Short-term in vivo modifications of platelet NADPH oxidase 2 (NOX2) and prostaglandin F2α in HIV-1 patients on abacavir-based therapies

OBJECTIVES

The aim of the study was to investigate the in vivo effect of abacavir (ABC) on platelet oxidative stress.

METHODS

We performed a randomized pilot study including 39 HIV-1-infected patients, 17 on zidovudine/lamivudine (ZDV/3TC) and 22 on tenofovir/emtricitabine (TDF/FTC). Ten patients on ZDV/3TC and eight patients on TDF/FTC were randomly allocated to switching the nucleoside backbone to ABC/3TC. At baseline and after 6 months, platelet oxidative stress was assessed by platelet NADPH oxidase 2 (NOX2)-derived peptide (sNOX2-dp), a marker of NOX2 activation, and platelet prostaglandin F_2α (8-iso-PGF_2α ). Platelet activation was measured by soluble CD40L (sCD40L).

RESULTS

At baseline, no differences between ZDV/3TC or TDF/FTC recipients were found. After 6 months, patients switching from ZDV/3TC showed a decrease of sNOX2-dp (from 20.9±5.7 to 12.5±3.8 pg/ml, p=0.002) and 8-iso-PGF_2α (from 154.3±41.9 to 122.9±28.0 pmol/l, p=0.025). No effects on platelet oxidative stress biomarkers were observed in subjects from TDF/FTC, who showed a significant increase in blood glucose (p=0.043) and total cholesterol (p=0.027). ABC showed no effect on sCD40L levels in both groups.

CONCLUSIONS

ABC reduced platelet sNOX2-dp and 8-iso-PGF_2α in HIV-1 subjects switching from ZDV/3TC but not in those from TDF/FTC after 6 months. No changes in platelet activation were found in both groups.

Characterization of normal and scarred myocardium based on texture analysis of cardiac computed tomography images

An accurate detection of myocardial scar using Cardiac CT may have a strong clinical impact; however, the main drawback is the insufficient contrast to noise ratio of delayed iodine enhanced (DIE) CT images, which makes its accurate segmentation (manual as well as automatic) difficult. In this work, we investigate texture parameters applied on the different scans in order to obtain the scans and features that best differentiates normal from scarred myocardium. The experiments on 7 cases of myocarditis show the accuracy of the parameter energy in all scans, as well as the good performance of the angiographic scan (having higher spatial resolution) with different parameters for the segmentation propose. Moreover, the best performance was obtained on the baseline scan for the energy feature, with an accuracy of 94%.

Identification of High-Risk Patients After ST-Segment–Elevation Myocardial Infarction

Background—

The incidence of angiographic no reflow (NR) and microvascular obstruction (MVO) at cardiac magnetic resonance is significantly different. The aim of this study was to investigate the occurrence of NR and MVO in a cohort of consecutive patients with ST-segment–elevation myocardial infarction treated with primary percutaneous coronary interventions.

Methods and Results—

In this prospective study, 88 consecutive ST-segment–elevation myocardial infarction patients were enrolled within 12 hours from symptoms onset. All patients underwent cardiac magnetic resonance between 2 and 5 days after primary percutaneous coronary interventions. NR was defined as thrombolysis in myocardial infarction flow grade ≤2 and as myocardial blush grade <2. Presence of early or late MVO was assessed 4 and 10 to 15 minutes after gadolinium injection. Thirty-one patients (36%) had evidence of NR, whereas 58 (67%) had MVO. One NR patient did not have MVO. In contrast, NR was present in 30 of 58 MVO patients. MVO patients had higher troponin T peak ( P <0.0001), larger late gadolinium enhancement area ( P <0.0001), and lower left ventricular ejection fraction ( P <0.001) because of an increased end-systolic volume ( P =0.015). In contrast, patients with NR had higher troponin T peak ( P =0.006) but similar late gadolinium enhancement area ( P =0.24) compared with those without NR. Major cardiovascular adverse events–free survival was worse in patients with MVO ( P =0.014), although it was similar in patients with and without NR ( P =0.33). The independent predictors of major cardiovascular adverse events were MVO (hazard ratio, 3.418; P =0.046) and ischemic time (hazard ratio, 1.016; P <0.001). MVO was a strong predictor of target lesion revascularization occurrence ( P =0.017 for log-rank test).

Conclusions—

Compared with coronary angiography performed soon after recanalization of the culprit artery, cardiac magnetic resonance performed during index hospitalization provides better prognostic stratification of ST-segment–elevation myocardial infarction patients treated with primary percutaneous coronary interventions. Another novel finding of our study is a significantly increased rate of clinically driven target lesion revascularization in the index event culprit vessel in patients with MVO.

Role of the C-C chemokine receptor-2 in a murine model of injury-induced osteoarthritis

OBJECTIVE

We previously found in our embryonic studies that proper regulation of the chemokine CCL12 through its sole receptor CCR2, is critical for joint and growth plate development. In the present study, we examined the role of CCR2 in injury-induced-osteoarthritis (OA).

METHOD

We used a murine model of injury-induced-OA (destabilization of medial meniscus, DMM), and systemically blocked CCR2 using a specific antagonist (RS504393) at different times during disease progression. We examined joint degeneration by assessing cartilage (cartilage loss, chondrocyte hypertrophy, MMP-13 expression) and bone lesions (bone sclerosis, osteophytes formation) with or without the CCR2 antagonist. We also performed pain behavioral studies by assessing the weight distribution between the normal and arthritic hind paws using the IITS incapacitance meter.

RESULTS

Testing early vs delayed administration of the CCR2 antagonist demonstrated differential effects on joint damage. We found that OA changes in articular cartilage and bone were ameliorated by pharmacological CCR2 blockade, if given early in OA development: specifically, pharmacological targeting of CCR2 during the first 4 weeks (wks) following injury, reduced OA cartilage and bone damage, with less effectiveness with later treatments. Importantly, our pain-related behavioral studies showed that blockade of CCR2 signaling during early, 1-4 wks post-surgery or moderate, 4-8 wks post-surgery, OA was sufficient to decrease pain measures, with sustained improvement at later stages, after treatment was stopped.

CONCLUSIONS

Our data highlight the potential efficacy of antagonizing CCR2 at early stages to slow the progression of post-injury OA and, in addition, improve pain symptoms.

TWO NEW SINGLE-EXPOSURE, MULTI-DETECTOR NEUTRON SPECTROMETERS FOR RADIATION PROTECTION APPLICATIONS IN WORKPLACE MONITORING

This communication describes two new instruments, based on multiple active thermal neutron detectors arranged within a single moderator, that permit to unfold the neutron spectrum (from thermal to hundreds of MeV) and to determine the corresponding integral quantities with only one exposure. This makes them especially advantageous for neutron field characterisation and workplace monitoring in neutron-producing facilities. One of the devices has spherical geometry and nearly isotropic response, the other one has cylindrical symmetry and it is only sensitive to neutrons incident along the cylinder axis. In both cases, active detectors have been specifically developed looking for the criteria of miniaturisation, high sensitivity, linear response and good photon rejection. The calculated response matrix has been validated by experimental irradiations in neutron reference fields with a global uncertainty of 3%. The measurements performed in realistic neutron fields permitted to determine the neutron spectra and the integral quantities, in particular H*(10).

In vitro evaluation of prosthodontic impression on natural dentition: a comparison between traditional and digital techniques

OBJECTIVES

The aim of this in vitro study is to evaluate the marginal and internal fit of zirconia core crowns manufactured following different digital and traditional workflows.

METHODS

A 6° taper shoulder prepared abutment tooth was used to produce 20 zirconia core crowns using four different scanning techniques: scanned directly with the extraoral lab scanner, scanned with intraoral scanner, dental impressions using individual dental tray and polyether, dental casts from a polyether impressions. Marginal and internal fits were evaluated with digital photography and the silicone replica method.

RESULTS

Medium marginal gaps were 76,00 μm ± 28.9 for extraoral lab scanner, 80.50 μm ± 36,2 for intraoral scanner, 88.10 μm ± 34,8 for dental impression scan and 112,4 μm ± 37,2 for dental cast scan. Medium internal gaps were 23.20 μm ± 10,3 for extraoral lab scanner, 16.20 μm ± 8.3 for intraoral scanner, 27.20 μm ± 16.7 for dental impression scan and 30.20 μm ± 12.7 for dental cast scan.

CONCLUSION

Internal gap were extensively lower than 70 μm described in literature. Marginal fit was higher than ideal values for all the techniques but within the limit of clinical success. Intraoral scanners obtained the best results for internal gap.

Pre-treatment MDCT-based texture analysis for therapy response prediction in gastric cancer: Comparison with tumour regression grade at final histology

PURPOSE

An accurate prediction of tumour response to therapy is fundamental in oncology, so as to prompt personalised treatment options if needed. The aim of this study was to investigate the ability of preoperative texture analysis from multi-detector computed tomography (MDCT) in the prediction of the response rate to neo-adjuvant therapy in patients with gastric cancer.

MATERIAL AND METHODS

Thirty-four patients with biopsy-proven gastric cancer were examined by MDCT before neo-adjuvant therapy, and treated with radical surgery after treatment completion. Tumour regression grade (TRG) at final histology was also assessed. Image features from texture analysis were quantified, with and without filters for fine to coarse textures. Patients with TRG 1-3 were considered responders while TRG 4-5 as non- responders. The response rate to neo-adjuvant therapy was assessed both at univariate and multivariate analysis.

RESULTS

Fourteen parameters were significantly different between the two subgroups at univariate analysis; in particular, entropy and compactness (higher in responders) and uniformity (lower in responders). According to our model, the following parameters could identify non-responders at multivariate analysis: entropy (≤6.86 with a logarithm of Odds Ratio - Log OR -: 4.11; p=0.003); range (>158.72; Log OR: 3.67; p=0.010) and root mean square (≤3.71; Log OR: 4.57; p=0.005). Entropy and three-dimensional volume were not significantly correlated (r=0.06; p=0.735).

CONCLUSION

Pre-treatment texture analysis can potentially provide important information regarding the response rate to neo-adjuvant therapy for gastric cancer, improving risk stratification.

Apparent diffusion coefficient by diffusion-weighted magnetic resonance imaging as a sole biomarker for staging and prognosis of gastric cancer

Objective

To investigate the role of apparent diffusion coefficient (ADC) from diffusion-weighted magnetic resonance imaging (DW-MRI) when applied to the 7th TNM classification in the staging and prognosis of gastric cancer (GC).

Methods

Between October 2009 and May 2014, a total of 89 patients with non-metastatic, biopsy proven GC underwent 1.5T DW-MRI, and then treated with radical surgery. Tumor ADC was measured retrospectively and compared with final histology following the 7th TNM staging (local invasion, nodal involvement and according to the different groups — stage I, II and III). Kaplan-Meier curves were also generated. The follow-up period is updated to May 2016.

Results

Median follow-up period was 33 months and 45/89 (51%) deaths from GC were observed. ADC was significantly different both for local invasion and nodal involvement (P<0.001). Considering final histology as the reference standard, a preoperative ADC cut-off of 1.80×10^–3 mm²/s could distinguish between stages I and II and an ADC value of ≤1.36×10^–3 mm²/s was associated with stage III (P<0.001). Kaplan-Meier curves demonstrated that the survival rates for the three prognostic groups were significantly different according to final histology and ADC cut-offs (P<0.001).

Conclusions

ADC is different according to local invasion, nodal involvement and the 7th TNM stage groups for GC, representing a potential, additional prognostic biomarker. The addition of DW-MRI could aid in the staging and risk stratification of GC.

Abstract A07: Identification of endocrine/metabolic biomarkers associated to early PDC in a transgenic mouse model

Background: Pancreatic ductal adenocarcinoma (PDC) is a deadly disease, even surgery contributes little to survival if PDC is not diagnosed at an initial stage. Glucose homeostasis alteration associated to PDC was described to identify an high risk population for screening. Moreover the weight loss often manifests several months before cachexia. The crosstalk between metabolism and cancer could be a key to early diagnosis. Our aim is to find endocrine/metabolic biomarkers of early PDC development in a gold standard murine model.

Materials and Methods: Candidate markers were investigated using LSL-KrasG12D/+;LSL-Trp53R172H/+;Pdx-1-Cre (KPC) mouse, a genetically-engineered model that develops PDC with 100% penetrance. KPC has been fed with standard diet (SD) or high fat diet (HFD) introducing a further risk factor for diabetes and metabolic alterations. To overcome the problem of asynchronous development of PDC in KPC, 7T-MRI was used to classify mice in actual pathological stage: normal (S1); cystic degeneration (S2); small tumor (S3) and advanced pancreatic cancer (S4). We performed metabolic test (OGTT) and serum endocrine/metabolic profile (xMAP technology and clinical biochemistry) in n=27 KPC (and control mice PDX-1 Cre) fed with HFD vs n=26 KPC (and control mice PDX-1 Cre) fed with SD. To prioritize markers we computed the ROC curve analysis.

Results: i) Glucose metabolism: KPC were normoglycemic regardless of the diet; the AUC in OGTT increases in KPC fed with HFD (HFD vs SD: S1 p&lt;0,001, S2 p&lt;0,001, S3 p=0,002, Cre p&lt;0,001) ii) Serum levels of 29 endocrine/metabolic biomarkers were assessed during disease progression. The more relevant results are: increase of PYY (p&lt;0,003) and decrease of leptin (p&lt;0,02), GIP (p&lt;0.005) albumin (p&lt;0.001) both in HFD and SD fed KPC (Cre vs S2); increase of amylase in stage 1 HFD-fed KPC (p=0,037). Moreover PYY was able to discriminate control from stage 2 KPC with an AUC=0,929 in the ROC curve analysis (p&lt;0,001).

Conclusions: Unlike human, in the mouse model the development of PDC is not associated with an hyperglycemic status, regardless of the diet. However KPC fed with HFD experience a mild impairment of glucose metabolism (as well as in control mice) and a mild pancreatic damage. Our results identify Leptin, PYY, GIP and albumin as markers of early stage PDC in a preclinical model with a diagnostic potential to be validated in human patients.

Citation Format: Valentina Pasquale, Erica Dugnani, Daniela Liberati, Paolo Marra, Tamara Canu, Antonio Esposito, Lorenzo Piemonti1.{Authors}. Identification of endocrine/metabolic biomarkers associated to early PDC in a transgenic mouse model. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2016 May 12-15; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2016;76(24 Suppl):Abstract nr A07.

IFNα gene/cell therapy curbs colorectal cancer colonization of the liver by acting on the hepatic microenvironment

Colorectal cancer (CRC) metastatic dissemination to the liver is one of the most life‐threatening malignancies in humans and represents the leading cause of CRC‐related mortality. Herein, we adopted a gene transfer strategy into mouse hematopoietic stem/progenitor cells to generate immune‐competent mice in which TEMs—a subset of Tie2⁺ monocytes/macrophages found at peritumoral sites—express interferon‐alpha (IFNα), a pleiotropic cytokine with anti‐tumor effects. Utilizing this strategy in mouse models of CRC liver metastasis, we show that TEMs accumulate in the proximity of hepatic metastatic areas and that TEM‐mediated delivery of IFNα inhibits tumor growth when administered prior to metastasis challenge as well as on established hepatic lesions, improving overall survival. Further analyses unveiled that local delivery of IFNα does not inhibit homing but limits the early phases of hepatic CRC cell expansion by acting on the radio‐resistant hepatic microenvironment. TEM‐mediated IFNα expression was not associated with systemic side effects, hematopoietic toxicity, or inability to respond to a virus challenge. Along with the notion that TEMs were detected in the proximity of CRC metastases in human livers, these results raise the possibility to employ similar gene/cell therapies as tumor site‐specific drug‐delivery strategies in patients with CRC.

Breast conservation following neoadjuvant therapy for breast cancer in the modern era: Are we losing the opportunity?

The main rationale for neoadjuvant therapy for breast cancer is to provide effective systemic treatment while surgically down-staging the cancer. This down-staging was initially to convert inoperable patients to operable and later to increase rates of breast conservation in patients initially deemed mastectomy only candidates. Unexpectedly, in recent neoadjuvant trials lower rates of breast conservation have been observed than in past decades, despite remarkable advances in systemic therapies, which have increased pathologic complete response rates. These results point to factors aside from response and eligibility for breast conservation that may lead surgeons and/or patients to recommend and choose mastectomy. Here, we aim to examine the surgical benefits offered by the modern era neoadjuvant therapy and explore factors that have contributed to this decrease in breast conservation rates. If the main benefit of neoadjuvant therapy is to increase the opportunity for breast conservation, then our review suggests that to optimize less invasive surgical approaches, we will need to address both surgeon and patient-level variables and biases that may be limiting our ability to identify patients appropriate for less aggressive options. As an oncology community, we must be aware of the surgical overtreatment of breast cancer, especially in a time where systemic therapies have remarkably improved outcomes and responses.

Prospective comparison of MR with diffusion-weighted imaging, endoscopic ultrasound, MDCT and positron emission tomography-CT in the pre-operative staging of oesophageal cancer: results from a pilot study

OBJECTIVE

To compare the diagnostic performance of MR and diffusion-weighted imaging (DWI), multidetector CT, endoscopic ultrasonography (EUS) and ¹⁸F-FDG (fluorine-18 fludeoxyglucose) positron emission tomography CT (PET-CT) in the pre-operative locoregional staging of oesophageal cancer.

METHODS

18 patients with oesophageal or Siewert I tumour (9 directly treated with surgery and 9 addressed to chemo-/radiotherapy before) underwent 1.5-T MR and DWI, 64-channel multidetector CT, EUS and PET-CT before (n = 18) and also after neoadjuvant treatment (n = 9). All images were analysed and staged blindly by dedicated operators (seventh TNM edition). Two radiologists calculated independently the apparent diffusion coefficient from the first scan. Results were compared with histopathological findings. After the population had been divided according to local invasion (T1-T2 vs T3-T4) and nodal involvement (N0 vs N+), sensitivity, specificity, accuracy, positive- and negative-predictive values were calculated and compared. Quantitative measurements from DWI and PET-CT were also analysed.

RESULTS

For T staging, EUS showed the best sensitivity (100%), whereas MR showed the highest specificity (92%) and accuracy (83%). For N staging, MR and EUS showed the highest sensitivity (100%), but none of the techniques showed adequate results for specificity. Overall, MR showed the highest accuracy (66%) for N stage, although this was not significantly different to the other modalities. The apparent diffusion coefficient was different between surgery-only and chemo-/radiotherapy groups (1.90 vs 1.30 × 10^-3 mm² s^-1, respectively; p = 0.005)-optimal cut off for local invasion: 1.33 × 10^-3 mm² s^-1 (p = 0.05). Difference in standardized uptake value was also very close to conventional levels of statistical significance (8.81 vs 13.97 g cm^-3, respectively; p = 0.05)-optimal cut off: 7.97 g cm^-3 (p = 0.44).

CONCLUSION

In this pilot study, we have shown that MR with DWI could enrich the current pre-operative work-up for oesophageal cancer and could be used for T and N staging. However, larger studies will need to be carried out before introducing this technique in the standard diagnostic pathway, in order to understand if MR with DWI could change its management and replace more costly or invasive tests such as PET-CT or EUS. Advances in knowledge: This pilot study represents the first effort where the four techniques have been prospectively compared together for oesophageal cancer staging. The combination of MR and DWI could provide important, additional information for staging and initial treatment decision-making.