Roles of long non-coding RNAs in digestive tract cancer and their clinical application / 浙江大学学报·医学版

Long non-coding RNAs (lncRNAs) are strongly related to the occurrence and development of digestive tract cancer in human. Firstly, lncRNAs target and regulate the expression of downstream cancer genes to affect the growth, metastasis, apoptosis, metabolism and immune escape of cancer cells. Secondly, lncRNAs are considered to be important regulating factors for lipid metabolism in cancer, which is related to signaling pathways of adipogenesis and involved in the occurrence and development of digestive tract cancer. Finally, lncRNAs have application value in the diagnosis and treatment of digestive tract cancer. For example, lncRNAMALAT1 has been reported as a target for diagnosis and treatment of hepatocellular carcinoma. This article reviews current progress on the regulatory role of lncRNAs in digestive tract cancer, to provide references for the research and clinical application in the prevention and treatment of digestive tract cancer.

La "cultura de la sobrevivencia" y la salud pública internacional en América Latina: la Guerra Fría y la erradicación de enfermedades a mediados del siglo XX / The "culture of survival" and international public health in Latin America: the Cold War and the eradication of diseases in the mid-twentieth century

Este artículo analiza las principales campañas promovidas por agencias internacionales y organismos nacionales de salud dirigidas a erradicar enfermedad infecciosas en el ámbito rural latinoamericano de los años 1940 y 1950. Las dimensiones políticas del periodo han sido estudiadas pero todavía se ha prestado poca atención a sus dimensiones sanitarias. Este trabajo propone el concepto de "cultura de la sobrevivencia" para explicar los problemas de la salud pública oficial de Estados con políticas sociales limitadas que no permitieron el ejercicio de la ciudadanía. La salud pública, como parte de esta cultura de la sobrevivencia, buscaba ser una solución temporal sin enfrentarse a los problemas sociales que originaban las infecciones y dejó un legado en la salud pública de la región.

This article analyzes the main campaigns run by international agencies and national health bodies to eradicate infectious diseases in rural Latin America in the 1940s and 1950s. The political dimensions of the period have been studied but there has been little attention as yet to the health dimensions. This article proposes the concept of a "culture of survival" to explain the official public health problems of states with limited social policies that did not allow the exercise of citizenship. Public health, as part of this culture of survival, sought a temporary solution without confronting the social problems that led to infections and left a public health legacy in the region.

Role of Long Non-coding Ribonucleic Acid in Gastrointestinal Cancer / 대한소화기학회지

With the improvement of high-throughput genomic technology such as microarray and next-generation sequencing over the last ten to twenty year, we have come to know that the portion of the genome responsible for protein coding constitutes just approximately 1.5%. The remaining 98.5% of the genome not responsible for protein coding have been regarded as 'junk DNA'. More recently, however, 'Encyclopedia of DNA elements project' revealed that most of the junk DNA were transcribed to RNA regardless of being translated into proteins. In addition, many reports support that a lot of these non-coding RNAs play a role in gene regulation. In fact, there are various functioning short non-coding RNAs including rRNA, tRNA, small interfering RNA, and micro RNA. Mechanisms of these RNAs are relatively well-known. Until recently, however, little is known about long non-coding RNAs which consist of 200 nucleotides or more. In this article, we will review the representative long non-coding RNAs which have been reported to be related to gastrointestinal cancers and to play a certain role in its pathogenesis.

Role of Long Non-coding Ribonucleic Acid in Gastrointestinal Cancer / 대한소화기학회지

With the improvement of high-throughput genomic technology such as microarray and next-generation sequencing over the last ten to twenty year, we have come to know that the portion of the genome responsible for protein coding constitutes just approximately 1.5%. The remaining 98.5% of the genome not responsible for protein coding have been regarded as 'junk DNA'. More recently, however, 'Encyclopedia of DNA elements project' revealed that most of the junk DNA were transcribed to RNA regardless of being translated into proteins. In addition, many reports support that a lot of these non-coding RNAs play a role in gene regulation. In fact, there are various functioning short non-coding RNAs including rRNA, tRNA, small interfering RNA, and micro RNA. Mechanisms of these RNAs are relatively well-known. Until recently, however, little is known about long non-coding RNAs which consist of 200 nucleotides or more. In this article, we will review the representative long non-coding RNAs which have been reported to be related to gastrointestinal cancers and to play a certain role in its pathogenesis.

A Novel Germline Mutation in Exon 10 of the SMAD4 Gene in a Familial Juvenile Polyposis

Familial juvenile polyposis (FJP) is a rare autosomal dominant hereditary disorder that is characterized by the development of multiple distinct juvenile polyps in the gastrointestinal tract and an increased risk of cancer. Recently, germline mutations, including mutations in the SMAD4, BMPR1A, PTEN and, possibly, ENG genes, have been found in patients with juvenile polyps. We herein report a family with juvenile polyposis syndrome (JPS) with a novel germline mutation in the SMAD4 gene. A 21-year-old man presented with rectal bleeding and was found to have multiple polyps in his stomach, small bowel, and colon. His mother had a history of gastrectomy for multiple gastric polyps with anemia and a history of colectomy for colon cancer. A review of the histology of the polyps revealed juvenile polyps in both patients. Subsequently, mutation screening in DNA samples from the patients revealed a germline mutation in the SMAD4 gene. The pair had a novel mutation in exon 10 (stop codon at tyrosine 413). To our knowledge, this mutation has not been previously described. Careful family history collection and genetic screening in JPS patients are needed to identify FJP, and regular surveillance is recommended.

Genetic studies in a coexistence of acromegaly, pheochromocytoma, gastrointestinal stromal tumor (GIST) and thyroid follicular adenoma / Estudos genéticos na coexistência de acromegalia, feocromocitoma, tumor do estroma gastrointestinal (GIST) e adenoma folicular de tireoide

We report on an adult woman with rare coexistence of acromegaly, pheochromocytoma (PHEO), gastrointestinal stromal tumor (GIST), intestinal polyposis, and thyroid follicular adenoma. At the age of 56, she was diagnosed with acromegaly caused by a pituitary macroadenoma, treated by transsphenoidal surgery, radiotherapy, and octreotide. During routine colonoscopy, multiple polyps were identified as tubular adenomas with high-grade dysplasia on histology. Years later, an abdominal mass of 8.0 x 6.2 cm was detected by routine ultrasound. Surgical exploration revealed an adrenal mass and another tumor adhered to the lesser gastric curvature, which were removed. Pathology confirmed the diagnosis of PHEO and GIST. PHEO immunohistochemistry was negative for GHRH. During follow-up, nodular goiter was found with normal levels of calcitonin and inconclusive cytology. Near-total thyroidectomy was performed, revealing a follicular adenoma. Her family history was negative for all of these tumor types. Genetic analysis for PHEO/paraganglioma genes (SDH A-D, SDHAF2, RET, VHL, TMEM127, and MAX), and pituitary-related genes (AIP, MEN1, and p27) were negative. Though the finding of PHEO and acromegaly with multiple other tumors could be a fortuitous coexistence, we suggest that this case may represent a new variant of MEN syndrome with a de novo germline mutation in a not yet identified gene. Arq Bras Endocrinol Metab. 2012;56(8):507-12.

Relatamos o caso de uma mulher com rara coexistência de acromegalia, feocromocitoma (FEO), tumor do estroma gastrointestinal (GIST), polipose intestinal e adenoma folicular de tireoide. Aos 56 anos, ela foi diagnosticada com acromegalia por um macroadenoma hipofisário, tratado com cirurgia transesfenoidal, radioterapia e octreotide. Uma colonoscopia de rotina detectou múltiplos pólipos, que à histologia eram adenomas tubulares com alto grau de displasia. Anos mais tarde, uma ecografia detectou uma massa abdominal de 8.0 x 6.2 cm, que na exploração cirúrgica era uma lesão adrenal e outro tumor aderido à pequena curvatura gástrica. A patologia confirmou os diagnósticos de FEO e GIST. A imuno-histoquímica do FEO foi negativa para GHRH. No seguimento, encontrou-se um bócio nodular com níveis normais de calcitonina e citologia inconclusiva. Após tireoidectomia total o diagnóstico histológico foi de adenoma folicular. A história familiar era negativa para todos esses tumores. As análises genéticas para genes de síndromes de FEO/paragangliomas (SDH A-D, SDHAF2, RET, VHL, TMEM127 e MAX) e para hipofisárias (AIP, MEN1 e p27) foram todas negativas. Embora a presença de FEO e acromegalia com múltiplos outros tumores possa ser uma coexistência fortuita, acreditamos na possibilidade de uma nova variante de NEM com uma mutação germinativa de novo em um gene ainda não identificado Arq Bras Endocrinol Metab. 2012;56(8):507-12.

Características genético-moleculares de los tumores estromales gastrointestinales (GIST) / Molecular and genetic features of gastrointestinal stromal tumors (GIST)

Los tumores estromales gastrointestinales (GIST) son neoplasias mesenquimales que típicamente surgen a nivel del estómago, intestino delgado, colon, y otros sitios en la cavidad abdominal y su identificación se ha incrementado por mejoras en los criterios de detección. La mayor parte de los tumores GIST son causados por mutaciones activadoras en los genes de receptores transmembranares tirosina quinasa c-KIT y receptor alpha del factor de crecimiento derivado de plaquetas (PDGFRA). Las mutaciones causales de GIST se restringen solo a ciertas regiones del gen que corresponden a importantes zonas funcionales de c-KIT o PDGFRA. Se reporta que hasta 70% de casos de GIST se debe a mutaciones en el exón 11 del gen c-Kit que corresponde a la región yuxtamembrana del receptor. La región y el tipo de mutación determinan diferencialmente cómo se desarrolla la neoplasia, el pronóstico y su respuesta a inhibidores de las tirosina quinasas como el Imanatib. Por tal motivo, el genotipado de KIT y PDGFRA es importante para el diagnóstico y establecimiento de la sensibilidad a los inhibidores tirosina quinasa.

Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms typically arising in the stomach, small intestine, colon, and other sites in the abdominal cavity and its identification has improved dramatically mainly due to better criteria in its detection. Most GISTs tumors harbor activating mutations in the tyrosine kinase receptor c-KIT or platelet derived growth factor receptor-alpha (PDGFRA). Those mutations are restricted to a few regions corresponding to important functional domains of c-KIT or PDGFRA. Upto 70% of cases are due to mutations in exon 11 of c-KIT corresponding to its juxtamembrane region of the receptor. The location and type of mutation will differentially determine the development of the disease, its prognosis and the response to inhibitors of tyrosine kinases as Imanatib. For this reason, genotyping c-KIT and PDGFRA is important for GIST diagnosis and assessment of sensitivity to tyrosine kinase inhibitors.

A primary study of criterion for source identification of gastrointestinal tumor sample with Identifiler multiplex system / 法医学杂志

OBJECTIVE@#To investigate the criterion for source identification of gastrointestinal tumor based on the number of identical allele (IAn) and the number of matched STR locus with 2 identical alleles (A2) in Identifiler system.@*METHODS@#One hundred and five pairs of gastrointestinal tumor samples and homologous normal samples (TN group) were genotyped with Identifiler system. The numbers of STR locus with genotypic alteration (STRGA) in each tumor were determined by comparing the genotype of the matched STR loci in each pair of samples. According to the limited distribution of IAn and A2, 16 different values of IAn was substituted into the published discriminant functions to obtain the cut-off values of IAn and A2 for source identification of tumor sample. Indices including sensitivity (SEN), specificity (SPE), accuracy (AC), positive predictive value (PPV) and negative predictive value (NPV) for distinguishing tumor from an unrelated individual or a full sibling of the patient were calculated. Concordance of the identification results based on the determined criteria and the definite facts were statistically tested with Kappa index.@*RESULTS@#The total frequency of STRGA was 5.46%. There were 31.43% of the 105 tumor samples carried at least one STR locus with STRGA mutation. According to the Fisher discrimination rules, criteria I (IAn>or=23 and A2>or=8) and criteriall (IAn>or=26 and A2>or=11) meet the requirements of distinguishing tumor sample from an unrelated individual or a full sibling of the patient with tumor, respectively. SEN=0.971 0, PPV=1.000 0, PPV=0.891 9 and Kappa=0.923 5, when the criteria were used to determine the specified relatives.@*CONCLUSION@#Criteria I and criteria II were powerful for distinguishing tumor sample from an unrelated individual or a full sibling of the patient with tumor, respectively, when the Identifiler system was adopted for source identification of gastrointestinal tumor sample.

Estudio de patrones de metilación génica en tumores del tubo digestivo / Gene methylation patterns in digestive tumors

Background: The loss of tumor suppresor gene function damages the defensive mechanisms that protect the indemnity of genetic material. Promoter gene methylation is one of the inactivation mechanisms of suppressor genes. Aim: To study the methylation pattern of a group of genes in biopsy samples of gastrointestinal tumors. Material and methods: Forty eight gastric, 25 gallbladder, 24 colon and 6 pancreas cancer biopsy samples were randomly selected. The methylation pattern of CDH1, FHIT, CDKN2A, APC and MLH1 genes, was studied using a specific polymerase chain reaction test for methylation. Demographic, morphological and follow up variables of patients bearing the tumors were also analyzed. Results: The general methylation frequency of CDH1, FHIT, CDKN2A, APC and MLH1 genes was 64.1, 56, 39.8, 18.1 and 34 percent respectively. In gastric cancer samples there was a correlation between APC gene methylation and well differentiated tumors; between CDH1 methylation and Lauren diffuse type and the presence of three or more metastasic lymph nodes; between FHIT, CDKN2A and CDH1 gene methylation and male gender. In ¡ess differentiated gallbladder tumors, the frequency of CDH1 methylation was higher. There was a tendency towards a lower survival in colon and gastric cancer when MLH1 (p =0.07) y CDKN2A (p= 0.06) were methylated, respectively. Conclusions: An abnormal methylation pattern was associated with morphological features in gastric and gallbladder cancer and with a tendency towards a lower survival in colon and gastric cancer.

Evaluation of allelic alterations in 13 CODIS STR loci in tumor tissues from human digestive system / 法医学杂志

OBJECTIVE@#To study genetic alterations in 13 CODIS STR loci in various tumor tissue samples from human digestive system.@*METHODS@#Malignant tumor tissues and blood samples taken from 55 different unrelated individuals were collected. DNA samples were extracted using Chelex100 extraction kit, amplified using Profiler and Cofiler PCR amplification kit and analyzed using API 310 analyzer.@*RESULTS@#Aberrant cell divisions were detected in all of the 55 tumor tissue samples, with STR alternations detected in two samples including allelic alteration, partial and complete loss or unbalance of heterozygosity. Moreover, the alternations might occur simultaneously at more than one loci.@*CONCLUSION@#Caution must be taken in STR analysis of tumor tissue samples since the exclusion loci in forensic identification or paternity testing may be resulted from mutations in the tumor tissue.

Roles and causes of abnormal DNA methylation in gastrointestinal cancers.

Evidence now suggests that epigenetic abnormalities, particularly altered DNA methylation, play a crucial role in the development and progression of human gastrointestinal malignancies. Two distinct DNA methylation abnormalities are observed together in cancer. One is an overall genome-wide reduction in DNA methylation (global hypomethylation) and the other is regional hypermethylation within the CpG islands of specific gene promoters. Global hypomethylation is believed to induce proto-oncogene activation and chromosomal instability, whereas regional hypermethylation is strongly associated with transcriptional silencing of tumor suppressor genes. To date, genes involved in regulation of the cell cycle, DNA repair, growth signaling, angiogenesis, and apoptosis, are all known to be inactivated by hypermethylation. Recently developed techniques for detecting changes in DNA methylation have dramatically enhanced our understanding of the patterns of methylation that occur as cancers progress. One of the key contributors to aberrant methylation is aging, but other patterns of methylation are cancer-specific and detected only in a subset of tumors exhibiting the CpG island methylator phenotype (CIMP). Although the cause of altered patterns of DNA methylation in cancer remains unknown, it is believed that epidemiological factors, notably dietary folate intake, might strongly influence DNA methylation patterns. Recent studies further suggest that polymorphisms of genes involved in folate metabolism are causally related to the development of cancer. Identifying epidemiological factors responsible for epigenetic changes should provide clues for cancer prevention in the future.

Gen supresor de tumores p53 en neoplasias digestivas / p53 tumor supresor gene in digestive cancer

Malignant diseases of the digestive tract cause more than 50 percent of deaths due to cancer in Chile. There is a high incidence of gastric and gallbladder cancer and an increasing frequency of colorectal cancer. P53 tumor suppressor gene has a great importance in carcinogenesis and its alterations are specially important in digestive tract tumors such as colorectal cancer. There is contradictory evidence about the frequency of p53 gene or protein alterations or their biological significance. There is little information about p53 in Chile and it is mostly limited to immunohistochemical studies. This revision analyzes the frequency of p53 alterations in digestive tract tumors in Chile, using immunohistochemical and molecular biology methods. A special emphasis is given to the prognostic importance of this gene