• Title/Summary/Keyword: Genetic Heterogeneity

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Turning Hepatic Cancer Stem Cells Inside Out - A Deeper Understanding through Multiple Perspectives

  • Chan, Lok-Hei;Luk, Steve T.;Ma, Stephanie
    • Molecules and Cells
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    • v.38 no.3
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    • pp.202-209
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    • 2015
  • Hepatocellular carcinoma (HCC), a highly malignant disease and the third leading cause of all cancer mortalities worldwide, often responses poorly to current treatments and results in dismal outcomes due to frequent chemoresistance and tumor relapse. The heterogeneity of HCC is an important attribute of the disease. It is the outcome of many factors, including the cross-talk between tumor cells within the tumor microenvironment and the acquisition and accumulation of genetic and epigenetic alterations in tumor cells. In addition, there is accumulating evidence in recent years to show that the malignancy of HCC can be attributed partly to the presence of cancer stem cell (CSC). CSCs are capable to self-renew, differentiate and initiate tumor formation. The regulation of the stem cell-like properties by several important signaling pathways have been found to endow the tumor cells with an increased level of tumorigenicity, chemoresistance, and metastatic ability. In this review, we will discuss the recent findings on hepatic CSCs, with special emphasis on their putative origins, relationship with hepatitis viruses, regulatory signaling networks, tumor microenvironment, and how these factors control the stemness of hepatic CSCs. We will also discuss some novel therapeutic strategies targeted at hepatic CSCs for combating HCC and perspectives of future investigation.

Mutational Analysis of the MTHFR Gene in Breast Cancer Patients of Pakistani Population

  • Akram, Muhammad;Malik, Fa;Kayani, Mahmood Akhtar
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.4
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    • pp.1599-1603
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    • 2012
  • Objectives: Since methylenetetrahydrofolate reductase (MTHFR) maintains the balance of circulating folate and methionine and blocks the formation of homocysteine, its regulation in relation to different cancers has extensively been studied in different populations. However, information on Pakistani breast cancer patients is lacking. The MTHFR gene has two most common mutations that are single nucleotide additions which result in change of amino acids C677T to Ala222val and A1298C to Glu429Ala. Methodology: 110 sporadic breast patients with no prior family history of cancer or any other type of genetic disorders along with 110 normal individuals were screened for mutations in exons 1 to exon 9 using single strand conformational polymorphism, RFLP and sequencing analyzer. Results: The p values for the 677CC, 677CT, and 677TT genotypes were 0.223, 0.006, and 0.077, respectively. Those for the 1298AA, 1298AC, and 1298CC genotypes were 0.555, 0.009, and 0.003, respectively. Conclusions: We found an overall a significant, weak inverse association between breast cancer risk and the 677TT genotype and an inverse association with the 1298C variant. These results for MTHFR polymorphism might be population specific in sporadic breast cancer affected patients but many other factors need to be excluded before making final conclusions including folate intake, population and disease heterogeneity.

Screening of SHOX gene sequence variants in Saudi Arabian children with idiopathic short stature

  • Alharthi, Abdulla A.;El-Hallous, Ehab I.;Talaat, Iman M.;Alghamdi, Hamed A.;Almalki, Matar I.;Gaber, Ahmed
    • Clinical and Experimental Pediatrics
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    • v.60 no.10
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    • pp.327-332
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    • 2017
  • Purpose: Short stature affects approximately 2%-3% of children, representing one of the most frequent disorders for which clinical attention is sought during childhood. Despite assumed genetic heterogeneity, mutations or deletions in the short stature homeobox-containing gene (SHOX ) are frequently detected in subjects with short stature. Idiopathic short stature (ISS) refers to patients with short stature for various unknown reasons. The goal of this study was to screen all the exons of SHOX to identify related mutations. Methods: We screened all the exons of SHOX for mutations analysis in 105 ISS children patients (57 girls and 48 boys) living in Taif governorate, KSA using a direct DNA sequencing method. Height, arm span, and sitting height were recorded, and subischial leg length was calculated. Results: A total of 30 of 105 ISS patients (28%) contained six polymorphic variants in exons 1, 2, 4, and 6. One mutation was found in the DNA domain binding region of exon 4. Three of these polymorphic variants were novel, while the others were reported previously. There were no significant differences in anthropometric measures in ISS patients with and without identifiable polymorphic variants in SHOX. Conclusion: In Saudi Arabia ISS patients, rather than SHOX, it is possible that new genes are involved in longitudinal growth. Additional molecular analysis is required to diagnose and understand the etiology of this disease.

Epidermolysis Bullosa with Mouth Opening Limitation (개구제한을 동반한 수포성 표피박리증)

  • Yun, Yeong-Eun;Kim, Jae-Young;Lee, Dong-Keun;Kang, Ji-Yeon
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.34 no.2
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    • pp.117-126
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    • 2012
  • Epidermolysis bullosa (EB) represents a spectrum of conditions that are characterized by blistering and mechanical fragility of the skin. There is genetic heterogeneity and marked variation in clinical phenotypes in the multiple EB disorders. The most recent classification recognizes four major EB grouping and over 30 EB subtypes. The severity of EB ranges from mild to severe skin involvement, and it can be localized or generalized. Oral features include repeated occurrence of blisters, erosions, and scars, which lead to limited mouth opening, ankyloglossia, elimination of buccal vestibule, and increased risk of oral carcinoma. Routine dental care or even normal tooth brushing might cause bullae on the oral mucosa. Occasionally, the clinician will be called upon to treat patients with EB and should therefore be aware of specific treatment modifications. we present a reviews of the literature with a case providing adequate anesthetic and surgical care.

Insight into the pathogensis of polycystic ovarian syndrome

  • Jung, Yong Wook;Lee, Gun Ho;Han, You Jung;Cha, Dong Hyun
    • Journal of Genetic Medicine
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    • v.17 no.1
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    • pp.1-10
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    • 2020
  • Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder in women, which is characterized by the oligo/anovulation, hyperandrogenism (HA) and polycystic ovarian morphology which are diagnostic criteria. PCOS has diverse clinical aspects in addition to those diagnostic criteria including increased risk for cardiovascular diseases, metabolic syndrome, dyslipidemia, type 2 diabetes and impaired fertility. Because of the heterogeneity of the disease, the pathogenesis of the disease has not been elucidated yet. Therefore, there is no cure for the endocrinopathy. HA and insulin resistance (IR) has been considered two major pillars of the pathogenesis of PCOS. Recent advances in animal studies revealed the critical role of neuroendocrine abnormalities in developing PCOS. Several pathways related to neuroendocrine origin have been investigated such as hypothalamus pituitary ovarian axis, hypothalamus pituitary adrenal axis and hypothalamus pituitary adipose axis. This review summarizes the current knowledge about the role of HA and IR in developing PCOS. In addition, we review the results of recent genome wide association studies for PCOS. This new perspective improves our understanding of the role of neuroendocrine origins in PCOS and suggest a novel potential therapeutic target for the treatment of PCOS.

Development of Automatic SWAT Calibration Algorithm Using NSGA-II Algorithm (NSGA-II를 활용한 SWAT 모형의 검보정 알고리즘 개발)

  • Lee, Yong Gwan;Jung, Chung Gil;Kim, Se Hoon;Kim, Seong Joon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2018.05a
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    • pp.34-34
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    • 2018
  • 본 연구는 다목적 유전자 알고리즘 Non-Dominated Sorting Genetic Algorithm II (NSGA-II)를 활용하여 자동 검보정 알고리즘을 개발하고, 이를 준분포형 수문모형인 SWAT (Soil and Water Assessment Tool) 모형에 적용하여 평가하고자 한다. 집중형 모형과 달리, 분포형 모형은 유역 내 다양한 물리적 변수와 공간 이질성(spatial heterogeneity)을 표현하기 위한 많은 매개변수를 포함하고 있고, 최근에는 기후 변화와 장기 가뭄과 같은 이상 기후에 따른 물 부족, 수질 오염 및 녹조 현상 등을 고려하기 위해 매개변수의 시간적인 변동성을 고려하기 위한 연구도 수행되고 있다. 이에 따라 본 연구에서 개발한 다목적 알고리즘은 다양한 매개변수의 시공간적 특성을 고려할 수 있도록 작성되었으며, Python으로 개발하여 타 모형으로의 확장성 및 범용성을 고려하였다. SWAT 모형의 유출 해석은 결정계수(Coefficient of determination, $R^2$), RMSE(Root mean square error), 모형 효율성 계수(Nash-Sutcliffe efficiency, NSE) 및 IOA(Index of agreement) 등을 활용해 기존 연구 결과와 비교분석할 수 있도록 하였으며, 사용자의 선택에 따라 다른 목적함수 또한 활용할 수 있도록 하였다. NSGA-II를 활용한 SWAT 모형의 유출 해석은 다목적 함수를 고려함에 따라 실측값과 높은 상관성을 보여줄 것으로 판단되며, 이상 기후 기간 설정에 따른 유동적인 매개변수 변화를 적용할 수 있을 것으로 기대된다.

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Twenty-one-year follow-up of variable onset MELAS syndrome with heteroplasmic nt3243A>G mtDNA mutation: A case report

  • Song, Wung Joo;Lee, Yoon Jin;Kang, Joon Won;Chang, Mea Young;Song, Kyu Sang;Kang, Dae Young;Kim, Sook Za
    • Journal of Genetic Medicine
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    • v.16 no.1
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    • pp.31-38
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    • 2019
  • Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome is a maternally inherited mitochondrial disorder of which m.3243A>G is the most commonly associated mutation, resulting in an inability to meet the energy requirements of various organs. MELAS poses a diagnostic challenge owing to its multiple organ involvement and great clinical variability due to its heteroplasmic nature. We report three cases from a family who were initially misdiagnosed with myasthenia gravis or undiagnosed. Although there is no optimal consensus treatment approach for patients with MELAS because of the disease's heterogeneity, our 21-year-long therapy regimen of ${\text\tiny{L}}-arginine$, ${\text\tiny{L}}-carnitine$, and coenzyme Q10 supplementation combined with dietary management appeared to provide noticeable protection from the symptoms and complications. Prompt early diagnosis is important, as optimal multidisciplinary management and early intervention may improve outcomes.

Association Between the GSTP1 Codon 105 Polymorphism and Gastric Cancer Risk: an Updated Meta-analysis

  • Bao, Li-Dao;Niu, Jian-Xiang;Song, Hui;Wang, Yi;Ma, Rui-Lian;Ren, Xian-Hua;Wu, Xin-Lin
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.8
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    • pp.3687-3693
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    • 2012
  • Objective: The current meta-analysis was performed to address a more accurate estimation of the association between glutathione S-transferase P1 (GSTP1) codon 105 polymorphism and risk of gastric cancer (GC), which has been widely reported with conflicting results. Methods: A comprehensive literature search was conducted to identify all the relevant studies. Fixed or random effect models were selected based on the heterogeneity test. Publication bias was estimated using Begg's funnel plots and Egger's regression test. Results: A total of 20 studies containing 2,821 GC cases and 6,240 controls were finally included in the analyses. Overall, no significant association between GSTP1 polymorphism and GC risk was observed in worldwide populations. However, subgroup analysis stratified by ethnicity showed that GSTP1 polymorphism was significantly associated with increased risk of GC in Asians (G vs. A, OR = 1.273, 95%CI=1.011-1.605; GG vs. AA, OR=2.103, 95%CI=1.197-3.387; GG vs. AA+AG, OR =2.103, 95%CI=1.186-3.414). In contrast, no significant association was found in Caucasians in any genetic models, except for with AG vs. AA (OR=0.791, 95%CI=0.669-0.936). Furthermore, the GSTP1 polymorphism was found to be significantly associated with GC in patients with H. pylori infection and in those with a cardiac GC. Subgroup analysis stratified by Lauren's classification and smoking status showed no significant association with any genetic model. No studies were found to significantly influence the pooled effects in each genetic mode, and no potential publication bias was detected. Conclusion: This meta-analysis suggested that the GSTP1 polymorphism might be associated with increased risk of GC in Asians, while GSTP1 heterozygote genotype seemed to be associated with reduced risk of GC. Since potential confounders could not be ruled out completely, further studies are needed to confirm these results.

Genetic Polymorphisms of Candidate Loci and Inheritance Ppatterns of Gray Coat Color in Jeju Horses. (제주마에서 총마 모색의 유전 양성과 후보 유전좌위의 유전적 다형성)

  • Han, Sang-Hyun;Lee, Chong-Eon;Kim, Nam-Young;Ko, Moon-Suck;Jeong, Ha-Yeon;Lee, Sung-Soo
    • Journal of Life Science
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    • v.19 no.6
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    • pp.793-798
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    • 2009
  • This study was undertaken to reveal the relationship between genetic variations and inheritance patterns and the development of a systemic white coat color frequently observed in Jeju horses. It was determined that the white coat color occurred in all basic coat colored (black, bay and chestnut) horses by combining the phenotype and MC1R genotypes. There were no polymorphisms found in Jeju horses tested for mutational loci in the KIT gene, which were previously reported as potential mutations of the congenital dominant white coat color in other horse breeds in heterogeneity. The horses that had the 4.6-kb duplication in the STX17 intron 6 specifically showed the depigmented white coat color. Based on observation and STX17 genotypes, this depigmented whitening is defined as 'Chongma' (whitening, progressive graying with age-Gray) in Jeju horses. Pedigrees showed that this is an autosomal dominant inheritance pattern distinct from the bovine albinism caused by an autosomal recessive passion eye color. Because the gray phenotype is generally not completely expressed early in Jeju horses, it often makes them indistinguishable from other horses. Further studies are recommended for classification between the gray coat color and its similar phenotypes, such as the roan with its mixed hair colors appearing since neonatal period, acquired white hairs on wounded skin by veterinary treatment, and vitiligo-like skin pigmentation. However, study results revealing the relationship between the gray phenotype and genetic background suggested that useful information may be provided in regards to molecular breeding of Jeju horses.

Genetic Variation in the Immunoregulatory Gene of Adenovirus Type 3 (3형 아데노바이러스의 면역조절 유전자 다양성)

  • Choi, Eun Hwa;Kim, Hee Sup;Lee, Hoan Jong
    • Pediatric Infection and Vaccine
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    • v.16 no.2
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    • pp.199-204
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    • 2009
  • Purpose : Various proteins encoded in the early region 3 (E3) of adenoviruses protect cells from being killed by cytotoxic T cells and death-inducing cytokines. We sought to find out whether the genetic heterogeneity of the E3 gene might contribute to the molecular diversity of adenoviruses. Methods : Sequences in the E3 region were analyzed for 14 adenovirus type 3 (Ad3) strains that were isolated from children with lower respiratory tract infections in the Seoul National University Children's Hospital during the period 1991-2000. Full-length adenoviral DNA was purified from the infected A549 cell lysates using a modified Hirt procedure. Results : There was 98% homology between 14 Korean Ad3 strains with a reference strain (M15952). Homology within the Korean Ad3 strains was 98.7%. Variation was found in the region of transcripts 20.1 kDa, 20.6 kDa, truncated 7.7 kDa, 10.3 kDa, 14.9 kDa, and 15.3 kDa. In particular, all 14 Korean strains showed a missense single point mutation at the start codon of the truncated 7.7 kDa. In addition, a deletion was found in the truncated 7.7 kDa region by 58 base pairs in 10 strains and 94 base pairs in 4 strains. Variations in amino acids were observed in the receptor internalization and degradation complex (10.3 kDa/14.9 kDa) which stimulates the clearance from the cell surface and subsequent degradation of the receptors for the Fas ligand and TRAIL, while no variations were observed in another immunoregulatory transcript, 19 kDa. Conclusion : Sequence analysis of the immunoregulatory region of adenovirus E3 shows that genetic heterogeneities are related to genome type patterns.

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