Exosc9 Initiates SUMO-Dependent lncRNA TERRA Degradation to Impact Telomeric Integrity in Endocrine Therapy Insensitive Hormone Receptor-Positive Breast Cancer

Long, noncoding RNAs (lncRNAs) are indispensable for normal cell physiology and, consequently, are tightly regulated in human cells. Yet, unlike mRNA, substantially less is known about the mechanisms for lncRNA degradation. It is important to delineate the regulatory control of lncRNA degradation, particularly for lncRNA telomeric repeat-containing RNA (TERRA), as the TERRA-telomere R-loops dictate cell cycle progression and genomic stability. We now report that the exosome complex component Exosc9 degrades lncRNA TERRA in human mammary epithelial cells. Heterochromatin protein 1 alpha (HP1α) recruits Exosc9 to the telomeres; specifically, the SUMO-modified form of HP1α supports interaction with Exosc9 and, as previously reported, lncRNA TERRA. The telomeric enrichment of Exosc9 is cell cycle-dependent and consistent with the loss of telomeric TERRA in the S/G2 phase. Elevated Exosc9 is frequently observed and drives the growth of endocrine therapy-resistant (ET-R) HR+ breast cancer (BCa) cells. Specifically, the knockdown of Exosc9 inversely impacts telomeric R-loops and the integrity of the chromosome ends of ET-R cells. Consistently, Exosc9 levels dictate DNA damage and the sensitivity of ET-R BCa cells to PARP inhibitors. In this regard, Exosc9 may serve as a promising biomarker for predicting the response to PARP inhibitors as a targeted monotherapy for ET-R HR+ BCa.

Objective Analysis of Breast Symmetry in Female Patients Undergoing Breast Reconstruction After Total Mastectomy

Background

Satisfaction with the breast aesthetic outcome is an expectation of breast reconstruction surgery, which is an integral part of cancer treatment for many patients. We evaluated postreconstruction breast symmetry in 82 female patients using distance and volume measurements.

Objectives

Clinical factors, such as reconstruction type (implant-based and autologous reconstruction), laterality, timing of reconstruction (immediate, delayed, and sequential), radiation therapy (RT), and demographic factors (age, BMI, race, and ethnicity), were evaluated as predictors of postoperative symmetry. Matched preoperative and postoperative measurements for a subset of 46 patients were used to assess correlation between preoperative and postoperative symmetry.

Methods

We used standardized differences between the left and right breasts for the sternal notch to lowest visible point distance and breast volume as metrics for breast, positional symmetry, and volume symmetry, respectively. We performed statistical tests to compare symmetry between subgroups of patients based on reconstruction type, laterality, timing, RT, and demographics.

Results

Overall, reconstruction type, reconstruction timing, and RT were observed to be factors significantly associated with postoperative symmetry, with implant reconstructions and immediate reconstruction procedures, and no RT showing better postoperative breast volume symmetry. Subgroup analyses, for both reconstruction type and laterality, showed superior volume symmetry for the bilateral implant reconstructions. No correlation was observed between preoperative and postoperative breast symmetry. Demographic factors were not significant predictors of postreconstruction symmetry.

Conclusions

This comprehensive analysis examines multiple clinical factors in a single study and will help both patients and surgeons make informed decisions about reconstruction options at their disposal.

Level of Evidence 3

Breast Decisions: Recommender System for Appearance Counseling about Breast Reconstruction

Appearance counseling is an important component of the consent process for breast reconstruction. The purpose of appearance counseling is to help the patient form realistic expectations of what she might look like after breast reconstruction. In this article, we introduce a recommender system, "BreastDecisions," for appearance counseling that suggests photographs of previous patients that are tailored to a specific patient to help her form realistic expectations of her own reconstruction.

Methods

We present user specifications and algorithm parameters needed to incorporate the recommender system into the appearance counseling workflow. We demonstrate the system for a common counseling scenario using a knowledgebase of previous breast reconstruction patients. The medical appropriateness of the recommended photographs for use in appearance counseling was evaluated by experts using a four-point rating system.

Results

The recommender system presents photographs that are medically appropriate for counseling a specific patient, depicts typical outcomes, and adapts to a variety of clinical workflows. For each of 33 patients taken as examples of breast reconstruction patients, we used the system to identify photographs for appearance counseling. The baseline average medical appropriateness of the recommended photographs was between mostly appropriate (some explanation needed) and medically appropriate (minimal explanation needed). We demonstrate filtering and ranking steps to reduce the number of recommended photographs and increase the average medical appropriateness.

Conclusions

Our recommender system automatically suggests photographs of previous breast reconstruction patients for use in counseling a patient about appearance outcomes. The system is patient-specific and customizable to a particular surgeon's practice.

Potential of Intraoperative 3D Photography and 3D Visualization in Breast Reconstruction

Although pre- and postoperative three-dimensional (3D) photography are well-established in breast reconstruction, intraoperative 3D photography is not. We demonstrate the process of intraoperative acquisition and visualization of 3D photographs for breast reconstruction and present clinicians' opinions about intraoperative visualization tools.

METHODS

Mastectomy specimens were scanned with a handheld 3D scanner during breast surgery. The 3D photographs were processed to compute morphological measurements of the specimen. Three visualization modalities (screen-based viewing, augmented reality viewing, and 3D printed models) were created to show different representations of the 3D photographs to plastic surgeons. We interviewed seven surgeons about the usefulness of the visualization methods.

RESULTS

The average time for intraoperative acquisition of 3D photographs of the mastectomy specimen was 4 minutes, 8 seconds ± 44 seconds. The average time for image processing to compute morphological measurements of the specimen was 54.26 ± 40.39 seconds. All of the interviewed surgeons would be more inclined to use intraoperative visualization if it displayed information that they are currently missing (eg, the target shape of the reconstructed breast mound). Additionally, the surgeons preferred high-fidelity visualization tools (such as 3D printing) that are easy-to-use and have minimal disruption to their current workflow.

CONCLUSIONS

This study demonstrates that 3D photographs can be collected intraoperatively within acceptable time limits, and quantitative measurements can be computed timely to be utilized within the same procedure. We also report surgeons' comments on usability of visualization methods and of measurements of the mastectomy specimen, which can be used to guide future surgical practice.

Review of Quantitative Imaging for Objective Assessment of Fat Grafting Outcomes in Breast Surgery

This article presents a comprehensive review of the use of quantitative measurements based on breast images to assess fat retention, breast aesthetics, and fat necrosis after autologous fat grafting. Breast volume measured from MRI and 3-dimensional surface images is widely used as a measure of fat retention. Breast aesthetics are assessed from a combination of anthropometric (distance and contour) measurements on breast surface images. Examination of radiologic images (ultrasonography, mammography, and MRI) is utilized to assess fat necrosis. The article discusses implementation guidelines for objective outcome assessment to support robust quantification and enable investigations of fat grafting efficacy. Level of Evidence: 4.

Abstract PS1-24: Symmetry of breasts following reconstructive surgery

INTRODUCTION

Breast reconstruction surgery is an integral part of breast cancer treatment that aims to restore breast appearance after mastectomy. We assessed breast symmetry following breast reconstruction using measures of distance and volume.

MATERIAL AND METHODS

Patients undergoing breast reconstruction surgery were enrolled in an IRB approved study from 2011 to 2014 at The University of Texas MD Anderson Cancer Center. We utilized pre- and post-operative 3D surface images (3dMDtorso, 3dMD LLC, Atlanta, GA) from 53 women who had completed the breast reconstruction process (83% at 18 months (M), 9.4% at 12M and 7.6% at 9M). Patients provided approved consent. Thirty-six women had bilateral and 17 had unilateral surgery. Eleven patients in the unilateral group had symmetry surgery on the contralateral breast (5 had mastopexy, 4 had reduction, 1 had augmentation, and 1 had augmentation and mastopexy). Within the bilateral group, 9 patients underwent autologous reconstruction, 21 received implants, and 6 had mixed (autologous and implant) procedures. Within the unilateral group, there were 10 implant and 7 autologous reconstructions. We measured the sternal notch (SN) to lowest visible point (LVP) distance and volume for each breast. Breast symmetry was assessed using 1) Difference between the left and right breasts for the SN-LVP distance and volume measures, 2) SN-LVP distance ratio and volume ratio computed using values for the left and right breast. The smaller value was divided by the larger, so that a ratio of 1.0 indicated perfect symmetry [1]. Differences < 5 mm for SN-LVP distance and < 50 cc for breast volume were used as indicators of symmetry [1].

RESULTS

Overall, pre-operatively 50.9% patients showed a SN-LVP difference < 5 mm compared to 35.9% post-operatively, whereas 43.4% showed a breast volume difference < 50 cc pre-operatively compared to 62.3% post-operatively.

Mean pre- and post-operative SN-LVP distance ratios were found to be 0.97 ± 0.03 and 0.96 ± 0.03, respectively, whereas the breast volume ratios were 0.91 ± 0.06 and 0.92 ± 0.08, respectively. Shapiro-Wilk tests showed non-normal distribution for both ratios; thus, non-parametric analysis was performed using Mann-Whitney U-test and, for matched pairs, the Wilcoxon Matched Pairs Sign-Ranked test. For both distance and volume ratios, we failed to reject the null hypothesis that the median of the paired differences between the pre- and post-operative values was zero. Also, no significant differences were found for both ratios when comparing autologous and implant-based surgeries. Bilateral reconstructions were compared to unilateral procedures that included a contralateral symmetry procedure. Significantly higher distance ratios (0.97 ± 0.03, median of 0.98, p = 0.005) were found for bilateral reconstructions compared to unilateral (0.94 ± 0.04, median of 0.94), but no differences in volume ratios were noted. Significant differences were noted for both distance (p = 0.033) and volume (p = 0.009) ratios when comparing bilateral (distance: 0.96 ± 0.02, median of 0.97 and volume: 0.96 ± 0.03, median of 0.97) to unilateral implant-based reconstructions (distance: 0.93 ± 0.04, median of 0.94 and volume: 0.91 ± 0.05, median of 0.90), but no difference in symmetry was found between unilateral and bilateral autologous reconstructions.

CONCLUSION

Distance symmetry was noted in a higher percentage of the pre-operative population compared to post-operative, whereas a larger proportion of the post-operative patients showed volume symmetry compared to the pre-operative group. Implant-based bilateral procedures showed improved symmetry compared to the unilateral procedures.

REFERENCES

1.Cheong AL, Liu J, Reece GP, Nicklaus KM, Bordes MC, Hanson SE, Markey MK, Merchant, FA “Natural Breast Symmetry in Preoperative Breast Cancer Patients”, Plastic and Reconstructive Surgery - Global Open: 2019;7(7):e2297.

Citation Format: Thao Bui, Urmila Sampathkumar, Zhale Nowroozilarki, Jun Liu, Mary Catherine Borders, Summer E Hanson, Gregory P Reece, Mia K Markey, Fatima A Merchant. Symmetry of breasts following reconstructive surgery [abstract]. In: Proceedings of the 2020 San Antonio Breast Cancer Virtual Symposium; 2020 Dec 8-11; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2021;81(4 Suppl):Abstract nr PS1-24.

Goldilocks Principle: Preference for Change in Breast Size in Breast Cancer Reconstruction Patients

Patients' preferences regarding changing or maintaining their breast size after mastectomy and reconstruction are important but understudied determinants of post-surgical satisfaction and quality of life. The goal of this study was to identify factors associated with preferences for changing or maintaining breast size for women undergoing breast reconstruction at The University of Texas MD Anderson Cancer Center in the United States from 2011 to 2014. The average age of participants was 45.7 ± 9.1 years. At baseline, mean average breast volumes were 755.7 ± 328.4 mL for all women (n = 48), 492.3 mL ± 209.3 for 13 women who preferred to be "bigger than now," 799.2 mL ± 320.9 for 25 women who preferred to remain "about the same," and 989.3 mL ± 253.1 for 10 women who preferred "smaller than now." Among the 23 women who preferred to change their breast size, 19 desired to shift toward the mean. Women with the smallest and largest 20% of baseline breast size were more likely to desire a change toward the mean (p = 0.006). Multinomial logistic regression models found average breast volume and satisfaction with breast size to be the most important factors associated with preferences for changing or maintaining breast size for women undergoing breast reconstruction. This study provides preliminary evidence for a "Goldilocks principle" in women's preferences for breast size change in the context of breast reconstruction, and identifies hypotheses for future studies of the associations among preference for change in breast size, preference achievement, and post-reconstruction body image.

Multifunctional Bio-Nanocomposite Coatings for Perishable Fruits

Hunger and chronic undernourishment impact over 800 million people, which translates to ≈10.7% of the world's population. While countries are increasingly making efforts to reduce poverty and hunger by pursuing sustainable energy and agricultural practices, a third of the food produced around the globe still is wasted and never consumed. Reducing food shortages is vital in this effort and is often addressed by the development of genetically modified produce or chemical additives and inedible coatings, which create additional health and environmental concerns. Herein, a multifunctional bio-nanocomposite comprised largely of egg-derived polymers and cellulose nanomaterials as a conformal coating onto fresh produce that slows down food decay by retarding ripening, dehydration, and microbial invasion is reported. The coating is edible, washable, and made from readily available inexpensive or waste materials, which makes it a promising economic alternative to commercially available fruit coatings and a solution to combat food wastage that is rampant in the world.

Abstract P5-16-15: 3D symmetry of pre-operative breasts in cancer patients

INTRODUCTION

Achieving breast symmetry and mitigating ptosis are important aims of cosmetic and reconstructive breast surgery. Breast asymmetry typically occurs when the left and right breasts differ in size, shape, or position. A few studies have associated breast asymmetry to hormonal changes and breast cancer risk. Similarly, changes in breast ptosis have been attributed to age, BMI, breast volume, smoking history, pregnancy, and weight loss. The purpose of this study is to provide normative data and understand factors that may attribute to breast asymmetry and ptosis.

MATERIAL AND METHODS

The dataset consisted of 87 surface images of women scheduled to undergo mastectomy for the prevention or treatment of breast cancer. Patients were enrolled in an IRB approved research study from 2011 to 2014 at MD Anderson Cancer Center (Houston, TX). Images were obtained using 3dMDTorso (3dMD LLC, Atlanta, GA). Patient demographics were recorded and tumor size was obtained from MD Anderson Breast Cancer Management System, and tumor location data were obtained through a search of the MD Anderson Tumor Registry Database. Patients with a BMI > 41, rare congenital breast abnormalities, radiation therapy, or major breast surgeries were excluded. Breast symmetry was assessed by computing the ratio of the sternal notch (SN) to nipple (N) distance and breast volume ratio of the left and right breasts. Perfect symmetry occurs when the ratio is one. The smaller breast was evaluated over the larger breast so that ratios were less than one. A plastic surgeon rated each breast for ptosis. The correlation between age, BMI, and symmetry parameters were assessed using Pearson's r, Spearman's rho, and Kendall's tau coefficients. A multivariable linear model was used to evaluate the association between the ratios and demographic factors. A multiple ordinal logistic regression analysis was performed for age, BMI, and breast volume against ptosis.

RESULTS

The average sternal notch to nipple (SN-N) distance was 24.1 ± 3.30 cm and the SN-N ratio was 0.975 ± 0.020. The average breast volume was 794 ± 323 cc and the breast volume ratio was 0.914 ± 0.065. When comparing the right and left breasts, for SN-N distances, we found that 58.6% of the patients had a difference of less than 5 mm, 17.3% of the patients had a difference between 5 and 10 mm, and 24.1% of the patients had a difference greater than 10 mm. For volume, 49.4% of the patients had less than 50 cc of difference, 21.5% of the patients had a difference between 50 and 100 cc, and 29.1% of the patients differed by more than 100 cc. Tumor size did not significantly affect breast volume based on the t-test (p = 0.181). Symmetry ratios did not show significant correlation with age or BMI. Age and BMI were also not significantly associated with ptosis (p>0.05), but larger breast volumes were associated with increasing degree of ptosis (OR: 1.14; 95% CI: 1.06-1.22; p<0.001).

CONCLUSION

Our findings indicate that larger breast volumes are associated with increased ptosis grade. Age and BMI did not appear to significantly impact asymmetry or ptosis.

Citation Format: Nicklaus KM, Cheong AL, Liu J, Reece GP, Bordes MC, Hanson SE, Markey MK, Merchant FA. 3D symmetry of pre-operative breasts in cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P5-16-15.

Abstract P5-18-03: Relationships among breast symmetry, appearance investment, and body image dissatisfaction in breast cancer patients undergoing reconstruction

Purpose: Reconstruction as part of treatment for breast cancer is aimed at mitigating body image concerns post-mastectomy. Although algorithms are increasingly being developed to objectively assess breast reconstruction outcomes, previous research has not evaluated associations between objectively quantified breast aesthetic appearance and patient-reported body image outcomes. Further, the role appearance investment plays in a patient's body image is not well understood. We examined the extent to which objectively quantified breast symmetry and appearance investment were associated with body image dissatisfaction in patients undergoing cancer-related breast reconstruction. Method: Breast cancer patients in different stages of reconstruction (n=190) completed self-report measures of appearance investment and body image dissatisfaction. Vertical extent and horizontal extent symmetry values, which are indicators of breast symmetry across the vertical axis, were calculated from clinical photographs. Associations among symmetry, appearance investment, body image dissatisfaction, and patient clinical factors were examined. Multiple regression was used to evaluate the association of symmetry and appearance investment with body image dissatisfaction. Results: Vertical extent symmetry, but not horizontal extent symmetry, was associated with body image dissatisfaction. Multiple regression results indicated that decreased vertical extent symmetry (β = -0.24, p <0.01) and increased appearance investment (β = 0.37, p <0.001) were significantly associated with greater body image dissatisfaction while controlling for clinical factors.Conclusions: Our findings suggest that quantitatively measured reconstruction outcomes and appearance investment both significantly contribute to an understanding of patient-reported body image satisfaction during breast reconstruction treatment. Future studies are encouraged to utilize algorithms assessing breast aesthetic appearance and to consider patient values as predictors of body image outcomes.

Symmetry Predicting Body Image Dissatisfaction Controlling for Clinical Factors Body Image Dissatisfaction (β)VE Symmetry-0.24**Appearance investment (ASI-R)0.37*** Clinial factors controlled for BMI-0.01Prior chemotherapy0.19Prior radiation therapy0.08Prior complications0.06Reconstruction timing (ref: Immediate) Delayed0.06Reconstruction type (ref: Implant) Autologous-0.01Mixed type0.09Reconstruction Stage (ref: Pre-surgery) Intermediate-0.06Final-0.15*p<.05, **p<.01, ***p<.001; ref = reference group; Note ASI-R = Appearance Schemas Inventory-Revised

Citation Format: Nicklaus KM, Teo I, Reece GP, Huang S-C, Mahajan K, Andon J, Khanal P, Sun CS, Merchant FA, Markey MK, Fingeret MC. Relationships among breast symmetry, appearance investment, and body image dissatisfaction in breast cancer patients undergoing reconstruction [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-18-03.

Transcriptional regulation of core autophagy and lysosomal genes by the androgen receptor promotes prostate cancer progression

AR (androgen receptor) signaling is crucial for the development and maintenance of the prostate as well as the initiation and progression of prostate cancer. Despite the AR's central role in prostate cancer progression, it is still unclear which AR-mediated processes drive the disease. Here, we identified 4 core autophagy genes: ATG4B, ATG4D, ULK1, and ULK2, in addition to the transcription factor TFEB, a master regulator of lysosomal biogenesis and function, as transcriptional targets of AR in prostate cancer. These findings were significant in light of our recent observation that androgens promoted prostate cancer cell growth in part through the induction of autophagy. Expression of these 5 genes was essential for maximal androgen-mediated autophagy and cell proliferation. In addition, expression of each of these 5 genes alone or in combination was sufficient to increase prostate cancer cell growth independent of AR activity. Further, bioinformatic analysis demonstrated that the expression of these genes correlated with disease progression in 3 separate clinical cohorts. Collectively, these findings demonstrate a functional role for increased autophagy in prostate cancer progression, provide a mechanism for how autophagy is augmented, and highlight the potential of targeting this process for the treatment of advanced prostate cancer.

Identification of vascular disruptor compounds by analysis in zebrafish embryos and mouse embryonic endothelial cells

To identify vascular disruptor compounds (VDCs), this study utilized an in vivo zebrafish embryo vascular model in conjunction with a mouse endothelial cell model to screen a subset of the U.S. Environmental Protection Agency (EPA) ToxCast Phase I chemical inventory. In zebrafish, 161 compounds were screened and 34 were identified by visual inspection as VDCs, of which 28 were confirmed as VDCs by quantitative image analysis. Testing of the zebrafish VDCs for their capacity to inhibit endothelial tube formation in the murine yolk-sac-derived endothelial cell line C166 identified 22 compounds that both disrupted zebrafish vascular development and murine endothelial in vitro tubulogenesis. Putative molecular targets for the VDCs were predicted using EPA's Toxicological Prioritization Index tool and a VDC signature based on a proposed adverse outcome pathway for developmental vascular toxicity. In conclusion, our screening approach identified 22 novel VDCs, some of which were active at nanomolar concentrations.

Inferior Breast-Chest Contour Detection in 3-D Images of the Female Torso

Stereophotogrammetry is finding increased use in clinical breast surgery, both for breast reconstruction after oncological procedures and cosmetic augmentation and reduction. The ability to visualize and quantify morphological features of the breast facilitates pre-operative planning and post-operative outcome assessment. The contour outlining the lower half of the breast is important for the quantitative assessment of breast aesthetics. Based on this inferior breast contour, relevant morphological measures, such as breast symmetry, volume, and ptosis, can be determined. In this paper, we present an approach for automatically detecting the inferior contour of the breast in 3D images. Our approach employs surface curvature analysis and is able to detect the breast contour with high accuracy, achieving an average error of 1.64 mm and a dice coefficient in the range of 0.72–0.87 when compared with the manually annotated contour (ground truth). In addition, the detected contour is used to facilitate the detection of the lowest visible point on the breast, which is an important landmark for breast morphometric analysis.

Computation of breast ptosis from 3D surface scans of the female torso

Stereophotography is now finding a niche in clinical breast surgery, and several methods for quantitatively measuring breast morphology from 3D surface images have been developed. Breast ptosis (sagging of the breast), which refers to the extent by which the nipple is lower than the inframammary fold (the contour along which the inferior part of the breast attaches to the chest wall), is an important morphological parameter that is frequently used for assessing the outcome of breast surgery. This study presents a novel algorithm that utilizes three-dimensional (3D) features such as surface curvature and orientation for the assessment of breast ptosis from 3D scans of the female torso. The performance of the computational approach proposed was compared against the consensus of manual ptosis ratings by nine plastic surgeons, and that of current 2D photogrammetric methods. Compared to the 2D methods, the average accuracy for 3D features was ~13% higher, with an increase in precision, recall, and F-score of 37%, 29%, and 33%, respectively. The computational approach proposed provides an improved and unbiased objective method for rating ptosis when compared to qualitative visualization by observers, and distance based 2D photogrammetry approaches.

Automated analysis of zebrafish images for screening toxicants

An important factor facilitating the application of zebrafish in biomedical research is high throughput screening of vertebrate animal models. For example, being able to model the growth of blood vessel in the vasculature system is interesting for understanding both the circulatory system in humans, and for facilitating large scale screening of the influence of various chemicals on vascular development. Compared to other models, the zebrafish embryo is an attractive alternative for environmental risk assessment of chemicals since it offers the possibility to perform high-throughput analyses in vivo. However the lack of an automated image analysis framework restricts high throughput screening. In this paper, we provide a method for quantitative measurements of zebrafish blood vessel morphology since it is difficult to assess changes in vessel structure by visual inspection. The method presented is generalized, i.e. it is not restricted to any specific chemically treated zebrafish, and can be used with wide variety of chemicals.

Embryonic exposure to sodium arsenite perturbs vascular development in zebrafish

Exposure to arsenic in its inorganic form, arsenite, causes adverse effects to many different organs and tissues. Here, we have investigated arsenite-induced adverse effects on vascular tissues in the model organism zebrafish, Danio rerio. Zebrafish embryos were exposed to arsenite at different exposure windows and the susceptibility to vascular tissue damage was recorded at 72hours post fertilization (hpf). Intersegmental vessel sprouting and growth was most perturbed by exposure to arsenite during the 24-48hpf window, while disruption in the condensation of the caudal vein plexus was more often observed at the 48-72hpf exposure window, reflecting when these structures develop during normal embryogenesis. The vascular growth rate was decreased by arsenite exposure, and deviated from that of control embryos at around 24-26.5hpf. We further mapped changes in expression of key regulators of angiogenesis and vasculogenesis. Downregulation of vascular endothelial growth factor receptor 1/fms-related tyrosine kinase 1 (vegfr1/flt1) expression was evident already at 24hpf, coinciding with the decreased vascular growth rate. At later time points, matrix metalloproteinase 9 (mmp9) expression was upregulated, suggesting that arsenite affects the composition of the extracellular matrix. In total, the expression of eight key factors involved in different aspects of vascularization was significantly altered by arsenic exposure. In conclusion, our results show that arsenite is a potent vascular disruptor in the developing zebrafish embryo, a finding that calls for an evaluation of arsenite as a developmental vascular toxicant in mammalian model systems.

Regulation of the pentose phosphate pathway by an androgen receptor-mTOR-mediated mechanism and its role in prostate cancer cell growth

Cancer cells display an increased demand for glucose. Therefore, identifying the specific aspects of glucose metabolism that are involved in the pathogenesis of cancer may uncover novel therapeutic nodes. Recently, there has been a renewed interest in the role of the pentose phosphate pathway in cancer. This metabolic pathway is advantageous for rapidly growing cells because it provides nucleotide precursors and helps regenerate the reducing agent NADPH, which can contribute to reactive oxygen species (ROS) scavenging. Correspondingly, clinical data suggest glucose-6-phosphate dehydrogenase (G6PD), the rate-limiting enzyme of the pentose phosphate pathway, is upregulated in prostate cancer. We hypothesized that androgen receptor (AR) signaling, which plays an essential role in the disease, mediated prostate cancer cell growth in part by increasing flux through the pentose phosphate pathway. Here, we determined that G6PD, NADPH and ribose synthesis were all increased by AR signaling. Further, this process was necessary to modulate ROS levels. Pharmacological or molecular inhibition of G6PD abolished these effects and blocked androgen-mediated cell growth. Mechanistically, regulation of G6PD via AR in both hormone-sensitive and castration-resistant models of prostate cancer was abolished following rapamycin treatment, indicating that AR increased flux through the pentose phosphate pathway by the mammalian target of rapamycin (mTOR)-mediated upregulation of G6PD. Accordingly, in two separate mouse models of Pten deletion/elevated mTOR signaling, Pb-Cre;Pten(f/f) and K8-CreER(T2);Pten(f/f), G6PD levels correlated with prostate cancer progression in vivo. Importantly, G6PD levels remained high during progression to castration-resistant prostate cancer. Taken together, our data suggest that AR signaling can promote prostate cancer through the upregulation of G6PD and therefore, the flux of sugars through the pentose phosphate pathway. Hence, these findings support a vital role for other metabolic pathways (that is, not glycolysis) in prostate cancer cell growth and maintenance.

Combinational targeting offsets antigen escape and enhances effector functions of adoptively transferred T cells in glioblastoma

Preclinical and early clinical studies have demonstrated that chimeric antigen receptor (CAR)-redirected T cells are highly promising in cancer therapy. We observed that targeting HER2 in a glioblastoma (GBM) cell line results in the emergence of HER2-null tumor cells that maintain the expression of nontargeted tumor-associated antigens. Combinational targeting of these tumor-associated antigens could therefore offset this escape mechanism. We studied the single-cell coexpression patterns of HER2, IL-13Rα2, and EphA2 in primary GBM samples using multicolor flow cytometry and immunofluorescence, and applied a binomial routine to the permutations of antigen expression and the related odds of complete tumor elimination. This mathematical model demonstrated that cotargeting HER2 and IL-13Rα2 could maximally expand the therapeutic reach of the T cell product in all primary tumors studied. Targeting a third antigen did not predict an added advantage in the tumor cohort studied. We therefore generated bispecific T cell products from healthy donors and from GBM patients by pooling T cells individually expressing HER2 and IL-13Rα2-specific CARs and by making individual T cells to coexpress both molecules. Both HER2/IL-13Rα2-bispecific T cell products offset antigen escape, producing enhanced effector activity in vitro immunoassays (against autologous glioma cells in the case of GBM patient products) and in an orthotopic xenogeneic murine model. Further, T cells coexpressing HER2 and IL-13Rα2-CARs exhibited accentuated yet antigen-dependent downstream signaling and a particularly enhanced antitumor activity.

Automated Identification of Fiducial Points on 3D Torso Images

Breast reconstruction is an important part of the breast cancer treatment process for many women. Recently, 2D and 3D images have been used by plastic surgeons for evaluating surgical outcomes. Distances between different fiducial points are frequently used as quantitative measures for characterizing breast morphology. Fiducial points can be directly marked on subjects for direct anthropometry, or can be manually marked on images. This paper introduces novel algorithms to automate the identification of fiducial points in 3D images. Automating the process will make measurements of breast morphology more reliable, reducing the inter- and intra-observer bias. Algorithms to identify three fiducial points, the nipples, sternal notch, and umbilicus, are described. The algorithms used for localization of these fiducial points are formulated using a combination of surface curvature and 2D color information. Comparison of the 3D co-ordinates of automatically detected fiducial points and those identified manually, and geodesic distances between the fiducial points are used to validate algorithm performance. The algorithms reliably identified the location of all three of the fiducial points. We dedicate this article to our late colleague and friend, Dr. Elisabeth K. Beahm. Elisabeth was both a talented plastic surgeon and physician-scientist; we deeply miss her insight and her fellowship.

Androgens promote prostate cancer cell growth through induction of autophagy

Androgens regulate both the physiological development of the prostate and the pathology of prostatic diseases. However, the mechanisms by which androgens exert their regulatory activities on these processes are poorly understood. In this study, we have determined that androgens regulate overall cell metabolism and cell growth, in part, by increasing autophagy in prostate cancer cells. Importantly, inhibition of autophagy using either pharmacological or molecular inhibitors significantly abrogated androgen-induced prostate cancer cell growth. Mechanistically, androgen-mediated autophagy appears to promote cell growth by augmenting intracellular lipid accumulation, an effect previously demonstrated to be necessary for prostate cancer cell growth. Further, autophagy and subsequent cell growth is potentiated, in part, by androgen-mediated increases in reactive oxygen species. These findings demonstrate a role for increased fat metabolism and autophagy in prostatic neoplasias and highlight the potential of targeting underexplored metabolic pathways for the development of novel therapeutics.

3D imaging for quantitative assessment of toxicity on vascular development in zebrafish

In this study, we describe the utility of the zebrafish model of in-vivo blood vessel formation as a tool for chemical risk assessment. Time-lapse confocal imaging of embryonic vasculature in the zebrafish is used in conjunction with digital image analysis to monitor and quantify the effect of toxins on vascular development. Non-rigid registration is used to capture changes in vascular morphology over time. Vascular formation in healthy normal and arsenic treated embryos was evaluated for differences in vascular structure using the algorithms developed. Although, the temporal progression of vascular development was similar, significant differences were observed in vessel structure between the toxin treated and healthy fish. This study revealed, for the first time, that vital vascular structures in fish maybe affected by exposure to arsenic. This technique allowed visualization of vascular abnormalities in embryos showing no external signs of malformations.

3D Symmetry Measure Invariant to Subject Pose During Image Acquisition

In this study we evaluate the influence of subject pose during image acquisition on quantitative analysis of breast morphology. Three (3D) and two-dimensional (2D) images of the torso of 12 female subjects in two different poses; (1) hands-on-hip (HH) and (2) hands-down (HD) were obtained. In order to quantify the effect of pose, we introduce a new measure; the 3D pBRA (Percentage Breast Retraction Assessment) index, and validate its use against the 2D pBRA index. Our data suggests that the 3D pBRA index is linearly correlated with the 2D counterpart for both of the poses, and is independent of the localization of fiducial points within a tolerance limit of 7 mm. The quantitative assessment of 3D asymmetry was found to be invariant of subject pose. This study further corroborates the advantages of 3D stereophotogrammetry over 2D photography. Problems with pose that are inherent in 2D photographs are avoided and fiducial point identification is made easier by being able to panoramically rotate the 3D surface enabling views from any desired angle.

Validation of stereophotogrammetry of the human torso

The objective of this study was to determine if measurements of breast morphology computed from three-dimensional (3D) stereophotogrammetry are equivalent to traditional anthropometric measurements obtained directly on a subject using a tape measure. 3D torso images of 23 women ranged in age from 36 to 63 who underwent or were scheduled for breast reconstruction surgery were obtained using a 3dMD torso system (3Q Technologies Inc., Atlanta, GA). Two different types (contoured and line-of-sight distances) of a total of nine distances were computed from 3D images of each participant. Each participant was photographed twice, first without fiducial points marked (referred to as unmarked image) and second with fiducial points marked prior to imaging (referred to as marked image). Stereophotogrammetry was compared to traditional direct anthropometry, in which measurements were taken with a tape measure on participants. Three statistical analyses were used to evaluate the agreement between stereophotogrammetry and direct anthropometry. Seven out of nine distances showed excellent agreement between stereophotogrammetry and direct anthropometry (both marked and unmarked images). In addition, stereophotogrammetry from the unmarked image was equivalent to that of the marked image (both line-of-sight and contoured distances). A lower level of agreement was observed for some measures because of difficulty in localizing more vaguely defined fiducial points, such as lowest visible point of breast mound, and inability of the imaging system in capturing areas obscured by the breast, such as the inframammary fold. Stereophotogrammetry from 3D images obtained from the 3dMD torso system is effective for quantifying breast morphology. Tools for surgical planning and evaluation based on stereophotogrammetry have the potential to improve breast surgery outcomes.

Automated spatial alignment of 3D torso images

This paper describes an algorithm for automated spatial alignment of three-dimensional (3D) surface images in order to achieve a pre-defined orientation. Surface images of the torso are acquired from breast cancer patients undergoing reconstructive surgery to facilitate objective evaluation of breast morphology pre-operatively (for treatment planning) and/or post-operatively (for outcome assessment). Based on the viewing angle of the multiple cameras used for stereophotography, the orientation of the acquired torso in the images may vary from the normal upright position. Consequently, when translating this data into a standard 3D framework for visualization and analysis, the co-ordinate geometry differs from the upright position making robust and standardized comparison of images impractical. Moreover, manual manipulation and navigation of images to the desired upright position is subject to user bias. Automating the process of alignment and orientation removes operator bias and permits robust and repeatable adjustment of surface images to a pre-defined or desired spatial geometry.

Photometric calibration for quantitative spectral microscopy under transmitted illumination

Over the past decade, there have been significant developments in the mechanisms for examination of biological and material samples. These developments exploit techniques in light microscopy to elucidate specific parts of cells and tissues, as well as inorganic particles. In recent years, spectral microscopy has become more prevalent for characterization of samples. Simultaneously, sensor technology has progressed as well and modern charge-coupled devices (CCD) cameras are now capable of achieving high spatial resolution and high sensitivity measurements of signals in the optical microscope. One major impediment in obtaining absolute quantitative information of imaged samples is the lack of automated photometric calibration mechanisms for spectral microscopes. In this paper, we present a methodology for achieving photometric calibration of an automated spectral imaging system targeted towards examination of biological samples. By acquiring spatial and spectral data simultaneously, spectral imaging allows one to exploit physical connections between a particle's morphology and its characteristic response to the optical spectrum. In composite biological material, the interpretation of the spectra is a complicated problem. This is because any light source and charge-coupled device camera used for data acquisition does not have a uniform illumination spectra and quantum efficiency, respectively, across the emitted light spectra. To balance the spectral response across individual wavelengths, our method modulates the exposure duration for the charge-coupled device camera during image acquisition. We present an image similarity based method to calibrate the system. Experiments to test the effectiveness of the calibration method under the various image similarity metrics are presented along with results to show the calibrated system's ability to accurately measure spectra based on the measured transmission profiles of optical filters.

Strategies for automated fetal cell screening

Studies to date have demonstrated fetal sex determination and aneuploidy detection from maternal blood, but a clinical screening technique has not yet emerged. A key limiting factor is the small number of fetal cells, which makes detection specificity and reliability critical. Visual inspection of unsorted or sorted fetal cells is laborious, and cells can be easily missed. Moreover, it is impractical to examine manually all the separated cells. It is highly likely that automation may increase the number of cells inspected, resulting in higher detection sensitivities. Flow and image cytometry are two feasible approaches for automated detection of cells. This review details computerized microscopy (image cytometry) techniques for the automatic detection of fetal cells. Microscopy-based approaches used to identify fetal origin include: (i) immunocytochemical identification of fetal haemoglobin-specific cells (light or fluorescence microscopy); (ii) identification of sex chromosomes and/or aneuploidy using fluorescence in-situ hybridization; and (iii) morphological identification of nucleated red blood cells using light microscopy. The relevant instrumentation, including motorized stages and filters, cameras and digitizer boards are discussed, and software algorithms, including image enhancement, autofocusing, object detection and relocation, and features for operator review and data analysis, are outlined.

Network thermodynamic model of coupled transport in a multicellular tissue--the islet of Langerhans

Network thermodynamic modeling via bond graphs was used to describe the water and cryoprotectant additive (CPA) transport in a multicellular tissue. The model is presented as a tool to understand the osmotic behavior of the islets of Langerhans when exposed to ternary aqueous solutions containing an electrolyte and a CPA. It accounts for the effects of the location of cells within the tissue and an interstitial matrix, plus differential permeabilities to water and CPA. The interstitial matrix was assumed to be a porous medium able to store the chemical species being transported. Controlled osmotic stress experiments were conducted on isolated rat pancreas islets to measure the transient volumetric response to step-wise changes in dimethyl sulfoxide, Me2SO, concentration. The model provides a tool for predicting the transient volumetric response of peripheral and interior cells and of interstitial tissue, as well as the build up of solute concentration, during addition and removal of CPAs and freezing and thawing protocols. Inverse solution methods were applied to determine values for standard cell membrane permeability parameters Lp, omega and sigma as well as for the interstitial flow conductivities Kw and Kp'.

Poloxamer 188 enhances functional recovery of lethally heat-shocked fibroblasts

Damage to the cell membrane has been implicated as the primary event in the pathogenesis of heat shock, generally resulting in loss of cellular homeostasis and cell death. Thus a promising mode of therapy would involve the restoration of cell membrane integrity. Surfactant molecules, specifically triblock polymers such as Poloxamer 188 (P-188), possess the ability to self-aggregate into membrane-like structures in aqueous solutions and have been shown to restore membrane integrity. The objective of this study was to develop functional and morphological assays to determine whether treatment with P-188 after heat shock enhances the recovery of thermally damaged cells. Human foreskin fibroblasts were placed in sterile vials and heated by immersion in a calibrated water bath for various lengths of time at predefined temperatures. Cell recovery after heat shock was assessed using a functional assay based on the ability of the cells to contract fibroblast populated collagen lattices (FPCLs). Subsequent to heating, collagen lattices were prepared with control (no heat, no P-188) and heat shocked cells (with and without P-188). Our results indicate that treatment with low concentrations of P-188 after heat shock was effective in ameliorating both the morphological integrity and the contractile function of thermally damaged cells. Further, we observed that P-188 was most effective in improving the contractile ability of cells heat shocked at 45 degrees C; however, it had no influence on the contractility of cells exposed to higher temperatures. Our results suggest that there exists a threshold of thermal stress (45 degrees C for 20-60 min) beyond which treatment with low concentrations of P-188 (0.5 mg/ml) is ineffective in minimizing cell damage. Moreover, the results of our morphological assays indicate that cells treated with P-188 after heat shock maintain their cytoskeletal organization, whereas untreated cells exhibit filamentous actin depolymerization.

Angiogenesis in cultured and cryopreserved pancreatic islet grafts

BACKGROUND

The ability of rat pancreatic islets to revascularize after transplantation was examined via in vitro and in vivo imaging of the microvasculature using laser scanning confocal microscopy (LSCM).

METHODS

Cultured or cryoprocessed islets were transplanted at the renal subcapsular site in rats. At various time intervals after transplantation, three-dimensional imaging of the graft was performed by LSCM. In vitro studies were conducted via microvascular corrosion casting of the grafted kidney in situations where it was difficult to obtain in vivo confocal data due to surgical complications. The vascular morphology of the islet grafts was evaluated quantitatively via digital image analysis algorithms to determine the morphology of the neovascular ingrowth and the rate of revascularization.

RESULTS

In cultured islet grafts, the initiation of angiogenesis was observed within 1 week, characterized by the presence of capillary sprouts, tortuous vessels, and blood vessels with blind ends. The revascularization of the graft was typically completed within 2 weeks and could be distinguished as a network of completely perfused blood vessels consisting of intertwining capillaries, with surrounding arterioles and venules. The angiogenesis process in cryopreserved islet grafts required a longer time period to initiate (approximately 2 weeks), and the revascularization was completed in 1 week after the initiation.

CONCLUSIONS

These results successfully demonstrate the potential of the described in vivo and in vitro LSCM techniques to measure the angiogenesis process in pancreatic islet grafts.

Viability analysis of cryopreserved rat pancreatic islets using laser scanning confocal microscopy

We have developed a digital image analysis technique to assay the viability of frozen-thawed pancreatic islets by using laser scanning confocal microscopy (LSCM) in conjunction with double fluorescent staining [acridine orange/propidium iodide (AO/PI)]. Freshly isolated rat pancreatic islets were cultured for 18-24 h and then brought to a 2 M concentration of dimethyl sulfoxide (Me2SO) by serial addition at decreasing temperatures. Ice was nucleated in the islet suspension at a defined temperature (-10 degrees C), followed by a controlled period for equilibration and then cooling in a programmable bulk freezer at rates of 0.3, 1, 3, 10 and 30 degrees C/min to -70 degrees C. Samples were then stored in liquid nitrogen. Subsequent to rapid thawing and serial dilution with sucrose solution to remove Me2SO, AO/PI-stained individual islets were prepared for imaging on the LSCM. A series of optical sections through individual stained islets were obtained and processed to obtain high-contrast images at two different wavelengths; 488 nm and 514 nm for viable and damaged tissue, respectively. Image analysis algorithms consisted of template masking, generation of histograms of the pixel intensity profile, and gray level thresholding to obtain binary images. The total percentages of both types of tissue in the islet were computed by summing the two populations in each serial section. The spatial distributions of viable and damaged tissue were calculated from the three-dimensional (3-D) data base for both cultured (control) and cryopreserved islets. The 3-D spatial distributions of damaged and viable tissue in the islets were computed by determining the normalized distance of each viable/damaged voxel from the centroid of the islet volume to a mathematically estimated 3-D superquadric surface used to estimate the outer boundary of the islet. Further, each isolated damaged cell was identified and its volume determined. These studies indicate that cryopreserved islets exhibit shape distortion and a decrease in the numerical density of cells in comparison to unfrozen controls. Maximal survival was observed at the slower cooling rates. Accordingly, damage was found to occur throughout the 3-D islet volume in distinct spatial distributions for islets frozen at the slower and the faster cooling rates. Further, it was found that the volume of the majority of damaged cells identified was consistent with that of cells ranging in diameter from 5 to 9 micrometers.

In-vivo analysis of angiogenesis and revascularization of transplanted pancreatic islets using confocal microscopy

A technique to measure angiogenesis and revascularization in pancreatic islets transplanted at the renal subcapsular site in the rat has been developed. In-vivo imaging of the microcirculation of transplanted pancreatic islets was conducted using a confocal scanning laser microscope (CSLM) to achieve optical sectioning through the graft in order to perform a computer reconstruction of the three-dimensional neovascular morphology. Individual islets were harvested by enzymatic digestion of excised pancreas from Fischer 344 rats. Isolated islets were cultured for 24 h, and approximately 300-350 islets were transplanted at the renal subcapsular site of the left kidney in an anaesthetized rat. Six to 14 days post-transplantation, the animal was anaesthetized and prepared for in-vivo imaging of the microvasculature on a Zeiss LSM-10. Optical contrast of the microvasculature was enhanced by the administration of fluorescein-labelled dextran into the circulating blood. The transplant site was identified and serial sections were obtained through the vascular bed at varying z-intervals. Complementary fluorescence video images were also obtained via a silicon intensifier tube camera mounted on the CSLM. At completion of the imaging procedure, the kidney was returned into the body cavity, the area was sutured and the animal was allowed to recuperate for subsequent examinations. Image processing algorithms, such as grey-level thresholding, median filtering, skeletonization and template matching, were applied to compute the vessel density and diameters and extrapolated to measure 3-D vessel lengths and the tortousity index of the neovasculature.

Three-dimensional distribution of damaged cells in cryopreserved pancreatic islets as determined by laser scanning confocal microscopy

The technique of serial optical sectioning by confocal microscopy, in conjunction with off-line digital image analysis, was used to quantify the radial distribution of damaged cells in rat pancreatic islets following cryopreservation. The process consists of imaging frozen-thawed islets of Langerhans using laser scanning confocal microscopy (LSCM). The three-dimensional (3-D) distribution and analysis of the two populations of viable and damaged cells was visualized via acridine orange/propidium iodide (AO/PI) fluorescent staining. In preparation for cryopreservation, isolated and cultured rat pancreatic islets were brought to a 2 M concentration of dimethyl sulphoxide (DMSO) by serial addition at decreasing temperatures. Ice was nucleated in the islet suspension at -10 degrees C, and individual specimens were frozen to -70 degrees C at cooling rates of 1, 3, 10 and 30 degrees C/min in a programmable bulk freezer and subsequently stored in liquid nitrogen. After rapid thawing and serial dilution to remove DMSO, individual islets were prepared with AO/PI stains for imaging on the LSCM. Serial sections of the islets, 2-7 microns in thickness, were obtained and processed to obtain high-contrast images. Analysis algorithms consisted of template masking, grey-level thresholding, median filtering and 3-D blob colouring. The radial distribution of damaged cells in the islets was determined by isolating the cell and computing its distance from the centroid of the 3-D islet volume. An increase in the number of blobs corresponding to single and/or aggregates of damaged cells was observed progressively with distance from the centre towards the periphery of the islet. This pattern of freeze-induced killing of cells within the islet was found to occur consistently in the numerous individual specimens processed.