Computed Tomography and Dual-Energy X-Ray Asorptiometry body composition parameter harmonisation to universalise adipose tissue measurements in a population-based cross-sectional study

To harmonise computed tomography (CT) and dual-energy x-ray absorptiometry (DXA) body composition measurements allowing easy conversion in longitudinal assessments and across cohorts to assess cardiometabolic risk and disease. Retrospective cross-sectional observational study from 1996 to 2008 included participants in the Pennington Center Longitudinal Study (PCLS) (N = 1967; 571 African American/1396 White). Anthropometrics, whole-body DXA and abdominal CT images were obtained. Multi-layer segmentation techniques (Analyze; Rochester, MN) quantified visceral adipose tissue (VAT). Clinical biomarkers were obtained from routine blood samples. Linear models were used to predict CT-VAT from DXA-VAT and examine the effects of traditional biomarkers on cross-sectional-VAT. Predicted CT-VAT was highly associated with measured CT-VAT using ordinary least square linear regression analysis and random forest models (R2 = 0.84; 0.94, respectively, p < .0001). Model stratification effects showed low variability between races and sexes. Overall, associations between measured CT-VAT and DXA-predicted CT-VAT were good (R2 > 0.7) or excellent (R2 > 0.8) and improved for all stratification groups except African American men using random forest models. The clinical effects on measured CT-VAT and DXA-VAT showed no significant clinical difference in the measured adipose tissue areas (mean difference = 0.22 cm2). Random forest modelling seamlessly predicts CT-VAT from measured DXA-VAT to a degree of accuracy that falls within the bounds of universally accepted standard error.

A New and Effective Procedure for Advanced Oral Cancer Therapy: The Potential of a Cancer Stem Cell Assay in Guiding Chemotherapy

Introduction

Ineffective anticancer therapy can result in unnecessary toxicity and the development of resistant clones. Many types of solid tumors, including head and neck squamous cell carcinoma, have been found to contain a small population of cancer stem cells (CSCs) that contribute to tumor propagation, maintenance, and treatment resistance.

Materials and methods

Selectively enriched CSCs from primary cancer cell cultures can be used in a chemosensitivity assay for a functional test (ChemoID) that uses patients' live tumor cells to indicate which chemotherapy agent (or "combinations") will kill not only the bulk of tumor cells but also the CSCs that are known to cause cancer to recur. This study aimed to show the potential of testing the sensitivity of CSCs enriched from oral cancer patients' biopsies to conventional chemotherapies. A case series of eleven patients affected by advanced oral squamous cell carcinoma (OSCC) have been included in this study. We compared the results of the CSC assay among all the patients and found that there was variability in the chemotherapy response predicted by the assay.

Results

Variability in chemotherapy response was found by the CSC assay in advanced OSCC patients suggesting more precise and personalized therapies to the Oncologist.

Conclusions

Variability in chemosensitivity for OSCC warrants the need to investigate further the use of the assay in larger cohorts to gain a broader understanding of the utility of the clinical test.

Adiposity and Coagulation: Predicting Postinjury Coagulation With Advanced Imaging Analysis

INTRODUCTION

Anatomic distribution of adipose tissue has demonstrated variable associations with hypercoagulability. Utilizing a retrospective analysis of a previously enrolled prospective cohort, we assessed computed tomography (CT) scan-based anthropometric and volumetric measures of adiposity as predictors of postinjury hypercoagulability.

METHODS

Segmentation analysis of arrival CT scans in significantly injured patients at a single level-I trauma center enrolled from December 2017 to August 2021 were analyzed for anthropometric indices of waist circumference (WC) and sagittal abdominal diameter (SAD), and volumetric parameters of visceral adipose tissue, superficial/deep subcutaneous adipose tissue, psoas/paravertebral muscle volume, and abdominal wall muscle volume. Associations with thromboelastography (TEG) were explored.

RESULTS

Data from 91 patients showed strong correlations between body mass index and standard anthropometric measures of WC and SAD (P < 0.001); calculated volumes of subcutaneous adipose tissue and visceral adipose tissue (P < 0.001); and ratios of subcutaneous adipose:psoas muscle (SP ratio) and visceral adipose:psoas muscle ratio (both with P < 0.001, respectively). Correlation between TEG maximal amplitude (MA) and body mass index and SAD were not significant, with only weak correlation between TEG-MA and WC (r = 0.238, P = 0.041). Moderate but significant correlations existed between SP ratio and TEG-MA (r = 0.340, P = 0.005), but not visceral adipose:psoas muscle ratio (r = 0.159, P = 0.198). The relationship between TEG-MA and SP ratio remained significant when adjusted for injury severity score and lactate level (b = 0.302, P = 0.001).

CONCLUSIONS

SP ratio is more strongly correlated with TEG-MA than standard obesity measures, and independently predicts increasing clot strength/stability after injury. Coagulation-relevant measures of sarcopenic obesity can be measured on CT scan, and may be used to optimize thromboprophylaxis strategies for obese injured patients.

Defining Demographic-specific Coronary Artery Calcium Percentiles in the Population Aged ≥75: The ARIC Study and MESA

BACKGROUND

Current clinical guidelines recommend a coronary artery calcium (CAC) score of 100 Agatston Units or demographic-specific 75th percentile as high-risk thresholds for guiding atherosclerotic cardiovascular disease preventive therapy. Meanwhile, low CAC can help derisk individuals who may safely defer statin therapy. However, limited data from the early 2000s, including just 208 older Black individuals, inform CAC percentiles for adults aged 75 to 85 years, and none have been established in adults aged ≥85 years. This study aims to characterize the distribution of CAC and establish demographic-specific CAC percentiles in the population aged ≥75 years.

METHODS

We assessed 2886 participants aged ≥75 years without clinical coronary heart disease from the ARIC study (Atherosclerosis Risk in Communities) visit 7 (2018-2019; n=2217) and the MESA (Multi-Ethnic Study of Atherosclerosis) visit 5 (2010-2011; n=669). Prevalence of any CAC >0 and sex- and race-specific CAC percentiles across age were estimated nonparametrically with locally weighted regression models and pooled residual ranking.

RESULTS

The median age was 80 (interquartile interval, 77-83) years, and 60% were female. The prevalence of zero CAC was lowest in White males (4%), followed by Black males (13%), White females (14%), and highest in Black females (18%). Regardless of sex and race, most participants had CAC>100 (62.5%). CAC scores increased with age, with CAC identified in ≈95% of participants aged ≥90 years across sex-race subgroups. The 75th percentile corresponded to higher CAC scores for Black older adults (n=741), especially females, than currently used thresholds.

CONCLUSIONS

In community-dwelling adults aged ≥75 years free of clinical coronary heart disease, the prevalence of zero CAC was 11%, and CAC >100 as a threshold for high ASCVD risk would categorize most of this older population as high risk. Demographic-specific CAC percentiles from this study are a valuable tool for interpreting CAC in the population aged ≥75 years.

Cancer stem cell assay-guided chemotherapy improves survival of patients with recurrent glioblastoma in a randomized trial

Therapy-resistant cancer stem cells (CSCs) contribute to the poor clinical outcomes of patients with recurrent glioblastoma (rGBM) who fail standard of care (SOC) therapy. ChemoID is a clinically validated assay for identifying CSC-targeted cytotoxic therapies in solid tumors. In a randomized clinical trial (NCT03632135), the ChemoID assay, a personalized approach for selecting the most effective treatment from FDA-approved chemotherapies, improves the survival of patients with rGBM (2016 WHO classification) over physician-chosen chemotherapy. In the ChemoID assay-guided group, median survival is 12.5 months (95% confidence interval [CI], 10.2-14.7) compared with 9 months (95% CI, 4.2-13.8) in the physician-choice group (p = 0.010) as per interim efficacy analysis. The ChemoID assay-guided group has a significantly lower risk of death (hazard ratio [HR] = 0.44; 95% CI, 0.24-0.81; p = 0.008). Results of this study offer a promising way to provide more affordable treatment for patients with rGBM in lower socioeconomic groups in the US and around the world.

Enhancing Targeted Therapy in Breast Cancer by Ultrasound-Responsive Nanocarriers

Currently, the response to cancer treatments is highly variable, and severe side effects and toxicity are experienced by patients receiving high doses of chemotherapy, such as those diagnosed with triple-negative breast cancer. The main goal of researchers and clinicians is to develop new effective treatments that will be able to specifically target and kill tumor cells by employing the minimum doses of drugs exerting a therapeutic effect. Despite the development of new formulations that overall can increase the drugs’ pharmacokinetics, and that are specifically designed to bind overexpressed molecules on cancer cells and achieve active targeting of the tumor, the desired clinical outcome has not been reached yet. In this review, we will discuss the current classification and standard of care for breast cancer, the application of nanomedicine, and ultrasound-responsive biocompatible carriers (micro/nanobubbles, liposomes, micelles, polymeric nanoparticles, and nanodroplets/nanoemulsions) employed in preclinical studies to target and enhance the delivery of drugs and genes to breast cancer.

Treatment of unmethylated MGMT-promoter recurrent glioblastoma with cancer stem cell assay-guided chemotherapy and the impact on patients' healthcare costs

Background

Glioblastoma (GBM) is a lethal disease. At least in part, the recurrence of GBM is caused by cancer stem cells (CSCs), which are resistant to chemotherapy. Personalized anticancer therapy against CSCs can improve treatment outcomes. We present a prospective cohort study of 40 real-world unmethylated Methyl-guanine-methyl-transferase-promoter GBM patients treated utilizing a CSC chemotherapeutics assay-guided report (ChemoID).

Methods

Eligible patients who underwent surgical resection for recurrent GBM were included in the study. Most effective chemotherapy treatments were chosen based on the ChemoID assay report from a panel of FDA-approved chemotherapies. A retrospective chart review was conducted to determine OS, progression-free survival, and the cost of healthcare costs. The median age of our patient cohort was 53 years (24-76).

Results

Patients treated prospectively with high-response ChemoID-directed therapy, had a median overall survival (OS) of 22.4 months (12.0-38.4) with a log-rank P = .011, compared to patients who could be treated with low-response drugs who had instead an OS of 12.5 months (3.0-27.4 months). Patients with recurrent poor-prognosis GBM treated with high-response therapy had a 63% probability to survive at 12 months, compared to 27% of patients who were treated with low-response CSC drugs. We also found that patients treated with high-response drugs on average had an incremental cost-effectiveness ratio (ICER) of $48,893 per life-year saved compared to $53,109 of patients who were treated with low-response CSC drugs.

Conclusions

The results presented here suggest that the ChemoID Assay can be used to individualize chemotherapy choices to improve poor-prognosis recurrent GBM patient survival and to decrease the healthcare cost that impacts these patients.

Virus-Based Immuno-Oncology Models

Immunotherapy has been extensively explored in recent years with encouraging results in selected types of cancer. Such success aroused interest in the expansion of such indications, requiring a deep understanding of the complex role of the immune system in carcinogenesis. The definition of hot vs. cold tumors and the role of the tumor microenvironment enlightened the once obscure understanding of low response rates of solid tumors to immune check point inhibitors. Although the major scope found in the literature focuses on the T cell modulation, the innate immune system is also a promising oncolytic tool. The unveiling of the tumor immunosuppressive pathways, lead to the development of combined targeted therapies in an attempt to increase immune infiltration capability. Oncolytic viruses have been explored in different scenarios, in combination with various chemotherapeutic drugs and, more recently, with immune check point inhibitors. Moreover, oncolytic viruses may be engineered to express tumor specific pro-inflammatory cytokines, antibodies, and antigens to enhance immunologic response or block immunosuppressive mechanisms. Development of preclinical models capable to replicate the human immunologic response is one of the major challenges faced by these studies. A thorough understanding of immunotherapy and oncolytic viruses’ mechanics is paramount to develop reliable preclinical models with higher chances of successful clinical therapy application. Thus, in this article, we review current concepts in cancer immunotherapy including the inherent and synthetic mechanisms of immunologic enhancement utilizing oncolytic viruses, immune targeting, and available preclinical animal models, their advantages, and limitations.

Abstract CT224: Multi-institutional randomized phase-3 trial comparing cancer stem cell-targeted vs physician-choice treatments in patients with recurrent high-grade gliomas (NCT03632135)

Background: Clinical outcomes in patients with recurrent high-grade glioma (HGG) remain poor. Cancer stem cells (CSCs) have been implicated in metastasis, treatment resistance and recurrence of HHGs. We have shown in several clinical studies that anti-CSC-directed therapy provides benefits in many cancer types; however, this is the first report of a randomized clinical trial evaluating it for recurrent HGGs. Objective: Determine whether CSC-targeted cytotoxic agents selected by ChemoID assay-guided therapy improves survival in patients with recurrent HGG.

Design, Settings, and Participants: In this parallel-group, randomized, phase-3 clinical trial, patients at 13 clinical sites in the USA with grade-III/IV recurrent glioma (2016 WHO guidelines) were randomized 1:1 to either ChemoID assay-guided therapy or physician-choice therapy, and then treated and followed until unacceptable toxic effects, hospice, or death.

Main Outcomes and Measures: The primary endpoint was overall survival (OS).

Results: Combined median follow-up was 9 months. Median OS (mOS) was 12.5 months (95% CI, 10.2-14.7) in the ChemoID assay-guided group vs 9 months (95% CI, 4.2-13.8) in the physician-choice group (log-rank P = .010). Risk of death was significantly lower in the ChemoID assay group (HR = 0.44; 95% CI, 0.24-0.81; P = .008). Median progression free survival (PFS) was 10.1 vs 3.5 months (95% CI, 4.8-15.4 vs 1.9-5.1) (HR, 0.25; 95% CI, 0.14-0.44; P &lt; .001).

Conclusions and Relevance: Primary endpoint was met in this randomized clinical trial. The mOS was 3.5 months longer in the ChemoID assay-guided group vs the physician-choice group demonstrating the clinical advantage of treating HGG patients using CSC personalized therapy.

Citation Format: Tulika Ranjan, Soma Sengupta, Alexander Yu, Candace M. Howard, Ricky Chen, Rekha Chaudhary, Nicholas Marko, Dawit Aregawi, Michael Glantz, Jon Glass, Richard M. Green, Christine Lu-Emerson, Aaron Mammoser, Hugh Moulding, Steven Jubelirer, Jason Schroeder, Mark Anderson, Frances Chow, Seth Lirette, Krista Denning, Anthony Alberico, Jagan Valluri, Pier Paolo Claudio. Multi-institutional randomized phase-3 trial comparing cancer stem cell-targeted vs physician-choice treatments in patients with recurrent high-grade gliomas (NCT03632135) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr CT224.

Cancer stem cell assay for identification of effective treatments for platinum-resistant recurrent ovarian cancer

e17584

Background: Disease recurrence and progression of ovarian cancer is a common event, which is accompanied by the development of platinum-resistant or refractory disease. The presence of chemo-resistant cancer stem cells (CSCs) contributes to tumor propagation, maintenance, and treatment resistance of this difficult to treat disease. The choice of appropriate chemotherapy is critical to the management of advanced epithelial ovarian cancer. We developed a CSCs assay (ChemoID) that identifies the most effective chemotherapy for individual patients from a panel of FDA-approved chemotherapies. Methods: Ascites or interventional radiology biopsies were collected under physician order from 85 consecutive patients affected by 3rd relapsed ovarian cancer. Test results from the assay were used to treat patients with the highest cell kill drugs, taking into consideration their health status and using dose reductions, if needed. Our study assessed the correlation of the ChemoID test results to treatment outcomes independently of other biomarkers. A retrospective chart analysis and review of CT and PET scans were performed to determine patients’ outcomes for tumor response, progression-free survival (PFS), and overall survival (OS). Results: We observed that recurrent ovarian cancer patients treated with high-cell kill chemotherapy agents guided by the ChemoID drug response assay had an improvement in their median PFS and OS when compared to historical median PFS and OS and/or when compared to patients who could not receive high cell kill chemotherapies (PFS low cell kill 3.5 months vs. high cell kill 12.0 months; OS low cell kill 6.0 months vs. high cell kill 15.0 months). Conclusions: The current evidence strongly suggests that the ChemoID assay predicted the effectiveness of specific therapies, as well as improved outcomes for patients treated with assay-sensitive therapies.

Multi-institutional randomized phase 3 trial comparing cancer stem cell-targeted versus physician-choice treatments in patients with recurrent high-grade gliomas (NCT03632135)

2028

Background: Clinical outcomes in patients with recurrent high-grade glioma (HGG) remain poor. Cancer stem cells (CSCs) have been implicated in metastasis, treatment resistance and recurrence of HHGs. We have shown in several clinical studies that anti-CSC-directed therapy selected by ChemoID assay provides benefits in many cancer types; however, this is the first report of a randomized clinical trial evaluating whether CSC-targeted cytotoxic agents selected by ChemoID assay-guided therapy improves survival in patients with recurrent HGG. Methods: In this parallel-group, randomized, phase-3 clinical trial, patients at 13 clinical sites in the USA with grade-III/IV recurrent glioma (2016 WHO guidelines) were randomized 1:1 to either ChemoID assay-guided therapy or physician-choice therapy, and then treated and followed until unacceptable toxic effects, hospice, or death. The primary endpoint was overall survival (OS). Results: Combined median follow-up was 9 months. Median OS (mOS) was 12.5 months (95% CI, 10.2-14.7) in the ChemoID assay-guided group vs 9 months (95% CI, 4.2-13.8) in the physician-choice group (log-rank P =.010). Risk of death was significantly lower in the ChemoID assay group (HR = 0.44; 95% CI, 0.24-0.81; P =.008). Median progression free survival (PFS) was 10.1 vs 3.5 months (95% CI, 4.8-15.4 vs 1.9-5.1) (HR, 0.25; 95% CI, 0.14-0.44; P <.001). Conclusions: Primary endpoint was met in this randomized clinical trial. The mOS was 3.5 months longer in the ChemoID assay-guided group vs the physician-choice group. Clinical trial information: NCT03632135.

Cancer Stem Cell Assay for the Treatment of Platinum-Resistant Recurrent Ovarian Cancer

BACKGROUND

Disease recurrence and progression of ovarian cancer is a common event, which is accompanied by the development of platinum-resistant or refractory disease. The presence of chemo-resistant Cancer Stem Cells (CSCs) contribute to tumor propagation, maintenance, and treatment resistance of this difficult to treat disease. We have developed ChemoID, a cytotoxic synergy assay against CSCs that identifies the most effective chemotherapy treatment from a panel of FDA-approved chemotherapies using fresh cancer biopsies.

PATIENTS AND METHODS

Ascites or interventional radiology biopsies were collected under physician order from 78 consecutive patients affected by 3rd relapsed ovarian cancer. Test results from the assay were used when possible to treat patients with the highest cell kill drugs, taking into consideration their health status and using dose reductions, if needed. A chart analysis and review of CT and PET scans were performed to determine patients' outcomes for tumor response, Progression-Free Survival (PFS), and Overall Survival (OS).

RESULTS

We observed that recurrent ovarian cancer patients treated with high-cell kill chemotherapy agents guided by the CSCs drug response assay had an improvement in their median PFS and OS when compared to historical median PFS and OS and/or when compared to patients who could not receive high cell kill chemotherapies (PFS low cell kill 3.5 months vs. high cell kill 12.0 months; OS low cell kill 6.0 months vs. high cell kill 15.0 months).

CONCLUSION

This data indicates that the drug cytotoxicity assay aimed at targeting CSCs may be a useful tool for optimizing treatment selection when first-line therapy fails, and when there are multiple clinically-acceptable and -equivalent treatments available.

New Minimally Invasive Intraoral Procedure for Condylar Fractures: Clinical Presentation and Considerations on Current Techniques

ABSTRACT

Mandibular fractures are the third most prevalent maxillofacial traumatic events. Surgical approaches to the condyle are a debated topic. This study describes a mini-invasive technique for condylar fracture reduction. The patient of this study suffered multiple traumatic injuries including a carotid artery dissecting aneurysm, which contraindicated the standard open reduction and internal fixation technique. The novel minimally invasive technique involves intraoral access and fracture fragment realignment using a periosteal elevator, a molar occlusal splint, and intermaxillary fixation after intraoperative radiologic imaging confirmation of condyle reposition.The approach avoids skin incisions and tissue dissection, with good aesthetic outcomes and facial nerve preservation. This technique proved to be safe and simple to be less demanding for the patient, with a shorter recovery time than experienced with other techniques.The results suggest this technique is a good option for the surgical treatment of condylar neck fractures showing favorable rim morphology with primary stability after reduction.

Multifocal IgG4-related aortitis and periaortitis simulating aortic dissection

Immunoglobulin G4-related aortitis (IgG4-RA) is histologically characterized by the infiltration of IgG4 positive plasma cells and fibrosis in systemic organs and the elevation of serum IgG4 levels. The cardiovascular system is commonly involved with various possible presentations such as aortitis, arteritis, periaortitis, periarteritis, and inflammatory aneurysm. We present a case of a 48-year-old male without known previous medical history, admitted for further workup of long-standing chest pain and shortness of breath with suspected aortic dissection on initial assessment. Investigation with computed tomography angiography (CTA) and magnetic resonance angiography (MRA) indicated severe thoracic and abdominal aortoarteritis associated with an ascending thoracic aortic aneurysm, which was confirmed to be IgG4-RA on histopathologic analysis. Thoracic and abdominal IgG4-RA clinical and radiological presentation may simulate other causes of acute aortic syndrome such as aortic dissection, atherosclerotic aneurysm and inflammatory conditions. Accurate recognition of IgG4-RA diagnostic imaging features are essential for early diagnosis and treatment surveillance.

Epi-Mucosa Fixation and Autologous Platelet-Rich Fibrin Treatment in Medication-Related Osteonecrosis of the Jaw

Medication-related osteonecrosis of the jaw (MRONJ) frequently affects patients after treatments with bisphosphonates or denosumab, especially with high doses in patients with bone osteoporosis, neoplastic metastases, or possibly anti-angiogenic treatment for cancer. The aim of this article was to show a new treatment planning for stage 2 and stage 3 MRONJ using platelet-rich fibrin (PRF) at the surgical field to enhance healing in association with a new epi-mucosal fixation technique to prevent or treat mandibular fracture. Two cases were treated by epi-mucosa fixation and autologous PRF use for prevention of mandibular fracture risks related to necrotic bone resection or a narrow fracture reduction. Both cases were successfully treated by this new technique of epi-mucosa fixation combined with autologous PRF and achieved good results and good quality of life. Ability to wear prosthesis with good mastication in the absence of side effect such as infection, plate and screw mobilization, pain, and other disabilities or extension of necrosis was reported. After surgical removal of necrotic bone, no infection was detected without any extension of the necrosis.

Left ventricular pseudoaneurysm: An unexpected finding

A left ventricle pseudoaneurysm (LV PSA) is defined as a free wall rupture of the left ventricle contained by the adjacent pericardial tissue. This rare complication is most commonly encountered following myocardial infarction, trauma, or infection. Surgery is typically warranted to avoid progression to spontaneous rupture, which may potentially lead to cardiac tamponade and death. Cardiac magnetic resonance imaging is the modality of choice to characterize left ventricle morphology and function. Accurate distinction between a pseudoaneurysm and a true aneurysm is crucial, since management and prognosis are significantly different between these 2 entities. We present a case of a 63-year-old male heart transplant recipient, admitted for suspicion of acute cellular rejection, with an unexpected finding of a LV PSA.

Clinical relevance of cancer stem cell chemotherapeutic assay for recurrent ovarian cancer

Introduction

Disease recurrence and progression of ovarian cancer is common with the development of platinum-resistant or refractory disease. This is due in large part to the presence of chemo-resistant cancer stem cells (CSCs) that contribute to tumor propagation, maintenance, and treatment resistance. We developed a CSCs drug cytotoxicity assay (ChemoID) to identify the most effective chemotherapy treatment from a panel of FDA approved chemotherapies.

Methods

Ascites and pleural fluid samples were collected under physician order from 45 consecutive patients affected by 3rd-5th relapsed ovarian cancer. Test results from the assay were used to treat patients with the highest cell kill drugs, taking into consideration their health status and using dose reductions, as needed. A retrospective chart review of CT and PET scans was used to determine patients' outcomes for tumor response, time to recurrence, progression-free survival (PFS), and overall survival (OS).

Results

We observed that recurrent ovarian cancer patients treated with high-cell kill chemotherapy agents guided by the CSCs drug response assay had an improvement in the median PFS corresponding to 5.4 months (3rd relapse), 3.6 months (4th relapse), and 3.9 months (5th relapse) when compared to historical data. Additionally, we observed that ovarian cancer patients identified as non-responders by the CSC drug response assay had 30 times the hazard of death compared to those women that were identified as responders with respective median survivals of 6 months vs. 13 months. We also found that ChemoID treated patients on average had an incremental cost-effectiveness ratio (ICER) between -$18,421 and $7,241 per life-year saved (LYS).

Conclusions

This study demonstrated improved PFS and OS for recurrent ovarian cancer patients treated with assay-guided chemotherapies while decreasing the cost of treatment.

•

Ovarian cancer progression and recurrence is mostly attributed to the presence of cancer stem cells (CSCs), which are chemo-resistant.

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Eliminating CSCs is a strategy that could improve patients' outcome.

•

We developed a CSC drug cytotoxicity assay to identify the most effective chemotherapy treatment from a panel of FDA approved chemotherapies.

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Recurrent ovarian cancer patients treated with high-cell kill chemotherapy agents guided by the CSCs drug response assay had an improvement in the median PFS when compared to historical data.

Cancer Stem Cell Chemotherapeutics Assay for Prospective Treatment of Recurrent Glioblastoma and Progressive Anaplastic Glioma: A Single-Institution Case Series

BACKGROUND: Chemotherapy-resistant cancer stem cells (CSC) may lead to tumor recurrence in glioblastoma (GBM). The poor prognosis of this disease emphasizes the critical need for developing a treatment stratification system to improve outcomes through personalized medicine. METHODS: We present a case series of 12 GBM and 2 progressive anaplastic glioma cases from a single Institution prospectively treated utilizing a CSC chemotherapeutics assay (ChemoID) guided report. All patients were eligible to receive a stereotactic biopsy and thus undergo ChemoID testing. We selected one of the most effective treatments based on the ChemoID assay report from a panel of FDA approved chemotherapy as monotherapy or their combinations for our patients. Patients were evaluated by MRI scans and response was assessed according to RANO 1.1 criteria. RESULTS: Of the 14 cases reviewed, the median age of our patient cohort was 49 years (21–63). We observed 6 complete responses (CR) 43%, 6 partial responses (PR) 43%, and 2 progressive diseases (PD) 14%. Patients treated with ChemoID assay-directed therapy, in combination with other modality of treatment (RT, LITT), had a longer median overall survival (OS) of 13.3 months (5.4-NA), compared to the historical median OS of 9.0 months (8.0–10.8 months) previously reported. Notably, patients with recurrent GBM or progressive high-grade glioma treated with assay-guided therapy had a 57% probability to survive at 12 months, compared to the 27% historical probability of survival observed in previous studies. CONCLUSIONS: The results presented here suggest that the ChemoID Assay has the potential to stratify individualized chemotherapy choices to improve recurrent and progressive high-grade glioma patient survival.

Importance of the Study

Glioblastoma (GBM) and progressive anaplastic glioma are the most aggressive brain tumor in adults and their prognosis is very poor even if treated with the standard of care chemoradiation Stupp's protocol. Recent knowledge pointed out that current treatments often fail to successfully target cancer stem cells (CSCs) that are responsible for therapy resistance and recurrence of these malignant tumors. ChemoID is the first and only CLIA (clinical laboratory improvements amendment) -certified and CAP (College of American Pathologists) -accredited chemotherapeutic assay currently available in oncology clinics that examines patient's derived CSCs susceptibility to conventional FDA (Food and Drugs Administration) -approved drugs. In this study we observed that although the majority of our patients (71.5%) presented with unfavorable prognostic predictors (wild type IDH-1/2 and unmethylated MGMT promoter), patients treated with ChemoID assay-directed therapy had an overall response rate of 86% and increased median OS of 13.3 months compared to the historical median OS of 9.1 months (8.1–10.1 months) previously reported [1] suggesting that the ChemoID assay may be beneficial in personalizing treatment strategies.

Microbubble-mediated delivery of human adenoviruses does not elicit innate and adaptive immunity response in an immunocompetent mouse model of prostate cancer

Background

Gene transfer to malignant sites using human adenoviruses (hAds) has been limited because of their immunogenic nature and host specificity. Murine cells often lack some of the receptors needed for hAds attachment, thus murine cells are generally non-permissive for human adenoviral infection and replication, which limits translational studies.

Methods

We have developed a gene transfer method that uses a combination of lipid-encapsulated perfluorocarbon microbubbles and ultrasound to protect and deliver hAds to a target tissue, bypassing the requirement of specific receptors.

Results

In an in vitro model, we showed that murine TRAMP-C2 and human DU145 prostate cancer cells display a comparable expression pattern of receptors involved in hAds adhesion and internalization. We also demonstrated that murine and human cells showed a dose-dependent increase in the percentage of cells transduced by hAd-GFP (green fluorescent protein) after 24 h and that GFP transgene was efficiently expressed at 48 and 72 h post-transduction. To assess if our image-guided delivery system could effectively protect the hAds from the immune system in vivo, we injected healthy immunocompetent mice (C57BL/6) or mice bearing a syngeneic prostate tumor (TRAMP-C2) with hAd-GFP/MB complexes. Notably, we did not observe activation of innate (TNF-α and IL-6 cytokines), or adaptive immune response (neutralizing antibodies, INF-γ+ CD8⁺ T cells).

Conclusions

This study brings us a step closer to demonstrating the feasibility of murine cancer models to investigate the clinical translation of image guided site-specific adenoviral gene therapy mediated by ultrasound-targeted microbubble destruction.

Electronic supplementary material

The online version of this article (10.1186/s12967-019-1771-0) contains supplementary material, which is available to authorized users.

Multiparametric Magnetic Resonance Imaging in the Assessment of Primary Brain Tumors Through Radiomic Features: A Metric for Guided Radiation Treatment Planning

Purpose The definition of radiotherapy target volume is a critical step in treatment planning for all tumor sites. Conventional magnetic resonance imaging (MRI) pulse sequences are used for the definition of the gross target volume (GTV) and the contouring of glioblastoma multiforme (GBM) and meningioma. We propose the use of multiparametric MRI combined with radiomic features to improve the texture-based differentiation of tumor from edema for GTV definition and to differentiate vasogenic from tumor cell infiltration edema. Methods Twenty-five patients with brain tumor and peritumoral edema (PTE) were assessed. Of the enrolled patients, 17 (63 ± 10 years old, six female and 11 male patients) were diagnosed with GBM and eight (64 ± 14 years old, five female and three male patients) with meningioma. A 3 Tesla (3T) MRI scanner was used to scan patients using a 3D multi-echo Gradient Echo (GRE) sequence. After the acquisition process, two experienced neuroradiologists independently used an in-house semiautomatic algorithm to conduct a segmentation of two regions of interest (ROI; edema and tumor) in all patients using functional MRI sequences, apparent diffusion coefficient (ADC), and dynamic contrast-enhanced MRI (DCE-MRI), as well as anatomical MRI sequences-T1-weighted, T2-weighted and fluid-attenuated inversion recovery (FLAIR). Radiomic (computer-extracted texture) features were extracted from all ROIs through different approaches, including first-, second-, and higher-order statistics, both with and without normalization, leading to the calculation of around 300 different texture parameters for each ROI. Based on the extracted parameters, a least absolute shrinkage and selection operator (LASSO) analysis was used to isolate the parameters that best differentiated edema from tumors while irrelevant parameters were discarded. Results and conclusions The parameters chosen by LASSO were used to perform statistical analyses which allowed identification of the variables with the best discriminant ability in all scenarios. Receiver operating characteristic results showcase both the best single discriminator and the discriminant capacity of the model using all variables selected by LASSO. Excellent results were obtained for patients with GBM with all MRI sequences, with and without normalization; a T1-weighted sequence postcontrast (T1W+C) with normalization offered the best tumor classification (area under the curve, AUC > 0.97). For patients with meningioma, a good model of tumor classification was obtained through the T1-weighted sequence (T1W) without normalization (AUC > 0.71). However, there was no agreement between the results of both radiologists for some MRI sequences analyzed for patients with GBM and meningioma. In conclusion, a small subset of radiomic features showed an excellent ability to distinguish edema from tumor tissue through its most discriminating features.

Assessment of Treatment Response Following Yttrium-90 Transarterial Radioembolization of Liver Malignancies

Transarterial radioembolization using yttrium-90 microspheres is an established and effective treatment for liver malignancies. Determining response to this treatment is difficult due to the radical changes that occur in tissue as a response to radiation. Though accurate assessment of treatment response is paramount for proper patient disposition, there is currently no standardized assessment protocol. Current methods of assessment often consider changes in size, necrosis, vascularity, fluorodeoxyglucose-positron emission tomography FDG-PET metabolic activity, and diffusion using diffusion-weighted magnetic resonance imaging (DWI). Current methods of assessment require a lag time of one to two months post-treatment to determine treatment effectiveness. This delay is a hindrance to obtaining better patient outcomes, giving rise to a need to identify markers for faster determination of treatment efficacy.

Emergence of Radiomics: Novel Methodology Identifying Imaging Biomarkers of Disease in Diagnosis, Response, and Progression

Radiomics is an emerging area within clinical radiology research. It seeks to take full advantage of all the information contained in multiple medical imaging modalities. With a radiomics approach, medical images are not limited to providing only a qualitative assessment but can also provide quantitative data by parameterizing image features. These parameters can be used to identify regions and volumes of interest and discriminate normal healthy tissue from abnormal or diseased tissue. Radiomics is an interlinked sequence of processes of vital importance that begins with the acquisition and selection of medical images that involve standardization of acquisition protocols and inter-equipment normalization. This is followed by the identification and segmentation of regions or volumes of interest by expert radiologists through the use of computational tools that offer speed while reducing variability and bias. The segmentation process is the most critical stage in radiomics. This sometimes requires the incorporation of a pre-processing stage consisting of advanced techniques (reconstruction processes, filtering, etc.). Thereafter, representative characteristics of the region or volume of interest are extracted by approaches based on statistics, morphological features, and transform-based variables. Next, a statistical selection of the parameters that provide a high association and correlation with the clinical condition of interest is performed. Finally, processes such as data integration, standardization, classification, and mining processes can be applied as needed for particular applications. Ongoing research in radiomics aims to reduce the time and costs involved in interpreting medical images while simultaneously increasing the quality of diagnoses and monitoring of as well as the selection of treatment strategies. The results of many studies combining radiomics with standard medical techniques are highly encouraging, and these new approaches are increasingly used. This review article details the components of radiomics and discusses its applications, challenges, and future directions for this exciting new field of study.

Ultrasound targeted gene therapy in a mouse model of prostate cancer: Evaluation of immune response

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Background: Gene transfer to malignant sites using human adenoviruses (hAd) has been limited because of their immunogenicity. Murine cells often lack some of the receptors needed for hAd infection; therefore, are generally non-permissive for hAd infection and replication, which limits translational studies of adenoviral gene transfer techniques. We developed a gene transfer method, which uses a combination of lipid-encapsulated perfluorocarbon microbubbles (MBs) and ultrasound (US) to shield and deliver hAds to a specific tissue bypassing the requirement of the coxsackie and adenovirus receptor (CAR). Methods: Transduction efficiency and GFP protein expression of hAd.GFP was assessed by flow cytometry and fluorescence microscopy in murine TRAMP-C2 and human DU145 prostate cancer cells. Innate and acquired immunity response was determined by ELISA and CTL assay in C57BL/6 mice bearing TRAMP-C2 syngeneic tumor grafts following injections of MBs-Ad.GFP complexes in the presence or absence of ultrasound. Results: We observed that the murine prostate cancer cells TRAMP-C2 were transduced less efficiently by hAd.GFP than the human DU145 cells. We showed in vitro that the transduction rate was increased significantly in both TRAMP-C2 and DU145 prostate cancer cells when delivering the Ad particles by a combination of MBs and US. Moreover, we observed expression of the GFP transgene in both cell lines at 48 hours and 72 hours. Lack of activation of the innate and acquired immunity was observed in vivo by quantifying IL-6 and TNF-α cytokines, and by assaying neutralizing IgG antibodies and CTLs activity, following intratumoral or intravenous injections of MBs-Ad.GFP complexes in the presence or absence of ultrasound. Conclusions: This study demonstrates the feasibility of using the TRAMP-C2 murine model of prostate adenocarcinoma to translate our ultrasound-mediated MB-Ad delivery system from the bench to the clinic. Our data provides evidence that the TRAMP-C2 prostate cancer graft model is a suitable system to study in immune competent animals the capacity of lipid-encapsulated perfluorocarbon MBs and US, to shield and deliver hAds to a site-specific tissue bypassing the requirement of specific receptors.

Analysis of chemo-predictive assay for targeting cancer stem cells in 41 glioblastoma patients

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Background: We have developed a drug response assay (ChemoID) that identifies effective chemotherapy against cancer stem cells (CSCs) vs. bulk of tumor cells from of a panel of potential treatments. A prospective study was conducted evaluating the use of the CSC drug response assay in glioblastoma patients treated with standard-of-care. Methods: 41 glioblastoma patients were enrolled in an IRB-approved protocol. Patients were all treated with standard-of-care TMZ plus radiation with or without maximal surgery. Patients were prospectively monitored for tumor response, time to recurrence, progression-free survival (PFS), and overall survival (OS). Results: For every 5% increase in in-vitro CSC cell kill by TMZ, 12-month patient response (non-recurrence of cancer) increased 2-fold, OR=2.2 (p=0.016). Similar associations with the bulk tumor test were seen, OR=2.75 (p=0.07) for each 5% bulk tumor cell kill by TMZ. Combining CSC and bulk tumor assay results in a single model yielded a statistically supported CSC association, OR=2.36 (p=0.036) but a much attenuated remaining bulk tumor association, OR=1.46 (p=0.472). Areas under the curve (AUC) and [sensitivity/specificity] at optimal outpoints (>40% CSC cell kill and >55% bulk tumor cell kill) were AUC=0.989 [Sens=100/Spec=97], 0.972 [100/89] and 0.989 [100/97] for the CSC only, bulk tumor only, and combined models, respectively. Risk categorization of patients was improved by 11% when using the CSC test in conjunction with the bulk test (risk reclassification non-event NRI and overall NRI = 0.111, p=0.030). Median recurrence time was 20 months for patients with a positive (>40% cell kill) CSC test versus only 3 months with a negative CSC test, whereas median recurrence time was 13 months versus 4 months for patients with a positive (>55% cell kill) bulk test versus negative. Similar favorable results for the CSC test were observed for PFS and OS. Results across 14 potential other treatments indicated that 34/41 (83%) and 27/41 (66%) potentially more optimal alternative therapies may have been chosen using CSC results and Bulk results, respectively. Conclusions: The ChemoID assay has the potential to increase the accuracy of bulk tumor assays.

Platelet-Rich Fibrin (PRF) in Implants Dentistry in Combination with New Bone Regenerative Flapless Technique: Evolution of the Technique and Final Results

Most common techniques for alveolar bone augmentation are guided bone regeneration (GBR) and autologous bone grafting. GBR studies demonstrated long-term reabsorption using heterologous bone graft. A general consensus has been achieved in implant surgery for a minimal amount of 2 mm of healthy bone around the implant. A current height loss of about 3-4 mm will result in proper deeper implant insertion when alveolar bone expansion is not planned because of the dome shape of the alveolar crest. To manage this situation a split crest technique has been proposed for alveolar bone expansion and the implants' insertion in one stage surgery. Platelet-rich fibrin (PRF) is a healing biomaterial with a great potential for bone and soft tissue regeneration without inflammatory reactions, and may be used alone or in combination with bone grafts, promoting hemostasis, bone growth, and maturation.

AIM

The aim of this study was to demonstrate the clinical effectiveness of PRF combined with a new split crest flapless modified technique in 5 patients vs. 5 control patients.

MATERIALS AND METHODS

Ten patients with horizontal alveolar crests deficiency were treated in this study, divided into 2 groups: Group 1 (test) of 5 patients treated by the flapless split crest new procedure; Group 2 (control) of 5 patients treated by traditional technique with deeper insertion of smaller implants without split crest. The follow-up was performed with x-ray orthopantomography and intraoral radiographs at T0 (before surgery), T1 (operation time), T2 (3 months) and T3 (6 months) post-operation.

RESULTS

All cases were successful; there were no problems at surgery and post-operative times. All implants succeeded osteointegration and all patients underwent uneventful prosthetic rehabilitation. Mean height bone loss was 1 mm, measured as bone-implant most coronal contact (Δ-BIC), and occurred at immediate T2 post-operative time (3 months). No alveolar bone height loss was detected at implant insertion time, which was instead identified in the control group because of deeper implant insertion.

CONCLUSION

This modified split crest technique combined with PRF appears to be reliable, safe, and to improve the clinical outcome of patients with horizontal alveolar crests deficiency compared to traditional implanting techniques by avoiding alveolar height-loss related to deeper insertion of smaller implants.

Analysis of Chemopredictive Assay for Targeting Cancer Stem Cells in Glioblastoma Patients

INTRODUCTION

The prognosis of glioblastoma (GBM) treated with standard-of-care maximal surgical resection and concurrent adjuvant temozolomide (TMZ)/radiotherapy remains very poor (less than 15 months). GBMs have been found to contain a small population of cancer stem cells (CSCs) that contribute to tumor propagation, maintenance, and treatment resistance. The highly invasive nature of high-grade gliomas and their inherent resistance to therapy lead to very high rates of recurrence. For these reasons, not all patients with similar diagnoses respond to the same chemotherapy, schedule, or dose. Administration of ineffective anticancer therapy is not only costly but more importantly burdens the patient with unnecessary toxicity and selects for the development of resistant cancer cell clones. We have developed a drug response assay (ChemoID) that identifies the most effective chemotherapy against CSCs and bulk of tumor cells from of a panel of potential treatments, offering great promise for individualized cancer management. Providing the treating physician with drug response information on a panel of approved drugs will aid in personalized therapy selections of the most effective chemotherapy for individual patients, thereby improving outcomes. A prospective study was conducted evaluating the use of the ChemoID drug response assay in GBM patients treated with standard of care.

METHODS

Forty-one GBM patients (mean age 54 years, 59% male), all eligible for a surgical biopsy, were enrolled in an Institutional Review Board-approved protocol, and fresh tissue samples were collected for drug sensitivity testing. Patients were all treated with standard-of-care TMZ plus radiation with or without maximal surgery, depending on the status of the disease. Patients were prospectively monitored for tumor response, time to recurrence, progression-free survival (PFS), and overall survival (OS). Odds ratio (OR) associations of 12-month recurrence, PFS, and OS outcomes were estimated for CSC, bulk tumor, and combined assay responses for the standard-of-care TMZ treatment; sensitivities/specificities, areas under the curve (AUCs), and risk reclassification components were examined.

RESULTS

Median follow-up was 8 months (range 3-49 months). For every 5% increase in in vitro CSC cell kill by TMZ, 12-month patient response (nonrecurrence of cancer) increased two-fold, OR=2.2 (P=.016). Similar but somewhat less supported associations with the bulk tumor test were seen, OR=2.75 (P=.07) for each 5% bulk tumor cell kill by TMZ. Combining CSC and bulk tumor assay results in a single model yielded a statistically supported CSC association, OR=2.36 (P=.036), but a much attenuated remaining bulk tumor association, OR=1.46 (P=.472). AUCs and [sensitivity/specificity] at optimal outpoints (>40% CSC cell kill and >55% bulk tumor cell kill) were AUC=0.989 [sensitivity=100/specificity=97], 0.972 [100/89], and 0.989 [100/97] for the CSC only, bulk tumor only, and combined models, respectively. Risk categorization of patients was improved by 11% when using the CSC test in conjunction with the bulk test (risk reclassification nonevent net reclassification improvement [NRI] and overall NRI=0.111, P=.030). Median recurrence time was 20 months for patients with a positive (>40% cell kill) CSC test versus only 3 months for those with a negative CSC test, whereas median recurrence time was 13 months versus 4 months for patients with a positive (>55% cell kill) bulk test versus negative. Similar favorable results for the CSC test were observed for PFS and OS outcomes. Panel results across 14 potential other treatments indicated that 34/41 (83%) potentially more optimal alternative therapies may have been chosen using CSC results, whereas 27/41 (66%) alternative therapies may have been chosen using bulk tumor results.

CONCLUSIONS

The ChemoID CSC drug response assay has the potential to increase the accuracy of bulk tumor assays to help guide individualized chemotherapy choices. GBM cancer recurrence may occur quickly if the CSC test has a low in vitro cell kill rate even if the bulk tumor test cell kill rate is high.

Advances in molecular preclinical therapy mediated by imaging

Several advances have been made toward understanding the biology of cancer and most of them are due to robust genetic studies that led to the scientific recognition that although many patients have the same type of cancer their tumors may have harbored different molecular alterations. Personalized therapy and the development of advanced techniques of preclinical imaging and new murine models of disease are emerging concepts that are allowing mapping of disease markers in vivo and in some cases also receptor targeted therapy. Aim of this review is to illustrate some emerging models of disease that allow patient tumor implantation in mice for subsequent drug testing and advanced approaches for therapy mediated by preclinical imaging. In particular we discuss targeted therapy mediated by high frequency ultrasound and magnetic resonance, two emerging techniques in molecular preclinical therapy.

Metastatic renal cell carcinoma imaging evaluation in the era of anti-angiogenic therapies

During the last decade, the arsenal of anti-angiogenic (AAG) agents used to treat metastatic renal cell carcinoma (RCC) has grown and revolutionized the treatment of metastatic RCC, leading to improved overall survival compared to conventional chemotherapy and traditional immunotherapy agents. AAG agents include inhibitors of vascular endothelial growth factor receptor signaling pathways and mammalian target of rapamycin inhibitors. Both of these classes of targeted agents are considered cytostatic rather than cytotoxic, inducing tumor stabilization rather than marked tumor shrinkage. As a result, decreases in tumor size alone are often minimal and/or occur late in the course of successful AAG therapy, while tumor devascularization is a distinct feature of AAG therapy. In successful AAG therapy, tumor devascularization manifests on computed tomography images as a composite of a decrease in tumor size, a decrease in tumor attenuation, and the development of tumor necrosis. In this article, we review Response Evaluation Criteria in Solid Tumors (RECIST)-the current standard of care for tumor treatment response assessment which is based merely on changes in tumor length-and its assessment of metastatic RCC tumor response in the era of AAG therapies. We then review the features of an ideal tumor imaging biomarker for predicting metastatic RCC response to a particular AAG agent and serving as a longitudinal tumor response assessment tool. Finally, a discussion of the more recently proposed imaging response criteria and new imaging trends in metastatic RCC response assessment will be reviewed.

Ultrasound-mediated oncolytic virus delivery and uptake for increased therapeutic efficacy: state of art

The field of ultrasound (US) has changed significantly from medical imaging and diagnosis to treatment strategies. US contrast agents or microbubbles (MB) are currently being used as potential carriers for chemodrugs, small molecules, nucleic acids, small interfering ribonucleic acid, proteins, adenoviruses, and oncolytic viruses. Oncolytic viruses can selectively replicate within and destroy a cancer cell, thus making them a powerful therapeutic in treating late-stage or metastatic cancer. These viruses have been shown to have robust activity in clinical trials when injected directly into tumor nodules. However limitations in oncolytic virus’ effectiveness and its delivery approach have warranted exploration of ultrasound-mediated delivery. Gene therapy bearing adenoviruses or oncolytic viruses can be coupled with MBs and injected intravenously. Following application of US energy to the target region, the MBs cavitate, and the resulting shock wave enhances drug, gene, or adenovirus uptake. Though the underlying mechanism is yet to be fully understood, there is evidence to suggest that mechanical pore formation of cellular membranes allows for the temporary uptake of drugs. This delivery method circumvents the limitations due to stimulation of the immune system that prevented intravenous administration of viruses. This review provides insight into this intriguing new frontier on the delivery of oncolytic viruses to tumor sites.

The Effects of Melatonin on Brain Arginine Vasotocin: Relationship with Sex and Seasonal Differences in Melatonin Receptor Type 1 in Green Treefrogs (Hyla cinerea)

The neuroendocrine mechanisms by which animals synchronise their physiological state with environmental cues are vital to timing life-history events appropriately. One important endocrine transducer of environmental cues in vertebrates is the pineal hormone melatonin, the secretion of which is directly sensitive to photoperiod and temperature. Melatonin modulates arginine vasotocin (AVT)-immunoreactive (-IR) cell number in the brain of green treefrogs (Hyla cinerea) during the summer breeding season, and this modulation is sexually dimorphic. In the present study, we investigated whether the influence of melatonin on vasotocin varies seasonally. We show that treatment of nonreproductive male green treefrogs with melatonin-filled silastic implants for 4 weeks during the winter does not alter vasotocin-IR cell number in any brain region (i.e. nucleus accumbens, amygdala, preoptic area, suprachiasmatic nucleus or ventral hypothalamus). Taken together, these results suggest that the influence of melatonin on AVT is associated with sex and seasonal variation in melatonin receptor expression. We tested this hypothesis by using immunohistochemistry to characterise the distribution of melatonin receptor type 1 (MT1, also known as Mel1a) in the brain of reproductive and nonreproductive male and female frogs. We quantified MT1-IR cell number in regions known to contain AVT cell populations. Reproductive males had significantly more MT1-IR cells than nonreproductive males in all brain regions, including the combined nucleus accumbens, diagonal band of Broca and septum, striatum, amygdala, combined preoptic area and suprachiasmatic nucleus, as well as the ventral hypothalamus. In the accumbens region, where the effect of melatonin on AVT is known to be sexually dimorphic, males had significantly more MT1-IR cells than females during the summer breeding season. Based on these findings, we suggest that MT1 plays a role in mediating the interactions between melatonin and vasotocin that regulate seasonal and sexually dimorphic changes in sociosexual behaviour.

Microbubble-assisted p53, RB, and p130 gene transfer in combination with radiation therapy in prostate cancer

Combining radiation therapy and direct intratumoral (IT) injection of adenoviral vectors has been explored as a means to enhance the therapeutic potential of gene transfer. A major challenge for gene transfer is systemic delivery of nucleic acids directly into an affected tissue. Ultrasound (US) contrast agents (microbubbles) are viable candidates to enhance targeted delivery of systemically administered genes. Here we show that p53, pRB, and p130 gene transfer mediated by US cavitation of microbubbles at the tumor site resulted in targeted gene transduction and increased reduction in tumor growth compared to DU-145 prostate cancer cell xenografts treated intratumorally with adenovirus (Ad) or radiation alone. Microbubble-assisted/US-mediated Ad.p53 and Ad.RB treated tumors showed significant reduction in tumor volume compared to Ad.p130 treated tumors (p<0.05). Additionally, US mediated microbubble delivery of p53 and RB combined with external beam radiation resulted in the most profound tumor reduction in DU-145 xenografted nude mice (p<0.05) compared to radiation alone. These findings highlight the potential therapeutic applications of this novel image-guided gene transfer technology in combination with external beam radiation for prostate cancer patients with therapy resistant disease.

A novel phantom model for mouse tumor dose assessment under MV beams

In order to determine a mouse's dose accurately and prior to engaging in live mouse radiobiological research, a tissue-equivalent tumor-bearing phantom mouse was constructed and bored to accommodate detectors. Comparisons were made among four different types of radiation detectors, each inserted into the mouse phantom for radiation measurement under a 6 MV linear accelerator beam. Dose detection response from a diode, thermoluminescent dosimeters, and metal-oxide semiconductor field-effect transistors were used and compared to that of a reference pinpoint ionization chamber. A computerized treatment planning system was also directly compared to the chamber. Each detector system demonstrated results similar to the dose computed by the treatment planning system, although some differences were noted. The average disagreement from an accelerator calibrated output dose prescription in the range of 200-400 cGy was -0.4% ± 0.5 σ for the diode, -2.4% ± 2.6 σ for the TLD, -2.9% ± 5.0 σ for the MOSFET, and +1.3% ± 1.4 σ for the treatment planning system. This phantom mouse design is unique, simple, reproducible, and therefore recommended as a standard approach to dosimetry for radiobiological mouse studies by means of any of the detectors used in this study. The authors fully advocate for treatment planning modeling when possible prior to linac-based dose delivery.

Rapid selection and proliferation of CD133+ cells from cancer cell lines: chemotherapeutic implications

Cancer stem cells (CSCs) are considered a subset of the bulk tumor responsible for initiating and maintaining the disease. Several surface cellular markers have been recently used to identify CSCs. Among those is CD133, which is expressed by hematopoietic progenitor cells as well as embryonic stem cells and various cancers. We have recently isolated and cultured CD133 positive [CD133(+)] cells from various cancer cell lines using a NASA developed Hydrodynamic Focusing Bioreactor (HFB) (Celdyne, Houston, TX). For comparison, another bioreactor, the rotary cell culture system (RCCS) manufactured by Synthecon (Houston, TX) was used. Both the HFB and the RCCS bioreactors simulate aspects of hypogravity. In our study, the HFB increased CD133(+) cell growth from various cell lines compared to the RCCS vessel and to normal gravity control. We observed a (+)15-fold proliferation of the CD133(+) cellular fraction with cancer cells that were cultured for 7-days at optimized conditions. The RCCS vessel instead yielded a (−)4.8-fold decrease in the CD133(+)cellular fraction respect to the HFB after 7-days of culture. Interestingly, we also found that the hypogravity environment of the HFB greatly sensitized the CD133(+) cancer cells, which are normally resistant to chemo treatment, to become susceptible to various chemotherapeutic agents, paving the way to less toxic and more effective chemotherapeutic treatment in patients. To be able to test the efficacy of cytotoxic agents in vitro prior to their use in clinical setting on cancer cells as well as on cancer stem cells may pave the way to more effective chemotherapeutic strategies in patients. This could be an important advancement in the therapeutic options of oncologic patients, allowing for more targeted and personalized chemotherapy regimens as well as for higher response rates.

Eradication of therapy-resistant human prostate tumors using an ultrasound-guided site-specific cancer terminator virus delivery approach

Intratumoral injections of a replication-incompetent adenovirus (Ad) expressing melanoma differentiation-associated gene-7/interleukin-24 (Ad.mda-7), a secreted cytokine displaying cancer-selective, apoptosis-inducing properties, profoundly inhibits prostate cancer (PC) growth in immune-incompetent animals. In contrast, Ad.mda-7 is ineffective in PCs overexpressing antiapoptotic proteins such as Bcl-2 or Bcl-x(L). However, intratumoral injections of a conditionally replication-competent Ad (CRCA) in which expression of the adenoviral E1A gene is driven by the cancer-specific promoter of progression-elevated gene-3 (PEG-3) and which simultaneously expresses mda-7/interleukin (IL)-24 in the E3 region of the Ad (Ad.PEG-E1A-mda-7), a cancer terminator virus (CTV), is highly active in these cells. A major challenge for gene therapy is systemic delivery of nucleic acids directly into an affected tissue. Ultrasound (US) contrast agents (microbubbles-MBs) are viable candidates for gene delivery/therapy. Here, we show that MB/Ad.mda-7 complexes targeted to DU-145 cells using US dramatically reduced tumor burden in xenografted nude mice. Additionally, US-guided MB/CTV delivery completely eradicated not only targeted DU-145/Bcl-x(L)-therapy-resistant tumors, but also nontargeted distant tumors (established in the opposite flank), thereby implementing a cure. These findings highlight potential therapeutic applications of this novel image-guided gene therapy technology for advanced PC patients with metastatic disease.

Ultrasound guided site specific gene delivery system using adenoviral vectors and commercial ultrasound contrast agents

We have evaluated if ultrasound imaging (US) and various commercially available contrast microbubbles can serve as a non-invasive systemically administered delivery vehicle for site-specific adenoviral-mediated gene transfer in vitro and in vivo. The contrast agents were tested for their ability to enclose and to protect an adenoviral vector carrying the GFP marker gene (Ad-GFP) into the microbubbles. We have also evaluated the ability of the innate immune system to inactivate free adenoviruses as well as unenclosed viruses adsorbed on the surface of the contrast agents and in turn the ability of the microbubbles to enclose and to protect the viral vectors from such agents. In vitro as well as in vivo, innate components of the immune system were able to serve as inactivating agents to clear free viral particles and unenclosed adenoviruses adsorbed on the microbubbles' surface. Systemic delivery of Ad-GFP enclosed into microbubbles in the tail vein of nude mice resulted in specific targeting of the GFP transgene. Both fluorescence microscopy and GFP immunohistochemistry demonstrated US guided specific transduction in the targeted cells only, with no uptake in either heart, lungs or liver using complement-pretreated Ad-GFP microbubbles. This approach enhances target specificity of US microbubble destruction as a delivery vehicle for viral-mediated gene transfer.

Expression of cell cycle-regulated proteins pRB2/p130, p107, E2F4, p27, and pCNA in salivary gland tumors: prognostic and diagnostic implications

The retinoblastoma family consists of the tumor suppressor nuclear phosphoprotein pRb/p105 and related proteins p107 and pRb2/p130. Recent immunohistochemical studies of the retinoblastoma family of proteins in lung and endometrial cancer and choroidal melanomas show a tight inverse correlation between the histologic grading in the most aggressive tumor types and pRb2/p130 expression. This led us to investigate the role of pRb2/p130 in salivary tumors. We studied the expression of pRb2/p130, p107, E2F4, p27, and PcNA by immunohistochemistry in a panel of 44 salivary gland tumors. We found a direct correlation between the cytoplasmic expression of pRb2/p130 and tumor grading and the presence of metastasis that was highly statistically significant (P < 0.001). Additionally, increased cytoplasmic pRb2/p130 expression was significantly correlated with a decreased probability of survival (P < 0.001). Interestingly, p107 nuclear expression showed a strong direct correlation when compared with the same variables. pRb2/p130 showed the highest percentage of undetectable nuclear levels in the specimens examined and the tightest inverse correlation (P < 0.0001) with both the histologic grading and pCNA expression in malignant salivary tumors. Additionally, E2F4 showed an identical localization pattern as to that of pRb2/p130. These data suggests an important role for pRb2/p130 in the pathogenesis and progression of certain salivary gland cancers.

Osmotic stimulation of the Na+/H+ exchanger NHE1: relationship to the activation of three MAPK pathways

The Na+/H+ exchanger (NHE) becomes activated by hyperosmolar stress, thereby contributing to cell volume regulation. The signaling pathway(s) responsible for the shrinkage-induced activation of NHE, however, remain unknown. A family of mitogen-activated protein kinases (MAPK), encompassing p42/p44 Erk, p38 MAPK and SAPK, has been implicated in a variety of cellular responses to changes in osmolarity. We therefore investigated whether these kinases similarly signal the hyperosmotic activation of NHE. The time course and osmolyte concentration dependence of hypertonic activation of NHE and of the three sub-families of MAPK were compared in U937 cells. The temporal course and dependence on osmolarity of Erk and p38 MAPK activation were found to be similar to that of NHE stimulation. However, while pretreatment of U937 cells with the kinase inhibitors PD98059 and SB203580 abrogated the osmotic activation of Erk and p38 MAPK, respectively, it did not prevent the associated stimulation of NHE. Thus, Erk1/2 and/or p38 MAPK are unlikely to mediate the osmotic regulation of NHE. The kinetics of NHE activation by hyperosmolarity appeared to precede SAPK activation. In addition, hyperosmotic activation of NHE persisted in mouse embryonic fibroblasts lacking SEK1/MKK4, an upstream activator of SAPK. Moreover, shrinkage-induced activation of NHE still occurred in COS-7 cells that were transiently transfected with a dominant-negative form of SEK1/MKK4 (SEK1/MKK4-A/L) that is expected to inhibit other isoforms of SEK as well. Together, these results demonstrate that the stimulation of NHE and the activation of Erk, p38 MAPK and SAPK are parallel but independent events.

Light adaptation: night vision goggle effect on cockpit instrument reading time

BACKGROUND

Light adaptation to the intensified image provided by a night vision device may handicap pilots who have set cockpit instrument luminance too low.

METHODS

Under conditions simulating night flying, subjects adapted to an NVG image at 3 or 10 footlamberts (fL), then used a joystick to indicate the position of the horizon in an ADI illuminated by NVIS-compatible light at luminances 2 to 3.5 log units lower than the NVG image.

RESULTS

Response times increased no more than a few tenths of a second when the decrease in luminance was only 2 log units. Greater decreases produced correspondingly longer delays in response, reaching as much as 5.5 s for subjects in their twenties and 8-15 s for older subjects.

CONCLUSIONS

While a decrease of more than 2 log units is not likely to occur under most operational conditions, it is certainly possible, and pilots should be aware that significant risk can be incurred by setting cockpit instruments to luminance levels below 0.03 fL.

Time course of early mesopic adaptation to luminance decrements and recovery of spatial resolution

The time course of recovery of spatial resolution following adaptation to a uniform field was measured for test probes presented at lower illuminance than the adapting field. Six observers were tested in a Maxwellian-view system using 20 degrees adapting fields of 1.6-2.6 log photopic trolands. Test stimuli were 7 degrees, 250 ms Gabor patches (1 and 6 cpd) of mean retinal illuminance 2-3 log units lower than the adapting field. During the 9 s after adapting field offset, contrast thresholds for orientation discrimination followed an exponential-decay function and showed longer recovery times for larger illuminance decrements and higher spatial frequency.

RB2/p130 gene-enhanced expression down-regulates vascular endothelial growth factor expression and inhibits angiogenesis in vivo

Angiogenesis is an essential step in the progression of tumor formation and development. The switch to an angiogenetic phenotype can occur as a distinct step before progression to a neoplastic phenotype and is linked to genetic changes such as mutations in key cell cycle regulatory genes. The pathogenesis of the angiogenetic phenotype may involve the inactivation of tumor suppressor genes such as the "guardian of the genome," p53, and the cyclin-dependent kinase inhibitor p16. Retinoblastoma family member RB2/p130 encodes a cell cycle regulatory protein and has been found mutated in different tumor types. Overexpression of RB2/p130 not only suppresses tumor formation in nude mice but also causes regression of established tumor grafts, suggesting that RB2/p130 may modulate the angiogenetic balance. We found that induction of RB2/p130 expression using a tetracycline-regulated gene expression system as well as retroviral and adenoviral-mediated gene delivery inhibited angiogenesis in vivo. This correlated with pRb2/p130-mediated down-regulation of vascular endothelial growth factor protein expression both in vitro and in vivo.

Heterotrisomy, a significant contributing factor to ventricular septal defect associated with Down syndrome?

Down syndrome (DS; trisomy 21) is associated with a wide range of variable clinical features, one of the most common being congenital heart defects (CHD). We used molecular genetic techniques to study the inheritance of genes on chromosome 21 in children with DS and CHD. Polymorphic markers on the long arm of chromosome 21 were analysed in 99 families who had a child with DS. Of these, 60 children had a CHD and 39 children had no CHD. Heterotrisomy describes the inheritance of an allele from each of three different grandparents. In some cases heterotrisomy will involve the inheritance of three different alleles. Heterotrisomic regions were defined as those showing retention of non-disjoining parental heterozygosity at polymorphic loci in the non-disjoined chromosomes of children with DS. Using polymorphic non-coding markers, we identified a consistent 9.6-cM minimum region (D21S167-HMG14) of heterotrisomy in children with DS and ventricular septal defect (VSD). Comparing individuals with DS and VSD to all others with DS (those either with no CHD or with any other CHD combined) shows the individuals with DS and VSD to have significantly more non-reduction or heterotrisomy in this region (P=0.006, Fisher's exact test, two-tailed). We postulate that heterotrisomy for a gene or genes in this region is a contributing factor to the pathogenesis of VSD in trisomy 21 either through the presence of three different specific alleles or through the presence of specific combinations of alleles.

A serine 37 mutation associated with two missense mutations at highly conserved regions of p53 affect pro-apoptotic genes expression in a T-lymphoblastoid drug resistant cell line

The p53 protein accumulates rapidly through post-transcriptional mechanisms following cellular exposure to DNA damaging agents and is also activated as a transcription factor leading to growth arrest or apoptosis. Phosphorylation of p53 occurs after DNA damage thereby modulating its activity and impeding the interaction of p53 with its negative regulator oncogene Mdm2. The serines 15 and 37 present in the amino terminal region of p53 are phosphorylated by the DNA-dependent protein kinase (DNA-PK) in response to DNA damage. In order to verify if specific p53 mutations occur in the multi-drug resistance phenotype, we analysed the p53 gene in two T-lymphoblastoid cell lines, CCRF-CEM and its multi-drug-resistant clone CCRF-CEM VLB100, selected for resistance to vinblastine sulfate and cross-resistant to other cytotoxic drugs. Both cell lines showed two heterozygous mutations in the DNA binding domain at codons 175 and 248. The multi-drug resistant cell line, CCRF-CEM VLB100, showed an additional mutation that involves the serine 37 whose phosphorylation is important to modulate the protein activity in response to DNA damage. The effects of these mutations on p53 transactivation capacity were evaluated. The activity of p53 on pro-apoptotic genes expression in response to DNA damage induced by (-irradiation, was affected in the vinblastine (VLB) resistant cell line but not in CCRF-CEM sensitive cell line resulting in a much reduced apoptotic cell death of the multi-drug resistant cells.

Inducible pRb2/p130 expression and growth-suppressive mechanisms: evidence of a pRb2/p130, p27Kip1, and cyclin E negative feedback regulatory loop

The retinoblastoma family of proteins, pRb/p105, p107, and pRb2/ p130, cooperate to regulate cell cycle progression through the G1 phase of the cell cycle. Each of the family members realize their common goal of G1-S checkpoint regulation through overlapping and unique growth regulatory pathways. We took advantage of a tetracycline-regulated gene expression system to control the expression of RB2/p130 in JC virus-induced hamster brain tumor cells to study in vivo the molecular mechanisms used by pRb2/p130 to elicit its growth-suppressive function. We have previously used this system to demonstrate that induction of pRb/ p130 expression suppresses tumor growth in vivo by overcoming neoplastic transformation mediated by the large T-antigen oncoprotein of JCV (JCV TAg). Here we found that induction of pRb2/p130 in vivo specifically inhibits cyclin A- and cyclin E-associated kinase activity and by doing so induces p27Kip1 levels presumably by inhibiting p27Kip1-targeted proteolysis by cyclin E-Cdk2 phosphorylation of p27Kip1. RB2/p130 induction also decreased cyclin A and the transcription factor E2F-1 while increasing cyclin E at both the transcriptional and protein levels of expression. The growth inhibitory activity of pRb2/p130 also correlated with its E2F-binding capacity. Furthermore, p27Kip1 and pRb2/p130 were found to be targets of the JCV TAg oncoprotein and to interact in vivo with each other independently from the presence of TAg. Interestingly, pRb2/p130 expression negatively modulated the binding of p27Kip1 to JCV TAg. These data suggest that pRb2/p130 and p27Kip1 may cooperate in regulating cellular proliferation, and both may be involved in a negative feedback regulatory loop with cyclin E.

Genetic alterations disrupting the nuclear localization of the retinoblastoma-related gene RB2/p130 in human tumor cell lines and primary tumors

The prototypic tumor suppressor gene, the retinoblastoma gene (RB/ p105), is mutated in a variety of human tumors. However, to date, mutational data on retinoblastoma family members p107 and RB2/p130 in tumors is lacking. We studied the expression of pRb2/p130 by immunocytochemistry and Western blot analysis in a panel of human osteosarcoma and lymphoid cell lines. Only the lymphoid cell lines showed an abnormal cytoplasmic localization of pRb2/p130, suggesting possible alterations within the region of nuclear localization signaling. We screened these cell lines for genetic alterations of the RB2/p130 gene in the region of the putative bipartite nuclear localization signal (NLS). This region is highly homologous with that of the RB/p105 gene. In addition, we screened four primary Burkitt's lymphomas for genetic alterations in the RB2/p130 gene. Naturally occurring mutations, which disrupt the putative bipartite NLS, were found in lymphoma cell lines and primary tumors, but not in the osteosarcoma cell lines, where normal nuclear localization of the protein was detectable. Site-directed mutagenesis and transfection assay using NLS mutants displayed markedly reduced biological activity as measured by flow cytometric analysis. This study clearly describes RB2/ p130 as an important target for mutations and subsequent inactivation in lymphoma pathogenesis, thus validating that RB2/p130 is a classical tumor suppressor gene.