• Asian Pacific Journal of Cancer Prevention
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• v.17 no.7
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• pp.3035-3041
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• 2016

Breast cancer (BC) is the most common malignancy of women worldwide. In the past it was considered as disease of older middle aged women, but the incidence of BC in young females is growing in recent years concordant with studies in Pakistan. In this paper, we reviewed the mutant functions of tumor suppressor genes (BRCA1, BRCA2, p53, ATM and PTEN), epigenetic transformation and involvement of estrogen receptors in development of breast cancer. We further reviewed the current situation of BC in Pakistan that depicts a higher incidence in young females. According to SKMCH and RC data, age group 45-49 years is more prone to BC with high rate of incidence 45.42%. A few studies explored the high expression of ER, PR and HER-2/neu in Pakistani females. Moreover, presence of BRCA1 (c.1961dupA) mutation in Pakistani shows concordance with data in different areas of world. But we are unable to find an authentic study that can explore epigenetic based transformation of breast tumors in Pakistan. This area of research needs more attention to explore the complete picture of BC in Pakistan.

• Clinical and Experimental Reproductive Medicine
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• v.43 no.2
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• pp.59-81
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• 2016

It is well established that there is a heritable element of susceptibility to chronic human ailments, yet there is compelling evidence that some components of such heritability are transmitted through non-genetic factors. Due to the complexity of reproductive processes, identifying the inheritance patterns of these factors is not easy. But little doubt exists that besides the genomic backbone, a range of epigenetic cues affect our genetic programme. The inter-generational transmission of epigenetic marks is believed to operate via four principal means that dramatically differ in their information content: DNA methylation, histone modifications, microRNAs and nucleosome positioning. These epigenetic signatures influence the cellular machinery through positive and negative feedback mechanisms either alone or interactively. Understanding how these mechanisms work to activate or deactivate parts of our genetic programme not only on a day-to-day basis but also over generations is an important area of reproductive health research.

• Genomics & Informatics
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• v.11 no.4
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• pp.164-173
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• 2013

Genomic instability, which occurs through both genetic mechanisms (underlying inheritable phenotypic variations caused by DNA sequence-dependent alterations, such as mutation, deletion, insertion, inversion, translocation, and chromosomal aneuploidy) and epigenomic aberrations (underlying inheritable phenotypic variations caused by DNA sequence-independent alterations caused by a change of chromatin structure, such as DNA methylation and histone modifications), is known to promote tumorigenesis and tumor progression. Mechanisms involve both genomic instability and epigenomic aberrations that lose or gain the function of genes that impinge on tumor suppression/prevention or oncogenesis. Growing evidence points to an epigenome-wide disruption that involves large-scale DNA hypomethylation but specific hyper-methylation of tumor suppressor genes, large blocks of aberrant histone modifications, and abnormal miRNA expression profile. Emerging molecular details regarding the modulation of these epigenetic events in cancer are used to illustrate the alterations of epigenetic molecules, and their consequent malfunctions could contribute to cancer biology. More recently, intriguing evidence supporting that genetic and epigenetic mechanisms are not separate events in cancer has been emerging; they intertwine and take advantage of each other during tumorigenesis. In addition, we discuss the collusion between epigenetics and genetics mediated by heterochromatin protein 1, a major component of heterochromatin, in order to maintain genome integrity.

• BMB Reports
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• v.55 no.7
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• pp.342-347
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• 2022

Defense priming allows plants to enhance their immune responses to subsequent pathogen challenges. Recent reports suggested that acquired resistances in parental generation can be inherited into descendants. Although epigenetic mechanisms are plausible tools enabling the transmission of information or phenotypic traits induced by environmental cues across generations, the mechanism for the transgenerational inheritance of defense priming in plants has yet to be elucidated. With the initial aim to elucidate an epigenetic mechanism for the defense priming in plants, we reassessed the transgenerational inheritance of plant defense, however, could not observe any evidence supporting it. By using the same dipping method with previous reports, Arabidopsis was exposed repeatedly to Pseudomonas syringae pv tomato DC3000 (Pst DC3000) during vegetative or reproductive stages. Irrespective of the developmental stages of parental plants that received pathogen infection, the descendants did not exhibit primed resistance phenotypes, defense marker gene (PR1) expression, or elevated histone acetylation within PR1 chromatin. In assays using the pressure-infiltration method for infection, we obtained the same results as above. Thus, our results suggest that the previous observations on the transgenerational inheritance of defense priming in plants should be more extensively and carefully reassessed.

• 한국균학회소식:학술대회논문집
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• 2014.10a
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• pp.11-11
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• 2014

Fungal pathogens have huge impact on health and economic wellbeing of human by causing life-threatening mycoses in immune-compromised patients or by destroying crop plants. A key determinant of fungal pathogenesis is their ability to undergo developmental change in response to host or environmental factors. Genetic pathways that regulate such morphological transitions and adaptation are therefore extensively studied during the last few decades. Given that epigenetic as well as genetic components play pivotal roles in development of plants and mammals, contribution of microbial epigenetic counterparts to this morphogenetic process is intriguing yet nearly unappreciated question to date. To bridge this gap in our knowledge, we set out to investigate histone modifications among epigenetic mechanisms that possibly regulate fungal adaptation and processes involved in pathogenesis of a model plant pathogenic fungus, Magnaporthe oryzae. M. oryzae is a causal agent of rice blast disease, which destroys 10 to 30% of the rice crop annually. Since the rice is the staple food for more than half of human population, the disease is a major threat to global food security. In addition to the socioeconomic impact of the disease it causes, the fungus is genetically tractable and can undergo well-defined morphological transitions including asexual spore production and appressorium (a specialized infection structure) formation in vitro, making it a model to study fungal development and pathogenicity. For functional and comparative analysis of histone modifications, a web-based database (dbHiMo) was constructed to archive and analyze histone modifying enzymes from eukaryotic species whose genome sequences are available. Histone modifying enzymes were identified applying a search pipeline built upon profile hidden Markov model (HMM) to proteomes. The database incorporates 22,169 histone-modifying enzymes identified from 342 species including 214 fungal, 33 plants, and 77 metazoan species. The dbHiMo provides users with web-based personalized data browsing and analysis tools, supporting comparative and evolutionary genomics. Based on the database entries, functional analysis of genes encoding histone acetyltransferases and histone demethylases is under way. Here I provide examples of such analyses that show how histone acetylation and methylation is implicated in regulating important aspects of fungal pathogenesis. Current analysis of histone modifying enzymes will be followed by ChIP-Seq and RNA-seq experiments to pinpoint the genes that are controlled by particular histone modifications. We anticipate that our work will provide not only the significant advances in our understanding of epigenetic mechanisms operating in microbial eukaryotes but also basis to expand our perspective on regulation of development in fungal pathogens.

• Proceedings of the Korean Society of Developmental Biology Conference
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• 2003.02a
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• pp.6-6
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• 2003

No Abstract, See Full Text

• 대한생식의학회:학술대회논문집
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• 1999.05a
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• pp.21-23
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• 1999

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2249-2250
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• 2013

• 대한생식의학회:학술대회논문집
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• 2006.06a
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• pp.92-94
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• 2006

• Molecules and Cells
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• v.24 no.3
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• pp.441-444
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• 2007

Despite the importance of cell fate decisions regulated by epigenetic programming, no experimental model has been available to study transdifferentiation from myoblasts to smooth muscle cells. In the present study, we show that myoblast cells can be induced to transdifferentiate into smooth muscle cells by modulating their epigenetic programming. The DNA methylation inhibitor, zubularine, induced the morphological transformation of C2C12 myoblasts into smooth muscle cells accompanied by de novo synthesis of smooth muscle markers such as smooth muscle ${\alpha}$-actin and transgelin. Furthermore, an increase of p21 and decrease of cyclinD1 mRNA were observed following zebularine treatment, pointing to inhibition of cell cycle progression. This system may provide a useful model for studying the early stages of smooth muscle cell differentiation.