17β-estradiol promotes extracellular vesicle release and selective miRNA loading in ERα-positive breast cancer

The causes and consequences of abnormal biogenesis of extracellular vesicles (EVs) are not yet well understood in malignancies, including in breast cancers (BCs). Given the hormonal signaling dependence of estrogen receptor-positive (ER+) BC, we hypothesized that 17β-estradiol (estrogen) might influence EV production and microRNA (miRNA) loading. We report that physiological doses of 17β-estradiol promote EV secretion specifically from ER+ BC cells via inhibition of miR-149-5p, hindering its regulatory activity on SP1, a transcription factor that regulates the EV biogenesis factor nSMase2. Additionally, miR-149-5p downregulation promotes hnRNPA1 expression, responsible for the loading of let-7's miRNAs into EVs. In multiple patient cohorts, we observed increased levels of let-7a-5p and let-7d-5p in EVs derived from the blood of premenopausal ER+ BC patients, and elevated EV levels in patients with high BMI, both conditions associated with higher levels of 17β-estradiol. In brief, we identified a unique estrogen-driven mechanism by which ER+ BC cells eliminate tumor suppressor miRNAs in EVs, with effects on modulating tumor-associated macrophages in the microenvironment.

Abstract 1265: Identification of a predictive circulating immunological signature of response to immune checkpoint inhibitors in non-small cell lung cancer

In non-small cell lung cancer (NSCLC), response to immune checkpoint blockade (ICB) is associated with programmed cell death ligand 1 expression that is induced by interferon-γ-produced by tumor-infiltrating CD8+ T cells. However, not all tumors with a PD-L1 expression and/or CD8+ T cell infiltrate respond to ICB, and some tumors without any PD-L1 expression respond to ICB. Moreover, little is known about all the mechanisms governing ICB resistance in NSCLC. The objective of the study was to investigate a circulating immunological signature (cytokines, chemokines and immune checkpoints) which could be predictive of resistance to ICB in patients with advanced NSCLC. We performed a multiplexed analysis on 23 TruCulture® (in vitro T cells activation system) and 41 plasma samples using the Luminex® platform (Bio-Techne, MN USA). We investigated the relationship between the levels at baseline of 30 circulating analytes and the response to ICB of advanced NSCLC patients. Through the TruCulture® samples analysis, we identified two types of responders depending on T cell functionality. The responders with a functional T cell activation had lower levels of neutrophil associated analytes (CXCL5/6; p-value<0.05) than non-responders. They had lower levels of IL-13 and higher levers of TNFα, respectively Th2 and Th1/CD8+/NK associated analytes. All responders had lower levels of CCL17 and higher levels of CXCL10 in plasma samples, respectively M2/N2 and M1/N1 associated analytes. This study highlighted two distinct profiles of ICB responders. The first group has a functional T cell response with a favorable orientation to antitumor cytotoxic action (Th1/CD8+) and few cytokines associated with neutrophils. The second group has a poor functional T cell response, whereas their favorable response to ICB is potentially linked to the activation of the innate immune response. The plasma study highlighted the potential role of polarization of the innate response in the context of the response to ICB for all patients.

Citation Format: Wassila Khatir, Olivier Humbert, Jaap Neels, Léa Berland, Jonathan Benzaquen, Fabian Andrés Gallardo Rivera, Maryline Allegra, Myriam Salah, Virginie Tanga, Olivier Bordone, Julien Fayada, Virginie Lespinet-Fabre, Elodie Long-Mira, Sandra Lassalle, Patrick Brest, Valérie Vouret, Charlotte Maniel, Jacques Boutros, Simon Heeke, Véronique Hofman, Charles-Hugo Marquette, Paul Hofman, Marius Ilie. Identification of a predictive circulating immunological signature of response to immune checkpoint inhibitors in non-small cell lung cancer [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 1265.

Nanobodies for Medical Imaging: About Ready for Prime Time?

Recent advances in medical treatments have been revolutionary in shaping the management and treatment landscape of patients, notably cancer patients. Over the last decade, patients with diverse forms of locally advanced or metastatic cancer, such as melanoma, lung cancers, and many blood-borne malignancies, have seen their life expectancies increasing significantly. Notwithstanding these encouraging results, the present-day struggle with these treatments concerns patients who remain largely unresponsive, as well as those who experience severely toxic side effects. Gaining deeper insight into the cellular and molecular mechanisms underlying these variable responses will bring us closer to developing more effective therapeutics. To assess these mechanisms, non-invasive imaging techniques provide valuable whole-body information with precise targeting. An example of such is immuno-PET (Positron Emission Tomography), which employs radiolabeled antibodies to detect specific molecules of interest. Nanobodies, as the smallest derived antibody fragments, boast ideal characteristics for this purpose and have thus been used extensively in preclinical models and, more recently, in clinical early-stage studies as well. Their merit stems from their high affinity and specificity towards a target, among other factors. Furthermore, their small size (~14 kDa) allows them to easily disperse through the bloodstream and reach tissues in a reliable and uniform manner. In this review, we will discuss the powerful imaging potential of nanobodies, primarily through the lens of imaging malignant tumors but also touching upon their capability to image a broader variety of nonmalignant diseases.

FuncPEP: A Database of Functional Peptides Encoded by Non-Coding RNAs

Non-coding RNAs (ncRNAs) are essential players in many cellular processes, from normal development to oncogenic transformation. Initially, ncRNAs were defined as transcripts that lacked an open reading frame (ORF). However, multiple lines of evidence suggest that certain ncRNAs encode small peptides of less than 100 amino acids. The sequences encoding these peptides are known as small open reading frames (smORFs), many initiating with the traditional AUG start codon but terminating with atypical stop codons, suggesting a different biogenesis. The ncRNA-encoded peptides (ncPEPs) are gradually becoming appreciated as a new class of functional molecules that contribute to diverse cellular processes, and are deregulated in different diseases contributing to pathogenesis. As multiple publications have identified unique ncPEPs, we appreciated the need for assembling a new web resource that could gather information about these functional ncPEPs. We developed FuncPEP, a new database of functional ncRNA encoded peptides, containing all experimentally validated and functionally characterized ncPEPs. Currently, FuncPEP includes a comprehensive annotation of 112 functional ncPEPs and specific details regarding the ncRNA transcripts that encode these peptides. We believe that FuncPEP will serve as a platform for further deciphering the biologic significance and medical use of ncPEPs.

Multiplexed Immunohistochemistry for Molecular and Immune Profiling in Lung Cancer-Just About Ready for Prime-Time?

As targeted molecular therapies and immuno-oncology have become pivotal in the management of patients with lung cancer, the essential requirement for high throughput analyses and clinical validation of biomarkers has become even more intense, with response rates maintained in the 20%–30% range. Moreover, the list of treatment alternatives, including combination therapies, is rapidly evolving. The molecular profiling and specific tumor-associated immune contexture may be predictive of response or resistance to these therapeutic strategies. Multiplexed immunohistochemistry is an effective and proficient approach to simultaneously identify specific proteins or molecular abnormalities, to determine the spatial distribution and activation state of immune cells, as well as the presence of immunoactive molecular expression. This method is highly advantageous for investigating immune evasion mechanisms and discovering potential biomarkers to assess mechanisms of action and to predict response to a given treatment. This review provides views on the current technological status and evidence for clinical applications of multiplexing and how it could be applied to optimize clinical management of patients with lung cancer.

Current views on tumor mutational burden in patients with non-small cell lung cancer treated by immune checkpoint inhibitors

In the last few years, the treatment of patients with non-small cell lung cancer (NSCLC) has impressively benefitted from immunotherapy, in particular from the inhibition of immune checkpoints such as programmed cell death-1 (PD-1) and programmed cell death ligand-1 (PD-L1). However, despite the significant survival benefit for some patients with advanced NSCLC, the objective response rates (ORRs) remain relatively low no more than 20-30% with a large proportion of patients demonstrating primary resistance. Although the selection of NSCLC patients for the first-line treatment is currently guided by the expression of PD-L1 in tumor cells as detected by immunohistochemistry, this is not the case for the second-line setting. Moreover, the sensitivity and specificity of PD-L1 expression is modest which has prompted the search for additional predictive biomarkers. In this context, the assessment of the tumor mutational burden (TMB), defined as the total number of nonsynonymous mutations in the coding regions of genes, has recently emerged as an additional powerful biomarker to select patients for immunotherapy. The purpose of our review is to highlight the recent advances as well as the challenges and perspectives in the field of TMB and immunotherapy for patients with NSCLC.

Development and Validation of Computed Tomography Derived Anthropometric Regression Equations for Estimating Abdominal Adipose Tissue Distribution

The purpose of this study was twofold: (1) to develop multiple regression equations for predicting computed tomography (CT) derived intra-abdominal (IAF), subcutaneous (SCF), and total (TOTF= IAF+SCF) abdominal adipose tissue areas from anthropometric measures in adult white males with a large range of age (18-71 years) and percent body fat (2.0-40.6); and (2) to validate the new and existing equations that used similar Hounsfield Units (HU) for determining IAF for estimating these fat depots. One hundred fifty-one white male subjects had IAF, SCF, and TOTF determined by a single CT scan, skinfold and circumference measures taken and body density determined. Linear intra-correlations and factor analysis procedures were used to identify variables for inclusion in stepwise multiple regression solutions. IAF was estimated from age, waist circumference, the sum of mid-thigh and lower thigh circumferences, and vertical abdominal skinfold. SCF was estimated from age, umbilicus circumference, chest and suprailiac skinfolds. TOTF was estimated from age, body mass index (BMI), chest skinfold, and umbilicus circumference. R2 for IAF, SCF, and TOTF was .73, .77, and .86 respectively. The existing and the new equations were validated on an independent sub-sample of 51 subjects. The only existing equation that met validation criteria had a validation R2 = .67 for IAF. All three new equations met validation criteria with R2 validations of .75, .79, and .85 for IAF, SCF, and TOTF respectively. It is concluded that the new equations might be used as an inexpensive estimation of IAF, SCF, and TOTF in adult white males varying greatly in age and percent body fat.

Intra-abdominal adipose tissue values associated with risk of possessing elevated blood lipids and blood pressure

Central fat distribution and more recently intra-abdominal adipose tissue (IAF) have been associated with elevated cardiovascular risk factors (CRF). Despite increased interest in use of LAF for screening for CRF, interpretation of risk found in a specific IAF is difficult since regressions for estimating CRF from IAF have not been published. The purpose of this paper is to report IAF values that are likely to be associated with elevated CRF. One hundred forty-six healthy male subjects 30-71 years were evaluated for IAF and subcutaneous fat (computed tomography scan at 4th lumbar vertebra), height, body weight, % fat, various anthropometric measures, blood cholesterol (CHOL), HDL cholesterol (HDL), systolic blood pressure (SBP), and diastolic blood pressure (DBP). Receiver-Operating-Characteristic curves (ROC) were used to develop IAF cutpoints associated with elevation of at least one established CRF criteria (CHOL=200, HDL=<35, SBP=140, DBP=90). A sensitivity/(1- specificity) curve established the value of using IAF cutpoints for detecting elevated CRF. Likelihood ratios were used to identify optimal cutpoints. Two cutpoints were identified, 131 cm2 with a relatively high Lpos ratio and 71 cm2 with a relatively low Lneg. False positives associated with 131 cm2 were 14% for one or more elevated CRF. False negatives associated with 71 cm2 were 9% for one or more elevated CRF, 4% for two or more CRF, and 0% for three or more elevated CRF. This study clearly indicates that IAF above 131 cm2 is related to elevated CRF and IAF below 71 cm2 is associated with reduced cardiovascular risk.

Variability of abdominal adipose tissue measurements using computed tomography in prepubertal girls

OBJECTIVE

To determine the variability of measuring regional adipose tissue area using abdominal computed tomography (CT) in normal-weight, prepubertal girls.

DESIGN

Measurements of abdominal CT were performed twice, 6 weeks apart.

SUBJECTS

Sixty-one normal-weight, prepubertal girls (age: 4.8-10.3 y, mean (s.d.) BMI: 16.7 +/- 1.5 kg/m2).

MEASUREMENTS

Abdominal adipose tissue by CT at baseline and 6 weeks later.

RESULTS

There were no significant differences between visits 1 and 2 with regard to the children's average abdominal CT derived intraabdominal adipose tissue (21.64 cm2 vs 23.74 cm2) and subcutaneous adipose tissue (62.49 cm2 vs 65.28 cm2). The Pearson coefficient of correlation (r), P-value, total coefficient of variation (CV) and standard error of the difference (SEdelta) for intra-individual measurements between visits 1 and 2 by abdominal CT were: total abdominal adipose tissue, r = 0.94, P < 0.0001, CV = 12.34%, SEdelta 2.25 cm2; subcutaneous abdominal adipose tissue, r = 0.96, P < 0.0001, CV = 10.67%, SEdelta = 1.57 cm2; and intraabdominal adipose tissue, r = 0.67, P < 0.0001, CV = 21.5%, SEdelta = 1.11 cm2. The mean ratios of intraabdominal to subcutaneous adipose tissue on visits 1 and 2 were 0.42 +/- 0.2 and 0.44 +/- 0.24, respectively.

CONCLUSION

Regional adipose tissue area measurements using abdominal CT were reliable in healthy, normal-weight, prepubertal girls.

Fat distribution, physical activity, and cardiovascular risk factors

The purpose of this study was to report the relationship between fat distribution, physical activity (PA), and cardiovascular disease (CVD) risk factors. Percent fat, computed tomography intra-abdominal adipose tissue (IAF), anthropometrics, Baecke activity questionnaire, and CVD risk (blood pressure, cholesterol, HDL, HDL2, HDL3, IDL, LDL, VLDL, and triglycerides) were evaluated in 137 men 30-71 yr old. IAF was consistently more highly related to CVD risk than other fat distribution variables including percent fat and waist:hip ratio (r = 0.3-0.45). IAF was significantly related to CVD risk after adjusting for other fat distribution variables. With the exception of the sum of biceps, triceps, thigh, and calf skinfolds (peripheral skinfolds), which was negatively related to CVD risk, no other fat distribution variable had consistent significant partial correlations with CVD risk. PA was related to IAF after adjusting for peripheral skinfolds, but PA was not related to peripheral skinfolds after adjusting for IAF, indicating more active men have relatively low IAF. IAF was related to CVD risk after adjusting for PA, but PA was not related to CVD risk after adjusting for IAF. These results indicate that IAF is directly related to CVD risk while the lower CVD risk found with more active men is more directly related to the low IAF found in more active men.

Intra-abdominal adipose tissue cut-points related to elevated cardiovascular risk in women

Intra-abdominal adipose tissue (IAF) seems to be the primary fat depot putting individuals at risk for cardiovascular disease (CVD). The purpose of this study was to determine IAF cut-points for identifying CVD risk in pre- and post-menopausal women. Age ranged from 18 to 77 y and percentage fat ranged from 9 to 48%. Computed tomography (CT), IAF, DEXA determined regional fat and blood lipid profiles were obtained on 220 Caucasian women. Student's t-tests were run to determine differences between pre- and post-menopausal women. Receiver-operating characteristic (ROC) analysis was used to develop IAF cut-points associated with elevated CVD risk. Post-menopausal women had higher percentage fat, greater proportion IAF and higher CVD risk. Menopausal status was not consistently independently related to CVD risk after adjusting for IAF, but IAF was after adjusting for menopausal status. The same cut-points for CVD risk were found with both 4- and 6-CVD risk factor analysis and for both pre- and post-menopausal as well as pooled data. 4-CVD risk factor analysis comprised cholesterol (C), HDL-C, systolic blood pressure and diastolic blood pressure. 6-CVD risk factor analysis comprised the 4-CVD risk factors plus triglycerides and cholesterol : HDL-C ratio. ROC L positive values indicate levels of IAF above which metabolic disturbances will be increased and were determined to be 110 cm2. ROC L negative values indicate levels of IAF below which CVD risk will not be affected and were determined to be 40 cm2. False positives were 3% and false negatives were 9%. ANOVA comparing women with IAF cross-sections less than 40 cm2, between 40 and 110 cm2 and more than 110 cm2 demonstrate large differences in CVD risk profile. It is suggested women who have IAF values above 110 cm2 are in jeopardy of possessing elevated CVD risk.

Reduction in intra-abdominal adipose tissue after strength training in older women

The purpose of this study was to examine the effects of a total body strength-training program on changes in total and regional body composition, in particular intra-abdominal adipose tissue (IAAT), in older women. Fourteen healthy older women (mean age 67 +/- 1 yr) exercised 3 times/wk for 16 wk. Strength was assessed by one-repetition maximum tests, with training intensity gradually increased to approximately 67% of one repetition maximum. Body composition was measured by hydrodensitometry and regional body composition was measured by computed tomography. Strength was significantly increased in the upper (51%) and lower body (65%). There was no significant change in body weight (64.4 +/- 2.7 vs. 64.2 +/- 2.7 kg), total body fat (38.7 +/- 1.4 vs. 38.0 +/- 1.6%) or fat-free mass (39.7 +/- 1.0 vs. 40.0 +/- 0.9 kg). However, after ST, there were significant reductions in IAAT (143.9 +/- 13.3 vs. 130.0 +/- 12.4 cm2), the IAAT-to-subcutaneous adipose tissue ratio (0.48 +/- 0.04 vs. 0.44 +/- 0.04), and midthigh subcutaneous adipose tissue (141.7 +/- 11.5 vs. 133.6 +/- 10.8 cm2) and an increase in midthigh muscle (52.9 +/- 2.6 vs. 58.0 +/- 2.0 cm2) (all P < 0.05). In conclusion, significant reductions in IAAT and an increase in strength and muscle area were observed after a strength-training program in healthy older women. These changes may be important in preventing the negative health outcomes associated with the age-related increase in intra-abdominal obesity.

Clinically guided closure of femoral arterial pseudoaneurysms complicating cardiac catheterization and coronary angioplasty

Femoral artery pseudoaneurysm formation is a significant problem in patients undergoing cardiac catheterization and interventional cardiac procedures. It is especially more common with the use of anticoagulant and antiplatelet therapy and the use of intracoronary stents. We describe our initial experience with clinically guided bedside compression of femoral pseudoaneurysms in such patients. Eleven patients, 10 undergoing coronary angioplasty (including 3 with intracoronary stents) and 1 undergoing diagnostic cardiac catheterization, developed a femoral pseudoaneurysm. All patients had a femoral bruit and 9 had an expansile groin hematoma. The diagnosis was confirmed in each case by Doppler ultrasound. Seven patients were receiving heparin while 4 were on oral anticoagulants at the time of detection of the pseudoaneurysm. These patients underwent clinically guided graded external compression to close the pseudoaneurysm neck while maintaining femoral arterial flow. External compression for 104.1 +/- 63 min resulted in successful clinical resolution of pseudoaneurysm in all patients without complications. The results were confirmed by Doppler ultrasound at least 12 hr later. Bedside compression of femoral pseudoaneurysms guided by clinical clues is simple and appears to be an effective and safe technique to manage this iatrogenic problem.

Planning interactive implant treatment with 3-D computed tomography

Treatment planning for dental implants presents special challenges to the dentist. The authors review the conventional radiographic and non-radiographic methods for the assessment of the implant site. A new dental interactive treatment planning program under development at the University of Alabama School of Dentistry Department of Periodontics is described.