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Joseph MM, Aravind SR, George SK, Pillai RK, Mini S, Sreelekha TT. Corrigendum to ``Co-encapsulation of doxorubicin with galactoxyloglucan nanoparticles for intracellular tumor-targeted delivery in murine ascites and solid tumors'' [Translational Oncology 7 (2014), 525-536]. Transl Oncol 2021; 14:101008. [PMID: 33451514 DOI: 10.1016/j.tranon.2020.101008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Affiliation(s)
- Manu M Joseph
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala, India
| | - S R Aravind
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala, India
| | - Suraj K George
- Department of Hematopathology, UT MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | | | - S Mini
- Department of Biochemistry, University of Kerala, Trivandrum, Kerala, India
| | - T T Sreelekha
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala, India.
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Abstract
Multiple myeloma (MM) induced bone lesion is one of the most crippling characteristics, and the MM secreted Dickkopf-1 (DKK1) has been reported to play important role in this pathologic process. However, the underlying regulation mechanisms involved in DKK1 expression are still unclear. In this study, we validated the expression patterns of microRNA (miR) 15a, 34a, 152, and 223 in MM cells and identified that miR-152 was significantly downregulated in the MM group compared with the non-MM group, and that miR-152 level was negatively correlated with the expression of DKK1 in the MM cells. Mechanistic studies showed that manipulating miR-152 artificially in MM cells led to changes in DKK-1 expression, and miR-152 blocked DKK1 transcriptional activity by binding to the 3'UTR of DKK1 mRNA. Importantly, we revealed that MM cells stably expressing miR-152 improved the chemotherapy sensitivity, and counteracted the bone disruption in an intrabone-MM mouse model. Our study contributes better understanding of the regulation mechanism of DKK-1 in MM, and opens up the potential for developing newer therapeutic strategies in the MM treatment.
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Affiliation(s)
- Yinyin Xu
- a Department of Clinical Laboratory ; Affiliated Yongchuan Hospital of Chongqing Medical University ; Chongqing , PR China.,d These authors contributed equally to this study
| | - Bingda Chen
- b Department of Neurology ; People's Hospital of Bishan District ; Bishan , Chongqing , PR China.,d These authors contributed equally to this study
| | - Suraj K George
- c Department of Hematopathology ; The University of Texas MD Anderson Cancer Center ; Houston , TX USA
| | - Beizhong Liu
- a Department of Clinical Laboratory ; Affiliated Yongchuan Hospital of Chongqing Medical University ; Chongqing , PR China
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Murali P, George SK, Ally K, Dipu MT. Effect of L-carnitine supplementation on growth performance, nutrient utilization, and nitrogen balance of broilers fed with animal fat. Vet World 2016; 8:482-6. [PMID: 27047119 PMCID: PMC4774796 DOI: 10.14202/vetworld.2015.482-486] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/28/2015] [Accepted: 03/07/2015] [Indexed: 11/24/2022] Open
Abstract
Aim: This experiment was conducted to evaluate the effect of L-carnitine supplementation on growth performance, nutrient utilization and nitrogen balance in broilers fed with animal fat. Materials and Methods: 80 day-old Cobb commercial broiler chicks were randomly assigned into two dietary treatment groups with four replicates of ten chicks each. The diets were isonitrogenous and isocaloric. The birds in both the control (T1) and treatment group (T2) were fed with a diet having 5% animal fat, while the treatment group (T2) was supplemented with 900 mg of L-carnitine. The birds were fed with standard broiler starter ration up to 4 weeks of age and finisher ration up to 6 weeks of age. Results: The average body weight (g), cumulative feed intake (g) and cumulative feed conversion ratio belonging to groups T1 and T2 at 6th week of age were 2091.25 and 2151.11, 3976.49 and 4171.68, 1.97 and 1.96 respectively. The percentage availability of the nutrients of two experimental rations T1 and T2 was 68.23 and 68.00 for dry matter, 58.72 and 55.98 for crude protein, 73.85 and 71.35 for ether extract, 34.19 and 33.86 for crude fiber, 79.18 and 79.59 for nitrogen free extract, 70.24 and 70.03 for energy efficiency and nitrogen balance (g/day) were 2.35 and 2.39, respectively. Conclusion: This study suggests that the supplementation of 900 mg L-carnitine in diet with added animal fat had no effect on growth performance, nutrient utilization, and nitrogen balance of broilers.
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Affiliation(s)
- P Murali
- Department of Animal Nutrition, College of Veterinary and Animal Sciences, Mannuthy, Thrissur - 680 651, Kerala, India
| | - S K George
- Department of Animal Nutrition, College of Veterinary and Animal Sciences, Mannuthy, Thrissur - 680 651, Kerala, India
| | - K Ally
- Department of Animal Nutrition, College of Veterinary and Animal Sciences, Mannuthy, Thrissur - 680 651, Kerala, India
| | - M T Dipu
- Department of Animal Nutrition, College of Veterinary and Animal Sciences, Mannuthy, Thrissur - 680 651, Kerala, India
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Aravind SR, Joseph MM, George SK, Dileep KV, Varghese S, Rose-James A, Balaram P, Sadasivan C, Sreelekha TT. TRAIL-based tumor sensitizing galactoxyloglucan, a novel entity for targeting apoptotic machinery. Int J Biochem Cell Biol 2014; 59:153-66. [PMID: 25541375 DOI: 10.1016/j.biocel.2014.11.019] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2014] [Revised: 11/19/2014] [Accepted: 11/22/2014] [Indexed: 01/08/2023]
Abstract
Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is an attractive target for cancer therapy due to its ability to selectively induce apoptosis in cancer cells, without causing significant toxicity in normal tissues. We previously reported that galactoxyloglucan (PST001) possesses significant antitumor and immunomodulatory properties. However, the exact mechanism in mediating this anticancer effect is unknown. This study, for the first time, indicated that PST001 sensitizes non-small cell lung cancer (A549) and nasopharyngeal (KB) cells to TRAIL-mediated apoptosis. In vitro studies suggested that PST001 induced apoptosis primarily via death receptors and predominantly activated caspases belonging to the extrinsic apoptotic cascade. Microarray profiling of PST001 treated A549 and KB cells showed the suppression of survivin (BIRC5) and anti-apoptotic Bcl-2, as well as increased cytochrome C. TaqMan low density array analysis of A549 cells also confirmed that the induction of apoptosis by the polysaccharide occurred through the TRAIL-DR4/DR5 pathways. This was finally confirmed by in silico analysis, which revealed that PST001 binds to TRAIL-DR4/DR5 complexes more strongly than TNF and Fas ligand-receptor complexes. In summary, our results suggest the potential of PST001 to be developed as an anticancer agent that not only preserves innate biological activity of TRAIL, but also sensitizes cancer cells to TRAIL-mediated apoptosis.
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Affiliation(s)
- S R Aravind
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala 695011, India
| | - Manu M Joseph
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala 695011, India
| | - Suraj K George
- Department of Hematopathology, UT MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | - K V Dileep
- Department of Biotechnology and Microbiology and Inter-University Centre for Bioscience, Kannur University, Thalassery Campus, Palayad, Kerala 670661, India
| | - Sheeja Varghese
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala 695011, India
| | - Alphy Rose-James
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala 695011, India
| | - Prabha Balaram
- Quest International University, Perak, No. 227, Plaza Teh Teng Seng-level 2, Jalan Raja Permaisuri Bainum, 30250 Ipoh, Perak, Malaysia
| | - C Sadasivan
- Department of Biotechnology and Microbiology and Inter-University Centre for Bioscience, Kannur University, Thalassery Campus, Palayad, Kerala 670661, India
| | - T T Sreelekha
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala 695011, India.
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Zhu Z, Huang P, Chong Y, George SK, Wen B, Han N, Liu Z, Kang L, Lin N. Nucleus pulposus cells derived IGF-1 and MCP-1 enhance osteoclastogenesis and vertebrae disruption in lumbar disc herniation. Int J Clin Exp Pathol 2014; 7:8520-8531. [PMID: 25674216 PMCID: PMC4313999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 12/01/2014] [Indexed: 06/04/2023]
Abstract
STUDY DESIGN Chronic strained lumbar disc herniation (LDH) cases were classified into bulging LDH, herniated LDH and prolapse LDH types according to imaging examination, and vertebrae disruptions were evaluated. Cytokines derived from the nucleus pulposus cells were detected, and their effects on osteoclastogenesis, as well as the mechanisms involved, were studied via an in vitro osteoclast differentiation system. OBJECTIVE To clarify the mechanisms of lumbar vertebrae resorption induced by lumbar herniation. SUMMARY AND BACKGROUND DATA Chronic strained lumbar disc herniation induced vertebrae erosion exacerbates quality of patients' life and clinical outcome. Although nucleus pulposus cells derived cytokines were reported to play an important role in this pathogenesis, the fundamental mechanisms underlying this process are still unclear. METHODS Chronic strained lumbar disc herniation patients were diagnosed with CT scan and T2-weighted magnetic resonance imaging. RNA was extracted from 192 surgical specimens of the herniated lumbar disc and 29 surgical excisions of the lumbar disc from spinal injury patients. The expressions of osteoclastogenesis related cytokines and chemokines were examined using real time PCR. Monocytes were induced into osteoclast with M-CSF and RANKL in vitro, while the IGF-1 and MCP-1 were added into the differentiation procedure in order to evaluate the effects and explore the molecular mechanisms. RESULTS Vertebrae erosion had a positive relationship with lumbar disc herniation severity types. In all of the osteoclastogenesis related cytokines, the IGF-1 and MCP-1 were the most highly expressed in the nucleus pulposus cells. IGF-1 enhances activation of NF-kB signaling directly, but MCP-1 upregulated the expression of RANK, so that enhanced cellular sensitivity to RANKL resulted in increasing osteoclastogenesis and activity. CONCLUSION Lumbar herniation induced overexpression of IGF-1 and MCP-1 in nucleus pulposus cells aggravated vertebral erosions. Hence, this study suggests that targeting osteoclastogenesis related cytokines has potential clinical significance in the treatment of lumbar disc herniation patients.
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Affiliation(s)
- Zhongjiao Zhu
- Department of Orthopedics, Tenzhou Central People’s HosipitalTenzhou 277500, Shandong, China
- Department of Orthopedics, Shandong University Qilu HospitalJinan, Shandong, 250012, China
| | - Peng Huang
- Department of Emergency, Tengzhou Hospital of Traditional Chinese MedicineTengzhou 277500, Shandong, China
| | - Yanxue Chong
- Department of Orthopedics, Tenzhou Central People’s HosipitalTenzhou 277500, Shandong, China
| | - Suraj K George
- Department of Hematopathology, The University of Texas MD Anderson Cancer CenterHouston 77054, Texas, USA
| | - Bingtao Wen
- Department of Orthopedics, Tenzhou Central People’s HosipitalTenzhou 277500, Shandong, China
| | - Na Han
- Department of Orthopedics, Peking University People’s HospitalBeijing 100029, China
| | - Zhiqiang Liu
- Division of Medicine, Center for Cancer Immunology Research, The University of Texas M D Anderson Cancer CenterHouston 77054, Texas USA
| | - Lixin Kang
- Department of Orthopedics, Tenzhou Central People’s HosipitalTenzhou 277500, Shandong, China
| | - Nie Lin
- Department of Orthopedics, Shandong University Qilu HospitalJinan, Shandong, 250012, China
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Joseph MM, Aravind SR, George SK, Pillai KR, Mini S, Sreelekha TT. Galactoxyloglucan-Modified Nanocarriers of Doxorubicin for Improved Tumor-Targeted Drug Delivery with Minimal Toxicity. J Biomed Nanotechnol 2014; 10:3253-68. [DOI: 10.1166/jbn.2014.1957] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Joseph MM, Aravind S, George SK, Pillai RK, Mini S, Sreelekha T. Co-encapsulation of Doxorubicin with galactoxyloglucan nanoparticles for intracellular tumor-targeted delivery in murine ascites and solid tumors. Transl Oncol 2014; 7:525-36. [PMID: 25389448 PMCID: PMC4225659 DOI: 10.1016/j.tranon.2014.07.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2014] [Revised: 07/14/2014] [Accepted: 07/18/2014] [Indexed: 12/22/2022] Open
Abstract
Doxorubicin (Dox) treatment is limited by severe toxicity and frequent episodes of treatment failure. To minimize adverse events and improve drug delivery efficiently and specifically in cancer cells, encapsulation of Dox with naturally obtained galactoxyloglucan polysaccharide (PST001), isolated from Tamarindus indica was attempted. Thus formed PST-Dox nanoparticles induced apoptosis and exhibited significant cytotoxicity in murine ascites cell lines, Dalton's lymphoma ascites and Ehrlich's ascites carcinoma. The mechanism contributing to the augmented cytotoxicity of nanoconjugates at lower doses was validated by measuring the Dox intracellular uptake in human colon, leukemic and breast cancer cell lines. PST-Dox nanoparticles showed rapid internalization of Dox into cancer cells within a short period of incubation. Further, in vivo efficacy was tested in comparison to the parent counterparts - PST001 and Dox, in ascites and solid tumor syngraft mice models. Treatment of ascites tumors with PST-Dox nanoparticles significantly reduced the tumor volume, viable tumor cell count, and increased survival and percentage life span in the early, established and prophylactic phases of the disease. Administration of nanoparticles through intratumoral route delivered more robust antitumor response than the intraperitoneal route in solid malignancies. Thus, the results indicate that PST-Dox nanoparticles have greater potential compared to the Dox as targeted drug delivery nanocarriers for loco regional cancer chemotherapy applications.
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Affiliation(s)
- Manu M. Joseph
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala, India
| | - S.R. Aravind
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala, India
| | - Suraj K. George
- Department of Hematopathology, UT MD Anderson Cancer Center, 1515 Holcombe Blvd, Houston, TX 77030, USA
| | | | - S. Mini
- Department of Biochemistry, University of Kerala, Trivandrum, Kerala, India
| | - T.T. Sreelekha
- Laboratory of Biopharmaceuticals and Nanomedicine, Division of Cancer Research, Regional Cancer Centre, Trivandrum, Kerala, India
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Zhang Q, Jing W, Ouyang J, Zeng H, George SK, Liu Z. Six cases of aggressive natural killer-cell leukemia in a Chinese population. Int J Clin Exp Pathol 2014; 7:3423-3431. [PMID: 25031771 PMCID: PMC4097262] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 05/27/2014] [Indexed: 06/03/2023]
Abstract
Aggressive natural killer cell leukemia (ANKL) is a rare hematological malignancy that is particularly common among the Asian population. In the current study, we retrospectively evaluated six Chinese ANKL patients, including five males and one female, with a median age of 42 years (range 22 to 50 years). A number of unusual pathogenic manifestations were found in these ANKL patients, such as isolated extraocular muscle involvement, and hemophagocytic syndrome (HPS) with acute renal failure and multiple cavity effusion. Four of the patients died between two and six months after the diagnosis; however, there were two ANKL cases whose clinical behavior differed from the typical clinical course. One survived for over 30 months after splenectomy and chemotherapy treatment, and another ANKL case derived from chronic lymphoproliferative disorders of NK-cells (CLPD-NK) was treated with allogeneic bone marrow transplant (allo-BMT) and survived over 18 months. In conclusion, four cases experienced an aggressive clinical course whereas two demonstrated an indolent manifestation of their disease. New therapeutic regimens including allo-BMT should be optimized in order to improve outcomes of this disease.
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Affiliation(s)
- Qiguo Zhang
- Department of Hematology, Nanjing University Drum Tower HospitalNanjing 210008, Jiangsu, China
| | - Wang Jing
- Department of Hematology, Nanjing University Drum Tower HospitalNanjing 210008, Jiangsu, China
| | - Jian Ouyang
- Department of Hematology, Nanjing University Drum Tower HospitalNanjing 210008, Jiangsu, China
| | - Hui Zeng
- Department of Hematology, Nanjing University Drum Tower HospitalNanjing 210008, Jiangsu, China
| | - Suraj K George
- Department of Hematopathology, University of Texas MD Anderson Cancer CenterHouston, Texas 77054, USA
| | - Zhiqiang Liu
- Department of Lymphoma and Myeloma, University of Texas MD Anderson Cancer CenterHouston, Texas 77054, USA
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Radhakrishnan R, George SK, Kumar S, Balaram P. Maintenance of Immunological Homeostasis byIndukantha Ghrithain Patients with Recurrent Upper Respiratory Tract Infections-A Pilot Study. Phytother Res 2014; 28:1252-9. [DOI: 10.1002/ptr.5132] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2013] [Revised: 01/03/2014] [Accepted: 01/22/2014] [Indexed: 01/03/2023]
Affiliation(s)
- Rajesh Radhakrishnan
- Laboratory of Tumor Immunology and Functional Genomics, Division of Cancer Research; Regional Cancer Centre; Thiruvananthapuram Kerala India
| | - Suraj K. George
- Laboratory of Tumor Immunology and Functional Genomics, Division of Cancer Research; Regional Cancer Centre; Thiruvananthapuram Kerala India
- Department of Hematopathology; University of Texas MD Anderson Cancer Center; Houston TX 77030 USA
| | - Sunil Kumar
- Laboratory of Tumor Immunology and Functional Genomics, Division of Cancer Research; Regional Cancer Centre; Thiruvananthapuram Kerala India
| | - Prabha Balaram
- Laboratory of Tumor Immunology and Functional Genomics, Division of Cancer Research; Regional Cancer Centre; Thiruvananthapuram Kerala India
- Faculty of Integrated Sciences and Technology; QUEST International University; 30250 Ipoh Perak Malaysia
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George SK, Radhakrishnan R, Kumar SS, Sreelekha TT, Balaram P. Chemopreventive efficacy of Aegle marmelos on murine transplantable tumors. Integr Cancer Ther 2013; 13:68-78. [PMID: 23729467 DOI: 10.1177/1534735413490234] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Emerging trends for cancer chemotherapy show promising developments with the better understanding of molecules delivering more potent and powerful capabilities. But these are severely limited because of increased side effects and higher probability of tumor recurrence. In this scenario, putative exploration of the indigenous and untapped resources modulating immune system to deliver adequate but potent chemopreventive effects appeals considerable interest. However, these require rigorous scientific validation with regard to potency compared with the existing drugs. Aegle marmelos (Linnaeus) Correa (family Rutaceae), a plant component of polyherbal formulation, Indukantha Ghritha, is known for its widespread medicinal values. But the chemopreventive potential has not been explored in comparison to existing anticancer agents. Our attempt contributes the scientific evidence for beneficial immunoprophylactic and antitumor functions in mice challenged with ascites tumors, Dalton's lymphoma ascites, and Ehrlich's ascites carcinoma either alone or in combination with cyclophosphamide and 5-fluorouracil. Specifically, the petroleum ether extracts of this plant (AM(PE)) prophylactically activated a cascade of host defense mechanisms by stimulating or restoring total white blood cell count, macrophage phagocytosis, hematopoiesis, lymphocyte proliferation and functions (CD4+ and CD8+) either naturally or under conditions of impaired immunity like in ascites tumor or during standard agent chemotherapy. Overall, AM(PE) also elicited strong antitumor effects by increasing median survival time and life span, while reducing murine ascites tumor volume and viable tumor counts on par with cyclophosphamide and 5-fluorouracil especially when administered prophylactically. This study also identified 2 putative components, xanthorrhizol and marmelosin, which could be imparting the immunoprophylactic and antitumor effects in transplantable tumor models. Thus, our attempts provide sufficient proof to warrant further to test this drug in higher animal models or in patients with high risk for tumor recurrence and/or immunocompromised diseases.
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Affiliation(s)
- Suraj K George
- Regional Cancer Centre, Thiruvananthapuram, Kerala, India
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George SK, Dipu MT, Mehra UR, Singh P, Verma AK, Ramgaokar JS. Improved HPLC method for the simultaneous determination of allantoin, uric acid and creatinine in cattle urine. J Chromatogr B Analyt Technol Biomed Life Sci 2006; 832:134-7. [PMID: 16298557 DOI: 10.1016/j.jchromb.2005.10.051] [Citation(s) in RCA: 103] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2005] [Revised: 09/21/2005] [Accepted: 10/25/2005] [Indexed: 10/25/2022]
Abstract
An HPLC procedure developed for the rapid and simultaneous determination of purine derivatives (PD) in ruminants' urine was investigated, since the adoption of a single method for the simultaneous detection of PD and creatinine was not carried out due to elution of polar co-extractives and also due to overlapping of the peaks of allantoin and creatinine. The experimental conditions chosen in the present study avoid the presence of chemically competitive compounds and afford a good separation of the peaks of allantoin and creatinine. The recoveries of the standard compounds added to urine samples were 94-104%. This method can be proposed as a possible reference method for the estimation of allantoin, uric acid and creatinine in cattle urine.
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Affiliation(s)
- S K George
- Animal Nutrition Division, Indian Veterinary Research Institute, Izatnagar 243 122, UP, India.
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George SK, Schwientek T, Holm B, Reis CA, Clausen H, Kihlberg J. Chemoenzymatic synthesis of sialylated glycopeptides derived from mucins and T-cell stimulating peptides. J Am Chem Soc 2001; 123:11117-25. [PMID: 11697954 DOI: 10.1021/ja015570t] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The Tn, T, sialyl-Tn, and 2,3-sialyl-T antigens are tumor-associated carbohydrate antigens expressed on mucins in epithelial cancers, such as those affecting the breast, ovary, stomach, and colon. Glycopeptides carrying these antigens are of interest for development of cancer vaccines and a short, chemoenzymatic strategy for their synthesis is reported. Building blocks corresponding to the Tn (GalNAc alpha-Ser/Thr) and T [Gal beta(1-->3)GalNAc alpha-Ser/Thr] antigens, which are relatively easy to obtain by chemical synthesis, were prepared and then used in the synthesis of glycopeptides on the solid phase. Introduction of sialic acid to give the sialyl-Tn [Neu5Ac alpha(2-->6)GalNAc alpha-Ser/Thr] and 2,3-sialyl-T [Neu5Ac alpha(2-->3)Gal beta(1-->3)GalNAc alpha-Ser/Thr] antigens is difficult when performed chemically at the building block level. Sialylation was therefore carried out with recombinant sialyltransferases in solution after cleavage of the Tn and T glycopeptides from the solid phase. In the same manner, the core 2 trisaccharide [Gal beta 1-->3(GlcNAc beta 1-->6)GalNAc] was incorporated in glycopeptides containing the T antigen by using a recombinant N-acetylglucosaminyltransferase. The outlined chemoenzymatic approach was applied to glycopeptides from the tandem repeat domain of the mucin MUC1, as well as to neoglycosylated derivatives of a T cell stimulating viral peptide.
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Affiliation(s)
- S K George
- Department of Organic Chemistry, Umeå University, SE-901 87 Umeå, Sweden
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Abstract
Coronary artery disease is highly prevalent in patients with end-stage renal disease, and accounts for much of their observed morbidity and mortality. Despite this, diagnosing myocardial disease in this population remains problematic, because many patients present with abnormal baseline electrocardiograms, frequently compounded by silent or atypical symptoms. Conventionally used enzymatic markers of cardiac injury have not resolved this dilemma because of their poor specificity in end-stage renal disease. In particular, nonspecific elevations in creatinine kinase-muscle brain enzyme, a widely accepted marker of cardiac injury, have been consistently observed in the absence of other demonstrable evidence for cardiac injury. Recently, the cardiac troponins (troponin I and troponin T) have emerged as more sensitive markers for cardiac ischemia, facilitating rapid bedside diagnosis and early risk stratification. Unfortunately, cardiac troponin T shows poor specificity in end-stage renal disease, possibly because of variable expression in extracardiac tissues. On the other hand, troponin I consistently maintains a high sensitivity and specificity, and is the most sensitive marker for ischemic heart disease in this patient population.
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Affiliation(s)
- S K George
- Renal Division, Brigham & Women's Hospital, Harvard Medical School, Boston, Massachusetts 02115, USA
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Bush KT, George SK, Zhang PL, Nigam SK. Pretreatment with inducers of ER molecular chaperones protects epithelial cells subjected to ATP depletion. Am J Physiol 1999; 277:F211-8. [PMID: 10444575 DOI: 10.1152/ajprenal.1999.277.2.f211] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
We have investigated the potential cytoprotective role of endoplasmic reticulum (ER) molecular chaperones in a cultured cell model of renal ischemia. Madin-Darby canine kidney (MDCK) cells were pretreated with tunicamycin (an inducer of ER but not cytosolic molecular chaperones) for 12-16 h, followed by 6 h of ATP depletion. A rapid and severe depletion of cellular ATP was noted in both control and tunicamycin-treated cells. Trypan blue exclusion assays indicated that pretreatment of MDCK cells with tunicamycin reduced ATP depletion-induced cell damage by approximately 80% compared with nonpretreated controls. This apparent cytoprotective effect was also found following pretreatment with another inducer of ER molecular chaperones (i.e., A23187). For example, A23187 was found to reduce lactate dehydrogenase release by approximately 50% compared with untreated controls, whereas E-64, a cysteine protease inhibitor which may affect degradation of some proteins in the ER, had little or no effect on cell injury. Moreover, a fluorescent assay confirmed the marked reduction in cell damage following ATP depletion (up to 80% reduction in tunicamycin-pretreated cells). Together, these findings are consistent with the notion that induction of ER molecular chaperones leads to the acquisition of cytoprotection in the face of ATP depletion. However, inhibition of protein translation by cycloheximide was found to only partially attenuate the observed cytoprotective effect, raising the possibility that other, as yet to be identified, nonprotein synthesis-dependent mechanisms may also play a role in the observed cytoprotection.
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Affiliation(s)
- K T Bush
- Renal Division, Department of Medicine, Brigham and Women's Hospital and Harvard Medical School, Boston, Massachusetts 02115, USA
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Abstract
During August 1989, the urine of 5010 women of childbearing-age in Alabama was screened for marijuana, cocaine, opiates, amphetamines, and barbiturates. The data base consisted of 2970 pregnant women, 374 of whom were at high risk, and 2019 nonpregnant women. Our findings included the following information: (1) The statewide prevalence of positive screens for any drugs tested was 12.9% for all women (11.0% for those who were pregnant and 15.6% for those who were not pregnant). (2) There was no difference between urban and rural groups for any drugs tested. (3) Positive marijuana screens were increased among white and nonpregnant women (p less than 0.01). (4) Positive cocaine screens were increased among black and single women (p less than 0.01). (5) More screens were positive in women older than age 20 (p less than 0.01). (6) There was no difference between pregnant and nonpregnant women for positive cocaine screens. (7) No difference existed among the trimesters of pregnancy for positive cocaine screens. (8) Positive screens for marijuana were more frequent in the first trimester of pregnancy than in the second trimester (p = 0.02) or the third trimester (p = 0.001). (9) There was no difference between high-risk and low-risk maternity patients for any drugs tested.
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Affiliation(s)
- S K George
- Department of Public Health, University of Alabama, Birmingham
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George SK, Xu YH, Benson LA, Pratsch L, Peters R, Ihler GM. Cytochrome b5 and a recombinant protein containing the cytochrome b5 hydrophobic domain spontaneously associate with the plasma membranes of cells. Biochim Biophys Acta 1991; 1066:131-43. [PMID: 1906748 DOI: 10.1016/0005-2736(91)90179-c] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Both cytochrome b5, isolated from rabbit liver microsomes, and LacZ:HP, a recombinant protein consisting of enzymatically active Escherichia coli beta-galactosidase coupled to the C-terminal membrane-anchoring hydrophobic domain of cytochrome b5, were shown to spontaneously associate with the plasma membranes of erythrocytes and 3T3 cells. Association was promoted by low pH values, but proceeded satisfactorily over several hours at physiological pH and temperature. About 150,000 cytochrome b5 molecules or 100,000 LacZ:HP molecules could be associated per erythrocyte. These proteins were not removed from the membrane by extensive washing, even at high ionic strength. After incubation with fluorescently labeled cytochrome b5 or LacZ:HP, cells displayed fluorescent membranes. The lateral mobility of fluorescently labeled cytochrome b5 and LacZ:HP was measured by photo-bleaching techniques. In the plasma membrane of erythrocytes and 3T3 cells, the apparent lateral diffusion coefficient D ranged from 1.0.10(-9) to 8.10(-9) cm2 s-1 with a mobile fraction M between 0.4 and 0.6. The lateral mobility of these proteins closely resembled that reported for lipid-anchored proteins and was much higher than that reported for Band 3, an erythrocyte membrane-spanning protein with a large cytoplasmic domain. These results suggest that the hydrophobic domain of cytochrome b5 could be employed as a universal, laterally mobile membrane anchor to associate a variety of diagnostically and therapeutically useful recombinant proteins with cells.
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Affiliation(s)
- S K George
- Department of Medical Biochemistry and Genetics, Texas A&M College of Medicine, College Station
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George SK, Najera L, Sandoval R, Ihler GM. Beta-galactosidase fused to the hydrophobic domain of cytochrome b5 spontaneously associates with liposomes. Biochim Biophys Acta 1991; 1061:26-32. [PMID: 1899801 DOI: 10.1016/0005-2736(91)90264-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Since liver microsomal cytochrome b5 spontaneously associates with liposomes and membranes by means of its C-terminal hydrophobic domain (HP), chimeric proteins containing HP prepared by genetic fusion might also spontaneously associate with liposomes or cellular membranes. Synthetic DNA corresponding to the hydrophobic domain of cytochrome b5 was enzymatically fused in-frame to cloned DNA corresponding to the C-terminus of the Escherichia coli enzyme, beta-galactosidase. This protein, LacZ:HP, synthesized in E. coli and purified from a crude E. coli membrane extract, was shown to spontaneously associated with liposomes, as does cytochrome b5. Association is rapid and stable in the presence of salt and high pH and the fusion protein behaves as an integral membrane protein. LacZ:HP can be readily and extensively purified from crude extracts by association with liposomes and this procedure may provide a convenient purification scheme for proteins not otherwise readily purified, for example polypeptides from cloned gene fragments to be used for antibody production. These hybrid proteins may represent a new potentially useful class of polypeptides capable of hydrophobic interactions with membranes.
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Affiliation(s)
- S K George
- Department of Medical Biochemistry and Genetics, Texas A & M College of Medicine, College Station 77843
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18
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George SK, Najera L, Sandoval RP, Countryman C, Davis RW, Ihler GM. The hydrophobic domain of cytochrome b5 is capable of anchoring beta-galactosidase in Escherichia coli membranes. J Bacteriol 1989; 171:4569-76. [PMID: 2504691 PMCID: PMC210252 DOI: 10.1128/jb.171.9.4569-4576.1989] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Cytochrome b5 is inserted posttranslationally into membranes in vivo and spontaneously into liposomes in vitro by a short carboxyl-terminal hydrophobic membrane-anchoring sequence. DNA corresponding to this hydrophobic sequence has been synthesized, and two gene fusions with the Escherichia coli enzyme beta-galactosidase have been constructed by locating the hydrophobic domain in one case at the EcoRI site near the C terminus and in the other at the normal C terminus of the enzyme. The latter fusion protein was enzymatically active, having approximately 50% of the specific activity of beta-galactosidase, and cells expressing this protein grew normally with lactose as the sole carbon source. Both fusion proteins were localized to the E. coli inner membrane, converting beta-galactosidase from a cytoplasmic enzyme to a membrane-associated enzyme. The hydrophobic domain of cytochrome b5 therefore contains the information required to target polypeptides containing this domain to the membrane. Use of the cytochrome b5 hydrophobic peptide, either alone or in conjunction with other localizing sequences such as signal sequences, provides a general procedure for associating proteins with membranes. Polypeptides bearing this hydrophobic peptide may have considerable use as pharmaceuticals when associated with liposomes or cellular membranes.
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Affiliation(s)
- S K George
- Department of Medical Biochemistry and Genetics, Texas A&M College of Medicine, College Station 77843-1114
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Ghiglione M, Blazquez E, Uttenthal LO, de Diego JG, Alvarez E, George SK, Bloom SR. Glucagon-like peptide-1 does not have a role in hepatic carbohydrate metabolism. Diabetologia 1985; 28:920-1. [PMID: 3005098 DOI: 10.1007/bf00703137] [Citation(s) in RCA: 32] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Glucagon-like peptide-1 does not have specific, high-affinity receptors on rat liver membranes, does not displace glucagon from glucagon receptors on these membranes and does not stimulate the production of cyclic AMP by isolated rat hepatocytes. In the presence of glucagon, high concentrations of glucagon-like peptide-1 do not significantly alter the production of cyclic AMP. Thus, glucagon-like peptide-1 appears unlikely to have a direct action on hepatic carbohydrate metabolism.
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Abstract
Molecular forms of the glucagon-like peptides (GLP) encoded by the human preproglucagon gene were analysed by chromatography combined with specific radioimmunoassays to the synthetic peptides. Whereas extracts of human pancreas and a glucagonoma contained a large proglucagon cleavage product possessing both GLP-1 and GLP-2 immunoreactivities, extracts of human intestine contained products corresponding to free GLP-1 and a small amount of chromatographically distinct GLP-2 immunoreactivity. It is concluded that post-translational processing of proglucagon differs in pancreas and intestine, so that the C-terminal portion of the molecule is cleaved to liberate free GLP-1 in the intestine. Further processing or degradation results in loss especially of GLP-2 immunoreactivity.
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Uttenthal LO, Ghiglione M, George SK, Bishop AE, Polak JM, Bloom SR. Molecular forms of glucagon-like peptide-1 in human pancreas and glucagonomas. J Clin Endocrinol Metab 1985; 61:472-9. [PMID: 2991321 DOI: 10.1210/jcem-61-3-472] [Citation(s) in RCA: 36] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The structure of human preproglucagon, as deduced from nucleotide sequencing of the preproglucagon gene, contains two glucagon-like peptides (GLP-1 and GLP-2) in the portion C-terminal to glucagon. A rabbit antiserum was raised against synthetic GLP-1-(1-19) which had 20% cross-reactivity with synthetic GLP-1 and des-Gly37-GLP-1 amide, two possible forms of the GLP-1 whole molecule, but no significant cross-reactivity with glucagon or other pancreatic peptides. Immunocytochemistry revealed that the distribution of GLP-1-(1-19) immunoreactivity followed that of glucagon-like immunoreactivity in the normal human pancreas and in two human glucagon-secreting pancreatic tumors. Chromatography of human pancreas extracts on Sephadex G-50 gave peaks of cross-reactivity at Kav values of 0.06-0.16, 0.34-0.39, 0.54-0.58 (the elution position of synthetic GLP-1), and 0.64-0.70. The concentration of immunoreactivity in the Kav 0.54-0.58 peak measured by RIA using GLP-1 or des-Gly37-GLP-1 amide as standard was 94 +/- 7 pmol/g (mean +/- SEM), while the total pancreatic glucagon content was 4.8 +/- 0.8 nmol/g. One extract of a human glucagon-secreting pancreatic tumor contained a prominent peak of GLP-1-(1-19) peptide cross-reactivity with properties identical to those of GLP-1 or des-Gly37-GLP-1 amide on gel filtration and reverse phase high pressure liquid chromatography, but another tumor contained a preponderance of cross-reactive forms of greater molecular size. Pretreatment plasma from three patients with radiological and biochemical evidence of glucagon-secreting tumors contained a peak of cross-reactivity with the chromatographic properties of intact GLP-1. The low concentrations of intact GLP-1 in normal pancreas compared with pancreatic glucagon concentrations suggest that the majority of the proglucagon is cleaved in a manner that does not produce GLP-1, as defined by its delimiting pairs of basic amino acid residues.
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Abstract
Although glucagon-like peptide-1 has the appearance of a glucagon-homologue that may be co-secreted with glucagon, synthetic glucagon-like peptide-1-(1-37) does not significantly affect plasma glucose and insulin concentrations when administered at high doses (100 and 400 micrograms) to cortisone-pretreated rabbits. This synthetic preparation thus lacks the primary metabolic effect of glucagon at the doses tested. An intra- or extra-pancreatic role of glucagon-like peptide-1 has yet to be discovered.
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Ghatei MA, George SK, Major JH, Carlei F, Polak JM, Bloom SR. Bombesin-like immunoreactivity in the pancreas of man and other mammalian species. Experientia 1984; 40:884-6. [PMID: 6381087 DOI: 10.1007/bf01952009] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Bombesin-like immunoreactivity has been measured in pancreatic tissues of man (12.4 +/- 1.2 pmol/g), pig (15.8 +/- 3.2), calf (4.3 +/- 0.9), rat (8.5 +/- 1.2) and guinea-pig (2.8 +/- 0.6) by a specific radioimmunoassay. Gel filtration of the pancreatic extracts revealed 2 major immunoreactive peaks: the earlier peak was eluted in the position of porcine gastrin-releasing peptide, and the later peak was eluted just after the amphibian bombesin standard. Immunocytochemistry demonstrated the presence of bombesin-like immunoreactivity in nerves in the rat pancreas, particularly in the exocrine pancreas, and occasionally in the peri-insular spaces. Isolated rat pancreatic islets were found to contain small quantities of bombesin-like immunoreactivity (0.037 +/- 0.003 fmol/islet) suggesting that mammalian bombesin-like peptides may be involved in the regulation of endocrine as well as exocrine pancreatic secretion.
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