Andrés Castillo

Human papillomavirus detected in female breast carcinomas in Japan

To investigate the aetiological role of human papillomavirus (HPV) in breast cancer, we examined the presence, genotype, viral load, and physical status of HPV in 124 Japanese female patients with breast carcinoma. Human papillomavirus presence was examined by PCR using SPF10 primers, and primer sets targeting the E6 region of HPV-16, -18, and -33. The INNO-LiPA HPV genotyping kit was used to determine genotype. Human papillomavirus DNA was detected in 26 (21%) breast carcinomas. The most frequently detected HPV genotype was HPV-16 (92%), followed by HPV-6 (46%), HPV-18 (12%), and HPV-33 (4%). In 11 normal epithelium specimens adjacent to 11 HPV-16-positive carcinomas, 7 were HPV-16-positive. However, none of the normal breast tissue specimens adjacent to HPV-negative breast carcinomas were HPV-positive. The real-time PCR analysis suggested the presence of integrated form of viral DNA in all HPV-16-positive samples, and estimated viral load was low with a geometric mean of 5.4 copies per 104 cells. In conclusion, although HPV DNA was detected in 26 (21%) breast carcinomas and, in all HPV-16-positive cases, the HPV genome was considered integrated into the host genome, their low viral loads suggest it is unlikely that integrated HPV is aetiologically involved in the development of Japanese breast carcinomas that we examined.

Human papillomavirus in high- and low-risk areas of oesophageal squamous cell carcinoma in China

To examine the potential roles of human papillomavirus (HPV) in oesophageal squamous cell carcinoma (ESCC) development, we examined the presence of HPV DNA in paraffin-embedded ESCC tissues collected from two areas with different ESCC incidence rates in China, that is, Gansu (n=26) and Shandong (n=33), using PCR with SPF10 primers, or PCR with GP5+/GP6+ primers combined with Southern blot hybridisation. HPV genotype was determined by the INNO-LiPA HPV genotyping kit. HPV DNA was detected in 17 cases (65%) in Gansu, where ESCC incidence is much higher than in Shandong, where HPV was positive in two samples (6%). HPV genotypes 16 and 18 were detected in 79 and 16% of HPV-positive samples, respectively. Real-time PCR analysis suggested the presence of integrated form of HPV DNA in all the HPV-16-positive samples, but its viral load was estimated to be only <1–2 copies cell−1. We could not detect HPV 16/18 E6 protein expression by immunostaining in any of the HPV-16-positive samples. Neither p16INK4a nor p53 expression was related to HPV presence in ESCCs. Further studies seem warranted to examine the possible aetiological roles of HPV in ESCC.

Human papillomavirus-16 is integrated in lung carcinomas: a study in Chile

The human papillomavirus (HPV) was detected in 20 (29%) out of 69 lung carcinomas (LCs) in Chile, by PCR and Southern blot, and was more frequently detected in squamous cell carcinoma (SQC) than in adenocarcinomas (46 vs 9%, P=0.001). HPV-16, positive in 11 cases, was the most frequently detected HPV genotype determined by DNA sequencing. HPV-16 E2/E6 ratio, estimated from real-time PCR analysis, was much lower than the unity, suggesting that at least a partial HPV-16 genome was integrated in all but one HPV-16-positive SQCs. The remaining one case was suspected to have only episomal HPV-16. Although the viral load was low in most of the LCs, a case showed the HPV-16 copy number as high as 8479 per nanogram DNA, which was even a few times higher than the minimum viral load of seven cervical carcinomas (observed viral load: 3356–609 392 per nanogram DNA). The expression of the HPV-16/18 E6 protein was found in only two HPV-16-positive SQCs (13%) but not in the case with the highest viral load. Although the viral load was in general very low and HPV E6 expression is none or weak, further studies seem warranted to examine aetiological involvement of high-risk HPV in lung carcinogenesis.

Neonatal and pediatric extracorporeal membrane oxygenation in developing Latin American countries

Objective To review the principles of neonatal-pediatric extracorporeal membrane oxygenation therapy, prognosis, and its establishment in limited resource-limited countries in Latino America.

Human papillomavirus in upper digestive tract tumors from three countries

AIM To clarify human papillomavirus (HPV) involvement in carcinogenesis of the upper digestive tract of virological and pathological analyses. METHODS The present study examined the presence of HPV in squamous cell carcinomas of the oral cavity (n = 71), and esophagus (n = 166) collected from Japan, Pakistan and Colombia, with different HPV exposure risk and genetic backgrounds. The viral load and physical status of HPV16 and HPV16-E6 variants were examined. Comparison of p53 and p16(INK4a) expression in HPV-positive and HPV-negative cases was also made. RESULTS HPV16 was found in 39 (55%) oral carcinomas (OCs) and 24 (14%) esophageal carcinomas (ECs). This site-specific difference in HPV detection between OCs and ECs was statistically significant (P < 0.001). There was a significant difference in the geographical distribution of HPV16-E6 variants. Multiple infections of different HPV types were found in 13 ECs, but multiple infections were not found in OCs. This difference was statistically significant (P = 0.001). The geometric means (95% confidence interval) of HPV16 viral load in OCs and ECs were 0.06 (0.02-0.18) and 0.12 (0.05-0.27) copies per cell, respectively. The expression of p16(INK4a) proteins was increased by the presence of HPV in ECs (53% and 33% in HPV-positive and -negative ECs, respectively; P = 0.036), and the high-risk type of the HPV genome was not detected in surrounding normal esophageal mucosa of HPV-positive ECs. CONCLUSION Based on our results, we cannot deny the possibility of HPV16 involvement in the carcinogenesis of the esophagus.

Human papillomavirus-16 presence and physical status in lung carcinomas from Asia

BackgroundAlthough human papillomavirus (HPV) genome has been detected in lung cancer, its prevalence is highly variable around the world. Higher frequencies have been reported in far-east Asian countries, when compared with European countries. The present study analysed the HPV-16 presence in 60 lung carcinomas from the Asian countries China, Pakistan and Papua New Guinea.ResultsHPV-16 was present in 8/59 (13%) samples. According to histological type, HPV-16 was detected in 8/18 (44%) squamous cell carcinomas (SQCs), which were mainly from Pakistan; 0/38 (0%) adenocarcinomas (ACs), which were mainly from China; and in 0/4 (0%) small cell carcinomas (SCLCs). The observed histological difference was statistically significant (p < 0.001). HPV-16 viral load was also determined using real-time polymerase chain reaction (qRT-PCR); it ranged between 411 to 2345 copies/100 ng of genomic DNA. HPV-16 genome was found integrated into the host genome in every HPV-16 positive carcinoma.ConclusionThese results support the notion that HPV-16 infection is highly associated with SQCs in Pakistan. Our results show a frequent HPV-16 integration in SQCs, although the low viral load casts doubt respect a direct etiological role of HPV in lung carcinomas from Asia. Additional HPV-16 characterization is necessary to establish a direct or indirect etiological role of HPV in this malignancy.

Impact of oxidative stress during pregnancy on fetal epigenetic patterns and early origin of vascular diseases

Epidemiological studies have led scientists to postulate the developmental origins of health and disease hypothesis for noncommunicable diseases such as diabetes, cardiovascular diseases, hypertension, and obesity. However, the cellular and molecular mechanisms involved in the development of these diseases are not well understood. In various animal models, it has been observed that oxidative stress during pregnancy is associated with the early development of endothelial dysfunction in offspring. This phenomenon suggests that endothelial dysfunction may initiate in the uterus and could lead to increased risk of cardiovascular disease later in life. Currently, it is known that many of the fetal adaptive responses to environmental factors are mediated by epigenetic changes in the genome, especially by the degree of methylation in cytosines in the promoter regions of genes. These findings suggest that the establishment of a particular epigenetic pattern in the genome may be generated by oxidative stress.

Survival of Newborn Infants With Severe Respiratory Failure Before and After Establishing an Extracorporeal Membrane Oxygenation Program

Background: Severe hypoxic respiratory failure is a leading cause of neonatal mortality in Chile. Extracorporeal membrane oxygenation improves survival in neonates with hypoxic respiratory failure. Objective: To determine the impact of the establishment of a Neonatal Extracorporeal Membrane Oxygenation Program on the outcome of newborns with severe hypoxic respiratory failure in a developing country. Design/Patients: Data of newborns (birthweight > 2,000 g and gestational age ≥ 35 wk) with hypoxic respiratory failure and oxygenation index greater than 25 were compared before and after extracorporeal membrane oxygenation was available. Extracorporeal membrane oxygenation was initiated in infants with refractory hypoxic respiratory failure who failed to respond to inhaled nitric oxide/high-frequency oscillatory ventilation. Main Results: Data from 259 infants were analyzed; 100 born in the pre-extracorporeal membrane oxygenation period and 159 born after the extracorporeal membrane oxygenation program was established. Patients were similar in terms of risk factors for death for both periods except for a higher oxygenation index and a greater proportion of outborn infants during the extracorporeal membrane oxygenation period. Survival significantly increased from 72% before extracorporeal membrane oxygenation to 89% during the extracorporeal membrane oxygenation period (p < 0.01). During the extracorporeal membrane oxygenation period, 98 of 159 patients (62%) with hypoxic respiratory failure were rescued using inhaled nitric oxide/high-frequency oscillatory ventilation, whereas 61 (38%) did not improve; 52 of these 61 neonates were placed on extracorporeal membrane oxygenation. Extracorporeal membrane oxygenation survival rate to discharge was 85%. After adjusting for potential confounders, the severity of the pretreatment oxygenation index, a late arrival to the referral center, the presence of a pneumothorax, and the diagnosis of a diaphragmatic hernia were significantly associated with the need for extracorporeal membrane oxygenation or death. Conclusions: The establishment of an extracorporeal membrane oxygenation program was associated with a significant increase in the survival of newborns more than or equal to 35 weeks old with severe hypoxic respiratory failure.

Relationship between maternal and newborn endothelial function and oxidative stress

To evaluate the Relationship between maternal and newborn endothelial function and oxidative stress.

Envelope Sequence Variation and Phylogenetic Relations of Human T Cell Lymphotropic Virus Type 1 from Endemic Areas of Colombia

The HTLV-1 envelope gene of 12 TSP/HAM patients from two endemic areas of southwest Colombia (Tumaco and Buenaventura) was amplified by nested PCR, sequenced, and compared with previously reported HTLV-1 envelope sequences from isolates worldwide. In general, the sequence divergences among all Colombian samples ranged from 0.1 to 1.6%. Some amino acid substitutions, referring to the ATK-1 prototype strain in the surface domain gp46 and in p21, were highly prevalent in southwest Colombia, suggesting a geographical clustering of mutations in the envelope gene. The phylogenetic analysis showed that the Colombian isolates belong to the HTLV-1a lineage with minor subgroups. The genetic distance between Colombian and Japanese isolates ranged from 0.1 to 1.8%; in comparison, the genetic distance between Colombian and Caribbean isolates ranged from 0.4 to 2.2%. Our results strongly suggest that the actual quasispecies populations in southwest Colombia have been generated by separate, differently timed introductions of virus.