Somatic Mutations in Latin American Breast Cancer Patients: A Systematic Review and Meta-Analysis

(1) Background: Somatic mutations may be connected to the exposome, potentially playing a role in breast cancer's development and clinical outcomes. There needs to be information regarding Latin American women specifically, as they are underrepresented in clinical trials and have limited access to somatic analysis in their countries. This study aims to systematically investigate somatic mutations in breast cancer patients from Latin America to gain a better understanding of tumor biology in the region. (2) Methods: We realize a systematic review of studies on breast cancer in 21 Latin American countries using various databases such as PubMed, Google Scholar, Web of Science, RedAlyc, Dianlet, and Biblioteca Virtual en Salud. Of 392 articles that fit the criteria, 10 studies have clinical data which can be used to create a database containing clinical and genetic information. We compared mutation frequencies across different breast cancer subtypes using statistical analyses and meta-analyses of proportions. Furthermore, we identified overexpressed biological processes and canonical pathways through functional enrichment analysis. (3) Results: 342 mutations were found in six Latin American countries, with the TP53 and PIK3CA genes being the most studied mutations. The most common PIK3CA mutation was H1047R. Functional analysis provided insights into tumor biology and potential therapies. (4) Conclusion: evaluating specific somatic mutations in the Latin American population is crucial for understanding tumor biology and determining appropriate treatment options. Combining targeted therapies may improve clinical outcomes in breast cancer. Moreover, implementing healthy lifestyle strategies in Latin America could enhance therapy effectiveness and clinical outcomes.

Rhinitis associated with asthma is distinct from rhinitis alone: The ARIA-MeDALL hypothesis

Asthma, rhinitis and atopic dermatitis (AD) are interrelated clinical phenotypes that partly overlap in the human interactome. The concept of "one-airway-one-disease", coined over 20 years ago, is a simplistic approach of the links between upper- and lower-airway allergic diseases. With new data, it is time to reassess the concept. This article reviews (i) the clinical observations that led to Allergic Rhinitis and its Impact on Asthma (ARIA), (ii) new insights into polysensitisation and multimorbidity, (iii) advances in mHealth for novel phenotype definition, (iv) confirmation in canonical epidemiologic studies, (v) genomic findings, (vi) treatment approaches and (vii) novel concepts on the onset of rhinitis and multimorbidity. One recent concept, bringing together upper- and lower-airway allergic diseases with skin, gut and neuropsychiatric multimorbidities, is the "Epithelial Barrier Hypothesis". This review determined that the "one-airway-one-disease" concept does not always hold true and that several phenotypes of disease can be defined. These phenotypes include an extreme "allergic" (asthma) phenotype combining asthma, rhinitis and conjunctivitis. Rhinitis alone and rhinitis and asthma multimorbidity represent two distinct diseases with the following differences: (i) genomic and transcriptomic background (Toll-Like Receptors and IL-17 for rhinitis alone as a local disease; IL-33 and IL-5 for allergic and non-allergic multimorbidity as a systemic disease), (ii) allergen sensitisation patterns (mono- or pauci-sensitisation versus polysensitisation), (iii) severity of symptoms and (iv) treatment response. In conclusion, rhinitis alone (local disease) and rhinitis with asthma multimorbidity (systemic disease) should be considered as two distinct diseases, possibly modulated by the microbiome, and may be a model for understanding the epidemics of chronic and auto-immune diseases.

Spectrum of germline mutations among Mexican patients with colorectal cancer

78

Background: Colorectal cancer (CRC) is the third most common cancer in the world, and the second most frequent cause of death due to cancer. 5-10% of CRC cases are due to a hereditary predisposing syndrome, the most frequent being Lynch Syndrome (LS) followed by Familial Adenomatous Polyposis (FAP), characterized by loss of function of mismatch repair genes (MMR) and APC, respectively. The purpose of this study is to describe the spectrum of germline pathogenic variants among Mexican CRC patients using Next-generation sequencing (NGS). Methods: This study is original research approved by IRB; all patients signed the informed consent. 43 patients between 18-60 y/o with CRC were enrolled. NGS was performed using a panel which targeted a set of 94 genes and 284 SNPs known to play a role in cancer predisposing. Bioinformatics data analysis was carried out using Pediatric Cancer Variant Pathogenicity Information Exchange (PeCanPIE) and an in-silico analysis to classify variants according to the American College of Medical Genetics and Genomics (ACMG) guidelines. Results: Mean age 48.71 y/o, 62.6% men. Germline pathogenic and likely pathogenic variants (PV/LP) were identified in 69% of sample. A molecular diagnosis of LS (MLH1, MSH2, MSH6, and PMS2) was confirmed in 12 (28%), and FAP in 5 (11.6%). It is remarkably the presence of 5 PV in PRF1 (2 G149S; 3 A91V), among other unusual genes for CRC. Also 12 double heterozygotes were identified, including one with PRF1 and CHEK2 PV. Conclusions: NGS allow the discover of new pathogenic variants that would not be suspected in classic hereditary syndromes. The understanding of other genes involved in other pathways could expand our understanding in the heritability of CRC. PRF1 emerges as a new candidate gene associated with CRC, previous evidence supports the role of PRF1 in solid tumors beside hematologic malignancies.

Abstract P039: Framework for genomic cancer risk assessment dissemination and implementation in Latin America: The GRACIAS (genetic risk assessment for cancer implementation and sustainment) study

Introduction: Lack of public insurance coverage for genetic testing and a limited trained genomic cancer risk assessment (GCRA) workforce are barriers to cancer screening and prevention and to understanding the genetic epidemiology of cancer in low/middle income countries (LMIC) in Latin America. Methods: We implemented an intervention that included professional education for clinicians in Mexico, Peru and Colombia, support from a community of practice and a federated consortium of collaborators, a versatile research registry with a dual purpose (research and clinical care) centralized relational database and pedigree drawing program (web-accessible), and economical NGS multigene panel tests (MGPT). We report here the outcomes of GCRA for 4181 probands (3170 breast, 301 ovarian, 965 other cancer, and 262 unaffected). Results: With a mean age of 45.2 y.o. (39.9 y.o. at breast cancer dx for carriers), a pathogenic variant (PV) was detected in 605 (14.5%) of 2,710 probands (BRCA testing only for 1387, MGPT for 1323): BRCA1 (n=250); BRCA2 (129); CHEK2 (24); PALB2 (20); ATM (14); TP53 (14); PTEN (6); CDH1 (5); MMR genes (62); RAD51C (6); and BRIP1 (3). We have documented growing reach (proportion of those eligible that access GCRA), increasing cascade testing (family member(s) tested (n=541) for 192/470 [40%] probands with a PV), and with median 2.2 years follow up, 209 risk reduction surgeries were performed. Summary: Remarkably, despite systemic limitations, integration of a skilled multidisciplinary team with access to genetic assays and practice support tools, community, and hospital outreach increased GCRA reach, and the expansion of cascade testing and performance of risk-appropriate surgeries reflect maturing prevention programs. Sustainment of progress requires increased multilevel efforts and establishment of GCRA as a supported standard of care, so the opportunity for prevention is not missed for vulnerable and underserved high-risk patients and families.

Citation Format: Jeffrey N. Weitzel, Julio Abugattas, Cynthia Villarreal-Garza, Adrian Daneri Navarro, Alicia Cock-Rada, Yenni Rodriguez, Pamela Mora-Alferez, Dione Aguilar, Azucena del Toro-Valero, Francisco Gutierrez-Delgado, Ana Ferrigno, Josef Herzog, Danielle Castillo, Gubidxa Gutierrez Seymour, Bita Nehoray, Kathleen R. Blazer, Maria E. Fernandez, Yanin Chavarri Guerra. Framework for genomic cancer risk assessment dissemination and implementation in Latin America: The GRACIAS (genetic risk assessment for cancer implementation and sustainment) study. [abstract]. In: Proceedings of the AACR Special Conference: Precision Prevention, Early Detection, and Interception of Cancer; 2022 Nov 17-19; Austin, TX. Philadelphia (PA): AACR; Can Prev Res 2023;16(1 Suppl): Abstract nr P039.

Germline pathogenic variants in Mexican patients with hereditary triple-negative breast cancer

Objective. Describe the prevalence of breast cancer (BC)- associated germline pathogenic variants (PVs) among Mexican patients with triple-negative BC (TNBC). Materials and methods. The spectrum of PVs identified among patients with TNBC who were enrolled in a prospective registry and underwent genetic testing was analyzed. Results. Of 387 patients with invasive TNBC and a median age at diagnosis of 39 years (range 21-72), 113 (29%) were carriers of PVs in BC-susceptibility genes: BRCA1 (79%), BRCA2 (15%), and other (6%: ATM, BRIP1, PALB2, PTEN, RAD51C, and TP53). PV carriers were younger at BC diagnosis (37 vs. 40 years, p=0.004) than non-carriers. Conclusion. A large proportion of TNBC in Mexican patients is associated with germline PVs, the vast majority in BRCA. The incremental yield of PVs in other BC-susceptibility genes was modest, and a stepwise approach starting with BRCA testing may be justified if it is more cost-effective than multigene panel testing.

Development and Pilot Implementation of the Genomic Risk Assessment for Cancer Implementation and Sustainment (GRACIAS) Intervention in Mexico

PURPOSE

Genomic cancer risk assessment (GCRA) is standard-of-care practice that uses genomic tools to identify individuals with increased cancer risk, enabling screening for early detection and cancer prevention interventions. GCRA is not available in most of Mexico, where breast cancer (BC) is the leading cause of cancer death and ovarian cancer has a high mortality rate.

METHODS

Guided by an implementation science framework, we piloted the Genomic Risk Assessment for Cancer Implementation and Sustainment (GRACIAS) intervention, combining GCRA training, practice support, and low-cost BRCA1/2 (BRCA) gene testing at four centers in Mexico. The RE-AIM model was adapted to evaluate GRACIAS intervention outcomes, including reach, the proportion of new patients meeting adapted National Comprehensive Cancer Network criteria who participated in GCRA. Barriers to GCRA were identified through roundtable sessions and semistructured interviews.

RESULTS

Eleven clinicians were trained across four sites. Mean pre-post knowledge score increased from 60% to 67.2% (range 53%-86%). GCRA self-efficacy scores increased by 31% (95% CI, 6.47 to 55.54; P = .02). Participant feedback recommended Spanish content to improve learning. GRACIAS promoted reach at all sites: 77% in Universidad de Guadalajara, 86% in Instituto Nacional de Cancerología, 90% in Tecnológico de Monterrey, and 77% in Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán. Overall, a pathogenic BRCA variant was identified in 15.6% (195 of 1,253) of patients. All trainees continue to provide GCRA and address barriers to care.

CONCLUSION

We describe the first project to use implementation science methods to develop and deliver an innovative multicomponent implementation intervention, combining low-cost BRCA testing, comprehensive GCRA training, and practice support in Mexico. Scale-up of the GRACIAS intervention will promote risk-appropriate care, cancer prevention, and reduction in related mortality.

Measuring TB drug levels in the hair in adults and children to monitor drug exposure and outcomes

INTRODUCTION: Testing for anti-TB drugs in small hair samples may serve as a non-invasive tool to measure cumulative drug exposure and/or adherence, as these determine treatment success. We aimed to assess how well hair assays of TB drugs predict TB treatment outcomes.METHODS: A small thatch of hair, ~30 strands, was cut from the occipital region in adults and children from a prospective TB cohort in India. Isoniazid (INH), acetyl-INH and pyrazinamide (PZA) were extracted from the hair samples and quantified using liquid-chromatography-tandem mass spectrometry. The relationship between drug concentrations in hair and time to unfavourable outcomes was assessed using Cox-proportional hazards regression models.RESULTS: A two-fold increase in hair acetyl-INH concentrations in the 264 participants in our cohort with hair assays for TB drugs indicated a lower hazard of unfavourable TB treatment outcomes (aHR 0.67, 95%CI 0.44-1.02) and TB treatment failure (aHR 0.65, 95%CI 0.42-1.01). Higher summed concentrations (a summed measure of INH and acetyl-INH) indicated a lower hazard of treatment failure (aHR 0.69, 95%CI 0.45-1.05)CONCLUSION: Hair levels of INH and its metabolite may predict TB treatment outcomes, indicating the potential utility of this measure to assess and optimise TB treatment outcomes.

Factors associated with breast self-examination in Mexican young women with breast cancer

10562

Background: Breast cancer (BC) is the most common cause of cancer-related death and morbidity among young women in Latin America. This group has a higher prevalence of advanced disease stages at diagnosis compared to their older counterparts. Thus, strategies aimed at detecting BC at early stages are imperative. Breast self-examination (BSE) remains a useful strategy for BC detection, especially in women who do not routinely undergo screening with imaging studies. This study aims to evaluate factors related with BSE practice in Mexican young women with BC and assess its association with earlier disease stages. Methods: Women aged ≤40 newly diagnosed with BC from 2014 to 2020 at three cancer referral centers in Mexico accrued in the Joven & Fuerte cohort were included and asked to complete a socio-demographic survey. Fisher’s exact and Mann-Whitney U tests were used to evaluate associations between BSE and socio-demographic characteristics, as well as disease stages. Results: A total of 554 patients with a median age at diagnosis of 36 years (range: 19-40) were analyzed. Most patients (65%) were married or in a domestic partnership, and the majority were housewives (63%). Regarding educational background, 64% had completed at least high school, and up to 84% had a monthly income < 11,600 Mexican pesos (US$ 581). Overall, 85% of patients had public insurance, 6% had private insurance, and 9% were uninsured. The distribution of clinical stages at diagnosis was: 0 (2%), I (11%), II (45%), III (32%), and IV (10%). BC detection methods were: 85% by self/partner exam, 11% by an imaging study, and 4% by a healthcare professional. A total of 443 (80%) patients practiced BSE, of which 50% did it on a monthly basis, 18% every 2-3 months, and the remaining 12% every 4-12 months. Notably, a higher educational level (≥ high school v ≤ middle school) was positively associated with BSE practice (RR: 1.28; 95%CI 1.06-1.54; p= 0.005). No significant association was found between BSE and age (≤35 v > 35), marital status (in a relationship v no), occupation (housewive v other), monthly income ( < 11,600 v ≥11,600) or medical coverage (public/uninsured v private). Patients that performed BSE were more likely to be diagnosed with early BC (stages 0-II) compared to those that did not (61% v 45%; p= 0.003). No association was found between BSE frequency and stage at diagnosis. Noteworthy, patients with private insurance were more likely to be diagnosed with stages 0-II compared to those with public or no insurance (80% v 56%; p= 0.007). Conclusions: The significant association between BSE and earlier stages at diagnosis found in this study highlights the need to raise awareness and promote this practice among young women with the objective of downstaging BC diagnoses. Public health interventions such as educational and social media campaigns that aim to improve the correct practice of BSE might be particularly useful in settings with inadequate screening programs.

High-early recurrence rate in a cohort of young women with breast cancer in Mexico

e12560

Background: Young women with breast cancer (YWBC) have worse survival outcomes compared to their older counterparts. Even though a higher recurrence rate has been previously documented in this population, there is still limited information regarding the timing, prevalence and type of disease recurrence. This study aims to describe the patterns of early recurrence in Mexican YWBC. Methods: Women aged ≤40 years at diagnosis, accrued in the Joven & Fuerte prospective cohort, with stage I-III BC and having at least a 2-year follow-up were analyzed. Recurrence-free survival (RFS) and overall survival (OS) at 2 years were evaluated using the Kaplan-Meier estimate. Log-rank and Fisher’s exact tests were employed for group comparisons; the Cox regression method was used to identify factors associated with RFS and OS. Results: A total of 210 patients with a median age at diagnosis of 36 years (range: 21-40) were analyzed. Most patients were diagnosed with stage II (50%) and III (39%). Distribution according to molecular subtype was: 50% HR+/HER2-, 26% TNBC, 17% HR+/HER2+, and 7% HR-/HER2+. In total, 31 (15%) patients experienced early disease recurrence. The two BC subtypes with the highest recurrence rate were TNBC (12/54; 22%) and HR+/HER2+ (6/35; 17%), followed by HR+/HER2- (12/106; 11%) and HR-/HER2+ (1/15; 7%). Stage at diagnosis was associated with a higher risk of recurrence (stage III: 21/82 (68%); stage II: 10/94 (32%); p= 0.003). Of the total recurrences, 23% were locorregional and the remaining 77% were distant metastases. The most common sites of distant metastases were lung (46%), bone (38%) and central nervous system (33%). Notably, 50% of distant recurrences affected multiple organs. Overall, RFS at 2 years was 85.2% (95%CI 79.7-89.4). In the univariate analysis, age ( < 35 v ≥35), type of surgery (conservative v mastectomy) and BMI ( < 25 v ≥25 kg/m²) were not significantly associated with RFS. In a multivariate model, node involvement (HR = 2.76; p= 0.044), not receiving chemotherapy (HR = 3.86; p= 0.024) and TNBC (HR = 2.47; p= 0.035) were independently associated with worse RFS. The OS found in this cohort was 92.9% (95%CI 88.4-95.6). In a multivariate model, TNBC (HR = 3.71; p= 0.029) and stage III at diagnosis (HR = 5.55; p= 0.008) were associated with worse OS. Conclusions: This cohort of YWBC experienced a low RFS at 2 years. As previously reported, patients with node involvement and TNBC faced a greater risk of early recurrence. Noteworthy, a high prevalence of distant metastases was observed, with half of them involving > 1 site. Future studies are warranted to elucidate the factors associated with early recurrence in YWBC. In addition, the incorporation of new treatment strategies is urgently needed to improve disease outcomes in this group.

Abstract PS8-25: Genetic cancer risk assessment and its impact on the uptake of cancer risk reduction strategies: The experience of a Mexican center

Background: The implementation of genetic cancer risk assessment (GCRA) in resource-constrained settings is limited due to multiple factors, including insufficient access to preventive strategies. In our center, GCRA was formally established in 2014, and access to genetic testing is provided to underserved patients through a research collaboration with City of Hope's CCGCRN. The aim of this study is to determine the proportion of patients with germline mutations that underwent risk-reducing surgeries (RRS) and followed recommended breast cancer (BC) screening strategies.

Methods: Patients that received GCRA in a center located in Monterrey, Mexico who met NCCN criteria for testing for BC predisposition genes were eligible. Information on mutation status, performance of RRS and BC screening strategies was prospectively collected. The patients were grouped by type of healthcare (i.e. private vs public), with differences explored using Fisher's exact or Mann Whitney U tests, as appropriate.

Results: Between 2014 and 2019, a total of 437 probands and 139 of their relatives underwent GCRA. Of these, 23% and 37% were identified as mutation carriers, respectively: BRCA1/2 (72.5%), PALB2 (6.4%), CHEK2 (6.4%) and others (14.7%). The median time elapsed from disclosure of genetic test results to collection of data was 16 months. The median age was 41 years, with no statistical difference according to type of healthcare. Based on NCCN guidelines, 151 RRS were recommended according to mutational status and age, of which 52 (34%) were performed: 28 risk-reducing mastectomies (RRM) and 24 risk-reducing salpingo-oophorectomies (RRSO). A substantial proportion of these were funded by non-governmental organizations, while the rest were covered by public health insurance (as adjuvant treatment), private health insurance or the patient herself. Regarding BC screening, after excluding 78 patients because of active BC treatment, bilateral mastectomy or male sex, 92% of eligible patients followed NCCN recommendations. No differences in the performance of RRS or BC screening strategies were found according to type of healthcare delivery.

Conclusion: In this cohort, an adequate adherence to recommended screening strategies was observed but only one-third of recommended RRS were performed. Notably, type of healthcare was not a determining factor for the adherence to NCCN's recommended prevention strategies, suggesting that economical barriers might not be the main limiting factor. Efforts to elucidate if sociocultural barriers limit adherence to RRS are being conducted in order to enhance standard of care at Mexican centers with GCRA programs.

Characteristics according to healthcare coverage.Private insurancePublic insurancep valueMutational status- Probands: carriers/tested32/117 (27%)67/320 (21%)NS- Relatives: carriers/tested10/42 (24%)42/97 (43%)0.036RRS- RRM performed/recommended9/24 (38%)19/65 (29%)NS- RRSO performed/recommended6/18 (33%)18/44 (41%)NS- RRS covered by NGOs0 (0%)11/37 (30%)0.022Current BC screening modality- Mammogram (MMG) ± US9 (41%)33 (65%)0.033- MRI ± MMG ± US9 (41%)6 (12%)- None3 (14%)1 (2%)- Unknown1 (5%)11 (22%)Follow BC screening recommendations- Yes19 (90%)37 (93%)NS- No2 (10%)3 (8%)

Citation Format: Dione Aguilar, Alejandro Aranda-Gutierrez, Ana S Ferrigno, Jeffrey N Weitzel, Kathleen N Blazer, Danielle Castillo, Josef Herzog, Rosa Mejia, Nancy L Sada-Villarreal, Servando Cardona, Mauricio Canavati-Marcos, Margarita Garza-Montemayor, Cynthia Villarreal-Garza. Genetic cancer risk assessment and its impact on the uptake of cancer risk reduction strategies: The experience of a Mexican center [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 PS8-25.

Abstract PS16-29: Clinicopathological features of PALB2 and BRCA2 mutation carriers with breast cancer

Background: The PALB2 gene is recognized as one of the most clinically relevant moderate to high penetrance breast cancer (BC) predisposition genes. Its product, PALB2, plays a crucial role in the homologous recombination pathway as a partner and localizer of BRCA2. Previous studies have reported significant frequencies of germline PALB2 and BRCA2 pathogenic variants (PVs) in Hispanic populations. However, no study has yet compared the baseline clinicopathological features of Mexican BC patients who carry PVs in these closely related genes.

Methods: Medical records of BC patients from two centers located in Monterrey, Mexico who underwent a next-generation sequencing panel for BC predisposition genes (APC, ATM, BRCA1, BRCA2, BRIP1, CHEK2, CDH1, CDKN2A, MLH1, MSH2, MSH6, MUTYH, NF1, PALB2, PMS2, PTEN, RAD50, RAD51C, RAD51D, TP53) based on NCCN recommendations were reviewed. Patients with germline PVs in PALB2 or BRCA2 were considered eligible. Fisher’s exact and Mann Whitney U tests were employed to evaluate differences between groups based on mutation status.

Results: Between 2014 and 2019, a total of 8 PALB2 (1.8%) and 24 BRCA2 (5.5%) pathogenic mutation carriers were identified from 437 BC cases. Baseline clinicopathological features are shown in Table 1. Overall, no statistically significant differences were observed between groups. The most common germline PVs were c.2167_2168delAT, p.Met723fs, frameshift mutation for PALB2 (57% of cases) and c.274C&gt;T, p.Gln92Ter, nonsense mutation for BRCA2 (30% of cases). Of note, one male BC case occurred in a PALB2 mutation carrier, representing 13% (1/8) of BC cases in this carrier group and the only male BC case (out of three) associated with a germline PV.

Conclusion: This is the first report detailing the clinicopathological features of Mexican BC patients with germline PALB2 PVs. According to our findings, BC tumors in PALB2 mutation carriers share similar baseline characteristics with those diagnosed in BRCA2 mutation carriers. Long-term follow-up is required in order to determine if prognosis is similar between groups and to further solidify the clinical relevance of germline PALB2 PVs in the Mexican population.

Baseline clinicopathological features of PALB2 and BRCA2 mutation carriers with BCPALB2 mutation carriersBRCA2 mutation carriersMedian age at diagnosis (years)3938Median body mass index (kg/m2)2326Family history of BCYes5 (63%)19 (79%)No3 (38%)5 (21%)Clinical stageI2 (25%)2 (8%)II5 (63%)11 (46%)III08 (33%)IV1 (13%)3 (13%)Histological typeIDC6 (75%)22 (92%)Non-IDC2 (25%)2 (8%)Histological gradeG11 (13%)5 (21%)G24 (50%)10 (42%)G33 (38%)6 (25%)Missing03 (13%)Molecular subtypeHR+/HER2-6 (75%)11 (46%)HR+/HER2+04 (17%)HR-/HER2+00HR-/HER2-2 (25%)9 (38%)LateralityUnilateral8 (100%)21 (88%)Bilateral03 (13%)

Citation Format: Alejandro Aranda-Gutierrez, Ana S Ferrigno, Juan Carlos A. García Marrufo, Mariana Moncada-Madrazo, Analy Gomez-Picos, Cynthia Villarreal-Garza, Dione Aguilar. Clinicopathological features of PALB2 and BRCA2 mutation carriers with breast cancer [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 PS16-29.

Abstract PS8-23: Impact of genetic cancer risk assessment on males with breast cancer predisposing mutations

Background: The implementation of genetic cancer risk assessment (GCRA) has resulted in an increased identification of adult males with breast cancer (BC) predisposing mutations. However, its effect on adherence to cancer prevention strategies and the psychological impact of receiving a positive genetic test result have not been sufficiently explored in men. The aim of this study is to determine the impact of GCRA on men with BC predisposing mutations.

Methods: Men aged ≥18 years that underwent genetic testing between 2017 and 2019 in a center located in Monterrey, Mexico were invited to answer a telephone survey in which clinical information was collected. In addition, a section with an adapted Multidimensional Impact of Cancer Risk Assessment (MICRA) was incorporated. Total MICRA score was determined as the mean of items 1-21. Furthermore, seven sections were analyzed separately: distress (items 1-4 and 7-8), uncertainty (items 9-12, 14-17 and 20), positive experiences (items 5-6 and 18-19), understanding choices (item 13), testing regret (item 21), worry about children (items 22-23) and worry about cancer (items 24-25). Differences between categorical variables were explored using Mann Whitney U tests.

Results: A total of 31 patients were eligible for this study, of which 29 consented to participate. Of these, 15 were mutation carriers (8 BRCA1, 3 BRCA2, 2 ATM, 1 CHEK2 and 1 PALB2) with a median age of 45 years (range 20-71). Only one of the carriers surveyed had a personal history of BC. The median time elapsed from disclosure of positive carrier status to survey application was 13 months. Remarkably, 3/15 ignored their test result despite previous GCRA, and only 4/15 were able to identify the specific mutated gene. Most had disclosed their mutation status to close relatives (67%). Regarding psychological impact, 2/15 thought that their genetic test result had a significant impact in their life and 1/15 claimed that undergoing genetic testing generated feelings of anxiety or depression. In addition, two out of three childless carriers reported that their mutation status made them seriously doubt whether to have biological children. Notably, only 47% were aware about the mode of transmission of their mutation. Concerning medical support, 87% felt that the support offered by the medical team was sufficient, but only 60% considered that they had enough information about the implications of their carrier status. With respect to prevention strategies, 67% claimed to be unaware about the general recommendations according to their mutational status and age. Furthermore, 87% did not use sunscreen, 80% had never visited a dermatologist, 73% could not correctly identify suspicious signs for skin cancer, 8/11 (72%) of eligible patients did not perform routine breast self-exams, and 10/11 (91%) had not visited a physician for a clinical breast exam. In addition, 0/6 (0%) of the eligible patients had had a colonoscopy and 5/6 (83%) eligible patients had not undergone screening for prostate cancer. Concerning the MICRA score, patients with BC predisposing mutations had a higher total mean score than non-carriers (21.7 vs. 14.3; p=0.01), particularly due to the positive experiences subscale (11.5 vs. 5.4; p=0.01).

Conclusion: Low awareness and poor adherence to recommended prevention strategies were found in male mutation carriers despite a high impact of GCRA in this group. Hence, efforts to elucidate the specific barriers that limit adherence to these strategies in men are warranted.

MICRA scores. Results are shown as mean (standard deviation).Mutation carriers (n=15)Non-carriers (n=14)p valueTotal score21.7 (8.5)14.3 (7.8)0.008Distress subscale2.1 (4.0)1.1 (1.9)0.617Uncertainty subscale6.0 (6.3)5.6 (7.1)0.603Positive experiences subscale11.5 (5.2)5.4 (7.2)0.013Understanding choices item2.0 (2.2)2.1 (2.1)0.841Testing regret item0.1 (0.3)0.0 (0.0)0.779Worry about children section2.5 (3.1)3.7 (3.3)0.569Worry about cancer section5.0 (0.0)5.0 (0.0)&gt;0.99

Citation Format: Ana S Ferrigno, Alejandro Aranda-Gutierrez, Mariana Moncada-Madrazo, Arantza Montemayor-Solis, Julia S Arango-Vasquez, Juan CA Garcia-Marrufo, Lourdes Martinez-Ordaz, Cynthia Villarreal-Garza, Dione Aguilar. Impact of genetic cancer risk assessment on males with breast cancer predisposing mutations [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 PS8-23.

Young Women With Breast Cancer in Mexico: Results of the Pilot Phase of the Joven & Fuerte Prospective Cohort

PURPOSE

The pilot-phase report of the Joven & Fuerte prospective cohort broadly characterizes and assesses the needs of Mexican young women with breast cancer (YWBC).

PATIENTS AND METHODS

Women age ≤ 40 years with nonmetastatic primary breast cancer were consecutively accrued from 2 hospitals. Data were collected at the first/baseline oncology visit and 2 years later using a sociodemographic survey, European Organisation for Research and Treatment of Cancer Quality-of-Life (QOL) Questionnaire Core 30 (QLQ-C30) and Breast Cancer-Specific QOL Questionnaire (QLQ-BR23), Hospital Anxiety and Depression Scale (HADS), Female Sexual Functioning Index (FSFI), Sexual Satisfaction Inventory, and patients' medical records. Pearson χ2 and 2-sided t tests were used for statistical analysis. An unadjusted P value < .05 was considered significant.

RESULTS

Ninety patients were included, all with government health care coverage. Most had low monthly household incomes (98%) and at least a high school education (59%). There was a considerable prevalence of unpartnered patients (36%) and unmet parity (25%). Patients' most common initial symptom was a palpable mass (84%), and they were most frequently diagnosed with stage III disease (48%), with 51% having had a physician visit ≤ 3 months since detection but 39% receiving diagnosis > 12 months later. At baseline, 66% of patients were overweight/obese, and this proportion had significantly increased by 2 years (P < .001). Compared with baseline, global QLQ-C30 had improved significantly by 2 years (P = .004), as had HADS-Anxiety (P < .001). However, both at baseline and at 2 years, nearly half of patients exhibited FSFI sexual dysfunction.

CONCLUSION

These preliminary findings demonstrate that YWBC in Mexico have particular sociodemographic and clinicopathologic characteristics, reinforcing the necessity to further describe and explore the needs of these young patients, because they may better represent the understudied and economically vulnerable population of YWBC in limited-resource settings.

Landscape of Germline Mutations in DNA Repair Genes for Breast Cancer in Latin America: Opportunities for PARP-Like Inhibitors and Immunotherapy

Germline mutations in BRCA1 and BRCA2 (BRCA1/2) genes are present in about 50% of cases of hereditary breast cancer. Proteins encoded by these genes are key players in DNA repair by homologous recombination (HR). Advances in next generation sequencing and gene panels for breast cancer testing have generated a large amount of data on gene variants implicated in hereditary breast cancer, particularly in genes such as PALB2, ATM, CHEK2, RAD51, MSH2, and BARD1. These genes are involved in DNA repair. Most of these variants have been reported for Caucasian, Jewish, and Asian population, with few reports for other communities, like those in Latin American (LA) countries. We reviewed 81 studies from 11 LA countries published between 2000 and 2019 but most of these studies focused on BRCA1/2 genes. In addition to these genes, breast cancer-related variants have been reported for PALB2, ATM, CHEK2, BARD1, MLH1, BRIP1, MSH2, NBN, MSH6, and PMS2 genes. Some of these variants are unique to LA populations. This analysis may contribute to enhance breast cancer variant characterization, and thus to find therapies and implement precision medicine for LA communities.

"Joven & Fuerte": Program for Young Women with Breast Cancer in Mexico - Initial Results

Despite the high rates of breast cancer among young Mexican women, their special needs and concerns have not been systematically addressed. To fulfill these unsatisfied demands, we have developed "Joven & Fuerte: Program for Young Women with Breast Cancer in Mexico," the first program dedicated to the care of young breast cancer patients in Latin America, which is taking place at the National Cancer Institute of Mexico and the two medical facilities of the Instituto Tecnológico y de Estudios Superiores de Monterrey. The program was created to optimize the complex clinical and psychosocial care of these patients, enhance education regarding their special needs, and promote targeted research, as well as to replicate this program model in other healthcare centers across Mexico and Latin America. From November 2013 to February 2017, the implementation of the "Joven & Fuerte" program has delivered specialized care to 265 patients, through the systematic identification of their particular needs and the provision of fertility, genetic, and psychological supportive services. Patients and families have engaged in pedagogic activities and workshops and have created a motivated and empowered community. The program developed and adapted the first educational resources in Spanish dedicated for young Mexican patients, as well as material for healthcare providers. As for research, a prospective cohort of young breast cancer patients was established to characterize clinicopathological features and psychosocial effects at baseline and during follow-up, as a guide for the development of specific cultural interventions addressing this vulnerable group. Eventually, it is intended that the program's organization and structure can reach national and international interactions and serve as a platform for other countries.

Evidence of melatonin synthesis in the ram reproductive tract

Melatonin is a ubiquitous molecule found in a wide range of fluids, one of them being ram seminal plasma, in which it can reach higher concentrations than those found in blood, suggesting an extrapineal secretion by the reproductive tract. In order to identify the source of the melatonin found in ram seminal plasma, we first tried to determine whether the melatonin levels were maintained during the day. For this purpose, melatonin concentrations were measured in seminal plasma obtained from first ejaculates of six rams at 6:00 a.m. in total darkness, at 10:00 a.m. and at 14:00 p.m. The melatonin concentration was higher (p < 0.05) in ejaculates collected at 6:00 a.m. than at 10:00 and 14:00. There was no statistical difference between the latter. To further corroborate an extrapineal secretion of melatonin, the presence of the two key enzymes involved in melatonin synthesis, arylalkylamine-N-acetyltransferase (AANAT) and N-acetylserotonin-O-methyltransferase (ASMT) was analyzed by RT-PCR, q-PCR and Western-blot in ram testes, epididymis, and accessory glands. The RT-PCR showed the presence of the m-RNA codifying both AANAT and ASTM in all the tissues under study, but the q-PCR and Western-blot revealed that gene expression of these enzymes was significantly higher in the testis (p < 0.05). Immunohistochemistry confirmed the presence of AANAT and ASMT in the testis and revealed that they were found in the Leydig cells, spermatocytes, and spermatids. Also, measurable levels of melatonin were found in testicular tissue and the tail of the epididymis. In conclusion, our study indicates that the testes are one of the likely sources of the high levels of melatonin found in ram seminal plasma, at least during the day.

Short-term additional enfuvirtide therapy is associated with a greater immunological recovery in HIV very late presenters: a controlled pilot study

OBJECTIVES

To evaluate whether the addition of enfuvirtide to standard highly active antiretroviral therapy (HAART) could confer immunovirological benefits in human immunodeficiency virus (HIV)-infected very late presenters. The current study is an open comparative therapeutic trial of standard protease inhibitor (PI)-based HAART ± additional enfuvirtide in treatment-naïve deeply immunologically impaired HIV-positive patients.

METHODS

Very late presenters (CD4 <50/mm(3)), without tuberculosis and neoplasms, were alternatively allocated to two nucleoside reverse transcriptase inhibitors (NRTIs) and lopinavir/ritonavir without (control arm, CO) or with (ENF arm) enfuvirtide 90 mg bid. Enfuvirtide was administered until the achievement of viral load <50 copies/ml and for at least 24 weeks. The primary objective was the magnitude of CD4+ cell recovery at 6 months. HIV RNA was intensively monitored in the first month, and, thereafter, monthly, as for CD4+ cell count and percentage, clinical data, and plasma drug concentrations.

RESULTS

Of 22 enrolled patients (11 per arm), 19 completed the study (10 in the ENF arm). Baseline CD4+ cell counts and % were comparable, with 20 CD4+/mm(3) (12-37) and a percentage of 3.3 (1.7-7.1) in the ENF arm, and 16 CD4+/mm(3) (9-29) and a percentage of 3.1 (2.3-3.8) in the CO arm, respectively. The baseline viral load was also comparable between the two arms, with 5.77 log10 (5.42-6) and 5.39 log10 (5.06-6) in the ENF and CO arms, respectively. Enfuvirtide recipients had higher CD4+ percentage at week 8 (7.6 vs. 3.6%, p = 0.02) and at week 24 (10.7 vs. 5.9%, p = 0.02), and a greater CD4+ increase at week 24 (207 vs. 134 cells/mm(3), p = 0.04), with 70% of enfuvirtide intakers versus 12.5% of controls who achieved a CD4+ cell count >200/mm(3) (p = 0.01). At 48 weeks, patients in the ENF arm had CD4+ cell counts higher than controls (251 vs. 153cells/mm(3), p = 0.04) and were also found to be faster in reaching a CD4 cell count over 200/mm(3): 18 (8-24) versus 48 (36-108) weeks (p = 0.01). Viral load decay at week 4 was greater in the ENF arm (-3 vs. -2.2 log, p = 0.04), while the proportion of patients with viral load <50 copies/ml at week 24 was comparable.

CONCLUSIONS

In this pilot study, the addition of enfuvirtide to a lopinavir-based HAART was shown to be associated with a significantly faster and greater immunological recovery in newly discovered HIV-positive patients with very low CD4+ cell counts. Induction strategies using an enfuvirtide-based approach in such subjects warrant further investigation.

Transgenic tomato expressing interleukin-12 has a therapeutic effect in a murine model of progressive pulmonary tuberculosis

Host control of mycobacterial infection, in both human and mouse models, has been shown to be associated with the production of interferon (IFN)-gamma by CD4(+) T cells. Interleukin (IL)-12 is known to be a crucial cytokine in the differentiation of IFN-gamma-producing T helper 1 (Th1) cells. To determine whether continuous administration of IL-12 expressed in transgenic tomato (TT-IL-12) has therapeutic efficacy in a murine model of pulmonary tuberculosis, BALB/c mice were infected with either Mycobacterium tuberculosis H37Rv strain or a multi-drug-resistant clinical isolate (MDR) and treated with a daily oral dose of TT-IL12 crude fruit extracts. For the early H37Rv infection, TT-IL-12 administration was started 1 day before infection and continued for 60 days. In the H37Rv or MDR late infection, treatment was started 60 days after infection and continued for another 60 days. In both phases of infection, TT-IL-12 administration resulted in a reduction of bacterial loads and tissue damage compared with wild-type tomato (non-TT). The Th1 response was increased and the Th2 response was reduced. In the late infection, a long-term treatment with TT-IL-12 was necessary. We demonstrate that TT-IL-12 increases resistance to infection and reduces lung tissue damage during early and late drug-sensitive and drug-resistant mycobacterial infection.

The metabolic syndrome and the heart--a considered opinion

The metabolic syndrome (MS) is a multifactorial, heterogeneous group of risk factors for the development of cardiovascular disease. Here we review the evidence in support of the hypothesis that metabolic dysregulation of the body as a whole leads to contractile dysfunction of the heart due to an imbalance of substrate uptake (increased) and substrate oxidation (decreased). The consequences of this imbalance were already recognized 150 years ago by Virchow when he described "fatty atrophy" of the heart as a "true metamorphosis of the heart muscle cell."

Night-time and daytime atypical manifestations of gastro-oesophageal reflux disease: frequency, severity and impact on health-related quality of life

BACKGROUND

Respondents with gastro-oesophageal reflux disease (GERD) report having a variety of atypical manifestations. The relationship between these manifestations and disease severity, night-time GERD and functioning has not been determined.

AIM

To determine if atypical manifestations are related to increased disease severity, night-time GERD and decreased functioning.

METHODS

A web survey among US adults was conducted, using a validated GERD screener. Frequency of night-time and daytime typical symptoms (acid regurgitation and heartburn) and atypical manifestations were assessed. Respondents were classified as night-time GERD or daytime GERD based on typical symptom frequency. Prevalence of frequent atypical manifestations (> or =2 days or nights/week) was assessed.

RESULTS

Gastro-oesophageal reflux disease cases had a higher prevalence of each atypical manifestation (P < 0.05 for all) compared with controls. Night-time GERD respondents had a higher prevalence of atypical manifestations compared with daytime GERD respondents (P < 0.05 for most manifestations) and the prevalence of atypical manifestations increased with GERD symptom severity (P < 0.05 for most). Those with atypical manifestations reported lower functioning scores (P < 0.05 for most).

CONCLUSIONS

Respondents with typical GERD symptoms commonly report atypical manifestations, especially those with night-time symptoms and those with greater underlying GERD severity. Respondents with GERD and atypical manifestations had more impaired functioning than those with typical symptoms only.

Immunological responses and protective immunity against tuberculosis conferred by vaccination of Balb/C mice with the attenuated Mycobacterium tuberculosis (phoP) SO2 strain

The Mycobacterium tuberculosis phoP mutant strain SO2 has been shown previously to be more attenuated than Mycobacterium bovis bacillus Calmette-Guérin (BCG) and confers protective immunity against tuberculosis in mice and guinea pig models. In this study we have investigated the survival and immunological responses of Balb/c mice infected with the M. tuberculosis SO2 strain. All Balb/C mice survived intratracheal infection with M. tuberculosis SO2 strain under conditions where all the mice infected with the parental M. tuberculosis MT103 had died after 9 weeks. Infection of Balb/c mice with M. tuberculosis SO2 was associated with comparatively lower levels of interferon (IFN)-gamma, interleukin (IL)-4 and tumour necrosis factor (TNF)-alpha and higher levels of inducible nitric oxide synthase (iNOS) during the late stage of infection, when compared with M. tuberculosis MT103 infection. The delayed-type hypersensitivity (DTH) response against M. tuberculosis culture filtrates was similar in mice infected with either the M. tuberculosis phoP SO2 strain or M. tuberculosis MT103. The protective efficacy of M. tuberculosis SO2 was compared with M. bovis BCG when delivered subcutaneously to groups of Balb/C mice. Following intratracheal challenge with M. tuberculosis H37Rv, protection was generated by 60 days post-challenge in mice vaccinated with either vaccine. At day 120 post-challenge the levels of protection were still significantly greater when compared with the non-vaccinated control group. The levels of protection conferred by vaccination with M. tuberculosis SO2 or with M. bovis BCG were similar, as measured by granuloma coalescence and pneumonia in addition to growth reduction of M. tuberculosis H37Rv.

Consequences of frequent nocturnal gastro-oesophageal reflux disease among employed adults: symptom severity, quality of life and work productivity

BACKGROUND

Effects of frequent nocturnal symptoms of gastro-oesophageal reflux disease (GERD-FNS) on health-related quality of life (HRQOL) and work productivity are not well documented.

AIM

To assess symptom severity, production loss, and HRQOL among employed adults with and without GERD-FNS.

METHODS

Using several validated outcome measures in a web survey design, GERD was pre-specified as GERD Symptom and Medication Questionnaire score >9, and > or =1 episode of heartburn or acid regurgitation during the preceding week. GERD-FNS patients were those reporting > or =2 symptom-nights during the previous week; their outcomes were compared with those of patients having minimal or no nocturnal symptoms (GERD-NNS) and vs. non-GERD controls.

RESULTS

Data were collected from 1002 GERD patients (476 GERD-FNS, 526 GERD-NNS) and 513 controls. Severe symptoms were more common, sleep abnormalities were more frequent (P < 0.0001) and SF-36 scores lower (P < 0.05, all scores) among GERD-FNS patients vs. GERD-NNS patients. GERD-related work loss was greater among those with GERD-FNS vs. GERD-NNS (P < 0.0001). Work loss and functional limitations were more pronounced when comparing GERD-FNS cases vs. non-GERD controls.

CONCLUSION

Employed adults with frequent nocturnal GERD report more severe symptoms, and are associated with impaired sleep, HRQOL and work productivity compared with controls and patients with minimal or no nocturnal symptoms.

Correlation of virulence, lung pathology, bacterial load and delayed type hypersensitivity responses after infection with different Mycobacterium tuberculosis genotypes in a BALB/c mouse model

One of the most intriguing aspects of tuberculosis is that the outcome of an infection with M. tuberculosis (TB) is highly variable between individuals. The possibility of differences in virulence between M. tuberculosis strains or genotypes has only recently been studied. There is evidence of multifactorial genetic predisposition in humans that influences the susceptibility to tuberculosis. A better understanding of differences in virulence between M. tuberculosis genotypes could be important with regard to the efforts at TB control and the development of improved antituberculosis vaccines. Survival, lung pathology, bacterial load and delayed type hypersensitivity (DTH) responses of BALB/c mice after intratracheal infection with any of 19 different M. tuberculosis complex strains of 11 major genotype families were studied. The results indicate that among genetically different M. tuberculosis strains a very broad response was present with respect to virulence, pathology, bacterial load and DTH. 'Low'-responders were the H37Rv, Canetti, Beijing-1 strains, while Beijing-2,3, Africa-2 and Somalia-2 strains were 'high'-responders. A severe pathological response correlates with a high mortality and a high CFU counts in lungs, but poorly with the degree of the DTH response.

Patient- versus physician-reported outcomes in rheumatoid arthritis patients treated with recombinant interleukin-1 receptor antagonist (anakinra) therapy

OBJECTIVES

To determine whether patient-reported outcomes may differentiate treatment response better than physician-reported outcomes for rheumatoid arthritis (RA) patients being treated with anakinra.

METHODS

A meta-analysis was conducted using data obtained from three separate randomized controlled clinical trials (RCTs) (n = 1007). Outcomes from 6-month assessments were grouped into four categories: American College of Rheumatology (ACR) response criteria, patient-reported measures (patient-reported pain, patient global assessment, and assessment of physical function using the Health Assessment Questionnaire), physician-reported measures (tender and swollen joint counts and physician global assessment), and laboratory tests (C-reactive protein and erythrocyte sedimentation rate). Effect sizes were calculated using changes from baseline and pooled standard deviations for each of these types of outcome.

RESULTS

Active treatment with anakinra was superior to placebo by ACR(20) responses in all three RCTs. Effect sizes for patient-reported outcomes were greater than for physician-reported outcomes, and also greater than ACR(20) in three of five anakinra cohorts. Across the RCTs, placebo responses were greater with physician-reported than with patient-reported outcomes. In the two studies evaluating patients with longer-standing disease, differences between pooled effect sizes for patient-reported and physician-reported outcomes were even more pronounced.

CONCLUSIONS

In three pivotal RCTs, active treatment with anakinra resulted in greater improvements in patient-reported than physician-reported outcomes compared with placebo. These observations confirm those previously reported from RCTs evaluating conventional DMARDs, demonstrating better discrimination of treatment effect with patient-reported outcomes.

A marked difference in pathogenesis and immune response induced by different Mycobacterium tuberculosis genotypes

In the last decade, an unprecedented genetic diversity has been disclosed among Mycobacterium tuberculosis strains found worldwide. However, well-conserved genotypes seem to prevail in areas with high incidence of tuberculosis. As this may be related to selective advantages, such as advanced mechanisms to circumvent [M. bovis Bacille Calmette-Guerin (BCG)-induced] host defence mechanisms, we investigated the influence of strain diversity on the course of experimental disease. Twelve M. tuberculosis strains, representing four major genotype families found worldwide today, and the laboratory strain H37Rv were each used to infect BALB/c mice by direct intratracheal injection. Compared with H37Rv, infections with Beijng strains were characterized by extensive pneumonia, early but ephemeral tumour necrosis factor-alpha (TNF-alpha) and inducible isoform of nitric oxide synthetase (iNOS) expression, and significantly higher earlier mortality. Conversely, Canetti strains induced limited pneumonia, sustained TNF-alpha and iNOS expression in lungs, and almost 100% survival. Strains of the Somali and the Haarlem genotype families displayed less homogeneous, intermediate rates of survival. Previous BCG vaccination protected less effectively against infection with Beijing strains than against the H37Rv strain. In conclusion, genetically different M. tuberculosis strains evoked markedly different immunopathological events. Bacteria with the Beijing genotype, highly prevalent in Asia and the former USSR, elicited a non-protective immune response in mice and were the most virulent. Future immunological research, particularly on candidate vaccines, should include a broad spectrum of M. tuberculosis genotypes rather than a few laboratory strains.

An ORF from Bacillus licheniformis encodes a putative DNA repressor

The complete sequence of a reading frame adjacent to the endo-beta-1,3-1,4-D-glucanase gene from Bacillus licheniformis is reported. It encodes a putative 171 amino acid residues protein with either, low significant sequence similarity in data banks or the corresponding orthologue in the recently sequenced Bacillus subtilis genome. Computer analyses predict a canonical Helix-Turn-Helix motif characteristic of bacterial repressors/DNA binding proteins. A maxicells assay shows that the encoded polypeptide is expressed. A DNA-protein binding, assay performed by gel electrophoresis shows that the expressed protein specifically binds to Bacillus licheniformis DNA.

Persistence of DNA from Mycobacterium tuberculosis in superficially normal lung tissue during latent infection

BACKGROUND

A third of the world's population has latent infection with Mycobacterium tuberculosis, and in areas of low endemicity, most cases of active tuberculosis arise as a result of reactivation of latent bacilli. We sought to establish the cellular location of these latent organisms to facilitate their elimination.

METHODS

We applied in-situ PCR to sections of macroscopically normal lung tissue from 13 individuals from Ethiopia and 34 from Mexico who had died from causes other than tuberculosis. Sections of lung tissue from six Norwegian individuals (ie, individuals from a non-endemic population) acted as negative controls, and six Ethiopian tuberculosis cases acted as positive controls.

FINDINGS

Control necropsy samples from the Norwegian individuals were all negative by in-situ PCR and conventional PCR, whereas all samples from known Ethiopian tuberculosis cases were positive by both methods. However, in macroscopically normal lung tissue from Ethiopian and Mexican individuals without tuberculous lesions, the in-situ PCR revealed five of 13 and ten of 34 positive individuals, respectively. These results were confirmed by conventional PCR with extracted DNA. Positive cells included alveolar and interstitial macrophages, type II pneumocytes, endothelial cells, and fibroblasts.

INTERPRETATION

M. tuberculosis can persist intracellularly in lung tissue without histological evidence of tuberculous lesions. M. tuberculosis DNA is situated not only in macrophages but also in other non-professional phagocytic cells. These findings contradict the dominant view that latent organisms exist in old classic tuberculous lesions, and have important implications for strategies aimed at the elimination of latent and persistent bacilli.

[Diagnosis of mesial temporal sclerosis with magnetic resonance imaging]

INTRODUCTION

Mesial temporal sclerosis (MTS) is a progressive drug-resistant epileptic syndrome which requires rapid, effective diagnosis and treatment. Histologically there is atrophy and gliosis of the hippocampus.

OBJECTIVE

To establish magnetic resonance (MR) imaging guidelines for correct diagnosis.

PATIENTS AND METHODS

We made a prospective study of 78 patients with drug-resistant temporal lobe epilepsy (44 women and 34 men; age 6-66 years, mean 31 years). Using a magnet of 1.5 Teslas paracoronal sections were made of the hippocampus with T1 volumetric with inversion-recovery, FLAIR (fluid-attenuated inversion-recovery) and T2 relaxometry. A control group of 30 healthy volunteers was established. The reduction in volume and hippocampal T2 hyperintensity were considered to be MTS diagnosed on MR.

RESULTS

No hippocampal differences were observed among the healthy volunteers. The confidence intervals (mean +/- 1.96 SD) were: right volume: 4.169-5.911 mm3; left volume: 4.097-5.940 mm3; time of T2 relaxation: 98-113 ms. MTS was observed in 42 patients (54%): 24 left, 14 right and four asymmetrical bilateral. The results of the diagnostic validity (sensitivity/specificity) were: T1 volumetric 91/92%, FLAIR 93.5/98% and T2 relaxometry 91/92%. There was atrophy of other extrahippocampal structures in five cases of MTS; 10 patients with MTS (23.5%) had another extrahippocampal lesion associated (dual pathology), particularly migration disorders; 21 patients (27%) had lesions without MTS (tumors, alterations of migration, nonspecific gliosis) and in 15 cases (19%) there were no abnormal findings. A total of 27 patients were operated on: 22 with MTS (21 had diagnostic MR, one case had no abnormal findings), four cases had tumors and one had cortical dysplasia.

CONCLUSION

The combination of quantitative techniques (T1 volumetric with inversion-recovery and T2 relaxometry) and FLAIR optimize MTS diagnosis using MR.

Pre-arrest heparinization and ventilation during warm ischemia preserves lung function in non-heart-beating donors

BACKGROUND/PURPOSE

To solve the problem of donor scarcity, many attempts have been made including improved community education, relaxed organ acceptance criteria, increased reliance on single lung transplantation, and the use of partial organ donation. Unfortunately, these efforts have produced only modest increases in lung allograft availability; therefore, the so-called non-heart-beating organ donation must be considered. The aim of this study is to assess the viability of the non-heart-beating donor (NHBD) lung transplant rat model and determine the best strategy to manage the donor before and after cardiac arrest.

METHODS

Fifty-five inbred Fischer rats were used as donors and recipients in an isogenic model of left lung transplantation. The rats were divided into 6 groups (n = 5): group I, normal controls without transplant; group II, heart-beating donor controls (HBD); group III, NHBD, no heparin, no ventilation during warm ischemia; group IV, NHBD, heparin, no ventilation; group V, NHBD, no heparin, ventilation; group VI, NHBD, heparin, ventilation. All lungs were stored at 4 degrees C for 4 hours. Animals were killed 24 hours after implantation. Gas exchange, pulmonary artery pressure, compliance, chest x-ray score, and histological score were assessed.

RESULTS

Heparinized and ventilated animals during warm ischemia (group VI) had similar performance than those transplanted without warm ischemia time in a scenario of heart-beating donor (group II). Groups III, IV, and V transplanted lungs showed severe damage.

CONCLUSIONS

The authors conclude that the rat lung transplantation model is useful to study the phenomena that occur in a setting of transplantation using NHBD and that heparinization and ventilation before cardiac arrest is the best strategy to manage non-heart-beating donors in this model.

Design and validation of a new image analysis method for automatic quantification of interstitial fibrosis and glomerular morphometry

Interstitial fibrosis and morphologic changes in kidney glomeruli, the structural effects of many diseases, lead to significant pathologic alterations. A reliable and objective method to accurately quantify the extent of interstitial fibrosis and the degree of alteration in glomerular morphology is needed for both clinical practice and experimental work. The morphometric methods of quantification described to date are time-consuming and require trained personnel. This article describes the design and validation of an image analysis-based application (Fibrosis HR) for automatically and rapidly quantifying interstitial fibrosis and glomerular morphology in the same tissue section stained with Sirius red. The image processing algorithms described herein automatically segment interstitial fibrosis and mesangial matrix using automatic thresholding and morphologic filtering. The glomerular region is extracted by a simple interactive step and an automatic mathematical morphology algorithm, whereas the glomerular tuft is automatically segmented with automatic thresholding and a sequence of Boolean and mathematical morphology operations. All extracted areas are automatically quantified in absolute (microm2) and relative (%) values. For validation of this method, interstitial fibrosis, mesangial matrix, and glomerular and glomerular tuft areas were manually segmented and their quantifications statistically compared with those obtained automatically. Statistical analyses showed significant intra- and interoperator variability in manual segmentation of interstitial fibrosis, mesangial matrix, and glomerular tuft areas. Automatic quantifications of the same areas did not differ significantly from their mean manual evaluations. There was no significant intra- or interoperator variability in the interactive identification of the glomerular region. In conclusion, Fibrosis HR produces robust, fully reproducible, accurate, objective, and reliable quantifications, which facilitate the evaluation of in vivo experimental models of renal interstitial and glomerular pathologies and improve the accuracy of clinicopathologic analyses of renal diseases in human biopsies.

Relationship between P-glycoprotein expression and cyclosporin A in kidney. An immunohistological and cell culture study

P-glycoprotein (P-gp), encoded in humans by the mdr-1 gene, acts physiologically as an efflux pump to expel hydrophobic substances from cells. This glycoprotein is closely related to multidrug resistance in tumor cells and can be modulated by cyclosporin A (CsA). We investigated the relationship between CsA and P-gp in 52 renal allograft biopsies and in cultures of Madin-Darby canine kidney (MDCK) renal tubule cells to determine whether the intrarenal accumulation of CsA or chronic stimulation with the drug modified the expression of P-gp. Expression of P-gp and CsA was analyzed by immunohistochemistry. Immunostaining was evaluated semiquantitatively. Modulation of P-gp in MDCK cells after chronic stimulation with CsA for 7, 30, and 60 days was analyzed by flow cytometry. P-gp and CsA immunostaining in renal post-transplant biopsies showed considerable overlap in all cases (Spearman's test, r = 0.577, P < 0.001). After 7 days in vitro, the number of cells expressing P-gp increased progressively; a further increase in mean fluorescence was found after 60 days (P < 0.001, Student's t-test). Our findings suggest that in non-neoplastic cells, CsA may stimulate P-gp as a mechanism of detoxification. Individual differences in the adaptive responses to glycoprotein may be responsible for the appearance of nephrotoxicity or a CsA-resistant rejection reaction in cases of overexpression on lymphocytes and macrophages.