Epstein-Barr virus load in transplant patients: Early detection of post-transplant lymphoproliferative disorders / Carga de virus Epstein-Barr en pacientes trasplantados: detección temprana de desórdenes linfoproliferativos postrasplante

High levels of circulating EBV load are used as a marker of post-transplant lymphoproliferative disorders (PTLD). There is no consensus regarding the threshold level indicative of an increase in peripheral EBV DNA. The aim of the study was to clinically validate a developed EBV quantification assay for early PTLD detection. Transversal study: paired peripheral blood mononuclear cells (PBMC), plasma and oropharyngeal lymphoid tissue (OLT) from children undergoing a solid organ transplant with (n = 58) and without (n = 47) PTLD. Retrospective follow-up: 71 paired PBMC and plasma from recipients with (n = 6) and without (n = 6) PTLD history. EBV load was determined by real-time PCR. The diagnostic ability to detect all PTLD (categories 1-4), advanced PTLD (categories 2-4) or neoplastic PTLD (categories 3 and 4) was estimated by analyzing the test performance at different cut-off values or with a load variation greater than 0.5 log units. The higher diagnostic performance for identifying all, advanced or neoplastic PTLD, was achieved with cut-off values of 1.08; 1.60 and 2.47 log EBV gEq/10(5) PBMC or 2.30; 2.60; 4.47 log gEq/10(5) OLT cells, respectively. EBV DNA detection in plasma showed high specificity but low (all categories) or high (advanced/neoplastic categories) sensitivity for PTLD identification. Diagnostic performance was greater when: (1) a load variation in PBMC or plasma was identified; (2) combining the measure of EBV load in PBMC and plasma. The best diagnostic ability to identify early PTLD stages was achieved by monitoring EBV load in PBMC and plasma simultaneously; an algorithm was proposed.

La carga alta del virus Epstein-Barr se utiliza como un marcador de desórdenes linfoproliferativos postrasplante (post-transplant lymphoproliferative disorders [PTLD]). El objetivo de este estudio fue validar clínicamente un ensayo de cuantificación del virus Epstein-Barr para la detección temprana de PTLD. Se efectuó un estudio transversal en el que se analizaron muestras pareadas de células mononucleares periféricas (CMP), de plasma y de tejido linfoide orofaríngeo de niños con trasplante de órgano sólido, con PTLD (n = 58) y sin PTLD (n = 47). En el seguimiento retrospectivo se incluyeron 71 muestras pareadas de CMP y de plasma de trasplantados, con PTLD (n = 6) y sin PTLD (n = 6). La carga viral se determinó por PCR en tiempo real. Se estimó la capacidad diagnóstica para detectar PTLD (categorías: todas vs. avanzadas vs. neoplásicas) analizando diferentes valores de corte o una variación de carga mayor de 0,5 logaritmos. El mayor desempeño diagnóstico para identificar todos los PTLD, los avanzados y los neoplásicos, se obtuvo con valores de corte de 1,08; 1,60 y 2,47 log copias/10(5) en CMP y de 2,30; 2,60 y 4,48 log copias/10(5) en células de tejido linfoide orofaríngeo, respectivamente. La detección del ADN del virus Epstein-Barr en el plasma mostró una especificidad alta, pero una sensibilidad baja (todas las categorías) o alta (categorías avanzadas o neoplásicas) para identificar PTLD. Se observó el desempeño diagnóstico más alto en las siguientes condiciones: 1) al identificar una variación de carga en CMP o en plasma; 2) combinando la medición de la carga viral en CMP y en plasma. La mejor capacidad diagnóstica para identificar las etapas tempranas de los PTLD se logró mediante el seguimiento simultáneo de la carga viral en CMP y en plasma; se propone un algoritmo.

Epstein-Barr virus load in transplant patients: Early detection of post-transplant lymphoproliferative disorders.

High levels of circulating EBV load are used as a marker of post-transplant lymphoproliferative disorders (PTLD). There is no consensus regarding the threshold level indicative of an increase in peripheral EBV DNA. The aim of the study was to clinically validate a developed EBV quantification assay for early PTLD detection. Transversal study: paired peripheral blood mononuclear cells (PBMC), plasma and oropharyngeal lymphoid tissue (OLT) from children undergoing a solid organ transplant with (n=58) and without (n=47) PTLD. Retrospective follow-up: 71 paired PBMC and plasma from recipients with (n=6) and without (n=6) PTLD history. EBV load was determined by real-time PCR. The diagnostic ability to detect all PTLD (categories 1-4), advanced PTLD (categories 2-4) or neoplastic PTLD (categories 3 and 4) was estimated by analyzing the test performance at different cut-off values or with a load variation greater than 0.5log units. The higher diagnostic performance for identifying all, advanced or neoplastic PTLD, was achieved with cut-off values of 1.08; 1.60 and 2.47log EBVgEq/10(5) PBMC or 2.30; 2.60; 4.47loggEq/10(5) OLT cells, respectively. EBV DNA detection in plasma showed high specificity but low (all categories) or high (advanced/neoplastic categories) sensitivity for PTLD identification. Diagnostic performance was greater when: (1) a load variation in PBMC or plasma was identified; (2) combining the measure of EBV load in PBMC and plasma. The best diagnostic ability to identify early PTLD stages was achieved by monitoring EBV load in PBMC and plasma simultaneously; an algorithm was proposed.

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.

A semiquantitative PCR method (SQ-PCR) to measure Epstein-Barr virus (EBV) load: its application in transplant patients.

BACKGROUND: High Epstein-Barr virus load has been related to an increased risk of Posttransplant Lymphoproliferative Disorders (PTLD) in transplant recipients. OBJECTIVES: Development of a method to quantitate EBV DNA levels in peripheral blood mononuclear cells (PBMC) and evaluate its usefulness in transplant patients. STUDY DESIGN: We designed a semiquantitative nested PCR based on a limiting dilution analysis to detect high viral loads in PBMC. This method was applied to 25 healthy carriers, and 85 solid organ transplant recipients as follows: (A) 53 asymptomatic patients; (B) 24 symptomatic patients; (C) eight patients with PTLD. RESULTS: In healthy carriers the reciprocal of the limiting dilution (RLD) ranged between non-detected (ND) and 1, the median RLD was ND, which is equivalent to a viral load of <1 copy per 10(5) PBMC. In the transplant population the medians RLD (range) were: (A) asymptomatic group: ND (ND-64), median equivalent to a viral load of <1 copy per 10(5) PBMC; (B) symptomatic group: 4 (ND-256), median equivalent to a range of viral load of 4-64 copies per 10(5) PBMC. (C) PTLD group: 256 (16-16384), median equivalent to a range of viral load of 256-4096 copies per 10(5) PBMC. Statistically significant differences were found between all groups: A+B vs. C (P<0.0001); A vs. B (P<0.0001); A vs. C (P<0.0001), B vs. C (P<0.0001). We also observed a good correlation between viral loads and clinical findings in four follow-up patients. Considering the RLD=256 as a cutoff point to detect transplant patients with PTLD, resulted in sensitivity 75%, specificity 96.7%, positive predictive value 60%, negative predictive value 98.3%. CONCLUSION: This SQ-PCR method enables us to differentiate between transplant patients with and without PTLD; therefore, it could be applied as a marker for early detection of this pathology.

[Human Papilloma virus in Quechua women from Jujuy with high frequency of cervical cancer: viral types and HPV-16 variants]. / Virus papiloma humano en mujeres quechuas jujeñas con alta frecuencia de cáncer de cuello uterino. Tipos virales y variantes de HPV16.

Human Papillomaviruses (HPVs) are etiologically associated to cervical carcinoma. In order to evaluate HPV infection and its relationship with the high frequency of this neoplasia in Quechua women from Jujuy (Argentina), 271 cervical samples from preneoplastic and neoplastic lesions (biopsies) and normal controls (cytologies) were studied. Detection and typing were performed using PCR-RFLP or PCR-hybridization and the HPV-16 variability in L1 and E6 genes (by PCR-hybridization) was analysed. HPV was detected in 52% of controls, 91% of low-grade lesions, 97% of high-grade lesions and 100% of invasive carcinomas, corresponding 55% to HPV-16. HPV-16 European variants were predominant, most of them being non-prototypic strains. The high frequency of high risk infection types and the raised proportion of HPV-16 non-prototypic variants related to a greater oncogenic potential could explain, in part, the high cervical cancer frequency of this native population. These data may contribute to disease control and vaccinal formulation.

Virus papiloma humano en mujeres quechuas jujeñas con alta frecuencia de cancer de cuello uterino: tipos virales y variantes de HPV 16 / Human Papilloma virus in Quechua women from Jujuy with high frequency of cervical cancer: viral types and HPV-16 variants

Human Papillomaviruses (HPVs) are etiologically associated to cervical carcinoma. In order to evaluate HPV infection and its relationship with the high frequency of this neoplasia in Quechua women from Jujuy (Argentina), 271 cervical samples from preneoplastic and neoplastic lesions (biopsies) and normal controls (cytologies) were studied. Detection and typing were performed using PCR-RFLP or PCR-hybridization and the HPV-16 variability in L1 and E6 genes (by PCR-hybridization) was analysed. HPV was detected in 52 of controls, 91 of low-grade lesions, 97 of high-grade lesions and 100 of invasive carcinomas, corresponding 55 to HPV-16. HPV-16 European variants were predominant, most of them being non-prototypic strains. The high frequency of high risk infection types and the raised proportion of HPV-16 non-prototypic variants related to a greater oncogenic potential could explain, in part, the high cervical cancer frequency of this native population. These data may contribute to disease control and vaccinal formulation

Variantes moleculares de virus papiloma humano (HPV) tipos 16 y 18 en adenocarcinomas de cervix / Molecular variants of human papillomavirus (HPV) types 16 and 18 in adenocarcinomas of the cervix

Los virus Papiloma humano (HPV), en particular los tipos 16 y 18, son considerados carcinógenos humanos, habiéndose demostrado una asociación etiológica entre la infección con estos virus y el desarrollo del cáncer de cuello uterino. El rol viral en el carcinoma escamoso ha sido ampliamente estudiado aunque la información disponible en relación al adenocarcinoma es mucho menor, en parte debido a su baja frecuencia. En este trabajo investigamos la presencia de tipos y variantes intratípicas de HPV en adenocarcinomas de cérvix. Se incluyeron 23 biopsias de archivo, fijadas y embebidas en parafina. La detección y tipificación viral se llevó a cabo mediante PCR genérica y posterior análisis de polimorfismos conformacionales de cadena simple (SSCP). La variabilidad genética se investigó en un fragmento de 450 pb del gen L1, mediante la secuenciación directa post-PCR. Se detectaron 11 muestras positivas para HPV 16 (9 prototipos y 2 variantes: 1 europea y 1 asiática-americana), 10 para HPV 18 (9 prototipos y 1 variante europea), 1 para HPV 31 y 1 negativa. Se confirmó la asociación de HPV de alto riesgo con esta neoplasia, con una alta prevalencia (43%) de HPV 18 pero sin un predominio sobre los demás tipos virales, como fue publicado previamente. La variabilidad demostrada en epítopes de la proteína L1 originaron cambios aminoacídicos que podrían tener implicancias en la repuesta inmune y por lo tanto ser considerados en el diseño de vacunas.

Mutaciones en genes Ha-ras y p53 detectadas mediante PCR-SSCP en lesiones premalignas y malignas de cuello uterino asociadas con virus papiloma humano (HPV) / Ha-ras and p53 gene mutations scanned by PCR-SSCP in premalignant and malignant lesions of the uterine cervix associated with human papillomavirus

El objetivo del estudio fue investigar las frecuencias de virus papiloma humano (HPV) y de mutaciones en los genes Ha-ras y el supresor p53 en tumores y lesiones precursoras de cérvix. Se incluyeron en el estudio 30 carcinomas invasores (CAIN), 36 displasias severas (CIN III) y 12 tejidos normales adyacentes a los tumores (TN). Se realizó la tipificación de HPV y la búsqueda de mutaciones en los genes Ha-ras y p 53 mediante PCR-SSCP. Los CAIN fueron HPV positivos en el 93%; en el 41% se observaron mutaciones en Ha-ras y en el 17% para p53. El 80% de los CIN III fue HPV positivo, en el 18% se detectaron mutaciones en Ha-ras y en el 11% en p53. En los TN el HPV se detectó en el 17% de los casos. Todas las mutaciones fueron heterocigotas. Por otro lado, todas las muestras con mutaciones en Ha-ras resultaron HPV positivas, en cambio el 33% de los casos de p53 mutada fueron HPV negativos. El HPV 16 (44%) fue más prevalente que el HPV 18 (15%); los casos de tipo viral no determinado (18%), indicarían la circulación en nuestro país, de otros tipos distintos a los ensayados (6, 11, 16, 18, 31 y 33), variantes o infecciones mixtas. La baja frecuencia de mutaciones en el gen p53 señala que la inactivación de la proteína normal mediada por HPV tendría un rol más importante en la patogénesis del cáncer. Dado que el Ha-ras mutado se halló en lesiones premalignas, hemos especulado que podría representar un marcador temprano de progresión. Nuestros hallazgos proveen de evidencias adicionales acerca de un efecto interactivo entre los HPV de alto riesgo y de oncogenes en el desarrollo tumoral.