• IMMUNE NETWORK
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• v.12 no.4
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• pp.155-164
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• 2012

It is well established that blocking the interaction of EGFR with growth factors leads to the arrest of tumor growth, resulting in tumor cell death. ER414 is a human monoclonal antibody (mAb) derived by guided selection of the mouse mAb A13. The ER414 exhibited a ~17-fold lower affinity and, as a result, lower efficacy of inhibition of the EGF-mediated tyrosine phosphorylation of EGFR when compared with mAb A13 and cetuximab. We performed a stepwise in vitro affinity maturation to improve the affinity of ER414. We obtained a 3D model of ER414 to identify the amino acids in the CDRs that needed to be mutated. Clones were selected from the phage library with randomized amino acids in the CDRs and substitution of amino acids in the HCDR3 and LCDR1 of ER414 led to improved affinity. A clone, H3-14, with a ~20-fold increased affinity, was selected from the HCDR3 randomized library. Then three clones, ER2, ER78 and ER79, were selected from the LCDR1 randomized library based on the H3-14 but did not show further increased affinities compared to that of H3-14. Of the three, ER2 was chosen for further characterization due to its better expression than others. We successfully performed affinity maturation of ER414 and obtained antibodies with a similar affinity as cetuximab. And antibody from an affinity maturation inhibits the EGF-mediated tyrosine phosphorylation of EGFR in a manner similar to cetuximab.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.37 no.2
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• pp.97-108
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• 2011

Cancer stem cells have stem cell-like features, such as the ability for self-renewal and differentiation but show unlimited growth because they have the lost normal regulation of cell growth. Cancer stem cells and normal stem cells have similar features. They show high motility, diversity of progeny, robust proliferative potential, association with blood vessels, immature expression profiles, nestin expression, epidermal growth factor (EGF)-receptor expression, phosphatase and tensin homolog (PTEN) expression, hedgehog pathway activity, telomerase activity, and Wnt pathway activity. On the other hand, with cancer cells, some of these signaling pathways are abnormally modified. In 1875, Cohnheim suggested the concept of cancer stem cells. Recently, evidence for the existence of cancer stem cells was identified. In 1994, the cancer stem cells' specific cell surface marker for leukemia was identified. Since then, other specific cell surface markers for cancer stem cells in solid tumors (e.g. breast and colon cancer) have been identified. In oral cancer, studies on cancer stem cells have been performed mainly with squamous cell carcinomas. Oral cancer specific cell surface markers, which are genes strongly expressed in oral cancer and cancer stem cell specific side populations, have been identified. Cancer stem cells are resistant to radiotherapy and chemotherapy. Therefore, to eliminate malignant tumors efficiently and reduce the recurrence rate, therapy targeting cancer stem cells needs to be performed. Currently, studies targeting the cancer stem cells' specific signaling pathways, telomerase and tumor vasculatures are being done.

• Radiation Oncology Journal
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• v.28 no.2
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• pp.57-63
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• 2010

Purpose: We performed an immunohistochemical study with pre-treatment biopsy specimens to evaluate the prognostic significance of four biomolecular markers which can be used as a predictive assay for radiotherapy (RT) treatment of nasopharyngeal carcinoma (NPC). Materials and Methods: From January 1998 through December 2006, 68 patients were histologically diagnosed as non-metastatic NPC and treated by RT. Only 38 patients had the paraffin block for the immunohistochemical study. Thirty-one patients had undifferentiated carcinoma and 7 patients had squamous cell carcinoma. Thirtytwo patients (84%) had advanced stage NPC (2002 AJCC Stage III~IV). Immunohistochemical staining was performed for Met, COX-2, nm23-H1, and epidermal growth factor receptor (EGFR) expression using routine methods. Results: The median follow-up time was 30 months (range, 11 to 83 months) for all patients, and 39 months (range, 19 to 83 months) for surviving patients. The 5-year overall survival (OS) rate of the patients with high Met extent (${\geq}50%$) was significantly lower than that of the patients with low Met extent (48% vs. 84%, p=0.02). In addition, Met extent was also a significant prognostic factor in multivariate analysis (p=0.01). No correlation was observed between Met extent and T stage, N stage, stage group, gender, age, and the response to chemotherapy or RT. Met extent showed moderate correlation with COX-2 expression (Pearson coefficient 0.496, p<0.01), but COX-2 expression did not affect OS. Neither nm23-H1 or EGFR expression was a prognostic factor for OS in this study. Conclusion: High Met extent (${\geq}50%$) might be an independent prognostic factor that predicts poor OS in NPC treated with RT.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.12
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• pp.4959-4964
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• 2015

Background: To assess the immunohistochemical expression of estrogen receptor (ER), progesterone receptor (PgR) and human epidermal growth factor receptor-2 (HER2) neu receptor in breast cancer and their associations with various clinicopathological characteristics. Materials and Methods: This is a retrospective analysis of women who presented with primary, unilateral breast cancer in the Department of Medical Oncology at Rajiv Gandhi Cancer Institute and Research Centre, Delhi, India during the period from January 2008 to December 2011. Data were retrieved from the medical records of the hospital including both early and locally advanced cancer cases. ER, PgR and HER2neu expression in these patients was assessed and triple negative patients were identified. Associations of triple negative and non-triple negative groups with clinicopathological characteristics were also evaluated. Results: A total of 1,284 women (mean age 52.1 years, 41.9% premenopausal) were included in the analysis. Hormone receptor positivity (ER and/or PgR) was seen in 63.4% patients, while 23.8% of tumors were triple negative. Only 23.0% were HER2 positive. Around 10.0% of tumors were both ER and HER2 positive. ER and PgR positivity was significantly associated with negative HER2 status (p-value <0.0001). Younger age, premenopausal status, higher tumor grade, lymph node negativity, advanced cancer stage, and type of tumor were strongly associated with triple negativity. Significantly, a smaller proportion of women had ductal carcinoma in situ in the triple negative group compared with the non-triple negative group (35.6% versus 60.8%, p-value<0.01). Conclusions: The present analysis is one of the largest studies from India. The majority of the Indian breast cancer patients seen in our hospital present with ER and PgR positive tumors. The triple negative patients tended to be younger, premenopausal, and were associated with higher tumor grades, negative lymph nodes status and lower frequency of ductal carcinoma in situ.

• Journal of Chest Surgery
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• v.31 no.4
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• pp.362-368
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• 1998

The aim of this study was to evaluate a usefulness of serum SCC antigen in diagnosis or evaluation of therapeutic effect of lung cancer by investigation of the differences of SCC antigen concentration in lung mass according to TNM staging, and mass size of lung cancer. And the other aim was to know whether SCC antigen plays a role in infiltrative growth of lung cancer or not, comparing with concentration of epidermal growth factor receptor(EGFr) in tissue which is related with growth and differentiation of tumor cell. The results of this study were as follows. The concentration of SCC antigen in squamous cell carcinoma of lung(69${\pm}$25ng/ml) was higher than in unaffected lung tissue(34${\pm}$7ng /ml).(p＜0.05). The concentration of SCC antigen was higher in squamous cell carcinoma (69${\pm}$25ng/ml) than in adenocarcinoma (35${\pm}$25ng/ml) (p＜0.05), but the concentration of EGFr showed no any significant difference in both histological types. In small sized mass(＜3cm in diameter) the concentration of SCC antigen in central portion of tumor was higher than that of peripheral portion, whereas in large sized mass($\geq$5cm in diameter), the concentration of SCC antigen in peripheral portion of tumor was higher than that of central portion.(p＜0.05). The concentration of EGFr according to tumor size was not significantly different in central and peripheral portion of tumor. The concentration of SCC antigen according to TNM staging of lung cancer was that from central portion was higher in stage I, II, but that from peripheral portion was higher in stage III, IV (p＜0.05). The concentration of EGFr from central portion was higher in higher TNM stage(not significant) but that from peripheral portion shows no significant changes. In conclusion, the concentration of SCC antigen in tissue was higher in squamous cell carcinoma than in unaffected lung tissue or adenocarcinoma, and the concentration of SCC antigen increased according to tumor size or TNM staging like in serum level. so, serum SCC antigen is a useful tumor marker to diagnose or evaluate therapeutic effect of squamous cell carcinoma of lung. But further studies are necessary to confirm the relation of infiltrative growth in lung cancer and concentration of SCC antigen because there was a different pattern of regional tissue concentration of SCC antigen and EGFr

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10577-10583
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• 2015

Background: Triple-negative breast cancer (TNBC), characterized by the lack of expression of estrogen receptor, progesterone receptor and human epidermal growth factor receptor-2, is typically associated with a poor prognosis. The majority of TNBCs show the expression of basal markers on gene expression profiling and most authors accept TNBC as basal-like (BL) breast cancer. However, a smaller fraction lacks a BL phenotype despite being TNBC. The literature is silent on non-basal-like (NBL) type of TNBC. The present study was aimed at defining behavioral differences between BL and NBL phenotypes. Objectives: i) Identify the TNBCs and categorize them into BL and NBL breast cancer. ii) Examine the behavioral differences between two subtypes. iii) Observe the pattern of treatment failure among TNBCs. Materials and Methods: All TNBC cases during January 2009-December 2010 were retrieved. The subjects fitting the inclusion criteria of study were differentiated into BL and NBL phenotypes using surrogate immunohistochemistry with three basal markers $34{\beta}E12$, c-Kit and EGFR as per the algorithm defined by Nielsen et al. The detailed data of subjects were collated from clinical records. The comparison of clinicopathological features between two subgroups was done using statistical analyses. The pattern of treatment failure along with its association with prognostic factors was assessed. Results: TNBC constituted 18% of breast cancer cases considered in the study. The BL and NBL subtypes accounted for 81% and 19% respectively of the TNBC group. No statistically significant association was seen between prognostic parameters and two phenotypes. Among patients with treatment failure, 19% were with BL and 15% were with NBL phenotype. The mean disease free survival (DFS) in groups BL and NBL was 30.0 and 37.9 months respectively, while mean overall survival (OS) was 31.93 and 38.5 months respectively. Treatment failure was significantly associated with stage (p=.023) among prognostic factors. Conclusions: Disease stage at presentation is an important prognostic factor influencing the treatment failure and survival among TNBCs. Increasing tumor size is related to lymph node positivity. BL tumors have a more aggressive clinical course than that of NBL as shown by shorter DFS and OS, despite having no statistically significant difference between prognostic parameters. New therapeutic alternatives should be explored for patients with this subtype of breast cancer.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.2
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• pp.236-245
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• 2017

Objective: The study was to investigate the effects of alanyl-glutamine (Ala-Gln) and glutamine (Gln) supplementation on the intestinal mucosa barrier in piglets. Methods: A total of 180 barrows with initial weight $10.01{\pm}0.03kg$ were randomly allocated to three treatments, and each treatment consisted of three pens and twenty pigs per pen. The piglets of three groups were fed with control diet [0.62% alanine (Ala)], Ala-Gln diet (0.5% Ala-Gln), Gln diet (0.34% Gln and 0.21% Ala), respectively. Results: The results showed that in comparison with control diet, dietary Ala-Gln supplementation increased the height of villi in duodenum and jejunum (p<0.05), Gln supplementation increased the villi height of jejunum (p<0.05), Ala-Gln supplementation up-regulated the mRNA expressions of epidermal growth factor receptor and insulin-like growth factor 1 receptor in jejunal mucosa (p<0.05), raised the mRNA expressions of Claudin-1, Occludin, zonula occludens protein-1 (ZO-1) and the protein levels of Occludin, ZO-1 in jejunal mucosa (p<0.05), Ala-Gln supplementation enlarged the number of goblet cells in duodenal and ileal epithelium (p<0.05), Gln increased the number of goblet cells in duodenal epithelium (p<0.05) and Ala-Gln supplementation improved the concentrations of secretory immunoglobulin A and immunoglobulin G in the jejunal mucosa (p<0.05). Conclusion: These results demonstrated that dietary Ala-Gln supplementation could maintain the integrity of small intestine and promote the functions of intestinal mucosa barriers in piglets.

• BMB Reports
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• v.34 no.3
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• pp.189-193
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• 2001

Curcumin a yellow pigment from Curcuma Tonga, has been known to possess antioxidative and anticarcinogenic properties, as well as to induce apoptosis in some cancer cells. There have been, however, several contradictory reports that hypothesized curcumin (a hydrophobic molecule) can bind a membrane Gpid bilayer and induce nonspecific cytotoxicity in some cell lines. Why curcumin shows these contradictory effects is unknown. In A-431 cells, growth inhibition by curcumin is due mostly to the specific inhibition of the intrinsic tyrosine kinase activity of the epidermal growth factor receptor, as reported earlier by Korutla et al. Thus, we assumed that the cell death of A-431 by curcumin might be due to the specific induction of apoptosis. In this paper we clearly show that curcumin induces apoptosis in A-431 cells. The cureumin-induced cell death of A-431 exhibited various apoptotic features, including DNA fragmentation and nuclear condensation. Furthermore, the curcumin-induced apoptosis of A-431 cells involved activation of caspase-3-like cysteine protease. Involvement of caspase-3 was further confirmed by using a caspase-3 specific inhibitor, DEVD-CHO. In another study, decreased nitric oxide (NO) production was also shown in A-431 cells treated with curcumin, which seems to be the result of the inhibition of the iNOS expression by curcumin, as in other cell lines. However, 24 h after treatment of curcumin there was increased NO production in A-431 cells. This observation has not yet been clearly explained. We assumed that the increased NO production may be related to denitrosylation of the enzyme catalytic site in caspase-3 when activated. Taken together, this study shows that the cell death of A-431 by curcumin is due to the induction of apoptosis, which involves caspase-3 activation.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.15
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• pp.6445-6449
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• 2015

Background: NSCLC is a disease involving uncontrolled cell growth, which could result in metastases into nearby tissues beyond the lungs. Materials and Methods: The aim of the present study was to analyze the influence of epidermal growth factor receptor (EGFR) gene expression on metastasis and survival in NSCLC patients. The present case-control study included 100 cases of NSCLC patients and 100 age and sex matched controls. EGFR gene expression was analyzed by quantitative real time PCR using serum RNA. Association with NSCLC patient survival was analyzed by the Kaplan-Meier method. Results: We analyzed EGFR gene expression and observed mean increased gene expression of 13.5 fold in NSCLC patients. Values reflected overall survival of patients with a median of 15.8 months in the cases of <13 fold increased gene expression vs 6.7 months with >13 fold increased EGFR gene expression (p=0.005). Distant metastatic patients with <13 fold increased EGFR gene expression had 7.9 months of median survival time while>13 fold increased EGFR gene expression had only 5 months of median survival time (p=0.03). Non metastatic patients with <13 fold increased EGFR gene expression had 18 months of median survival time as compared to only 7.1 months with >13 fold increased expression. Conclusions: Higher cell free EGFR mRNA expression may play an important role in causing distant metastases and reducing overall survival of NSCLC patients in the Indian population.

• Biomedical Science Letters
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• v.20 no.2
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• pp.85-95
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• 2014

Activation of the epidermal growth factor receptor (EGFR) and downstream signaling pathways have been implicated in causing resistance to EGFR-targeted therapy in solid tumors, including the head and neck tumors. To investigate the mechanism of antiproliferation to EGFR inhibition in oral cancer, we compared EGFR tyrosine kinase inhibitor (Gefitinib, Iressa, ZD1839) with respect to its inhibitory effects on three kinases situated downstream of EGFR: MAPK, Akt, and glycogen synthase kinase-$3{\beta}$ (GSK-$3{\beta}$). We have demonstrated that ZD1839 induces growth arrest and apotosis in oral cancer cell lines by independent of EGFR-mediated signaling. An exposure of oral cancer cells to ZD1839 resulted in a dose dependent up-regulation of the cyclin-dependent kinase inhibitor p21 and p27, down regulation of cyclin D1, inactivation of GSK-$3{\beta}$ and of active MAPK. In resistant cells, GSK-$3{\beta}$ is constitutively active and its activity is negatively regulated primarily through Ser 9 phosphorylation and further enhanced by Tyr216 phosphorylation. These results showed that the resistance to the antiproliferative effects of ZD1839, in vitro was associated with uncoupling between EGFR and MAPK inhibition, and that GSK-$3{\beta}$ activation and degradation of its target cyclin D1 were indicators of high cell sensitivity to ZD1839. In conclusion, our data show that the uncoupling of EGFR with mitogenic pathways can cause resistance to EGFR inhibition in oral cancer.