Carcinogenesis Research Research Articles

Resistance against the development of diethylnitrosamine-induced hepatocellular carcinoma in female C3H mice: an experimental model.

Histopathological features of hepatocellular carcinoma (HCC) induced by diethylnitrosamine (DEN) in mice display strong similarities with those seen in humans, including the higher tumor prevalence in males than in females. Previous studies have demonstrated that continual production of the pro-inflammatory IL-6 by Kupffer cells is involved in the initiation and progression of DEN-induced HCC and that estrogen-mediated reduction of IL-6 secretion would decrease its incidence in females. Given the predominant utilization of male mice in hepatic carcinogenesis research, the objective of this study was to examine histopathological and immunological parameters in the DEN-induced liver carcinogenesis model in female C3H mice. We observed a significant prevalence of hepatocellular hyperplasias and adenomas alongside a minimal infiltration of inflammatory cells and a scarcity of senescent areas in females. Further, a low expression of immunosuppression markers is observed in females - such as neutrophil/lymphocyte ratio, PD-1 expression in CD8 T cells, and PD-L1 in myeloid cells - compared to males. Comparative studies between susceptible and resistant hosts to chemical carcinogenesis may help to unveil novel therapeutic strategies against cancer.

Pre and Postoperative Serum miR-21 Expression Levels in Oral Cancer and it’s Association with Clinical and Histological Parameters: An Observational Study

Introduction: The patterns of microRNA (miRNA) expression have opened up new avenues in the search for prognostic biomarkers and potential therapeutic targets for various tumours. In oral carcinogenesis research, analysing microRNAs expressed in Oral Squamous Cell Carcinoma (OSCC) unveils a complex network of interest. miR-21 is known to be overexpressed in numerous solid tumours and is linked to the progression of malignancies in hepatocellular carcinomas, breast cancer, and colon carcinomas. Aim: To determine the impact of surgical excision on serum miR-21 expression levels in OSCC cases and to establish correlations with clinicopathological parameters. Materials and Methods: The study was an exploratory prospective observational study conducted with proper institutional ethical approval at the Cancer Research Institute (CRI), Himalayan Institute of Medical Sciences (HIMS), Jolly Grant, Dehradun, Uttarakhand, India. Fifty-six histologically confirmed OSCC cases were enrolled along with 25 healthy subjects as controls from May 2021 to June 2023. The relative fold expression change was calculated using the Livak method (2-∆∆ct). Data analysis was performed using software such as Statistical Package for Social Sciences (SPSS) version 20.0 and MS Excel. Non parametric statistical tests such as Wilcoxon signed-rank test, MannWhitney test, and Kruskal-Wallis test were utilised. Results: Out of 56 sample included, 28 exhibited high expression of miR-21 (p-value<0.001), while 27 cases showed downregulation postsurgery (p-value<0.001), with one sample showing the same level of expression. In cases where the time difference between pre and postsurgery samples was over 25 days, no significant change was observed (p-value=0.06), and similarly, in cases with a time difference below 25 days, no significant difference was noted (p-value=0.14). A significant negative correlation was found between presurgery serum Albumin to Globulin ratio (A:G ratio) and miR-21 expression (p-value <0.05), while no other parameters showed a significant correlation with miR-21. Conclusion: miR-21 expression decreased significantly in some OSCC cases; however, in the majority of cases, it increased postsurgery. A significant correlation was observed between miR-21 expression and the serum A:G ratio.

Ionizing radiation-induced cancer: perplexities of the bystander effect.

Ionizing radiation (IR) is a carcinogen. This has been established beyond doubt from many years of studies such as those conducted among the survivors of the atomic bomb attacks on Hiroshima and Nagasaki and later from the Chernobyl accident. Despite immense progress in the field of carcinogenesis, complete understanding of the underlying mechanisms behind IR-induced cancer remains elusive. In particular, the long gestation period between exposure to IR and the onset of cancer, frequently unpredictable, and sometimes lasting for many years, remains poorly understood. The centrality of DNA damage and misrepair in carcinogenesis research has not entirely benefited IR-induced cancer research and the past decade has seen a shift in understanding radiation-driven cellular mechanisms beyond simplistic models of targeted DNA damage. This paper presents a viewpoint on the gaps in our knowledge of IR-induced cancer with a focus on the non-targeted bystander effect, the mechanisms underlying which may be key to radiotherapeutic advances.

The Local Microbiome in Esophageal Cancer and Treatment Response: A Review of Emerging Data and Future Directions.

peer-reviewed, published studies describing the role of local, gastrointestinal-specific microbiota or the role of the gut microbiome in treatment responses were reviewed. PubMed was searched from 1 September 2022 to 1 November 2022, using the following terms in combination: "microbiome", "tumor microbiome", "esophageal cancer", "cancer", "cancer treatment", and "immunotherapy". Original research articles were considered, and other reviews or editorials were discarded. In total, approximately 250 articles were considered. over 70 studies describing microbiome research in either gastrointestinal carcinogenesis or the systemic treatment response were identified and reviewed. a growing body of evidence supports the role of the esophageal microbiome in both esophageal tumorigenesis and the immune checkpoint inhibitor response. More well-designed, comprehensive studies are required to collect the appropriate clinical, microbial, and immunophenotype data that are needed to clarify the precise role of the microbiome in esophageal carcinogenesis and treatment.

Next Generation Sequencing Workshop at the Royal Society of Medicine (London, May 2022): how genomics is on the path to modernizing genetic toxicology.

The use of error-corrected Next Generation Sequencing (ecNG) to determine mutagenicity has been a subject of growing interest and potentially a disruptive technology that could supplement, and in time, replace current testing paradigms in preclinical safety assessment. Considering this, a Next Generation Sequencing Workshop was held at the Royal Society of Medicine in London in May 2022, supported by the United Kingdom Environmental Mutagen Society (UKEMS) and TwinStrand Biosciences (WA, USA), to discuss progress and future applications of this technology. In this meeting report, the invited speakers provide an overview of the Workshop topics covered and identify future directions for research. In the area of somatic mutagenesis, several speakers reviewed recent progress made with correlating ecNGS to classic in vivo transgenic rodent mutation assays as well as exploring the use of this technology directly in humans and animals, and in complex organoid models. Additionally, ecNGS has been used for detecting off-target effects of gene editing tools and emerging data suggest ecNGS potential to measure clonal expansion of cells carrying mutations in cancer driver genes as an early marker of carcinogenic potential and for direct human biomonitoring. As such, the workshop demonstrated the importance of raising awareness and support for advancing the science of ecNGS for mutagenesis, gene editing, and carcinogenesis research. Furthermore, the potential of this new technology to contribute to advances in drug and product development and improve safety assessment was extensively explored.

Single‐cell nucleic acid sequencing reinforces to reveal signal‐ dependent pathways contributing to cellular heterogeneity

Single‐cell nucleic acid sequencing reinforces to reveal signal‐ dependent pathways contributing to cellular heterogeneity

Discovering biomarkers for hormone-dependent tumors: in silico study on signaling pathways implicated in cell cycle and cytoskeleton regulation.

Malignancies dependent on hormone homeostasis include breast, ovary, cervical, prostate, testis and uterine tumors. Hormones are involved in signal transduction which orchestrate processes, such as apoptosis, proliferation, cell cycle or cytoskeleton organization. Currently, there is a need for novel biomarkers which would help to diagnose cancers efficiently. In this study, the genes implicated in signaling that is important in hormone-sensitive carcinogenesis were investigated regarding their prognostic significance. Data of seven cancer cohorts were collected from FireBrowse. 54 gene sets implicated in specific pathways were browsed through MSig database. Profiling was assessed via Monocle3, while gene ontology through PANTHER. For confirmation, correlation analysis was performed using WGCNA. Protein-protein networks were visualized via Cytoscape and impact of genes on survival, as well as cell cycle or cytoskeleton-related prognostic signatures, was tested. Several differences in expression profile were identified, some of them allowed to distinguish histology. Functional annotation revealed that various regulation of cell cycle, adhesion, migration, apoptosis and angiogenesis underlie these differences. Clinical traits, such as histological type or cancer staging, were found during evaluation of module-trait relationships. Of modules, the TopHubs (COL6A3, TNR, GTF2A1, NKX3-1) interacted directly with, e.g., PDGFB, ITGA10, SP1 or AKT3. Among TopHubs and interacting proteins, many showed an impact on hazard ratio and affected the cell cycle or cytoskeleton-related prognostic signatures, e.g., COL1A1 or PDGFB. In conclusion, this study laid the foundation for further hormone-sensitive carcinogenesis research through identification of genes which prove that crosstalk between cell cycle and cytoskeleton exists, opening avenues for future therapeutic strategies.

Women in toxicology in the United States.

Since the toxicology field was established, women have played a critical role in it. This article is written to celebrate the 20-year anniversary of the Special Interest Group for Women in Toxicology, affiliated with the Society of Toxicology. Six female pioneers in modern Toxicology from different social classes and education backgrounds are featured. Despite these differences, they overcame similar obstacles in gender, politics, and scientific barriers to disseminate their research. This discussion will start with Ellen Swallow Richards, who, besides being the pioneer in sanitary engineering, founded the home economics movement that applied science to the home. The discussion will continue with Alice Hamilton, a contributor to occupational health, a pioneer in the field of industrial toxicology, and an example of generosity to social movements and those in need. Subsequently, the most famous woman we discuss in this paper is Rachel Carson, whose fundamental work in environmental Toxicology is evidenced in her important book Silent Spring. This article also features Elizabeth Miller, a biochemist known for her fundamental research in cancer carcinogenesis, followed by Mary Amdur. Nowadays much of what we know about air pollution comes due to Mary, who paid from her own pocket for her experimental animals to investigate Donora smog pollutants and their health damages. And last but not least Elizabeth Weisburger, a chemist who made significant contributions in carcinogenesis and chemotherapy drugs who worked for 40 years at the National Cancer Institute. Here, we discuss the aforementioned women's careers and personal struggles that transformed toxicology into the field we know now.

Direct Alkylation of Deoxyguanosine by Azaserine Leads to O6-Carboxymethyldeoxyguanosine.

The O6-alkylguanosine adduct O6-carboxymethyldeoxyguanosine (O6-CMdG) has been detected at elevated levels in blood and tissue samples from colorectal cancer patients and from healthy volunteers after consuming red meat. The diazo compound l-azaserine leads to the formation of O6-CMdG as well as the corresponding methyl adduct O6-methyldeoxyguanosine (O6-MedG) in cells and is therefore in wide use as a chemical probe in cellular studies concerning DNA damage and mutation. However, there remain knowledge gaps concerning the chemical basis of DNA adduct formation by l-azaserine. To characterize O6-CMdG formation by l-azaserine, we carried out a combination of chemical and enzymatic stability and reactivity studies supported by liquid chromatography tandem mass spectrometry for the simultaneous quantification of O6-CMdG and O6-MedG. We found that l-azaserine is stable under physiological and alkaline conditions as well as in active biological matrices but undergoes acid-catalyzed hydrolysis. We show, for the first time, that l-azaserine reacts directly with guanosine (dG) and oligonucleotides to form an O6-serine-CMdG (O6-Ser-CMdG) adduct. Moreover, by characterizing the reaction of dG with l-azaserine, we demonstrate that O6-Ser-CMdG forms as an intermediate that spontaneously decomposes to form O6-CMdG. Finally, we quantified levels of O6-CMdG and O6-MedG in a human cell line exposed to l-azaserine and found maximal adduct levels after 48 h. The findings of this work elucidate the chemical basis of how l-azaserine reacts with deoxyguanosine and support its use as a chemical probe for N-nitroso compound exposure in carcinogenesis research, particularly concerning the identification of pathways and factors that promote adduct formation.

Quantitative structure\u2013activity relationship models for genotoxicity prediction based on combination evaluation strategies for toxicological alternative experiments

Mutagenicity exerts adverse effects on humans. Conventional methods cannot simultaneously predict the toxicity of a large number of compounds. Most mutagenicity prediction models are based on a single experimental type and lack other experimental combination data as support, resulting in limited application scope and predictive ability. In this study, we partitioned data from GENE-TOX, CPDB, and Chemical Carcinogenesis Research Information System according to the weight-of-evidence method for modelling. In our data set, in vivo and in vitro experiments in groups as well as prokaryotic and eukaryotic cell experiments were included in accordance with the ICH guideline. We compared the two experimental combinations mentioned in the weight-of-evidence method and reintegrated the experimental data into three groups. Nine sub-models and three fusion models were established using random forest (RF), support vector machine (SVM), and back propagation (BP) neural network algorithms. When fusing base models under the same algorithm according to the ensemble rules, all models showed excellent predictive performance. The RF, SVM, and BP fusion models reached a prediction accuracy rate of 83.4%, 80.5%, 79.0% respectively. The area under the curve (AUC) reached 0.853, 0.897, 0.865 respectively. Therefore, the established fusion QSAR models can serve as an early warning system for mutagenicity of compounds.

Antitumour Activity of Dehydroxymethylepoxyquinomycin (DHMEQ): a Literature Review

Carcinogenesis research uncovers new pathogenesis links as vulnerable targets of effective antitumour therapies. Among the key mediators of immune response, cell proliferation, cell apoptosis and inflammation is transcription factor NF-κB. Misregulation of an NF-κB-dependent pathway is found in solid and haematopoietic tumour cells. One of the best known NF-κB functions is expression regulation of genes involved in the apoptosis inhibition or activation and survival in both intact and malignant cells. The NF-κB-mediated pathways’ involvement in carcinogenesis, angiogenesis and tumour resistance to chemo- and radiotherapies makes this factor a promising target for drug anti-cancer interventions. This review summarises evidence on the antitumour and anti-inflammatory activity of a high-potent and specific low molecular-weight NF-κB inhibitor, dehydroxymethylhepoxyquinomycin (DHMEQ), as a candidate therapeutic agent in treatment for variant malignancies.

A clear cancer cell line (150057) derived from human endometrial carcinoma harbors two novel mutations

BackgroundCell lines are extremely useful for both basic and clinical research. Thus, establishing endometrial cancer cell lines with malignant histology is important. This study aimed to extensively characterize an endometrial clear cell carcinoma cell line.MethodsThis cell line, named 150,057, was derived from the endometrial clear cell cancer of a 63-year-old woman. The morphology, chromosomes, chemosensitivity, tumor markers, xenotransplantation characteristics, and cancer-related genes of the cell line were characterized.ResultsThis cell line exhibited adequate growth, being passaged more than 70 times. The morphology of the cells was polygonal with a cobblestone-like appearance. Karyotyping of the cell line revealed a hypodiploid chromosomal number. 150057 cells expressed CA19–9 and CA125. The cell line was sensitive to doxorubicin, paclitaxel, carboplatin, and cisplatin. After the cells were transplanted into the subcutaneous region of non-obese diabetic-severe combined immunodeficiency mice, they generated xenograft tumors with similar histology as the original tumor. A total of 59 somatic nucleotide mutations were identified in 25 of the 53 examined tumor suppressor genes and oncogenes. Two novel mutations were found in FGFR3 and ARID1A.ConclusionWe established and characterized an endometrial clear cell carcinoma cell line that may be useful in carcinogenesis and treatment research for endometrial cancer.

To Study theAnti-cancer Effects of Shigella Flexneri in AspC-1 Pancreatic Cancer Cell Line in Approach to Bax and bcl-2 Genes.

Cancer is the uncontrolled division of cells and can be caused by genetic or environmental factors. Pancreatic cancer is one of the deadliest among all cancers. The role of bacteria as an anticancer agent dates back to almost 100years ago. The microbiome has recently become a focus of research in carcinogenesis and even pancreatic cancer. Shigella flexneri is a gram-negative bacterium, which causes shigellosis with symptoms such as diarrhea, fever, and stomach cramps in human. Shigella flexneri may play a very important role in the internal pathways of apoptosis and may induce apoptosis in some of the cancerous cells. In this experiment bacteria were cultured on Salmonella-Shigella agar, then inoculated into BHI Broth medium. After sonication, the protein concentration of the bacterium was measured by using the ZellBio Sensitive Protein Bradford Assay kit. MTT assay was performed to obtain IC50 for the said bacterial protein. Later by cDNA kit synthesized the cDNA based on the RNA template. In the end, the results were analyzed using real-time PCR and the expression of Bax and Bcl-2 genes was measured before and after treatment. The results showed that Shigella flexneri has the potential anti-proliferative effect in pancreatic cancer. The inhibitory concentration, pro-apoptotic amount to upregulate Bax, and meanwhile also to downregulate the bcl-2 found to be 10μl. In general, due to defects in the apoptotic pathway in cancer cells and the existence of drug-resistant cells, the detection of new apoptotic inducers such as Shigella flexneri cell extract can be used for further studies on cancer therapy.

Abstract P5-11-20: Efficacy observation of 306 patients with fulvestrant 500mg treatment in hormone-receptor positive HER2 negative metastasis breast cancer, a real world study

Abstract Background: Fulvestrant 500mg has been proved better efficacy in breast cancer with hormone receptor positive (HR+),and then become an optional strategy for primary or second line treatment of HR+ positive metastasis breast cancer (MBC). Methods: In this real world study, we retrospectively analyzed the patients with HR+ HER 2 negative MBC who received fulvestrant 500mg treatment at Beijing cancer hospital during January 2015 to December 2018. Clinical benefit rate (CBR), progression free survival (PFS), overall survival (OS) and adverse events were investigated. Results: There were 306 patients enrolled, median age was 48.7(range 20-75) years, median line of fulvestrant was 2.11(range 1-6), 68.3%(209/306) patients were involved with visceral metastasis. The CBR was 68.6%, median PFS was 8.41m (95%CI: 7.079m-9.743m, range 0.89m-80.16m). Among the patients received fulvestrant at the first line, the PFS was 10.55m(95%CI:6.46m-14.64m, range 0.92m-34.3m). The median OS hasn’t been obtained. In subgroup analysis, the patients without liver metastasis(12.49m vs. 4.60m, p<0.001), small tumor burden(metastasis number 1-2 vs. 3-4 vs. >4, 12.65m vs. 7.72m vs. 3.98m respectively, p<0.001) and experience no or less line of chemotherapy(none vs. 1-2 lines vs. >2 lines, 14.06m vs. 7.79m vs. 3.52m respectively, p<0.001) for metastatic disease were obtained more benefit from fulvestrant treatment. For patients with visceral metastasis, the patients absence of liver metastasis was corelated with longer PFS 9.27m than 4.60m(p<0.001). There were 20(6.54%) adverse events occurred in 306 patients, 95%(19/20) were grade 1-2. The most common adverse event was oral ulcer, and serious adverse events were observed in 1 patients (0.33%) with pulmonary embolism. Conclusions: Fulvestrant was an effective and safe regimen in endocrine therapy for hormone receptor positive HER2 negative MBC. The patients who were in first line treatment, absence of liver metastasis and small tumor burden might be more benefit from fulvestrant. Corresponding authors: Huiping Li, huipingli2012@hotmail.com; Guohong Song, songguohong918@hotmail.com, Key laboratory of Carcinogenesis and Translational Research (Ministry of Education/Beijing), Department of Breast Oncology, Peking University Cancer Hospital & Institute, 52 Fucheng Rd, Beijing 100142, China Citation Format: Wen Lei, Huiping Li, Guohong Song, Ruyan Zhang, Ran Ran, Ying Yan. Efficacy observation of 306 patients with fulvestrant 500mg treatment in hormone-receptor positive HER2 negative metastasis breast cancer, a real world study [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-11-20.

Evidence for immortality and autonomy in animal cancer models is often not provided, which causes confusion on key issues of cancer biology.

Modern research into carcinogenesis has undergone three phases. Surgeons and pathologists started the first phase roughly 250 years ago, establishing morphological traits of tumors for pathologic diagnosis, and setting immortality and autonomy as indispensable criteria for neoplasms. A century ago, medical doctors, biologists and chemists started to enhance “experimental cancer research” by establishing many animal models of chemical-induced carcinogenesis for studies of cellular mechanisms. In this second phase, the two-hit theory and stepwise carcinogenesis of “initiation-promotion” or “initiation-promotion-progression” were established, with an illustrious finding that outgrowths induced in animals depend on the inducers, and thus are not authentically neoplastic, until late stages. The last 40 years are the third incarnation, molecular biologists have gradually dominated the carcinogenesis research fraternity and have established numerous genetically-modified animal models of carcinogenesis. However, evidence has not been provided for immortality and autonomy of the lesions from most of these models. Probably, many lesions had already been collected from animals for analyses of molecular mechanisms of “cancer” before the lesions became autonomous. We herein review the monumental work of many predecessors to reinforce that evidence for immortality and autonomy is essential for confirming a neoplastic nature. We extrapolate that immortality and autonomy are established early during sporadic human carcinogenesis, unlike the late establishment in most animal models. It is imperative to resume many forerunners' work by determining the genetic bases for initiation, promotion and progression, the genetic bases for immortality and autonomy, and which animal models are, in fact, good for identifying such genetic bases.

The 10th conference on metal toxicity and carcinogenesis: Overview and recent advances

Environmental and occupational metal exposures promote numerous diseases including cardiovascular, pulmonary and neurological disorders as well as various types of cancers. Research in metal toxicity and carcinogenesis focuses on addressing major health concerns associated with metal exposure. In October 2018, the 10th Conference on Metal Toxicity and Carcinogenesis held in Albuquerque, New Mexico, assembled scientists from across the United States to discuss current status and future directions in this unique and important field of research. Here, we summarize the on-going research and recent advances presented at this conference and provide insights on future progression and challenges of the field.

Architecture in 3D cell culture: An essential feature for in vitro toxicology

Three-dimensional cell culture has the potential to revolutionize toxicology studies by allowing human-based reproduction of essential elements of organs. Beyond the study of toxicants on the most susceptible organs such as liver, kidney, skin, lung, gastrointestinal tract, testis, heart and brain, carcinogenesis research will also greatly benefit from 3D cell culture models representing any normal tissue. No tissue function can be suitably reproduced without the appropriate tissue architecture whether mimicking acini, ducts or tubes, sheets of cells or more complex cellular organizations like hepatic cords. In this review, we illustrate the fundamental characteristics of polarity that is an essential architectural feature of organs for which different 3D cell culture models are available for toxicology studies in vitro. The value of tissue polarity for the development of more accurate carcinogenesis studies is also exemplified, and the concept of using extracellular gradients of gaseous or chemical substances produced with microfluidics in 3D cell culture is discussed. Indeed such gradients-on-a-chip might bring unprecedented information to better determine permissible exposure levels. Finally, the impact of tissue architecture, established via cell-matrix interactions, on the cell nucleus is emphasized in light of the importance in toxicology of morphological and epigenetic alterations of this organelle.

Downregulation of ABC Transporters in Non-neoplastic Tissues Confers Better Prognosis for Pancreatic and Colorectal Cancer Patients

Transport of a wide variety of substrates, including xenobiotics, is one of the main functions attributed to human ATP-binding cassette (ABC) proteins. Overexpression of ABC genes is considered to be an important mechanism facilitating the development of chemoresistance. Relationships between the expression levels of ABC genes in tumor tissues and established clinicopathological features were extensively studied previously. The current study tested our hypothesis that the expression levels of ABC genes in non-neoplastic (control) tissues also provide important information in relation to the relevant tumor progression. Expression levels of all human ABC genes (48 protein coding and one pseudogene), measured by qRT-PCR, were bioinformatically analyzed. The data originated from four independently collected cohorts covering three types of tumors - breast, colorectal and pancreatic carcinomas. ABC gene expression profiles (signatures) in non-neoplastic tissues (matched to tumor samples from three different tumor types) were characteristically clustered into three main types - those with the vast majority of the genes downregulated, upregulated or heterogeneously regulated. The clusters with mostly downregulated and upregulated genes were shown to possess significant relations to good and poor prognostic markers, respectively, in pancreatic and colorectal cancers. The present findings support the theory that the expression of ABC genes in non-neoplastic tissues can significantly contribute to tumor pathogenesis. Suggested multi-gene panels, consisting of the reduced number of ABC genes, have the potential to be implemented as new prognostic markers, which are especially urgent in pancreatic cancer. The results can also stimulate further primary research in carcinogenesis.

Reprogramming bladder cancer cells for studying cancer initiation and progression.

The induced pluripotent stem cell (iPSC) technology is the forced expression of specific transcription factors in somatic cells resulting in transformation into self-renewing, pluripotent cells which possess the ability to differentiate into any type of cells in the human body. While malignant cells could also be reprogrammed into iPSC-like cells with lower efficiency due to the genetic and epigenetic barriers in cancer cells, only a limited number of cancer cell types could be successfully reprogrammed until today. In the present study, we aimed at reprogramming two bladder cancer cell lines HTB-9 and T24 using a non-integrating Sendai virus (SeV) system. We have generated six sub-clones using distinct combinations of four factors-OCT4, SOX2, KLF4 and c-MYC-in two bladder cancer cell lines. Only a single sub-clone, T24 transduced with 4Fs, gave rise to iPSC-like cells. Bladder cancer cell-derived T24 4F cells represent unique features of pluripotent cells such as epithelial-like morphology, colony-forming ability, expression of pluripotency-associated markers and bearing the ability to differentiate in vitro. This is the first study focusing on the reprogramming susceptibility of two different bladder cancer cell lines to nuclear reprogramming. Further molecular characterisation of T24 4F cells could provide a better insight for biomarker research in bladder carcinogenesis and could offer a valuable tool for the development of novel therapeutic approaches in bladder carcinoma.

Epigenetic Tumor Response to Hypoxia: An Epimutation Pattern and a Method of Multi Targeted Epigenetic Therapy (MTET)

In most cases, cancer develops as a result of non-inheritable somatic mutations (epimutations), acquired by the individual adult cell, during the evolution of the cell, and propagated into an expanding clone of progeny of the cells by natural selection [1]. The role of microenvironment in selection for such acquired mutations, or epimutations, is a focus of scientific research in carcinogenesis [2]. Here we describe a defective DNA response to hypoxia due to epigenetic aberrancies, in cancer cellular biology [3]. We also summarize a literature review on hypoxia mediated epigenetic responses, and its role in carcinogenesis and metastasis. Further, we review a novel method of treating hypoxic solid tumors with a combination of epigenetic modifiers with both in vitro and in vivo results in human, translating to an improved prognosis and clinical outcome. We propose that this approach both independently and synergistically (with the current standard of care) can provide an improved outcome.