• Journal of Life Science
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• v.17 no.8 s.88
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• pp.1082-1089
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• 2007

Serological anlysis of recombinant cDNA expression libraries (SEREX) has led to identification of several categories of new antigens recognized by the immune system of cancer patients, which are referred to as the cancer immunome. We analyzed normal testis cDNA expression libraries with serumobtained from non-small lung cancer patient and isolated 40 distinct antigen designated KP-LuT-1 through KP-LuT-40. Among these antigens 20 antigens were previously identified by SEREX analysis of other tumor types, and 20 out of 40 antigens (50%) did not match entries in Cancer Immunome Database and were considered newly identified antigens. Sequencing analysis showed that the anti-gens comprised 26 functional known proteins and 14 noble/uncharacterized gene products. Of these, the hypothetical protein KP-LuT-6 was shown tissue-restricted. RT-PCR showed it to be expressed strongly only in normal testis. In addition to normal tissues-restricted expression, KP-LuT-6 mRNA was detected in lung tumor samples(3/l0), stomach tumor samples(3/l0), and breast tumor samples(l/5), whereas not detected in colon tumor samples(O/I2). These data suggest that KP-LuT-6 is a cancer/testis (CT)-like antigen as a potential target for cancer immunotherapies.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.4037-4043
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• 2012

Despite progress in elucidating mechanisms associated with colorectal cancer and improvement of treatment methods, it remains a frequent cause of death worldwide. New and more effective therapies are therefore urgently needed. Recent studies have shown that immunogenicity of whole ovarian tumor cells and subsequent T cell response were potentiated by oxidation modification with hypochlorous acid (HOCl) in vitro and ex vivo. These results prompted us to investigate the protective antitumor response with an HOCl treated CT26 colorectal cancer cell vaccine in an in vivo mouse model. Administration of HOCl modified vaccine triggered robust antitumor immunity to autologous tumor cells in mice and prolonged survival period significantly. In addition, increased necrosis and apoptosis were found in tumor tissue from the oxidation group. Interestingly, ELISPOT assays showed that specific T cell responses were not elicited in response to the immunizing cellular antigen, in contrast to raising sera antibody titer and antibody binding activity shown by ELISA assay and flow cytometry. Further evaluation of the mechanisms underlying HOCl modified vaccine mediated humoral immunity highlighted the role of antibody-dependent cell-mediated cytotoxicity. These results combined with previous studies suggest that HOCl oxidation modified whole cell vaccine has wide applicability as a cancer vaccine because it can target both T cell- and B cell-specific responses. It may thus represent a promising approach for the immunotherapy of colorectal cancer.

• Journal of Life Science
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• v.31 no.4
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• pp.400-409
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• 2021

Sanguinarine, a natural benzophenanthridine alkaloid, has been considered a potential therapeutic target for the treatment of cancer because it can induce apoptosis in human cancer cells; however, the underlying mechanisms of action still remain unclear. Tumor suppressor p53 deletion or mutation is an important reason for the resistance of colorectal cancer cells to anticancer agents. Therefore, in the present study, the role of p53 during apoptosis induced by sanguinarine was investigated in p53wild type (WT, p53+/+) and p53null (p53+/+) HCT116 colon carcinoma cells. Sanguinarine significantly caused greater reductions in cell viability in HCT116 (p53+/+) cells than in HCT116 (p53-/-) cells. Consistently, sanguinarine promoted more DNA damage and apoptosis in HCT116 (p53+/+) cells than in HCT116 (p53-/-) cells while increasing the expression of p53 and cyclin-dependent kinase inhibitor p21^WAF1/CIP1. Sanguinarine increased the activity of caspase-8 and caspase-9, which are involved in the initiation of extrinsic and intrinsic apoptosis pathways, respectively, and it activated caspase-3, a typical effect caspase, in HCT116 (p53+/+) cells. Sanguinarine also increased the generation of reactive oxygen species (ROS), and the Bax/Bcl-2 ratio, while destroying the integrity of mitochondria in HCT116 (p53+/+) cells, but not in HCT116 (p53-/-) cells. Overall, the results indicate that sanguinarine induced p53-dependent apoptosis through ROS-mediated activation of extrinsic and intrinsic apoptotic pathways in HCT116 colorectal cancer cells.

• The Korean Journal of Nuclear Medicine
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• v.37 no.6
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• pp.393-401
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• 2003

Objective: Pullulan derivatives (PD) can be used to make self-assembled hydrogel nanoparticles which are responsive to ionic strength. The aim of this study is to evaluate the potential of PD as a retaining carrier of radioisotope inside tumors. Materials and Methods: Four types of PD were evaluated which included pullulan acetate (PA), succinylated PA (SPA), PA-DTPA and SPA-DTPA conjugates. They were radiolabeled with Tc-99m. Labelling efficiencies were determined at 30 min, 1, 2, 4 and 12 hours after radiolabeling. CT-25 colon cancer cells were subcutaneously injected into Balb/c mice. After 2 weeks of subcutaneous injection, Tc-99m-labelled PD (Tc-99m-PD) were injected into the tumors. Whole body images of mice were obtained at 30 min, 1, 2, and 12 hr after intratumoral injection. All twenty mice were grouped into four groups by largest diameter; control A (largest diameter = 5 mm, n = 5), control B (largest diameter = 10 mm, n = 5), pullulan A (largest diameter = 5 mm, n = 5), pllulan B (largest diameter = 10 mm, n = 5). Dynamic images were obtained for 1 hour after intratumoral injection. Static images were obtained at 1 hr, 2 hr, 3 hr and 4 hr after intratumoral injection with Tc-99m pertechnetate and Tc-99m-PA. Target-to-background ratios and retention rates were calculated. Results: Labeling efficiencies of PA, SPA, PA-DTPA and SPA-DTPA were $94.5{\pm}5.9%,\;97.8{\pm}3.5%\;94.2{\pm}3.8%,\;and\;92.5{\pm}6.2%$, respectively (p>0.05). Percent retention rates (%RR) of PA and PA-DTPA were significantly higher than those of control, however, those of SP-DTPA and SPA became similar to control at 4 and 12 hr, respectively. %RR of pullulan A and pullulan B at 1, 4 and 8 hr is significantly higher than that of control (p < 0.05). However, %RR between pullulan A and pullulan B were similar. Conclusion: The lonic strength dependent PD-nanoparticles are retained in the tumor. No difference of %RR according to tumor size was noted. Therapeutic application of PD labelled with beta- or alpha- emitting radionuclides can be expected.

• Investigative Magnetic Resonance Imaging
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• v.10 no.2
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• pp.81-88
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• 2006

Purpose : To evaluate the MR imaging findings of bowel wall thickening in patients with minimal to moderate cirrhosis, and analyze their clinical significances comparing with laboratory findings. Materials and Methods : We assessed retrospectively the MRI findings of 123 patients with minimal to moderate cirrhosis, and compared these with the clinical laboratory findings. We evaluated the involved sites and MR image findings of thickened bowel wall, as well as the presence of collateral vessels, ascites, and splenic size. These were compared with serum albumin and bilirubin levels, and prothrombin time. Results : Gastrointestinal wall thickening was detected at 37 sites in 25 patients (20%), and more frequently detected in moderate cirrhosis (29%) than in minimal cirrhosis (17%). Jejunum and ascending colon were the most common sites of bowel wall thickening; each was involved at 22 and 9 sites, respectively. Ascending colonic wall thickening was more commonly detected in moderate cirrhosis than in minimal cirrhosis. The thickened bowel wall showed symmetric contour, high signal intensity on T2-weighted images, mixed iso- and low signal intensity on T1-weighted images, and homogeneous or target-like enhancement. Serum albumin level was significantly lower in patients with bowel wall thickening ($3.3{\pm}0.9$ g/dl vs. $3.9{\pm}0.7$ g/dl; p=0.0024). Serum bilirubin level was significantly higher in patients with bowel wall thickening ($1.7{\pm}1.0$ mg/dl vs. $1.4{\pm}1.2$ mg/dl; p=0.0160). Bowel wall thickening did not significantly correlate with the presence of collateral vessels, ascites, splenic size, and prolongation of prothrombin time. Conclusion : In minimal to moderate cirrhosis, the MR imaging evaluation of bowel wall thickening was useful for estimating the severity of cirrhosis and laboratory findings.

• Proceedings of the Korean Nutrition Society Conference
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• 1995.11b
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• pp.11-34
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• 1995

Growth hormone (GH) plays a key role in regulating postnatal growth and can stimulate growth of animals by acting directly on specific receptors on the plasma membrane of tissues or indirectly through stimulating insulin-like growth factor (IGF)-I synthesis and secretion by the liver and other tissues. IGF-I and IGF-Ⅱ are polypeptides with structural similarity with proinsulin that stimulate cell proliferation by endocrine, paracrine and autocrine mechanisms. The initial event in the metabolic action of IGFs on target cells appears to be their binding to specific receptors on the plasma membrane. Current evidence indicates that the mitogenic actions of both IGFs are mediated primarily by binding to the type I IGF receptors, and that IGF action is also mediated by interactions with IGF-binding proteins (IGFBPs). Six distinct IGFBPs have been identified that are characterized by cell-specific interaction, transcriptional and post-translational regulation by many different effectors, and the ability to either potentiate or inhibit IGF actions. Nutritional deficiencies can have their devastating consequence during growth. Although IGF-I is the major mediator of GH's action on somatic growth, nutritional status of an organism is a critical regulator of IGF-I and IGFBPs. Various nutrient deficiencies result in decreased serum IGF-I levels and altered IGFBP levels, but the blood levels of GH are generally unchanged or elevated in malnutrition. Effects of protein, energy, vitamin C and D, and zinc on serum IGF and IGFBP levels and tissue mRNA levels were reviewed in the text. Multiple factors are involved in the regulation of intestinal epithelial cell growth and differentiation. Among these factors the nutritional status of individuals is the most important. The intestinal epithelium is an important site for mitogenic action of the IGFs in vivo, with exogenous IGF-I stimulating mucosal hyperplasia. Therefore, the IGF system appears to provide and important mechanism linking nutrition and the proliferation of intestinal epithelial cells. In order to study the detailed mechanisms by which intestinal mucosa is regulated, we have utilized IEC-6 cells, an intestinal epithelial cell line and Caco-2 cells, a human colon adenocarcinoma cell line. Like intestinal crypt cells analyzed in vivo or freshly isolated intestinal epithelial cells, IEC-6 cells and Caco-2 cells possess abundant quatities of both type Ⅰ and type Ⅱ IGF receptors. Exogenous IGFs stimulate, whereas addition of IGFBP-2 inhibits IEC-6 cell proliferation. To investigate whether endogenously secreted IGFBP-2 inhibit proliferation, IEC-6 cells were transfected with a full-length rat IGFBP-2 cDNA anti-sense expression construct. IEC-6 cells transfected with anti-sense IGFBP-2 protein in medium. These cells grew at a rate faster than the control cells indicating that endogenous IGFBP-2 inhibits proliferation of IEC-6 cells, probably by sequestering IGFs. IEC-6 cells express many characteristics of enterocyte, but do not undergo differentiation. On the other hand, Caco-2 cells undergo a spontaneous enterocyte differentiation. On the other hand, Caco-2 cells undergo a spontaneous enterocyte differentiation after reaching confluency. We have demonstrated that Caco-2 cells produce IGF-Ⅱ, IGFBP-2, IGFBP-3, and an as yet unidentified 31,000 Mr IGFBP, and that both mRNA and peptide secretion of IGFBP-2 and IGFBP-3 increased, but IGFBP-4 mRNA and protein secretion decreased after the cells reached confluency. These changes occurred in parallel to and were coincident with differentiation of the cells, as measured by expression of sucrase-isomaltase. In addition, Caco-2 cell clones forced to overexpress IGFBP-4 by transfection with a rat IGFBP-4 cDNA construct exhibited a significantly slower growth rate under serum-free conditions and had increased expression of sucrase-isomaltase compared with vector control cells. These results indicate that IGFBP-4 inhibits proliferation and stimulates differentiation of Caco-2 cells, probably by inhibiting the mitogenic actions of IGFs.

• Journal of the Korean Magnetics Society
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• v.26 no.5
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• pp.173-178
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• 2016

This study is to evaluate the effect of a Contrast Media (CM) on dose calculations and clinical significance in Radiation (Electromagnetic wave) Therapy (RT) plans for head & neck (H&N) and prostate cancer. Pinnacle 8.0 system was used to measure the change of Electron Density (ED) of the tissue for CM. To determine the effect of dose calculation due to CM, we did the RT planning for 30 patients. To compare the ED and dose calculations of RT plans, 3D CRT and IMRT plans were do with pinnacle and Tomotherapy planning system. Mean difference of ED between enhanced and unenhanced CT was less than 4%: H&N Target Volume (TV) 2.1%, parotid 1.9%, SMG 3.6%, tongue 0.9%, spinal cord 0.3%, esophagus 2.6%, mandible 0.1% and prostate TV 0.7%, lymph node 1.1%, bladder 1.2%, rectum 1.5%, small bowel 1.2%, colon 0.6%, penile bulb 0.8%, femoral head -0.2%. The dose difference between RT plan using CM and without CM showed an increase of dose in TV. The rate of increase was less than 2.5% (3D CRT: H&N 0.69~2.51%, prostate 0.04~1.14%, IMRT: H&N 0.58~1.31%, prostate 0.36~1.04%). RT plans using a CM has the insignificant effect on the organs and TV, so this error is allowable clinically. However, the much more accurate plan is possible as to image fusion (CM and without CM images) to ROI contour and when dose calculation, use the without CM image. Using the fusion of 'ROI import' perform calculations on without CM, it will be able to reduce the error (1~3%) caused by the CM.

• Journal of Gastric Cancer
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• v.4 no.4
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• pp.207-212
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• 2004

Purpose: Invasion and metastasis in solid tumors require the action of tumor-associated proteases. The serine protease urokinase-type plasminogen (uPA) and receptor (uPAR) appear to have a major function in these processes. Expression of the uPAR is elevated in breast and colon carcinomas, and this is often associated with invasiveness and poor prognosis. The purpose of this study was to determine whether the expression of the uPAR gene correlates with clinico-pathological parameters in human gastric carcinomas. Materials and Methods: We examined the expression of uPAR mRNA by using northern blot analysis and RT-PCR in 35 gastric carcinomas and the surrounding normal mucosa. Macroscopic and histopathological tumor findings and survival rates were obtained from the patient records and from endoscopic, surgical, and pathological reports. Results: The expression of uPAR and was higher in most neoplasms than in the corresponding normal mucosal tissue. uPAR mRNA expression in tumors correlated well with lymph-node metastasis (P<0.02) and tumor stage (P<0.01). The survival rate of patients with tumors displaying high uPAR expression levels was significantly lower (P<0.04) than that of patients without uPAR expression, but IL-8 showed only the tendency of survival difference. Conclusion: These results suggest that uPAR may be an important prognostic factor in human gastric carcinomas.

• Journal of Life Science
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• v.27 no.11
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• pp.1245-1255
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• 2017

Most cancer cells produce ATP predominantly through glycolysis instead of through mitochondrial oxidative phosphorylation, even in the presence of oxygen. The phenomenon is termed the Warburg effect, or the glycolytic switch, and it is thought to increase the availability of biosynthetic precursors for cell proliferation. EMTs have critical roles in the initiation of the invasion and metastasis of cancer cells. The glycolytic switch and EMT are important for tumor development and progression; however, their correlation with tumor progression is largely unknown. The Snail transcription factor is a major factor involved in EMT. The Snail expression is regulated by distal-less homeobox 2 (Dlx-2), a homeodomain transcription factor that is involved in embryonic and tumor development. The Dlx-2/Snail cascade is involved in Wnt-induced EMTs and the glycolytic switch. This study showed that in response to Wnt signaling, the Dlx-2/Snail cascade induces the expression of PFKFB2, which is a glycolytic enzyme that synthesizes and degrades fructose 2, 6-bisphosphate (F2,6BP). It also showed that PFKFB2 shRNA prevents Wnt-induced EMTs in the breast-tumor cell line MCF-7. The prevention indicated that glycolysis is linked to Wnt-induced EMT. Additionally, this study showed PFKFB2 shRNA suppresses in vivo tumor metastasis and growth. Finally, it showed the PFKFB2 expression is higher in breast, colon and ovarian cancer tissues than in matched normal tissues regardless of the cancers' stages. The results demonstrated that PFKFB2 is an important regulator of EMTs and metastases induced by the Wnt, Dlx-2 and Snail factors.