• Biomedical Science Letters
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• v.8 no.3
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• pp.137-142
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• 2002

The expression of CD44v is known as a marker of cancer progression and its metastasis in colorectal cancer. It has been known that CD44 variant containing sequences encoded by exon 11 (v6) confer metastatic potential to human colorectal cancer cells. The role of CD44 standard (CD44s) and CD44v6 in colorectal cancer was investigated in this study by immunohistochemical staining of the primary tumors obtained from the colorectal cancer patients. Immunohistochemical staining was performed in 40 patients with colorectal cancer who underwent curative surgery at Keimyung University hospital. The expression CD44s and CD44v6 was observed in 24/40 (60%) and 13/40 (32.5%) respectively. The expression of CD44v6 had correlation with TNM stage (P＜0.05), however CD44s had not any correlation with clinicopathological parameters. These results suggest that CD44v6 expression may give an information for tumor progression than decreased expression of CD44s in colorectal cancer cells.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.8
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• pp.3791-3794
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• 2012

CD44v, especially splice variants containing exon v6, has been shown to be related closely to development of different tumors. High levels of CD44v6/v7 have been reported to be associated with invasiveness and metastasis of many malignancies. The objective of this study was to detect expression of CD44v6-containing variants in patients with acute promyelocytic leukemia (APL) and evaluate the potential of CD44v6/v7 for risk stratification. Reverse transcription polymerase chain reaction (RT-PCR) followed by PCR product purification, ligation into T vectors and positive clone sequencing were used to detect CD44 v6-containing variant isoforms in 23 APL patients. Real-time quantitative PCR of the CD44v6/v7 gene was performed in patients with APL and in NB4 cells that were treated with all-trans retinoic acid (ATRA) or arsenic trioxide ($As_2O_3$). Sequencing results identified four isoforms (CD44v6/v7, CD44v6/v8/v10, CD44v6/v8/v9/v10, and CD44v6/v7/v8/v9/v10) in bone marrow mononuclear cells of 23 patients with APL. The level of CD44v6/v7 in high-risk cases was significantly higher than those with low-risk. Higher levels of CD44v6/v7 were found in three patients with central nervous system relapse than in other patients inthe same risk group. Furthermore, in contrast to ATRA, only $As_2O_3$ could significantly down-regulate CD44v6/v7 expression in NB4 cells. Our data suggest that CD44v6/v7 expression may be a prognostic indicator for APL.

• Journal of Gastric Cancer
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• v.1 no.1
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• pp.10-16
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• 2001

Purpose: The p53 protein is a tumor supressor gene, and its mutation is associated with biologic aggressiveness. CD44v6, one of the CD44 family, is a cell surface glycoprotein that plays a role in cancer invasion and metastasis. Vascular endothelial growth factor (VEGF) is another recently identified growth factor with significant angiogenic properties. The purpose of this study was to investigate p53, CD44v6, and VEGF expressions to determine whether degree of expression was related to pathological parameters such as Lauren's classification, depth of invasion, and lymph node metastasis. Materials and Methods: Immunohistochemical stains of p53, CD44v6, and VEGF in formalin-fixed paraffin-embedded tissue sections of 125 gastric adenocarcinomas were done. Results: The overall expression rates of p53, CD44v6, and VEGF were $54.4\%$ (68/125), $36.8\%$ (46/125), and $48.0\%$ (60/125), respectively. The p53, not CD44v6 and VEGF was higher in intestinal-type gastric carcinomas by Lauren's classification. The expressions of p53, CD44v6, and VEGF were statistically correlated with depth of tumor invasion. The expression of CD44v6 was higher in the lymph node metastatic group than in the negative group. The p53 expression was significantly associated with VEGF expression. Conclusions: These data suggest that the expressions of p53, CD44v6, and VEGF are biologically related to malignancy. The p53 and CD44v6 expressions are independent; however, p53 gene mutation is one of the contributing factors to VEGF expression in gastric adenocarcinoma.

• Journal of Chest Surgery
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• v.39 no.1 s.258
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• pp.1-11
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• 2006

Background: CD44 is a glycoprotein on the cell surface which is involved in the cell-to-cell and cell-to-matrix interaction. The standard form, CD44s and multiple isoforms are determined by alternative splicing of 10 exons. Recent studies have suggested that CD44 may help invasion and metastasis of various epithelial tumors as well as activation of Iymphocytes and monocytes. The expression pattern of CD44 can be different according to tumor types. The author studied the expression pattern of CD44s and one of its variants, CD44v6 in non-small cell lung carcinomas (NSCLC) to find their implications on clinicopathologic aspects, including the survival of the patients. Material and Method: A total of 89 primary NSCLSs (48 squamous cell carcinomas, 33 adenocarcinomas, and 8 undifferentiated large cell carcinomas) were retrieved during the years between 1985 to 1994. The immunohisto chemistry was done by using monoclonal antibodies and the CD44 expression for angiogenesis was evaluated by counting the number of tumor microvessels. Result: Seventy-one (79.8$\%$) and 64 (71 .9$\%$) among 89 NSCLSs revealed the expression of CD44s and CD44v6, respectively. The expression of CD44s was well correlated with that of CD44v6 (r=0.710, p < 0.0001). The expression of CD44s and CD44v6 was associated with the histopathologic type of the NSCLCs, and squamous cell carcinoma was the type that showed the highest expression of CD44s and CD44v6 (p < 0.0001). Microvessel count was the highest in adenocarcinomas (113.6$\pm$69.7 on 200-fold magnification and 54.8$\pm$41.1 on 400-fold magnification) and correlated with the tumor size of TNM system (r=0.217, p=0.043) and CD44s expression (r=0.218, p=0.040). In adenocarcinoma, the patients with higher CD44s expression survived shorter than those with lower CD44s expression (p=0.0194) but there was no statistical significance on multivariate analysis(p=0.3298). Conclusion: The expression of both CD44s and CD44v6 may be associated with the squamous differentiation in non-small cell lung carcinomas. The relationship of CD44s expression with micro-vessel density of the tumor suggests an involvement of CD44s in tumor angiogenesis, which in turn would help tumor growth.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.16
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• pp.6761-6766
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• 2014

Background: CD44v6 (CD44 variant exon 6) is the chief CD44 variant isoform regulating tumor invasion, progression, and metastasis. The prognostic value of CD44v6 expression in non small cell lung cancer (NSCLC) has been evaluated in many studies, but the results have remained controversial. Thus, we performed a meta-analysis of currently available studies to investigate the prognostic value of CD44v6 expression in NSCLC patients and the relationship between the expression of CD44v6 and clinicopathological features. Materials and Methods: Two independent reviewers searched the relevant literature in Pubmed, Medline and Embase from 1946 to January 2014. Overall survival (OS) and various clinicopathological features were collected from included studies. This meta-analysis was accomplished using STATA 12.0 and Revman 5.2 software. Pooled hazard ratios (HRs) with 95% confidence intervals (95%CIs) were calculated to estimate the effects. Results: A total of 921 NSCLC patients from ten studies met the inclusion criteria. The results showed that CD44v6 high expression was a prognostic factor for poor survival (HR=1.91, 95%CI=1.12-3.26, p<0.05). With respect to clinicopathological features, CD44v6 high expression was related to histopathologic type (squamous cell carcinoma versus adenocarcinoma: OR=2.72, 95%CI=1.38-5.38, p=0.004), and lymph node metastasis (OR=3.02, 95%CI=1.93-4.72, p<0.00001). Conclusions: Our results suggested CD44v6 high expression as a poor prognostic factor for NSCLC, and CD44v6 expression is associated with lymph node metastasis and histopathologic type. Therefore, CD44v6 expression can be used as a novel prognostic marker in NSCLC cases.

• BMB Reports
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• v.49 no.11
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• pp.612-616
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• 2016

CD44 pre-mRNA includes 20 exons, of which exons 1-5 ($C_1-C_5$) and exons 16-20 ($C_6-C_{10}$) are constant exons, whereas exons 6-15 ($V_1-V_{10}$) are variant exons. $V_6$-exon-containing isoforms have been known to be implicated in tumor cell invasion and metastasis. In the present study, we performed a SR protein screen for CD44 $V_6$ splicing using overexpression and lentivirus-mediated shRNA treatment. Using a CD44 $V_6$ minigene, we demonstrate that increased SRSF3 and SRSF4 expression do not affect $V_6$ splicing, but increased expression of SRSF1, SRSF6 and SRSF9 significantly inhibit $V_6$ splicing. In addition, using a constitutive exon-specific primer set, we could not detect alterations of CD44 splicing after SR protein-targeting shRNA treatment. However, using a $V_6$ specific primer, we identified that reduced SRSF2 expression significantly reduced the $V_6$ isoform, but increased $V_{6-10}$ and $V_{6,8-10}$ isoforms. Our results indicate that SR proteins are important regulatory proteins for CD44 $V_6$ splicing.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.5
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• pp.2221-2224
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• 2014

Objective: To explore the relationship between expressions of cell adhesion molecules CD44 v6 and E-cadherin (E-cad) and lymphatic metastasis in non-small cell lung cancer (NSCLC). Materials and Methods: Eightyseven tissue samples obtained from patients with primary NSCLC were collected in our hospital from Dec., 2007 to Dec., 2012, and the expressions of CD44 v6 and E-cad gene proteins in these samples were detected by immunohistochemical method. Results: In the tissue without lymphatic metastasis, the positive expression rate of CD44 v6 was significantly lower, whereas the normal expression rate of E-cad was notably higher than that with lymphatic metastasis (55.6% vs. 78.4%, 47.2% vs. 21.6%), and both differences had statistical significance (P<0.05). Besides, CD44 v6 and E-cad expressions had a significant correlation in the NSCLC tissue with lymphatic metastasis (P<0.05). Conclusions: The positive expression of CD44 v6 and abnormal expression of E-cad may play a very important role in promoting lymphatic metastasis of NSCLC, with synergistic effect. Hence, detection of CD44 v6 and E-cad expressions is conductive to judging the lymphatic metastasis in NSCLC.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.12
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• pp.5049-5053
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• 2014

Background: To investigate the expression of CD44v3 and vascular endothelial growth factor-C (VEGF-C) and their relationship with lymph node metastasis in squamous cell carcinomas (SCC) of the uterine cervix. Materials and Methods: Expression of CD44v3 and VEGF-C was analyzed in 109 cases of cervical SCC by immunohistochemistry (IHC). The relationship was analyzed between expression and the patient age, histological differentiation, formation of tumor emboli in lymphoid vessels, lymph node metastasis, FIGO staging, and TNM classification. Results: Expression rates for both CD44v3 and VEGF-C were 43.1% in cervical SCC. The cells with positive immunohistochemical staining of CD44v3 were distributed mainly around the keratin pearls in well differentiated carcinomas, but distributed diffusely in the moderately and poorly differentiated lesions. VEGF-C was found stained positively in most of the tumor cells. There were differences in expression between normal epithelium and atypical hyperplasia as well as carcinoma. Both CD44v3 and VEGF-C were found to be associated positively with lymph node metastasis and TNM classification (both p=0.000). Neither CD44v3 nor VEGF-C was found to be associated with patient age, histological differentiation, formation of tumor emboli in lymphoid vessels and FIGO staging. CD44v3 was found to be associated with VEGF-C positively (p=0.000). Conclusions: Abnormal expression of CD44v3 and VEGF-C is associated closely with the lymph node metastasis in cervical SCC, and these agents may cooperate in carcinogenesis and development of metastatic lesions.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.5 no.1
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• pp.78-86
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• 1995

Abstract We have investigated the structure and the conductivity of the CdTe films evaporated on the glass substrates by Electron Beam Evaporator (EBE) technique. The structure is observed to be polycrystalline whose phase is mainly hexagonal phase with some cubic phase. Dark electric conductivity is of the order of $1-^{-8} {\Omega}^{-1} cm^{-1}$ and slightly increased by annealing for an hour at $300^{\circ}C$. Activation energy calculated from the electrical conductivity which varies with increasing temperature is 1.446 eV in the case of room temperature substrates. The values of optical band gap are 1.52 eV in direct transition whereas 1.44 eV in indirect. The photoconductivity of the films is of the order of $1-^{-8} {\Omega}^{-1} cm^{-1}$ and the peak energy is about 600 nm in the room temperature. The photoconductivity starts to increase at 850 nm, which is close to 1.446 eV, the activation energy of CdTe polycrystal films.

• Biomedical Science Letters
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• v.18 no.3
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• pp.210-217
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• 2012

Oncolytic viral vectors have shown good candidates for cancer treatment but have many limitations. To improve the therapeutic potential of oncolytic vaccinia virus, we developed a recombinant vaccinia virus expressing the 4-1BBL co-stimulatory molecule or CCL21. 4-1BBL and CCL21 expression was identified by FACS analysis and immunoblotting. rV-4-1BBL vaccination shows significant tumor regression compared to rV-LacZ, but rV-CCL21 shows rapid tumor growth compared to rV-LacZ in the poorly immunogenic B16 murine melanoma model. 4-1BBL expression resulted in the increase of the number of CD8+ T cells and especially the increase of effector (CD62L-CD44+) CD8+ T cells. These data suggest 4-1BBL may be the potential target for enhancement of tumor immunotherapy.