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Aldo Scarpa - One of the best experts on this subject based on the ideXlab platform.

  • alcohol smoking and Papillomavirus infection as risk factors for esophageal Squamous Cell Papilloma and esophageal Squamous Cell carcinoma in italy
    International Journal of Cancer, 2000
    Co-Authors: G Talamini, Paola Capelli, Giuseppe Zamboni, Marina Mastromauro, Marzia Pasetto, A Castagnini, G Angelini, Claudio Bassi, Aldo Scarpa
    Abstract:

    Esophageal Papilloma, an infrequent benign tumor, and esophageal Squamous-Cell carcinoma sometimes appear to be associated with human Papillomavirus (HPV) infection, HPV being implicated in anogenital carcinogenesis. Our aim was to assess whether there is any epidemiological difference in terms of risk factors for Papilloma and cancer. From 1989 to 1996, a total of 12,011 patients (53% male, median age 52.7 years) were submitted to esophagogastroduodenoscopy by our Digestive Endoscopy Service. The genome of HPV was sought by PCR using 2 different primer sets. Of the total, 42 subjects (0.35%), 50% male with a mean age of 45.1 years, were suffering from esophageal Squamous-Cell Papilloma and 45 (0.37%), 91% male with a mean age of 63.0 years, from esophageal Squamous-Cell carcinoma. Of these patients, only 2 with Papilloma were HPV(+). Compared with the general endoscopic population, patients with Papilloma do not present significantly different characteristics (even in terms of frequency of esophagitis and hiatal hernia). Those with carcinoma differ significantly both from the general endoscopic population and from those with Papilloma in that they are more often male (p < 0. 0001), older (p < 0.0001) and drinkers (p < 0.0001); they differ significantly only from the general population, but not from the Papilloma patients, in smoking habits. Papilloma appears to be neither a lesion involving a risk of development into a malignancy nor a marker for any such risk. Environmental factors, such as alcohol and smoking, appear to play a decisive role in esophageal carcinogenesis in northern Italy.

Abraham Nyska - One of the best experts on this subject based on the ideXlab platform.

  • Forestomach tumor induction by 2,4-hexadienal in F344N rats and B6C3F1 mice
    Archives of Toxicology, 2003
    Co-Authors: Po C Chan, Liat Lomnitski, Joel Mahler, Shyamal Peddada, Abraham Nyska
    Abstract:

    2,4-Hexadienal (2,4-Hx) was studied for its toxicity and carcinogenicity because of its α, β-unsaturated aldehyde structure and potential link between exposure to lipid peroxidation products in the diet and human malignancies. Male and female F344N rats and B6C3F1 mice received 2,4-Hx in corn oil by gavage for 16 days, 14 weeks, or 2 years. In the 16-day studies 2,4-Hx induced forestomach necrosis and ulceration at 240 mg/kg and forestomach epithelial hyperplasia at 80 mg/kg in rats and mice. In the 14-week studies the chemical induced forestomach hyperplasia and nasal olfactory atrophy or necrosis at 120 mg/kg in rats and mice. In the 2-year studies 2,4-Hx induced Squamous Cell Papilloma and carcinoma of the forestomach in male and female rats at 45 and 90 mg/kg and in male and female mice at 120 mg/kg. Two male mice in the 120 mg/kg group had uncommon Squamous Cell carcinoma of the oral cavity (tongue). Mechanistic studies indicated that the forestomach carcinogenesis in rats and mice may be due to depletion of glutathione as a result of oxidative stress induced by 2,4-Hx.

  • glutathione s transferase pi expression in forestomach carcinogenesis process induced by gavage administered 2 4 hexadienal in the f344 rat
    Archives of Toxicology, 2001
    Co-Authors: Abraham Nyska, Cindy R Moomaw, Liat Lomnitski, Po C Chan
    Abstract:

    2,4-Hexadienal (2,4-Hx), an unsaturated aldehyde formed by in vivo and in vitro peroxidation of unsaturated lipid induced, in National Toxicology Program (NTP) gavage studies of F344 rats, forestomach hyperplasia in 13-week and 2-year exposures and Squamous Papilloma and carcinoma in 2-year studies. Hyperplasia was characterized by thickening of all layers of epithelium with particularly prominent proliferation of the basal Cells. The present investigation describes the nature and potential significance of glutathione-S-transferase-Pi (GST-Pi) immunoexpression of normal forestomach epithelium, compared to that of 2,4-Hx-related basal Cell hyperplasia and Squamous Cell Papilloma and carcinoma. Paraffin-embedded forestomachs from these NTP studies were used to investigate possible correlations between the carcinogenic process and expression of GST-Pi, a physiological metabolic barrier and an inducible phase II detoxifying enzyme suggested to decrease the responsiveness of reactive oxygen species (ROS) and organic electrophilic compounds. The amount of immunopositive staining was graded on a scale of 0 (no staining) to 4 (marked staining). The simple basal epithelium of control rats showed strong immunopositivity. In cases of basal Cell hyperplasia from the 13-week and 2-year studies, these Cells usually expressed strong immunopositivity for GST-Pi (grade 3 to 4). In the 2-year treated animals only, occasional focal reduction (grade 0 to 2) in immunoreactivity for GST-Pi was noted. In Papillomas and Squamous Cell carcinomas, a wide range of GST-Pi expression was observed, perhaps indicating irregularities in its induction or change in the phenotype of these Cells compared to normal or hyperplastic ones. Reduced expression of GST-Pi by the foci of basal Cell hyperplasia and in tumor Cells may suggest changes in Cellular protection from oxidative or electrophilic DNA damage; these changes may result in genetic alterations and be the precursor to clonal expansion.

Po C Chan - One of the best experts on this subject based on the ideXlab platform.

  • Forestomach tumor induction by 2,4-hexadienal in F344N rats and B6C3F1 mice
    Archives of Toxicology, 2003
    Co-Authors: Po C Chan, Liat Lomnitski, Joel Mahler, Shyamal Peddada, Abraham Nyska
    Abstract:

    2,4-Hexadienal (2,4-Hx) was studied for its toxicity and carcinogenicity because of its α, β-unsaturated aldehyde structure and potential link between exposure to lipid peroxidation products in the diet and human malignancies. Male and female F344N rats and B6C3F1 mice received 2,4-Hx in corn oil by gavage for 16 days, 14 weeks, or 2 years. In the 16-day studies 2,4-Hx induced forestomach necrosis and ulceration at 240 mg/kg and forestomach epithelial hyperplasia at 80 mg/kg in rats and mice. In the 14-week studies the chemical induced forestomach hyperplasia and nasal olfactory atrophy or necrosis at 120 mg/kg in rats and mice. In the 2-year studies 2,4-Hx induced Squamous Cell Papilloma and carcinoma of the forestomach in male and female rats at 45 and 90 mg/kg and in male and female mice at 120 mg/kg. Two male mice in the 120 mg/kg group had uncommon Squamous Cell carcinoma of the oral cavity (tongue). Mechanistic studies indicated that the forestomach carcinogenesis in rats and mice may be due to depletion of glutathione as a result of oxidative stress induced by 2,4-Hx.

  • glutathione s transferase pi expression in forestomach carcinogenesis process induced by gavage administered 2 4 hexadienal in the f344 rat
    Archives of Toxicology, 2001
    Co-Authors: Abraham Nyska, Cindy R Moomaw, Liat Lomnitski, Po C Chan
    Abstract:

    2,4-Hexadienal (2,4-Hx), an unsaturated aldehyde formed by in vivo and in vitro peroxidation of unsaturated lipid induced, in National Toxicology Program (NTP) gavage studies of F344 rats, forestomach hyperplasia in 13-week and 2-year exposures and Squamous Papilloma and carcinoma in 2-year studies. Hyperplasia was characterized by thickening of all layers of epithelium with particularly prominent proliferation of the basal Cells. The present investigation describes the nature and potential significance of glutathione-S-transferase-Pi (GST-Pi) immunoexpression of normal forestomach epithelium, compared to that of 2,4-Hx-related basal Cell hyperplasia and Squamous Cell Papilloma and carcinoma. Paraffin-embedded forestomachs from these NTP studies were used to investigate possible correlations between the carcinogenic process and expression of GST-Pi, a physiological metabolic barrier and an inducible phase II detoxifying enzyme suggested to decrease the responsiveness of reactive oxygen species (ROS) and organic electrophilic compounds. The amount of immunopositive staining was graded on a scale of 0 (no staining) to 4 (marked staining). The simple basal epithelium of control rats showed strong immunopositivity. In cases of basal Cell hyperplasia from the 13-week and 2-year studies, these Cells usually expressed strong immunopositivity for GST-Pi (grade 3 to 4). In the 2-year treated animals only, occasional focal reduction (grade 0 to 2) in immunoreactivity for GST-Pi was noted. In Papillomas and Squamous Cell carcinomas, a wide range of GST-Pi expression was observed, perhaps indicating irregularities in its induction or change in the phenotype of these Cells compared to normal or hyperplastic ones. Reduced expression of GST-Pi by the foci of basal Cell hyperplasia and in tumor Cells may suggest changes in Cellular protection from oxidative or electrophilic DNA damage; these changes may result in genetic alterations and be the precursor to clonal expansion.

G Talamini - One of the best experts on this subject based on the ideXlab platform.

  • alcohol smoking and Papillomavirus infection as risk factors for esophageal Squamous Cell Papilloma and esophageal Squamous Cell carcinoma in italy
    International Journal of Cancer, 2000
    Co-Authors: G Talamini, Paola Capelli, Giuseppe Zamboni, Marina Mastromauro, Marzia Pasetto, A Castagnini, G Angelini, Claudio Bassi, Aldo Scarpa
    Abstract:

    Esophageal Papilloma, an infrequent benign tumor, and esophageal Squamous-Cell carcinoma sometimes appear to be associated with human Papillomavirus (HPV) infection, HPV being implicated in anogenital carcinogenesis. Our aim was to assess whether there is any epidemiological difference in terms of risk factors for Papilloma and cancer. From 1989 to 1996, a total of 12,011 patients (53% male, median age 52.7 years) were submitted to esophagogastroduodenoscopy by our Digestive Endoscopy Service. The genome of HPV was sought by PCR using 2 different primer sets. Of the total, 42 subjects (0.35%), 50% male with a mean age of 45.1 years, were suffering from esophageal Squamous-Cell Papilloma and 45 (0.37%), 91% male with a mean age of 63.0 years, from esophageal Squamous-Cell carcinoma. Of these patients, only 2 with Papilloma were HPV(+). Compared with the general endoscopic population, patients with Papilloma do not present significantly different characteristics (even in terms of frequency of esophagitis and hiatal hernia). Those with carcinoma differ significantly both from the general endoscopic population and from those with Papilloma in that they are more often male (p < 0. 0001), older (p < 0.0001) and drinkers (p < 0.0001); they differ significantly only from the general population, but not from the Papilloma patients, in smoking habits. Papilloma appears to be neither a lesion involving a risk of development into a malignancy nor a marker for any such risk. Environmental factors, such as alcohol and smoking, appear to play a decisive role in esophageal carcinogenesis in northern Italy.

Eleftherios Anagnostou - One of the best experts on this subject based on the ideXlab platform.

  • Squamous Cell Papilloma of the urinary bladder endoscopically mimicking cancer
    Case reports in pathology, 2013
    Co-Authors: Dimosthenis Miliaras, Ioannis Vakalopoulos, Eleftherios Anagnostou
    Abstract:

    Squamous Cell lesions of the urinary bladder are generally rare. Herein we describe a case of 74-year-old male patient with a benign Squamous Cell Papilloma. Histologically, the tumor presented extensive keratinization at its surface and showed no nuclear atypia or stromal invasion. The tumor Cells were negative for HPV DNA. These lesions are extremely rare, and even though they are considered benign and non-HPV related, they should be followed, since recurrence has been reported.

  • Squamous Cell Papilloma of the Urinary Bladder Endoscopically Mimicking Cancer
    2013
    Co-Authors: Dimosthenis Miliaras, Ioannis Vakalopoulos, Eleftherios Anagnostou
    Abstract:

    Copyright © 2013 Dimosthenis Miliaras et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Squamous Cell lesions of the urinary bladder are generally rare. Herein we describe a case of 74-year-old male patient with a benign Squamous Cell Papilloma. Histologically, the tumor presented extensive keratinization at its surface and showed no nuclear atypia or stromal invasion. The tumor Cells were negative for HPV DNA. These lesions are extremely rare, and even though they are considered benign and non-HPV related, they should be followed, since recurrence has been reported. 1