Annular Stenotic Oesophageal Squamous Cell Carcinoma in Cattle Exposed Naturally to Bracken Fern (Pteridium arachnoideum).

Oesophageal squamous cell carcinomas (SCCs) may be observed as exophytic masses or ulcerative or infiltrative endophytic neoplasms. However, in cattle, there is also an uncommon gross presentation as an annular stenotic thickening of the oesophageal wall. Thirteen cases of annular stenotic oesophageal SCC in cattle grazing in bracken fern (Pteridium arachnoideum) areas are reported. The lesions consisted of endophytic masses, focally extensive, firm and circumferential (annular) in the oesophageal wall. Pronounced wrinkling of the mucosa, with retracted uneven areas and subsequent luminal narrowing (stenosis), was observed in all cases. Papillomas and squamous intraepithelial lesions also were observed in these cases. The SCCs were graded as well differentiated (n = 7), moderately differentiated (n = 5) or poorly differentiated (n = 1). The neoplastic keratinocytes were surrounded by moderate to abundant fibrous connective tissue (a desmoplastic reaction), that was better demonstrated by Masson's trichrome stain. Picrosirius red-stained sections showed abundant collagen type I fibres, which contributed to the stenosing characteristics of this tumour. Although it might be easily misdiagnosed as oesophageal scar tissue, the oesophageal SCCs of cattle grazing bracken fern may have a distinctive gross appearance that should be included in the differential diagnosis of oesophageal stenosis.

Human gastric cancer, Helicobacter pylori and bracken carcinogens: A connecting hypothesis.

Long term infection of Helicobacter pylori (Hp) virulent strains is a key factor in the genesis of human gastric cancer, and so are certain dietary proinflammatory and genotoxic compounds. Carcinogenic bracken fern (Pteridium spp.) is one of these. Toxins from this plant are consumed as bracken culinary preparations, through milk and meat of bracken-exposed livestock, and drain waters from bracken swards. Bracken toxin ptaquiloside (PtQ), a suspected human carcinogen, elicits complex responses in animals leading to death. PtQ and Hp might cooperate in gastric pathologies. This paper presents an hypothesis on PtQ-Hp association leading to the enhancement of carcinogenesis in the human gastric environment that might explain the high gastric cancer incidence and death rates among Hp-infected people living in bracken zones at two levels: (1) The macroscopic scale comprising the flow of PtQ in the human diet. (2) the microscopic scale encompassing (A) gastric luminal medium; (B) gastric mucus structure and mucin degradation elicited by Hp; (C) bacterial pH gradient modification of the gastric mucosa that favors PtQ survival and its penetration into epithelial tissue; (D) combined PtQ/Hp effects on gastric immune and inflammatory responses; (E) PtQ-Hp complementary activity at selected cell signaling cascades and genome disturbance.

Intestinal adenocarcinoma in a herd of farmed Sika deer (Cervus nippon): a novel syndrome.

Intestinal adenocarcinomas were identified in 76 adult deer from a closed herd of 193 breeding animals grazing pasture heavily infested with bracken fern (Pteridium aquilinum). Tumors were observed postmortem in 32 animals with rapid weight loss, and similar neoplasms were detected in a further 44 clinically normal deer at "cull." Tumors were located in distal ileum, cecum, and proximal colon and presented as single (26%) or multiple (74%), variably sized, pale-gray, firm, poorly circumscribed neoplasms with associated intestinal strictures. Histopathologically tumors were well-differentiated, locally infiltrative, low-grade adenocarcinomas of tubular (51%), mucinous (33.5%), or mixed (15.5%) types. Extraintestinal metastases were not observed. The high incidence of intestinal adenocarcinoma within this herd suggests a specific and novel syndrome, and genetic and/or environmental factors may be involved in the pathogenesis.

TP53 intronic mutations in bovine enzootic hematuria-associated urinary bladder tumors.

Tumor protein 53 (TP53) is a tumor suppressor gene that is frequently mutated in urinary bladder tumors in both humans and animals. In cattle, urinary bladder tumors have been reported as occurring spontaneously as well as in conjunction with bracken fern consumption-induced bovine enzootic hematuria (BEH). The goal of this study was to evaluate various types of bovine urinary bladder neoplasms for the presence of TP53 alterations, using the polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP) method. DNA was extracted from both epithelial and mesenchymal urinary bladder tumor samples in cattle, associated with the chronic consumption of bracken fern. PCR was performed using primers targeted to exons 5 to 8, following electrophoresis and isolation, and the products were assessed by SSCP. Tumors in which alterations in the electrophoresis patterns were noted included hemangiomas, papillomas, and carcinomas in situ. Exemplars of these tumor types were selected for sequencing, and although no changes were noted in the 5 to 8 exon range, on either side of the designed primers for exon 6, there was some portion of intron 6 in which sequencing demonstrated a deletion of the thyamine nucleotide at position 9332. In summary, although mutations were not observed within exons 5 to 8, this represents the first report of an intronic mutation in the TP53 gene in association with bovine urinary bladder tumors. Mutations within introns can predispose tissues to the development of cancer, and therefore, a possible association between mutations of the introns of TP53 and the development of urinary bladder tumors in cattle with BEH should be further investigated.

Pteridium aquilinum and its ptaquiloside toxin induce DNA damage response in gastric epithelial cells, a link with gastric carcinogenesis.

The multifactorial origin of gastric cancer encompasses environmental factors mainly associated with diet. Pteridium aquilinum-bracken fern-is the only higher plant known to cause cancer in animals. Its carcinogenic toxin, ptaquiloside, has been identified in milk of cows and groundwater. Humans can be directly exposed by consumption of the plant, contaminated water or milk, and spore inhalation. Epidemiological studies have shown an association between bracken exposure and gastric cancer. In the present work, the genotoxicity of P. aquilinum and ptaquiloside, including DNA damaging effects and DNA damage response, was characterized in human gastric epithelial cells and in a mouse model. In vitro, the highest doses of P. aquilinum extracts (40 mg/ml) and ptaquiloside (60 µg/ml) decreased cell viability and induced apoptosis. γH2AX and P53-binding protein 1 analysis indicated induction of DNA strand breaks in treated cells. P53 level also increased after exposure, associated with ATR-Chk1 signaling pathway activation. The involvement of ptaquiloside in the DNA damage activity of P. aquilinum was confirmed by deregulation of the expression of a panel of genes related to DNA damage signaling pathways and DNA repair, in response to purified ptaquiloside. Oral administration of P. aquilinum extracts to mice increased gastric cell proliferation and led to frameshift events in intron 2 of the P53 gene. Our data demonstrate the direct DNA damaging and mutagenic effects of P. aquilinum. These results are in agreement with the carcinogenic properties attributed to this fern and its ptaquiloside toxin and support their role in promoting gastric carcinogenesis.

Immunomodulatory effects of Pteridium aquilinum on natural killer cell activity and select aspects of the cellular immune response of mice.

Pteridium aquilinum (bracken fern) is one of the most common plants. Epidemiological studies have revealed a higher risk of certain types of cancers (i.e., esophageal, gastric) in people who consume bracken fern directly (as crosiers or rhizomes) or indirectly through the consumption of milk from livestock that fed on the plant. In animals, evidence exists regarding the associations between chronic bracken fern intoxication, papilloma virus infection, and the development of carcinomas. While it is possible that some carcinogens in bracken fern could be responsible for these cancers in both humans and animals, it is equally plausible that the observed increases in cancers could be related to induction of an overall immunosuppression by the plant/its various constituents. Under the latter scenario, normal tumor surveillance responses against nascent (non-bracken-induced) cancers or responses against viral infections (specifically those linked to induction of cancers) might be adversely impacted by continuous dietary exposure to this plant. Therefore, the overall objective of this study was to evaluate the immunomodulatory effects of bracken fern following daily ingestion of its extract by a murine host over a period of 14 (or up to 30) days. In C57BL/6 mice administered (by gavage) the extract, histological analyses revealed a significant reduction in splenic white pulp area. Among a variety of immune response parameters/functions assessed in these hosts and isolated cells, both delayed-type hypersensitivity (DTH) analysis and evaluation of IFNgamma production by NK cells during T(H)1 priming were also reduced. Lastly, the innate response in these hosts-assessed by analysis of NK cell cytotoxic functionality-was also diminished. The results here clearly showed the immunosuppressive effects of P. aquilinum and that many of the functions that were modulated could contribute to the increased risk of cancer formation in exposed hosts.

Lymphoepithelioma-like carcinoma of the urinary bladder in a cow associated with bovine papillomavirus type-2.

Lymphoepithelioma-like carcinoma (LELCA) of the urinary bladder is reported in a 7-year-old cow that had grazed pasture rich in bracken fern and had suffered from severe intermittent haematuria from 3 to 4 years of age. On necropsy examination there were multiple haemorrhagic foci scattered over the mucosal surface of the urinary bladder. Microscopically there were nests, cords and sheets of neoplastic cells infiltrating the lamina propria and muscularis propria. These had a syncytial appearance with ill-defined cytoplasmic borders, large nuclei and prominent nucleoli. There was a prominent associated inflammatory infiltrate comprising lymphocytes and plasma cells with sparse histiocytes and granulocytes. Immunohistochemically, LELCA cells expressed cytokeratin but not vimentin. The LELCA was focally admixed with a concomitant papillary high-grade carcinoma that also infiltrated the lamina propria. A diffuse carcinoma in situ was also present. Bovine papillomavirus type-2 (BPV-2) DNA was amplified from frozen neoplastic tissue and from selected areas of formalin-fixed, paraffin wax-embedded tissue obtained by laser capture microdissection. Microbiological culture of a urine sample resulted in isolation of Weeksella virosa, Rhizobium radiobacter and Staphylococcus warneri. Flow cytometric analysis performed on blood mononuclear cells revealed down-regulation of a panel of markers including CD3, CD4, CD8alpha, CD45, MHC class I and MHC class II (HLA-DRalpha, HLA-DQ, HLA-DP). This report extends the spectrum of neoplastic urothelial lesions described in cattle and provides further evidence that some features of these tumours are similar to human counterparts.

Conductas y creencias de los productores rurales de los municipios Sapopema y Sao Jerónimo Da Serra, estado de Paraná, Brasil sobre las intoxicaciones crónicas por genotipos del Pteridium / Behavior and beliefs of rural producers of the municipalities of Sapopema and Sâo Jerónimo da Serra, Paraná state, Brazil on the chronic poisonings by pteridium genotypes

Fue realizada una investigación documental a 63 propietarios y gerentes de explotaciones bovinas con antecedentes de intoxicación animal por ingestión de genotipos del Pteridium de los municipios Sapopema y São Jerónimo da Serra en el estado de Paraná, Brasil, con la finalidad de conocer, evaluar y analizar las actitudes, comportamientos y nivel de conocimientos de los productores rurales en relación a los síndromes crónicos de la toxicosis y la maleza, a propósito de diseñar estrategias dirigidas a minorizar las pérdidas económicas y viabilizar la permanencia del hombre en esas áreas geográficas. El 1,6 por ciento de los animales de las fincas visitadas presentaron episodios clínicos de la toxicosis, siendo las hembras con edades de 2 a 5 años las más afectadas. De los animales clínicamente enfermos 96,1 por ciento presentaron signos de hematuria enzoótica bovina (HEB), incluso animales menores a los dos años de edad; y, 3,9 por ciento fueron identificados con síndrome digestivo anterior (SDA). El 10,3 por ciento de los productores entrevistados reconoció que regularmente ordeñan a las vacas con HEB, lo cual junto a otros factores evidenciados, se traduce en un alerta en materia de salud humana. El 61,9 por ciento de los propietarios intentan algún tipo de paliativo, en la creencia de lograr la recuperación de los animales afectados para después venderlos. Por otro lado, se determinó que no se hacen importantes reformas dirigidas al establecimiento y mejoramiento de campos de pastoreo, ni se establecen estrategias de alimentación suplementarias, pese a que la intoxicación preocupa a los propietarios rurales por sus graves consecuencias económicas, aunque declaran desconocer las repercusiones para la salud pública. Tal comportamiento obedece a razones culturales, desinformación y limitaciones financieras.

A documental research of 63 livestock owners and managers with chronic poisoning by Pteridium’ genotypes of the Municipalities of Sapopema and Sâo Jerónimo da Serra, Paraná State, Brazil, was carried out with the purpose of evaluating the attitudes, behavior and knowledge level of rural producers of the chronic toxicosis and weed syndromes, in order to design strategies focused minimizing on economical features in those geographical areas. In the farms visited, the 1.6% of the animals showed clinical sings of the losses, being females 3 to 5 years old the most affected. Of the clinically sick animals, 96.1% showed bovine enzootic hematuria (BEH) symptoms, including animals not older than 2 years old and 3.9% were identified with upper alimentary syndrome (UAS). The 10.3% of producers admitted that cows with BEH were regularly milked. This and other observed facts were a cause of growing concern in public health issues. 61.9% of the owners used various paliatives because hey have strong believes in recovering the affected animals and selling them, because they have strong believes in recovering the affected animals and selling them afterwards. On the other hand, it is clear that important reforms heading to the establishment and improvement of the pasturing fields are absent, for strategies of supplementary feeding are not being planned, although rural owners are concern about poisoning because of its serious economic consequences, effects on public health, not with standing. Such behavior obeys to cultural reasons, lack of information and financial conditions. This compromising result require the urgent intervention of the public sector to adopt educative actions that can modify in an effective way the today’s behavior and also begin an integrated program to control the problematic situation.

Pathological studies on Bovine papilloma virus-fern interaction in hamsters.

Early pathological changes of Bovine papilloma virus (BPV-2)-fern (Pteridium aquilinum and Onychium contiguum fern) interaction in hamsters were studied. In bracken-exposed cattle, BPV induces malignancy in gastrointestinal and urinary bladder mucosa. Cutaneous warts were transmitted successfully in hamsters approximately after 3 months post inoculation while urinary bladder tumour of enzootic bovine haematuria cases were not transmitted. Histologically, tumour was diagnosed as fibroma. Onychium produced more pronounced effects than bracken fern which was characterized by significant reduction in body weight and testicular atrophy. BPV-fern interaction was not appreciable during early period of tumour induction and requires long-term studies for 12 to 18 months.

Chromosome aberrations in cattle with chronic enzootic haematuria.

Chromosomal aberrations were investigated in 56 cattle with chronic enzootic haematuria (CEH) raised on pastures giving access to bracken fern. Of these animals, 27 were slaughtered and showed neoplastic lesions of the urinary bladder. Tumour tissue from 11 of the 27 cattle contained bovine papillomavirus type 2 (BPV-2) DNA. Increased numbers of chromosomal aberrations were seen in all animals with CEH, as compared with 30 control cattle that had had no access to bracken fern. The highest clastogenic effect was observed in cattle with urinary bladder cancer and evidence of BPV-2 DNA, suggesting that BPV-2 and bracken fern act synergistically in the production of chromosomal instability. In 19 of 20 animals with CEH, two bracken fern toxic compounds (quercitin and ptaquiloside) were demonstrated in urine, serum and milk.