A clinical and molecular portrait of non-metastatic anal squamous cell carcinoma.

Anal squamous cell carcinoma (ASCC) is a rare gastrointestinal malignancy associated with high-risk Human papillomavirus (HPV) infection. Despite improved outcomes in non-metastatic ASCC, definitive chemoradiotherapy constitutes the standard treatment for localized disease. Evidences for predictive and prognostic biomarkers are limited. Here, we performed a viral, immune, and mutational characterization of 79 non-metastatic ASCC patients with complete definitive chemoradiotherapy. HPV-16 was detected in 91% of positive cases in single infections (78%) or in coinfections with multiple genotypes (22%). Fifty-four percent of non-metastatic ASCC cases displayed mutations affecting cancer driver genes such as PIK3CA (21% of cases), TP53 (15%), FBXW7 (9%), and APC (6%). PD-L1 expression was detected in 57% of non-metastatic ASCC. Increased PD-L1 positive cases (67%) were detected in patients with complete response compared with non-complete response to treatment (37%) (p = 0.021). Furthermore, patients with PD-L1 positive tumors were significantly associated with better disease-free survival (DFS) and overall survival (OS) compared with patients with PD-L1 negative tumors (p = 0.006 and p = 0.002, respectively). PD-L1 expression strongly impacts CR rate and survival of non-metastatic ASCC patients after standard definitive chemoradiotherapy. PD-L1 expression could be used to stratify good versus poor responders avoiding the associated morbidity with abdominal perineal resection.

Development of a hyperimmune equine serum therapy for COVID-19 in Argentina.

The disease named COVID-19, caused by the SARS-CoV-2 coronavirus, is currently generating a global pandemic. Vaccine development is no doubt the best long-term immunological approach, but in the current epidemiologic and health emergency there is a need for rapid and effective solutions. Convalescent plasma is the only antibody-based therapy available for COVID-19 patients to date. Equine polyclonal antibodies (EpAbs) put forward a sound alternative. The new generation of processed and purified EpAbs containing highly purified F(ab')2 fragments demonstrated to be safe and well tolerated. EpAbs are easy to manufacture allowing a fast development and scaling up for a treatment. Based on these ideas, we present a new therapeutic product obtained after immunization of horses with the receptor-binding domain of the viral Spike glycoprotein. Our product shows around 50 times more potency in in vitro seroneutralization assays than the average of convalescent plasma. This result may allow us to test the safety and efficacy of this product in a phase 2/3 clinical trial to be conducted in July 2020 in the metropolitan area of Buenos Aires, Argentina.

La enfermedad denominada COVID-19 es causada por el coronavirus SARS-CoV-2 y es actualmente considerada una pandemia a nivel global. El desarrollo de vacunas es sin duda la mejor estrategia a largo plazo, pero debido a la emergencia sanitaria, existe una necesidad urgente de encontrar soluciones rápidas y efectivas para el tratamiento de la enfermedad. Hasta la fecha, el uso de plasma de convalecientes es la única inmunoterapia disponible para pacientes hospitalizados con COVID-19. El uso de anticuerpos policlonales equinos (EpAbs) es otra alternativa terapéutica interesante. La nueva generación de EpAbs incluyen el procesamiento y purificación de los mismos y la obtención de fragmentos F(ab')2 con alta pureza y un excelente perfil de seguridad en humanos. Los EpAbs son fáciles de producir, lo cual permite el desarrollo rápido y la elaboración a gran escala de un producto terapéutico. En este trabajo mostramos el desarrollo de un suero terapéutico obtenido luego de la inmunización de caballos utilizando el receptor-binding domain de la glicoproteína Spike del virus. Nuestro producto mostró ser alrededor de 50 veces más potente en ensayos de seroneutralización in vitro que el promedio de los plasmas de convalecientes. Estos resultados nos permitirían testear la seguridad y eficacia de nuestro producto en ensayos clínicos de fase 2/3 a realizarse a partir de julio de 2020 en la zona metropolitana de Buenos Aires, Argentina.

Development of a hyperimmune equine serum therapy for COVID-19 in Argentina

The disease named COVID-19, caused by the SARS-CoV-2 coronavirus, is currently generating a global pandemic. Vaccine development is no doubt the best long-term immunological approach, but in the current epidemiologic and health emergency there is a need for rapid and effective solutions. Convalescent plasma is the only antibody-based therapy available for COVID-19 patients to date. Equine polyclonal antibodies (EpAbs) put forward a sound alternative. The new generation of processed and purified EpAbs containing highly purified F(ab’)2 fragments demonstrated to be safe and well tolerated. EpAbs are easy to manufacture allowing a fast development and scaling up for a treatment. Based on these ideas, we present a new therapeutic product obtained after immunization of horses with the receptor-binding domain of the viral Spike glycoprotein. Our product shows around 50 times more potency in in vitro seroneutralization assays than the average of convalescent plasma. This result may allow us to test the safety and efficacy of this product in a phase 2/3 clinical trial to be conducted in July 2020 in the metropolitan area of Buenos Aires, Argentina.

La enfermedad denominada COVID-19 es causada por el coronavirus SARS-CoV-2 y es actualmente considerada una pandemia a nivel global. El desarrollo de vacunas es sin duda la mejor estrategia a largo plazo, pero debido a la emergencia sanitaria, existe una necesidad urgente de encontrar soluciones rápidas y efectivas para el tratamiento de la enfermedad. Hasta la fecha, el uso de plasma de convalecientes es la única inmunoterapia disponible para pacientes hospitalizados con COVID-19. El uso de anticuerpos policlonales equinos (EpAbs) es otra alternativa terapéutica interesante. La nueva generación de EpAbs incluyen el procesamiento y purificación de los mismos y la obtención de fragmentos F(ab’)2 con alta pureza y un excelente perfil de seguridad en humanos. Los EpAbs son fáciles de producir, lo cual permite el desarrollo rápido y la elaboración a gran escala de un producto terapéutico. En este trabajo mostramos el desarrollo de un suero terapéutico obtenido luego de la inmunización de caballos utilizando el receptor-binding domain de la glicoproteína Spike del virus. Nuestro producto mostró ser alrededor de 50 veces más potente en ensayos de seroneutralización in vitro que el promedio de los plasmas de convalecientes. Estos resultados nos permitirían testear la seguridad y eficacia de nuestro producto en ensayos clínicos de fase 2/3 a realizarse a partir de julio de 2020 en la zona metropolitana de Buenos Aires, Argentina.

Human papillomavirus genotype distribution in cervical cancer biopsies from Nepalese women.

BACKGROUND: Cervical cancer (CC) is the leading cause of morbidity and mortality from cancer in Nepalese women. Nearly all cases of CC are caused by infection with certain genotypes of human papillomavirus (HPV). Data on HPV genotype distribution in Nepalese CC patients is sparse. We aimed to determine the distribution of HPV genotypes in biopsies of CC tissue from Nepalese women. METHODS: This study examined 248 archived paraffin-embedded tissue specimens from CC cases from patients of B.P. Koirala Memorial Cancer Hospital, Bharatpur, Chitwan, Nepal. DNA was extracted from the biopsies and HPV detection performed by PCR. HPV genotyping was then carried out by a reverse line hybridization technique capable of identifying 36 distinct HPV genotypes. RESULTS: Most of the samples were from tumors that had been designated by hospital pathologists as squamous cell carcinoma (77.6%). 165 of the 248 samples contained DNA of sufficient quality for rigorous PCR testing. All the analyzable specimens were positive for HPV. The most common HPV genotypes, in decreasing order of frequency were 16, 18, 45, 33, 52, 56 and 31; most were found as single infections (94.5%). Together, HPV types 16, 18, and 45 were found in 92% of the tumor samples. CONCLUSION: This study strengthens the knowledge-base of HPV genotype distribution in CC cases in Nepal. Hopefully, this information will be useful to the medical community and public health policy-makers in generating improved HPV-surveillance, -prevention and -treatment strategies in Nepal.

Prevalence and Geographical Variation of Prothrombin G20210A Mutation in Patients with Cerebral Vein Thrombosis: A Systematic Review and Meta-Analysis.

OBJECTIVES: To compare the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis against healthy controls, and evaluate geographical variations. DESIGN: Systematic review and meta-analysis of case control studies. METHODS: We conducted a systematic review of electronic databases including MEDLINE and EMBASE. The main outcome was the prevalence of prothrombin G20210A in patients with objectively confirmed cerebral vein or cortical vein thrombosis; we also analyzed individual country variations in the prevalence. The random-effects model OR was used as the primary outcome measure. RESULTS: In total 19 studies evaluated 868 cases of cerebral venous thrombosis and 3981 controls. Prothrombin G20210A was found in 103/868 of the patients with cerebral venous thrombosis and 105/3999 of the healthy controls [random effects pooled OR 5.838, 95% CI 3.96 to 8.58; I217.9%]. The prevalence of prothrombin G20210A was significantly elevated in Italian studies (OR 9.69), in Brazilian studies (OR 7.02), and in German studies (OR 3.77), but not in Iranian studies (OR 0.98). CONCLUSION: Prothrombin G20210A is significantly associated with cerebral venous thrombosis when compared to healthy controls, although this association is highly dependent on the country of origin.

Human papilloma virus risk factors for infection and genotype distribution in aboriginal women from Northern Argentina.

The mortality rate for cervical cancer (CC) in Northern Argentina is three times higher than the average for the country (7.8 deaths/100,000 women). We determined the prevalence and genotype distribution of human papillomavirus (HPV) in 227 sexually active women of the native Pilagá community in Formosa, Argentina. We also conducted an HPV-16 variant analysis and studied several community factors that might play a role in viral entry and infection. Endo and exocervical samples were tested for HPV DNA with MY09/11-PCR or with GP5+/6+-PCR. HPV was detected in 46.7% of the samples and 21 different types were found; the most frequent being HPV-16 (19.4%), -6 and -18 (5.3%), -58 (3.5%) and -31 and -33 (3.1%). In relation to HPV-16 variants, 68.2% were European and 31.8% Asian-American. Among the cofactors analyzed only disposal of hu man excreta to the open air (P=0.01) was significantly associated with HPV infection. Our prevalence estimates clearly show that Pilagá women are highly exposed to or infected with high risk HPV types and therefore are at a high risk of developing precancerous lesions and eventually CC at the population level.

Human papillomavirus risk factors for infection and genotype distribution in aboriginal women from Northern Argentina / Virus papiloma humano (hpv) en mujeres de la etnia Pilagá del nordeste argentino: Factores de riesgo de infección y distribución de tipos virales

The mortality rate for cervical cancer (CC) in Northern Argentina is three times higher than the average for the country (7.8 deaths/100 000 women). We determined the prevalence and genotype distribution of human papillomavirus (HPV) in 227 sexually active women of the native Pilagá community in Formosa, Argentina. We also conducted an HPV-16 variant analysis and studied several community factors that might play a role in viral entry and infection. Endo- and exocervical samples were tested for HPV DNA with MY09/11-PCR or with GP5+/6+-PCR. HPV was detected in 46.7% of the samples and 21 different types were found; the most frequent being HPV-16 (19.4%), -6 and -18 (5.3%), -58 (3.5%) and -31 and -33 (3.1%). In relation to HPV-16 variants, 68.2% were European and 31.8% Asian-American. Among the cofactors analyzed only disposal of human excreta to the open air (P=0.01) was significantly associated with HPV infection. Our prevalence estimates clearly show that Pilagá women are highly exposed to or infected with high risk HPV types and therefore are at a high risk of developing precancerous lesions and eventually CC at the population level.(AU)

La tasa de mortalidad por cáncer cervical (CC) en la región norte de la Argentina es tres veces más alta que la media del país (7.8 muertes/100 000 mujeres). En el presente trabajo se determinó la prevalencia de infección por virus papiloma humano (VPH) y la distribución y frecuencia de los genotipos en 227 mujeres sexualmente activas de la etnia aborigen Pilagá (Formosa, Argentina). También se realizó un análisis de las variantes intratípicas de VPH-16 presentes en la comunidad y se analizaron diversos factores socioculturales que podrían tener algún rol destacado en la transmisión de la infección viral. Se estudiaron muestras de células endo-exocervicales mediante PCR basadas en los cebadores MY09/11 y GP5+/6+ con posterior restricción enzimática y/o hibridación dot-blot. La infección por VPH fue detectada en el 46.7% de las mujeres analizadas. Fueron identificados 21 genotipos, de los cuales los más frecuentes fueron HPV-16 (19.4%), -6 y -18 (5.3%), -58 (3.5%) y -31 y -33 (3.1%). Respecto al HPV-16, se encontraron 68.2% de variantes europeas y 31.8% de asiático-americanas. Entre los cofactores analizados, solo la disposición de excretas al aire libre estuvo significativamente asociada con la infección por VPH (P = 0.01). Los datos obtenidos reflejan que la comunidad Pilagá está altamente expuesta a las infecciones por genotipos de alto riesgo de VPH, lo cual puede estar asociado a una alta incidencia de lesiones cervicales preneoplásicas y neoplásicas.(AU)

Human papillomavirus risk factors for infection and genotype distribution in aboriginal women from Northern Argentina / Virus papiloma humano (hpv) en mujeres de la etnia Pilagá del nordeste argentino: Factores de riesgo de infección y distribución de tipos virales

The mortality rate for cervical cancer (CC) in Northern Argentina is three times higher than the average for the country (7.8 deaths/100 000 women). We determined the prevalence and genotype distribution of human papillomavirus (HPV) in 227 sexually active women of the native Pilagá community in Formosa, Argentina. We also conducted an HPV-16 variant analysis and studied several community factors that might play a role in viral entry and infection. Endo- and exocervical samples were tested for HPV DNA with MY09/11-PCR or with GP5+/6+-PCR. HPV was detected in 46.7% of the samples and 21 different types were found; the most frequent being HPV-16 (19.4%), -6 and -18 (5.3%), -58 (3.5%) and -31 and -33 (3.1%). In relation to HPV-16 variants, 68.2% were European and 31.8% Asian-American. Among the cofactors analyzed only disposal of human excreta to the open air (P=0.01) was significantly associated with HPV infection. Our prevalence estimates clearly show that Pilagá women are highly exposed to or infected with high risk HPV types and therefore are at a high risk of developing precancerous lesions and eventually CC at the population level.

La tasa de mortalidad por cáncer cervical (CC) en la región norte de la Argentina es tres veces más alta que la media del país (7.8 muertes/100 000 mujeres). En el presente trabajo se determinó la prevalencia de infección por virus papiloma humano (VPH) y la distribución y frecuencia de los genotipos en 227 mujeres sexualmente activas de la etnia aborigen Pilagá (Formosa, Argentina). También se realizó un análisis de las variantes intratípicas de VPH-16 presentes en la comunidad y se analizaron diversos factores socioculturales que podrían tener algún rol destacado en la transmisión de la infección viral. Se estudiaron muestras de células endo-exocervicales mediante PCR basadas en los cebadores MY09/11 y GP5+/6+ con posterior restricción enzimática y/o hibridación dot-blot. La infección por VPH fue detectada en el 46.7% de las mujeres analizadas. Fueron identificados 21 genotipos, de los cuales los más frecuentes fueron HPV-16 (19.4%), -6 y -18 (5.3%), -58 (3.5%) y -31 y -33 (3.1%). Respecto al HPV-16, se encontraron 68.2% de variantes europeas y 31.8% de asiático-americanas. Entre los cofactores analizados, solo la disposición de excretas al aire libre estuvo significativamente asociada con la infección por VPH (P = 0.01). Los datos obtenidos reflejan que la comunidad Pilagá está altamente expuesta a las infecciones por genotipos de alto riesgo de VPH, lo cual puede estar asociado a una alta incidencia de lesiones cervicales preneoplásicas y neoplásicas.

First report on sexually transmitted infections among trans (male to female transvestites, transsexuals, or transgender) and male sex workers in Argentina: high HIV, HPV, HBV, and syphilis prevalence.

OBJECTIVES: Due to the scarce data on the prevalence of sexually transmitted infections (STIs) among male-to-female trans-sex workers (TSW) and male sex workers (MSW) in Argentina, the present study aimed to estimate the incidence of human immunodeficiency virus (HIV), and the prevalence of HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), and Treponema pallidum. Human papillomavirus (HPV) and Chlamydia trachomatis infections were tested among TSW. METHODS: Two hundred and seventy-three TSW and 114 MSW were recruited by nongovernmental organizations. HIV incidence was estimated by STARHS (serologic testing algorithm for recent HIV seroconversion). HPV and C. trachomatis infections were tested in anal cells from TSW. RESULTS: TSW showed significantly higher prevalences of HIV (34.1 vs. 11.4%), HBV (40.2 vs. 22.0%), and T. pallidum (50.4 vs. 20.4%) than MSW. TSW tested positive for HPV in 111/114 cases and for C. trachomatis in 4/80 cases. Investigation of HBV, HCV, HIV, and T. pallidum co-infections showed that 72% of TSW and 39% of MSW had at least one STI. T. pallidum was the most frequent mono-infection. The estimated HIV incidence was 10.7 per 100 person-years (95% confidence interval (CI) 3.8-17.7) for TSW and 2.3 per 100 person-years (95% CI 0-6.7) for MSW. CONCLUSIONS: The high prevalence of STIs and the high incidence of HIV demonstrate the great vulnerability of these high-risk populations and indicate the urgent need for preventive strategies on intervention and facilitation of access to healthcare programs.

Human papilloma virus genotype diversity of anal infection among trans (male to female transvestites, transsexuals or transgender) sex workers in Argentina.

BACKGROUND: Reports on the prevalence and genotypes of HPV among trans (male to female transvestites, transsexuals or transgender) sex workers (TSW) are scarce in the literature. OBJECTIVES: The aim of the study was to determine the infecting HPV genotypes among TSW in Argentina. STUDY DESIGN: 119 TSW were recruited. Anal cells were self collected with a cytobrush. HPV DNA detection was carried out by PCR and genotyping was performed by RLB. RESULTS: HPV prevalence was 97.4%. 103/111 HPV positive samples were genotyped. High risk genotypes were detected in 82.5%. Two or more coinfecting HPV genotypes were found in 70.9%. One case showed up to 10 different coinfecting types. The number of genotypes was not related to condom usage. Infection rates were similar for HIV positive (100%) and HIV negative (95.8%) participants. However, 18.8% of HIV negative had 4-9 different genotypes, while among HIV positive this percentage raised to 46.2% (p=0.006). Prevalence of high risk genotypes and the frequency of each high risk type were similar between HIV positive and HIV negative groups. According to the participants' answers HIV status showed no association with condom usage. CONCLUSIONS: The high HPV prevalence, the coinfection with multiple genotypes and the high frequency of high risk genotypes detected, together with a situation of extreme social marginalization, discrimination and stigmatization make this population to be of extreme vulnerability.

Association of DRB1 and DQB1 HLA class II polymorphisms in high-grade and neoplastic cervical lesions of women from Argentina.

OBJECTIVES: To investigate associations between HLA-DRB1 and HLA-DQB1 polymorphisms with low- and high-grade cervical lesions in Argentine population and the role human papillomavirus status in these associations. MATERIALS AND METHODS: Cervical biopsies and peripheral blood samples were taken from 32 patients with cervical intraepithelial neoplasia grade 1 (CIN 1) and 44 patients with cervical CIN 3 or invasive squamous cell carcinomas. Cervical cells and peripheral blood samples from 40 healthy women were included as control group. Human papillomavirus detection and typing were done by polymerase chain reaction (PCR) MY09, 11-restriction fragment length polymorphisms, or PCR 5+, 6+ dot-blot hybridization, and HLA DR/DQ typing by the PCR-sequence-specific oligonucleotide probes method. RESULTS: HLA-DRB1*04 and HLA-DQB1*0302 were found to be positive associated with the CIN 3/invasive squamous cell carcinomas subgroup, whereas HLA-DRB1*13 and HLA-DQB1*02 were negatively associated with the same group, when comparing to the control group. CONCLUSIONS: The data support the hypothesis that HLA-DRB1*04 and HLA-DQB1*0302 may be considered risk factors for malignant progression, whereas HLA-DRB1*13 and HLA-DQB1*02 may have a protective role. Further studies with a larger group are needed to confirm these susceptibility and protective roles in disease progression in Argentine population.

Human papillomavirus in oral lesions.

Growing evidence suggests a role for human papillomavirus (HPV) in oral cancer; however its involvement is still controversial. This study evaluates the frequency of HPV DNA in a variety of oral lesions in patients from Argentina. A total of 77 oral tissue samples from 66 patients were selected (cases); the clinical-histopathological diagnoses corresponded to: 11 HPV- associated benign lesions, 8 non-HPV associated benign lesions, 33 premalignant lesions and 25 cancers. Sixty exfoliated cell samples from normal oral mucosa were used as controls. HPV detection and typing were performed by polymerase chain reaction (PCR) using primers MY09, 11, combined with RFLP or alternatively PCR using primers GP5+, 6+ combined with dot blot hybridization. HPV was detected in 91.0% of HPV- associated benign lesions, 14.3% of non-HPV associated benign lesions, 51.5% of preneoplasias and 60.0% of cancers. No control sample tested HPV positive. In benign HPV- associated lesions, 30.0% of HPV positive samples harbored high-risk types, while in preneoplastic lesions the value rose to 59.9%. In cancer lesions, HPV detection in verrucous carcinoma was 88.9% and in squamous cell carcinoma 43.8%, with high-risk type rates of 75.5% and 85.6%, respectively. The high HPV frequency detected in preneoplastic and neoplastic lesions supports an HPV etiological role in at least a subset of oral cancers.

Human papillomavirus in oral lesions / Virus papiloma humano en lesiones orales

Growing evidence suggests a role for human papillomavirus (HPV) in oral cancer; however its involvement is still controversial. This study evaluates the frequency of HPV DNA in a variety of oral lesions in patients from Argentina. A total of 77 oral tissue samples from 66 patients were selected (cases); the clinical-histopathological diagnoses corresponded to: 11 HPV- associated benign lesions, 8 non-HPV associated benign lesions, 33 premalignant lesions and 25 cancers. Sixty exfoliated cell samples from normal oral mucosa were used as controls. HPV detection and typing were performed by polymerase chain reaction (PCR) using primers MY09, 11, combined with RFLP or alternatively PCR using primers GP5+, 6+ combined with dot blot hybridization. HPV was detected in 91.0% of HPV- associated benign lesions, 14.3% of non-HPV associated benign lesions, 51.5% of preneoplasias and 60.0% of cancers. No control sample tested HPV positive. In benign HPV- associated lesions, 30.0% of HPV positive samples harbored high-risk types, while in preneoplastic lesions the value rose to 59.9%. In cancer lesions, HPV detection in verrucous carcinoma was 88.9% and in squamous cell carcinoma 43.8%, with high-risk type rates of 75.5% and 85.6%, respectively. The high HPV frequency detected in preneoplastic and neoplastic lesions supports an HPV etiological role in at least a subset of oral cancers.

Crecientes evidencias sugieren que el virus Papiloma humano (HPV) tiene un rol en el cáncer oral; sin embargo su participación es todavía controvertida. Este estudio evalúa la frecuencia de ADN de HPV en una variedad de lesiones orales de pacientes de Argentina. Se seleccionaron 77 muestras de tejido oral de 66 pacientes (casos); el diagnóstico histo-patológico correspondió a: 11 lesiones benignas asociadas a HPV, 8 lesiones benignas no asociadas a HPV, 33 lesiones premalignas y 25 cánceres. Como controles se usaron 60 muestras de células exfoliadas de mucosa oral normal. La detección y tipificación de HPV se realizó por PCR empleando los primers MY09,11, seguida de RFLP, o PCR usando los primers GP5+, 6+ seguida de hibridación en dot blot. HPV fue detectado en 91% de las lesiones benignas asociadas a HPV, 14.3% de las lesiones benignas no asociadas, 51.5% de preneoplasias y 60% de cánceres. Ninguna muestra control resultó HPV positiva. En las lesiones benignas, 30% de las muestras HPV positivas correspondieron a tipos de alto riesgo, mientras que en las lesiones preneoplásicas la positividad ascendió a 59.9%. En cánceres, la detección de HPV en carcinomas verrugosos fue 88.9% y en carcinomas escamosos 43.8%, con 75.5% y 85.6% de tipos virales de alto riesgo, respectivamente. La alta frecuencia de HPV detectada en lesiones preneoplásicas y cánceres apoya un rol etiológico del HPV en, al menos, un subgrupo de cánceres orales.

Human papillomavirus in oral lesions / Virus papiloma humano en lesiones orales

Growing evidence suggests a role for human papillomavirus (HPV) in oral cancer; however its involvement is still controversial. This study evaluates the frequency of HPV DNA in a variety of oral lesions in patients from Argentina. A total of 77 oral tissue samples from 66 patients were selected (cases); the clinical-histopathological diagnoses corresponded to: 11 HPV- associated benign lesions, 8 non-HPV associated benign lesions, 33 premalignant lesions and 25 cancers. Sixty exfoliated cell samples from normal oral mucosa were used as controls. HPV detection and typing were performed by polymerase chain reaction (PCR) using primers MY09, 11, combined with RFLP or alternatively PCR using primers GP5+, 6+ combined with dot blot hybridization. HPV was detected in 91.0% of HPV- associated benign lesions, 14.3% of non-HPV associated benign lesions, 51.5% of preneoplasias and 60.0% of cancers. No control sample tested HPV positive. In benign HPV- associated lesions, 30.0% of HPV positive samples harbored high-risk types, while in preneoplastic lesions the value rose to 59.9%. In cancer lesions, HPV detection in verrucous carcinoma was 88.9% and in squamous cell carcinoma 43.8%, with high-risk type rates of 75.5% and 85.6%, respectively. The high HPV frequency detected in preneoplastic and neoplastic lesions supports an HPV etiological role in at least a subset of oral cancers.(AU)

Crecientes evidencias sugieren que el virus Papiloma humano (HPV) tiene un rol en el cáncer oral; sin embargo su participación es todavía controvertida. Este estudio evalúa la frecuencia de ADN de HPV en una variedad de lesiones orales de pacientes de Argentina. Se seleccionaron 77 muestras de tejido oral de 66 pacientes (casos); el diagnóstico histo-patológico correspondió a: 11 lesiones benignas asociadas a HPV, 8 lesiones benignas no asociadas a HPV, 33 lesiones premalignas y 25 cánceres. Como controles se usaron 60 muestras de células exfoliadas de mucosa oral normal. La detección y tipificación de HPV se realizó por PCR empleando los primers MY09,11, seguida de RFLP, o PCR usando los primers GP5+, 6+ seguida de hibridación en dot blot. HPV fue detectado en 91% de las lesiones benignas asociadas a HPV, 14.3% de las lesiones benignas no asociadas, 51.5% de preneoplasias y 60% de cánceres. Ninguna muestra control resultó HPV positiva. En las lesiones benignas, 30% de las muestras HPV positivas correspondieron a tipos de alto riesgo, mientras que en las lesiones preneoplásicas la positividad ascendió a 59.9%. En cánceres, la detección de HPV en carcinomas verrugosos fue 88.9% y en carcinomas escamosos 43.8%, con 75.5% y 85.6% de tipos virales de alto riesgo, respectivamente. La alta frecuencia de HPV detectada en lesiones preneoplásicas y cánceres apoya un rol etiológico del HPV en, al menos, un subgrupo de cánceres orales.(AU)