Clinicopathological and molecular profile of grade 3 gastroenteropancreatic neuroendocrine neoplasms

The 2019 Word Health Organization (WHO) subclassified grade 3 (G3) gastroenteropancreatic (GEP) neuroendocrine neoplasms (NEN) into neuroendocrine carcinoma (NEC) or tumours (G3 NET) based on morphology and proliferation. Yet, few data exist on molecular profiles for G3 NEN. We compared clinicopathological and molecular characteristics of these two groups. We retrospectively reviewed consecutive G3 GEP NEN patients and had their tumour tissues reviewed, reclassified as per the WHO 2019, and analyzed by a next-generation sequencing (NGS) panel. Between 2000 and 2019, 43 patients had pathology revision: 29 (67%) were NEC and 14 (33%) were G3 NET, with a 23% change in diagnosis. Median overal survival for G3 NET and NEC patients was 55.6 and 11.9 months, respectively (hazard ratio = 2.78 [95% confidence interval = 1.09-7.11], p = .042), which was confirmed by an adjusted analysis (hazard ratio = 2.90 NEC vs. G3 NET; p = .03). NGS was performed in 32 cases: 21 NEC and 11 G3 NET. Mutations in RB1 and PTEN were exclusively encountered in NEC. Median tumour mutational burden was 5 (0-67) mutations per megabase in NEC and 4.5 (0-9) among G3 NET. Microsatellite instability was found in 3 (14.3%) NEC cases. In conclusion, pathology revision is essential to estimate prognosis and therapeutic plan. G3 GEP NEN generally harbour low tumor mutation burden and fewer actionable mutations, but 14% of NEC cases were microsatellite unstable and could benefit from immune checkpoint inhibitors.

Genomics and epidemiology for gastric adenocarcinomas (GE4GAC): a Brazilian initiative to study gastric cancer

Gastric cancer (GC) is the fifth most common type of cancer worldwide with high incidences in Asia, Central, and South American countries. This patchy distribution means that GC studies are neglected by large research centers from developed countries. The need for further understanding of this complex disease, including the local importance of epidemiological factors and the rich ancestral admixture found in Brazil, stimulated the implementation of the GE4GAC project. GE4GAC aims to embrace epidemiological, clinical, molecular and microbiological data from Brazilian controls and patients with malignant and pre-malignant gastric disease. In this letter, we summarize the main goals of the project, including subject and sample accrual and current findings.

Is the Morphological Subtype of Extra-Pulmonary Neuroendocrine Carcinoma Clinically Relevant?

Extra-pulmonary neuroendocrine carcinomas (EP-NECs) are lethal cancers with limited treatment options. Identification of contributing factors to the observed heterogeneity of clinical outcomes within the EP-NEC family is warranted, to enable identification of effective treatments. A multicentre retrospective study investigated potential differences in "real-world" treatment/survival outcomes between small-cell (SC) versus (vs.) non-SC EP-NECs. One-hundred and seventy patients were included: 77 (45.3%) had SC EP-NECs and 93 (54.7%) had non-SC EP-NECs. Compared to the SC subgroup, the non-SC subgroup had the following features: (1) a lower mean Ki-67 index (69.3% vs. 78.7%; p = 0.002); (2) a lower proportion of cases with a Ki-67 index of ≥55% (73.9% vs. 88.7%; p = 0.025); (3) reduced sensitivity to first-line platinum/etoposide (objective response rate: 31.6% vs. 55.1%, p = 0.015; and disease control rate; 59.7% vs. 79.6%, p = 0.027); (4) worse progression-free survival (PFS) (adjusted-HR = 1.615, p = 0.016) and overall survival (OS) (adjusted-HR = 1.640, p = 0.015) in the advanced setting. Within the advanced EP-NEC cohort, subgroups according to morphological subtype and Ki-67 index (<55% vs. ≥55%) had significantly different PFS (adjusted-p = 0.021) and OS (adjusted-p = 0.051), with the non-SC subgroup with a Ki-67 index of <55% and non-SC subgroup with a Ki-67 index of ≥55% showing the best and worst outcomes, respectively. To conclude, the morphological subtype of EP-NEC provides complementary information to the Ki-67 index and may aid identification of patients who could benefit from alternative first-line treatment strategies to platinum/etoposide.

Evaluation of Bacteria and Fungi DNA Abundance in Human Tissues

Whereas targeted and shotgun sequencing approaches are both powerful in allowing the study of tissue-associated microbiota, the human: microorganism abundance ratios in tissues of interest will ultimately determine the most suitable sequencing approach. In addition, it is possible that the knowledge of the relative abundance of bacteria and fungi during a treatment course or in pathological conditions can be relevant in many medical conditions. Here, we present a qPCR-targeted approach to determine the absolute and relative amounts of bacteria and fungi and demonstrate their relative DNA abundance in nine different human tissue types for a total of 87 samples. In these tissues, fungi genomes are more abundant in stool and skin samples but have much lower levels in other tissues. Bacteria genomes prevail in stool, skin, oral swabs, saliva, and gastric fluids. These findings were confirmed by shotgun sequencing for stool and gastric fluids. This approach may contribute to a more comprehensive view of the human microbiota in targeted studies for assessing the abundance levels of microorganisms during disease treatment/progression and to indicate the most informative methods for studying microbial composition (shotgun versus targeted sequencing) for various samples types.

Physiological and affective responses to emoji faces: Effects on facial muscle activity, skin conductance, heart rate, and self-reported affect

The objective of the present study was to evaluate emotional responses to emoji faces through physiological and self-report measures, and evaluate possible differences between men and women. One hundred participants (50 women) observed pictures of happy, neutral, and angry emoji faces, while activity of the zygomatic and corrugator muscles, skin conductance, and heart rate were measured. Self-report measures of emotional experience were also recorded. The results showed an increase in zygomatic muscle activity toward happy emoji faces. An increasing trend in corrugator muscle activity toward angry emoji faces was observed; however, this trend was only marginally significant. Happy emoji faces generated an increase in the skin conductance response. The emotional experience of the participants was also consistent with the emotions that were expressed by the emoji faces. No differences were found between sexes. Overall, the results suggest that emoji faces can especially induce pleasant affective states.

Exome and Tissue-Associated Microbiota as Predictive Markers of Response to Neoadjuvant Treatment in Locally Advanced Rectal Cancer

The clinical and pathological responses to multimodal neoadjuvant therapy in locally advanced rectal cancers (LARCs) remain unpredictable, and robust biomarkers are still lacking. Recent studies have shown that tumors present somatic molecular alterations related to better treatment response, and it is also clear that tumor-associated bacteria are modulators of chemotherapy and immunotherapy efficacy, therefore having implications for long-term survivorship and a good potential as the biomarkers of outcome. Here, we performed whole exome sequencing and 16S ribosomal RNA (rRNA) amplicon sequencing from 44 pre-treatment LARC biopsies from Argentinian and Brazilian patients, treated with neoadjuvant chemoradiotherapy or total neoadjuvant treatment, searching for predictive biomarkers of response (responders, n = 17; non-responders, n = 27). In general, the somatic landscape of LARC was not capable to predict a response; however, a significant enrichment in mutational signature SBS5 was observed in non-responders (p = 0.0021), as well as the co-occurrence of APC and FAT4 mutations (p < 0.05). Microbiota studies revealed a similar alpha and beta diversity of bacteria between response groups. Yet, the linear discriminant analysis (LDA) of effect size indicated an enrichment of Hungatella, Flavonifractor, and Methanosphaera (LDA score ≥3) in the pre-treatment biopsies of responders, while non-responders had a higher abundance of Enhydrobacter, Paraprevotella (LDA score ≥3) and Finegoldia (LDA score ≥4). Altogether, the evaluation of these biomarkers in pre-treatment biopsies could eventually predict a neoadjuvant treatment response, while in post-treatment samples, it could help in guiding non-operative treatment strategies.