High-dose versus weekly cisplatin definitive chemoradiotherapy for HPV-related oropharyngeal squamous cell carcinoma of the head and neck.

OBJECTIVES: To compare the outcomes and toxicity of high-dose cisplatin (HDC) versus weekly cisplatin (WC) definitive chemoradiotherapy (CRT) for patients with human papillomavirus (HPV) related oropharyngeal squamous cell carcinoma (SCCOPx). METHODS: All patients with p16 positive SCCOPx treated with definitive CRT with cisplatin between 2010 and 2014 at a single institution were retrospectively reviewed. CTCAE v 4.03 toxicity criteria were used. The Kaplan-Meier method was used to estimate event-free survival (EFS) and the overall survival (OS). RESULTS: Of the 55 patients included, 22 were patients treated with HDC at dose of 100mg/m2 on days 1 and 22; and the remaining 33 patients were treated with WC at 40mg/m2. Both cohorts received a median total dose of cisplatin of 200mg/m2. At median follow-up of 31months, there was one local failure and no distant failures in the HDC cohort. In the WC group, there were 6 total failures (2 local, 4 distant). Estimated 2-year EFS was better in HDC cohort as compared to WC (96% vs. 75%; p=0.04). There was no significant difference in 2-year OS (95% vs. 94%; p=0.40). Weight loss, gastric tube dependence at six months, acute renal injury and grade 3 or 4 hematological toxicity were all similar between both groups. CONCLUSIONS: HPV-related SCCOPx treated with definitive CRT with either HDC or WC had similar toxicity profile. HDC had better EFS when compared with WC and this seems to be driven by increased distant failure rates, although the OS was similar.

Human papillomavirus E7 serology and association with p16 immunohistochemistry in squamous cell carcinoma of the head and neck.

BACKGROUND: Human papillomavirus (HPV)-positive oropharyngeal cancer is associated with improved survival and treatment response as compared to HPV-negative cancers. P16 overexpression is widely accepted as a surrogate marker for HPV positivity. METHODS: A total of 92 serum samples from 75 head and neck squamous cell carcinoma (HNSCC) patients were examined for HPV16 and 18 E7 antibodies by ELISA. Available tissue was tested for HPV-DNA by PCR, and p16 immunohistochemistry was obtained from a deidentified database. RESULTS: Of 75 HNSCC patients, 25 were HPV E7 seropositive. Seropositivity was strongly associated with cancers of the oropharynx, and correlated with positive p16 immunohistochemistry (IHC) and HPV-DNA. Post-treatment serum was available in a limited subset of patients, revealing a decrease in antibody titers following response to treatment. CONCLUSIONS: HPV E7 seropositivity correlated with positive tumor HPV-DNA and p16 expression, and was strongly associated with cancers of the oropharynx. E7 serology warrants further study as a potential biomarker in HPV-positive HNSCC.

High level of molecular and phenotypic biodiversity in Jatropha curcas from Central America compared to Africa, Asia and South America.

BACKGROUND: The main bottleneck to elevate jatropha (Jatropha curcas L.) from a wild species to a profitable biodiesel crop is the low genetic and phenotypic variation found in different regions of the world, hampering efficient plant breeding for productivity traits. In this study, 182 accessions from Asia (91), Africa (35), South America (9) and Central America (47) were evaluated at genetic and phenotypic level to find genetic variation and important traits for oilseed production. RESULTS: Genetic variation was assessed with SSR (Simple Sequence Repeat), TRAP (Target Region Amplification Polymorphism) and AFLP (Amplified fragment length polymorphism) techniques. Phenotypic variation included seed morphological characteristics, seed oil content and fatty acid composition and early growth traits. Jaccard's similarity and cluster analysis by UPGM (Unweighted Paired Group Method) with arithmetic mean and PCA (Principle Component Analysis) indicated higher variability in Central American accessions compared to Asian, African and South American accessions. Polymorphism Information Content (PIC) values ranged from 0 to 0.65. In the set of Central American accessions. PIC values were higher than in other regions. Accessions from the Central American population contain alleles that were not found in the accessions from other populations. Analysis of Molecular Variance (AMOVA; P < 0.0001) indicated high genetic variation within regions (81.7%) and low variation across regions (18.3%). A high level of genetic variation was found on early growth traits and on components of the relative growth rate (specific leaf area, leaf weight, leaf weight ratio and net assimilation rate) as indicated by significant differences between accessions and by the high heritability values (50-88%). The fatty acid composition of jatropha oil significantly differed (P < 0.05) between regions. CONCLUSIONS: The pool of Central American accessions showed very large genetic variation as assessed by DNA-marker variation compared to accessions from other regions. Central American accessions also showed the highest phenotypic variation and should be considered as the most important source for plant breeding. Some variation in early growth traits was found within a group of accessions from Asia and Africa, while these accessions did not differ in a single DNA-marker, possibly indicating epigenetic variation.