Mast cells in oral lichen planus and oral lichenoid lesions related to dental amalgam contact

Abstract The aim of this study was to analyze the expression of mast cell markers toluidine blue, c-kit, and tryptase and presence of mononuclear inflammatory cells in oral lichen planus (OLP) and oral lichenoid lesions related to dental amalgam. Nineteen specimens of OLP, OLLC, and healthy oral mucosa were selected. Mononuclear inflammatory cells were analyzed. Histochemical and immunohistochemical analyses were performed using toluidine blue, anti-c-kit and anti-tryptase reagents, and the results were quantified in areas A and B of connective tissue. Mast cells of all OLP and OLLC samples were positive for toluidine blue, c-kit, and tryptase. The density of toluidine blue+, c-kit+ and tryptase+ mast cells was higher in tissue with OLP and OLLC compared with healthy controls (p < 0.05). No difference was noted in mast cells density between OLP and OLLC (p > 0.05). The density of tryptase+ mast cells was higher in the subepithelial region (area A) than the region below it (Area B) in OLLC (p = 0.047). The mononuclear inflammatory cell density was higher in OLLC compared to OLP, but without statistical significance (p > 0.05). A positive statistical correlation was found between mononuclear immune cells and density of c-kit+ and tryptase+ mast cells in OLP (r = 0.943 and r = 0.886, respectively). Our data demonstrate that the etiopathogenesis process of OLP and OLLC modulates the expansion and degranulation of mast cells; mast cells density, however, was similar between OLP and OLLC. The distribution of mast cells appears to vary along the lamina propria.

KIT genetic alterations in breast cancer.

AIMS: Activating somatic mutations or gene amplification of KIT result in constitutive activation of its receptor tyrosine kinase, which is targetable in various solid tumours. Here, we sought to investigate the presence of KIT genetic alterations in breast cancer (BC) and characterise the histological and genomic features of these tumours. METHODS: A retrospective analysis of 5,575 BCs previously subjected to targeted sequencing using the FDA-authorised Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Targets (MSK-IMPACT) assay was performed to identify BCs with KIT alterations. A histological assessment of KIT-altered BCs was conducted, and their repertoire of genetic alterations was compared with that of BCs lacking KIT genetic alterations, matched for age, histological type, oestrogen receptor/HER2 status and sample type. RESULTS: We identified 18 BCs (0.32%), including 9 primary and 9 metastatic BCs, with oncogenic/likely oncogenic genetic alterations affecting KIT, including activating somatic mutations (n=4) or gene amplification (n=14). All KIT-altered BCs were of high histological grade, although no distinctive histological features were observed. When compared with BCs lacking KIT genetic alterations, no distinctive genetic features were identified. In two metastatic KIT-altered BCs in which the matched primary BC had also been analysed by MSK-IMPACT, the KIT mutations were found to be restricted to the metastatic samples, suggesting that they were late events in the evolution of these cancers. CONCLUSIONS: KIT genetic alterations are vanishingly rare in BC. KIT-altered BCs are of high grade but lack distinctive histological features. Genetic alterations in KIT might be late events in the evolution and/or progression of BC.

Presença de mutações no gene BRAF e outros oncogenes e associação com características clínicas e epidemiológicas em pacientes com melanoma metastático / Presence of risk in the BRAF gene and other oncogenes and association with clinical and epidemiological characteristics in patients with metastatic melanoma

Embora o melanoma seja representado por apenas cerca de 5% dos casos de tumores malignos de pele, é responsável pela ampla maioria de óbitos relacionados a tumores cutâneos. Seu desenvolvimento está principalmente associado à presença de mutações em oncogenes específicos, como BRAF, c-KIT e PDGFRA, os quais estão relacionados ao metabolismo celular. OBJETIVOS: Avaliar retrospectivamente a presença de mutações nos genes BRAF (éxons 15), C-KIT (éxons 9,11,13 e 17) e PDGFRA (éxons 12 ,14 e 18) e correlacionar os resultados com as características clínicas e epidemiológicas e desfecho dos pacientes. METODOLOGIA: Foi realizado um estudo retrospectivo de 94 pacientes com melanoma metastático atendidos no Hospital Amaral Carvalho entre os anos de 2015 a 2022, de acordo com as seguintes variáveis: idade ao diagnóstico, gênero, cor, local do tumor primário, local de metástase, subtipo histológico de melanoma, dosagem de LDH, positividade para marcadores de imuno-histoquímica, espessura, presença de ulceração, metástase no linfonodo ao diagnóstico do tumor primário, espessura Breslow, classificação Clark, índice mitótico e desfecho (óbito, sobrevida). RESULTADOS: A maioria dos pacientes eram do sexo masculino (52,1%), de cor branca (97,9%) e com idade acima de 60 anos (42,5%). O subtipo histológico mais encontrado foi o extensivo superficial (42,5%), sendo os membros inferiores o local mais acometido (35,1%). O nível IV de Clark (39,4%) e índice de Breslow acima de 4mm (33,0%) foram os mais prevalentes. A maior parte dos tumores não apresentou ulceração (53,2%) e mais da metade dos pacientes apresentou mais de uma mitose por mm² (47,9%). A dosagem de desidrogenase láctica (LDH) se manteve dentro da normalidade na maioria dos pacientes no momento do diagnóstico (43,6%) e no surgimento de metástases (30,9%). Todos os pacientes apresentaram ao menos uma metástase, sendo os linfonodos regionais o local de maior incidência. A maioria dos pacientes faleceu em decorrência da doença (66,0%). A análise de BRAF apresentou significância estatística para as variáveis idade ao diagnóstico (p= 0,0085), tipo histológico (p= 0,048) e nível de Clark (p= 0,0290). A mediana de sobrevivência para pacientes com mutações em BRAF foi de 62 meses e 50 meses para aqueles que não apresentaram mutações. Não foram encontradas significâncias estatísticas entre c-KIT e as variáveis analisadas. A mediana de sobrevivência para pacientes com mutações em c-KIT foi de 38 meses e 70 meses para aqueles que não apresentaram mutações. CONCLUSÕES: A presença de mutação em BRAF esteve associada à menor idade e menores índices de Clark, e relacionada à ligeira maior sobrevida. O contrário foi observado para mutações em c-KIT, apesar da ausência de significância estatística: uma ligeira menor sobrevida foi observada em pacientes mutados. O LDH não esteve bem correlacionado à presença do melanoma metastático ao se apresentar normal na maioria dos casos. Grande parte dos pacientes tiveram o tumor primário localizado nos membros inferiores, diferentemente do relatado por outros estudos, e apesar de não significante, os tumores de tronco foram em sua maioria mutados para BRAF, e o oposto observado em membros inferiores e superiores. Assim, o papel prognóstico da mutação em BRAF na progressão da doença é ainda controverso. Tais dados podem fornecer mais informações para a adequação de protocolos de prevenção e tratamento de pacientes acometidos por melanoma.

INTRODUCTION: Although melanoma is represented by only about 5% of cases of malignant skin tumors, it is responsible for the vast majority of deaths related to skin tumors. Its development is mainly associated with the presence of mutations in specific oncogenes, such as BRAF, c-KIT and PDGFRA, which are related to cell metabolism. OBJECTIVES: Retrospectively evaluate the presence of mutations in BRAF (exons 15), C-KIT (exons 9,11,13 and 17) and PDGFRA (exons 12, 14 and 18) genes and correlate the results with the clinical and epidemiological characteristics and patient outcomes. METHODS: A retrospective study of 94 patients with metastatic melanoma treated at Hospital Amaral Carvalho between the years 2015 to 2022 was carried out, according to the following variables: age at diagnosis, gender, color, site of primary tumor, site of metastasis, histological subtype of melanoma, LDH dosage, positivity for immunohistochemical markers, thickness, presence of ulceration, lymph node metastasis at diagnosis of the primary tumor, Breslow thickness, Clark classification, mitotic index and outcome (death, survival). RESULTS: Most patients were male (52.1%), white (97.9%) and aged over 60 years (42.5%). The most common histological subtype was superficial extensive (42.5%), with the lower limbs being the most affected site (35.1%). Clark's level IV (39.4%) and Breslow thickness above 4mm (33.0%) were the most prevalent. Most tumors did not show ulceration (53.2%) and more than half of the patients had more than one mitosis per mm² (47.9%). The lactate dehydrogenase (LDH) dosage remained within the normal range in most patients at the time of diagnosis (43.6%) and at the onset of metastases (30.9%). All patients had at least one metastasis, with regional lymph nodes being the site with the highest incidence. Most patients died as a result of the disease (66.0%). BRAF analysis showed statistical significance for the variables age at diagnosis (p= 0.0085), histological type (p= 0.048) and Clark's level (p= 0.0290). Median survival for patients with BRAF mutations was 62 months and 50 months for those without mutations. No statistical significance was found between c-KIT and the analyzed variables. The median survival for patients with c-KIT mutations was 38 months and 70 months for those without mutations. CONCLUSIONS: The presence of a BRAF mutation was associated with younger age and lower Clark scores, and related to slightly longer survival. The opposite was observed for mutations in c-KIT, despite the absence of statistical significance: a slightly lower survival was observed in mutated patients. LDH was not well correlated with the presence of metastatic melanoma as it was normal in most cases. Most of the patients had the primary tumor located in the lower limbs, unlike what has been reported by other studies, and although not significant, the trunk tumors were mostly mutated to BRAF, and the opposite was observed in the lower and upper limbs. Thus, the prognostic role of the BRAF mutation in disease progression is still controversial. Such data may provide more information for the adequacy of prevention and treatment protocols for patients affected by melanoma.

Gastrointestinal stromal tumors: a comprehensive radiological review.

Gastrointestinal stromal tumors (GISTs) originating from the interstitial cells of Cajal in the muscularis propria are the most common mesenchymal tumor of the gastrointestinal tract. Multiple modalities, including computed tomography (CT), magnetic resonance imaging (MRI), fluorodeoxyglucose positron emission tomography, ultrasonography, digital subtraction angiography, and endoscopy, have been performed to evaluate GISTs. CT is most frequently used for diagnosis, staging, surveillance, and response monitoring during molecularly targeted therapy in clinical practice. The diagnosis of GISTs is sometimes challenging because of the diverse imaging findings, such as anatomical location (esophagus, stomach, duodenum, small bowel, colorectum, appendix, and peritoneum), growth pattern, and enhancement pattern as well as the presence of necrosis, calcification, ulceration, early venous return, and metastasis. Imaging findings of GISTs treated with antineoplastic agents are quite different from those of other neoplasms (e.g. adenocarcinomas) because only subtle changes in size are seen even in responsive lesions. Furthermore, the recurrence pattern of GISTs is different from that of other neoplasms. This review discusses the advantages and disadvantages of each imaging modality, describes imaging findings obtained before and after treatment, presents a few cases of complicated GISTs, and discusses recent investigations performed using CT and MRI to predict histological risk grade, gene mutations, and patient outcomes.

Effect of C-KIT gene mutation on the prognosis of acute myeloid leukemia associated with core-binding factor in children: a Meta-analysis / 白血病·淋巴瘤

Objective:To systematically evaluate the relationship between C-KIT gene mutation and the prognosis of childhood core-binding factor-related acute myeloid leukemia (CBF-AML).Methods:The PubMed database was searched with "KIT" "Acute Myeloid Leukemia" and "Children"; the Chinese Journal Full-text Database (CNKI), Chinese Biomedical Literature Database (CBM), VIP database and Wanfang database were also searched with "KIT" "Acute Myeloid Leukemia" and "Children", and the search time was from the establishment of the database to October 1, 2020. After strict screening, the literature was included in the analysis; according to the presence or absence of genetic changes, the included cases was divided into C-KIT mutation group and wild group, and the complete remission (CR) rate, event-free survival (EFS) rate, and overall survival (OS) rate of the two groups were analyzed.Results:Six articles were collected, including 4 articles in English and 2 articles in Chinese, with a total of 667 patients. There was a statistically significant difference in the EFS rate between the C-KIT mutation group and wild group in children with CBF-AML ( HR = 2.40, 95% CI 1.47-3.89, P = 0.001); there was no significant difference in the CR rate and OS rate ( OR = 0.93, 95% CI 0.48-1.80, P = 0.830; HR = 1.92, 95% CI 0.96-3.83, P = 0.065) between the two groups. Conclusions:C-KIT gene mutation may be a risk factor for poor prognosis in children with CBF-AML.

Clinicopathological Features and Outcomes of Gastrointestinal Stromal Tumours in Oman: A multi-centre study.

OBJECTIVES: This study aimed to report the clinicopathological features, management and long-term outcomes of patients with gastrointestinal stromal tumours (GISTs) in Oman. METHODS: This retrospective study was conducted on patients treated for GIST between January 2003 and December 2017 at three tertiary referral centres in Muscat, Oman. All patients with confirmed histopathological diagnoses of GIST and followed-up at the centres during this period were included. Relevant information was retrieved from hospital records until April 2019. RESULTS: A total of 44 patients were included in the study. The median age was 55.5 years and 56.8% were female. The most common primary site of disease was the stomach (63.6%) followed by the jejunum/ileum (18.2%). Two patients (4.5%) had c-Kit-negative, discovered on GIST-1-positive disease. A total of 24 patients (54.5%) presented with localised disease and eight (33.3%) were classified as being at high risk of relapse. Patients with metastatic disease received imatinib in a palliative setting, whereas those with completely resected disease in the intermediate and high-risk groups were treated with adjuvant imatinib. Of the six patients (13.6%) with progressive metastatic disease, of which four had mutations on exon 11 and one on exon 9, while one had wild-type disease. Overall, rates of progression-free survival and overall survival (OS) at 100 months were 77.4% and 80.4%, respectively. Rates of OS for patients with localised and metastatic disease were 89.9% and 80.2%, respectively. CONCLUSION: The presenting features and outcomes of patients with GISTs in Oman were comparable to those reported in the regional and international literature.

[Jejunal gastrointestinal stromal tumor (GIST): clinical case]. / Tumor del estroma gastrointestinal (GIST) de yeyuno: caso clínico.

Background: Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. It is exposed a clinical case of jejunal GIST from a second-level hospital in Mexico. Clinical case: Female patient of 76 years, with history of tobacco use (two cigarettes per day for 25 years), that is referred to General Surgery due to a four month evolution of symptoms, characterized by abdominal pain, hyporexia and urinary symptomatology. Physical examination revealed a non-pulsatile, solid, non-mobile, non-painful mass in the hypogastrium and right iliac fossa of approximately 15 cm in length. Ovarian tumor was ruled out, since CEA and CA-125 tumor markers were negative. Abdominopelvic ultrasound was performed and reported a solid tumor with cystic spaces inside. CT reported a solid tumor of 9.5 x 2.5 x 8.3 cm, with defined edges, multilobed, presence of some calcifications in its wall that did not show enhancement with the use of contrast media. Patient underwent exploratory laparotomy and it was found a jejunal tumor, 210 cm from the ligament of Treitz. Immunohistochemistry reported positivity to KIT and DOG1, confirming the diagnosis of GIST. Conclusion: GISTs are uncommon entities. Their clinical presentation is insidious and the preoperative diagnosis is complex due to the need for biopsy. The treatment is surgery, but tyrosine kinase inhibitors should be administered. Even in patients with response to treatment, follow-up is mandatory due to the risk of recurrence.

Introducción: los tumores del estroma gastrointestinal (GIST) son los tumores mesenquimatosos más comunes del tracto gastrointestinal. Se expone un caso clínico de GIST en yeyuno que se presentó en un hospital de segundo nivel en México. Caso clínico: femenino de 76 años, con antecedente de tabaquismo (dos cigarros diarios durante 25 años), referida a Cirugía General por cuadro de cuatro meses de evolución (dolor abdominal tipo cólico en hipogastrio, hiporexia y sintomatología urinaria). A la exploración física, se le detectó tumor no pulsátil, sólido, no móvil, no doloroso, adherido a planos profundos en hipogastrio y fosa ilíaca derecha de aprox. 15 cm de longitud. Se descartó tumor ovárico al resultar negativos los marcadores tumorales ACE y CA-125. Se realizó ultrasonido abdominopélvico que reportó imagen de tumoración sólida con zonas quísticas en su interior. La TC reportó tumoración sólida, de bordes definidos, multilobulada con algunas calcificaciones milimétricas en su pared de 9.5 x 2.5 x 8.3 cm y sin realce al administrar medio de contraste. La paciente se sometió a laparotomía exploradora y se encontró tumoración adherida a yeyuno a 210 cm del ligamento de Treitz. El tumor fue positivo a KIT y DOG1, lo que confirmó el diagnóstico de GIST de patrón fusiforme. Conclusión: los GIST son poco frecuentes. Su presentación clínica es insidiosa y el diagnóstico preoperatorio es complejo debido a la toma de biopsia. El tratamiento continúa siendo la cirugía, pero se deben administrar inhibidores de la tirosina cinasa. Incluso en pacientes con respuesta favorable al tratamiento, se recomienda seguimiento por riesgo de recidiva.

A comparison between cDNA and DNA samples for the detection of c-KIT exon 17 mutation in acute myeloid leukemia patients / 中华检验医学杂志

Objective To investigate the impact of sample typeon the detection of c-KIT exon 17 mutation in acute myeloid leukemia (AML) patients. Methods A retrospective study was conducted on 51 bone marrow samples collected from 37 AML patients [17 maleand 20 female, with a median age of 33 (range from 1 to 82)] at diagnosis or after treatment from June 2016 to August 2018. Of the 37 cases of AML, 24 were t(8; 21) AML, 11 were inv(16)/t(16;16) AML and 2 were non-CBF-AML. RNA and DNA were simultaneously extracted from every sample. PCR followed by Sanger sequencing were used to screen c-KIT exon 17 mutation, and the comparisons were made between paired cDNA and DNAsamples. Results (1) Of the 51 paired samples, 14 pairs were simultaneously detected positive for c-KITmutation in both of cDNA and DNA samples, but 17 pairs were detected negative in both, and the remaining 20 pairswere only detected positive for the mutation in cDNA but not in DNA, with an inconsistency rate of 39.2％. The positive rate of detecting c-KITmutation was significantly higher in cDNA than in DNA samples (66.7％vs 27.5％,P=0.000073). (2)Inconsistent mutation results between paired cDNA and DNA samples occurred in t(8;21)AML, inv(16)AML and non-CBF-AML patients with the inconsistency rate of 36.4％(12/33), 27.2％(3/11) and 71.4％ (5/7), respectively. (3)The inconsistency rate was significantly higher in samples collected after treatment compared with those collected at diagnosis (72.7％vs 13.8％, P=0.00003). (4) All 5 serially monitored patients with c-KITmutation had inconsistency in mutation detection between cDNA and DNA samples during follow up. Conclusion cDNA improves the detection of c-KIT exon 17 mutation in AML patients compared with DNA, which is especially common after treatment.

No detection of c-kit gene mutations in exons 9, 11, 13 and 17 and low CD117 expression in plaque-stage mycosis fungoides

Abstract: The growth factor receptor c-kit (CD117) is expressed in immature T-cells and in some advanced forms of mycosis fungoides. c-kit gene mutation results in unrestricted neoplastic proliferation. We aimed to detect by PCR the most frequent exon mutations in seventeen plaque-stage MF patients, in their perilesional skin and in healthy skin donors. We secondarily evaluated CD117 expression by immunohistochemistry in plaque-stage and tumor-stage MF. We detected no mutation in c-kit gene and low CD117 expression was confirmed on atypical cells in one patient. Complete c-kit exon and intron sequences should be assessed and more sensitive sequencing method could be also applied.

Insights from molecular signature of in vivo cardiac c-Kit(+) cells following cardiac injury and ß-catenin inhibition.

There is much interest over resident c-Kit(+) cells in tissue regeneration. Their role in cardiac regeneration has been controversial. In this study we aim to understand the in vivo behavior of cardiac c-Kit(+) cells at baseline and after myocardial infarction and in response to Sfrp2. This approach can accurately study the in vivo transcript expressions of these cells in temporal response to injury and overcomes the limitations of the in vitro approach. RNA-seq was performed with c-Kit(+) cells and cardiomyocytes from healthy non-injured mice as well as c-Kit(+) cells from 1 day post-MI and 12 days post-MI mice. When compared to in vivo c-Kit(+) cells isolated from a healthy non-injured mouse heart, cardiomyocytes were enriched in transcripts that express anion channels, cation channels, developmental/differentiation pathway components, as well as proteins that inhibit canonical Wnt/ß-catenin signaling. Myocardial infarction (MI) induced in vivo c-Kit(+) cells to transiently adopt the cardiomyocyte-specific signature: expression of a number of cardiomyocyte-specific transcripts was maximal 1 day post-MI and declined by 12 days post-MI. We next studied the effect of ß-catenin inhibition on in vivo c-Kit(+) cells by administering the Wnt inhibitor Sfrp2 into the infarct border zone. Sfrp2 both enhanced and sustained cardiomyocyte-specific gene expression in the in vivo c-Kit(+) cells: expression of cardiomyocyte-specific transcripts was higher and there was no decline in expression by 12 days post-MI. Further analysis of the biology of c-Kit(+) cells identified that culture induced a significant and irreversible change in their molecular signature raising questions about reliability of in vitro studies. Our findings provide evidence that MI induces in vivo c-Kit(+) cells to adopt transiently a cardiomyocyte-specific pattern of gene expression, and Sfrp2 further enhances and induces sustained gene expression. Our approach is important for understanding c-Kit(+) cells in cardiac regeneration and also has broad implications in the investigation of in vivo resident stem cells in other areas of tissue regeneration.

Evaluation of the relationship between c-Kit expression and mean platelet volume in classic Kaposi's sarcoma

Abstract: Background: c-Kit is a proto-oncogene that encodes tyrosine kinase receptor (CD117). Mean platelet volume (MPV) is a useful marker, providing information on platelet function and diameter. Objective: To investigate c-Kit expression and intensity in patients with Kaposi's sarcoma (KS) and to investigate the relation between Ki-67 proliferation and MPV. Methods: A total of 32 patients, diagnosed with classic cutaneous KS, were included in this study. We reevaluated the histopathological reports with the preparations, confirmed the diagnosis and then determined the patients' histopathological stages. c-Kit expression and Ki-67 proliferation were investigated immunohistochemically in KS cases, while MPV in all cases was checked. Results: Although c-Kit expression was detected in 22 cases (68.8%), it was not expressed in 10 cases (31.2%). We detected 8 cases with + (25%), 6 with ++ (18.8%) and 8 with +++ (25%). Ki-67 expression was 5.0% (min-max 1.0-20.0). Relapse was observed in 5 cases (15.6%) out of 32. There was positive correlation between c-Kit expression and MPV (rs=0.598, p<0.001), and between c-Kit intensity and MPV (rs=0.588, p<0.001). Conclusion: c-Kit is highly positive in KS. c-Kit positivity indicates a high risk of tumor growth, invasion and relapse. Furthermore, c-Kit expression stimulates megakaryocytes to release young and large thrombocytes into the periphery. Thus, high MPV, c-Kit expression and immunostaining intensity indicate high invasion and relapse in KS subjects.

Comparison of c-Kit expression between primary and metastatic melanoma of skin and mucosa.

BACKGROUND: Melanoma causes the greatest morbidity and mortality of all skin cancers. Mucosal melanoma is a rare but highly aggressive neoplasm. According to previous studies the prevalence of KIT mutations in acral lentiginous and mucosal melanomas is relatively low (less than 15-20%), but it can have profound therapeutic implications for localized high risk or metastatic diseases. Our goal was to evaluate c-Kit expression in different types of primary and metastatic melanoma to discriminate potential candidates for targeted therapy. METHODS: We designed a cross-sectional study and selected 50 cases of malignant melanoma (primary, metastatic cutaneous, and mucosal) from the affiliated hospitals of Shiraz University of Medical Sciences in the period of 2008 to 2012. Immunohistochemistry for KIT expression was performed. Multistage sampling method was selected for sampling and chi-square test was used for statistical analysis. RESULTS: In our study, male to female ratio was 1.77. The male sex was correlated with higher tumor stage (p< 0.05). 62% (n= 31) of cases showed at least 5% of KIT-positive cells, consist of 18% (n= 9) with 5-50%, 16% (n= 8) with 51-95%, and 28% (n= 14) of cases showed more than 95% of cells expressing KIT. But in 38% (n= 19) of cases KIT expression was less than 5% of positive cells. Tumor stage was positively correlated with tumor cell immunoreactivity and intensity (p< 0.05). Metastatic melanoma showed lower percentage (43%) of positivity. Intensity of staining and percentage of positive cells were positively correlated (p< 0.001). CONCLUSION: In primary melanomas, significant KIT expression was found by immunohistochemistry, which may be useful to screen the patients for advising to KIT mutation analysis and targeted therapy.

Effect of curcumin on the activity and migration of as well as c-kit mRNA expression in melanocytes / 中华皮肤科杂志

Objective To explore the effect of curcumin on the activity and migration of as well as c-kit mRNA expression in melanocytes.Methods Human epidermal melanocytes were isolated from the prepuce in adolescents and subjected to primary culture.To estimate the effect of curcumin on the proliferative activity of melanocytes, some melanocytes were randomly divided into several groups to be cultured in the MelM-2 medium with or without the presence of 5, 10, 20 or 30 μmol/L curcumin, the MelM-2 medium containing curcumin of 5-30 μmol/L served as the drug control groups, and the MelM-2 medium without curcumin served as the blank control group.After 24 and 48 hours of culture, MTS assay was performed to evaluate the proliferative activity of melanocytes.Some cultured melanocytes were randomly divided into 4 groups to be cultured in the MelM-2 medium with 0, 5, 10 and 20 μmol/L curcumin respectively for 48hours.Then, wound scratch assay was conducted to estimate the migratory activity of melanocytes, and real-time fluorescence-based quantitative PCR to quantify the mRNA expression of c-kit in melanocytes.Statistical analysis was carried out by factorial design analysis of variance (ANOVA), one-way ANOVA and least significant difference (LSD)-t test.Results The proliferative activity of melanocytes was significantly decreased at 24 and 48 hours in the 30-μmol/L curcumin group compared with the negative control group (0.783 ± 0.053 vs.1.000 ± 0.018 at 24 hours, 0.637 ± 0.015 vs.0.993 ± 0.064 at 48 hours, both P ＜ 0.05), while no significant differences were observed between the other curcumin groups and the negative control group (all P ＞ 0.05).The 48-hour treatment with curcumin could significantly inhibit the migration of melanocytes in the 5-, 10-and 20-μmol/L curcumin groups compared with the control group (all P ＜ 0.05).The mRNA expression level of c-kit was also significantly reduced at 48 hours in the 5-, 10-and 20-μmol/L curcumin groups compared with the control group (1.799 ± 0.372, 1.539 ± 0.224 and 1.026 ± 0.038 vs.3.371 ± 0.352, all P ＜0.05).Conclusion Curcumin at low concentrations (≤ 20 μmol/L) has no obvious cytotoxicity against melanocytes, but can inhibit the migration of and c-kit mRNA expression in melanocytes, while curcumin at 30 μmol/L can promote the apoptosis of melanocytes.

Avaliação anatomoclínica e molecular do melanoma cutâneo em pacientes jovens (idade 18-30 anos) / Clinicopathologic and molecular evaluation of cutaneous melanoma in young patients (age 18-30)

A incidência do melanoma cutâneo em pacientes adultos jovens tem aumentado consideravelmente nos últimos anos. Há, contudo, carência de conhecimentos clinicopatológicos e moleculares sobre os melanomas que ocorrem nessa faixa etária. O presente estudo teve por objetivo avaliar 132 casos de melanoma cutâneo primário em pacientes com idade entre 18 e 30 anos, com ênfase no estudo das características clínicas, histopatológicas e avaliação molecular das mutações nos genes BRAF, NRAS e KIT. Em relação aos achados clínicos e histopatológicos, houve predomínio de indivíduos do sexo feminino (61,4%), sendo o tronco o sítio anatômico mais comumente envolvido (44,3%) e o melanoma extensivo superficial o tipo histológico predominante (79,5%). A mutação V600E no gene BRAF (BRAFV600E) foi analisada em 93 casos, utilizando-se a técnica de RT-PCR. Essa mutação foi identificada em 38,7% (36/93) e, estatisticamente, associada à fase vertical de crescimento (p = 0,01), infiltrado inflamatório discreto (p = 0,02) e presença de mitose intradérmica (p = 0,004). Houve, ainda, forte indício de associação com a presença de ulceração (p = 0,05). Todas essas variáveis apresentaram associação com pior prognóstico do melanoma cutâneo. Observou-se predomínio da mutação BRAFV600E em regiões anatômicas relacionadas à exposição solar intermitente. Nenhum caso de melanoma com fenômeno de regressão apresentou mutação BRAFV600E (p < 0,05). Não houve associação significativa entre BRAFV600E e sexo, tipo histológico, nível de Clark, índice de Breslow, elastose solar, invasão angiolinfática e perineural, satelitose, nevo melanocítico coexistente e sobrevida. A pesquisa de mutações NRAS, pela técnica de RT-PCR, detectou frequência de 3,95% (3/76). As três mutações encontradas foram do tipo 61K e ocorreram em pacientes do sexo masculino e em região de cabeça e pescoço. As mutações BRAFV600E e NRAS, quando presentes, eram mutuamente exclusivas. A frequência de mutações KIT, analisadas por...

The incidence of cutaneous melanoma in young adults has dramatically increased in recent years. However, there is scarce data about the clinicopathological and molecular characteristics on the melanomas occurring at this age group. The present study aimed to evaluate 132 patients aged between 18 and 30 years with primary cutaneous melanoma with emphasis on the study of clinical, histopathological characteristics and molecular evaluation of mutations in BRAF, NRAS and KIT genes. Regarding the clinical and histopathological findings, the following results were found: female predominance (61.4%), trunk was the most commonly anatomical site involved (44.3%) and superficial spreading melanoma, was the most common histological type (79.5 %). The V600E mutation in BRAF (BRAFV600E) gene was analyzed in 93 cases, using RT-PCR. It was present in 38.7% (36/93) and statistically related to the vertical growth phase (p = 0.01), mild inflammatory infiltration (p = 0.02) and the presence of intradermal mitosis (p = 0.004). There was, also, strongly evidence of an association with the presence of ulceration (p = 0.05). Worse prognosis was associated with these variables. There was a predominance of BRAFV600E mutation in anatomical regions related to intermittent sun exposure. No cases of melanoma with BRAFV600E mutation showed regression phenomenon (p < 0.05). There was no significant association between BRAFV600E and gender, histological type, Clark level, Breslow thickness, solar elastosis, angiolymphatic and perineural invasion, sattelitosis, coexisting melanocytic nevus and survival. The presence of a mutation in NRAS, by RT-PCR was seen in 3.95% (3/76) of the cases. All these three mutations were of type 61K, occurred in male patients and the head and neck region. BRAFV600E and NRAS mutations, when present, were mutually exclusive. The frequency of KIT mutations, analyzed by sequencing, was 11.1% (3/27). The three mutations identified in this gene were located in...

Preliminary recognition of stem cells surface markers in hepatoblastoma / 重庆医学

Objective To preliminarily screen the neoplastic stem cell (NSC) related surface markers combination and to under-stand the NSC distribution in hepatoblastoma(HB) .Methods The children cases of HB undergone the surgical therapy in the Jian-gxi Provincial Children′s Hospital were selected .The immunohistochemical method was adopted for observing the expression and distribution of NSC-related markers CD34 ,Thy-1 ,c-kit ,CD56 and stem cell factor(SCF) in the HB tissue and the normal hepatic tissue away from the edge of tumor tissue 3cm outside .Results Thy-1 and c-kit were sporadically distributed in the HB tissue and mainly focued on the portal area ,but did not exressed in the normal liver tissue ;the expression of CD34 and SCF in HB was signifi-cantly higher than that in the normal liver tissue(P0 .05) .Conclusion The different NSC related surface markers are distributed in the HB tissue and focus on the specific areas .The positive cells of Thy-1/c-kit expression may play a role in the HB occurrence .

Expression of hypoxia-inducible factor-1α in acral malignant melanoma tissue / 中华皮肤科杂志

Objective To measure the expression of hypoxia-inducible factor (HIF)-1α in acral malignant melanoma (MM) tissue and to investigate its relationship with the stem cell factor (SCF)/c-kit pathway.Methods Immunohistochemical staining was performed to measure the expression of HIF-1α in tissue specimens from lesions of 93 patients with acral MM,21 with non-acral MM,39 with acral melanocytic nevi,and from the normal acral skin of 15 healthy human controls.Meanwhile,the expression of c-kit was detected by immunohistochemical staining in the 93 acral MM tissue specimens.Statistical comparisons were carried out by chi-square test and Mann-Whitney U test.The relationship of HIF-1α expression with c-kit expression as well as tumor progression and staging was assessed by Spearman correlation analysis.Results Immunohistochemistry showed that the expression rate of HIF-1α was 87.10％ (81/93) in acral MM specimens,90.48％ (19/21) in non-acral MM specimens,15.38％ (6/39) in acral melanocytic nevus specimens,but 0 (0/15) in the normal acral skin specimens.The expression of HIF-1α was significantly higher in acral MM lesions than in normal acral skin and acral melanocytic nevus lesions (both P ＜ 0.01),and significantly different between acral MM and non-acral MM lesions (P ＜ 0.01).Moreover,HIF-1α expression was positively correlated with Clark level and Breslow depth of melanoma (rs =0.442,0.368,respectively,both P ＜ 0.01),with the progression of acral MM (from in situ to aggressive and metastatic MM) (rs =0.420,P ＜ 0.01),and with the expression of c-kit (rs =0.307,P ＜ 0.01).Conclusions HIF-1α is highly expressed in acral MM,positively correlated with the staging,progression and aggression of MM,and co-expressed with c-kit in acral MM tissue,suggesting that both HIF-1α and c-kit take part in the pathogenesis of acral MM.

Effect of ferulic acid on the proliferation of, as well as melanin synthesis, tyrosinase activity and expressions of c-kit and ERK proteins in keratinocytes / 中华皮肤科杂志

Objective To evaluate the in vitro effect of ferulic acid on the proliferation of,as well as melanin synthesis,tyrosinase activity and expressions of c-kit and ERK proteins in cultured normal human epidermal melanocytes.Methods Cultured normal human epidermal melanocytes were treated with various concentrations of ferulic acid for different durations,and those remaining untreated served as the control.Then,3-(4,5-dimethylthiazol2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium,inner salt (MTS) assay was performed to estimate cell proliferative activity at 24,48 and 72 hours,sodium hydroxide solubilization method to quantify melanin content in melanocytes at 72 hours,dopa oxidation assay to evaluate tyrosinase activity at 72 hours,Western blot to measure the expressions of c-kit and ERK1/2 proteins at 72 hours.Results Cellular proliferative activity was significantly inhibited in melanocytes treated with ferulic acid of 0.01,0.1 and 1 mg/ml for 24,48 and 72 hours compared with untreated melanocytes (all P ＜ 0.05),and the 72-hour treatment with ferulic acid of 1 mg/ml showed the strongest inhibitory effect.Ferulic acid at 0.01,0.1 and 1 mg/ml all markedly suppressed melanin synthesis and tyrosinase activity,decreased the expressions of c-kit and ERK1/2 proteins in melanocytes,with significant differences in these parameters between ferulic acid-treated and untreated melanocytes (all P ＜ 0.05).Conclusions Ferulic acid could downregulate the proliferation of,as well as melanin synthesis,tyrosinase activity,and expressions of c-kit and ERK proteins in cultured human epidermal melanocytes.

Expression and diagnostic significance of DOG1, CD117 and CD34 in gastrointestinal stromal tumors / 中国医师杂志

Objective To investigate the expression and diagnostic significance of DOG1,CD117and CD34 in gastrointestinal stromal tumors.Methods Expressions of DOG1,CD117 and CD34 were determined by immunohistochemical techniques (EnVision) in 60 cases of gastrointestinal stromal tumors (GIST) and 14 cases of other mesenchymal tumors.Results Expression of DOG1 in GIST was significantly higher than in other mesenchymal tumors (P =0.000).Expression of DOG1 in GIST from stomach was significantly higher than that from intestines.The expression rates of DOG1,CD117 and CD34 in GIST were 95％,95％,and 83.3％,respectively.Expression of DOG1 was significantly higher than CD34 (P =0.040),but no significant difference between DOG1 and CD117 (P =1.000).The expression rates of DOG1 in CD117-positive,CD34-positive tumors were 94.7％ and 94.1％,respectively.All the CD117-negative,CD34-negative tumors expressed DOG1,3 cases which were negative for CD117 and CD34 expressed DOG1.Conclusions DOG1 is a novel marker for GIST,It is necessary to the combined detection of the expression of DOG1,CD117 and CD34,which will further improve the diagnostic accuracy of GIST.

Effect of tacalcitol on the proliferation, adhesion, migration and c-kit mRNA expression of human epidermal melanocytes / 中华皮肤科杂志

Objective To evaluate the effect of tacalcitol on the proliferation,adhesion,migration and c-kit mRNA expression of cultured human epidermal melanocytes.Methods Cultured epidermal melanocytes from the prepuce of adolescent males were treated with various concentrations of tacalcitol.Then,cell proliferation was evaluated by tetrazolium salt (XTT) assay after 24,48 and 72 hours of treatment,adhesive activity by using fibronectin-coated culture plates after 72 hours,migratory activity by Transwell assay using a microporous membrane after 24 hours,and the c-kit mRNA expression was semiquantitatively analyzed by reverse transcription PCR after 72 hours of treatment.Statistical analysis was done by repeated-measure analysis of variance and completely random design analysis of variance.Results As repeated-measure analysis of variance showed,tacalcitol of 10-10,10-9,10-8,10-7 and 10-6 mol/L significantly promoted the proliferation of melanocytes (F =9.47,P ＜ 0.01),with significant differences in the promoting effect among various durations of treatment with different concentrations of tacalcitol (F =14.44,P ＜ 0.01),and with significant interaction effect between drug concentration and treatment duration (F =2.47,P ＜ 0.01).The highest proliferation level was observed in melanocytes treated with tacalcitol of 10-s mol/Lfor 72 hours.There was a significant increase in the adhesion rate of human epidermal melanocytes to fibronectin after treatment with tacalcitol of 10-8-10-7 mol/L for 72 hours (both P ＜ 0.01),number of melanocytes migrating through micropore membranes per high-power field (× 200) after treatment with tacalcitol of 10-9-10-8 mol/L for 24 hours (both P ＜ 0.01),and in the c-kit mRNA expression in melanocytes treated with tacalcitol of 10-9-10-7mol/L for 72 hours (all P ＜ 0.01).Conclusion Tacalcitol can promote melanocytes to proliferate,migrate,express c-kit mRNA,and adhere to fibronectin.

Screening of C-kit gene Mutation in Acute Myeloid Leukaemia in Northern India.

BACKGROUND: Acute Myeloid Leukaemia (AML) is a cancer of blood-forming cells in bone marrow. C-kit gene is a Receptor Tyrosine Kinase class III (RTK) that is expressed by early hematopoietic progenitor cells and plays an important role in hematopoietic stem cell proliferation, differentiation and survival. It is known that c-kit is a proto-oncogene and the activating c-kit mutations are likely to contribute in the development of leukaemia in humans. Exon 11 of c-Kit gene is the frequent site for mutations in different kinds of tumours. METHODS: In order to determine the frequency and prevalence of exon 11 mutations in 51 AML cases, we have done polymerase chain reaction-single-strand conformational polymorphism followed by direct DNA sequencing. RESULTS: The c-kit mutations in exon 11 were detected in 15.68% (8/51) in AML cases. We have detected totally ten missense mutations in eight AML cases those include Lys550Asn, Tyr568Ser, Ile571Leu, Tyr578Pro, Trp582Ser and Arg588Met and novel missense mutations at codons Ile563Lys and Val569Leu. Mutations at codons Ile571Leu and Trp582Ser was found in two independent cases. CONCLUSION: The presence of c-kit mutations in our study adds to investigative spectrum of AML cases. Since the c-kit mutations are seen in other malignancies, mutations in exon 11 of the c-kit gene might be involve in pathogenesis and represent useful predictive genetic marker in AML. Further studies in larger group of cases possibly will be required to determine the prognostic implications and to investigate how these mutations are co-related to the progression and pathogenesis of AML.