotemporal pH Heterogeneity as a Promoter of Cancer Progression and Therapeutic Resistance. Cancers (Basel) 2019; 11:cancers11071026. [PMID: 31330859 PMCID: PMC6678451 DOI: 10.3390/cancers11071026] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 07/17/2019] [Accepted: 07/18/2019] [Indexed: 12/15/2022] Open
Abstract
Dysregulation of pH in solid tumors is a hallmark of cancer. In recent years, the role of altered pH heterogeneity in space, between benign and aggressive tissues, between individual cancer cells, and between subcellular compartments, has been steadily elucidated. Changes in temporal pH-related processes on both fast and slow time scales, including altered kinetics of bicarbonate-CO2 exchange and its effects on pH buffering and gradual, progressive changes driven by changes in metabolism, are further implicated in phenotypic changes observed in cancers. These discoveries have been driven by advances in imaging technologies. This review provides an overview of intra- and extracellular pH alterations in time and space reflected in cancer cells, as well as the available technology to study pH spatiotemporal heterogeneity.
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21
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Wang Y, Wang X, Chen S, Tian X, Zhang L, Huang Y, Tang C, Du J, Jin H. Sulfur Dioxide Activates Cl -/HCO 3 - Exchanger via Sulphenylating AE2 to Reduce Intracellular pH in Vascular Smooth Muscle Cells. Front Pharmacol 2019; 10:313. [PMID: 30971931 PMCID: PMC6446831 DOI: 10.3389/fphar.2019.00313] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 03/14/2019] [Indexed: 12/28/2022] Open
Abstract
Sulfur dioxide (SO2) is a colorless and irritating gas. Recent studies indicate that SO2 acts as the gas signal molecule and inhibits vascular smooth muscle cell (VSMC) proliferation. Cell proliferation depends on intracellular pH (pHi). Transmembrane cystein mutation of Na+- independent Cl-/HCO3 - exchanger (anion exchanger, AE) affects pHi. However, whether SO2 inhibits VSMC proliferation by reducing pHi is still unknown. Here, we investigated whether SO2 reduced pHi to inhibit the proliferation of VSMCs and explore its molecular mechanisms. Within a range of 50-200 μM, SO2 was found to lower the pHi in VSMCs. Concurrently, NH4Cl pre-perfusion showed that SO2 significantly activated AE, whereas the AE inhibitor 4,4'-diisothiocyanatostilbene- 2,20-disulfonic acid (DIDS) significantly attenuated the effect of SO2 on pHi in VSMCs. While 200 μM SO2 sulphenylated AE2, while dithiothreitol (DTT) blocked the sulphenylation of AE2 and subsequent AE activation by SO2, thereby restoring the pHi in VSMCs. Furthermore, DIDS pretreatment eliminated SO2-induced inhibition of PDGF-BB-stimulated VSMC proliferation. We report for the first time that SO2 inhibits VSMC proliferation in part by direct activation of the AE via posttranslational sulphenylation and induction of intracellular acidification.
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Affiliation(s)
- Yi Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Xiuli Wang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Selena Chen
- Division of Biological Sciences, University of California, San Diego, La Jolla, CA, United States
| | - Xiaoyu Tian
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Lulu Zhang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Yaqian Huang
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Chaoshu Tang
- Department of Physiology and Pathophysiology, Peking University Health Science Center, Beijing, China.,Key Laboratory of Molecular Cardiology, Ministry of Education, Beijing, China
| | - Junbao Du
- Department of Pediatrics, Peking University First Hospital, Beijing, China
| | - Hongfang Jin
- Department of Pediatrics, Peking University First Hospital, Beijing, China
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22
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Vander Linden C, Corbet C. Therapeutic Targeting of Cancer Stem Cells: Integrating and Exploiting the Acidic Niche. Front Oncol 2019; 9:159. [PMID: 30941310 PMCID: PMC6433943 DOI: 10.3389/fonc.2019.00159] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2018] [Accepted: 02/25/2019] [Indexed: 12/11/2022] Open
Abstract
Cancer stem cells (CSC) or tumor-initiating cells represent a small subpopulation of cells within the tumor bulk that share features with somatic stem cells, such as self-renewal and pluripotency. From a clinical point of view, CSC are thought to be the main drivers of tumor relapse in patients by supporting treatment resistance and dissemination to distant organs. Both genome instability and microenvironment-driven selection support tumor heterogeneity and enable the emergence of resistant cells with stem-like properties, when therapy is applied. Besides hypoxia and nutrient deprivation, acidosis is another selection barrier in the tumor microenvironment (TME) which provides a permissive niche to shape more aggressive and fitter cancer cell phenotypes. This review describes our current knowledge about the influence of the "acidic niche" on the stem-like phenotypic features of cancer cells. In addition, we briefly survey new therapeutic options that may help eradicate CSC by integrating and/or exploiting the acidic niche, and thereby contribute to prevent the occurrence of therapy resistance as well as metastatic dissemination.
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Affiliation(s)
| | - Cyril Corbet
- Pole of Pharmacology and Therapeutics (FATH), Institut de Recherche Expérimentale et Clinique, UCLouvain, Brussels, Belgium
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23
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Schwörer S, Vardhana SA, Thompson CB. Cancer Metabolism Drives a Stromal Regenerative Response. Cell Metab 2019; 29:576-591. [PMID: 30773467 PMCID: PMC6692899 DOI: 10.1016/j.cmet.2019.01.015] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Revised: 12/12/2018] [Accepted: 01/20/2019] [Indexed: 01/07/2023]
Abstract
The metabolic reprogramming associated with malignant transformation has led to a growing appreciation of the nutrients required to support anabolic cell growth. Less well studied is how cancer cells satisfy those demands in vivo, where they are dispersed within a complex microenvironment. Tumor-associated stromal components can support tumor growth by providing nutrients that supplement those provided by the local vasculature. These non-malignant stromal cells are phenotypically similar to those that accumulate during wound healing. Owing to their immediate proximity, stromal cells are inevitably affected by the metabolic activity of their cancerous neighbors. Until recently, a role for tumor cell metabolism in influencing the cell fate decisions of neighboring stromal cells has been underappreciated. Here, we propose that metabolites consumed and released by tumor cells act as paracrine factors that regulate the non-malignant cellular composition of a developing tumor by driving stromal cells toward a regenerative response that supports tumor growth.
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Affiliation(s)
- Simon Schwörer
- Memorial Sloan Kettering Cancer Center, Cancer Biology and Genetics Program, New York, NY 10065, USA
| | - Santosha A Vardhana
- Memorial Sloan Kettering Cancer Center, Cancer Biology and Genetics Program, New York, NY 10065, USA
| | - Craig B Thompson
- Memorial Sloan Kettering Cancer Center, Cancer Biology and Genetics Program, New York, NY 10065, USA.
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A Barter Economy in Tumors: Exchanging Metabolites through Gap Junctions. Cancers (Basel) 2019; 11:cancers11010117. [PMID: 30669506 PMCID: PMC6356692 DOI: 10.3390/cancers11010117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 01/16/2019] [Accepted: 01/18/2019] [Indexed: 02/07/2023] Open
Abstract
To produce physiological functions, many tissues require their cells to be connected by gap junctions. Such diffusive coupling is important in establishing a cytoplasmic syncytium through which cells can exchange signals, substrates and metabolites. Often the benefits of connectivity become apparent solely at the multicellular level, leading to the notion that cells work for a common good rather than exclusively in their self-interest. In some tumors, gap junctional connectivity between cancer cells is reduced or absent, but there are notable cases where it persists or re-emerges in late-stage disease. Diffusive coupling will blur certain phenotypic differences between cells, which may seem to go against the establishment of population heterogeneity, a central pillar of cancer that stems from genetic instability. Here, building on our previous measurements of gap junctional coupling between cancer cells, we use a computational model to simulate the role of connexin-assembled channels in exchanging lactate and bicarbonate ions down their diffusion gradients. Based on the results of these simulations, we propose that an overriding benefit of gap junctional connectivity may relate to lactate/bicarbonate exchange, which would support an elevated metabolic rate in hypoxic tumors. In this example of barter, hypoxic cancer cells provide normoxic neighbors with lactate for mitochondrial oxidation; in exchange, bicarbonate ions, which are more plentiful in normoxic cells, are supplied to hypoxic neighbors to neutralize the H+ ions co-produced glycolytically. Both cells benefit, and so does the tumor.
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26
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Koch A, Schwab A. Cutaneous pH landscape as a facilitator of melanoma initiation and progression. Acta Physiol (Oxf) 2019; 225:e13105. [PMID: 29802798 DOI: 10.1111/apha.13105] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 05/22/2018] [Accepted: 05/22/2018] [Indexed: 12/15/2022]
Abstract
Melanoma incidence is on the rise and currently causes the majority of skin cancer-related deaths. Yet, therapies for metastatic melanoma are still insufficient so that new concepts are essential. Malignant transformation of melanocytes and melanoma progression are intimately linked to the cutaneous pH landscape and its dysregulation in tumour lesions. The pH landscape of normal skin is characterized by a large pH gradient of up to 3 pH units between surface and dermis. The Na+ /H+ exchanger NHE1 is one of the major contributors of acidity in superficial skin layers. It is also activated by the most frequent mutation in melanoma, BRAFV 600E , thereby causing pH dysregulation during melanoma initiation. Melanoma progression is supported by an extracellular acidification and/or NHE1 activity which promote the escape of single melanoma cells from the primary tumour, migration and metastatic spreading. We propose that viewing melanoma against the background of the acid-base physiology of the skin provides a better understanding of the pathophysiology of this disease and allows the development of novel therapeutic concepts.
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Affiliation(s)
- A. Koch
- Institute of Physiology II; University of Münster; Münster Germany
| | - A. Schwab
- Institute of Physiology II; University of Münster; Münster Germany
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Silberman A, Goldman O, Boukobza Assayag O, Jacob A, Rabinovich S, Adler L, Lee JS, Keshet R, Sarver A, Frug J, Stettner N, Galai S, Persi E, Halpern KB, Zaltsman-Amir Y, Pode-Shakked B, Eilam R, Anikster Y, Nagamani SCS, Ulitsky I, Ruppin E, Erez A. Acid-Induced Downregulation of ASS1 Contributes to the Maintenance of Intracellular pH in Cancer. Cancer Res 2018; 79:518-533. [PMID: 30573518 DOI: 10.1158/0008-5472.can-18-1062] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Revised: 08/30/2018] [Accepted: 12/17/2018] [Indexed: 12/23/2022]
Abstract
Downregulation of the urea cycle enzyme argininosuccinate synthase (ASS1) by either promoter methylation or by HIF1α is associated with increased metastasis and poor prognosis in multiple cancers. We have previously shown that in normoxic conditions, ASS1 downregulation facilitates cancer cell proliferation by increasing aspartate availability for pyrimidine synthesis by the enzyme complex CAD. Here we report that in hypoxia, ASS1 expression in cancerous cells is downregulated further by HIF1α-mediated induction of miR-224-5p, making the cells more invasive and dependent on upstream substrates of ASS1 for survival. ASS1 was downregulated under acidic conditions, and ASS1-depleted cancer cells maintained a higher intracellular pH (pHi), depended less on extracellular glutamine, and displayed higher glutathione levels. Depletion of substrates of urea cycle enzymes in ASS1-deficient cancers decreased cancer cell survival. Thus, ASS1 levels in cancer are differentially regulated in various environmental conditions to metabolically benefit cancer progression. Understanding these alterations may help uncover specific context-dependent cancer vulnerabilities that may be targeted for therapeutic purposes. SIGNIFICANCE: Cancer cells in an acidic or hypoxic environment downregulate the expression of the urea cycle enzyme ASS1, which provides them with a redox and pH advantage, resulting in better survival.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/79/3/518/F1.large.jpg.
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Affiliation(s)
- Alon Silberman
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Omer Goldman
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | | | - Adi Jacob
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | - Shiran Rabinovich
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Lital Adler
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Joo Sang Lee
- Center for Bioinformatics and Computational Biology and Dept. of Computer Science, University of Maryland, College Park, Maryland.,Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, Maryland
| | - Rom Keshet
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Alona Sarver
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Julia Frug
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Noa Stettner
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.,Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Sivan Galai
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Erez Persi
- Computational Biology and Bioinformatics Branch (CBB), National Library of Medicine, National Center for Biotechnology Information (NCBI), NIH, Bethesda, Maryland
| | - Keren Bahar Halpern
- Department of Molecular Cell Biology, Weizmann Institute of Science, Rehovot, Israel
| | | | - Ben Pode-Shakked
- Metabolic Disease Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel-Hashomer, Israel.,The Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Raya Eilam
- Department of Veterinary Resources, Weizmann Institute of Science, Rehovot, Israel
| | - Yair Anikster
- Metabolic Disease Unit, Edmond and Lily Safra Children's Hospital, Sheba Medical Center, Tel-Hashomer, Israel.,The Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel
| | - Sandesh C S Nagamani
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas
| | - Igor Ulitsky
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel
| | - Eytan Ruppin
- Center for Bioinformatics and Computational Biology and Dept. of Computer Science, University of Maryland, College Park, Maryland.,Cancer Data Science Lab, National Cancer Institute, NIH, Bethesda, Maryland
| | - Ayelet Erez
- Department of Biological Regulation, Weizmann Institute of Science, Rehovot, Israel.
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Targeting cancer stem cells and their niche: perspectives for future therapeutic targets and strategies. Semin Cancer Biol 2018; 53:139-155. [PMID: 30081228 DOI: 10.1016/j.semcancer.2018.08.002] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Revised: 07/30/2018] [Accepted: 08/02/2018] [Indexed: 02/07/2023]
Abstract
A small subpopulation of cells within the bulk of tumors share features with somatic stem cells, in that, they are capable of self-renewal, they differentiate, and are highly resistant to conventional therapy. These cells have been referred to as cancer stem cells (CSCs). Recent reports support the central importance of a cancer stem cell-like niche that appears to help foster the generation and maintenance of CSCs. In response to signals provided by this microenvironment, CSCs express the tumorigenic characteristics that can drive tumor metastasis by the induction of epithelial-mesenchymal-transition (EMT) that in turn fosters the migration and recolonization of the cells as secondary tumors within metastatic niches. We summarize here recent advances in cancer stem cell research including the characterization of their genetic and epigenetic features, metabolic specialities, and crosstalk with aging-associated processes. Potential strategies for targeting CSCs, and their niche, by regulating CSCs plasticity, or therapeutic sensitivity is discussed. Finally, it is hoped that new strategies and related therapeutic approaches as outlined here may help prevent the formation of the metastatic niche, as well as counter tumor progression and metastatic growth.
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Mathematical Modeling of the Function of Warburg Effect in Tumor Microenvironment. Sci Rep 2018; 8:8903. [PMID: 29891989 PMCID: PMC5995918 DOI: 10.1038/s41598-018-27303-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 05/22/2018] [Indexed: 12/21/2022] Open
Abstract
Tumor cells are known for their increased glucose uptake rates even in the presence of abundant oxygen. This altered metabolic shift towards aerobic glycolysis is known as the Warburg effect. Despite an enormous number of studies conducted on the causes and consequences of this phenomenon, little is known about how the Warburg effect affects tumor growth and progression. We developed a multi-scale computational model to explore the detailed effects of glucose metabolism of cancer cells on tumorigenesis behavior in a tumor microenvironment. Despite glycolytic tumors, the growth of non-glycolytic tumor is dependent on a congruous morphology without markedly interfering with glucose and acid concentrations of the tumor microenvironment. Upregulated glucose metabolism helped to retain oxygen levels above the hypoxic limit during early tumor growth, and thus obviated the need for neo-vasculature recruitment. Importantly, simulating growth of tumors within a range of glucose uptake rates showed that there exists a spectrum of glucose uptake rates within which the tumor is most aggressive, i.e. it can exert maximal acidic stress on its microenvironment and most efficiently compete for glucose supplies. Moreover, within the same spectrum, the tumor could grow to invasive morphologies while its size did not markedly shrink.
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Abstract
The high metabolic demand of cancer cells leads to an accumulation of H+ ions in the tumour microenvironment. The disorganized tumour vasculature prevents an efficient wash-out of H+ ions released into the extracellular medium but also favours the development of tumour hypoxic regions associated with a shift towards glycolytic metabolism. Under hypoxia, the final balance of glycolysis, including breakdown of generated ATP, is the production of lactate and a stoichiometric amount of H+ ions. Another major source of H+ ions results from hydration of CO2 produced in the more oxidative tumour areas. All of these events occur at high rates in tumours to fulfil bioenergetic and biosynthetic needs. This Review summarizes the current understanding of how H+-generating metabolic processes segregate within tumours according to the distance from blood vessels and inversely how ambient acidosis influences tumour metabolism, reducing glycolysis while promoting mitochondrial activity. The Review also presents novel insights supporting the participation of acidosis in cancer progression via stimulation of autophagy and immunosuppression. Finally, recent advances in the different therapeutic modalities aiming to either block pH-regulatory systems or exploit acidosis will be discussed.
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Affiliation(s)
- Cyril Corbet
- Pole of Pharmacology and Therapeutics (FATH), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain, 53 Avenue Mounier B1.53.09, B-1200 Brussels, Belgium
| | - Olivier Feron
- Pole of Pharmacology and Therapeutics (FATH), Institut de Recherche Expérimentale et Clinique (IREC), Université Catholique de Louvain, 53 Avenue Mounier B1.53.09, B-1200 Brussels, Belgium
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Dovmark TH, Hulikova A, Niederer SA, Vaughan-Jones RD, Swietach P. Normoxic cells remotely regulate the acid-base balance of cells at the hypoxic core of connexin-coupled tumor growths. FASEB J 2017; 32:83-96. [PMID: 28883041 DOI: 10.1096/fj.201700480r] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2017] [Accepted: 08/14/2017] [Indexed: 12/19/2022]
Abstract
ATP fuels the removal of metabolic end-products, including H+ ions that profoundly modulate biological activities. Energetic resources in hypoxic tumor regions are constrained by low-yielding glycolysis, and any means of reducing the cost of acid extrusion, without compromising pH homeostasis, would therefore be advantageous for cancer cells. Some cancers express connexin channels that allow solute exchange between cells, and we propose that, via this route, normoxic cells supply hypoxic neighbors with acid-neutralizing HCO3- ions. This hypothesis was tested by imaging cytoplasmic pH in spheroidal tissue growths of connexin43-positive pancreatic cancer Colo357 cells during light-controlled H+ uncaging at the hypoxic core. Cytoplasmic acid retention at the core was halved in the presence of CO2/HCO3-, but this process requires a restorative HCO3- flux. The effect of CO2/HCO3- was ablated by connexin43 inhibition or knockdown. In connexin-decoupled spheroids, 4,4'-diisothiocyano-2,2'-stilbenedisulfonic acid (DIDS), an inhibitor of HCO3- uptake, had no effect on cytoplasmic [H+] in the H+-uncaging region, indicating that DIDS-sensitive transport is not an adequate pH-regulatory strategy therein. With intact connexin-coupling, acid retention at the core increased upon DIDS treatment, indicating that HCO3- ions are taken up actively by peripheral cells and then transmitted passively to cells at the hypoxic core. Thus, the energetic burden of pH regulation is offloaded from hypoxic cells onto metabolically altruistic normoxic neighbors.-Dovmark, T. H., Hulikova, A., Niederer, S. A., Vaughan-Jones, R. D., Swietach, P. Normoxic cells remotely regulate the acid-base balance of cells at the hypoxic core of connexin-coupled tumor growths.
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Affiliation(s)
- Tobias H Dovmark
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom, and
| | - Alzbeta Hulikova
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom, and
| | - Steven A Niederer
- Division of Imaging Sciences and Biomedical Engineering, St. Thomas' Hospital, London, United Kingdom
| | - Richard D Vaughan-Jones
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom, and
| | - Pawel Swietach
- Department of Physiology, Anatomy, and Genetics, University of Oxford, Oxford, United Kingdom, and
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Cortini M, Avnet S, Baldini N. Mesenchymal stroma: Role in osteosarcoma progression. Cancer Lett 2017; 405:90-99. [PMID: 28774797 DOI: 10.1016/j.canlet.2017.07.024] [Citation(s) in RCA: 104] [Impact Index Per Article: 14.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/19/2017] [Accepted: 07/23/2017] [Indexed: 12/21/2022]
Abstract
The initiation and progression of malignant tumors are supported by their microenvironment: cancer cells per se cannot explain growth and formation of the primary or metastasis, and a combination of proliferating tumor cells, cancer stem cells, immune cells mesenchymal stromal cells and/or cancer-associated fibroblasts all contribute to the tumor bulk. The interaction between these multiple players, under different microenvironmental conditions of biochemical and physical stimuli (i.e. oxygen tension, pH, matrix mechanics), regulates the production and biological activity of several soluble factors, extracellular matrix components, and extracellular vesicles that are needed for growth, maintenance, chemoresistance and metastatization of cancer. In osteosarcoma, a very aggressive cancer of young adults characterized by the extensive need for more effective therapies, this aspect has been only recently explored. In this view, we will discuss the role of stroma, with a particular focus on the mesenchymal stroma, contributing to osteosarcoma progression through inherent features for homing, neovascularization, paracrine cross-feeding, microvesicle secretion, and immune modulation, and also by responding to the changes of the microenvironment that are induced by tumor cells. The most recent advances in the molecular cues triggered by cytokines, soluble factors, and metabolites that are partially beginning to unravel the axis between stromal elements of mesenchymal origin and osteosarcoma cells, will be reviewed providing insights likely to be used for novel therapeutic approaches against sarcomas.
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Affiliation(s)
- Margherita Cortini
- Orthopaedic Pathophysiology and Regenerative Medicine Unit, Istituto Ortopedico Rizzoli, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Sofia Avnet
- Orthopaedic Pathophysiology and Regenerative Medicine Unit, Istituto Ortopedico Rizzoli, Bologna, Italy
| | - Nicola Baldini
- Orthopaedic Pathophysiology and Regenerative Medicine Unit, Istituto Ortopedico Rizzoli, Bologna, Italy; Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy.
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33
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Connexin-43 channels are a pathway for discharging lactate from glycolytic pancreatic ductal adenocarcinoma cells. Oncogene 2017; 36:4538-4550. [PMID: 28368405 PMCID: PMC5507299 DOI: 10.1038/onc.2017.71] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2016] [Revised: 01/27/2017] [Accepted: 02/14/2017] [Indexed: 12/13/2022]
Abstract
Glycolytic cancer cells produce large quantities of lactate that must be removed to sustain metabolism in the absence of oxidative phosphorylation. The only venting mechanism described to do this at an adequate rate is H+-coupled lactate efflux on monocarboxylate transporters (MCTs). Outward MCT activity is, however, thermodynamically inhibited by extracellular acidity, a hallmark of solid tumours. This inhibition would feedback unfavourably on metabolism and growth, raising the possibility that other venting mechanisms become important in under-perfused tumours. We investigated connexin-assembled gap junctions as an alternative route for discharging lactate from pancreatic ductal adenocarcinoma (PDAC) cells. Diffusive coupling (calcein transmission) in vitro was strong between Colo357 cells, weaker yet hypoxia-inducible between BxPC3 cells, and very low between MiaPaCa2 cells. Coupling correlated with levels of connexin-43 (Cx43), a protein previously linked to late-stage disease. Evoked lactate dynamics, imaged in Colo357 spheroids using cytoplasmic pH as a read-out, indicated that lactate anions permeate gap junctions faster than highly-buffered H+ ions. At steady-state, junctional transmission of lactate (a chemical base) from the spheroid core had an alkalinizing effect on the rim, producing therein a milieu conducive for growth. Metabolite assays demonstrated that Cx43 knockdown increased cytoplasmic lactate retention in Colo357 spheroids (diameter ~150 μm). MiaPaCa2 cells, which are Cx43 negative in monolayer culture, showed markedly increased Cx43 immunoreactivity at areas of invasion in orthotopic xenograft mouse models. These tissue areas were associated with chronic extracellular acidosis (as indicated by the marker LAMP2 near/at the plasmalemma), which can explain the advantage of junctional transmission over MCT in vivo. We propose that Cx43 channels are important conduits for dissipating lactate anions from glycolytic PDAC cells. Furthermore, lactate entry into the better-perfused recipient cells has a favourable alkalinizing effect and supplies substrate for oxidative phosphorylation. Cx43 is thus a novel target for influencing metabolite handling in junctionally-coupled tumours.
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White KA, Grillo-Hill BK, Barber DL. Cancer cell behaviors mediated by dysregulated pH dynamics at a glance. J Cell Sci 2017; 130:663-669. [PMID: 28202602 PMCID: PMC5339414 DOI: 10.1242/jcs.195297] [Citation(s) in RCA: 225] [Impact Index Per Article: 32.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Dysregulated pH is a common characteristic of cancer cells, as they have an increased intracellular pH (pHi) and a decreased extracellular pH (pHe) compared with normal cells. Recent work has expanded our knowledge of how dysregulated pH dynamics influences cancer cell behaviors, including proliferation, metastasis, metabolic adaptation and tumorigenesis. Emerging data suggest that the dysregulated pH of cancers enables these specific cell behaviors by altering the structure and function of selective pH-sensitive proteins, termed pH sensors. Recent findings also show that, by blocking pHi increases, cancer cell behaviors can be attenuated. This suggests ion transporter inhibition as an effective therapeutic approach, either singly or in combination with targeted therapies. In this Cell Science at a Glance article and accompanying poster, we highlight the interconnected roles of dysregulated pH dynamics in cancer initiation, progression and adaptation.
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Affiliation(s)
- Katharine A White
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA 94143, USA
| | - Bree K Grillo-Hill
- Department of Biological Sciences, San José State University, San José, CA 95192, USA
| | - Diane L Barber
- Department of Cell and Tissue Biology, University of California San Francisco, San Francisco, CA 94143, USA
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Targeting pH regulating proteins for cancer therapy-Progress and limitations. Semin Cancer Biol 2017; 43:66-73. [PMID: 28137473 DOI: 10.1016/j.semcancer.2017.01.007] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 01/24/2017] [Indexed: 12/21/2022]
Abstract
Tumour acidity induced by metabolic alterations and incomplete vascularisation sets cancer cells apart from normal cellular physiology. This distinguishing tumour characteristic has been an area of intense study, as cellular pH (pHi) disturbances disrupt protein function and therefore multiple cellular processes. Tumour cells effectively utilise pHi regulating machinery present in normal cells with enhancements provided by additional oncogenic or hypoxia induced protein modifications. This overall improvement of pH regulation enables maintenance of an alkaline pHi in the continued presence of external acidification (pHe). Considerable experimentation has revealed targets that successfully disrupt tumour pHi regulation in efforts to develop novel means to weaken or kill tumour cells. However, redundancy in these pH-regulating proteins, which include Na+/H+ exchangers (NHEs), carbonic anhydrases (CAs), Na+/HCO3- co-transporters (NBCs) and monocarboxylate transporters (MCTs) has prevented effective disruption of tumour pHi when individual protein targeting is performed. Here we synthesise recent advances in understanding both normoxic and hypoxic pH regulating mechanisms in tumour cells with an ultimate focus on the disruption of tumour growth, survival and metastasis. Interactions between tumour acidity and other cell types are also proving to be important in understanding therapeutic applications such as immune therapy. Promising therapeutic developments regarding pH manipulation along with current limitations are highlighted to provide a framework for future research directives.
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36
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Ring T, Nielsen S. Whole body acid-base modeling revisited. Am J Physiol Renal Physiol 2016; 312:F647-F653. [PMID: 28031171 DOI: 10.1152/ajprenal.00560.2016] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Revised: 12/14/2016] [Accepted: 12/21/2016] [Indexed: 01/15/2023] Open
Abstract
The textbook account of whole body acid-base balance in terms of endogenous acid production, renal net acid excretion, and gastrointestinal alkali absorption, which is the only comprehensive model around, has never been applied in clinical practice or been formally validated. To improve understanding of acid-base modeling, we managed to write up this conventional model as an expression solely on urine chemistry. Renal net acid excretion and endogenous acid production were already formulated in terms of urine chemistry, and we could from the literature also see gastrointestinal alkali absorption in terms of urine excretions. With a few assumptions it was possible to see that this expression of net acid balance was arithmetically identical to minus urine charge, whereby under the development of acidosis, urine was predicted to acquire a net negative charge. The literature already mentions unexplained negative urine charges so we scrutinized a series of seminal papers and confirmed empirically the theoretical prediction that observed urine charge did acquire negative charge as acidosis developed. Hence, we can conclude that the conventional model is problematic since it predicts what is physiologically impossible. Therefore, we need a new model for whole body acid-base balance, which does not have impossible implications. Furthermore, new experimental studies are needed to account for charge imbalance in urine under development of acidosis.
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Affiliation(s)
- Troels Ring
- Department of Nephrology, Aalborg University Hospital, Aalborg, Denmark; and .,Department of Health and Science Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
| | - Søren Nielsen
- Department of Health and Science Technology, Faculty of Medicine, Aalborg University, Aalborg, Denmark
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Richardson SL, Swietach P. Red blood cell thickness is evolutionarily constrained by slow, hemoglobin-restricted diffusion in cytoplasm. Sci Rep 2016; 6:36018. [PMID: 27777410 PMCID: PMC5078773 DOI: 10.1038/srep36018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 10/11/2016] [Indexed: 11/09/2022] Open
Abstract
During capillary transit, red blood cells (RBCs) must exchange large quantities of CO2 and O2 in typically less than one second, but the degree to which this is rate-limited by diffusion through cytoplasm is not known. Gas diffusivity is intuitively assumed to be fast and this would imply that the intracellular path-length, defined by RBC shape, is not a factor that could meaningfully compromise physiology. Here, we evaluated CO2 diffusivity (DCO2) in RBCs and related our results to cell shape. DCO2 inside RBCs was determined by fluorescence imaging of [H+] dynamics in cells under superfusion. This method is based on the principle that H+ diffusion is facilitated by CO2/HCO3- buffer and thus provides a read-out of DCO2. By imaging the spread of H+ ions from a photochemically-activated source (6-nitroveratraldehyde), DCO2 in human RBCs was calculated to be only 5% of the rate in water. Measurements on RBCs containing different hemoglobin concentrations demonstrated a halving of DCO2 with every 75 g/L increase in mean corpuscular hemoglobin concentration (MCHC). Thus, to compensate for highly-restricted cytoplasmic diffusion, RBC thickness must be reduced as appropriate for its MCHC. This can explain the inverse relationship between MCHC and RBC thickness determined from >250 animal species.
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Affiliation(s)
- Sarah L Richardson
- Department of Physiology, Anatomy and Genetics, Oxford OX1 3PT, European Union, United Kingdom
| | - Pawel Swietach
- Department of Physiology, Anatomy and Genetics, Oxford OX1 3PT, European Union, United Kingdom
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