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Background/Aim: The efficacy of melatonin and its biological significance in human bladder cancer remain poorly understood. This study aimed to investigate the functional role of melatonin in urothelial carcinogenesis. Materials and Methods: In human normal urothelial SVHUC cells with exposure to the chemical carcinogen 3-methylcholanthrene, we assessed the effects of melatonin on the neoplastic/malignant transformation. Results: In the in vitro system with carcinogen challenge, melatonin significantly prevented the neoplastic transformation of SV-HUC-1 cells. In addition, melatonin treatment resulted in increased expression of SIRT1, Rb1, and E-cadherin, and decreased expression of N-cadherin and FGFR3 in SV-HUC-1 cells. Furthermore, publicly available datasets from GSE3167 revealed that the expression of melatonin receptor 1 and melatonin receptor 2 was significantly down-regulated in bladder urothelial carcinoma tissues, compared with adjacent normal urothelial tissues. Conclusion: These findings indicate that melatonin serves as a suppressor for urothelial tumorigenesis. To the best of our knowledge, this is the first preclinical study demonstrating the impact of melatonin on the development of urothelial cancer. [ABSTRACT FROM AUTHOR]

Abstract Background The faithful maintenance of DNA methylation homeostasis indispensably requires DNA methyltransferase 1 (DNMT1) in cancer progression. We previously identified DNMT1 as a potential candidate target for oral squamous cell carcinoma (OSCC). However, how the DNMT1- associated global DNA methylation is exploited to regulate OSCC remains unclear. Methods The shRNA-specific DNMT1 knockdown was employed to target DNMT1 on oral cancer cells in vitro, as was the use of DNMT1 inhibitors. A xenografted OSCC mouse model was established to determine the effect on tumor suppression. High-throughput microarrays of DNA methylation, bulk and single-cell RNA sequencing analysis, multiplex immunohistochemistry, functional sphere formation and protein immunoblotting were utilized to explore the molecular mechanism involved. Analysis of human samples revealed associations between DNMT1 expression, global DNA methylation and collaborative molecular signaling with oral malignant transformation. Results We investigated DNMT1 expression boosted steadily during oral malignant transformation in human samples, and its inhibition considerably minimized the tumorigenicity in vitro and in a xenografted OSCC model. DNMT1 overexpression was accompanied by the accumulation of cancer-specific DNA hypomethylation during oral carcinogenesis; conversely, DNMT1 knockdown caused atypically extensive genome-wide DNA hypomethylation in cancer cells and xenografted tumors. This novel DNMT1-remodeled DNA hypomethylation pattern hampered the dual activation of PI3K-AKT and CDK2-Rb and inactivated GSK3β collaboratively. When treating OSCC mice, targeting DNMT1 achieved greater anticancer efficacy than the PI3K inhibitor, and reduced the toxicity of blood glucose changes caused by the PI3K inhibitor or combination of PI3K and CDK inhibitors as well as adverse insulin feedback. Conclusions Targeting DNMT1 remodels a novel global DNA hypomethylation pattern to facilitate anticancer efficacy and minimize potential toxic effects via balanced signaling synergia. Our study suggests DNMT1 is a crucial gatekeeper regarding OSCC destiny and treatment outcome.

Specifying the role of genetic mutations in cancer development is crucial for effective screening or targeted treatments for people with hereditary cancer predispositions. Our goal here is to find the relationship between a number of cancerogenic mutations and the probability of cancer induction over the lifetime of cancer patients. We believe that the Avrami–Dobrzyński biophysical model can be used to describe this mechanism. Therefore, clinical data from breast and ovarian cancer patients were used to validate this model of cancer induction, which is based on a purely physical concept of the phase-transition process with an analogy to the neoplastic transformation. The obtained values of model parameters established using clinical data confirm the hypothesis that the carcinogenic process strongly follows fractal dynamics. We found that the model's theoretical prediction and population clinical data slightly differed for patients with the age below 30 years old, and that might point to the existence of an ancillary protection mechanism against cancer development. Additionally, we reveal that the existing clinical data predict breast or ovarian cancers onset two years earlier for patients with BRCA1/2 mutations. [ABSTRACT FROM AUTHOR]

Specifying the role of genetic mutations in cancer development is crucial for effective screening or targeted treatments for people with hereditary cancer predispositions. Our goal here is to find the relationship between a number of cancerogenic mutations and the probability of cancer induction over the lifetime of cancer patients. We believe that the Avrami–Dobrzyński biophysical model can be used to describe this mechanism. Therefore, clinical data from breast and ovarian cancer patients were used to validate this model of cancer induction, which is based on a purely physical concept of the phase-transition process with an analogy to the neoplastic transformation. The obtained values of model parameters established using clinical data confirm the hypothesis that the carcinogenic process strongly follows fractal dynamics. We found that the model’s theoretical prediction and population clinical data slightly differed for patients with the age below 30 years old, and that might point to the existence of an ancillary protection mechanism against cancer development. Additionally, we reveal that the existing clinical data predict breast or ovarian cancers onset two years earlier for patients with BRCA1/2 mutations.

Abstract Background Intracellular Ca2+ levels can modulate several cellular functions, including proliferation and other processes found altered in neoplastic cells. Helping to maintain Ca2+ homeostasis, L-type voltage-dependent Ca2+ channels had its expression identified in neoplasias, including breast cancer. Invasive breast carcinoma of no special type, the most common classification of breast cancer, has ductal hyperplasia and ductal carcinoma in situ as its possible non-obligate precursors. This channel’s role in breast cancer development from these precursors has not been investigated. Evaluate protein expression and subcellular localization of CaV1.1, CaV1.2, and CaV1.3 in mammary epithelium without alteration and neoplastic and non-neoplastic ductal proliferative lesions through immunohistochemistry was the aim of this investigation. Methods In the present study, CaV1.1, CaV1.2, and CaV1.3 protein expression was evaluated by immunohistochemistry in breast without alteration and in proliferative non-neoplastic and neoplastic ductal epithelial lesions of the human breast. Results It was observed that CaV1.3 presented a reduction in nuclear expression at neoplastic lesions, in addition to an increase in cytoplasmic CaV1.1 expression. The analyses of membrane immunostaining showed that CaV1.2 and CaV1.3 had an increase of expression as the lesions progressed in the stages leading to invasive carcinomas. Conclusions Changes in protein expression and subcellular localization of these channels during the progression stages indicate that they may be involved in neoplastic transformation.

Free radicals define oxidative stress as the condition in which the body's antioxidant repair systems cannot keep up with the rate of cell oxidation. Oxidative stress and reactive oxygen species (free radicals) work together to damage cellular components, encourage cell neoplastic transformation, and actively affect all three stages of carcinogenesis. The most prevalent potentially cancerous conditions on the Indian subcontinent are leukoplakia and oral submucous fibrosis, which are mostly brought on by cigarette use and areca nut consumption. Assessment of 8-OHDG, SOD, and GPx levels in saliva of OPMD and OSCC patients with and without diabetes mellitus. ELISA ASSAY was used for finding the levels of 8-OHDG, SOD, and GPx. Add salivary samples and diluent 40 µL into the testing sample. Then add some 10 µL sample into the testing sample well, Cover it properly, and incubate for some 45 minutes at 37 °C. Aspirate each well and wash, repeat the process four times for a total of five washes, 1-3 minutes per time. HRP-conjugated detection antibody is added to each well. This study is one of the first attempts to find the Assessment of 8-OHDG, SOD, and GPx levels in the saliva of OPMD and OSCC patients with and without diabetes mellitus. [ABSTRACT FROM AUTHOR]

Objective To identify new human lung cancer suppressors in a genome-wide screening library during neoplastic transformation of normal human lung epithelial cells using CRISPR/Cas9-mediated genome editing, and preliminarily validate the Results in non-small cell lung cancer (NSCLC) sample databases. Methods Human normal lung epithelial BEAS-2B cell line with stable expression of Cas9 protein was constructed, and then infected with the Brunello lentiviral library encompassing 77 441 single-guide RNAs (sgRNAs) targeting 19 114 genes. Then the obtained cells were transplanted subcutaneously into nude mice. Genomic DNA of tumor cells (Tumor) and pre-transplantation cells (Input) were extracted. The extracted DNA and plasmid library were amplified for deep sequencing. By analyzing the proportion of sgRNA reads in Tumor cells compared to the Input cells and the Log Fold Change (LFC) of sgRNA reads, tumor suppressor genes that can induce oncogenic transformation of BEAS-2B cells after knockout were screened, and preliminary validation were performed using public data platforms. Results Library infections in BEAS-2B cells stably expressing Cas9 protein and subcutaneous tumorigenesis in nude mice were successfully established. Only cells infected with the library formed tumors at the inoculation sites. Sequencing Results showed that only a small part of sgRNAs were detected in tumor cells. Here, 38 genes with sgRNA reads accounting for more than 1% of the total reads or with 2 or more significantly enriched sgRNA were selected as effective candidate human lung tumor suppressor genes, including known tumor suppressor genes such as NF2 and PTEN etc, and some candidate tumor suppressor genes (AP2M1 and PSENEN) had not been previously reported in lung cancer. Enrichment analysis revealed that these candidate tumor suppressor genes were enriched in key biological pathways involved in cancer, such as Notch and Hippo signaling pathways. It is confirmed in the clinical NSCLC sample databases that 38 candidate tumor suppressor genes were mutated in NSCLC samples. Among the 17 genes with mutation rates greater than 2%, 14 genes were co-mutated with KRAS or TP53, and 3 ones were associated with the prognosis of NSCLC patients. There were 30 candidate genes with their expression in the samples of NSCLC different from those in para-tumor normal tissues, and the expression of 17 candidate genes were correlated with the prognosis of NSCLC patients. Conclusion By using an in vivo genome-wide CRISPR/Cas9 screening library, 38 human lung cancer candidate suppressor genes are identified and preliminarily verified in the clinical NSCLC sample databases.

Organoid modeling is a powerful, robust and efficient technology faithfully preserving physiological and pathological characteristics of tissues of origin. Recently, substantial advances have been made in applying genetically engineered organoid models to study early tumorigenesis and premalignant biology. These efforts promise to identify novel avenues for early cancer detection, intervention and prevention. Here, we highlight significant advancements in the functional characterization of early genomic and epigenomic events during neoplastic evolution using organoid modeling, discuss the application of the lineage-tracing methodology in organoids to study cancer cells-of-origin, and review future opportunities for further development and improvement of organoid modeling of cancer precursors.

Background/aim: The efficacy of melatonin and its biological significance in human bladder cancer remain poorly understood. This study aimed to investigate the functional role of melatonin in urothelial carcinogenesis., Materials and Methods: In human normal urothelial SVHUC cells with exposure to the chemical carcinogen 3-methylcholanthrene, we assessed the effects of melatonin on the neoplastic/malignant transformation., Results: In the in vitro system with carcinogen challenge, melatonin significantly prevented the neoplastic transformation of SV-HUC-1 cells. In addition, melatonin treatment resulted in increased expression of SIRT1, Rb1, and E-cadherin, and decreased expression of N-cadherin and FGFR3 in SV-HUC-1 cells. Furthermore, publicly available datasets from GSE3167 revealed that the expression of melatonin receptor 1 and melatonin receptor 2 was significantly down-regulated in bladder urothelial carcinoma tissues, compared with adjacent normal urothelial tissues., Conclusion: These findings indicate that melatonin serves as a suppressor for urothelial tumorigenesis. To the best of our knowledge, this is the first preclinical study demonstrating the impact of melatonin on the development of urothelial cancer., (Copyright © 2024, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.)

The cytoplasmic actin isoforms (β- and γ-actins) contribute greatly to cellular processes such as cel-cell and cell-matrix interactions, as well as cell polarization, motility and division. Distinct isoforms modulations are linked to serious pathologies, so investigations of underlying mechanisms would be of major relevance not only for fundamental research but also for clinical applications. Therefore, the study of the relevant mechanisms of change in the isoform’s balance is important for basic research and for clinical studies. The disruption of actin cytoskeleton and intercellular adhesions contribute to the neoplastic transformation, as it is important for the tumor growth, invasiveness and metastasis. Cytoplasmic actins display the functional diversity: β-actin is responsible for contractility, whereas γ-actin participates in the submembrane flexible cortex organization and direction cell motility. The involvement of β- and γ-actin in cell architecture, motility, division, and adhesion junctions in normal cells is not equivalent, and the major question was following: whether isoform ratio and the distribution in the cell corresponds to pathological function. Significant data were obtained in the study of tumor and normal cells in culture, as well as on clinical material of human tissues, and via selective regulation of β- and γ-actin’s expression. Investigation of the actins’ diversity and function in cancers may help to choose the benefit treatment strategies, and to design new therapies.

The present review contains data on microtubular protein ßIII-tubulin (TUBB3): its structure, functions, role in tumor progression, expression in normal cells and in neural and epithelial tumors of different origins. Basic working principles of microtubular system and links between TUBB3 and related β-tubulins are also briefly reviewed. We analyzed the clinical potential of TUBB3 as prognostic marker of tumor aggressiveness and drug-resistance and suggested that locally disseminated tumor cells might be found by comparison of TUBB3 expression in normal and tumor tissue of each patient. Finally, we conclude that screening for TUBB3 and other tumor markers in morphologically normal tissue adjacent to the tumor is essential for accurate diagnostics.

Adenomatoid Odontogenic Tumour (AOT) is a relatively uncommon benign odontogenic tumour composed of odontogenic epithelium in a variety of histoarchitectural patterns. Conventional AOT is predominantly seen in females in second decade of life exhibiting predilection for anterior region of maxilla. Very few cases of AOT associated with dentigerous cyst have been reported till date. The present case is unique associated with an impacted lower first premolar in the front region of the mandible of an 18-year-old female patient. The patient reported to the institute with gradually increasing swelling. The orthopantomogram revealed a unilocular radiolucency with displaced premolar. Histopathological examination confirmed 4×2.5×2 cm lesion in dimension, brownish black in colour, firm in consistency with a smooth surface grossly while cut surface revealed a cystic lumen with an impacted premolar embedded into the lining, cystic wall being nodular. Microscopic evaluation revealed a well encapsulated lesion with a thin 2-3 cell layered non keratinised stratified epithelial lining in patterns such as nests, rosette like structures and duct like structures. Thus the diagnosis of AOT arising from dentigerous cyst was confirmed. Patient's six month follow-up was uneventful. Literature search of similar cases with the review of hypothesised aetiopathogenesis is discussed in brief. The available data can help researchers resolve the uncertainty whether the AOT derived from dentigerous cyst could represent a distinct hybrid variety.

Gene knockout of the master regulator of mitochondrial fission, Drp1, prevents neoplastic transformation. Also, mitochondrial fission and its opposing process of mitochondrial fusion are emerging as crucial regulators of stemness. Intriguingly, stem/progenitor cells maintaining repressed mitochondrial fission are primed for self-renewal and proliferation. Using our newly derived carcinogen transformed human cell model, we demonstrate that fine-tuned Drp1 repression primes a slow cycling ‘stem/progenitor-like state’, which is characterized by small networks of fused mitochondria and a gene-expression profile with elevated functional stem/progenitor markers (Krt15, Sox2 etc) and their regulators (Cyclin E). Fine tuning Drp1 protein by reducing its activating phosphorylation sustains the neoplastic stem/progenitor cell markers. Whereas, fine-tuned reduction of Drp1 protein maintains the characteristic mitochondrial shape and gene-expression of the primed ‘stem/progenitor-like state’ to accelerate neoplastic transformation, and more complete reduction of Drp1 protein prevents it. Therefore, our data highlights a ‘goldilocks’ level of Drp1 repression supporting stem/progenitor state dependent neoplastic transformation.

We investigated the functional role of ATF2, a transcription factor normally activated via its phosphorylation in response to phospho-ERK/MAPK signals, in the outgrowth of urothelial cancer. In both neoplastic and non-neoplastic urothelial cells, the expression levels of androgen receptor (AR) correlated with those of phospho-ATF2. Dihydrotestosterone treatment in AR-positive bladder cancer cells also induced the expression of phospho-ATF2 and phospho-ERK as well as nuclear translocation and transcriptional activity of ATF2. Meanwhile, ATF2 knockdown via shRNA resulted in significant decreases in cell viability, migration and invasion of AR-positive bladder cancer lines, but not AR-negative lines, as well as significant increases and decreases in apoptosis or G0/G1 cell cycle phase and S or G2/M phase, respectively. Additionally, the growth of AR-positive tumors expressing ATF2-shRNA in xenograft-bearing mice was retarded, compared with that of control tumors. ATF2 knockdown also resulted in significant inhibition of neoplastic transformation induced by a chemical carcinogen 3-methylcholanthrene, as well as the expression of Bcl-2/cyclin-A2/cyclin-D1/JUN/MMP-2, in immortalized human normal urothelial SVHUC cells stably expressing AR, but not AR-negative SVHUC cells. Finally, immunohistochemistry in surgical specimens demonstrated significant elevation of ATF2/phospho-ATF2/phospho-ERK expression in bladder tumors, compared with non-neoplastic urothelial tissues. Multivariate analysis further showed that moderate/strong ATF2 expression and phospho-ATF2 positivity were independent predictors for recurrence of low-grade tumors (hazard ratio (HR) = 2.956, P = 0.045) and cancer-specific mortality of muscle-invasive tumors (HR = 5.317, P = 0.012), respectively. Thus, ATF2 appears to be activated in urothelial cells through the AR pathway and promotes the development and progression of urothelial cancer.

DNA damage repair response is an important biological process involved in maintaining the fidelity of the genome in eukaryotes and prokaryotes. Several proteins that play a key role in this process have been identified. Alterations in these key proteins have been linked to different diseases including cancer. BLM is a 3′−5′ ATP-dependent RecQ DNA helicase that is one of the most essential genome stabilizers involved in the regulation of DNA replication, recombination, and both homologous and non-homologous pathways of double-strand break repair. BLM structure and functions are known to be conserved across many species like yeast, Drosophila, mouse, and human. Genetic mutations in the BLM gene cause a rare, autosomal recessive disorder, Bloom syndrome (BS). BS is a monogenic disease characterized by genomic instability, premature aging, predisposition to cancer, immunodeficiency, and pulmonary diseases. Hence, these characteristics point toward BLM being a tumor suppressor. However, in addition to mutations, BLM gene undergoes various types of alterations including increase in the copy number, transcript, and protein levels in multiple types of cancers. These results, along with the fact that the lack of wild-type BLM in these cancers has been associated with increased sensitivity to chemotherapeutic drugs, indicate that BLM also has a pro-oncogenic function. While a plethora of studies have reported the effect of BLM gene mutations in various model organisms, there is a dearth in the studies undertaken to investigate the effect of its oncogenic alterations. We propose to rationalize and integrate the dual functions of BLM both as a tumor suppressor and maybe as a proto-oncogene, and enlist the plausible mechanisms of its deregulation in cancers.

DNA damage repair response is an important biological process involved in maintaining the fidelity of the genome in eukaryotes and prokaryotes. Several proteins that play a key role in this process have been identified. Alterations in these key proteins have been linked to different diseases including cancer. BLM is a 3′−5′ ATP-dependent RecQ DNA helicase that is one of the most essential genome stabilizers involved in the regulation of DNA replication, recombination, and both homologous and non-homologous pathways of double-strand break repair. BLM structure and functions are known to be conserved across many species like yeast, Drosophila , mouse, and human. Genetic mutations in the BLM gene cause a rare, autosomal recessive disorder, Bloom syndrome (BS). BS is a monogenic disease characterized by genomic instability, premature aging, predisposition to cancer, immunodeficiency, and pulmonary diseases. Hence, these characteristics point toward BLM being a tumor suppressor. However, in addition to mutations, BLM gene undergoes various types of alterations including increase in the copy number, transcript, and protein levels in multiple types of cancers. These results, along with the fact that the lack of wild-type BLM in these cancers has been associated with increased sensitivity to chemotherapeutic drugs, indicate that BLM also has a pro-oncogenic function. While a plethora of studies have reported the effect of BLM gene mutations in various model organisms, there is a dearth in the studies undertaken to investigate the effect of its oncogenic alterations. We propose to rationalize and integrate the dual functions of BLM both as a tumor suppressor and maybe as a proto-oncogene, and enlist the plausible mechanisms of its deregulation in cancers. [ABSTRACT FROM AUTHOR]

Neoplastic transformation is a rare but serious complication of Paget's disease of bone (PDB), occurring in fewer than 1% of individuals with polyostotic disease. Their prognosis is poor, with less than 50% surviving 5 years. In 2016, the genetic alteration of giant cell tumor (GCT) complicating PDB was identified as a founder germline mutation (P937R) in the ZNF687 gene. However, the study population was exclusively of Italian descent, and patients of different ethnic origins were not studied. To fill this gap, herein we performed mutation analysis of ZNF687 in a GCT in the pelvis of a 45‐year‐old black American woman with polyostotic PDB. The P937R mutation in ZNF687 was found in her tumor but, as expected, the ancestral haplotype that characterizes the Italian GCT/PDB patients was not found. Furthermore, we identified two additional Italian GCT/PDB patients with this ZNF687 mutation, now constituting a cohort of 18 GCT/PDB cases, all harboring the identical mutation. We also searched for ZNF687 mutations in a unique collection of tumor tissues derived from Italian PDB patients, including 28 osteosarcomas (OS/PDB), 8 undifferentiated sarcomas (SRC/PDB), 1 fibrosarcoma (FS/PDB), and 1 chondrosarcoma (CS/PDB). We identified the P937R mutation in one SRC/PDB and a different ZNF687 mutation (R331W) in 1 of 28 pagetic osteosarcomas. Thus, whereas GCT/PDB pathogenesis globally seems to involve the P937R mutation in ZNF687, other neoplasms associated with PDB seem to be less related to mutations in this gene. Finally, we identified the G34W mutation in the H3F3A gene in the maxillary tumor masses of two PDB patients, defining them as conventional GCT rather than GCT/PDB. Thus, combined molecular analysis of H3F3A and ZNF687 is essential to clarify the origin and diagnosis of tumors in PDB. © 2020 American Society for Bone and Mineral Research. [ABSTRACT FROM AUTHOR]

Nandrolone (Ndn) and boldenone (Bdn), the synthetic testosterone analogues with strong anabolic effects, despite being recognized as potentially carcinogenic compounds, are commonly abused by athletes and bodybuilders, which includes women, worldwide. This study tested the hypothesis that different doses of Ndn and Bdn can initiate neoplastic transformation of porcine ovarian putative stem cells (poPSCs). Immunomagnetically isolated poPSCs were expanded ex vivo in the presence of Ndn or Bdn, for 7 and 14 days. Results show that pharmacological doses of both Ndn and Bdn, already after 7 days of poPSCs culture, caused a significant increase of selected, stemness-related markers of cancer cells: CD44 and CD133. Notably, Ndn also negatively affected poPSCs growth not only by suppressing their proliferation and mitochondrial respiration but also by inducing apoptosis. This observation shows, for the first time, that chronic exposure to Ndn or Bdn represents a precondition that might enhance risk of poPSCs neoplastic transformation. These studies carried out to accomplish detailed molecular characterization of the ex vivo expanded poPSCs and their potentially cancerous derivatives (PCDs) might be helpful to determine their suitability as nuclear donor cells (NDCs) for further investigations focused on cloning by somatic cell nuclear transfer (SCNT). Such investigations might also be indispensable to estimate the capabilities of nuclear genomes inherited from poPSCs and their PCDs to be epigenetically reprogrammed (dedifferentiated) in cloned pig embryos generated by SCNT. This might open up new possibilities for biomedical research aimed at more comprehensively recognizing genetic and epigenetic mechanisms underlying not only tumorigenesis but also reversal/retardation of pro-tumorigenic intracellular events.

Adenomatoid Odontogenic Tumour (AOT) is a relatively uncommon benign odontogenic tumour composed of odontogenic epithelium in a variety of histoarchitectural patterns. Conventional AOT is predominantly seen in females in second decade of life exhibiting predilection for anterior region of maxilla. Very few cases of AOT associated with dentigerous cyst have been reported till date. The present case is unique associated with an impacted lower first premolar in the front region of the mandible of an 18-year-old female patient. The patient reported to the institute with gradually increasing swelling. The orthopantomogram revealed a unilocular radiolucency with displaced premolar. Histopathological examination confirmed 4×2.5×2 cm lesion in dimension, brownish black in colour, firm in consistency with a smooth surface grossly while cut surface revealed a cystic lumen with an impacted premolar embedded into the lining, cystic wall being nodular. Microscopic evaluation revealed a well encapsulated lesion with a thin 2-3 cell layered non keratinised stratified epithelial lining in patterns such as nests, rosette like structures and duct like structures. Thus the diagnosis of AOT arising from dentigerous cyst was confirmed. Patient's six month follow-up was uneventful. Literature search of similar cases with the review of hypothesised aetiopathogenesis is discussed in brief. The available data can help researchers resolve the uncertainty whether the AOT derived from dentigerous cyst could represent a distinct hybrid variety. [ABSTRACT FROM AUTHOR]

A single primary cilium projects from most vertebrate cells to guide cell fate decisions. A growing list of signaling molecules is found to function through cilia and control ciliogenesis, including the fibroblast growth factor receptors (FGFR). Aberrant FGFR activity produces abnormal cilia with deregulated signaling, which contributes to pathogenesis of the FGFR-mediated genetic disorders. FGFR lesions are also found in cancer, raising a possibility of cilia involvement in the neoplastic transformation and tumor progression. Here, we focus on FGFR gene fusions, and discuss the possible mechanisms by which they function as oncogenic drivers. We show that a substantial portion of the FGFR fusion partners are proteins associated with the centrosome cycle, including organization of the mitotic spindle and ciliogenesis. The functions of centrosome proteins are often lost with the gene fusion, leading to haploinsufficiency that induces cilia loss and deregulated cell division. We speculate that this complements the ectopic FGFR activity and drives the FGFR fusion cancers.

The origin and subsequent maintenance of sex and recombination are among the most elusive and controversial problems in evolutionary biology. Here, we propose a novel hypothesis, suggesting that sexual reproduction not only evolved to reduce the negative effects of the accumulation of deleterious mutations and processes associated with pathogen and/or parasite resistance but also to prevent invasion by transmissible selfish neoplastic cheater cells, henceforth referred to as transmissible cancer cells. Sexual reproduction permits systematic change of the multicellular organism's genotype and hence an enhanced detection of transmissible cancer cells by immune system. Given the omnipresence of oncogenic processes in multicellular organisms, together with the fact that transmissible cancer cells can have dramatic effects on their host fitness, our scenario suggests that the benefits of sex and concomitant recombination will be large and permanent, explaining why sexual reproduction is, despite its costs, the dominant mode of reproduction among eukaryotes. [ABSTRACT FROM AUTHOR]

Background: Second malignant neoplasm is one of the most devastating late effects of childhood cancers. This study aimed to evaluate the incidence and survival outcomes of patients developing second malignant neoplasms (SMNs) after surviving childhood cancer in Korea. Methods: Medical data of childhood cancer patients diagnosed between 1993 and 2012 were obtained from the Korea Central Cancer Registry. The risk of developing SMNs was calculated using standardized incidence ratio (SIR), excess absolute risk (EAR), and cumulative risk. Kaplan-Meier survival curves were estimated, stratified by SMN status. Results: A total of 28,405 childhood cancer patients were diagnosed in the study period, and 337 (1.2%) developed SMN. The total follow-up period was 197,359 person-years at risk (PYR), with a median follow-up duration of 5.6 years. Overall SIR was 20.0, which was 23.2 in women, and 17.6 in men. The overall EAR was 16.4 per 10,000 PYR. The most common types of SMNs, in order of incidence, were other malignant epithelial neoplasms, leukemia, and soft tissue sarcomas. The cumulative incidence of developing SMNs was 0.7% at 5 years, 1.2% at 10 years, and 2% at 15 years. After primary cancer diagnosis, the 10-year overall survival rate of patients with SMNs was 65.1%, which was lower than the 73.4% in patients without SMN. After SMN diagnosis, the 10-year overall survival rate was 55.8%. Conclusion: Through this registry-based study of 5.6 years of follow up, childhood cancer survivors were found to be at 20-fold higher risk of developing a malignant neoplasm compared to the general population. The majority of malignant neoplasms are malignant epithelial neoplasms, leukemia, and soft tissue sarcomas. Continued surveillance for assessing long-term risks, and guidance for appropriate long-term follow up of childhood cancer survivors, are needed. [ABSTRACT FROM AUTHOR]

Among the major mechanisms involved in tumorigenesis, DNA methylation is an important epigenetic modification impacting both genomic stability and gene expression. Methylation of promoter-proximal CpG islands (CGIs) and transcriptional silencing of tumor suppressors represent the best characterized epigenetic changes in neoplastic cells. The global cancer-associated effects of DNA hypomethylation influence chromatin architecture and reactivation of repetitive elements. Moreover, recent analyses of cancer cell methylomes highlight the role of the DNA hypomethylation of super-enhancer regions critically controlling the expression of key oncogenic players. We will first summarize some basic aspects of DNA methylation in tumorigenesis, along with the role of dysregulated DNA methyltransferases and TET (Ten-Eleven Translocation)-family methylcytosine dioxygenases. We will then examine the potential contribution of epimutations to causality and heritability of cancer. By reviewing some representative genes subjected to hypermethylation-mediated silencing, we will survey their oncosuppressor functions and roles as biomarkers in various types of cancer. Epithelial-to-mesenchymal transition (EMT) and the gain of stem-like properties are critically involved in cancer cell dissemination, metastasis, and therapeutic resistance. However, the driver vs passenger roles of epigenetic changes, such as DNA methylation in EMT, are still poorly understood. Therefore, we will focus our attention on several aspects of DNA methylation in control of EMT and metastasis suppressors, including both protein-coding and noncoding genes.

Background: The grading of oral epithelial dysplasia is not possible in the atrophic epithelium of oral submucous fibrosis (OSMF). Recently, we found that features such as increased basal cell layer hyperplasia, abnormal superficial mitosis, increased nuclear-cytoplasmic ratio, increased nuclear size, and hyperchromasia represent transformation-relevant dysplastic features in the atrophic epithelium of OSMF. The presence of these features can be considered a high-risk feature for patients. However, these findings have not been tested and authenticated using markers relevant to oral carcinogenesis. Method: Paraffin-embedded tissues from 30 normal oral mucosa (NOM) and 50 OSMF were retrieved from 2008 to 2016 and subjected to immunohistochemical expression using Ki67, CD105 and α-SMA antibodies. Results: Ki67 LI showed significant increases from NOM (12.47±2.34) to LRED (23.47±3.75) to HRED (34.31±7.31) (<0.0001). Similarly, MVD was increased significantly from NOM (3.53±5.17) to LRED (27.57±12.25) to HRED (46.18±12.55) (p<0.0001). The expression of α-SMA was significantly increased from LRED (0.21±0.41) to HRED (1.13±0.56) (<0.0001). The Ki67 LI and α-SMA; MVD and α-SMA; and Ki67Ki67 LI and MVD in NOM, LRED and HRED showed a statistically significant positive correlation (P<0.0001). The increase in Ki67 LI was directly proportional to MVD and α-SMA expression from NOM to LRED to HRED (P<0.0001). The connective tissue stroma of NOM lacks α-SMA expression. Mild myofibroblast expression was noted in 4 cases of LRED (14.28%) and in 18 cases of HRED (81.81%). Moderate expression was noted only in 4 cases of HRED (22.22%). Conclusion: Ki67 LI, CD105, and α-SMA expression showed significant differences between normal, LRED and HRED. These findings further support that features such as increased basal cell layer hyperplasia, abnormal superficial mitosis, increased nuclear-cytoplasmic ratio, and hyperchromasia could be transformation-relevant dysplastic features. [ABSTRACT FROM AUTHOR]

Red ginseng oil (RGO) has been shown to possess anti-inflammatory and hepatoprotective activity. In this study, we evaluated the inhibitory effect of RGO on 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated neoplastic transformation of JB6 P+ cells. RGO pretreatment abolished the transformation of JB6 P+ cells challenged by TPA. RGO suppressed the transactivation of activator protein-1 (AP-1) and nuclear factor kappa B (NF-κB) transcription factors as well as protein levels of cyclooxygenase-2, cyclin D1, cyclin E, and Bcl-2 in the TPA-treated cells. Additionally, TPA-induced phosphorylations of extracellular signal-regulated kinases, 90 kDa ribosomal S6 kinase 2, c-Jun N-terminal kinases, and glycogen synthase kinase 3β were downregulated in the presence of RGO. Furthermore, RGO induced the nuclear factor erythroid 2-related factor 2 (Nrf2)-mediated antioxidant enzyme heme oxygenase-1 (HO-1) expression, and effectively blocked the overproduction of TPA-induced reactive oxygen species. These results suggest that RGO exerts a potent chemopreventive activity in skin cell model. [ABSTRACT FROM AUTHOR]

Dentigerous cyst (DC) is a developmental odontogenic cyst that encloses the crown of an unerupted tooth by expansion of its follicle with accumulation of fluid between the reduced enamel epithelium and the tooth crown and is attached to the neck of the tooth. The lining of DCs shows a potential for neoplastic transformation to ameloblastoma, squamous cell carcinoma, and mucoepidermoid carcinoma. Here, we report a rare case of an ameloblastoma arising in the wall of a DC. [ABSTRACT FROM AUTHOR]