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Liu J, Shi Y, Han J, Zhang Y, Cao Z, Cheng J. Quantitative Tracking Tumor Suppression Efficiency of Human Umbilical Cord-Derived Mesenchymal Stem Cells by Bioluminescence Imaging in Mice Hepatoma Model. Int J Stem Cells 2020; 13:104-115. [PMID: 31887848 PMCID: PMC7119203 DOI: 10.15283/ijsc19098] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 10/07/2019] [Accepted: 11/07/2019] [Indexed: 01/02/2023] Open
Abstract
Background and Objectives Tracking of the tumor progression by MSCs-based therapy is being increasingly important in evaluating relative therapy effectively. Herein, Bioluminescence imaging (BLI) technology was used to dynamically and quantitatively track the hepatocellular carcinoma suppressive effects by human umbilical cord mesenchymal stem cells (UC-MSCs). Methods and Results The stem cells present typical phenotypic characteristics and differentiation ability by morphology and flow cytometry analysis of marker expression. Then, the growth inhibition effect of conditioned medium and UC-MSC on H7402 cells was studied. It is found both the conditioned medium and UC-MSC can effectively decrease the proliferation of H7402 cells compared with the control group. Meanwhile, the relative migration of UC-MSC to H7402 is also increased through the transwell migration assay. In addition, a mice hepatoma tumor model was built by H7402 cells which can express a pLenti-6.3/DEST-CMV-luciferase 2-mKate2 gene. The effect of stem cells on growth inhibition of tumor in a mice transplantation model was dynamically monitored by bioluminescence imaging within 5 weeks. It has shown the bioluminescence signal intensity of the tumor model was significantly higher than that of the UC-MSC co-acting tumor model, indicating that the inhibition of UC-MSC on liver cancer resulted in low expression of bioluminescent signals. Conclusions The microenvironment of UC-MSCs can effectively inhibit the growth of liver cancer cells, and this therapeutic effect can be dynamically and quantitatively monitored in vivo by BLI. This is of great significance for the imaging research and application of stem cells in anticancer therapy.
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Affiliation(s)
- Jingjing Liu
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yupeng Shi
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jing Han
- Department of Pathology, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Yong Zhang
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Zhenghao Cao
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jingliang Cheng
- Department of MRI, The First Affiliated Hospital of Zhengzhou University, Zhengzhou, China
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Lee YR, Park SY. P53 expression in hepatocellular carcinoma: influence on the radiotherapeutic response of the hepatocellular carcinoma. Clin Mol Hepatol 2015; 21:230-1. [PMID: 26526818 PMCID: PMC4612283 DOI: 10.3350/cmh.2015.21.3.230] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/07/2015] [Revised: 08/27/2015] [Indexed: 12/22/2022] Open
Affiliation(s)
- Yu Rim Lee
- Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea
| | - Soo Young Park
- Department of Internal Medicine, Kyungpook National University Hospital, Daegu, Korea
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Gomes AR, Abrantes AM, Brito AF, Laranjo M, Casalta-Lopes JE, Gonçalves AC, Sarmento-Ribeiro AB, Botelho MF, Tralhão JG. Influence of P53 on the radiotherapy response of hepatocellular carcinoma. Clin Mol Hepatol 2015; 21:257-67. [PMID: 26527121 PMCID: PMC4612287 DOI: 10.3350/cmh.2015.21.3.257] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/01/2015] [Revised: 06/13/2015] [Accepted: 07/27/2015] [Indexed: 12/30/2022] Open
Abstract
Background/Aims Hepatocellular carcinoma (HCC) is one of the most common cancers worldwide, and it has a poor prognosis and few therapeutic options. Radiotherapy is one of the most effective forms of cancer treatment, and P53 protein is one of the key molecules determining how a cell responds to radiotherapy. The aim of this study was to determine the therapeutic efficacy of iodine-131 in three human HCC cell lines. Methods Western blotting was used to measure P53 expression. The effects of radiotherapy with iodine-131 were assessed by using the clonogenic assay to evaluate cell survival. Flow cytometry was carried out to examine the effects of iodine-131 on cell death, oxidative stress, reduced intracellular glutathione expression, the mitochondrial membrane potential, and the cell cycle. Results The P53 protein was not expressed in Hep3B2.1-7 cells, was expressed at normal levels in HepG2 cells, and was overexpressed in HuH7 cells. P53 expression in the HuH7 and HepG2 cell lines increased after internal and external irradiation with iodine-131. Irradiation induced a decrease in cell survival and led to a decrease in cell viability in all of the cell lines studied, accompanied by cell death via late apoptosis/necrosis and necrosis. Irradiation with 131-iodine induced mostly cell-cycle arrest in the G0/G1 phase. Conclusions These results suggest that P53 plays a key role in the radiotherapy response of HCC.
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Affiliation(s)
- Ana R Gomes
- Biophysics Unit, Faculty of Medicine of University of Coimbra, Coimbra, Portugal
| | - Ana M Abrantes
- Biophysics Unit, Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; CNC.IBILI, University of Coimbra, Coimbra, Portugal
| | - Ana F Brito
- Biophysics Unit, Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; CNC.IBILI, University of Coimbra, Coimbra, Portugal
| | - Mafalda Laranjo
- Biophysics Unit, Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; CNC.IBILI, University of Coimbra, Coimbra, Portugal
| | - João E Casalta-Lopes
- Biophysics Unit, Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal
| | - Ana C Gonçalves
- Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; CNC.IBILI, University of Coimbra, Coimbra, Portugal. ; Applied Molecular Biology and Hematology Group, Faculty of Medicine of University of Coimbra, Coimbra, Portugal
| | - Ana B Sarmento-Ribeiro
- Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; CNC.IBILI, University of Coimbra, Coimbra, Portugal. ; Applied Molecular Biology and Hematology Group, Faculty of Medicine of University of Coimbra, Coimbra, Portugal
| | - Maria F Botelho
- Biophysics Unit, Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; CNC.IBILI, University of Coimbra, Coimbra, Portugal
| | - José G Tralhão
- Biophysics Unit, Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; Center of Investigation on Environmental, Genetics and Oncobiology (CIMAGO), Faculty of Medicine of University of Coimbra, Coimbra, Portugal. ; Surgical Department A, CHUC, Coimbra, Portugal
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Wray CJ, Harvin JA, Silberfein EJ, Ko TC, Kao LS. Pilot prognostic model of extremely poor survival among high-risk hepatocellular carcinoma patients. Cancer 2012; 118:6118-25. [DOI: 10.1002/cncr.27649] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2012] [Revised: 02/29/2012] [Accepted: 03/20/2012] [Indexed: 11/08/2022]
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Choi D, Lim HK, Rhim H. Concurrent and subsequent radiofrequency ablation combined with hepatectomy for hepatocellular carcinomas. World J Gastrointest Surg 2010; 2:137-42. [PMID: 21160862 PMCID: PMC2999226 DOI: 10.4240/wjgs.v2.i4.137] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2009] [Revised: 12/25/2009] [Accepted: 01/02/2010] [Indexed: 02/06/2023] Open
Abstract
Partial hepatectomy has long been the standard treatment modality for patients with hepatocellular carcinoma (HCC), although the majority of patients with HCCs are not candidates for curative resection. Radiofrequency ablation (RFA) has been widely used as the preferred locoregional therapy. RFA and hepatectomy can be complementary to each other for the treatment of multifocal HCCs. Combining hepatectomy with RFA permits the removal of larger tumors while simultaneously ablating any smaller residual tumors. By using this combination treatment, more patients might become candidates for curative resection. For treating recurrent tumors involving the liver after hepatectomy, RFA has been performed recently instead of transcatheter arterial chemoembolization or ethanol ablation. Many retrospective studies on the combination of RFA and hepatectomy demonstrate favorable results of effectiveness and safety. However, further investigation of prospective design will be needed to confirm these encouraging results.
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Affiliation(s)
- Dongil Choi
- Dongil Choi, Hyo K Lim, Hyunchul Rhim, Department of Radiology and Center for Imaging Science, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul 135-710, South Korea
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Combined hepatectomy and radiofrequency ablation for multifocal hepatocellular carcinoma: a case report. CASES JOURNAL 2009; 2:7987. [PMID: 19830036 PMCID: PMC2740137 DOI: 10.4076/1757-1626-2-7987] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/27/2009] [Accepted: 05/28/2009] [Indexed: 11/08/2022]
Abstract
Introduction At the present time, the best possible choice for the local management of a multifocal hepatocellular carcinoma (HCC) developing on liver cirrhosis is multimodal treatment of the disease. Combined approach based on simultaneous radiofrequency ablation (RFA) together with limited surgical resection represents a valid choice of treatment. Case presentation A 75-year-old white female patient affected of HCV-associated cirrhosis in Child-Pugh’s functional class A5, developed a bifocal HCC. The patient had undergone a limited surgical resection together with simultaneous RFA, without intraoperative and postoperative surgical complications. At 36 months after surgery, still shows no sign of disease relapse. Conclusion This strategy directed at the management of multifocal HCC, may prove more useful for the reduction of surgical risk and post-operative progression of the liver cirrhosis than large-scale hepatectomy, since it presents no peri-operative mortality and a complication rate of less than 10%.
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Goldman R, Ressom HW, Varghese RS, Goldman L, Bascug G, Loffredo CA, Abdel-Hamid M, Gouda I, Ezzat S, Kyselova Z, Mechref Y, Novotny MV. Detection of hepatocellular carcinoma using glycomic analysis. Clin Cancer Res 2009; 15:1808-13. [PMID: 19223512 DOI: 10.1158/1078-0432.ccr-07-5261] [Citation(s) in RCA: 118] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
PURPOSE Hepatocellular carcinoma (HCC) represents an increasing health problem in the United States. Serum alpha-fetoprotein, the currently used clinical marker, is elevated in only approximately 60% of HCC patients; therefore, the identification of additional markers is expected to have significant public health impact. The objective of our study was to quantitatively assess N-glycans originating from serum glycoproteins as alternative markers for the detection of HCC. EXPERIMENTAL DESIGN We used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for quantitative comparison of 83 N-glycans in serum samples of 202 participants (73 HCC cases, 77 age- and gender-matched cancer-free controls, and 52 patients with chronic liver disease). N-glycans were enzymatically released from serum glycoproteins and permethylated before mass spectrometric quantification. RESULTS The abundance of 57 N-glycans was significantly altered in HCC patients compared with controls. The sensitivity of six individual glycans evaluated for separation of HCC cases from population controls ranged from 73% to 90%, and the specificity ranged from 36% to 91%. A combination of three selected N-glycans was sufficient to classify HCC with 90% sensitivity and 89% specificity in an independent validation set of patients with chronic liver disease. The three N-glycans remained associated with HCC after adjustment for chronic viral infection and other known covariates, whereas the other glycans increased significantly at earlier stages of the progression of chronic viral infection to HCC. CONCLUSION A set of three identified N-glycans is sufficient for the detection of HCC with 90% prediction accuracy in a population with high rates of hepatitis C viral infection. Further evaluation of a wider clinical utility of these candidate markers is warranted.
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Affiliation(s)
- Radoslav Goldman
- Department of Oncology, Georgetown University, Washington, District of Columbia 20057-1469, USA.
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Goldman R, Ressom HW, Abdel-Hamid M, Goldman L, Wang A, Varghese RS, An Y, Loffredo CA, Drake SK, Eissa SA, Gouda I, Ezzat S, Moiseiwitsch FS. Candidate markers for the detection of hepatocellular carcinoma in low-molecular weight fraction of serum. Carcinogenesis 2007; 28:2149-53. [PMID: 17724376 PMCID: PMC2204039 DOI: 10.1093/carcin/bgm177] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
Hepatocellular carcinoma (HCC) represents an important public health problem in Egypt where up to 90% of HCC cases are attributable to hepatitis C viral (HCV) infection. Serum alpha-fetoprotein is elevated in only approximately 60% of HCC patients. The development of effective markers for the detection of HCC could have an impact on cancer mortality and significant public health implications worldwide. The objective of our study was to assess six candidate markers for detection of HCC identified by mass spectrometric analysis of enriched serum. The study examined 78 HCC cases and 72 age- and gender-matched cancer-free controls recruited from the Egyptian population. Matrix-assisted laser desorption-ionization time-of-flight mass spectrometric analysis of enriched low-molecular weight fraction of serum was used for identification of the candidate markers. Our analyses show that all six candidate markers are associated with HCC after adjustment for important covariates including HCV and hepatitis B viral infections. The marker candidates are independently predictive of HCC with areas under the receiver operating characteristic (AuROC) curve ranging from 63-93%. A combination of the six markers improves prediction accuracy to 100% sensitivity, 91% specificity and 98% AuROC curve in an independent test set of 50 patients. Two of the candidate markers were identified by sequencing as fragments of complement C3 and C4. In conclusion, a set of six peptides distinguished with high prediction accuracy HCC from controls in an Egyptian population with a high rate of chronic HCV infection. Further evaluation of these marker candidates for the diagnosis of HCC is needed.
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Affiliation(s)
- Radoslav Goldman
- Georgetown University, Lombardi Comprehensive Cancer Center, 3970 Reservoir Road Northwest, Washington, DC 20057, USA.
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Choi D, Lim HK, Joh JW, Kim SJ, Kim MJ, Rhim H, Kim YS, Yoo BC, Paik SW, Park CK. Combined hepatectomy and radiofrequency ablation for multifocal hepatocellular carcinomas: long-term follow-up results and prognostic factors. Ann Surg Oncol 2007; 14:3510-8. [PMID: 17653800 DOI: 10.1245/s10434-007-9492-7] [Citation(s) in RCA: 54] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2007] [Accepted: 05/24/2007] [Indexed: 12/13/2022]
Abstract
BACKGROUND For multifocal hepatocellular carcinomas (HCCs) that are untreatable with resection only, locoregional therapies added to hepatectomy have been introduced. However, some preliminary reports have documented average survival results and relatively high complication rates. We evaluated the long-term survival results and safety of combined hepatectomy and radiofrequency ablation (RFA) in patients with HCCs and assessed the prognostic factors affecting their survival. METHODS A total of 53 patients who had 148 HCCs in their livers underwent hepatectomy combined with ultrasound-guided intraoperative RFA. The mean diameter of the 82 resected tumors was 4.8 cm (range 1.3-21.0 cm) and that of 66 ablated tumors was 1.5 cm (range 0.8-3.5 cm). We evaluated the primary effectiveness rates, survival rates, and complications. In addition, we assessed the prognostic factors associated with the survival rates using Cox proportional hazard models. RESULTS The primary effectiveness rate of RFA was 98% (65 of 66). Local tumor progression was observed in two (3%) ablation zones of 65 tumors with complete primary effectiveness. The cumulative survival rates at 1, 2, 3, 4, and 5 years were 87, 83, 80, 68, and 55%, respectively. Patients with smaller resected tumors (< or = 5 cm) demonstrated better survival results (P = 0.004). No procedure-related deaths occurred. We observed hepatectomy-related complications in 4 patients (8%, 4 of 53) and an RFA-related complication in 1 patient (2%, 1 of 53). CONCLUSIONS Combined hepatectomy and RFA is an effective and safe treatment modality for multifocal HCCs. Resected tumor size was a significant prognostic predictor of long-term survival.
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Affiliation(s)
- Dongil Choi
- Department of Radiology, Samsung Medical Center, Sungkyunkwan University School of Medicine, 50, Ilwon-Dong, Kangnam-Ku, Seoul, 135-710, Republic of Korea
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Polat KY, Akçay MN, Aydinli B, Erdogan F, Kantarci M, Oztürk G, Peker K. Spontaneous rupture of hepatocellular carcinoma: a case report and review of literature. Int J Clin Pract 2005:103-5. [PMID: 15875641 DOI: 10.1111/j.1742-1241.2004.00257.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Hepatocellular carcinoma (HCC) has a tendency for fatal spontaneous rupture leading to massive haemorrhage. A 64-year-old man presented with sudden, severe epigastric pain for 6 h. Systolic blood pressure was 80/50 mmHg, and pulse rate was 100/min. The patient's history did not reveal any operation or disease up to date. Contrast enhancement-axial computed tomography (CT) scan showed a tumoral lesion with a necrotic centre measuring 6 x 5 cm within 6th segment of the liver and a fluid collection (haemoperitoneum) at the periphery of the liver. At exploratory laparotomy, the liver was found to be cirrhotic, and an actively bleeding tumour confirmed in 6th segment of the liver. The tumour was resected. Post-operative recovery was unremarkable, and the patient was discharged on the 14th post-operative day. Ruptured HCC should be included in the differential diagnosis of non-traumatic intra-abdominal haemorrhage.
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Affiliation(s)
- K Y Polat
- Department of General Surgery, Atatürk University Medical Faculty, Erzurum, Turkey
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Lu DSK, Yu NC, Raman SS, Lassman C, Tong MJ, Britten C, Durazo F, Saab S, Han S, Finn R, Hiatt JR, Busuttil RW. Percutaneous radiofrequency ablation of hepatocellular carcinoma as a bridge to liver transplantation. Hepatology 2005; 41:1130-7. [PMID: 15841454 DOI: 10.1002/hep.20688] [Citation(s) in RCA: 258] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Orthotopic liver transplantation (OLT) can be a definitive treatment for patients with hepatocellular carcinoma (HCC). Prolonged waiting times for cadaveric livers, however, may lead to dropout from the waiting list or worsened post-OLT prognosis as a result of interval tumor progression. Percutaneous radiofrequency ablation (RFA) is widely used for local control of small unresectable HCC, but its pretransplant role remains unclear. We studied the outcome of 52 consecutive patients accepted for OLT bearing 87 HCC nodules and treated with percutaneous RFA. On initial staging, the tumor burden exceeded the Milan criteria in 10 patients. Complete tumor coagulation was observed in 74 of 87 (85.1%) nodules based on postablation imaging. After a mean of 12.7 months (range: 0.3-43.5) on the waiting list, 3 of 52 patients (5.8%) had dropped out due to tumor progression. Forty-one patients had undergone transplantation, with 1- and 3-year post-OLT survival rates of 85% and 76%, respectively. No patient developed HCC recurrence. There were three major complications in 76 RFA procedures (hepatic arterial hemorrhage, small bowel perforation, and liver decompensation salvaged by OLT), without resultant death or dropout. In conclusion, percutaneous RFA is an effective bridge to OLT for patients with compensated liver function and safely accessible tumors. Tumor-related dropout rate and post-OLT outcome compared favorably with published controls of patients with early-stage disease. This can be attributed to the efficacy of RFA in producing local cure or curbing tumor progression during the waiting period.
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Affiliation(s)
- David S K Lu
- Department of Radiology, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA.
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Low MJ. Clinical endocrinology and metabolism. The somatostatin neuroendocrine system: physiology and clinical relevance in gastrointestinal and pancreatic disorders. Best Pract Res Clin Endocrinol Metab 2004; 18:607-22. [PMID: 15533778 DOI: 10.1016/j.beem.2004.08.005] [Citation(s) in RCA: 57] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Somatostatin is produced in enteroendocrine D cells and intrinsic neurons of the stomach, intestines and pancreas. Its physiologic actions are mediated primarily by somatostatin receptors type 2 and 5, and include the inhibition of secretion of most endocrine and exocrine factors. Diseases directly attributable to somatostatin excess or deficiency are rare, although there is a complex pathogenic relationship between persistent Helicobacter pylori infection and reduced somatostatin in chronic gastritis. Abundant somatostatin receptors on many neoplastic and inflammatory cells are the basis for sensitive in vivo imaging with radiolabeled somatostatin analogs and provide a therapeutic target. Current indications for somatostatin therapy include hormone-expressing neuroendocrine tumors, intractable diarrhea and variceal bleeding secondary to portal hypertension. Exciting advances are being made in the development of high-affinity nonpeptide analogs with receptor-subtype selectivity and increased bioavailability. Somatostatin analogs coupled to high-energy radionuclides show promise as novel cytotoxic agents for certain metastatic tumors.
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Affiliation(s)
- Malcolm J Low
- Department of Behavioral Neuroscience, Oregon Health and Science University, 3181 S.W. Sam Jackson Park Road, Portland, OR 97239, USA.
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