Venous thromboembolism after inpatient surgery in administrative data vs NSQIP: a multi-institutional study

Previous studies have documented significant differences between administrative data and registry data in the determination of postoperative venous thromboembolism (VTE). The goal of this study was to characterize the discordance between administrative and registry data in the determination of postoperative VTE.This study was performed using data from the American College of Surgeons NSQIP merged with administrative data from 8 different hospitals (5 different medical centers) between 2013 and 2015. Occurrences of postoperative vein thrombosis (VT) and pulmonary embolism (PE) as ascertained by administrative data and NSQIP data were compared. In each situation where the 2 sources disagreed (discordance), a 2-clinician chart review was performed to characterize the reasons for discordance.The cohort used for analysis included 43,336 patients, of which 53.3% were female and the mean age was 59.5 years. Concordance between administrative and NSQIP data was worse for VT (κ 0.57; 95% CI 0.51 to 0.62) than for PE (κ 0.83; 95% CI 0.78 to 0.89). A total of 136 cases of discordance were noted in the assessment of VT; of these, 50 (37%) were explained by differences in the criteria used by administrative vs NSQIP systems. In the assessment of postoperative PE, administrative data had a higher accuracy than NSQIP data (odds ratio for accuracy 2.86; 95% CI 1.11 to 7.14) when compared with the 2-clinician chart review.This study identifies significant problems in ability of both NSQIP and administrative data to assess postoperative VT/PE. Administrative data functioned more accurately than NSQIP data in the identification of postoperative PE. The mechanisms used to translate VTE measurement into quality improvement should be standardized and improved

HIV-1 Protease Inhibitors Slow HPV16-Driven Cell Proliferation through Targeted Depletion of Viral E6 and E7 Oncoproteins

High-risk human papillomavirus strain 16 (HPV16) causes oral and anogenital cancers through the activities of two viral oncoproteins, E6 and E7, that dysregulate the host p53 and pRb tumor suppressor pathways, respectively. The maintenance of HPV16-positive cancers requires constitutive expression of E6 and E7. Therefore, inactivating these proteins could provide the basis for an anticancer therapy. Herein we demonstrate that a subset of aspartyl protease inhibitor drugs currently used to treat HIV/AIDS cause marked reductions in HPV16 E6 and E7 protein levels using two independent cell culture models: HPV16-transformed CaSki cervical cancer cells and NIKS16 organotypic raft cultures (a 3-D HPV16-positive model of epithelial pre-cancer). Treatment of CaSki cells with some (lopinavir, ritonavir, nelfinavir, and saquinavir) but not other (indinavir and atazanavir) protease inhibitors reduced E6 and E7 protein levels, correlating with increased p53 protein levels and decreased cell viability. Long-term (>7 day) treatment of HPV16-positive NIKS16 raft cultures with saquinavir caused epithelial atrophy with no discernible effects on HPV-negative rafts, demonstrating selectivity. Saquinavir also reduced HPV16′s effects on markers of the cellular autophagy pathway in NIKS16 rafts, a hallmark of HPV-driven pre-cancers. Taken together, these data suggest HIV-1 protease inhibitors be studied further in the context of treating or preventing HPV16-positive cancers

Genetic inhibition of autophagy in a transgenic mouse model of anal cancer

Background: The dynamic role of autophagy in cancer development is a topic of considerable research and debate. Previously published studies have shown that anal cancer development can be promoted or prevented with the pharmacologic inhibition or induction, respectively, of autophagy in a human papillomavirus (HPV) mouse model. However, these results are confounded by the fact that the drugs utilized are known to affect other pathways besides autophagy. It has also been shown that autophagic inhibition occurs in the setting of HPV16 oncoprotein expression (E6 and E7) and correlates with increased susceptibility to anal carcinogenesis. Materials and Methods: In this study, we employed a conditional, genetic, autophagic (Atg7) knockout mouse model to determine conclusively that autophagy has a role in anal cancer development, in the absence or presence of E6 and E7. Results: In mice lacking both HPV16 oncogenes, knockout of autophagy followed by exposure to a carcinogen resulted in a tumor incidence of 40%, compared to 0% in mice treated with a carcinogen alone with an intact autophagic pathway (P = 0.007). In mice expressing either one or both HPV16 oncoproteins, the addition of genetic knockout of autophagy to carcinogen treatment did not lead to a significant difference in tumor incidence compared to carcinogen treatment alone, consistent with the ability of HPV oncogenes to inhibit autophagy in themselves. Conclusions: These results provide the first conclusive evidence for the distinct role of autophagy in anal carcinogenesis, and suggest that autophagy is a plausible target for therapies aimed at reducing anal dysplasia and anal cancer development

Dysregulation of Autophagy Contributes to Anal Carcinogenesis

<div><p>Introduction</p><p>Autophagy is an intracellular catabolic process that removes and recycles unnecessary/dysfunctional cellular components, contributing to cellular health and survival. Autophagy is a highly regulated cellular process that responds to several intracellular signals, many of which are deregulated by human papillomavirus (HPV) infection through the expression of HPV-encoded oncoproteins. This adaptive inhibitory response helps prevent viral clearance. A strong correlation remains between HPV infection and the development of squamous cell carcinoma (SCC) of the anus, particularly in HIV positive and other immunosuppressed patients. We hypothesize that autophagy is inhibited by HPV–encoded oncoproteins thereby promoting anal carcinogenesis (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0164273#pone.0164273.g001" target="_blank">Fig 1</a>).</p><p>Materials and Methods</p><p>HPV16 transgenic mice (K14E6/E7) and non-transgenic mice (FVB/N), both of which do not spontaneously develop anal tumors, were treated topically with the chemical carcinogen, 7,12-Dimethylbenz[a]anthracene (DMBA), to induce anal cancer. The anuses at different time points of treatment (5, 10, 15 and 20 weeks) were analyzed using immunofluorescence (IF) for two key autophagy marker proteins (LC3β and p62) in addition to histological grading. The anuses from the K14E6/E7 mice were also analyzed for visual evidence of autophagic activity by electron microscopy (EM). To see if there was a correlation to humans, archival anal specimens were assessed histologically for grade of dysplasia and then analyzed for LC3β and p62 protein content. To more directly examine the effect of autophagic inhibition on anal carcinogenesis, nontransgenic mice that do not develop anal cancer with DMBA treatment were treated with a known pharmacologic inhibitor of autophagy, chloroquine, and examined for tumor development and analyzed by IF for autophagic proteins.</p><p>Results</p><p>Histologically, we observed the progression of normal anoderm to invasive SCC with DMBA treatment in K14E6/E7 mice but not in nontransgenic, syngeneic FVB/N background control mice. With the development of low-grade dysplasia in the K14E6/E7 mice, there was an increase in both punctate LC3β and p62 expression while EM revealed increased autophagosomes without evidence of autophagolysosomes. These observations are consistent with autophagy being inhibited at a later stage in the autophagic process. In contrast, in high-grade dysplasia and SCC in the DMBA-treated K14E6/E7 mice, there were decreased levels of p62 with a continued increase in punctate LC3β expression by IF, while autophagolysosomes were seen on EM, consistent with the process of autophagy proceeded to completion. Similar findings, including histological grade dependent changes in LC3β and p62 expression, were noted with human samples upon analysis of IF. Finally, with pharmacologic inhibition of autophagy in DMBA-treated, nontrangenic FVB/N mice, there was a significant increase in anal cancer development similar to that observed in DMBA- treated K14E6/E7 mice.</p><p>Conclusion</p><p>Autophagic dysregulation is noted early on in HPV-associated anal carcinogenesis (low-grade dysplasia), with normalization of the autophagic process arising in late stages of HPV-associated anal carcinogenesis (high-grade dysplasia and invasive carcinoma).</p></div

Histological analysis of the anal transition zone at various time points of DMBA treatment in K14E6/E7 mice.

<p>Anal histology identified by a trained pathologist for each time point (25 mice/group) following treatment with and without DMBA (0.12μmole topically to anus weekly). There is a statiscally significant increase in anal dysplasia over the time course of DMBA treatment, with the majority of the mice at 5 and 10 weeks of DMBA treatment having low-grade dysplasia, while 75% of mice at 15 weeks. By 20 weeks of DMBA treatment 100% of K14E6/E7 mice have overt carcinoma. During this same time course none of the K14E6/E7 mice not treated with DMBA developed anal cancer.</p

Histological analysis of the anal transition zone at various time points in FVB/N mice during DMBA treatment time course.

<p>Anal histology identified by a trained pathologist for each time point (25 mice/group) following treatment with and without DMBA (0.12μmole topically to anus weekly). A) H&E staining of animals not treated with DMBA at the 5 week timepoint reveals normal epithelium. (B) Following 5 weeks of DMBA treatment, there is inflammation seen on H&E staining. (C) At 10 weeks of DMBA treatment there is histological evidence of low-grade dysplasia. (D) Low-grade dysplasia is present at 15 weeks of DMBA treatment and (E) high-grade dysplasia at 20 weeks of DMBA treatment. All images are acquired at 20x magnification.</p

LC3β and p62 immunofluorescence intensity of human anal samples based on histological classification demonstrating autophagic dysfunction, similar to K14E6/E7 mice, with the development of low-grade dysplasia that is not evident in normal or high-grade dysplasia samples.

<p>There is statistical difference in p62 expression levels between normal and LSIL and between HSIL and LSIL (p-value = 0.001). The expression levels of LC3β and p62 show similar changes as noted in K14E6/E7 mice over the time course of DMBA treatment (<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0164273#pone.0164273.g007" target="_blank">Fig 7</a>) with evidence of autophagic dysfunction in samples with low-grade dysplasia.</p

Percent Tumor Free Survival curves for FVB/N mice with and without DMBA and chloroquine treatment.

<p>The curves in black represent FVB/N mice with and without DMBA that did not receive chloroquine. The curves in red are FVB/N mice receiving chloroquine with and without DMBA. There is a statistically significant increase in the number of FVB/N mice that developed anal tumors with DMBA treatment when the mice were also treated with the late autophagic inhibitor, chloroquine. Both FVB/N mice without DMBA and with chloroquine alone did not develop anal tumors over the time course, resulting in the lines overlapping.</p