bromochloroacetic-acid and Carcinogenesis

Intermediate filament (IF) proteins make up the largest family of cytoskeletal proteins in metazoans, and are traditionally known for their roles in fostering structural integrity in cells and tissues. Remarkably, individual IF genes are tightly regulated in a fashion that reflects the type of tissue, its developmental and differentiation stages, and biological context. In cancer, IF proteins serve as diagnostic markers, as tumor cells partially retain their original signature expression of IF proteins. However, there are also characteristic alterations in IF gene expression and protein regulation. The use of high throughput analytics suggests that tumor-associated alterations in IF gene expression have prognostic value. Parallel research is also showing that IF proteins directly and significantly impact several key cellular properties, including proliferation, death, migration, and invasiveness, with a demonstrated impact on the development, progression, and characteristics of various tumors. In this review, we draw from recent studies focused on three IF proteins most associated with cancer (keratins, vimentin, and nestin) to highlight how several "hallmarks of cancer" described by Hanahan and Weinberg are impacted by IF proteins. The evidence already in hand establishes that IF proteins function beyond their classical roles as markers and serve as effectors of tumorigenesis.

Topics: Animals; Carcinogenesis; Gene Expression; Gene Expression Regulation, Neoplastic; Humans; Immunity, Innate; Inflammation; Intermediate Filaments; Keratins; Mice; Neoplasm Metastasis; Neovascularization, Pathologic; Nestin; Vimentin

Hepatitis C virus (HCV) infection has been known to use autophagy for its replication. However, the mechanisms by which HCV modulates autophagy remain controversial. We used HCV-Japanese fulminant hepatitis-1-infected Huh7 cells. HCV infection induced the accumulation of autophagosomes. Morphological analyses of monomeric red fluorescent protein (mRFP)-green fluorescent protein (GFP) tandem fluorescent-tagged LC3 transfection showed HCV infection impaired autophagic flux. Autophagosome-lysosome fusion assessed by transfection of mRFP- or GFP-LC3 and immunostaining of lysosomal-associated membrane protein 1 was inhibited by HCV infection. Decrease of HCV-induced endoplasmic reticulum (ER) stress by 4-phenylbutyric acid, a chemical chaperone, improved the HCV-mediated autophagic flux impairment. HCV infection-induced oxidative stress and subsequently DNA damage, but not apoptosis. Furthermore, HCV induced cytoprotective effects against the cellular stress by facilitating the formation of cytoplasmic inclusion bodies as shown by p62 expression and by modulating keratin protein expression and activated nuclear factor erythroid 2-related factor 2. HCV eradication by direct-acting antivirals improved autophagic flux, but DNA damage persisted. In conclusion, HCV-induced ER stress correlates with autophagic flux impairment. Decrease of ER stress is considered to be a promising therapeutic strategy for HCV-related chronic liver diseases. However, we should be aware that the risk of hepatocarcinogenesis remains even after HCV eradication.

Topics: Autophagy; Carcinogenesis; Cell Line; Endoplasmic Reticulum Stress; Gene Expression Regulation; Hepatitis C; Humans; Keratins; Liver; Liver Neoplasms; NF-E2-Related Factor 2

High levels of the intermediate filament protein keratin 17 (K17) are associated with poor prognoses for several human carcinomas. Studies in mouse models have shown that K17 expression is positively associated with growth, survival, and inflammation in skin and that lack of K17 delays onset of tumorigenesis. K17 occurs in the nucleus of human and mouse tumor keratinocytes where it impacts chromatin architecture, gene expression, and cell proliferation. We report here that K17 is induced following DNA damage and promotes keratinocyte survival. The presence of nuclear K17 is required at an early stage of the double-stranded break (DSB) arm of the DNA damage and repair (DDR) cascade, consistent with its ability to associate with key DDR effectors, including γ-H2A.X, 53BP1, and DNA-PKcs. Mice lacking K17 or with attenuated K17 nuclear import showed curtailed initiation in a two-step skin carcinogenesis paradigm. The impact of nuclear-localized K17 on DDR and cell survival provides a basis for the link between K17 induction and poor clinical outcomes for several human carcinomas.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Active Transport, Cell Nucleus; Animals; Carcinogenesis; Carcinoma; Cell Nucleus; Cell Survival; DNA Breaks, Double-Stranded; DNA Repair; Female; Gene Knockout Techniques; HeLa Cells; Humans; Intravital Microscopy; Keratin-17; Keratinocytes; Keratins; Male; Mice, Knockout; Neoplasms, Experimental; Time-Lapse Imaging

: TRIM29 (tripartite motif-containing protein 29) is a TRIM family protein that has been implicated in breast, colorectal, and pancreatic cancers. However, its role in stratified squamous epithelial cells and tumors has not been elucidated. Here, we investigate the expression of TRIM29 in cutaneous head and neck squamous cell carcinomas (SCC) and its functions in the tumorigenesis of such cancers. TRIM29 expression was lower in malignant SCC lesions than in adjacent normal epithelial tissue or benign tumors. Lower expression of TRIM29 was associated with higher SCC invasiveness. Primary tumors of cutaneous SCC showed aberrant hypermethylation of

Topics: Animals; Biomarkers, Tumor; Carcinogenesis; Carcinoma, Squamous Cell; Cell Line, Tumor; Cell Movement; Cell Proliferation; DNA Methylation; DNA-Binding Proteins; Gene Expression Regulation, Neoplastic; Head and Neck Neoplasms; Humans; Keratinocytes; Keratins; Mice; Mice, Nude; Neoplasm Invasiveness; Neoplasm Metastasis; Neoplasm Transplantation; Prognosis; Proteins; RNA, Small Interfering; Transcription Factors

To efficiently replicate the biology and pathogenesis of human esophageal adenocarcinoma (EAC) using the modified Levrat model of end-to-side esophagojejunostomy.. End-to-side esophagojejunostomy was performed on rats to induce gastroduodenoesophageal reflux to develop EAC. Animals were randomly selected and serially euthanized at 10 (n = 6), 17 (n = 8), 24 (n = 9), 31 (n = 6), 38 (n = 6), and 40 (n = 6) wk postoperatively. The esophagi were harvested for downstream histopathology and gene expression. Histological evaluation was completed to determine respective rates of carcinogenic development. Quantitative reverse transcription-polymerase chain reaction was performed to determine gene expression levels of. The overall study mortality was 15%. Causes of mortality included anastomotic leak, gastrointestinal hemorrhage, stomach ulcer perforation, respiratory infection secondary to aspiration, and obstruction due to tumor or late anastomotic stricture. 10 wk following surgery, 100% of animals presented with esophagitis. Barrett's esophagus (BE) was first observed at 10 wk, and was present in 100% of animals by 17 wk. Dysplasia was confirmed in 87.5% of animals at 17 wk, and increased to 100% by 31 wk. EAC was first observed in 44.4% of animals at 24 wk and increased to 100% by 40 wk. In addition, two animals at 38-40 wk post-surgery had confirmed macro-metastases in the lung/liver and small intestine, respectively.. Esophagojejunostomy was successfully replicated in rats with low mortality and a high tumor burden, which may facilitate broader adoption to study EAC development, progression, and therapeutics.

Topics: Adenocarcinoma; Anastomosis, Surgical; Animals; Barrett Esophagus; Biomarkers, Tumor; Carcinogenesis; Disease Models, Animal; Disease Progression; Esophageal Neoplasms; Esophagus; Gastroesophageal Reflux; Humans; Jejunum; Keratin-19; Keratins; Male; Mucin-2; Rats; Rats, Sprague-Dawley; Real-Time Polymerase Chain Reaction

Squamous cell carcinoma (SSC) of the head and neck is the sixth most common cancer and is rarely diagnosed in early stages. The transcription factor Krϋppel-like factor 4 (Klf4) suppresses cell proliferation and promotes differentiation. Inducible mice carrying an oral-specific ablation of Klf4 (K14-CreER(tam) /Klf4(flox/flox) ) develop mild dysplastic lesions and abnormal differentiation in the tongue. Aiming to analyze whether Klf4 cooperate in oral chemical carcinogenesis,we applied 4-nitroquinoline 1-oxide (4NQO), a tobacco surrogate, to this conditional Klf4 knockout mice.. K14-CreER(tam) /Klf4(flox/flox) and control mice were treated with 4NQO for 16 weeks and monitored until week 30. Histopathological samples were used for diagnostic purposes and immunofluorescence detection of epithelial differentiation markers.. 4NQO-treated K14-CreER(tam) /Klf4(flox/flox) mice (Klf4KO 4NQO) showed a significant weight loss and developed more severe dysplastic lesions than control mice with 4NQO (P < 0.005). The Klf4KO 4NQO showed a tendency to higher incidence of oral SCC and a marked keratinization pattern in dysplasias, in situ carcinomas and SCC. Also, tongues derived from Klf4KO 4NQO mice exhibited reduced terminal differentiation as judged by cytokeratin 1 staining when compared with 4NQO-treated controls.. Klf4 ablation results in more severe dysplastic lesions in oral mucosa, with a tendency to higher incidence of SCC, after chemical carcinogenesis. We show here, in a context similar to the human carcinogenesis, that absence of Klf4 accelerates carcinogenesis and correlates with the absence of cytokeratin 1 expression. These results suggest a potential role for KLF4 as a tumor suppressor gene for the tongue epithelium.

Topics: 4-Nitroquinoline-1-oxide; Animals; Carcinogenesis; Carcinogens; Carcinoma, Squamous Cell; Cell Differentiation; Disease Models, Animal; Gene Expression; Head and Neck Neoplasms; Keratins; Kruppel-Like Factor 4; Kruppel-Like Transcription Factors; Mice; Mice, Inbred C57BL; Mice, Knockout; Mouth Mucosa; Mouth Neoplasms; Precancerous Conditions; Squamous Cell Carcinoma of Head and Neck; Tongue Neoplasms

Cytokeratins (CK) are abundant in keratinized cells, particularly CK14 and CK19, which are expressed in stratified squamous epithelial cells. In this study, expression of CK14 and 19 was examined in human epithelial and dysplastic tissues. Surgical specimens from patients with clinically diagnosed oral leukoplakia or early cancer were stained with hematoxylin and eosin and classified into normal, low grade dysplasia (LGD), high grade dysplasia (HGD), or squamous cell carcinoma (SCC). The sections were examined by immunostaining and reverse transcription-polymerase chain reaction (RT-PCR) for CK14 and CK19. Expression and the results of RT-PCR for CK14 showed a decrease in the order of LGD, HGD, and SCC, whereas those of CK19 showed an increase in that order. These results suggest that decreased expression of CK14 and increased expression of CK19 serve as indicators of potential for malignant transformation.

Topics: Carcinogenesis; Carcinoma, Squamous Cell; Epithelial Cells; Humans; Keratin-14; Keratin-19; Keratins; Mouth Neoplasms

Cancer chemoprevention is defined as the use of chemicals or dietary components to block, inhibit, or reverse the development of cancer in normal or pre-neoplastic tissue. Mentha extract (ME) has antioxidant and antiperoxidant properties. This study was held to investigate the protective and anticancer effect of Mentha leaves aqueous extract on oral epithelium of mice tongues.. A total of 80 Egyptian albino mice were divided into three groups. Group I served as control (not subjected to any kind of treatment), and groups II and III were subjected to two-stage chemical carcinogenesis through topical application of dimethylbenz[a]anthracene (DMBA) followed by formaldehyde on dorsal and ventral surfaces of tongues for 9 weeks. Mentha leaves extract was administrated to group III at the same time of cancer induction. Histological changes were assessed in H&E sections at 3-week intervals. The anticarcinogenic effect of Mentha piperita was tested using immunostain with anticaspase antibody.. The oral administration of ME reduced the appearance of dysplastic cellular changes with 61% and inhibited tumor incidence with 100%. Group I showed moderate-to-strong cytoplasmic caspase expression. At 6-week interval, group II showed weak-to-moderate caspase expression, while sections from group III showed moderate-to-strong caspase expression. High significant statistical difference in the total score of caspase 3 expression was found between specimens obtained from animals sacrificed at 6 weeks in groups I, II, and III (P = 0.001**).. Our study demonstrated that Mentha piperita has inhibited the initiation and promotion of oral dysplastic lesions.

Topics: 9,10-Dimethyl-1,2-benzanthracene; Animals; Anticarcinogenic Agents; Antioxidants; Basement Membrane; Carcinogenesis; Carcinogens; Carcinoma, Squamous Cell; Caspase 3; Chemoprevention; Connective Tissue; Epithelium; Formaldehyde; Hyperplasia; Keratins; Male; Mentha piperita; Mice; Phytotherapy; Plant Extracts; Protective Agents; Tongue; Tongue Neoplasms

Receptor Activator of NF-kappa B (RANK) pathway controls mammary gland development in mice but its role in mammary stem cell fate remains undefined. We show that constitutive RANK signaling expands luminal and basal mammary compartments including mammary stem and luminal progenitor cell pools and interferes with the generation of CD61+ and Sca1+ luminal cells and Elf5 expression. Impaired mammary cell commitment upon RANK overexpression leads to the accumulation of progenitors including K14+K8+ bipotent cells and the formation of heterogeneous tumors containing hyperplastic basal, luminal, and progenitor cells. RANK expression increases in wild-type mammary epithelia with age and parity, and spontaneous preneoplastic lesions express RANK and accumulate K14+K8+ cells. In human breast tumors, high RANK expression levels are also associated with altered mammary differentiation. These results suggest that increased RANK signaling interferes with mammary cell commitment, contributing to breast carcinogenesis.

Topics: Adenocarcinoma; Aging; Animals; Breast Neoplasms; Carcinogenesis; Cell Compartmentation; Cell Differentiation; Cell Lineage; Cell Shape; Epithelium; Female; Gene Expression Regulation, Neoplastic; Humans; Keratins; Mammary Glands, Animal; Mammary Neoplasms, Experimental; Mammary Tumor Virus, Mouse; Mice; Models, Biological; Parity; Precancerous Conditions; Pregnancy; Receptor Activator of Nuclear Factor-kappa B; Stem Cells

To evaluate the expression of cytokeratin 19(CK19) and connexin 43(Cx43) in various stages of oral carcinogenesis and investigate the relationship of CK19 and Cx43 in the process of oral cancer.. 4-nitroquinoline-1-oxide(4NQO) was used to induce oral carcinogenesis in the mucosa of SD rats and immunohistoche-mical technique was used to study the expression of CK19 and Cx43 in various stages of oral carcinogenesis.. The CK19 positive staining were distributed in the basal cell layer in the normal rat lingual mucosa. While CK19 positive staining were distributed in cytoplasm of supra-basal layers in the mild dysplasia, moderate dysplasia and severe dysplasia. In oral squamous cell carcinoma(OSCC) tissue, CK19 were expressed in all the stratum of epithelium. The positive rate of CK19 in normal, mild, moderate, severe dysplasia and OSCC tissues were respectively 30.00%, 50.00%, 58.33%, 80.00%, and 91.67%. With the lesions getting worse, the positive rate and the intensity of CK19 raised significantly (P<0.05). In normal tongue mucosa, Cx43 proteins were mainly expressed in the membrane of the epithelial cells of the rat tongue. It was weakly positive in the basal cell layer, increased in the stratum spinosum and stratum granulosum, and negative in the stratum corneum. Compared with normal epithelia, the expression of Cx43 in dysplastic and OSCC epithelia decreased significantly. The positive rate of Cx43 in normal, mild, moderate, severe dysplasia and OSCC tissues were respectively 100.00%, 85.71%, 66.67%, 40.00%, and 33.33%. The expression of Cx43 was significantly decreased with severity increasing (P<0.05).. The expression of CK19 protein significantly increases with the development of rat tongue carcinoma, suggesting that CK19 is associated with carcinogenesis. The expression of Cx43 protein dramatically decrease with the development of rat tongue carcinoma, suggesting that the abnormal expression of Cx43 protein is associated with oral mucosa carcinoma origination. The expression of CK19 and Cx43 has negative correlation. Combined detection of CK19 and Cx43 has an important role in the early diagnosis of OSCC and can help to improve the sensitivity and specificity of the early diagnosis of OSCC.

Topics: 4-Nitroquinoline-1-oxide; Animals; Carcinogenesis; Carcinoma, Squamous Cell; Connexin 43; Epithelial Cells; Epithelium; Keratin-19; Keratins; Male; Mouth Mucosa; Mouth Neoplasms; Oxides; Rats; Rats, Sprague-Dawley; Tongue; Tongue Neoplasms

Keratins are structural marker proteins with tissue specific expression; however, recent reports indicate their involvement in cancer progression. Previous study from our lab revealed deregulation of many genes related to structural molecular integrity including KRT76. Here we evaluate the role of KRT76 downregulation in oral precancer and cancer development.. We evaluated KRT76 expression by qRT-PCR in normal and tumor tissues of the oral cavity. We also analyzed K76 expression by immunohistochemistry in normal, oral precancerous lesion (OPL), oral squamous cell carcinoma (OSCC) and in hamster model of oral carcinogenesis. Further, functional implication of KRT76 loss was confirmed using KRT76-knockout (KO) mice.. We observed a strong association of reduced K76 expression with increased risk of OPL and OSCC development. The buccal epithelium of DMBA treated hamsters showed a similar trend. Oral cavity of KRT76-KO mice showed preneoplastic changes in the gingivobuccal epithelium while no pathological changes were observed in KRT76 negative tissues such as tongue.. The present study demonstrates loss of KRT76 in oral carcinogenesis. The KRT76-KO mice data underlines the potential of KRT76 being an early event although this loss is not sufficient to drive the development of oral cancers. Thus, future studies to investigate the contributing role of KRT76 in light of other tumor driving events are warranted.

Topics: Adult; Animals; Carcinogenesis; Carcinoma, Squamous Cell; Cricetinae; Disease Models, Animal; Female; Gene Expression Profiling; Gene Expression Regulation, Neoplastic; Humans; Hyperplasia; Immunohistochemistry; Keratins; Male; Mice; Mice, Knockout; Middle Aged; Mouth Mucosa; Mouth Neoplasms; Neoplasm Grading; Neoplasm Staging; Prognosis; Reproducibility of Results