Building momentum through networks: Bioimaging across the Americas.

In September 2023, the two largest bioimaging networks in the Americas, Latin America Bioimaging (LABI) and BioImaging North America (BINA), came together during a 1-week meeting in Mexico. This meeting provided opportunities for participants to interact closely with decision-makers from imaging core facilities across the Americas. The meeting was held in a hybrid format and attended in-person by imaging scientists from across the Americas, including Canada, the United States, Mexico, Colombia, Peru, Argentina, Chile, Brazil and Uruguay. The aims of the meeting were to discuss progress achieved over the past year, to foster networking and collaborative efforts among members of both communities, to bring together key members of the international imaging community to promote the exchange of experience and expertise, to engage with industry partners, and to establish future directions within each individual network, as well as common goals. This meeting report summarises the discussions exchanged, the achievements shared, and the goals set during the LABIxBINA2023: Bioimaging across the Americas meeting.

Selection and Application of Aptamer Affinity for Protein Purification.

Aptamers are affinity-based oligonucleotide ligands raised against a target molecule, which might be of proteic or other nature. Aptamers are developed by using a reiterative in vitro selection procedure, named SELEX, in which the target is exposed to a combinatorial oligonucleotide combinatorial library. Target bound oligonucleotides are eluted, and PCR amplified followed by the next SELEX round. The process is repeated until no further increase in target binding affinity and specificity is achieved. Selected aptamers are identified and immobilized for protein purification. In view of their stability against denaturation and capability of renaturation, low costs of production, easiness of modification and stabilization, oligonucleotide aptamers are excellent tools as high-affinity ligands for applications of protein purification.

Pulmonary Neuroendocrine Neoplasms Overexpressing Epithelial-Mesenchymal Transition Mechanical Barriers Genes Lack Immune-Suppressive Response and Present an Increased Risk of Metastasis.

Typical carcinoids (TC), atypical carcinoids (AC), large cell neuroendocrine carcinomas (LCNEC), and small cell lung carcinomas (SCLC) encompass a bimodal spectrum of metastatic tumors with morphological, histological and histogenesis differences, The hierarchical structure reveals high cohesiveness between neoplastic cells by mechanical desmosomes barrier assembly in carcinoid tumors and LCNEC, while SCLC does not present an organoid arrangement in morphology, the neoplastic cells are less cohesive. However, the molecular mechanisms that lead to PNENs metastasis remain largely unknown and require further study. In this work, epithelial to mesenchymal transition (EMT) transcription factors were evaluated using a set of twenty-four patients with surgically resected PNENs, including carcinomas. Twelve EMT transcription factors (BMP1, BMP7, CALD1, CDH1, COL3A1, COL5A2, EGFR, ERBB3, PLEK2, SNAI2, STEAP1, and TCF4) proved to be highly expressed among carcinomas and downregulated in carcinoid tumors, whereas upregulation of BMP1, CDH2, KRT14 and downregulation of CAV2, DSC2, IL1RN occurred in both histological subtypes. These EMT transcription factors identified were involved in proliferative signals, epithelium desmosomes assembly, and cell motility sequential steps that support PNENs invasion and metastasis in localized surgically resected primary tumor. We used a two-stage design where we first examined the candidate EMT transcription factors using a whole-genome screen, and subsequently, confirmed EMT-like changes by transmission electron microscopy and then, the EMT-related genes that were differentially expressed among PNENs subtypes were predicted through a Metascape analysis by in silico approach. A high expression of these EMT transcription factors was significantly associated with lymph node and distant metastasis. The sequential steps for invasion and metastasis were completed by an inverse association between functional barrier created by PD-L1 immunosuppressive molecule and EMT transcriptional factors. Our study implicates upregulation of EMT transcription factors to high proliferation rates, mechanical molecular barriers disassembly and increased cancer cell motility, as a critical molecular event leading to metastasis risk in PNENs thus emerging as a promising tool to select and customize therapy.

Aptamer Applications in Emerging Viral Diseases.

Aptamers are single-stranded DNA or RNA molecules which are submitted to a process denominated SELEX. SELEX uses reiterative screening of a random oligonucleotide library to identify high-affinity binders to a chosen target, which may be a peptide, protein, or entire cells or viral particles. Aptamers can rival antibodies in target recognition, and benefit from their non-proteic nature, ease of modification, increased stability, and pharmacokinetic properties. This turns them into ideal candidates for diagnostic as well as therapeutic applications. Here, we review the recent accomplishments in the development of aptamers targeting emerging viral diseases, with emphasis on recent findings of aptamers binding to coronaviruses. We focus on aptamer development for diagnosis, including biosensors, in addition to aptamer modifications for stabilization in body fluids and tissue penetration. Such aptamers are aimed at in vivo diagnosis and treatment, such as quantification of viral load and blocking host cell invasion, virus assembly, or replication, respectively. Although there are currently no in vivo applications of aptamers in combating viral diseases, such strategies are promising for therapy development in the future.

Mutational Portrait of Lung Adenocarcinoma in Brazilian Patients: Past, Present, and Future of Molecular Profiling in the Clinic.

Objectives: Approximately 60% of lung adenocarcinomas (LAs) carry mutations that can guide treatment with tyrosine-kinase inhibitors (TKI) and other targeted therapies. Data on activating mutations in EGFR and other tyrosine-kinase receptor (TKR) genes in highly admixed populations, such as that of Brazil, are scarce. In this study, we comprehensively analyzed the actionable alteration profile of LA in Brazilian patients. Materials and Methods: EGFR driver mutation data were collected from a large Brazilian LA cohort covering an 8-year period of molecular testing in a single institution. Tests were performed using three distinct methods, and demographic and histopathological data were analyzed. For a subset of patients, driver mutations in KRAS, NRAS, and BRAF and gene fusions involving TKR genes (before TKI treatment) and EGFR T790M (after TKI treatment) were assessed. Results: EGFR mutations were detected in 25% of 1,316 LAs evaluated, with exon 19 deletions and exon 21 L858R TKI sensitizing mutations representing 72.5% of all mutations. Mutation rates were higher in women and non-smokers (p < 0.001). Next-generation sequencing was very sensitive, with a lower rate of inconclusive results compared with Sanger sequencing and pyrosequencing. EGFR/RAS/BRAF hotspot gene panels were applied in 495 LA cases and detected oncogenic mutations in 51.3% of samples, most frequently in EGFR (22.4%) and KRAS (26.9%). In subgroups of 36 and 35 patients, gene fusions were detected in 11.1% of tumors and EGFR T790M resistance mutations were detected in 59% of plasma samples from patients previously treated with TKI, respectively. Conclusion: This report provides the first comprehensive actionable alteration portrait of LA in Brazil. The high rate of actionable alterations in EGFR and other driver genes in LA reinforces the need to incorporate TKI guided by molecular diagnostics into clinical routines for patients in both public and private healthcare systems.

Variants in Epithelial-Mesenchymal Transition and Immune Checkpoint Genes Are Associated With Immune Cell Profiles and Predict Survival in Non-Small Cell Lung Cancer.

CONTEXT.­: Identification of gene mutations that are indicative of epithelial-mesenchymal transition and a noninflammatory immune phenotype may be important for predicting response to immune checkpoint inhibitors. OBJECTIVE.­: To evaluate the utility of multiplex immunofluorescence for immune profiling and to determine the relationships among tumor immune checkpoint and epithelial-mesenchymal transition genomic profiles and the clinical outcomes of patients with nonmetastatic non-small cell lung cancer. DESIGN.­: Tissue microarrays containing 164 primary tumor specimens from patients with stages I to IIIA non-small cell lung carcinoma were examined by multiplex immunofluorescence and image analysis to determine the expression of programmed death ligand-1 (PD-L1) on malignant cells, CD68+ macrophages, and cells expressing the immune markers CD3, CD8, CD57, CD45RO, FOXP3, PD-1, and CD20. Immune phenotype data were tested for correlations with clinicopathologic characteristics, somatic and germline genetic variants, and outcome. RESULTS.­: A high percentage of PD-L1+ malignant cells was associated with clinicopathologic characteristics, and high density of CD3+PD-1+ T cells was associated with metastasis, suggesting that these phenotypes may be clinically useful to identify patients who will likely benefit from immunotherapy. We also found that ZEB2 mutations were a proxy for immunologic ignorance and immune tolerance microenvironments and may predict response to checkpoint inhibitors. A multivariate Cox regression model predicted a lower risk of death for patients with a high density of CD3+CD45RO+ memory T cells, carriers of allele G of CTLA4 variant rs231775, and those whose tumors do not have ZEB2 mutations. CONCLUSIONS.­: Genetic variants in epithelial-mesenchymal transition and immune checkpoint genes are associated with immune cell profiles and may predict patient outcomes and response to immune checkpoint blockade.

Usefulness of complementary next-generation sequencing and quantitative immunohistochemistry panels for predicting brain metastases and selecting treatment outcomes of non-small cell lung cancer.

To demonstrate the usefulness of complementary next-generation sequencing (NGS) and immunohistochemistry (IHC) counting, we analyzed 196 patients with non-small cell lung cancer who underwent surgical resection and adjuvant chemotherapy. Formalin-fixed, paraffin-embedded samples of adenocarcinoma (ADC), squamous cell carcinoma, and large cell carcinoma were used to prepare tissue microarrays and were examined by protein H-score IHC image analysis and NGS for oncogenes and proto-oncogenes and genes of tumor suppressors, immune checkpoints, epithelial-mesenchymal transition factors, tyrosine kinase receptors, and vascular endothelial growth factors. In patients with brain metastases, primary tumors expressed lower PIK3CA protein levels. Overexpression of p53 and a higher PD-L1 protein H-score were detected in patients who underwent surgical treatment followed by chemotherapy as compared with those who underwent only surgical treatment The absence of brain metastases was associated with wild-type sequences of genes EGFR, CD267, CTLA-4, and ZEB1. The combination of protein overexpression according to IHC and mutation according to NGS was rare (ie, represented by a very low percentage of concordant cases), except for p53 and vascular endothelial growth factor. Our data suggest that protein levels detected by IHC may be a useful complementary tool when mutations are not detected by NGS and also support the idea to expand this approach beyond ADC to include squamous cell carcinoma and even large cell carcinoma, particularly for patients with unusual clinical characteristics. Conversely, well-pronounced immunogenotypic features seemed to predict the clinical outcome after univariate and multivariate analyses. Patients with a solid ADC subtype and mutated genes EGFR, CTLA4, PDCD1LG2, or ZEB1 complemented with PD-L1 or p53 protein lower expression that only underwent surgical treatment who develop brain metastases may have the worst prognosis.

Biomolecular analysis of matrix proteoglycans as biomarkers in non small cell lung cancer.

Matrix proteoglycans (PGs) have shown promise as biomarker in malignancies. We employed agarose gel eletrophoresis, quantitative real- time reverse transcription-polymerase chain reaction and immunohistochemistry to evaluate the content of sulfated glicosaminoglycans (chondroitin sulfate and heparan sulfate) and expression of PG (biglycan, glypican, perlecan, syndecan e versican) in patient-matched normal and tumor tissues obtained from resected specimens of lung cancer. A significant increase of heparan sulfate (HS) and chondroitin sulfate (CS) concentrations was found in tumor tissue samples when compared to normal lung tissue samples. HS was also significantly increased in adenocarcinomas compared to squamous cell carcinomas. PG gene expression, with exception of syndecan, were significantly decreased in tumor tissue compared to normal lung, coinciding with significant decrease of PG protein levels in tumor cells and stroma compared to normal lung tissue (Kappa coefficient 0.41, 0.42 and 0,28, respectively). Women patients (p = 0.02), non smokers (p = 0.05), T stage (p = 0.009), N stage (p = 0.03) and adenocarcinoma (p = 0.05) were associated with improved overall survival (OS). Patients presenting tumors with low concentration of sulfated GAG and high PGs levels presented better OS compared to patients with high concentration of sulfated GAG and low expression of PGs. Cox regression model controlled by gender, tobacco history and histological type, showed that patients with high perlecan and versican expression in tumor presented respectively high probability of life (ß risk 11.64; 1.27 to 15.90) and low risk of death (ß risk 0.11; 0.02-0.51). The combined approach suggest matrix (PGs) as biomarkers in lung cancer.

Lung cancer in Brazil: epidemiology and treatment challenges.

Lung cancer persists throughout the world as a major cause of death. In 2014, data from the Brazilian National Cancer Institute (INCA) estimated 16.400 new cases of lung cancer among men (second most common) and 10.930 new cases among women (fourth most common). These data are consistent for all Brazilian regions and reflect the trends of cancer in the country over the last decade. Brazil is a continental country, the largest in Latin America and fifth in the world, with an estimated population of >200 million. Although the discrepancy in the national income between rich and poor has diminished in the last 2 decades, it is still huge. More than 75% of the Brazilian population do not have private health insurance and rely on the national health care system, where differences in standard of cancer care are evident. It is possible to point out differences from the recommendations of international guidelines in every step of the lung cancer care, from the diagnosis to the treatment of advanced disease. This review aims to describe and recognize these differences as a way to offer a real discussion for future modifications and action points toward delivery of better oncology care in our country.

Mutational Profile and New IASLC/ATS/ERS Classification Provide Additional Prognostic Information about Lung Adenocarcinoma: A Study of 125 Patients from Brazil.

AIM: To show additional prognostic information about the mutational profile and new International Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society (IASLC/ATS/ERS) classification of adenocarcinoma (ADC) in patients without epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitor treatments. METHODS: In human lung ADC patients (n = 125), including 24 lepidic, 67 acinar, 23 papillary, and 11 solid predominant subtypes, EGFR and KRAS were sequenced, and anaplastic lymphoma kinase (ALK) rearrangements were screened using fluorescence in situ hybridization (FISH). RESULTS: EGFR was mutated in 21.6% of patients with 19.57% showing a mean expression. The most frequent EGFR mutation was a deletion in exon 19, followed by an L858R amino acid substitution in exon 21. KRAS was mutated in 26.4% of patients with 50% displaying mean expression. ALK rearrangement was detected in 6 patients (4.8%). Predominant acinar ADC was strongly associated with EGFR and KRAS mutation. Clinical stage, lymph node metastases, and EGFR mutation in exon 18 showed a significant difference in disease-free and overall survival, but only a trend significance for EGFR and KRAS mutations. Multivariate analysis revealed that men aged >71 years, with a history of smoking (<72 packs/year), clinical stage I/II, and acinar histologic subtype presented better survival than women aged ≤ 71 years, with a history of smoking (>72 packs/year), and having a predominant solid ADC and EGFR mutation in exon 18. CONCLUSIONS: These results indicate that the mutational profile and new IASLC/ATS/ERS classification provide additional prognostic information about lung ADC.

DNA nanoparticle-mediated thymulin gene therapy prevents airway remodeling in experimental allergic asthma.

Thymulin has been shown to present anti-inflammatory and anti-fibrotic properties in experimental lung diseases. We hypothesized that a biologically active thymulin analog gene, methionine serum thymus factor, delivered by highly compacted DNA nanoparticles may prevent lung inflammation and remodeling in a mouse model of allergic asthma. The DNA nanoparticles are composed of a single molecule of plasmid DNA compacted with block copolymers of poly-L-lysine and polyethylene glycol (CK30PEG), which have been found safe in a human phase I/II clinical trial. Thymulin plasmids were detected in the lungs of ovalbumin-challenged asthmatic mice up to 27days after administration of DNA nanoparticles carrying thymulin plasmids. A single dose of DNA nanoparticles carrying thymulin plasmids prevented lung inflammation, collagen deposition and smooth muscle hypertrophy in the lungs of a murine model of ovalbumin-challenged allergic asthma, leading to improved lung mechanics. In the present model of chronic allergic asthma, highly compacted DNA nanoparticles using thymulin analog gene modulated the inflammatory and remodeling processes improving lung mechanics.

Hyaluronidase splice variants are associated with histology and outcome in adenocarcinoma and squamous cell carcinoma of the lung.

Heterogeneity of hyaluronidase (HYAL) expression has been identified in tumors and shows promise as an indicator of disease progression. The expression profile of alternatively spliced forms of HYAL was evaluated in tumors and normal lung tissue from 69 resected tumors of patients with adenocarcinomas and squamous cell carcinomas. HYAL1-wild-type (wt) and variants 1 to 5, HYAL2-wt, and HYAL3-wt, and variants 1 to 3 were identified by polymerase chain reaction and direct sequencing. Different proportions of the 3 HYAL-wt and variants were expressed in tumor and normal lung tissues. HYAL1-wt was associated with a poorer prognosis and HYAL3-v1 with a better prognosis. HYAL splice variants are associated with histology and outcome, suggesting that strategies aimed at modulating their levels may be effective for lung cancer treatment.

Isoforms of hyaluronidases can be a predictor of a prostate cancer of good prognosis.

INTRODUCTION: Hyaluronidases (HAases) are enzymes related to cancer progression. Isoforms of HAases have been described as products of alternative splicing responsible for differences in enzyme activity. The heterogeneity of HAase expression has been identified in tumors and could be related to the differences in their biological behavior. METHODS: Thirty-seven patients subjected to radical prostatectomy for prostate cancer were divided into 2 groups for the analyses: Low (< or =6-18) and high (> or =7-19) Gleason score and tumor behavior; recurrence 15 and nonrecurrence 22, mean follow-up 52.6 months. CONCLUSION: A profile of HAase related to low Gleason score and non-tumor recurrence was characterized by expression of HYAL3-v1, HYAL1-v3, and HYAL3-v2. More studies should be made in order to confirm with larger series.