Earticle

Receptor tyrosine kinase c-Kit, a marker found on interstitial cells of Cajal (ICCs), is expressed in Leydig cells, which are testicular interstitial cells. The expression of other ICC markers has not yet been reported. In this study, we investigated the expression of c-Kit and anoctamin 1 (ANO1), another ICC marker, in mouse testes. In addition, the relationship between c-Kit and ANO1 expression and Leydig cell function was investigated. We observed that c-Kit and ANO1 were predominantly expressed in mouse Leydig cells. The mRNA and protein of c-Kit and ANO1 were expressed in TM3, a mouse Leydig cell line. LH induced an increase in intracellular Ca2+ concentration, membrane depolarization, and testosterone secretion, whereas these signals were inhibited in the presence of c-Kit and ANO1 inhibitors. These results show that c-Kit and ANO1 are expressed in Leydig cells and are involved in testosterone secretion. Our findings suggest that Leydig cells may act as ICCs in testosterone secretion.

소의 흰 반점 관련 후보유전자로 c-KIT receptor 유전자를 선정하여, c-KIT receptor 유전자내의 변이를 탐색하고 변이가 흰반점 표현형과 연관성이 있는지를 분석하였다. 한우, Angus, Brown Swiss, Charolais, Hereford, Hols- tein, Limousin 및 Simmental 등 8개 품종의 DNA 시료를 사용하여 c-KIT receptor 유전자의 intron 6번 영역에서 다형성을 조사하고 분석하였다. c-KIT receptor 유전자의 intron 6번 영역에서는 4개의 염기치환이 발견되어, MspⅠ, BsrBⅠ 및 NdeⅠ 제한효소를 이용하여 PCR- RFLP 분석을 실시하였다. Intron 6번을 포함하는 영역의 PCR 산물 크기는 2,440 bp 이었다. MspⅠ다형성은 PCR-RFLP 분석 결과 3개의 대립유전자가 존재하였으며, 한우품종에서는 3개의 대립유전자 모두가 발견되었고, CC 형태의 유전자형을 제외한 5개의 유전자형 (AA, AB, AC, BC 및 BB)을 확인하였다. Angus, Brown Swiss, Hereford, Holstein 및 Simmental 품종에서는 A 대립유전자만을 갖는 것으로 조사되었고, 한우는 44%만 AA 유전자형을 나타내었다. BsrBⅠ 다형성은 2개의 대립유전자로서 3개의 유전자형이 나타나는 것을 확인하였으며, Charo- lais 및 Hereford 품종이 다른 소 품종에 비하여 A 대립유전자의 빈도가 높게 나타났다. NdeⅠ다형성을 분석한 결과 Brown Swiss 품종에서는 NdeⅠ에 의해 절단되는 형태인 A 대립유전자만 관찰되었으며, Holstein 품종은 92%, Simmental 품종은 72%가 절단되는 형태를 나타내어, 모색이 흰색을 띠는 소 품종에서 절단되는 형태가 많았다. 소 c-KIT receptor 유전자의 intron 6번 영역에서 확인된 4개의 염기치환은 품종에 따라 다른 빈도를 보였으나, 이들 염기치환과 흰 반점과의 연관성에 대한 증거는 발견하지 못하였다. 그러므로 소의 흰 반점과 c-KIT receptor 유전자 내의 변이와의 관련성은 다른 영역에 대한 추가적인 분석과, 이미 보고된 다른 모색관련 유전자의 다형성과의 연관성 분석 등과 같은 연구가 필요한 것으로 판단된다.

We considered KIT gene as a candidate gene for the white-spotting pattern in cattle. This study was carried out to detect genetic variation of c-KIT receptor gene and to investigate association between the mutation and the white-spotting pattern in cattle. PCR-RFLP analysis within intron 6 of c-KIT receptor gene were performed with 8 cattle breeds including Hanwoo, Angus, Brown Swiss, Charolais, Hereford, Holstein, Limousin and Simmental.When PCR product of approximately 2,440 bp including intron 6 of c-KIT receptor gene was sequenced, four nucleotide substitutions were found within intron 6 of the bovine c-KIT receptor gene. In PCR-RFLP analysis, three alleles (A, B and C), two alleles (A and B) and two alleles (A and B) at each locus were identified by MspⅠ, BsrBⅠ and NdeⅠ, respectively. Although frequencies of allele at each locus were different among cattle breeds, we could not get any evidence related with white or white spotting phenotypes in these mutations on intron 6 of c-KIT receptor gene. However, we can not entirely exclude the possibility that c-KIT receptor gene is responsible for white spotting phenotype in cattle. Thus, further studies need to detect other mutations in c-KIT receptor gene and to test association of those mutations and coat color phenotypes in cattle.

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Background : Protein tyrosine kinases (PTKs) such as c-Abl, c-KIT, PDGFR-α and PDGFR-β are key proteins in the regulation of cell growth. In this study, we evaluated the correlations between the expression of c-Abl, c-KIT, PDGFR-α and PDGFR-β and the survival of patients with ovarian cancer. Methods : We performed the immunohistochemistry for 102 patients with ovarian cancer and we retrospectively reviewed the overall and disease free survival and also the response to platinum-based chemotherapy in those patients. Results : The short disease free survival rate was significantly associated with the increased expression of PDGFR-α (p= 0.0459). The short overall survival time in patients with advanced (stage III and IV) ovarian cancer was associated with the overexpression of c-Abl (p=0.0268) and the reduced expression of c-KIT (p=0.0307). On multivariate analysis, the tumor stage and c-Abl maintained their prognostic influence. Meanwhile, none of the four PTK expression patterns predicted the response to the platinum-based chemotherapy. Conclusions : Our data suggest that for patients with advanced ovarian cancer, the overexpression of c-Abl and the reduced expression of c- KIT might be used as poor prognostic factors for overall survival. It is further noteworthy that the tumor stage and c-Abl may be useful in predicting the patients’ survival. Although any of the four PTKs could not predict the response to platinum chemotherapy, the expression of the kinases targeted by tyrosine kinase inhibitor suggests the potential usefulness of imatinib mesylate for the treatment of ovarian cancer.

Background and Objectives：The proto-oncogene c-kit is a receptor tyrosine kinase recognized to initiate esential signal tra-nsduction pathways that transmit biological signals for cellular proliferation, diferentiation and metastasis. Aberrant expression -ing aditional groups of tumors that may use the stem cell factor/c-kit pathway, we investigated the expresion of c-kit in nasoph-aryngeal carcinoma. Subjects and Method：In this retrospective study, imunohistochemical stains for c-kit were performed on for-malin-fixed parafin embedded sections from 20 patients with nasopharyngeal carcinoma who were treated from 1996 to 2004. Gene mutation was analyzed by PCR-SSCP and direct sequencing. Results：c-kit over-expression was found in 65% (13/20) of patients. Eight of the 13 samples (61.5%) exhibited strongly positive immunoreactivity for c-kit protein (staining of >50% of the tumor cells). c-kit gene mutation was found in 4 of 20 cases by the PCR-SSCP method. Conclusion：c-kit protein over-expre-sion is found in 65% of the nasopharyngeal carcinoma patients. c-kit expression is corelated with c-kit DNA mutations and naso-pharyngeal carcinoma may be potential targets for treatment with imatinib mesylate. (Korean J Otolaryngol 207 ;50 :519-24)

RUNX1-RUNX1T1 양성 AML에서 c-kit 돌연변이와 골수외 백혈병의 발생은 밀접한 상관관계가 있으며 고식적 치료법에 저항성을 나타내고 궁극적으로 매우 나쁜 예후를 보인다. 그러므로 임상적으로 골수외 백혈병이 동반된 AML 환자에서 c-kit 돌연변이 여부를 확인하고 고위험군으로 분류하여 더욱 적극적인 치료를 시행해야겠다. 저자들은 최근 t (8;21) (q22;q22);RUNX1-RUNX1T1 양성 AML 환자에서 c-kit 유전자 돌연변이와 골수외 백혈병이 동반된 3예를 임상 경험하여 문헌고찰와 함께 보고하는 바이다.

t (8;21)(q22;q22) is the most frequently detected cytogenetic abnormality in patients with acute myeloid leukemia (AML) and accounts for 8-21% of de novo AML. The translocation involves two genes, RUNX1 (formerly AML1) on 21q22 and RUNX1T1 (ETO) on 8q22. RUNX1/RUNX1T1 translocation confers a favorable prognosis, but a subset of patients has a precipitous course with a high incidence of relapse. This patient subset is associated with the presence of a c-kit mutation. c-kit is a proto-oncogene, which encodes a type III transmembrane tyrosine kinase, which elicits a variety of cellular responses essential for the development of bone marrow stem cells. The expression of the c-kit mutation in AML is < 2%, whereas AML with RUNX1/RUNX1T1 shows higher rates of c-kit mutation and is associated with extramedullary leukemia and poor clinical outcome. We report cases of myeloid sarcoma in patients with RUNX1/RUNX1T1-positive AML and a c-kit mutation. (Korean J Med 2011;81:517-525)

Background : Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors in the gastrointestinal tract. Recently, many methods for the diagnosis of GIST have been developed including molecular diagnosis. Methods : We selected 90 cases of GIST that had presented at Kyungpook National University Hospital between 1998 and 2007. Tissue microarrays were made using core areas of tumor tissues. Immunohistochemical staining for c-kit, protein kinase C-theta, and platelet-derived growth factor receptor alpha (PDGFRA) was done. Direct sequencing of hot spot exonal areas for c-kit and PDGFRA were done using extracted DNAs of all 90 paraffin block tissues. Results : Among the 90 cases, 83.3% (75/90) were c-kit positive, 16.6% (15/90) were c-kit negative, 93.3% (84/90) were PDGFRA positive, and 6.6% (6/90) cases were PDGFRA negative. Fifteen cases of c-kit negative GIST included 1 case of PDGFRA negative and 5 cases of PDGFRA negative GIST were ckit positive. The one case in which both c-kit and PDGFRA were negative, showed a c-kit mutation in exon 11. Conclusions : Combined immunohistochemical staining of c-kit, discovered on GIST 1 (DOG1) and PDGFRA is helpful for the diagnosis of GIST. When all staining tests are negative for immunoreactivity, c-kit mutation analysis for exon 11, 9 should be done. Genotyping of kit and PDGFRA do not need to be examined initially, if it is only for the diagnosis of GIST.

Background : Gastrointestinal stromal tumor (GIST) is the most common non-epithelial neoplasm arising in the gastrointestinal tract. The aim of this study is to investigate the correlation among the clinicopathologic features, presence of c-kit mutation, and immunohistochemical expression of c-kit in 61 cases of GISTs. Methods : We divided the GISTs into three groups as benign, boderline and malignant, according to histologic grade. Exon 11 of the c-kit was amplified by PCR and sequenced. We performed immunohistochemical study for CD117, CD34, vimentin, SMA, desmin, and S-100 protein. Results : Twenty-one cases were diagnosed as benign GISTs, 14 cases as borderline GISTs, and 26 cases as malignant GISTs. The shape, atypia, cellularity, and necrosis showed good correlations with the histologic grades of the GISTs. Mutations of exon 11 of the c-kit were detected in 3 benign GISTs, 4 borderline GISTs, and 13 (%) malignant GISTs. Sequence analysis confirmed the deletion mutation (n=16) and the single base pair mutation (n=4). The immunohistochemical stainings showed myogenic differentiation (n=20), neurogenic differentiation (n=15), and neither myogenic or neurogenic differentiation (n=34). Conclusions : The GIST is the primitive mesenchymal tumor capable of divergent differentiation, and the mutation of the c-kit is a good parameter for the malignant GIST.

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Background : The proto-oncogene c-kit encodes a transmembrane tyrosine kinase growth factor receptor. Studies have shown that c-kit is highly expressed in normal breast epithelium, but expression is decreased in primary breast cancer. Cyclooxygenase-2 (COX-2) is an inducible enzyme that converts arachidonic acid to prostaglandins. Expression of COX-2 has been reported in malignant tumors including breast cancer. We evaluated the expression of c-kit and COX-2 in benign and malignant lesions of the breast to assess the roles of these proteins in cancer initiation and progression. Methods : We characterized 20 benign lesions, 20 intraductal carcinomas and 70 invasive breast carcinomas. Immunohistochemical staining for c-kit and COX-2 was performed. Results : Expression of c-kit was detected in 75% of the benign breast lesions, 40% of the intraductal carcinomas and 10% of the invasive carcinomas. COX-2 expression was observed in 80% of the benign lesions, 70% of the intraductal carcinomas and 52% of the invasive carcinomas. Expression of c-kit was significantly correlated with tumor size (p=0.02). COX-2 expression was significantly correlated with negative expression of estrogen receptor and progesterone receptor (p=0.02, p=0.04), Her-2/neu expression (p=0.008) and the high proliferation index (p=0.0002). Conclusions : Our results suggest that c-kit and COX-2 might be involved in malignant transformation of the mammary epithelium and tumor progression. It is suggested that c-kit and COX-2 can be used as predictive markers and therapeutic targets.

The abnormal expression of c-kit is implicated in the pathogenesis of a variety of solid tumors. The Rb pathway and p53 act as cell cycle regulators. The purpose of this study was to assess the expression of c-kit, Rb, p53, p16 and cyclin D1 and their relationship to clinical and pathological parameters in patients with non-small cell lung carcinomas (NSCLCs). Methods : Tissue microarrays consisting of 2 mm cores from the corresponding blocks were constructed from 54 NSCLCs. Immunohistochemical staining for c-kit, Rb, p53, p16 and cyclin D1 was performed. C-kit immunostaining was considered positive if ≥≥10% of tumor cells were immunoreactive along the membrane and/or in cytoplasm. For Rb, p53, p16 and cyclin D1, tumor cells showing a nuclear staining pattern were interpreted as positive. Results : We found that c-kit was expressed in 13 (24%) cases, Rb was lost in 39 (72%) cases, p53 was expressed in 28 (52%) cases, p16 was lost in 42 (78%) cases and cyclin D1 was expressed in 33 (61%) cases. The c-kit expression was significantly higher in adenocarcinoma (39%) than in squamous cell carcinoma (8%). We did not find any correlation between c-kit, Rb, p53, p16 and cyclin D1 expression and clinicopathological parameters such as: age, tumor size, lymph node involvement, disease stage and distant metastasis. There was a direct correlation between p53 expression and Rb loss. Conclusions : These results suggest that c-kit may be a useful therapeutic target for patients with c-kit positive tumors, and that the disruption of Rb and p53 pathways may play an important role in the development and progression of NSCLCs.

Background and Objectives：The proto-oncogene c-KIT encodes a receptor tyrosine kinase (KIT) whose ligand is a stem cell factor. KIT is expressed and critical for the development and growth of mast cells, melanocytes, hematopoetic stem cells, and the interstitial cells of Cajal. In this study, c-kit gene mutations were analyzed in 27 cases of NK/T cell lymphoma. Subjects and Methods：During 1995 to 2002, 27 patients with NK/T cell lymphoma in the head and neck area were selected for this study. The nasal cavity were predominant sites (15 cases), followed by 6 nasopharynx cases, 4 tonsil 4 cases, and 2 hard palate cases. Gene mutation was analyzed by PCR-SSCP and direct sequencing. Results：c-kit gene mutation was found in 5 of 27 cases by the PCR-SSCP method. Among the 5 cases, 2 cases exhibited no mutation by direct sequencing. Consequently, the mutation of c-kit gene was detected in 3 of 27 cases. Conclusion：The frequency of c-kit gene mutation (11%) indicated in the present cases is lower than that reported in north China but higher than that in Japan.

Background : Our objectives in this study were to (1) evaluate the possible role of p53, c-kit and CD34 proteins in sarcomas and to determine their potential relationship; (2) use a tissue microarray to compare the immunohistochemical staining results on both the tissue microarrays and the corresponding whole tissue sections. Methods : Whole sections from 85 sarcomas were studied for the immunohistochemical expression of p53, c-kit and CD34. Tissue microarrays consisting of triplicate 2 mm cores from the corresponding blocks were constructed and stained according to the same protocols as those used for the whole sections. Results : On whole section analysis, p53 protein was expressed in 25 cases (29.4%). Expression of c-kit was observed in 31 specimens (36.5%), whereas CD34 expression was noted in 11 tumors (12.9%). The overall concordance between triplicates was 96% (217/226). The consensus score from the combined triplicates agreed with the results on the whole sections at 91.4% (233/255). The correlations between p53 and CD34, and between c-kit and CD34, were statistically significant (p=.028 and p=.010 respectively). Conclusions : p53 and c-kit express relatively frequently in sarcomas. Tissue microarrays are an effective alternative to whole sections; however, the presence of triplicate punches seems to improve the yield but not the concordance of data.

목적 : 포유류 난포의 성장에 관여하는 기전은 밝혀져 있지 않으나, 줄기세포인자 (stem cell factor, SCF)는 난소의 성장과 발달에 관여하며, inhibin-α는 과립막세포의 분화에 관여하는 인자로 알려져 있다. 본 연구는 발달 단계에 따라 생쥐 난포 내 c-kit, 줄기세포인자 (stem cell factor, SCF)와 inhibin-α의 발현 변화를 면역조직화학적 방법을 통해 조사하여 c-kit, SCF, inhibin-α 단백질이 난포성장의 어느 시기에 발현하는지를 알아보기 위하여 시행하였다.연구 방법 : 임신 14일, 16일, 생후 2일, 7일, 그리고 21일된 생쥐 난소를 채취하여 4% paraformaldehyde에 고정한 후 c-kit/SCF, inhibin-α의 면역조직화학 염색을 실시하였다.결과 : 태자의 경우 난모세포에서 c-kit/SCF의 발현을 확인하였으며, 신생자의 경우에는 원시난포 및 일차난포의 난자에서 SCF가 발현되었다. 미성숙 생쥐의 경우 난포의 발달에 따라 난자 내 c-kit/SCF의 발현이 감소되었으며, SCF는 전동난포의 난자에서 강하게 발현되었다. Inhibin-α는 미성숙 생쥐의 전동난포 및 초기 동난포의 과립막세포에서 발현되었다.

Expression of c-Kit/SCF and Inhibin-α in Ovarian Follicles DuringMouse Development

Background: Extensive efforts have been made to investigate c-KIT expression in lung cancer specimens and its correlation with clinical outcomes, but the issue remains unresolved. Thus, this study will be conducted to clarify the prognostic value of c-KIT expression in lung cancer patients. Materials and Methods: We will search Pubmed, SCOPUS, and ISI web of sciences with no restriction of language. Studies with any design (except case reports or case series) evaluating correlations of c-KIT expression with survival or outcome in patients with lung cancer will be included. The outcome measures will include all types of survival indexes, including overall survival rate and disease free survival using Kaplan-Meier analysis and hazard ratios. Study selection and data extraction will be performed by two independent researchers. Quality assessment (assessment of risk of bias) and data synthesis will be implemented using Stata software version 11.1. Results: No ethical issues are predicted. These findings will be published in a peer-reviewed journal and presented at national and international conferences. Conclusions: This systematic review protocol is registered in the PROSPERO International Prospective Register of Systematic Reviews, registration number = CRD42015023391.

Urinary bladder squamous cell carcinoma (SCC), one of the most common neoplasms in Egypt, is attributed to chronic urinary infection with Schistosoma haematobium (Schistosomiasis). The proto-oncogene c-KIT, encoding a tyrosine kinase receptor and implicated in the development of a number of human malignancies, has not been studied so far in schistosomal urinary bladder SCCs. We therefore determined immunohistochemical (IHC) expression of c-KIT in paraffin sections from 120 radical cystectomies of SCCs originally obtained from the Pathology Department of Suez Canal University (Ismailia, Egypt). Each slide was evaluated for staining intensity where the staining extent of >10% of cells was considered positive. c-KIT overexpression was detected in 78.3% (94/120) of the patients, the staining extents in the tumor cells were 11-50% and >50% in 40 (42.6%) and 54 (57.4%) respectively. The positive cases had 14.9%, 63.8%, 21.3% as weak, moderate and strong intensity respectively. Patients with positive bilharzial ova had significantly higher c-KIT expression than patients without (95.2% vs. 38.9%, P=0.000). Mutation analysis of exons 9-13 was negative in thirty KIT positive cases. The high rate of positivity in SBSCC was one of the striking findings; However, CD117 may be a potential target for site specific immunotherapy to improve the outcome of this tumor.