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1.
Front Oncol ; 14: 1365364, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38725622

RESUMO

Background: The progress in Colorectal cancer (CRC) screening and management has resulted in an unprecedented caseload for histopathological diagnosis. While artificial intelligence (AI) presents a potential solution, the predominant emphasis on slide-level aggregation performance without thorough verification of cancer in each location, impedes both explainability and transparency. Effectively addressing these challenges is crucial to ensuring the reliability and efficacy of AI in histology applications. Method: In this study, we created an innovative AI algorithm using transfer learning from a polyp segmentation model in endoscopy. The algorithm precisely localized CRC targets within 0.25 mm² grids from whole slide imaging (WSI). We assessed the CRC detection capabilities at this fine granularity and examined the influence of AI on the diagnostic behavior of pathologists. The evaluation utilized an extensive dataset comprising 858 consecutive patient cases with 1418 WSIs obtained from an external center. Results: Our results underscore a notable sensitivity of 90.25% and specificity of 96.60% at the grid level, accompanied by a commendable area under the curve (AUC) of 0.962. This translates to an impressive 99.39% sensitivity at the slide level, coupled with a negative likelihood ratio of <0.01, signifying the dependability of the AI system to preclude diagnostic considerations. The positive likelihood ratio of 26.54, surpassing 10 at the grid level, underscores the imperative for meticulous scrutiny of any AI-generated highlights. Consequently, all four participating pathologists demonstrated statistically significant diagnostic improvements with AI assistance. Conclusion: Our transfer learning approach has successfully yielded an algorithm that can be validated for CRC histological localizations in whole slide imaging. The outcome advocates for the integration of the AI system into histopathological diagnosis, serving either as a diagnostic exclusion application or a computer-aided detection (CADe) tool. This integration has the potential to alleviate the workload of pathologists and ultimately benefit patients.

2.
J Dermatolog Treat ; 33(5): 2571-2577, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35112978

RESUMO

BACKGROUND: Erroneous diagnoses of melanocytic lesions (benign, atypical, and malignant types) result in inappropriate surgical treatment plans. OBJECTIVE: To propose a deep learning (DL)-based fully automated diagnostic method using whole slide images (WSIs) for melanocytic lesions. METHODS: The method consisted of patch prediction using a DL model and patient diagnosis using an aggregation module. The method was developed with 745 WSIs and evaluated using internal and external testing sets comprising 182 WSIs and 54 WSIs, respectively. The results were compared with those of the classification by one junior and two senior pathologists. Furthermore, we compared the performance of the three pathologists in the classification of melanocytic lesions with and without the assistance of our method. RESULTS: The method achieved an accuracy of 0.963 and 0.930 on the internal and external testing sets, respectively, which was significantly higher than that of the junior pathologist (0.419 and 0.535). With assistance from the method, all three pathologists achieved higher accuracy on the internal and external testing sets; the accuracy of the junior pathologist increased by 39.0% and 30.2%, respectively (p < .05). CONCLUSION: This generalizable method can accurately classify melanocytic lesions and effectively improve the diagnostic accuracy of pathologists.


Assuntos
Aprendizado Profundo , Humanos , Patologistas
3.
Zhonghua Nan Ke Xue ; 27(9): 787-792, 2021 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-34914253

RESUMO

OBJECTIVE: To evaluate the safety and clinical efficiency of holmium laser enucleation of the prostate (HoLEP) in the treatment of small-volume BPH (SBPH) complicated by severe lower urinary tract symptoms (LUTS). METHODS: We retrospectively analyzed the clinical data on 82 cases of SBPH with severe LUTS treated by HoLEP from January 2017 to December 2018. The patients were aged (65.5 ± 7.6) years, with a mean prostate volume of <40 ml, a total IPSS of 24.8 ± 4.6, a QOL score of 5.2 ± 0.8, the maximum urinary flow rate (Qmax) of (7.6 ± 3.7) ml/s, and a mean PSA level of (1.8 ± 1.4) µg/L. RESULTS: All the operations were successfully completed, the mean operation time averaging (30.2 ± 5.0) min, enucleation time (26.7 ± 5.6) min and comminution time (3.5 ± 1.1) min, and the enucleated tissue weighing (20.3 ± 4.9) g. After surgery, the bladders were irrigated for (3.5 ± 1.9) h, with (3.0 ± 1.7) L of rinse solution, and catheterization lasted (24.8 ± 9.7) h. Histopathology revealed moderate or severe lymphocytic infiltration in 69 cases (84.1%). At 6 months after operation, significant improvement was observed in the IPSS, QOL, Qmax and PSA level compared with the baseline (P < 0.05). To date, no urethral stricture-related reoperation was ever necessitated. CONCLUSIONS: HoLEP is safe and effective for the treatment of SBPH complicated by severe LUTS and can be employed after adequate preoperative evaluation of the patient.《.


Assuntos
Lasers de Estado Sólido , Sintomas do Trato Urinário Inferior , Hiperplasia Prostática , Humanos , Sintomas do Trato Urinário Inferior/etiologia , Sintomas do Trato Urinário Inferior/cirurgia , Masculino , Próstata/cirurgia , Hiperplasia Prostática/complicações , Hiperplasia Prostática/cirurgia , Qualidade de Vida , Estudos Retrospectivos
4.
Am J Transl Res ; 13(5): 5035-5042, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34150089

RESUMO

OBJECTIVE: To evaluate the safety and effectiveness of ultrasonography-guided radiofrequency ablation combined with lauromacrogol foam sclerotherapy for the treatment of mixed thyroid nodules. METHODS: One hundred and nineteen patients with benign mixed thyroid nodules were included in this study. In all patients, radiofrequency ablation was performed on the solid components of nodules, and the cystic areas of nodules were treated with aspiration, irrigation with lauromacrogol injection and foam sclerotherapy. The nodule volume reduction ratio and thyroid-related laboratory tests were measured during operation and at 1, 3, 6, and 12 months after operation, and intraoperative and postoperative complications were recorded. RESULTS: A total of 136 mixed thyroid nodules from 119 patients all achieved complete ablation. At 1, 3, 6, and 12 months after treatment, the nodule volume decreased gradually while the volume reduction ratio increased gradually (P<0.05). The thyroid function of all patients returned to normal after operation, but 3 patients exhibited cyst recurrence. After the operation, no serious complications occurred. CONCLUSION: Ultrasonography-guided radiofrequency ablation combined with lauromacrogol sclerotherapy is a safe and effective method for the treatment of mixed thyroid nodules with less surgical trauma and low incidence of complications.

5.
Front Pediatr ; 9: 678296, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34095036

RESUMO

Purpose: This study aimed to figure out the association between ophthalmic and pathological features in patients with Linear Nevus Sebaceous Syndrome (LNSS) and in patients with Oculoectodermal Syndrome-Encephalocraniocutaneous Lipomatosis (OES-ECCL). Methods: It is a retrospective, non-consecutive, observational case series. Twenty-seven patients (12 with LNSS and 15 with OES-ECCL, 41 eyes) referred to the Department of Ophthalmology of the Shanghai Ninth People's Hospital between 2000 and 2020 were included. The mean age of the study population for the first-time consult was 5.7 years, ranging from 3 months to 34 years. Clinical notes, pathological records, and imaging findings were reviewed in all the patients. Results: Fourteen (51.9%) cases showed bilateral ocular involvement. Epibulbar choristomas were seen in all the patients. All the lesions involved the conjunctiva and cornea simultaneously. Multiple lesions were observed in 12 eyes. Of the 14 excised lesions, 11 were found to be complex choristomas. Further, 24 (89%) patients had eyelid coloboma. Also, 13 patients (48%) were diagnosed with strabismus, and 12 patients (44%) had abnormal fundus imaging, including optic nerve hypoplasia. Conclusions: LNSS and OES-ECCL shared common ophthalmic features, including epibulbar choristomas with distinctive characteristics, eyelid coloboma, strabismus, and optic nerve hypoplasia. The complex choristoma was found to be associated with the diseases. These specific patterns can be diagnostic clues to distinguish them from other syndromes, such as craniofacial defects, and to remind ophthalmologists that such patients require additional dermatological and neurological examinations and referral. Moreover, a thorough evaluation of ocular conditions is imperative for early interventions.

6.
Arch Dermatol Res ; 312(9): 665-673, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32157373

RESUMO

Melanoma, a malignancy of the melanocyte, is characterized as the most fatal skin cancer with an increasing incidence. Of note, in spite of great attempts made for better treatment, the therapeutic outcome is barely satisfactory. Abnormal expression of microRNAs (miRNAs) acting as oncogenes or tumor suppressor genes, is frequently implicated in multiple human cancers, including melanoma. Here, we found that miRNA-4458, a reportedly tumor-suppressive miRNA in several cancers, was downregulated in melanoma cells. Besides, our findings indicated that microRNA-4458 (miR-4458) hindered cell proliferation and migration, yet induced apoptosis in melanoma. Mechanical interaction of miR-4458 and PBX3 mRNA, thereby inhibiting PBX3 expression in melanoma cells, was also presented in this work. Human antigen R (HuR) was reported to be greatly upregulated in diverse cancers and HuR-dependent stabilization of target gene contributed a lot to tumor progression. In this study, it revealed the stabilization of PBX3 mRNA by HuR, thereby boosting PBX3 expression. Lastly, we concluded that miR-4458 and HuR modulated the expression of PBX3 in a competitive manner in melanoma tumorigenesis, which might yield a novel insight into the molecular pathogenesis of melanoma.


Assuntos
Proteína Semelhante a ELAV 1/metabolismo , Proteínas de Homeodomínio/genética , Melanoma/genética , MicroRNAs/metabolismo , Proteínas Proto-Oncogênicas/genética , Neoplasias Cutâneas/genética , Carcinogênese/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Melanoma/patologia , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Neoplasias Cutâneas/patologia
7.
Immunopharmacol Immunotoxicol ; 40(1): 91-97, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29303012

RESUMO

PURPOSE: Myeloid derived suppressor cells (MDSC) play an important role in tumor immune evasion and its level significantly increased in patients with gastric cancer. Studies confirmed the associations between MDSC and various cytokines in the peripheral blood. However, little is known about the mechanism drawing MDSC into tumor parenchyma. This study was to analyze the correlation between MDSC subsets and CCR5 level in gastric cancer. MATERIALS AND METHODS: G-MDSC and M-MDSC from the peripheral blood and tumor parenchyma were analyzed by flow cytometry. CCR5 ligand CCL5 was detected by ELISA. CCR5 was detected by real-time PCR, western blot and flow cytometry. Furthermore, the therapeutic effects of CCR5 blockade was assessed by the tumor model. RESULTS: CCR5 ligand, gene and protein expression of CCR5, and surface expression of CCR5 significantly increased in blood and tumor of tumor-bearing mice, suggesting MDSC may be attracted into the parenchyma by CCL5/CCR5. Anti-CCR5 treatment decreased G-MDSC and M-MDSC in the periphery and tumor. In addition, combination treatment enhanced CD4+ and CD8+ T cell infiltration and decreased the tumor burden of tumor-bearing mice. CONCLUSIONS: This study elucidated a possible association between MDSC subsets and CCR5, in addition to provide a new potential target to enhance the efficacy of immunotherapy in patients with gastric cancer.


Assuntos
Anticorpos Antineoplásicos/farmacologia , Imunidade Celular/efeitos dos fármacos , Células Supressoras Mieloides/imunologia , Proteínas de Neoplasias , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptores CCR5/imunologia , Neoplasias Gástricas , Animais , Linhagem Celular Tumoral , Quimiocina CCL5/imunologia , Feminino , Camundongos , Células Supressoras Mieloides/patologia , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/imunologia , Receptor de Morte Celular Programada 1/imunologia , Neoplasias Gástricas/tratamento farmacológico , Neoplasias Gástricas/imunologia , Neoplasias Gástricas/patologia
8.
Int J Clin Exp Pathol ; 11(6): 3191-3198, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-31938449

RESUMO

Angiosarcoma is a malignant tumor of endothelial origin. Epithelioid angiosarcoma is a subtype of angiosarcoma, in which the malignant endothelial cells have a predominantly epithelioid appearance. So far, few cases of primary hepatic epithelioid andiosarcoma (PHEA) have been described. In this case report, we describe two rare cases of PHEA. Microscopically, the tumors were consistently composed of atypical epithelioid cells with vesicular nuclei, prominent nucleoli, and eosinophilic cytoplasm. One patient had metastatic disease and underwent palliative hepatic surgery following radiotherapy and chemotherapy, and had a postoperative survival time of 12 months, while the other patient is still alive after tumor resection. PHEA is an aggressive malignant tumor with a high rate of metastasis.

9.
Oncol Rep ; 38(4): 2148-2154, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28791406

RESUMO

Hepatocellular carcinoma (HCC) is the most common type of primary liver cancer in adults and effective therapy for human liver cancer remains a difficult clinical concern. Researchers have demonstrated that microRNAs play important roles in the tumorigenesis and tumor progression of human liver cancer; therefore, regulation of microRNAs may be a new strategy for HCC therapy. MicroRNA-196a (miR-196a) has been reported to be overexpressed in many types of cancers. However, the regulatory effects of miR-196a in human liver cancer are not fully understood. In the present study, we found that miR-196a was overexpressed in human liver cancer cells compared to that observed in normal liver cells. MTT and colony formation assays indicated that downregulation of miR-196a inhibited liver cancer cell proliferation which was due to the induction of cell apoptosis. A mouse model demonstrated that downregulation of miR-196a also inhibited human liver cancer cell migration and invasion in vivo. Further study indicated that FOXO1 is a direct target of miR-196a, and inhibition of FOXO1 promoted human liver cancer cell growth. Taken together, the present study demonstrated that the expression of miR-196a in human liver cancer cells was upregulated; downregulation of miR-196a regulated human liver cancer cell biological functions which could benefit the clinical therapy of human liver cancer in the future.


Assuntos
Carcinoma Hepatocelular/genética , Proteína Forkhead Box O1/genética , Neoplasias Hepáticas/genética , MicroRNAs/genética , Animais , Apoptose/genética , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Proliferação de Células/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Invasividade Neoplásica/genética , Ensaios Antitumorais Modelo de Xenoenxerto
10.
J Am Acad Dermatol ; 74(3): 527-35, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26892654

RESUMO

BACKGROUND: After pulsed dye laser (PDL) treatment, facial lateral port-wine stains (PWS) clear quicker and more completely than central PWS do. OBJECTIVE: We sought to investigate whether the difference in the efficacy of the treatment between central and lateral facial PWS was related to different histologic manifestations. METHOD: Thirteen patients with PWS had biopsies and underwent PDL treatments in both central and lateral areas of the face. The hypothesis was tested by correlating the PWS response to PDL with the depth and diameter of the PWS vessels. The clinical efficacy was assessed by chromameter 2 months after the final PDL treatment, whereas diameter and depth of PWS vessels were measured in biopsy specimens. RESULTS: All patients were treated on central and lateral facial sites. The chromameter evaluation showed that the average blanching rate was 34.01% and 8.68% for lateral and central facial sites, respectively (P < .05), which suggests a better response to PDL treatment in the lateral than in the central area. Histologic manifestations showed that vessels in the lateral regions were primarily located in the papillary dermis, whereas in the central regions they were extensively distributed from the dermis into the subcutaneous tissue. LIMITATIONS: The small number of cases included in this study and the lack of follow-up longer than 2 months constitute limitations. CONCLUSION: Lateral facial PWS respond better to PDL than PWS located in the central face. Differences in vessel location and diameter may be responsible for the variations in PWS response to PDL.


Assuntos
Face/patologia , Lasers de Corante/uso terapêutico , Mancha Vinho do Porto/patologia , Mancha Vinho do Porto/cirurgia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
11.
Photodiagnosis Photodyn Ther ; 12(1): 143-5, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25461965

RESUMO

Port-wine stain (PWS) is still a challenging condition for clinician to treat, because in the majority of cases, the stains are not lifted fully by treatment with laser therapy. Photodynamic therapy (PDT) was considered recently as a promising alternative treatment for PWS. We report here long-term follow-up measures 18 years on PWS lesion treated with PDT and the histological data of residual PWS.


Assuntos
Dermatoses Faciais/tratamento farmacológico , Dermatoses Faciais/patologia , Fotoquimioterapia/métodos , Mancha Vinho do Porto/tratamento farmacológico , Mancha Vinho do Porto/patologia , Adolescente , Feminino , Humanos , Estudos Longitudinais , Fármacos Fotossensibilizantes/uso terapêutico , Resultado do Tratamento
12.
Cancer Res ; 74(24): 7546-59, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25320014

RESUMO

Cancer stem-like cells (CSC) thought to contribute to head and neck squamous carcinomas (HNSCC) may offer attractive therapeutic targets if a tractable approach can be developed. In this study, we report that silencing c-Met is sufficient to suppress sphere formation, tumor initiation, and metastatic properties of HN-CSC. Pharmacologic inhibition of c-Met with the selective inhibitor PF-2341066 preferentially targeted CSC and synergized with conventional chemotherapy to improve efficacy in a mouse xenograft model of HNSCC, impeding tumor growth and reducing metastasis. Mechanistic investigations showed that CSC elimination was due to downregulation of Wnt/ß-catenin signaling in HN-CSC and that the Wnt pathway receptor FZD8 was essential for interactions of c-Met and Wnt/ß-catenin signaling in HN-CSC. Notably, ectopic expression of FZD8 rescued the impaired phenotype of HN-CSC where c-Met was inhibited. Furthermore, c-Met upregulated FZD8 through the ERK/c-Fos cascade in HN-CSC. Taken together, our results offer a preclinical proof-of-concept for targeting the c-Met/FZD8 signaling axis as a CSC-directed therapy to improve HNSCC treatment.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Células-Tronco Neoplásicas/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/genética , Receptores de Superfície Celular/genética , Animais , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Crizotinibe , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Camundongos , Piperidinas/administração & dosagem , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Pirazóis , Piridinas/administração & dosagem , Receptores de Superfície Celular/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
13.
World J Gastroenterol ; 16(30): 3847-52, 2010 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-20698049

RESUMO

AIM: To study the germline mutation of hPMS2 gene in 26 unrelated Chinese hereditary nonpolyposis colorectal cancer (HNPCC) probands and to fulfill the screening strategy for HNPCC in Chinese. METHODS: Genomic DNA was extracted from the peripheral blood. To avoid the interference of pseudogene in detection of the remaining 11 exons (exon 1-5, 9, 11-15), long-range polymerase chain reaction (PCR) was conducted to amplify the complete coding region of hPMS2 gene firstly. Then 1/8 of the PCR products were used as template to amplify the individual exon respectively and DNA sequencing was done. Direct DNA sequencing of the conventional PCR products of exon 6, 7, 8 and 10 of hPMS2 gene was performed. The same analysis was made in 130 healthy persons without family histories of HNPCC to further investigate the pathological effects of the detected missense mutation. RESULTS: One HNPCC proband fulfilled Bethesda guidelines and was found to carry the germline mutation of hPMS2 gene, which has not been reported in Chinese HNPCC families. It was a missense mutation at c.1532C>T of exon 11. It was detected in three controls as well with an occurrence rate of 2.3% (3/130). Since it could not be found in the PMS2-single nucleotide polymorphism (SNP) database, this missense mutation is a new SNP unreported up to date. Meanwhile, 260 reported SNPs of hPMS2 gene were detected in the 26 HNPCC probands. The 2nd and 5th exons were probably the hot SNP regions of hPMS2 gene in Chinese HNPCC families involving 53.1% of all reported SNP. CONCLUSION: The germline mutation of hPMS2 gene may be rare in Chinese HNPCC families. The 2nd and 5th exons are hot SNP regions of hPMS2 gene.


Assuntos
Adenosina Trifosfatases/genética , Povo Asiático/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Enzimas Reparadoras do DNA/genética , Proteínas de Ligação a DNA/genética , Mutação em Linhagem Germinativa , Mutação de Sentido Incorreto , Polimorfismo de Nucleotídeo Único , Sequência de Bases , Estudos de Casos e Controles , China/epidemiologia , Neoplasias Colorretais Hereditárias sem Polipose/etnologia , Análise Mutacional de DNA , Éxons , Predisposição Genética para Doença , Hereditariedade , Humanos , Endonuclease PMS2 de Reparo de Erro de Pareamento , Dados de Sequência Molecular , Linhagem , Fenótipo , Reação em Cadeia da Polimerase
14.
World J Gastroenterol ; 14(48): 7329-34, 2008 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-19109866

RESUMO

AIM: To detect the MLH1 gene promoter germline-methylation in probands of Chinese hereditary nonpolyposis colorectal cancer (HNPCC), and to evaluate the role of methylation in MLH1 gene promoter and molecular genetics in screening for HNPCC. METHODS: The promoter germline methylation of MLH1 gene was detected by methylation-specific PCR (MSP) in 18 probands from unrelated HNPCC families with high microsatellite-instability (MSI-H) phenotype but without germline mutations in MSH2, MLH1 and MSH6 genes. At the same time, 6 kindreds were collected with microsatellite-stability (MSS) phenotype but without germline mutations in MSH2, MLH1 and MSH6 genes as controls. The results of MSP were confirmed by clone sequencing. To ensure the reliability of the results, family H65 with nonsense germline mutation at c.2228C > A in MSH2 gene was used as the negative control and the cell line sw48 was used as the known positive control along with water as the blank control. Immunochemical staining of MLH1 protein was performed with Envision two-step method in those patients with aberrant methylation to judge whether the status of MLH1 gene methylation affects the expression of MLH1 protein. RESULTS: Five probands with MLH1 gene promoter methylation were detected in 18 Chinese HNPCC families with MSI-H phenotype but without germline mutations in MSH2, MLH1 and MSH6 genes. Two of the five probands from families H10 and H29 displayed exhaustive-methylation, fulfilling the Japanese criteria (JC) and the Amsterdam criteria (AC), respectively. The other 3 probands presented part-methylation fulfilling the AC. Of the 13 probands with unmethylation phenotype, 8 fulfilled the JC and the Bethesda guidelines (BG), 5 fulfilled the AC. The rate of aberrant methylation in MLH1 gene in the AC group (22.2%, 4/18) was higher than that in the JC/BG groups (5.6%, 1/18) in all HNPCC families with MSI-H phenotype but without germline mutations in MSH2, MLH1 and MSH6 genes. However, no proband with methylation in MLH1 gene was found in the families with MSS phenotype and without germline mutations in MSH2, MLH1 and MSH6 genes. No expression of MLH1 protein was found in tumor tissues from two patients with exhaustive-methylation phenotype, whereas positive expression of MLH1 protein was observed in tumor tissues from patients with partial methylation phenotype (excluding family H42 without tumor tissue), indicating that exhaustive-methylation of MLH1 gene can cause defective expression of MLH1 protein. CONCLUSION: Methylation phenotype of MLH1 gene is correlated with microsatellite phenotype of MMR genes, especially with MSI-H. Exhaustive-methylation of MLH1 gene can silence the expression of MLH1 protein. MLH1 promoter methylation analysis is a promising tool for molecular genetics screening for HNPCC.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Neoplasias Colorretais Hereditárias sem Polipose/etnologia , Neoplasias Colorretais Hereditárias sem Polipose/genética , Metilação de DNA/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas/genética , Adulto , Idoso , Estudos de Casos e Controles , China , Proteínas de Ligação a DNA/genética , Feminino , Testes Genéticos , Mutação em Linhagem Germinativa/genética , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Proteína 1 Homóloga a MutL , Proteína 2 Homóloga a MutS/genética , Fenótipo
15.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 24(6): 640-5, 2007 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-18067074

RESUMO

OBJECTIVE: To detect the germline mutation of mismatch repair gene (MSH6) in hereditary nonpolyposis colorectal cancer (HNPCC) kindreds fulfilling different clinical criteria. METHODS: The germline mutations of MSH6 gene were detected by PCR based DNA sequencing in 39 unrelated HNPCC probands fulfilling different clinical criteria in which MSH2 and MLH1 mutations were excluded. The exons with missense mutations were analyzed using PCR sequencing in the germline genomic DNA of 137 healthy persons. The expression of MSH6 protein was detected by Envision immunohistochemistry staining in the tumor tissues of the mutational probands. RESULTS: Six germline mutations of MSH6 gene were detected in 39 probands of Chinese HNPCC kindreds, and the mutations distributed in the exon 4, 6, 9 and 10. Four out of six mutations were missense mutation, one was nonsense mutation and the remaining one was insertion mutation in splice site. The results of sequecing for the exons with above four missense mutations in 137 healthy persons' genomic DNA showed that 5 of 137 persons had the missense mutation of c.3488 A to T at codon 1163 of the 6th exon. The mutational rate was approximately 3.65% (5/137), so the mutation could be a single nucleotide polymorphism (SNP). The remaining missense mutations were not found in any germline genomic DNA of 137 healthy persons. Positive expression of MSH6 protein had been identified in the tumor of the SNP proband while the tumors had negative MSH6 protein expression in the rest probands of germline mutation MSH6 gene. The types of mutations and their potential significance were determined by comparing the following databases: http://www.ncbi.nlm.nih.gov/, http://www.ensembl.org/homo-sapies, and http://www.insight-group.org. Five out of the six mutations had not been reported previously and they were new pathological mutations, the rest one was a new SNP. CONCLUSION: Germline mutations of MSH6 gene may play an important role in Chinese HNPCC kindreds fulfilling different clinical criteria. It is necessary to analyze the germline mutations of MSH6 gene using sequencing to identify HNPCC families in the probands in which MSH2 and MLH1 mutation were excluded.


Assuntos
Pareamento Incorreto de Bases/genética , Neoplasias Colorretais Hereditárias sem Polipose/genética , Enzimas Reparadoras do DNA/genética , Mutação em Linhagem Germinativa/genética , Proteína MutS de Ligação de DNA com Erro de Pareamento/genética , Adulto , Povo Asiático/genética , Neoplasias Colorretais Hereditárias sem Polipose/patologia , Análise Mutacional de DNA , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Proteína 2 Homóloga a MutS/genética , Linhagem , Reação em Cadeia da Polimerase
16.
World J Gastroenterol ; 13(37): 5021-4, 2007 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-17854147

RESUMO

AIM: To investigate the germline mutations of MSH6 gene in probands of Chinese hereditary non-polyposis colorectal cancer (HNPCC) families fulfilling different clinical criteria. METHODS: Germline mutations of MSH6 gene were detected by PCR-based DNA sequencing in 39 unrelated HNPCC probands fulfilling different clinical criteria in which MSH2 and MLH1 mutations were excluded. To further investigate the pathological effects of detected missense mutations, we analyzed the above related MSH6 exons using PCR-based sequencing in 137 healthy persons with no family history. The clinicopathological features were collected from the Archive Library of Cancer Hospital, Fudan University and analyzed. RESULTS: Four germline missense mutations distributed in the 4(th), 6(th) and 9(th) exons were observed. Of them, three were not found in international HNPCC databases and did not occur in 137 healthy controls, indicating that they were novel missense mutations. The remaining mutation which is consistent with the case H14 at c.3488A>T of exon 6 of MSH6 gene was also found in the controls, the rate was approximately 3.65% (5/137) and the type of mutation was not found in the international HNPCC mutational and SNP databases, suggesting that this missense mutation was a new SNP unreported up to date. CONCLUSION: Three novel missense mutations and a new SNP observed in the probands of Chinese HNPCC families, may play an important role in the development of HNPCC.


Assuntos
Neoplasias Colorretais/genética , Proteínas de Ligação a DNA/genética , Éxons/genética , Mutação em Linhagem Germinativa/genética , Mutação de Sentido Incorreto/genética , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , China , Neoplasias Colorretais/etnologia , Feminino , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
17.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 21(1): 64-7, 2004 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-14767913

RESUMO

OBJECTIVE: To investigate the relationship between the single nucleotide polymorphisms(SNPs) in the redox domain of aprimidinic/apurinic endonuclease/redox factor-1(APEX) gene and the development of sporadic colorectal cancer. METHODS: One hundred and fifty cases of sporadic colorectal cancers and 143 peripheral blood samples from healthy population were screened for genetic polymorphisms or mutations in the redox domain by denaturing gradient gel electrophoresis followed by DNA sequencing. RESULTS: There were two SNPs identified in the redox domain of APEX gene, namely, 453G to T and 1247A to G. The gene frequencies of 453T and 1247G were 1.3% and 5.7%, respectively, in patient group, while 1.05% and 4.55%, respectively, in healthy population. The genotype distribution at the two sites in healthy population was consistent with Hardy-Weinberg equilibrium. There was no difference in gene frequencies at the two sites between cancer patients and healthy population. CONCLUSION: The polymorphisms in the redox domain of APEX gene are irrelevant to the development of sporadic colorectal cancer, but their distribution may vary greatly among tribes.


Assuntos
Neoplasias Colorretais/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Polimorfismo de Nucleotídeo Único , Idoso , Alelos , Sequência de Bases , Sítios de Ligação/genética , China , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Análise Mutacional de DNA , DNA de Neoplasias/química , DNA de Neoplasias/genética , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Oxirredução , Mutação Puntual
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