Squamous papilloma of the proximal oesophagus associated with an inlet patch: a potential aetiological relationship

Squamous papillomas are rare benign lesions that can be found in the oesophagus. It has been theorised that irritation of the esophageal mucosa leads to squamous papilloma formation. There is evidence to suggest that squamous papillomas of the distal oesophagus are related to irritation due to reflux of gastric acid. In this case report, we describe for the first time a squamous papilloma of the upper oesophagus located just distal to an inlet patch. Inlet patches consist of gastric mucosa located in the proximal oesophagus. They are capable of producing acid. This case raises the possibility that just as squamous papillomas of the distal oesophagus may be related to acid exposure from the reflux of gastric acid, squamous papillomas of the proximal oesophagus may be related to acid exposure from the locally-produced acid of inlet patches.

Systemic bevacizumab as adjuvant therapy for recurrent respiratory papillomatosis in children: A series of three pediatric cases and literature review

Recurrent respiratory papillomatosis (RRP), a viral disease caused by human papillomavirus (HPV), is the most common benign neoplasm of the larynx among children and the second most frequent cause of infantile hoarseness. The course of the disease is variable; some patients experience spontaneous remission, while others may develop an aggressive respiratory compromise. Especially juvenile-onset RRP cases experience shorter intervals between surgical interventions and thus more surgeries overall, causing high rates of depression and voice-related quality of life. Various local adjuvant therapies have been studied with mixed efficacy and some early potential but have failed to show consistent effect across large cohorts of patients. Bevacizumab, a recombinant monoclonal antibody that inhibits VEGF, has shown efficacy in patients with rapid regrowth of papillomas with severe airway compromise, and/or distal multisite spread of disease. We present three juvenile-onset RRP cases successfully managed with systemically administered bevacizumab.

Environmental DNA monitoring of oncogenic viral shedding and genomic profiling of sea turtle fibropapillomatosis reveals unusual viral dynamics

Pathogen-induced cancers account for 15% of human tumors and are a growing concern for endangered wildlife. Fibropapillomatosis is an expanding virally and environmentally co-induced sea turtle tumor epizootic. Chelonid herpesvirus 5 (ChHV5) is implicated as a causative virus, but its transmission method and specific role in oncogenesis and progression is unclear. We applied environmental (e)DNA-based viral monitoring to assess viral shedding as a direct means of transmission, and the relationship between tumor burden, surgical resection and ChHV5 shedding. To elucidate the abundance and transcriptional status of ChHV5 across early, established, regrowth and internal tumors we conducted genomics and transcriptomics. We determined that ChHV5 is shed into the water column, representing a likely transmission route, and revealed novel temporal shedding dynamics and tumor burden correlations. ChHV5 was more abundant in the water column than in marine leeches. We also revealed that ChHV5 is latent in fibropapillomatosis, including early stage, regrowth and internal tumors; higher viral transcription is not indicative of poor patient outcome, and high ChHV5 loads predominantly arise from latent virus. These results expand our knowledge of the cellular and shedding dynamics of ChHV5 and can provide insights into temporal transmission dynamics and viral oncogenesis not readily investigable in tumors of terrestrial species.

Gingival Papillomatosis as the Oral Sign of Cowden Syndrome: A Case Report

Cowden syndrome (CS) is a rare autosomal dominant, hereditary, multiorgan disease with higher risk for malignancies (breast, thyroid, endometrium). Mucocutaneous lesions occur in 90% of cases and are characterized by facial trichilemmomas, oral mucosal papillomas, and benign acral keratoses. We present the case of a 39-year-old female patient with the chief complaint of "white spots" on the upper and lower attached gingiva accompanied with skin changes on the face, hands, and soles. The patient's family medical history revealed that her mother had an endometrial polyp and the sister had thyroid cancer. In the patient's medical personal history she reported follicular thyroid adenoma, thyroid abnormalities (i.e. lymphocytic thyroiditis), fibrocystic changes and juvenile breast papillomatosis, lipoma, multiple fibromas, and genitourinary tumors. Based on extensive family and personal medical history, physical examination and histopathological findings, diagnostic criteria were fulfilled for the diagnosis of Cowden syndrome.

Florid cutaneous papillomatosis as a marker of neoplastic recurrence

Florid cutaneous papillomatosis is a rare paraneoplastic dermatosis, most commonly associated with gastric adenocarcinoma. It is characterized by a sudden onset of hyperkeratotic papules, clinically indistinguishable from viral warts. We report an 80-year-old man who presented to our department with a two-month history of multiple verrucous lesions affecting the face, perioral region, and hands. Two years before, he was treated for a gastric adenocarcinoma with a subtotal gastrectomy, but showed no evidence of residual disease or recurrence. Given the clinical background, a diagnosis of florid cutaneous papillomatosis was considered. Skin biopsy excluded a viral origin, and tumour recurrence was later identified through an abdominal ultrasound. The onset of this entity is typically prior or concurrent with the diagnosis of the internal malignancy, but it may also represent the first sign of recurrence of a previously treated neoplasm. Its early recognition is essential to ensure a thorough investigation and prompt treatment.

Elevated HuR in Pancreas Promotes a Pancreatitis-Like Inflammatory Microenvironment That Facilitates Tumor Development

Human antigen R (ELAVL1; HuR) is perhaps the best-characterized RNA-binding protein. Through its overexpression in various tumor types, HuR promotes posttranscriptional regulation of target genes in multiple core signaling pathways associated with tumor progression. The role of HuR overexpression in pancreatic tumorigenesis is unknown and led us to explore the consequences of HuR overexpression using a novel transgenic mouse model that has a >2-fold elevation of pancreatic HuR expression. Histologically, HuR-overexpressing pancreas displays a fibroinflammatory response and other pathological features characteristic of chronic pancreatitis. This pathology is reflected in changes in the pancreatic gene expression profile due, in part, to genes whose expression changes as a consequence of direct binding of their respective mRNAs to HuR. Older mice develop pancreatic steatosis and severe glucose intolerance. Elevated HuR cooperated with mutant K-rasG12D to result in a 3.4-fold increase in pancreatic ductal adenocarcinoma (PDAC) incidence compared to PDAC presence in K-rasG12D alone. These findings implicate HuR as a facilitator of pancreatic tumorigenesis, especially in the setting of inflammation, and a novel therapeutic target for pancreatitis treatment.

[Establishment of a SD rat model of vulvar lichen simplex chronicus and detection of the expression of protease activated receptor 2]

OBJECTIVE

To establish a SD rat model of vulvar lichen simplex chronicus (LSC) and investigate the expression of protease activated receptor 2 (PAR2) in the genital skin.

METHODS

Seventy female SD rats were randomly divided into group A (blank control group, n=10), group B (with application of acetone solution 3 times per week for 10 weeks, n=10), group C (with chronic mechanical irritation 3 times per week for 10 weeks, n=10), and group D (with topical treatment with 0.5= 7,12-Dimethylbenzanthracene [DMBA] in acetone solution and chronic mechanical irritation 3 times per week for 10 weeks, n=40). The changes of the genital skin changes were observed regularly and the expression of PAR2 in groups A and D was detected with immunohistochemistry, Western blotting and qRT-PCR.

RESULTS

In group D, LSC occurred in 23 rats (57.5=) at 8 weeks and in 38 rats (95=) at 10 weeks; 8 rats (20=) showed papilloma at 12 weeks. Acetone treatment or chronic mechanical irritation did not cause LSC in the rats. Immunohistochemistry, Western blotting and qRT-PCR showed significantly increased expressions of PAR2 in group D at both the protein and mRNA levels as compared with those in group A (P<0.05).

CONCLUSION

0.5= DMBA in acetone solution along with chronic mechanical irritation can induce LSC in female SD rats, and PAR2 is closely related with the occurrence and progression of LSC.

Preliminary Report Of Endolaryngeal And Endotracheal Laser Surgery Of Juvenile-Onset Recurrent Respiratory Papillomatosis By Nd:Yag Laser and a New Fiber Guidance Instrument

OBJECTIVES: Recurrent respiratory papillomatosis (RRP) caused by human papilloma virus (type 6 and 11) is the most common benign neoplasm of the larynx in children. Despite being a benign disease, treatment is very difficult and is characterized by frequent recurrence, spread throughout the respiratory tract, and malignant degeneration. Besides surgical resection and the established CO2 laser treatment, laser surgery by fiber-guided Nd:YAG laser light promises to be a bloodless and effective treatment procedure. To improve this new method, a novel fiber guidance instrument has been developed to aid in endolaryneal laser surgery of RRP.

STUDY DESIGN AND SETTING: The method described uses a specially designed instrument for fiber guidance that is equipped with a bendable distal tip to move the fiber end precisely. Moreover, the instrument includes an additional channel for the suction of smoke and pyrolysis products. Up to now, 5 patients (aged 4 to 8 years) with RRP were treated by Nd:YAG laser light (λ = 1064 nm; power, 10W; irradiance, 3.5 kW/cm 2 , continuous wave) with a prototype version of the new instrument and were followed up for 12 months each. RESULTS: Because of the adequate length and the bendable distal tip with a range of −5° up to 45° to the optical axis of the fiber and less than 10% light loss at maximal deflection, RRP can be treated by Nd:YAG laser light easily and precisely. The continuous suctioning ensured an optimum view of the operating field and a minimal load of potential infectious laser plume and toxic pyrolysis products for the patient as well as for the physician. The laser treatment of RRP with the new fiber guidance instrument was only minimally traumatic. During 1-year follow-up visits, all Nd:YAG laser light-treated patients, showed a regression of the disease.

CONCLUSIONS: The new fiber guidance instrument enables a precise and easy treatment of the RRP with fiber-guided laser systems (eg, Nd:YAG-, diode-, and KTP-lasers) and an effective removal of infectious laser plume as well as toxic pyrolysis products. A follow-up period of 1 year revealed that Nd:YAG laser surgery seems to prevent a rapid recurrence of juvenile respiratory papillomatosis in the treated patients.

Metal contamination as a possible etiology of fibropapillomatosis in juvenile female green sea turtles Chelonia mydas from the southern Atlantic Ocean

Environmental contaminants have been suggested as a possible cause of fibropapillomatosis (FP) in green sea turtles. In turn, a reduced concentration of serum cholesterol has been indicated as a reliable biomarker of malignancy in vertebrates, including marine turtles. In the present study, metal (Ag, Cd, Cu, Fe, Ni, Pb and Zn) concentrations, oxidative stress parameters [antioxidant capacity against peroxyl radicals (ACAP), protein carbonyls (PC), lipid peroxidation (LPO), frequency of micronucleated cells (FMC)], water content, cholesterol concentration and 3-hydroxy-3-methylglutaryl-CoA reductase (HMGR) activity were analyzed in the blood/serum of juvenile (29.3-59.5cm) female green sea turtles (Chelonia mydas) with FP (n=14) and without FP (n=13) sampled at Ubatuba coast (São Paulo State, southeastern Brazil). Green sea turtles were grouped and analyzed according to the severity of tumors. Individuals heavily afflicted with FP showed significantly higher blood Cu, Pb and Fe concentrations, blood LPO levels, as well as significantly lower serum cholesterol concentrations and HMGR activity than turtles without FP. Significant and positive correlations were observed between HMGR activity and cholesterol concentrations, as well as LPO levels and Fe and Pb concentrations. In turn, Cu and Pb concentrations were significantly and negatively correlated with HMGR activity and cholesterol concentration. Furthermore, Cu, Fe and Pb were positively correlated with each other. Therefore, the reduced concentration of serum cholesterol observed in green sea turtles heavily afflicted with FP is related to a Cu- and Pb-induced inhibition of HMGR activity paralleled by a higher LPO rate induced by increased Fe and Pb concentrations. As oxidative stress is implicated in the pathogenesis of viral infections, our findings support the idea that metal contamination, especially by Cu, Fe and Pb, may be implicated in the etiology of FP in green sea turtles through oxidative stress generation.

Three paraneoplastic signs in the same patient with gastric adenocarcinoma

This is the report of a 76-year-old male with typical lesions of acanthosis nigricans maligna (ANM), florid cutaneous papillomatosis (FCP), and tripe palms (TP) for 2 years. He did not have any gastrointestinal complaints. Pathologic findings of skin supported the diagnosis of ANM. Because gastric adenocarcinoma is the most common neoplasm associated with these paraneoplastic dermatoses, further tests were carried out. Endoscopic examination was performed and an adenocarcinoma of the esophagogastric junction was confirmed. Meanwhile, multiple small polyps in the middle and the lower thirds of the esophagus were observed. The patient was referred for further evaluation and subsequent surgical resection of the tumor.Acanthosis nigricans (AN) is a hyperkeratotic mucocutaneous eruption of heterogenous etiology, which is characterized by hyperpigmentation, velvety cutaneous thickening, intensified skin markings, and development of verrucous excrescences typically involving the intertriginous areas. AN is classified into benign and malignant forms on the basis of clinical associations. Malignant acanthosis nigricans (MAN) tends to be extensive and involves mucosal surfaces, mostly in elderly people. Florid cutaneous papillomatosis (FCP), also known as the Schwartz-Burgess syndrome, is characterized by the rapid appearance of multiple verrucous lesions that are clinically indistinguishable from common warts [1]. Tripe palms (TP) is characterized by diffuse, yellowish palmar hyperkeratosis, with enhancement of the epidermal ridges on the hands (dermatoglyphics), resembling intestinal villosities [1]. The association of these three paraneoplastic dermatoses (FCP, ANM and TP) in the same patient has been reported. Herein, we report an elderly male with three paraneoplastic dermatoses for two years. On the initial presentation, he did not report any systemic complaints; diagnostic tests confirmed the presence of a gastric adenocarcinoma.

Heterogeneity of gene expression in murine squamous cell carcinoma development-the same tumor by different means

Transformation is a complex process, involving many changes in the cell. In this work, we investigated the transcriptional changes that arose during the development of squamous cell carcinoma (SCC) in mice. Using microarray analysis, we looked at gene expression during different stages in cancer progression in 31 mice. By analyzing tumor progression in each mouse separately, we were able to define the global changes that were common to all 31 mice, as well as significant changes that occurred in fewer individuals. We found that different genes can contribute to the tumorigenic process in different mice, and that there are many ways to acquire the malignant properties defined by Hanahan and Weinberg as "hallmarks of cancer". Eventually, however, all these changes lead to a very similar cancerous phenotype. The finding that gene expression is strongly heterogeneous in tumors that were induced by a standardized protocol in closely related mice underscores the need for molecular characterization of human tumors and personalized therapy.

Decreased incidence of papillomas in mice with impaired EGFR function during multi-stage skin carcinogenesis

Genetically modified mouse lines revealed that the epidermal growth factor receptor (EGFR) is essential for the development and homoeostasis of the epidermis and hair follicles. However, more detailed studies have been precluded by the shortened lifespan of Egfr knockout mice. We employed the mouse line Wa5 (carrying a point mutation resulting in the expression of a dominant negative receptor) to analyse the impact of significantly reduced EGFR signalling during multi-stage chemical skin carcinogenesis. Seven-week-old Wa5 females and control littermates received a single application of 7,12-dimethylbenz(a)anthracene followed by multiple applications of 12-O-tetradecanoylphorbol-13-acetate for 26 weeks. Wa5 mice remained free of papillomas for a longer time and developed significantly fewer tumors than control littermates. In contrast, the mean tumor size was not different between groups. The present data indicate that EGFR signalling contributes to tumor growth during multi-stage chemical carcinogenesis of the skin in mice possibly by acting as a survival factor for skin tumor cells.

Actomyosin-mediated cellular tension drives increased tissue stiffness and β-catenin activation to induce epidermal hyperplasia and tumor growth

Tumors and associated stroma manifest mechanical properties that promote cancer. Mechanosensation of tissue stiffness activates the Rho/ROCK pathway to increase actomyosin-mediated cellular tension to re-establish force equilibrium. To determine how actomyosin tension affects tissue homeostasis and tumor development, we expressed conditionally active ROCK2 in mouse skin. ROCK activation elevated tissue stiffness via increased collagen. β-catenin, a key element of mechanotranscription pathways, was stabilized by ROCK activation leading to nuclear accumulation, transcriptional activation, and consequent hyperproliferation and skin thickening. Inhibiting actomyosin contractility by blocking LIMK or myosin ATPase attenuated these responses, as did FAK inhibition. Tumor number, growth, and progression were increased by ROCK activation, while ROCK blockade was inhibitory, implicating actomyosin-mediated cellular tension and consequent collagen deposition as significant tumor promoters.

HPV-associated oral warts

Human papillomavirus (HPV) is strictly epitheliotropic, infecting stratified squamous cutaneous and mucosal epithelial cells. Oral HPV infection may be subclinical or putatively associated with benign or malignant oral neoplasms. The benign HPV-associated oral lesions, focal epithelial hyperplasia (Heck disease), oral squamous cell papilloma, oral verruca vulgaris (common wart) and oral condyloma acuminatum, are collectively referred to as oral warts. Oral warts are usually asymptomatic, may be persistent or uncommonly, may regress spontaneously. HPV-associated oral warts have a prevalence of 0.5% in the general population, occur in up to 5% of HIV-seropositive subjects, and in up to 23% of HIV-seropositive subjects on highly active antiretroviral therapy. This paper is a clinico-pathological review of HPV-associated oral warts.

IFNgamma promotes papilloma development by up-regulating Th17-associated inflammation

IFNgamma plays a crucial role in immunity against a variety of transplanted tumors and methylcholanthrene-mediated tumorigenesis in mice. However, it is not clear whether and how endogenous IFNgamma influences 7,12-dimethylbenz(a)anthracene (DMBA)-induced and 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced papilloma development. We found here that IFNgamma expression was markedly up-regulated shortly after DMBA/TPA application to the skin. Surprisingly, neutralizing IFNgamma activity in vivo did not increase but rather decreased tumor development. Furthermore, IFNgamma receptor-deficient mice were also more resistant to papilloma development than their counterparts were. IFNgamma acted mainly in the promotion stage of papilloma development by enhancing TPA-induced leukocyte infiltration and epidermal hyperproliferation. The up-regulation of tumor necrosis factor alpha, interleukin (IL)-6, and transforming growth factor beta was largely dependent on host IFNgamma responsiveness. Remarkably, up-regulation of both IL-17 expression in the skin and T helper 17 (Th17) cell number in draining lymph nodes after DMBA/TPA treatment was dependent on IFNgamma signaling. Depletion of IL-17 not only decreased the DMBA/TPA-induced inflammation and keratinocyte proliferation but also delayed papilloma development. These results show that IFNgamma, under certain conditions, may promote tumor development by enhancing a Th17-associated inflammatory reaction.

Overexpression of the cellular DEK protein promotes epithelial transformation in vitro and in vivo

High levels of expression of the human DEK gene have been correlated with numerous human malignancies. Intracellular DEK functions have been described in vitro and include DNA supercoiling, DNA replication, RNA splicing, and transcription. We have shown that DEK also suppresses cellular senescence, apoptosis, and differentiation, thus promoting cell growth and survival in monolayer and organotypic epithelial raft models. Such functions are likely to contribute to cancer, but direct evidence to implicate DEK as an oncogene has remained elusive. Here, we show that in line with an early role in tumorigenesis, murine papilloma formation in a classical chemical carcinogenesis model was reduced in DEK knockout mice. Additionally, human papillomavirus E6/E7, hRas, and DEK cooperated in the transformation of keratinocytes in soft agar and xenograft establishment, thus also implicating DEK in tumor promotion at later stages. Finally, adenoviral DEK depletion via short hairpin RNA expression resulted in cell death in human tumor cells in vitro and in vivo, but did not significantly affect differentiated epithelial cells. Taken together, our data uncover oncogenic DEK activities as postulated from its frequent up-regulation in human malignancies, and suggest that the targeted suppression of DEK may become a strategic approach to the treatment of cancer.

[Recurrent respiratory papillomatosis: update review]

This paper updates information on epidemiology, etiology, clinical features, surgical and anti-relapse treatment of recurrent respiratory papillomatosis in children.

High prevalence of thyroid nodules in patients with achrocordons (skin tags). Possible role of insulin-resistance

Due to the observation of a great number of patients having achrocordons, when they underwent fine needle biopsies for thyroid nodules, we decided to perform a prospective study to investigate the relationship between this finding and the presence of insulin resistance (IR), since achrocordons are commonly seen in hyperinsulinemic subjects. A total of 120 consecutive women, aged 18-35 yrs were studied. All subjects were also evaluated by thyroid ultrasound (US) for measuring thyroid volume and the presence of non-palpable nodules. Basal and post-prandial serum insulin was measured in all of them, as well as the Homeostasis Model Assessment (HOMA). Subjects were divided in two groups: Group A, with achrocordons (n = 44) and Group B, without achrocordons (n = 76). Group A showed 24 patients (54.5%) with thyroid nodules, whereas Group B only 13 subjects (17.1%); p = 0.0087. When we considered, as having high normal thyroid volume, the glands weighting more than 16 grams by US, without nodules, it was found that 8/44 cases from Group A (18.6%) and 3/76 from Group B (3.9%) fitted in such category, p = 0.0076. In patients with nodules and/or bigger thyroids, IR was observed in 36/44 (81.8%) of Group A and 14/76 (18.4%) of Group B, p = 0.0069, while the overall prevalence of IR was 0.47 in Group A and 0.05 in Group B, p = 0.00094. It is concluded that patients with achrocordons have a higher prevalence of US-detected thyroid nodules and larger thyroid glands. Then, it may be beneficial to search for thyroid abnormalities in those subjects with skin tags.

Identical but different: mechanism of cancer development and response to treatment for human papillomavirus-related and non-related squamous cell cancer of the head and neck

Head and neck squamous cell carcinoma (HNSCC) continues to be a significant cause of cancer worldwide. Tobacco and alcohol use are the most common risk factors for HNSCC. Over the past five years, research has identified the human papillomavirus (HPV) as a factor in the development of approximately 25 percent of HNSCC. Current research at the Sanford Cancer Research Center shows that the immune system can recognize HPV induced cellular changes, making HPV+ cancer more curable then HPV- cancer. Clinical trials are being developed that will improve cancer therapy by selectively treating sub-types of HNSCC through immunotherapy. The role of the primary care physician in the care of head and neck cancer is in the identification, referral and follow-up of these affected patients. The risk factors and signs and symptoms of head and neck cancer are discussed as well as indications for referral to a head and neck oncologist.

Friction induced skin tags

Skin tags are common benign neoplasm located predominantly in intertriginous skin. Generally of cosmetic concern, they can be easily treated with cryotherapy, electrodessication or snip-excision. Despite their high incidence data about their etiopathogenesis are scarce in the medical literature. We describe a patient who developed multiple skin tags arranged in a linear fashion suggesting an etiopathogenic role for friction.

A review of the histopathology of cigarette smoke-induced lung cancer in rats and mice

In the past several years an increased number of lung tumors has been reported in laboratory studies of rats and mice after lifetime exposure to mainstream cigarette smoke. Proliferative epithelial lesions are present in the lungs of both species and are apparent antecedent lesions to benign and malignant tumors. Both species have alveolar epithelia hyperplasia, alveolar adenomas, and alveolar carcinomas. The incidence of all three are more in the rats. In addition, mice also have bronchiolar epithelial hyperplasia and bronchial papillomas not found in rats. Rats have a low incidence of squamous cyst that is not found in mice. Lung tumors in rats and mice are found at the end of the life span and rarely metastasize. The characteristics of the lung tumors, and the proliferative changes associated with the tumors, are important in helping understand the mechanisms of lung cancer induction. These studies in rats and mice allow new approaches to the study of cigarette smoke-induced changes in the lung.

Papillomavirus infection in cattle: viral and chemical cofactors in naturally occurring and experimentally induced tumours

Six different types of bovine papillomavirus (BPV-1 to BPV-6) have been identified and classified into two subgroups: subgroup A, which induce fibropapillomas, and subgroup B, which induce true epithelial papillomas. BPV-4, a member of subgroup B, is the aetiological agent of papillomas of the upper alimentary canal, which can become a focus for transformation to squamous-cell carcinomas in animals feeding on bracken fern. Strong circumstantial evidence suggests that the progression to malignancy is due to the interplay between BPV-4 and carcinogen(s) present in the fern. The carcinomas of the upper alimentary canal are often accompanied by adenomas and adenocarcinomas of the lower bowels, and by carcinomas and hemangiosarcomas of the urinary bladder. Bracken-grazing animals are also heavily immunosuppressed. Florid papillomatosis of the upper alimentary canal and cancers of the urinary bladder have been experimentally reproduced in animals either kept on a diet of bracken or immunosuppressed with azathioprine. Several bladder cancers contained multiple episomal copies of BPV-2 DNA, suggesting that this virus, or its genome, can be present in a latent form, and that it can be implicated in malignant transformation. Further indication of latent infection is provided by the onset of skin warts in papillomatosis-free animals. These warts developed at sites of damaged skin and harboured either BPV-1 or BPV-2. BPV-4 DNA has not been found in the naturally occurring cancers of the upper alimentary canal and of the lower bowels, except in one tongue carcinoma and one transforming papilloma, indicating that the viral genome is not required for the maintenance of the malignant state in the alimentary canal.

The high-risk benign tumor: evidence from the two-stage skin cancer model and relevance for human cancer

Benign tumors that form following chemical initiation and promotion in the mouse skin can be grouped into two classes. The majority of papillomas do not progress to squamous cell carcinoma (SCC), and these are designated as low-risk or terminally benign papillomas. In contrast, a much smaller group forms the true precursor to the SCC, and these have a significantly higher frequency and rate of malignant conversion than the bulk of low-risk papillomas. In standard two-stage carcinogenesis studies both tumor types are present, but grossly indistinguishable. Here we describe properties and potential origins of high-risk papillomas and discuss the relevance of this model for certain human cancers with defined premalignant states.

The epidemiology of human papillomavirus infection and cervical cancer

Cervical cancer has been recognized as a rare outcome of a common Sexually Transmitted Infection (STI). The etiologic association is restricted to a limited number of viral types of the family of the Human Papillomaviruses (HPVs). The association is causal in nature and under optimal testing systems, HPV DNA can be identified in all specimens of invasive cervical cancer. As a consequence, it has been claimed that HPV infection is a necessary cause of cervical cancer. The evidence is consistent worldwide and implies both the Squamous Cell Carcinomas (SCC), the adenocarcinomas and the vast majority (i.e. > 95%) of the immediate precursors, namely High Grade Squamous Intraepithelial Lesions (HSIL)/Cervical Intraepithelial Neoplasia 3 (CIN3)/Carcinoma in situ. Co-factors that modify the risk among HPV DNA positive women include the use of oral contraceptives (OC) for five or more years, smoking, high parity (five or more full term pregnancies) and previous exposure to other sexually transmitted diseases such as Chlamydia Trachomatis (CT) and Herpes Simplex Virus type 2 (HSV-2). Women exposed to the Human Immunodeficiency Virus (HIV) are at high risk for HPV infection, HPV DNA persistency and progression of HPV lesions to cervical cancer.

Photocarcinogenesis study of glycolic acid and salicylic acid (CAS Nos. 79-14-1 and 69-72-7) in SKH-1 mice (simulated solar light and topical application study)

Acidic solutions have been used for decades to treat a variety of skin conditions. Many of these solutions consist of organic acids with a hydroxy group on a carbon adjacent to the carbonyl carbon and are referred to as alpha-hydroxy acids (AHA). Organic acids with hydroxy groups on the second carbon from the carbonyl carbon are referred to as beta-hydroxy acids (BHA). Both AHA and BHA are used to treat various skin conditions. One of the most widely used AHA is glycolic acid, while salicylic acid is a commonly used BHA. Chemical peels containing 20% to 70% glycolic acid have been used by dermatologists to treat ichthyosis, acne, xerosis, actinic keratosis, seborrheic keratoses, warts, and psoriasis. AHA have recently been used to treat photoaged skin and are now included in many commercially available cosmetic skin treatments. When used in a formulation for a chemical peel, topical treatment of skin with AHA and BHA can result in removal of the stratum corneum, alteration of the skin's histology, and increased cell proliferation in the basal layer of the epidermis. Since AHA and BHA are used to correct photoaged skin, and since exposure to sunlight of skin treated with AHA or BHA is likely, studies were designed to determine the effects of topical application of creams containing AHA (0%, 4%, or 10% glycolic acid, pH 3.5) or BHA (0%, 2%, or 4% salicylic acid, pH 4.0) on the photocarcinogenesis of simulated solar radiation using a filtered 6.5 kW xenon arc light source [simulated solar light (SSL)]. Male and female Crl:SKH-1 (hr-/hr-) hairless mice were exposed to glycolic acid or salicylic acid alone or in combination with SSL for 40 weeks, and the mice were followed for an additional 12 weeks. 1-YEAR STUDY IN MICE: Groups of 36 male and 36 female mice were exposed to 0.0, 0.3, 0.6, or 0.9 minimal erythema dose (MED) of SSL during the afternoon (1200 to 1600 hours) 5 days per week for 40 weeks. Groups of 18 male and 18 female mice were treated in the morning (0800 to 1100 hours) with 2 mg/cm2 control cream, 4% glycolic acid cream, 10% glycolic acid cream, 2% salicylic acid cream, or 4% salicylic acid cream on the dorsal skin, and in the afternoon (1200 to 1600 hours) with 0.3 MED of SSL 5 days per week for 40 weeks. Additional groups of 18 male and 18 female mice were treated in the morning (0800 to 1100 hours) with 2 mg/cm2 control cream, 4% glycolic acid cream, 10% glycolic acid cream, 2% salicylic acid cream, or 4% salicylic acid cream on the dorsal skin, and in the afternoon (1200 to 1600 hours) with 0.6 MED of SSL 5 days per week for 40 weeks. All mice were held an additional 12 weeks following the end of treatment. There were no effects of SSL exposure or topical treatment on the body weights of the mice. Increasing doses of SSL resulted in an SSL-dose trend in survival, with the greatest dose of SSL causing the earliest removal. This effect was present in both the untreated and control cream treated mice. The only consistent effect of glycolic acid on survival was a dose-dependent increase in survival of females at 0.3 MED SSL. Survival was increased in mice exposed to 0.6 MED of SSL and treated with 2% and 4% salicylic acid compared to mice treated with 0.6 MED and treated only with the vehicle. This effect was not observed in the mice treated with 0.0 and 0.3 MED of SSL and salicylic acid compared to the control groups. The mean or median time to first skin tumor of at least 1 mm decreased with increasing SSL exposure concentration in mice that were not treated with cream. Addition of the control cream resulted in a decrease in the time to tumor at 0.3 and 0.6 MED of SSL in male and female mice. The addition of glycolic acid (4% or 10%) did not affect the time to tumor in male or female mice at either SSL dose when compared to mice receiving the control cream. When compared to mice receiving control cream, the inclusion of 4% salicylic acid in the cream increased the time to tumor for male mice receiving 0.3 or 0.6 MED of SSL and female mice receiving 0.3 MED of SSL. The results indicate that inclusion of glycolic acid in the topical cream had no effect on the time required to induce tumors by SSL; however, inclusion of salicylic acid at 4% in the cream was photoprotective, increasing the time required to achieve median tumor incidence at a corresponding dose of SSL and control cream. The skin tumors induced by SSL in mice were squamous cell papilloma, carcinoma in situ, and squamous cell carcinoma. Except for papilloma in male mice, the tumors were induced in a dose-dependent manner by SSL in male and female mice. In male and female mice treated with control cream, the exposure to SSL caused significant increases in the incidences of carcinoma in situ, squamous cell carcinoma, and the combined incidence of carcinoma in situ and squamous cell carcinoma. When male or female mice were exposed to 0.3 or 0.6 MED SSL, the inclusion of 4% or 10% glycolic acid did not affect the induction of skin neoplasms over the incidence detected when the control cream was used, with the single exception of a glycolic acid dose-trend in squamous cell carcinoma incidence in male mice receiving 0.3 MED SSL. The inclusion of salicylic acid in the cream that was topically applied to female mice did not affect squamous cell papilloma formation at either SSL dose. The incidence of carcinoma in situ was decreased in male and female mice at 0.3 MED SSL when treated with 4% salicylic acid. A salicylic acid dose-trend was also observed in both sexes at 0.3 MED SSL.

CONCLUSIONS

These experiments investigated the impact of topical application of a cosmetic formulation containing 4% or 10% glycolic acid (pH 3.5) or 2% or 4% salicylic acid (pH 4) on the photocarcinogenesis of filtered 6.5 kW xenon arc simulated solar light (SSL) in SKH-1 hairless mice. Taking into consideration the survival data, time to tumor data, and the pathology results, glycolic acid did not alter the photocarcinogenesis of SSL, and salicylic acid was photoprotective, reducing the carcinogenicity of 0.3 MED SSL.

Juvenile recurrent respiratory papillomatosis: still a mystery disease with difficult management

Juvenile recurrent respiratory papillomatosis (RRP) is the most common benign neoplastic disease of the larynx in children and adolescents and has a significant impact on patients and the health care system with a cost ranging from $60,000 to $470,000 per patient. The aim of this paper is to review the current literature on RRP and summarize the recent advances. RRP is caused by human papillomavirus (HPV; mainly by types 6 and 11). Patients suffer from wart-like growths in the aerodigestive tract. The course of the disease is unpredictable. Although spontaneous remission is possible, pulmonary spread and malignant transformation have been reported. Surgical excision, including new methods like the microdebrider, aims to secure an adequate airway and improve and maintain an acceptable voice. Repeated recurrences are common and thus overenthusiastic attempts to eradicate the disease may cause serious complications. When papillomas recur, old and new adjuvant methods may be tried. In addition, recent advances in immune system research may allow us to improve our treatment modalities and prevention strategies. A new vaccine is under trial to prevent HPV infection in women; the strongest risk factor for juvenile RRP is a maternal history of genital warts (transmitted from mother to child during delivery). Better understanding of the etiology of the disease and the knowledge of all available therapies is crucial for the best management of the affected patients.

[Cervical-uterine-cancer associated factors in Nayarit state, Mexico]

OBJECTIVE

To establish the association between high-grade intraepithelial lesions and cervical-uterine-cancer, and the infection by human papillomavirus, genetic antecedents, socioeconomics, sexual behavior and gynecology and obstetrics factors in women of the State of Nayarit, Mexico.

MATERIALS AND METHODS

With a case-control design were studied 66 cases of high-grade intraepithelial lesions and cervical-uterine-cancer, and 132 controls. The information upon the risk factors was obtained by the application of a structured questionnaire. Polymerase Chain Reaction executed the virus identification. In the statistical analysis the association was obtained by odds ratio. The statistical significance was evaluated by the chi-square-Fisher and Student t tests, and multivariate logistic regression was used to explain the factors' influence.

RESULTS

In women with high-risk squamous intraepithelial lesions and cervical-uterine-cancer, the most frequently high-risk human papillomavirus found were: 18, 35, 58, 16, 31, 33 and 51.

CONCLUSIONS

Familial data of cervical-uterine-cancer, socioeconomic level, number of sexual partners, data of sexual transmitted diseases, and infection due to human papillomavirus 18 and 35 are the factors related to high-risk squamous intraepithelial lesions and cervical-uterine-cancer.

An Xpd mouse model for the combined xeroderma pigmentosum/Cockayne syndrome exhibiting both cancer predisposition and segmental progeria

Inborn defects in nucleotide excision DNA repair (NER) can paradoxically result in elevated cancer incidence (xeroderma pigmentosum [XP]) or segmental progeria without cancer predisposition (Cockayne syndrome [CS] and trichothiodystrophy [TTD]). We report generation of a knockin mouse model for the combined disorder XPCS with a G602D-encoding mutation in the Xpd helicase gene. XPCS mice are the most skin cancer-prone NER model to date, and we postulate an unusual NER dysfunction that is likely responsible for this susceptibility. XPCS mice also displayed symptoms of segmental progeria, including cachexia and progressive loss of germinal epithelium. Like CS fibroblasts, XPCS and TTD fibroblasts from human and mouse showed evidence of defective repair of oxidative DNA lesions that may underlie these segmental progeroid symptoms.

Acanthosis nigricans, Papillomatosis mucosae und „tripe palms” bei einem Patienten mit metastasiertem Magenkarzinom

HISTORY AND CLINICAL FINDINGS

A 48-year-old obese man presented with thickening, coarseness and hyperpigmentation of the skin, especially of the intertriginous areas, papillomatous to verrucous lesions of the lips and buccal oral mucosa, and hyperkeratosis of the palms ("tripe palms") and soles. He was obese, reported sleep apnea and had a history of hyperuricemia, mixed hyperlipidemia and previous myocardial infarction. He was on a maintenance dose of a proton pump inhibitor for chronic gastro-esophageal reflux.

EXAMINATIONS

Immunohistochemical studies of the skin lesion revealed increased epidermal immunoreactivity for the melanocortin-1-receptor. Increased levels of tumor markers CA 19-9 (141100 U/ml), CA 72-4 (755 U/ml) and CEA (189 ng/ml) were found in the serum. Gastroscopic findings were suspicious of adenocarcinoma of the stomach: it was classified histologically as a signet-ring cell, non-mucinous adenocarcinoma. At the time of diagnosis the tumor had already metastasized to perigastric and peripancreatic lymph nodes with peritoneal carcinosis.

TREATMENT AND COURSE

Since a curative resection was impossible a gastrojejunostomy was carried out. After this the patient received several courses of chemotherapy according to different schemes. Serum tumor marker levels and cutaneous signs regressed several times.

CONCLUSIONS

Marked acanthosis nigricans -- especially when associated with further cutaneous markers of malignancy, e.g. mucocutaneous papillomatosis or so-called tripe palms -- calls for thorough search for malignant tumor, also if metabolic or endocrinological abnormalities co-exist. A pathogenetic role of a-melanocyte-stimulating hormone in the development of the skin changes is suggested.

Extensive papillomatosis of the palate exhibiting epithelial dysplasia and HPV 16 gene expression in a renal transplant recipient

We report a unique case of extensive papillomatosis of the palate in a renal transplant recipient. The condition resembled inflammatory papillary hyperplasia; it exhibited severe epithelial dysplasia and concurred with generalized gingival hyperplasia. We document and discuss the probable multifactorial etiology of the lesions, including evidence for human papillomavirus (HPV) type 16 expression, as detected by in situ reverse transcription polymerase chain reaction. This report illustrates the need for careful clinical investigation and follow-up of immunosuppressed individuals presenting with apparently benign, common oral lesions.

Proliferative verrucous leukoplakia and field cancerization: report of a case

Proliferative verrucous leukoplakia (PVL) is a multi-focal oral pre-malignant lesion, proliferative in nature, with a tendency to recur despite adequate therapy, and a high rate of malignant transformation. The field cancerization phenomenon may explain the characteristic behaviour of PVL. A case of PVL is presented and the field cancerization concept is discussed.

Risk of oral nonmalignant lesions associated with human papillomavirus infection, betel quid chewing, and cigarette smoking in Taiwan: an integrated molecular and epidemiologic study

CONTEXT

In contrast to previous studies about the association of oral squamous cell carcinoma with human papillomavirus (HPV) 16/18, the associations between nonmalignant oral lesions (chronic inflammation, submucous fibrosis, leukoplakia, and squamous papilloma) and HPV are much less well understood.

OBJECTIVE

We conducted this study using an in situ polymerase chain reaction in situ hybridization assay, which is one of the most sensitive methods for in situ viral detection. Other known oral cancer risk factors, including betel quid chewing and cigarette smoking, were also analyzed.

DESIGN

Oral specimens from 23 patients with submucous fibrosis, 36 patients with leukoplakia, 22 patients with squamous papilloma, and 21 patients without significant lesions were analyzed for the presence of HPV DNA. Their betel quid chewing and cigarette smoking histories were reviewed.

RESULTS

HPV-16 and HPV-18 were frequently identified in all 3 oral lesions (61.5% and 42.1%), while HPV-6 and HPV-11 were seen only in squamous papilloma (21.1% and 5.0%). HPV-18, betel quid chewing, and smoking were significantly associated with leukoplakia and squamous papilloma, while only betel quid chewing and smoking were significantly associated with submucous fibrosis. Multivariate analysis showed that the betel quid chewing habit remained an independent factor for leukoplakia and squamous papilloma.

CONCLUSIONS

Our data indicated that betel quid chewing and smoking habits are 2 important risk factors for these nonmalignant or premalignant oral lesions, while for high-risk HPV, only HPV-18--not HPV-16--is a significant risk factor for leukoplakia and squamous papilloma.

Intraoral lesions associated with sebaceous nevus syndrome

The sebaceous nevus syndrome describes the rare association of a sebaceous nevus with systemic features such as mental retardation, seizures and colobomas (among others). It is thought to be a cutaneous mosaic inherited as a paradominant trait. Three cases are provided illustrating the intraoral manifestations of the syndrome. The first histological comparison of contiguous mucosal and cutaneous lesions is provided. We also describe the possible association of SFM syndrome with a benign fibrous histiocytic lesion of the mandible. This and other mandibular tumors associated with the sebaceous nevus syndrome may have significant implications for patients. Awareness of the potential presence or development of significant intraoral lesions in association with the sebaceous nevus syndrome is important for those involved in the care of patients with this syndrome.

[Endoscopic removal of sinonasal tumors]

OBJECTIVES

To evaluate the efficacy of endoscopic surgery for sinonasal tumors.

PATIENTS AND METHODS

Clinical records of 20 patients (10 males, 10 females; mean age 34; range 12 to 63 years) who underwent endoscopic tumor resection with diagnosis of sinonasal tumor between January 1998 and August 2004 were retrospectively reviewed. Patients who were operated by transnasal endoscopic surgery or by combined (endoscopic or external) surgical methods were included in the study. Patients were reviewed for age, sex, pathologic diagnosis and tumor location, surgical techniques, need for additional surgery, complications, recurrence, and follow-up period.

RESULTS

There were five osteomas, one fibrous dysplasia, one ossifying fibroma, seven inverted papillomas, one oncocytic papilloma, three angiofibromas, one schwannoma, and one esthesioneuroblastoma. The patients follow-up period ranged between 6 months and 6 years (mean 26 months). The fibrous dysplasia involving the posterior ethmoid sinuses was subtotally resected due to its close proximity to the optic nerve. One inverted papilloma of the maxillary sinus was resected by a combined endoscopic and Caldwell-Luc approach. A combined endoscopic intranasal and external frontoethmoidectomy approach was performed for the removal of frontal sinus schwannoma. Recurrence was observed in one of the inverted papilloma cases. Total removal of the tumors was achieved in all other cases without any complications or recurrences.

CONCLUSION

Low recurrence rates in our series showed that endoscopic resection of nasal-paranasal sinus tumors in selected cases, may be an appropriate method as solely or in combined with other surgical techniques for experienced surgeons.

Cowden's syndrome. Case report, with reference to an affected family

Cowden's syndrome is a rare genodermatosis characterized by multiple hamartomas in several tissues and organs derived from all three embryonic layers. Clinical features of Cowden's disease are explained by the mutation of the PTEN tumour suppressor gene, whose modification leads to an uncoordinated growth of tissues. The importance of this disease lies in the increased susceptibility to malignization of some lesions, specially breast, thyroid and genito-urinary tract lesions. As a result, the disease has been considered a preneoplasic condition. Despite its varied phenotypic expression, this disease is generally unknown. Consequently, many cases are undiagnosed or diagnosis comes at a late stage, what points out the importance of an early diagnosis of the disease so the patient can have periodic check-ups to prevent malignant diseases. A family case is presented here, whose diagnosis was based upon oral clinical findings and which most distinct systemic alteration is the presence of hamartomatous polyps in the digestive tract in several family members.

Anogenital and respiratory tract human papillomavirus infections among children: age, gender, and potential transmission through sexual abuse

OBJECTIVES

To evaluate human papillomavirus (HPV) presentation among children <13 years of age and its association with suspected child sexual abuse (CSA), and to assess sexual abuse consideration among different clinical services treating these children.

METHODS

Records of children <13 years of age from 1985 to 2003 were selected for review if the children had a HPV-related International Classification of Diseases, Ninth Revision, code or had been examined in the CSA clinic. Abstracted data included demographic features, clinical findings, clinical services involved, age at diagnosis, age when care was first sought, and age when symptoms were first noted.

RESULTS

HPV was identified by clinical examination and/or biopsy for 124 children, 40 with laryngeal lesions, 67 with anogenital lesions, 10 with oral lesions, and 7 with both anogenital and oral lesions. The mean age at HPV diagnosis was 4.0 +/- 2.9 years, compared with 6.4 +/- 3.0 years for 1565 HPV-negative children. Among 108 HPV cases with data for age when symptoms were first noted, the mean age was 3.3 +/- 2.9 years (median: 2.2 years) for children with anogenital and oral HPV and 2.4 +/- 2.3 years (median: 1.9 years) for children with laryngeal HPV. Among HPV-positive patients, 56% were female, compared with 82% of HPV-negative children. Fifty-five (73%) of 75 children with anogenital HPV infections were referred to the CSA clinic for evaluation, compared with none of 49 children with laryngeal or oral HPV infections treated by the otolaryngology service. Laryngeal cases presented earlier than anogenital and oral lesions. Abuse was considered at least possible for 17 of 55 children with any CSA evaluation. The mean age of likely abused, HPV-positive children was 6.5 +/- 3.8 years (median: 5.3 years), compared with 3.6 +/- 2.3 years (median: 2.6 years) for likely not abused, HPV-positive children. The likelihood of possible abuse as a source of HPV infection increased with age. The positive predictive value of HPV for possible sexual abuse was 36% (95% confidence interval: 13-65%) for children 4 to 8 years of age and 70% (95% confidence interval: 35-93%) for children >8 years of age.

CONCLUSIONS

The data from this epidemiologic study of HPV suggest that many anogenital and laryngeal HPV infections among preadolescent children are a result of nonsexual horizontal transmission, acquired either perinatally or postnatally. It seems that many children >2 years of age acquire HPV infection from nonsexual contact. Different subspecialties vary greatly in their suspicion and evaluation of CSA. At this time, there remains no clear age below which sexual abuse is never a concern for children with anogenital HPV infections. Every case needs a medical evaluation to determine whether enough concern for abuse exists to pursue additional investigations.

Sustained localized expression of ligand for the activating NKG2D receptor impairs natural cytotoxicity in vivo and reduces tumor immunosurveillance

Upregulation of the inducible gene products MICA (human) and Rae-1 (mouse) may promote tumor surveillance and autoimmunity by engaging the activating receptor NKG2D on natural killer (NK) cells and T cells. Nevertheless, sustained expression of MICA by tumors can also elicit NKG2D downregulation, perhaps indicating 'immunoevasion'. Investigating this paradox, we report here that constitutive Rae-1epsilon transgene expression in normal epithelium elicited local and systemic NKG2D downregulation, generalized but reversible defects in NK cell-mediated cytotoxicity and mild CD8(+) T cell defects. The extent of NKG2D downregulation correlated well with the incidence and progression of cutaneous carcinogenesis, emphasizing the utility of NKG2D as a marker of tumor resistance. Thus, NKG2D engagement is a natural mediator of immunosurveillance, which can be compromised by locally sustained ligand expression but potentially restored by innate immune activation.

Fibropapillomatosis in stranded green turtles (Chelonia mydas) from the eastern United States (1980-98): trends and associations with environmental factors

We examined data collected by the US Sea Turtle Stranding and Salvage Network on 4,328 green turtles (Chelonia mydas) found dead or debilitated (i.e., stranded) in the eastern half of the USA from Massachusetts to Texas during the period extending from 1980 to 1998. Fibropapillomatosis (FP) was reported only on green turtles in the southern half of Florida (south of 29 degrees N latitude). Within this region, 22.6% (682/3,016) of the turtles had tumors. Fibropapillomatosis was more prevalent in turtles found along the western (Gulf) coast of Florida (51.9%) than in turtles found along the eastern (Atlantic) coast of Florida (11.9%) and was more prevalent in turtles found in inshore areas (38.9%) than in turtles found in offshore areas (14.6%). A high prevalence of FP corresponded to coastal waters characterized by habitat degradation and pollution, a large extent of shallow-water area, and low wave energy, supporting speculation that one or more of these factors could serve as an environmental cofactor in the expression of FP. A high prevalence of FP did not correspond to high-density green turtle assemblages. Turtles with tumors were found most commonly during the fall and winter months, and the occurrence of tumors was most common in turtles of intermediate size (40-70-cm curved carapace length). Stranded green turtles with tumors were more likely to be emaciated or entangled in fishing line and less likely to have propeller wounds than were stranded green turtles without tumors. Turtles with and without tumors were equally likely to show evidence of a shark attack. The percent occurrence of tumors in stranded green turtles increased from approximately 10% in the early 1980s to over 30% in the late 1990s. Fibropapillomatosis was first documented in southernmost Florida in the late 1930s and spread throughout the southern half of Florida and the Caribbean during the mid-1980s. Because green turtles living in south Florida are known to move throughout much of the Caribbean, but are not known to move to other parts of the USA or to Bermuda, the spread and current distribution of FP in the western Atlantic, Gulf of Mexico, and Caribbean can be explained by assuming FP is caused by an infectious agent that first appeared in southern Florida. Aberrant movements of captive-reared turtles or of turtles that are released into areas where they were not originally found could spread FP beyond its current distribution.

Knockout mice reveal a tumor suppressor function for Testin

The Testin (TES) gene was previously identified as a putative human tumor suppressor gene at 7q31.2, a region that is frequently deleted in hematopoietic malignancies, as well as in epithelial tumors. To determine whether TES acts as a tumor suppressor in vivo, we generated a Tes knockout mouse and then used it in an established model of carcinogen-induced gastric cancer. In mice a zinc-deficient (ZD) diet enhances cellular proliferation in the forestomach and susceptibility to N-nitrosomethylbenzylamine (NMBA)-induced carcinogenesis. Five-week-old Tes wild-type (+/+), heterozygous (+/-), and homozygous (-/-) mice were divided into four groups: mice fed a zinc-sufficient diet (ZS); mice fed a ZD diet; ZS fed plus NMBA-treated mice (ZS+NMBA), and ZD fed plus NMBA-treated mice (ZD+NMBA). After 4 weeks, the ZS+NMBA and ZD+NMBA groups were treated with three intragastric doses of NMBA. Animals were killed 8 weeks after NMBA administration: 25% of +/+ mice developed benign lesions; 88% of +/- showed multiple papillomas, atypical glandular metaplasia, and squamous cell carcinomasl; and 81% of -/- mice displayed very large papillomas, squamous cell carcinomas, and adenocarcinomas. A statistically significant difference in tumor incidence was found between +/- versus +/+ and -/- versus +/+ (P < 0.0001). These data suggest that Tes functions as a tumor suppressor gene in vivo.

An antitumorigenic role for murine 8S-lipoxygenase in skin carcinogenesis

The levels of 8S-lipoxygenase (8S-LOX) expression and of its arachidonic acid metabolite, 8-hydroxyeicosatetraenoic acid (8-HETE), are highly elevated in the early stages of mouse skin carcinogenesis. On the other hand, several reports showing that 8-HETE is also closely associated with keratinocyte differentiation raise a question concerning the role of 8S-LOX/8-HETE in skin carcinogenesis. To address that question, here we conducted a series of gain-of-function studies. Skin targeted loricrin 8S-LOX/C57BL/6J transgenic mice showed a more differentiated epidermal phenotype as well as a 64% reduced papilloma development in a two-stage skin carcinogenesis protocol. Forced expression of 8S-LOX in MT1/2 cells, a murine papilloma cell line, also caused a more differentiated appearance as well as keratin 1 expression. Overexpression of 8S-LOX in CH72 cells, a murine carcinoma cell line, inhibited cell proliferation by 30% in vitro and by 86% in in vivo xenografts. Exogenous addition of 5 muM 8-HETE to CH72 cells caused cell cycle arrest at the G1 phase. Finally, immunohistochemical analyses showed 8S-LOX protein expression was strictly confined to the differentiated compartment of mouse skin and throughout tumorigenesis. Collectively, these data suggest that 8S-LOX plays a role as a prodifferentiating, antitumorigenic, and tumor suppressing gene in mouse skin carcinogenesis.

Large cutaneous rabbit papillomas that persist during cyclosporin A treatment can regress spontaneously after cessation of immunosuppression

Cottontail rabbit papillomavirus (CRPV)-induced papillomas can progress into malignant carcinomas, remain persistent or regress. Both host immunity and virus genetic background play critical roles in these events. To test how host immunity influences CRPV-induced papilloma evolution, both EIII/JC (inbred) and New Zealand White (outbred) rabbits were treated with an immunosuppressive drug, cyclosporin A (CsA), for 80 days and the regression of three regressive constructs, H.CRPVr (a CRPV regressive strain), H.CRPVp-E6r (a progressive strain with regressive E6) and H.CRPVp-CE6rm (H.CRPVp with the carboxyl terminal of regressive E6, containing mutations at amino acid residues E252G, G258D and S259P) was checked. Papillomas induced by H.CRPVr and H.CRPVp-E6r on control inbred and outbred rabbits regressed totally around week 8, whereas papillomas on all CsA-treated rabbits grew progressively. After cessation of CsA treatment, papillomas began to regress in six outbred rabbits: 14 of 18 papillomas induced by CRPVr, 11 of 18 papillomas induced by H.CRPVp-E6r and eight of 10 papillomas induced by H.CRPVp-CE6rm regressed around week 21. In four CsA-treated inbred rabbits, two of 17 papillomas induced by H.CRPVr and one of 17 papillomas induced by H.CRPVp-E6r regressed. These data indicate that papillomas induced by a regressive CRPV strain can become persistent in the transiently immunosuppressed host. However, returning immunity can lead to regression and clearance of large papillomas (with increased antigenicity) in an outbred population, whilst these same antigenic papillomas persist in inbred rabbits.

Epizootic cutaneous papillomatosis, cortisol and male ornamentation during and after breeding in the roach Rutilus rutilus

The prevalence of epidermal papillomatosis in roach is known to peak during the spawning period and to be higher in males than in females. The high occurrence of papillomatosis in polluted waters suggests that stress may contribute to the outbreak of the disease. However, little is known about breeding-induced stress in fish and its relationship with diseases. In this study, plasma cortisol concentration, hematocrit and the relative size of the spleen were determined in healthy and diseased male and female roach Rutilus rutilus during and shortly after spawning in a wild population. In addition, the sexual ornamentation (breeding tubercles on the lateral sides and on the frontal) of male roach during spawning was examined. Plasma cortisol concentration was higher during than after the spawning period, and higher in males than in females during spawning, indicating a spawning-induced stress and higher spawning stress among males. There was no correlation between cortisol concentration and the intensity of papillomatosis (number of scales under papilloma tumors) among the diseased fish. However, the significant interaction sex x disease status revealed by ANCOVA suggested that diseased males could be more prone to increased cortisol levels than diseased females or healthy males. Hematocrit values (ratio of the volume of red blood cells to total volume of blood) but not condition factor were lowered in papilloma-diseased fish after spawning. The relative size of the spleen was greater in males than in females. The number of frontal breeding tubercles correlated negatively with the intensity of papillomatosis. Experimental studies are needed to investigate the association of papillomatosis with stress and cortisol.

Papillomviruserkrankungen

Papillomaviruses are prevalent throughout the world. They can cause warts or papillomas. Some papillomaviruses are also involved in the pathogenesis of malignant tumors. Cutaneous and anogenital warts are the most frequent viral disease of the skin. The incidence of verrucae vulgaris and condylomata is estimated to be 7-10% in the European population and 1% in the American population. HPV infections can be verified by clinical examination, cytology and histology, detection of antibodies, molecular techniques and directly via viral structures. Antibodies against HPV are considered markers for prolonged infection and cumulatively high expression of viral particles since they persist with low titers years after a lesion has resolved. Sensitivity only reaches 50-60% even in HPV DNA-positive patients. Serodiagnosis does not appear to be appropriate for routine practice. No virustatic treatment exists. Depending on wart-specific factors, compliance of the patient, and experience of the attending therapist, all ablative, chemodestructive or novel immuno modulatory procedures are comparable. However, there are enormous differences in price and effort required for treatment, which should be considered when choosing the method.