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Genetic variation determines VEGF-A plasma levels in cancer patients. Sci Rep 2018; 8:16332. [PMID: 30397360 PMCID: PMC6218528 DOI: 10.1038/s41598-018-34506-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 10/16/2018] [Indexed: 01/01/2023] Open
Abstract
Angiogenesis is essential in tumor biology and is regulated by vascular endothelial growth factor (VEGF) ligands and receptors. Here we aimed to discover genetic variants associated with levels of circulating angiogenic proteins in cancer patients. Plasma was collected at baseline in 216 pancreatic and 114 colorectal cancer patients. Thirty-one angiogenic proteins were measured by ELISA. 484,523 Single Nucleotide Polymorphisms (SNP) were tested for association with plasma levels for each protein in pancreatic cancer patients. Three top-ranked hits were then genotyped in colorectal cancer patients, where associations with the same proteins were measured. The results demonstrated rs2284284 and MCP1 (P-value = 6.7e–08), rs7504372 and VEGF-C (P-value = 9.8e–09), and rs7767396 and VEGF-A (P-value = 5.8e–09) were SNP-protein pairs identified in pancreatic cancer patients. In colorectal cancer patients, only rs7767396 (A > G) and VEGF-A was validated (P-value = 5.18e–05). The AA genotype of rs7767396 exhibited 2.04–2.3 and 2.7–3.4-fold higher VEGF-A levels than those with AG and GG genotypes. The G allele of rs7767396 reduces binding of the NF-AT1 transcription factor. In conclusion, a common genetic variant predicts the plasma levels of VEGF-A in cancer patients through altered binding of NF-AT1.
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Liu K, Tang Z, Huang A, Chen P, Liu P, Yang J, Lu W, Liao J, Sun Y, Wen S, Hu Y, Huang P. Glyceraldehyde-3-phosphate dehydrogenase promotes cancer growth and metastasis through upregulation of SNAIL expression. Int J Oncol 2017; 50:252-262. [PMID: 27878251 DOI: 10.3892/ijo.2016.3774] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2016] [Accepted: 11/08/2016] [Indexed: 11/06/2022] Open
Abstract
Glyceraldehyde-3-phosphate dehydrogenase (GAPDH) plays an important role in multiple cellular functions including metabolism and gene transcription. Our previous study showed that GAPDH expression was elevated in colon cancer and further upregulated in liver metastatic tissues, suggesting a possilbe role of GAPDH in promoting cancer metastasis. The present study was designed to investigate the underlying mechanism, using multiple experimental approaches including genetic silencing of GAPDH expression by short hairpin RNA (shRNA) and biochemcial/molecular analyses of the key events involved in glycolytic metabolism and epithelial-mesenchymal transition (EMT). We showed that silencing of GAPDH expression resulted in a significant reduction of glycolysis in colon cancer cell lines, accompanied by a decrease in cell proliferation and an apparent change in cell morphology associated with alterations in actin expression and phalloidine staining patterns. Furthermore, GAPDH suppression also caused a downregulation of gene expression involved in cancer stem-like cells and EMT. CHIP assay and co-immunoprecipitation revealed that GAPDH physically interacted with the transcriptional factor Sp1 and enhance the expression of SNAIL, a major regulator of EMT. Suppression of GAPDH expression resulted in a signficant decrease in SNAIL expression, leading to inhibition of EMT and attenuation of colon cancer cell migration in vitro and reduced metastasis in vivo. Overall, the present study suggests that GAPDH plays an important role in cancer metastasis by affecting EMT through regulation of Sp1-mediated SNAIL expression.
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Affiliation(s)
- Kaiyan Liu
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Zhenjie Tang
- Department of Thoracic and Cardiovascular Surgery, Second Xiangya Hospital of Central South University, Changsha, Hunan 410011, P.R. China
| | - Amin Huang
- Department of Medical Oncology, The Eastern Hospital of The First Affiliated Hospital, Sun Yat-sen University, Guangzhou, Guangdong 510700, P.R. China
| | - Ping Chen
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Panpan Liu
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Jing Yang
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Wenhua Lu
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Jianwei Liao
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Yicheng Sun
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Shijun Wen
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Yumin Hu
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
| | - Peng Huang
- Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center for Cancer Medicine, Guangzhou, Guangdong 510060, P.R. China
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Lin SP, Lee YT, Yang SH, Miller SA, Chiou SH, Hung MC, Hung SC. Colon cancer stem cells resist antiangiogenesis therapy-induced apoptosis. Cancer Lett 2012; 328:226-34. [PMID: 23017941 DOI: 10.1016/j.canlet.2012.08.036] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2012] [Revised: 08/30/2012] [Accepted: 08/31/2012] [Indexed: 12/22/2022]
Abstract
Antiangiogenesis is an efficient therapy for eliminating colon cancers, but because of recurrence it remains only palliative. We hypothesized that certain populations of tumor cells resist antiangiogenesis-induced apoptosis and explored the underlying mechanism. We demonstrated that the CD133(+) population of cells in colon cancer is resistant to anti-angiogenesis therapy. Additionally, we identified an anti-apoptotic signaling pathway responsible for this resistance involving PP2A, p38MAPK, MAPKAPK2, and Hsp27. Thus, this pathway may offer a new avenue to develop target therapy for colorectal cancer.
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Affiliation(s)
- Shih-Pei Lin
- Institute of Clinical Medicine, Faculty of Medicine, National Yang-Ming University, Taipei 112, Taiwan
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Kim JY, Jeon TJ, Bae BN, Kwon JE, Kim HJ, Park K, Shin E. The prognostic significance of growth factors and growth factor receptors in gastric adenocarcinoma. APMIS 2012; 121:95-104. [PMID: 23030255 DOI: 10.1111/j.1600-0463.2012.02942.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Accepted: 05/25/2012] [Indexed: 12/18/2022]
Abstract
We evaluated growth factors/receptors expression in gastric adenocarcinoma. Immunohistochemistry was used to evaluate epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), VEGF-D, VEGF receptor (VEGFR)-2, VEGFR-3, transforming growth factor (TGF)-α, TGF-β1, and TGF-β-RII in tissue microarrays of adenocarcinoma, dysplasia, metaplasia, and gastritis. In adenocarcinoma, the expression rates of EGFR, VEGF, VEGF-D, VEGFR-2, VEGFR-3, TGF-α, TGF-β1, and TGF-β-RII were 2.0%, 0%, 10.7%, 4.4%, 11.2%, 26.3%, 9.4%, and 19.5%, respectively. VEGF-D, TGF-α, TGF-β1, and TGF-β-RII expression rate were higher in adenocarcinoma than in other groups. TGF-β-RII expression was correlated with VEGFR-3, VEGF-D, and TGF-α expression in adenocarcinomas. Tumor location, histologic type, stage, lymphatic invasion, perineural invasion, angioinvasion, VEGF-D, and VEGFR-2 expressions were associated with patient survival in a log rank test and advanced stage and positive expression of VEGF-D were poor prognostic factors using Cox analysis. VEGF-D expression may be of prognostic value in gastric adenocarcinoma, whereas EGFR and TGF family expression may only have a minor influence.
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Affiliation(s)
- Jung Yeon Kim
- Department of Pathology, Inje University Sanggye Paik Hospital, Seoul, Korea.
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Kim JY, Bae BN, Kwon JE, Kim HJ, Park K. Prognostic significance of epidermal growth factor receptor and vascular endothelial growth factor receptor in colorectal adenocarcinoma. APMIS 2011; 119:449-59. [PMID: 21635552 DOI: 10.1111/j.1600-0463.2011.02752.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The purpose of this study was to evaluate the association between the expression of growth factors and the clinicopathological variables of colorectal adenocarcinoma. Immunohistochemistry and fluorescence in situ hybridization (FISH) were used to evaluate the amplification and expression of epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), VEGF-D, VEGF receptor (VEGFR)-2, VEGFR-3, transforming growth factor (TGF)-β1, and insulin-like growth factor-1 receptor (IGF-1R) in a tissue microarray of 292 colorectal adenocarcinomas. The expression of EGFR, VEGF, VEGF-D, VEGFR-2 and VEGFR-3 was detected in 5.1%, 10.0%, 6.8%, 5.2%, and 57.2%. EGFR expression was associated with angioinvasion (p < 0.05) and lymph node metastasis (p < 0.005). VEGFR-3 expression was higher in the rectum than in the colon (p < 0.05). VEGF expression correlated with VEGF-D (p < 0.05) and VEGFR-3 (p < 0.005) expression, while VEGF-D expression showed no significant association with VEGFR-2 or VEGFR-3. EGFR amplification was present in 10.6% and was not associated with EGFR protein expression. VEGFR-2 and VEGFR-3 expression levels were related to poor patient survival. Stage, perineural invasion, and lymph node metastasis were independent prognostic factors based on a Cox analysis. VEGFR-2 and VEGFR-3 expression are markers of a poor prognosis in patients with surgically resected colorectal adenocarcinoma, whereas EGFR has a minor influence.
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Affiliation(s)
- Jung Yeon Kim
- Department of Pathology, Inje University Sanggye Paik Hospital, Seoul, Korea.
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Pilot study of anti-angiogenic vaccine using fixed whole endothelium in patients with progressive malignancy after failure of conventional therapy. Eur J Cancer 2008; 44:383-90. [DOI: 10.1016/j.ejca.2007.10.018] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2007] [Revised: 10/16/2007] [Accepted: 10/22/2007] [Indexed: 11/22/2022]
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Baka S, Clamp AR, Jayson GC. A review of the latest clinical compounds to inhibit VEGF in pathological angiogenesis. Expert Opin Ther Targets 2007; 10:867-76. [PMID: 17105373 DOI: 10.1517/14728222.10.6.867] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Angiogenesis plays an important role in the formation of new blood vessels and is crucial for tumour development and progression. Imbalance between pro- and antiangiogenesis factors regulates the biological process of angiogenesis. The best characterised of the proangiogenic factors and the most potent is vascular endothelial growth factor (VEGF). The binding of VEGF to one of its transmembrane tyrosine kinase receptors, which are predominantly found on endothelial cells, results in receptor dimerisation, activation and autophosphorylation of the tyrosine kinase domain. This triggers a cascade of complex downstream signalling pathways. Several strategies targeting the VEGF signalling pathway have been developed. These include neutralising antibodies to VEGF (bevacizumab) or VEGF receptors (VEGFRs) (DC101), soluble VEGFR/VEGFR hybrids (VEGF-Trap), and tyrosine kinase inhibitors of VEGFRs (BAY43-9006, SU11248, ZD6474, AZD2171, PTK/ZK and others). Several of these agents are now being investigated in clinical trials.
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Affiliation(s)
- Sofia Baka
- Christie Hospital, Manchester, M20 4BX, UK.
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Affiliation(s)
- Carol S Viele
- University of California, San Francisco Medical Center, USA.
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Jozwiak J, Jozwiak S, Oldak M. Molecular activity of sirolimus and its possible application in tuberous sclerosis treatment. Med Res Rev 2006; 26:160-80. [PMID: 16329102 DOI: 10.1002/med.20049] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Sirolimus is one of the intensively investigated drugs with pluripotent activities. It binds to its intracellular receptor FKBP12 (FK506-binding protein 12), a member of the family of FK506-binding proteins, and inhibits the activity of mTOR, a serine/threonine kinase involved in numerous cell processes linked to cell growth control. The drug is currently registered for the prophylaxis of organ rejection and for use in coronary stents. However, unique characteristics of sirolimus make it a good candidate for anti-cancer therapy. Indeed, phase II and III clinical studies in humans with several types of neoplasms are already under way. The review describes molecular activity of sirolimus and its analogs, characteristic for specific applications, in view of very recent advances involving tuberous sclerosis complex (TSC)-mediated signaling pathways. Current studies with sirolimus performed in tuberous sclerosis animal models are presented. Possible application of sirolimus for treating tuberous sclerosis, disease caused by mutations of TSC proteins, is discussed.
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Affiliation(s)
- Jaroslaw Jozwiak
- Department of Histology and Embryology, Center for Biostructure Research, Medical University of Warsaw, Warsaw, Poland.
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Kamstock D, Guth A, Elmslie R, Kurzman I, Liggitt D, Coro L, Fairman J, Dow S. Liposome-DNA complexes infused intravenously inhibit tumor angiogenesis and elicit antitumor activity in dogs with soft tissue sarcoma. Cancer Gene Ther 2006; 13:306-17. [PMID: 16138118 DOI: 10.1038/sj.cgt.7700895] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Intravenous gene delivery using liposome-DNA complexes (LDC) has previously been shown to elicit antitumor activity, but only in rodent tumor models. Therefore, we conducted a study to determine in a large animal spontaneous tumor model whether intravenous infusions of LDC could target gene expression to cutaneous tumor tissues and whether repeated treatments had an effect on tumor growth or angiogenesis. A total of 13 dogs with cutaneous soft tissue sarcomas were enrolled in the study and were randomized to receive a series of 6 weekly infusions of LDC containing either canine endostatin DNA or DNA encoding an irrelevant gene (luciferase). Serial tumor biopsies were obtained to assess transgene expression, tumor microvessel density (MVD), and intratumoral leukocyte inflammatory responses. We found that intravenous infusion of LDC did not result in detectable gene expression in cutaneous tumor tissues. However, two of 13 treated dogs had objective tumor responses and eight dogs had stable disease during the treatment period. In addition, a significant decrease in tumor MVD was noted in six of 12 treated dogs at the completion of six treatments. These results suggest that intravenous infusions of LDC may elicit nonspecific antitumor activity and inhibit tumor angiogenesis.
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Affiliation(s)
- D Kamstock
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Ft Collins, 80523, USA
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Maharaj ASR, Saint-Geniez M, Maldonado AE, D'Amore PA. Vascular endothelial growth factor localization in the adult. THE AMERICAN JOURNAL OF PATHOLOGY 2006; 168:639-48. [PMID: 16436677 PMCID: PMC1606504 DOI: 10.2353/ajpath.2006.050834] [Citation(s) in RCA: 219] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Although vascular endothelial growth factor (VEGF) has been well studied in both developmental and pathological angiogenesis, its role in mature blood vessels is poorly understood. A growing body of observations, including the side effects of anti-VEGF therapies as well as the role of soluble VEGFR1 in preeclampsia, points to an important role for VEGF in maintenance of stable blood vessels. To better understand the potential function of VEGF in mature vessels, a survey of VEGF localization in adult mice was conducted. In adult VEGF-lacZ mice, VEGF was expressed in a cell-specific manner by cells overlying fenestrated and sinusoidal blood vessels, including podocytes, choroid plexus epithelium, and hepatocytes, as well as in tissues with high metabolic demands or with secretory functions, such as cardiac and skeletal myocytes, Leydig cells, prostatic epithelium, and salivary serous epithelium. VEGF was not detected in most endothelium but was specifically expressed by aortic endothelial cells where VEGFR2 was found to be phosphorylated, indicating an autocrine loop. Additionally, VEGFR2 was constitutively phosphorylated in the liver, lung, adipose, and kidney in vivo, providing evidence consistent with a role for VEGF in adult tissues. These observations support the concept that VEGF acts in the adult to stabilize mature vessels.
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Okaji Y, Tsuno NH, Saito S, Yoneyama S, Tanaka M, Nagawa H, Takahashi K. Vaccines targeting tumour angiogenesis--a novel strategy for cancer immunotherapy. Eur J Surg Oncol 2006; 32:363-70. [PMID: 16520018 DOI: 10.1016/j.ejso.2006.01.016] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2005] [Accepted: 01/26/2006] [Indexed: 01/30/2023] Open
Abstract
AIMS To review the concept of tumour angiogenesis and anti-angiogenic therapy, limitations of recently used anti-angiogenic therapeutics; provide an up-to-date overview of the growing number of reports on vaccines targeting tumour angiogenesis; and finally discuss potential complications and future directions in the development of more potent and specific vaccines. METHODS A literature search was carried out from PubMed for indexed articles. The most important articles were analysed and discussed. FINDINGS The search yielded a large number of important indexed published articles that were reviewed, screened and tracked for other relevant publications. The most relevant articles, including those previously published by authors, were analysed and discussed. CONCLUSIONS Recently, different vaccine strategies have been reported to inhibit tumour growth and metastasis by induction of specific cellular and/or humoral immunity against angiogenesis-associated antigens in pre-clinical models, suggesting effective combination of anti-angiogenesis and cancer immunotherapy. Evaluation of tumour endothelial cells and clinical phase I study of the vaccines are recently ongoing, and should give us better insight into the possibilities of this novel strategy for cancer immunotherapy.
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Affiliation(s)
- Y Okaji
- Department of Surgical Oncology, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
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Abstract
Advances in our understanding of the mechanisms underlying tumor progression suggest that angiogenesis plays a key role in gastrointestinal malignancies. Vascular endothelial growth factor (VEGF) has emerged as an important therapeutic target, and a variety of strategies to inhibit VEGF are under investigation. The approval of bevacizumab for use in patients with previously untreated metastatic colorectal cancer was based on clinical data suggesting that VEGF is a valid therapeutic target in this disease. As the data mature from ongoing trials, the role of angiogenesis inhibitors in the treatment of colon cancer and other gastrointestinal malignancies will be more clearly defined. Additional information is needed to identify the diseases and stages most likely to benefit from anti-angiogenic agents and the optimal sequences and therapeutic combinations that should be studied.
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Affiliation(s)
- Jonathan Whisenant
- San Francisco Comprehensive Cancer Center, University of California, San Francisco, San Francisco, CA 94115, USA
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Abstract
After over 30 years of theorizing, the use of angiogenesis inhibitors as anticancer therapy has finally moved from the realm of research to reality. Normal adult vasculature is generally quiescent in nature, with endothelial cells dividing approximately every 10 years. In contrast, the growth of tumors requires constant vascular growth and remodeling in order for solid tumors to grow beyond 1-2 mm(3) in size. Vascular endothelial growth factor (VEGF) and its receptors are key regulators of the process of angiogenesis, which makes them attractive therapeutic targets. A multitude of VEGF-targeted inhibitory agents are currently being investigated for the treatment of cancer. This review article focuses on recent developments in the use of angiogenesis inhibitors for the treatment of breast, lung, and colorectal cancers.
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Affiliation(s)
- Lee S Rosen
- John Wayne Cancer Institute and St. John's Health Center, Santa Monica, California, USA.
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Kim YR, Yudina A, Figueiredo J, Reichardt W, Hu-Lowe D, Petrovsky A, Kang HW, Torres D, Mahmood U, Weissleder R, Bogdanov AA. Detection of Early Antiangiogenic Effects in Human Colon Adenocarcinoma Xenografts: In vivo Changes of Tumor Blood Volume in Response to Experimental VEGFR Tyrosine Kinase Inhibitor. Cancer Res 2005; 65:9253-60. [PMID: 16230386 DOI: 10.1158/0008-5472.can-03-2619] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Antiangiogenesis is emerging as efficient strategy for targeting and potentially eliminating neoplastic tumor vessels. The main goal of this study was to establish whether absolute tumor blood volume (V(b)) change could be used as an early predictor of antiangiogenesis in ectopic and orthotopic colon carcinomas. To assess therapy-induced changes of V(b), we did comparative analysis of signal intensities in tumors and muscle using steady-state magnetic resonance imaging (MRI) assisted with an intravascular paramagnetic contrast agent [gadolinium-labeled protected graft copolymer (PGC-Gd)]. Athymic mice with implanted human MV522 tumors were treated with vascular endothelial growth factor type 2 receptor tyrosine kinase inhibitor (VEGFR2-TKI) that has been shown to inhibit VEGFR2 phosphorylation and tumor growth in vivo. Animals were imaged either after a single day or after a 1-week course of treatments. The measured V(b) in ectopic tumors was 2.5 +/- 1.5% of total tissue volume 1 week after the implantation (n = 8). Two doses of VEGFR2-TKI (25 mg/kg, p.o., b.i.d.) resulted in a decrease of V(b) to 1.3 +/- 0.3%. In orthotopic tumors, the measured V(b) was initially higher (11.9 +/- 2.0%); however, VEGFR2-TKI treatment also resulted in a statistically significant decrease of V(b). The absolute V(b) was not affected in the muscle as a result of treatments. MRI measurements were corroborated by using isotope and correlative histology experiments. Our results show that steady-state MRI is highly sensitive to early antiangiogenic effects caused by small molecule drugs.
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Affiliation(s)
- Young Ro Kim
- Center for Molecular Imaging Research, Massachusetts General Hospital, Charlestown, MA 01655, USA
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Pang R, Tse E, Poon RTP. Molecular pathways in hepatocellular carcinoma. Cancer Lett 2005; 240:157-69. [PMID: 16239065 DOI: 10.1016/j.canlet.2005.08.031] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2005] [Accepted: 08/31/2005] [Indexed: 01/18/2023]
Abstract
Research over the past decade has unraveled important molecular pathways involved in hepatocellular carcinoma (HCC), and several chromosomal and genetic aberrations have been identified to be responsible for initiation of the carcinogenic process. HBx protein and HCV core protein appear to play a pivotal role in hepatocarcinogenesis related to hepatitis B virus and hepatitis C virus, respectively. These viral oncoproteins allow cells to bypass some of the multi-steps in hepatocarcinogenesis, accounting for the etiological role of the two viruses in HCC. Understanding of the molecular pathways of HCC facilitates the development of novel molecular strategies for chemoprevention and therapy of HCC.
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Affiliation(s)
- Roberta Pang
- Department of Medicine, Centre for Cancer Research, The University of Hong Kong, Pokfulam, Hong Kong, China
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