• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6215-6223
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• 2015

Tyrosine phosphorylation plays an important role in regulating human physiological and pathological processes. Functional stabilization of tyrosine phosphorylation largely contributes to the balanced, coordinated regulation of protein tyrosine kinases (PTKs) and protein tyrosine phosphatases (PTPs). Research has revealed PTPs play an important suppressive role in carcinogenesis and progression by reversing oncoprotein functions. Receptor-type protein tyrosine phosphatase O (PTPRO) as one member of the PTPs family has also been identified to have some roles in tumor development. Some reports have shown PTPRO over-expression in tumors can not only inhibit the frequency of tumor cell division and induce tumor cell death, but also suppress migration. However, the tumor-suppression mechanisms are very complex and understanding is incomplete, which in some degree blocks the further development of PTPRO. Hence, in order to resolve this problem, we here have summarized research findings to draw meaningful conclusions. We found tumor-suppression mechanisms of PTPRO to be diverse, such as controlling G0/G1 of the tumor cell proliferation cycle, inhibiting substrate phosphorylation, down-regulating transcription activators and other activities. In clinical anticancer efforts, expression level of PTPRO in tumors can not only serve as a biomarker to monitor the prognosis of patients, but act as an epigenetic biomarker for noninvasive diagnosis. In addition, the re-activation of PTPRO in tumor tissues, not only can induce tumor volume reduction, but also enhance the susceptibility to chemotherapy drugs. So, we can propose that these research findings of PTPRO will not only support new study ideas and directions for other tumor-suppressors, importantly, but also supply a theoretical basis for researching new molecular targeting agents in the future.

• Journal of Haehwa Medicine
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• v.10 no.2
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• pp.1-10
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• 2002

In review of "invigorating spleen and supplementing qi" of clinical and experimental studies on malignant tumor, we obtained the conclusions as follows 1. Asthenic splenic qi is an important factor in mutation, occurrence and development of tumor. 2. The anti-tumor mechanism of "invigorating spleen and supplementing qi" is improvement of immune suveillance, controling cell proliferating period and enhancing body metabolism. 3. "Invigorating spleen and supplementing qi" is often used with "nourishing kidney" or "expelling pathogen" for treating cnacer. 4. In experimental studies, "invigorating spleen and supplementing qi" has effects on inhibiting occurrence and development of tumor, protecting mutation, inhibiting recurrence and metastasis, immune activity, enhancing metabolism, promoting bone marrow hemopoietic cell proliferation, increasing anti-tumor effect and protecting normal cells. 5. In clinical studies, "invigorating spleen and supplementing qi" has effects on prolonging the survival period of cancer patients, improving clinical symptoms and quality of life of cancer patients, degrading the side effects of western therapie(operation, chemotherapy and radiotherapy). 6. "Invigorating spleen and supplementing qi" is an extensive discipline of syndrome differentiation used to inhibit occurence, development, recurrence and metastasis.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7431-7434
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• 2015

As an important component of innate immune system, neutrophil has been involved in many other physiological processes, including tumor-related diseases. In 2004, the phenomenon of NETs was reported for the first time. Extracellular decondensed chromatin, released from activated neutrophils, forms a network structure, which is NETs. This review focuses on the function of NETs in tumor cell proliferation, metastasis, and tumor-associated thrombosis; it also explores the application of NETs specific markers in the diagnosis of pre-thrombotic state and tumor associated diseases; it also explores NETs inhibitor for the treatment of tumor-related diseases. In view of the rapid development of NETs, it may provide new therapeutic targets for tumor-associated thrombosis, and even tumor itself.

• Nutritional Sciences
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• v.9 no.3
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• pp.212-226
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• 2006

The involvement of arachidonic acid (AA) metabolizing enzyme, lipoxygenase (LOX), in the development of particular tumors in humans has gradually been acknowledged and LOX has emerged as a novel target to prevent or treat human cancers. In the mouse skin carcinogenesis model, which provides an excellent model to study multistage nature of human cancer development, many studies have shown that some of the LOXs are constitutively upregulated in their expression. Moreover, application of LOX inhibitors effectively reduced tumor burdens, which implicates the involvement of LOX in mouse skin tumor development as well. 8S-LOX is a recently cloned LOX, which is specifically expressed in mouse skin after 12-O-tetradecanoyl-phorbol-13-acetate (TPA) treatment but not in normal skin. Unlike other members of the LOX 'family' expressed in mouse skin, this TPA-induced expression of 8S-LOX is prominent only in the skin of the TPA tumor promotion-sensitive strains of mice (SENCAR, CD-1, and NMRI) but not in the promotion-resistant C57BL/6J mice. This is a very unique phenomenon among strains of mice. Constitutive upregulation of 8S-LOX was also found in early stage papillomas and the expression was gradually reduced as the tumors became malignant. Based on these observations, it has been thought that 8S-LOX is involved in TPA-induced tumor promotion as well as in tumor conversion from papillomas to carcinomas. In accordance with this hypothesis, several studies have suggested possible roles of 8S-hydroxyeicosatetraenoic acid (HETE), an AA metabolite of 8S-LOX, in mouse skin tumor development. A clastogenic activity of 8S-HETE was demonstrated in primary keratinocytes and a close correlation between the levels of etheno-DNA adducts and 8S-HETE during skin carcinogenesis was also reported. On the other hand, it has been reported that 8S-LOX protein expression is restricted to a differentiated keratinocyte compartment Moreover, reported findings on the ability of 8S-HETE to cause keratinocyte differentiation appear to be contrary to the procarcinogenic features of the 8S-LOX expression, presenting a question as to the role of 8S-LOX during mouse skin carcinogenesis. In this review, molecular and biological features of 8S-LOX as well as current views on the functional role of 8S-LOX/8S-HETE during mouse skin carcinogenesis are presented.

• Journal of Korean Neurosurgical Society
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• v.39 no.1
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• pp.26-31
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• 2006

Objective : The authors study on the clinical presentations and the surgical outcomes of the tumors in the ventricular system. Methods : 15 patients with ventricular tumor were studied. The clinical presentation, radiological findings, different surgical approaches, and outcome were analyzed. Tumors were classified into three groups based on their locations in MRI : lateral, third and fourth ventricle. Surgical methods were transcortical approach in eight patients, transcallosal approach in four, median suboccipital approach in two, and subfrontal approach in one. Gross total removal was achieved in 10 patients. Subtotal resections were performed in the rest. Glasgow outcome scale was used for evaluation of the surgical outcome. Results : Main clinical presentations were chronic headache in patients with the tumor in the lateral ventricular tumor and sudden onset of headache and consciousness change in patients with the tumor in the third and fourth ventricular tumor Development of hydrocephalus was more predominant in patients with the tumors in the third ventricle. Postoperatively, good outcome [Glasgow outcome scale IV, V] were in 73%, and better results was observed in patients with the tumors in the lateral ventricular tumor. The differences of outcome according to surgical approach were not recognized, even though it was not reliable statistically. Conclusion : In ventricular tumor, postoperative outcome is not good in patients with sudden development of headache, hydrocephalus, high grade tumor. Outcome is good in patients with the tumor in the lateral ventricle relatively. There is no difference in outcome according to the approach method to the tumors. And it is necessary to be aware of various approach methods to the tumors and anatomy surrounding the ventricle for avoidance of neurological complications.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.2
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• pp.81-93
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• 2007

Purpose: Adenoid cystic carcinoma (ACC) is a relatively rare tumor that arises in glandular tissues of the head and neck region and sometimes has a protracted clinical course with perineural invasion and delayed onset of distant lung metastasis. Treatment failure of salivary ACC is most often associated with perineural and hematogenous tumor spread. However, very little has been known about the cellular and molecular mechanisms of perineural invasion and hematogenous distant metastasis of parotid ACC. This study was designed to develop an orthotopic tumor model of parotid adenoid cystic carcinoma in athymic nude mice. Experimental Design: A melanoma cell line was injected into the parotid gland of athymic mice to determine whether such implantation was technically feasible. A parotid ACC cell line was then injected into the parotid gland or the subcutaneous tissue of athymic mice at various concentrations of tumor cells, and the mice were thereafter followed for development of tumor nodule. The tumors were examined histopathologically for perineural invasion or regional or distant lung metastasis. We used an oral squmous cell carcinoma cell line as control. Results: Implantation of tumor(melanoma) cell suspension into the parotid gland of nude mice was technically feasible and resulted in the formation of parotid tumors. A parotid ACC cell line, ACC3 showed no significantly higher tumorigenicity, but showed significantly higher lung metastatic potential in the parotid gland than in the subcutis. In contrast, mucosal squmous cell carcinoma cell line doesn’t show significantly higher lung metastatic potential in the parotid gland than in the subcutis. The ACC tumor established in the parotid gland seemed to demonstrate perineural invasion of facial nerve, needs further study. Conclusion: An orthotopic tumor model of salivary ACC in athymic nude mice was successfully developed that closely recapitulates the clinical situations of human salivary ACC. This model should facilitate the understanding of the cellular and molecular mechanisms of tumorigenisis and metastasis of salivary ACC and aid in the development of targeted molecular therapies of salivary ACC.

• Biomolecules & Therapeutics
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• v.30 no.2
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• pp.162-169
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• 2022

We utilized Fas21, a resveratrol analog, to modulate the function of hepatic stellate cells (HSCs) and liver sinusoidal endothelial cells (LSECs) during the angiogenic phase of murine liver metastasis by B16 melanoma and 51b colorectal carcinoma. Preangiogenic micrometastases were treated with Fas21 (1 mg/kg/day) or vehicle during the development of intra-angiogenic tracts. Mice treated with Fas21 showed reduced liver tumor foci in both liver metastasis models. Micrometastases were classified immunohistochemically, as well as according to their position coordinates and connection to local microvasculature. The volume of liver occupied by sinusoidal-type foci, containing infiltrating angiogenic capillaries, decreased by ~50% in Fas21-treated mice compared to vehicle-treated ones in both tumor metastasis models. The volume of portal foci, containing peripheral neoangiogenesis within a discontinuous layer of myofibroblasts, was similar in all experimental groups in both tumor metastasis models, but displayed enhanced necrotic central areas devoid of angiogenesis following Fas21 treatment. As a result, sinusoidal tumors from mice treated with Fas21 showed a 50% reduction in desmin(+)/asma(+) HSCs and CD31(+) vessel density, and a 45% reduction in intrametastatic VEGF mRNA compared with sinusoidal tumors from vehicle-treated mice. Necrotic portal metastases increased 2-4-fold in treated mice. In vitro, Fas21 reduced VEGF secretion by HSCs and 51b cells dose-dependently. Additionally, HSCs migration in response to tumor soluble factors was dose-dependently diminished by Fas21, as was LSEC migration in response to HSCs and tumor soluble factors. Resveratrol analog Fas21 inhibits the proangiogenic response of HSCs and LSECs during the development of murine liver metastasis.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.20
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• pp.8577-8579
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• 2014

Osteosarcoma is a common malignant tumor of bone, but mechanisms underlying its development are still unclear. At present, it is believed that the inhibition of normal apoptotic mechanisms is one of the reasons for the development of tumors, so specific stimulation of tumor cell apoptosis can be considered as an important therapeutic method. Livin, as a member of the newly discovered inhibitor of apoptosis proteins (IAPs) family, has specifically high expression in tumor tissues and can inhibit tumor cell apoptosis through multiple ways, which can become a new target for malignant tumor treatment (including osteosarcoma) and might of great significance in the clinical diagnosis of tumors and the screening of anti-tumor agents and carcinoma treatment.

• Korean Journal of Veterinary Research
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• v.62 no.1
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• pp.9.1-9.6
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• 2022

Canine mammary gland tumors are the most common neoplasms in intact female dogs. Approximately half of all mammary tumors are malignant, and there is a risk of metastasis, which is associated with a poor prognosis. This study was to evaluate the prognostic factors of canine mammary gland tumors and the risk factors associated with the development of malignant tumors. From 2014 to 2020, 60 dogs with mammary gland tumors that underwent surgical treatment were evaluated in this retrospective study. Tumor size, TNM stage, and histopathological results were prognostic factors for 2-year survival after surgery. Every 10 mm increase in tumor size, increased the risk of death within 2 years after surgery 1.213 times. Dogs with TNM stage IV or V had 8.667 fold risk of death within 2 years after surgery. The 2-year survival rate for dogs with benign tumors was 90.2% and for malignant tumors was 67.3%. Tumor size is the most important prognostic factor for canine mammary gland tumors. As tumor size increased by 10 mm, the risk for development of malignant tumors increased by 1.487 times. Tumors larger than 30 mm are highly likely to be malignant, and metastatic evaluation and wide resection should be considered.

• IMMUNE NETWORK
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• v.22 no.5
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• pp.38.1-38.24
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• 2022

Exosomes, which are well-known nanoscale extracellular vesicles, are multifunctional biomaterials derived from endosomes and perform various functions. The exosome is a critical material in cell-cell communication. In addition, it regulates the pathophysiological conditions of the tumor microenvironment in particular. In the tumor microenvironment, exosomes play a controversial role in supporting or killing cancer by conveying biomaterials derived from parent cells. Innate immunity is a crucial component of the host defense mechanism, as it prevents foreign substances, such as viruses and other microbes and tumorigenesis from invading the body. Early in the tumorigenesis process, the innate immunity explicitly recognizes the tumor via Ags and educates the adaptive immunity to eliminate it. Recent studies have revealed that exosomes regulate immunity in the tumor microenvironment. Tumor-derived exosomes regulate immunity against tumor progression and metastasis. Furthermore, tumor-derived exosomes regulate polarization, differentiation, proliferation, and activation of innate immune cells. Exosomes produced from innate immune cells can inhibit or support tumor progression and metastasis via immune cell activation and direct cancer inhibition. In this study, we investigated current knowledge regarding the communication between tumor-derived exosomes and innate immune cell-derived exosomes (from macrophages, dendritic cells, NK cells, and neutrophils) in the tumor microenvironment. In addition, we discussed the potential development of exosomal immunotherapy using native or engineered exosomes against cancer.