Immune status does not predict high-risk HPV in anal condyloma.

BACKGROUND: More than 90% of anal condyloma is attributed to nonhigh risk strains of human papillomavirus (HPV), thus patients with anal condyloma do not necessarily undergo HPV serotyping unless they are immunocompromised (IC). We hypothesized that IC patients with anal condyloma have a higher risk of high-risk HPV and dysplasia than nonimmunocompromised (NIC) patients. METHODS: We performed a retrospective chart review of patients who underwent surgical treatment by a single surgeon for anal condyloma from 1/2000 to 1/2012. HPV serotyping was performed on all patient samples. We compared incidence of high-risk HPV and dysplasia in condyloma specimens from IC and NIC patients. RESULTS: High-risk HPV was identified in 14 specimens with serotypes 16, 18, 31, 33, 51, 52, and 67. Twenty-two cases (18.3%) had dysplasia. Invasive carcinoma was identified in one IC patient. The prevalence of dysplasia or high-risk HPV was not significantly different between IC and NIC groups. High-risk HPV was a significant independent predictor of dysplasia (odds ratio [OR] = 5.2; 95% CI = 1.24-21.62). Immune status, however, was not a significant predictor of high-risk HPV (OR = 1.11; 95% CI = 0.16-5.12) nor dysplasia (OR = 0.27; 95% CI = 0.037-1.17). CONCLUSIONS: IC patients did not have a significantly higher prevalence or risk of high-risk HPV or dysplasia in our study. HPV typing of all condylomata, regardless of immune status, should be considered as it may help predict risk of neoplastic transformation or identify NIC patients with an increased risk of developing anal intraepithelial neoplasia.

A common variant in MTHFR influences response to chemoradiotherapy and recurrence of rectal cancer.

An important determinant of the pathogenesis and prognosis of various diseases is inherited genetic variation. Single-nucleotide polymorphisms (SNPs), variations at a single base position, have been identified in both protein-coding and noncoding DNA sequences, but the vast majority of millions of those variants are far from being functionally understood. Here we show that a common variant in the gene MTHFR [rs1801133 (C>T)] not only influences response to neoadjuvant chemoradiotherapy in patients with rectal cancer, but it also influences recurrence of the disease itself. More specifically, patients with the homozygous ancestral (wild type) genotype (C/C) were 2.91 times more likely (291% increased benefit) to respond to neoadjuvant chemoradiotherapy {95% CI: [1.23, 6.89]; P=0.0150} and 3.25 times more likely (325% increased benefit) not to experience recurrence of the disease {95% CI: [1.37, 7.72]; P=0.0079} than patients with either the heterozygous (C/T) or the homozygous mutation (T/T) genotype. These results identify MTHFR as an important genetic marker and open up new, pharmacogenomic strategies in the treatment and management of rectal cancer.

Systematic Review of Candidate Single-nucleotide Polymorphisms as Biomarkers for Responsiveness to Neoadjuvant Chemoradiation for Rectal Cancer.

BACKGROUND/AIM: Treatment of rectal cancer has improved significantly with the addition of neoadjuvant chemoradiation. Certain patients have experienced a complete pathological response to chemoradiation, as observed in surgically resected tissue samples, thus calling into question the necessity of radical surgery in this population of patients. Pharmacogenetic studies now implicate the role that genetic biomarkers, such as single nucleotide polymorphisms, play in an individual's response to chemoradiation. The aim of this review was to provide a comprehensive evaluation of a group of candidate single nucleotide polymorphisms associated with chemoradiotherapy response and an assessment of techniques that can be used to easily identify the presence of these single nucleotide polymorphisms in patient samples. MATERIALS AND METHODS: Relevant primary research articles were identified in the Medline Database from January 1, 2006 to May 31, 2012. We included nine relevant articles addressing the correlation between six candidate single nucleotide polymorphisms and one candidate variable number tandem repeat in six genes, namely thymidylate synthase, epidermal growth factor, epidermal growth factor receptor, superoxide dismutase 2, interleukin-13, and cyclin D1, with tumor down-staging and patient survival after neoadjuvant chemotherapy or chemoradiotherapy. RESULTS: Specific alleles of each of the candidate single nucleotide polymorphisms were significantly associated with either a major response in tumor down-staging or a minor to non-existent response following neoadjuvant chemotherapy, individually or in combination with other single nucleotide polymorphisms. However, studies present conflicting results regarding the effect of certain candidate single nucleotide polymorphisms on tumor down-staging. CONCLUSION: Through further research into candidate single nucleotide polymorphisms and potential identification of other polymorphisms, clinicians may be able to create individualized treatment plans in accordance with the genotype of individual patients with rectal cancer, in order to reduce morbidity and mortality.

Oxidative Stress Increases Surface Toll-Like Receptor 4 Expression in Murine Macrophages Via Ceramide Generation.

Multiorgan failure is a major cause of late mortality following trauma. Oxidative stress generated during shock/resuscitation contributes to tissue injury by priming the immune system for an exaggerated response to subsequent inflammatory stimuli, such as lipopolysaccharide (LPS). We recently reported that oxidative stress causes rapid recruitment of the LPS receptor Toll-like receptor 4 (TLR4) to membrane lipid rafts, thus increasing LPS responsiveness and cellular priming. We hypothesized that activation of Src family kinases by oxidants might contribute to these events. We utilized microscopy, flow cytometry, Western blotting, and thin-layer chromatography methods. Using hydrogen peroxide in vitro and hemorrhagic shock/resuscitation in vivo, oxidant-induced TLR4 translocation in macrophages occurred in an Src-dependent manner. Approaches supporting this conclusion included pharmacologic inhibition of the Src family kinases by PP2, Src inhibition by a molecular approach of cell transfection with Csk, and genetic inhibition of all Src kinases relevant to the monocyte/macrophage lineage in hckfgrlyn triple knockout mice. To evaluate the upstream molecules involved in Src activation, we evaluated the ability of oxidative stress to activate the bioactive lipid molecule ceramide. Oxidants induced ceramide generation in macrophages both in vitro and in vivo, an effect that appears to be due to activation of the acid sphingomyelinase. Using pharmacological approaches, ceramide was shown to be both necessary and sufficient to mediate TLR4 translocation to the plasma membrane in an Src-dependent manner. This study identifies a hierarchy of signaling molecules following oxidative stress that might represent novel targets for therapy in critical illness and organ injury.

Adenocarcinoma of the rectum in patients under age 40 is increasing: impact of signet-ring cell histology.

BACKGROUND: Overall, the incidence of colorectal cancer appears to be stable or diminishing. However, based on our practice pattern, we observed that the incidence of rectal cancer in patients under 40 is increasing and may be associated with a prominence of signet-ring cell histology. OBJECTIVE: The aim of this study was to verify the rising trend in rectal cancer in patients under 40 and describe the histology prominent in that cohort. DESIGN: This is a retrospective cohort study. SETTING AND PATIENTS: We performed a retrospective cohort study of all patients diagnosed with rectal adenocarcinoma from 1980 to 2010 using the Surveillance, Epidemiology, and End Results cancer registry. MAIN OUTCOME MEASURES: Rectal cancer incidence, histology, and associated staging characteristics were the primary outcomes measured. RESULTS: Although the incidence of rectal cancer for all ages remained stable from 1980 to 2010, we observed an annual percent change of +3.6% in the incidence of rectal cancer in patients under 40. The prevalence of signet cell histology in patients under 40 was significantly greater than in patients over 40 (3% vs 0.87%, p < 0.01). A multivariate regression analysis revealed an adjusted odds ratio of 3.6 (95% CI, 2.6-5.1) for signet cell histology in rectal adenocarcinoma under age 40. Signet cell histology was also significantly associated with a more advanced stage at presentation, poorly differentiated tumor grade, and worse prognosis compared with mucinous and nonmucinous rectal adenocarcinoma. LIMITATIONS: The study was limited by its retrospective nature and the information available in the Surveillance, Epidemiology, and End Results database. CONCLUSIONS: Despite a stable incidence of rectal cancer for all ages, the incidence in patients under 40 has quadrupled since 1980, and cancers in this group are 3.6 times more likely to have signet cell histology. Given the worse outcomes associated with signet cell histology, these data highlight a need for thorough evaluation of young patients with rectal symptoms.

Enhanced primer selection and synthetic amplicon templates optimize high-resolution melting analysis of single-nucleotide polymorphisms in a large population.

AIMS: High-resolution melting (HRM) screening and scanning for single-nucleotide polymorphisms (SNPs) afford the advantages of a quicker, less expensive, and less demanding option compared to other methods for sequence analysis. The evaluation of large populations of patients for multiple SNPs in a high-throughput manner is the next phase in individualized medicine. RESULTS: We demonstrated that Tm profiles can be generated from gDNA samples that clearly differentiate homozygous ancestral, homozygous SNP, and heterozygous genotypes, while identifying samples of unique outcome without the cumbersome processes of normalization, temperature shifting, and difference plot generation. CONCLUSIONS: Through expanded primer selection criterion and inclusion of a cloning fragment length double-stranded DNA sequence-specific control template, we are now able to generate additional data via HRM melt domains that are greatly simplified, while considering both the peak melt temperature and profile.

Hypertonic saline resuscitation from hemorrhagic shock does not impair the neutrophil response to intraabdominal infection.

BACKGROUND: Hypertonic saline (HTS) has been proposed as a resuscitation strategy following trauma based on its ability to prevent organ dysfunction by exerting immunosuppressive effects on inflammatory cells, including neutrophils. Because these cells are central to the innate response to bacteria, we hypothesized that hypertonic treatment for hemorrhagic shock might alter the host response to bacterial contamination of the peritoneal cavity and therefore render the host more susceptible to invasive infection. METHODS: Male Sprague-Dawley rats were subjected to hemorrhagic shock and resuscitated with either lactated Ringer solution (RL) or HTS. After intraperitoneal injection of feces, Escherichia coli, or lipopolysaccharide, peritoneal neutrophil accumulation and bacterial clearance were studied. In some studies, lipopolysaccharide as an inflammatory stimulus was injected into both the peritoneal cavity and the lungs. RESULTS: Peritoneal neutrophil accumulation in response to each of the stimuli did not differ between RL- and HTS-resuscitated animals. Whereas emigration into the peritoneum activated neutrophils, there was no difference between resuscitation strategies, consistent with the finding that bacterial clearance did not differ between groups. Although peritoneal neutrophil sequestration was unaffected by resuscitation type, HTS still was able to prevent lung neutrophil accumulation compared to RL treatment. CONCLUSIONS: HTS resuscitation did not impair the host response to bacterial contamination of the peritoneal cavity. However, the ability of HTS to prevent lung neutrophil accumulation in this setting persisted. These findings suggest that peritoneal bacterial contamination should not be considered a contraindication to the use of HTS in the trauma setting associated with hemorrhagic shock.

Oxidative stress generated by hemorrhagic shock recruits Toll-like receptor 4 to the plasma membrane in macrophages.

Oxidative stress generated by ischemia/reperfusion is known to prime inflammatory cells for increased responsiveness to subsequent stimuli, such as lipopolysaccharide (LPS). The mechanism(s) underlying this effect remains poorly elucidated. These studies show that alveolar macrophages recovered from rodents subjected to hemorrhagic shock/resuscitation expressed increased surface levels of Toll-like receptor 4 (TLR4), an effect inhibited by adding the antioxidant N-acetylcysteine to the resuscitation fluid. Consistent with a role for oxidative stress in this effect, in vitro H2O2 treatment of RAW 264.7 macrophages similarly caused an increase in surface TLR4. The H2O2-induced increase in surface TLR4 was prevented by depleting intracellular calcium or disrupting the cytoskeleton, suggesting the involvement of receptor exocytosis. Further, fluorescent resonance energy transfer between TLR4 and the raft marker GM1 as well as biochemical analysis of the raft components demonstrated that oxidative stress redistributes TLR4 to lipid rafts in the plasma membrane. Preventing the oxidant-induced movement of TLR4 to lipid rafts using methyl-beta-cyclodextrin precluded the increased responsiveness of cells to LPS after H2O2 treatment. Collectively, these studies suggest a novel mechanism whereby oxidative stress might prime the responsiveness of cells of the innate immune system.