ATF6 promotes colorectal cancer growth and stemness by regulating the Wnt pathway.

The unfolded protein response maintains endoplasmic reticulum (ER) homeostasis by sensing protein-folding stress and orchestrating cellular adaptation via the ER-transmembrane proteins IRE1, PERK and ATF6. Malignant cells can co-opt IRE1 and PERK to sustain growth; however, the importance of ATF6 in cancer remains poorly deciphered. We observed elevated ATF6 transcriptional activity in several cancers including colorectal carcinoma (CRC). Genetic silencing or small molecule inhibition of ATF6 blocked cell cycle progression and reduced viability of several human CRC cell lines in vitro and disrupted tumor progression in vivo. Unexpectedly, ATF6 interference disabled Wnt and Myc signaling and reduced stemness. ATF6 inhibition attenuated growth of organoids derived from malignant but not normal human intestinal tissue, decreasing Wnt-pathway activity and driving cellular differentiation. Wnt-surrogate agonism in a Wnt ligand-dependent CRC organoid restored pathway activity and rescued growth under ATF6 blockade. Our findings identify ATF6 as an unexpected facilitator of oncogenic Wnt signaling in CRC.

Multiplexed, image-based pooled screens in primary cells and tissues with PerturbView.

Optical pooled screening (OPS) is a scalable method for linking image-based phenotypes with cellular perturbations. However, it has thus far been restricted to relatively low-plex phenotypic readouts in cancer cell lines in culture due to limitations associated with in situ sequencing of perturbation barcodes. Here, we develop PerturbView, an OPS technology that leverages in vitro transcription to amplify barcodes before in situ sequencing, enabling screens with highly multiplexed phenotypic readouts across diverse systems, including primary cells and tissues. We demonstrate PerturbView in induced pluripotent stem cell-derived neurons, primary immune cells and tumor tissue sections from animal models. In a screen of immune signaling pathways in primary bone marrow-derived macrophages, PerturbView uncovered both known and novel regulators of NF-κB signaling. Furthermore, we combine PerturbView with spatial transcriptomics in tissue sections from a mouse xenograft model, paving the way to in situ screens with rich optical and transcriptomic phenotypes. PerturbView broadens the scope of OPS to a wide range of models and applications.

Índice cpod e fatores associados dos moradores de um município de pequen o porte no nordeste brasileiro / DMF index and associated factors of residents in a small municipality in Northeast Brazil / Índice CPO y factores asociados de los residentes de un pequeño municipio en el noreste de Brasil

Introdução:A atenção à Saúde Bucal no Brasil foi qualificada a partir da Política Nacional de Saúde Bucal (PNSB), através do Sistema Único de Saúde (SUS), fomentando ações de promoção, prevenção e recuperação da saúde bucal da população. A avaliação da prevalência de cárie dentária em determinada comunidade, para Estudos Epidemiológicos em Saúde Bucal, pode ser realizada por meio do índice CPOD, que fornece a quantidade média de dentes cariados, perdidos e obturados. Objetivo:O presente trabalho objetivouaferir o índice CPOD dos moradores de uma área coberta pela Equipe de Saúde Bucal (ESB) de um município de pequeno porte, caracterizar seu perfil socioeconômico, verificar seu comportamento quanto ao uso de serviços odontológicos e identificar fatores associados ao índice. Metodologia:Foi realizado um estudo de prevalência do tipo exploratório e descritivo com abordagem quantitativaem residentes de um município de pequeno porte com cobertura pela Equipe de Saúde Bucal. Foi utilizado um questionário de caracterização individual abordando identificação socioeconômica e comportamento relacionado à saúde bucal.Resultados:Na análise do CPOD, a média de dentes perdidos (5,44) foi maior que a dos dentes obturados (4,31) e cariados (1,34). Odesfecho CPOD foi associado positivamente com a idade e a necessidade do uso de prótese dentária.Conclusões:Observou-se uma média mais alta de dentes perdidos, seguida por dentes obturados, e uma média menor de dentes cariados. Verificamos que o índice CPOD individual foi mais elevado em pessoas com mais de 34 anos e naqueles que necessitavam de próteses dentárias (AU).

Introduction:Oral Health care in Brazil was qualified basedon the National Oral Health Policy (PNSB), through the Unified Health System (SUS), promoting actions to promote, prevent and recover the oral healthof the population. Assessing the prevalence of tooth decay in a community, for Epidemiological Studies inOral Health, can be conductedusing the DMFT index, which provides the average number of Decayed, Missing and Filled Teeth. Objective:Thisstudy aimed to measure the DMFT index of residents of an area covered by anOral Health Team (ESB) of a small municipality, characterize their socioeconomic profile, verify their behavior regarding the use of dental services,and identify factors associated with this index. Methodology:An exploratory and descriptive prevalence study was conductedwith a quantitative approach in residents of a small municipality covered by the Oral Health Team. An individual characterization questionnaire addressing socioeconomic identification and behavior related to oral health was used. Results:The total samplewas of 283 individuals with an average of 34 years of age. In the DMFT analysis, the average number of missing teeth (5.44) was higher than that of filled (4.31) and decayed ones(1.34). The occurrence of a DMFTindexgreater than 11 was significantly higher in individuals over 34 years of age (p value 0.000) and in subjects who needed dental prosthesis (p value 0.001). Conclusions:A higher average of missing teeth was observed, followed by filled ones, and a lower average of decayed teeth. The DMFT outcome was positively associated with age and the need to use dental prostheses (AU).

Introducción:La atención a la salud bucal en Brasil ha sido calificada por la Política Nacionalde Saúde Bucal (PNSB), a través del Sistema Único de Saúde (SUS), promoviendo acciones de promoción, prevención y recuperación de la salud bucal de la población. Para estudios epidemiológicos de salud bucal, la prevalencia de caries dental en una determinada comunidad puede ser evaluada utilizando el índice DMFT, que proporciona el número medio de dientes cariados, perdidos y obturados. Objetivo:El objetivo de este estudio fue medir el índice DMFT de los residentes de un área cubierta por el Equipo de Salud Bucal (ESB) de un pequeño municipio, caracterizar su perfil socioeconómico, verificar su comportamiento en cuanto al uso de servicios odontológicos e identificar factores asociados al índice. Metodología:Se realizó un estudio exploratorio y descriptivo de prevalencia con abordaje cuantitativo en residentes de un pequeño municipio cubierto por un Equipo de Salud Bucal. Se utilizó un cuestionario de caracterización individual que abordaba la identificación socioeconómica y el comportamiento relacionado conla salud bucodental. Resultados:La muestra total fue de 283 individuos con una edad media de 34 años. En el análisis de la DMFT, la media de dientes ausentes (5,44) fue superior a la de dientes obturados (4,31) y cariados (1,34). La incidencia de un DMFTsuperior a 11 fue significativamente mayor en los individuos de más de 34 años (valor p 0,000) y en los que necesitaban un tratamiento dental. Conclusiones:Hubo un mayor número medio de dientes ausentes, seguido de dientes obturados, y un menor número medio de dientes cariados. El resultado del DMFT se asoció positivamente con la edad y la necesidad de prótesis dentales (AU).

A dataset of new occurrence records of primates from the arc of deforestation, Brazil.

​​​​​​​The so-called arc of deforestation is a major agricultural and industrial frontier in southern Amazonia and northern Cerrado of Brazil. As arboreal mammals, the primates in this region are therefore threatened by forest loss and fragmentation. At the same time, knowledge about the taxonomic diversity and distribution ranges of these taxa is incomplete, which might hamper efficient conservation measurements. New species have been recently discovered in this region, and their ranges remain imprecise because only a few occurrence records are available for each species. Here we present 192 new records of 22 species and subspecies of Alouatta, Aotus, Ateles, Cebus, Chiropotes, Lagothrix, Leontocebus, Pithecia, Plecturocebus, Saimiri, and Sapajus, collected in 56 different localities during 10 field expeditions across the arc of deforestation between 2015 and 2018. Based on these new records, we extend the ranges of Alouatta puruensis, Ateles chamek, and Saimiri collinsi; identify potential hybridization zones between A. puruensis and A. discolor, and between At. chamek and At. marginatus; redefine the range of Plecturocebus moloch; and clarify the ranges of P. baptista and P. hoffmannsi. Moreover, these results and the dataset are valuable for further research on, for example, species distribution and habitat use modeling, for assessing species extinction risks, and for supporting efforts for the conservation of species increasingly threatened on a global deforestation frontier.

Chromosomal mapping of repetitive DNA and retroelement sequences and its implications for the chromosomal evolution process in Ctenoluciidae (Characiformes).

Ctenoluciidae is a Neotropical freshwater fish family composed of two genera, Ctenolucius (C. beani and C. hujeta) and Boulengerella (B. cuvieri, B. lateristriga, B. lucius, B. maculata, and B. xyrekes), which present diploid number conservation of 36 chromosomes and a strong association of telomeric sequences with ribosomal DNAs. In the present study, we performed chromosomal mapping of microsatellites and transposable elements (TEs) in Boulengerella species and Ctenolucius hujeta. We aim to understand how those sequences are distributed in these organisms' genomes and their influence on the chromosomal evolution of the group. Our results indicate that repetitive sequences may had an active role in the karyotypic diversification of this family, especially in the formation of chromosomal hotspots that are traceable in the diversification processes of Ctenoluciidae karyotypes. We demonstrate that (GATA)n sequences also accumulate in the secondary constriction formed by the 18 S rDNA site, which shows consistent size heteromorphism between males and females in all Boulengerella species, suggesting an initial process of sex chromosome differentiation.

Comparison of a novel rapid sampling method to serum and tonsil scraping to detect PRRSV in acutely infected sows.

Few practical methods are available to monitor the PRRSV status of the sows. Common sampling methods for sows like serum sampling, and tonsil scraping involve restraining individual sows and are labor-intensive, time-consuming, relatively invasive, and therefore, have limited use in large-scale production settings. Thus, a practical and rapid method of sampling large numbers of sows is needed. This study aimed to develop a new sampling method, named tonsil-oral scraping (TOSc) and compare TOSc to serum and tonsil scraping in terms of PRRSV qPCR detection rate and Ct values in thirty matched sows, thirty days after PRRSV outbreak. TOSc recovered a mixture of oral fluids and tonsil exudates from the sow oral cavity within seconds without restraining the animals. Results showed that, numerically, the TOSc samples had higher PRRSV qPCR detection rate (100 %) compared to serum (16.8 %) and tonsil scraping (73.1 %). Moreover, TOSc samples had lower average Ct values (29.7) than tonsil scraping (30.7) and serum (35.2). There was no significant difference in the detection rate between TOSc and tonsil scraping (Tukey test, p = 0.992), while there was a significant difference between serum and tonsil scraping (Tukey test, p < 0.001), as well as between serum and TOSc (Tukey test, p < 0.001). In terms of Ct values, there was no statistically significant difference between TOSc and tonsil scrapings (Dunn Test, p > 0.05), while there was a significant difference between tonsil scraping with serum (Dunn Test, p < 0.01), and TOSc with serum (Dunn Test, p < 0.01). Our results suggest great potential of the TOSc as a novel, practical, and rapid tool for PRRSV RNA detection in sows to assess sow herd status.

Evaluation of the effect of sample suspension concentration and viral load on the outcome of the rabies tissue culture infection test.

In this study, we examined various brain suspension concentrations and viral loads in Neuro-2a cell cultures using 20 rabies-positive bovine samples. The reproducibility of results varied: 65% showed consistent outcomes across all concentrations, while 35% disagreed in at least one. Viral titers ranged from less than 25 × 101 to 25 × 103.50 TCID50/mL, with 20% below 25 × 101 TCID50/mL. Concentrations between 5% and 20% yielded over 90% agreement in positive results, but at 30%, agreement dropped from 85% to 50%. Cell confluence was successfully maintained at 5%, 10%, and 20%, while concentrations of 30% and above led to confluence loss. Low viral loads also negatively impacted reproducibility. These results suggest that sample concentration has a direct influence on preservation of cell confluence and that low viral loads may influence the reproducibility of the rabies tissue culture infection test (RTCIT).

Potent and selective binders of the E3 ubiquitin ligase ZNRF3 stimulate Wnt signaling and intestinal organoid growth.

Selective and precise activation of signaling transduction cascades is key for cellular reprogramming and tissue regeneration. However, the development of small- or large-molecule agonists for many signaling pathways has remained elusive and is rate limiting to realize the full clinical potential of regenerative medicine. Focusing on the Wnt pathway, here we describe a series of disulfide-constrained peptides (DCPs) that promote Wnt signaling activity by modulating the cell surface levels of ZNRF3, an E3 ubiquitin ligase that controls the abundance of the Wnt receptor complex FZD/LRP at the plasma membrane. Mechanistically, monomeric DCPs induce ZNRF3 ubiquitination, leading to its cell surface clearance, ultimately resulting in FZD stabilization. Furthermore, we engineered multimeric DCPs that induce expansive growth of human intestinal organoids, revealing a dependence between valency and ZNRF3 clearance. Our work highlights a strategy for the development of potent, biologically active Wnt signaling pathway agonists via targeting of ZNRF3.

Chromosomal characterization of three species of Serrasalmini (Serrasalmidae: Characiformes).

The tribe Serrasalmini is a diverse group with paraphyletic genera and taxonomic uncertainties. Several studies have been carried out in this group of fish in order to understand this problem, including the cytogenetic approach. In this study, three species of a clade of Serrasalmini were characterized cytogenetically - Pristobrycon striolatus, Catoprion absconditus and Pygopristis denticulatus. The three species presented diploid number (2n) equal to 62 chromosomes, of one and two arms, with karyotypic formulas and species-specific fundamental numbers. Heterochromatin is centromeric and terminal (bi-telomeric) in most chromosomes, with a conspicuous interstitial block at pair 1 (m) in all three species. The nucleolar organizer regions were multiple and C-band positive, and their location was confirmed via 18S ribosomal DNA mapping; however, with additional sites. The 5S rDNA was located in interstitial region of long arm of pair 1 (m), in the three species (homeologous). Moreover, we observed synteny between 18S and 5S in the species C. absconditus and P. denticulatus, which, according to fiber-FISH, are interspersed. Thus, the maintenance of 2n (62) evidences the diversification of chromosomal formulas within the clade by non-Robertsonian rearrangements and reflects the paraphyly of the related species.

Tumor-intrinsic expression of the autophagy gene Atg16l1 suppresses anti-tumor immunity in colorectal cancer.

Microsatellite-stable colorectal cancer (MSS-CRC) is highly refractory to immunotherapy. Understanding tumor-intrinsic determinants of immunotherapy resistance is critical to improve MSS-CRC patient outcomes. Here, we demonstrate that high tumor expression of the core autophagy gene ATG16L1 is associated with poor clinical response to anti-PD-L1 therapy in KRAS-mutant tumors from IMblaze370 (NCT02788279), a large phase III clinical trial of atezolizumab (anti-PD-L1) in advanced metastatic MSS-CRC. Deletion of Atg16l1 in engineered murine colon cancer organoids inhibits tumor growth in primary (colon) and metastatic (liver and lung) niches in syngeneic female hosts, primarily due to increased sensitivity to IFN-γ-mediated immune pressure. ATG16L1 deficiency enhances programmed cell death of colon cancer organoids induced by IFN-γ and TNF, thus increasing their sensitivity to host immunity. In parallel, ATG16L1 deficiency reduces tumor stem-like populations in vivo independently of adaptive immune pressure. This work reveals autophagy as a clinically relevant mechanism of immune evasion and tumor fitness in MSS-CRC and provides a rationale for autophagy inhibition to boost immunotherapy responses in the clinic.

Ninety-day outcomes in patients diagnosed with COVID-19 in São Paulo, Brazil: a cohort study.

OBJECTIVE: COVID-19 has been associated with a significant burden to those who survive the acute phase. We aimed to describe the quality of life and symptoms of anxiety, depression, and posttraumatic stress disorder (PTSD) at 90 days after hospital discharge of COVID-19 patients. METHODS: Patients with COVID-19 admitted to a private hospital in the city of São Paulo, Brazil, between April of 2020 and April of 2021 were interviewed by telephone at 30 and 90 days after discharge to assess the quality of life and symptoms of depression, anxiety, and PTSD. RESULTS: A total of 2,138 patients were included. The mean age was 58.6 ± 15.8 years, and the median length of hospital stay was 9.0 (5.0-15.8) days. Between the two time points, depression increased from 3.1% to 7.2% (p < 0.001), anxiety increased from 3.2% to 6.2% (p < 0.001), and PTSD increased from 2.3% to 5.0% (p < 0.001). At least one physical symptom related to COVID-19 diagnosis persisted in 32% of patients at day 90. CONCLUSIONS: Persistence of physical symptoms was high even at 90 days after discharge. Although the prevalence of symptoms of anxiety, depression, and PTSD was low, these symptoms persisted for three months, with a significant increase between the time points. This finding indicates the need to identify at-risk patients so that they can be given an appropriate referral at discharge.

A New Assessment of Robust Capuchin Monkey (Sapajus) Evolutionary History Using Genome-Wide SNP Marker Data and a Bayesian Approach to Species Delimitation.

Robust capuchin monkeys, Sapajus genus, are among the most phenotypically diverse and widespread groups of primates in South America, with one of the most confusing and often shifting taxonomies. We used a ddRADseq approach to generate genome-wide SNP markers for 171 individuals from all putative extant species of Sapajus to access their evolutionary history. Using maximum likelihood, multispecies coalescent phylogenetic inference, and a Bayes Factor method to test for alternative hypotheses of species delimitation, we inferred the phylogenetic history of the Sapajus radiation, evaluating the number of discrete species supported. Our results support the recognition of three species from the Atlantic Forest south of the São Francisco River, with these species being the first splits in the robust capuchin radiation. Our results were congruent in recovering the Pantanal and Amazonian Sapajus as structured into three monophyletic clades, though new morphological assessments are necessary, as the Amazonian clades do not agree with previous morphology-based taxonomic distributions. Phylogenetic reconstructions for Sapajus occurring in the Cerrado, Caatinga, and northeastern Atlantic Forest were less congruent with morphology-based phylogenetic reconstructions, as the bearded capuchin was recovered as a paraphyletic clade, with samples from the Caatinga biome being either a monophyletic clade or nested with the blond capuchin monkey.

Synthetic Multivalent Disulfide-Constrained Peptide Agonists Potentiate Wnt1/ß-Catenin Signaling via LRP6 Coreceptor Clustering.

Wnt ligands are critical for tissue homeostasis and form a complex with LRP6 and frizzled coreceptors to initiate Wnt/ß-catenin signaling. Yet, how different Wnts achieve various levels of signaling activation through distinct domains on LRP6 remains elusive. Developing tool ligands that target individual LRP6 domains could help elucidate the mechanism of Wnt signaling regulation and uncover pharmacological approaches for pathway modulation. We employed directed evolution of a disulfide constrained peptide (DCP) to identify molecules that bind to the third ß-propeller domain of LRP6. The DCPs antagonize Wnt3a while sparing Wnt1 signaling. Using PEG linkers with different geometries, we converted the Wnt3a antagonist DCPs to multivalent molecules that potentiated Wnt1 signaling by clustering the LRP6 coreceptor. The mechanism of potentiation is unique as it occurred only in the presence of extracellular secreted Wnt1 ligand. While all DCPs recognized a similar binding interface on LRP6, they displayed different spatial orientations that influenced their cellular activities. Moreover, structural analyses revealed that the DCPs exhibited new folds that were distinct from the parent DCP framework they were evolved from. The multivalent ligand design principles highlighted in this study provide a path for developing peptide agonists that modulate different branches of cellular Wnt signaling.

Tão humano quanto você: processos de exclusão das pessoas em situação de rua no Rio de Janeiro / As human as you: processes of exclusion of the homeless population in Rio de Janeiro

Utilizando o Rio de Janeiro como cenário de disparidades sociais, e com base em reflexões acerca do direito à cidade e o pressuposto de humanidade, o presente ensaio busca ecoar as vozes de pessoas em situação de rua nas suas vivências como os "outros" da cidade. A partir da análise de cartas elaboradas pela população de rua para os residentes em seu entorno, nas atividades de rodas de conversa do Projeto RUAS em 2019, percebe-se que os processos higienistas e de exclusão camuflam um debate mais pungente, do que (e de quem) é considerado humano em nossa sociedade. E a população em situação de rua está atenta a isso, no momento em que reforça uma série de reivindicações que clamam pela dignidade de um tratamento humano na cidade.

Ninety-day outcomes in patients diagnosed with COVID-19 in São Paulo, Brazil: a cohort study / Desfechos em 90 dias entre pacientes com diagnóstico de COVID-19 em São Paulo (SP): estudo de coorte

ABSTRACT Objective: COVID-19 has been associated with a significant burden to those who survive the acute phase. We aimed to describe the quality of life and symptoms of anxiety, depression, and posttraumatic stress disorder (PTSD) at 90 days after hospital discharge of COVID-19 patients. Methods: Patients with COVID-19 admitted to a private hospital in the city of São Paulo, Brazil, between April of 2020 and April of 2021 were interviewed by telephone at 30 and 90 days after discharge to assess the quality of life and symptoms of depression, anxiety, and PTSD. Results: A total of 2,138 patients were included. The mean age was 58.6 ± 15.8 years, and the median length of hospital stay was 9.0 (5.0-15.8) days. Between the two time points, depression increased from 3.1% to 7.2% (p < 0.001), anxiety increased from 3.2% to 6.2% (p < 0.001), and PTSD increased from 2.3% to 5.0% (p < 0.001). At least one physical symptom related to COVID-19 diagnosis persisted in 32% of patients at day 90. Conclusions: Persistence of physical symptoms was high even at 90 days after discharge. Although the prevalence of symptoms of anxiety, depression, and PTSD was low, these symptoms persisted for three months, with a significant increase between the time points. This finding indicates the need to identify at-risk patients so that they can be given an appropriate referral at discharge.

RESUMO Objetivo: A COVID-19 tem sido associada a um fardo significativo para aqueles que sobrevivem à fase aguda. Nosso objetivo foi descrever a qualidade de vida e sintomas de ansiedade, depressão e transtorno de estresse pós-traumático (TEPT) 90 dias após a alta hospitalar em pacientes com COVID-19. Métodos: Pacientes com COVID-19 internados em um hospital privado na cidade de São Paulo (SP) entre abril de 2020 e abril de 2021 foram entrevistados por telefone 30 e 90 dias após a alta para avaliar a qualidade de vida e sintomas de depressão, ansiedade e TEPT. Resultados: Foram incluídos 2.138 pacientes. A média de idade foi de 58,6 ± 15,8 anos, e a mediana do tempo de internação hospitalar foi de 9,0 (5,0-15,8) dias. Entre os dois momentos, a depressão aumentou de 3,1% para 7,2% (p < 0,001), a ansiedade, de 3,2% para 6,2% (p < 0,001), e o TEPT, de 2,3% para 5,0% (p < 0,001). Pelo menos um sintoma físico relacionado ao diagnóstico de COVID-19 persistia em 32% dos pacientes no 90º dia. Conclusões: A persistência dos sintomas físicos foi elevada mesmo 90 dias após a alta. Embora a prevalência de sintomas de ansiedade, depressão e TEPT tenha sido baixa, esses sintomas persistiram por três meses, com aumento significativo entre os momentos. Esse achado indica a necessidade de identificar os pacientes de risco para que possam receber o encaminhamento adequado no momento da alta.

Directed evolution identifies high-affinity cystine-knot peptide agonists and antagonists of Wnt/ß-catenin signaling.

Developing peptide-based tools to fine-tune growth signaling pathways, in particular molecules with exquisite selectivity and high affinities, opens up opportunities for cellular reprogramming in tissue regeneration. Here, we present a library based on cystine-knot peptides (CKPs) that incorporate multiple loops for randomization and selection via directed evolution. Resulting binders could be assembled into multimeric structures to fine-tune cellular signaling. An example is presented for the Wnt pathway, which plays a key role in the homeostasis and regeneration of tissues such as lung, skin, and intestine. We discovered picomolar affinity CKP agonists of the human LPR6 receptor by exploring the limits of the topological manipulation of LRP6 dimerization. Structural analyses revealed that the agonists bind at the first ß-propeller domain of LRP6, mimicking the natural Wnt inhibitors DKK1 and SOST. However, the CKP agonists exhibit a different mode of action as they amplify the signaling of natural Wnt ligands but do not activate the pathway by themselves. In an alveolosphere organoid model, the CKP agonists induced alveolar stem cell activity. They also stimulated growth in primary human intestinal organoids. The approach described here advances the important frontier of next-generation agonist design and could be applied to other signaling pathways to discover tunable agonist ligands.

ARID1A mutations confer intrinsic and acquired resistance to cetuximab treatment in colorectal cancer.

Most colorectal (CRC) tumors are dependent on EGFR/KRAS/BRAF/MAPK signaling activation. ARID1A is an epigenetic regulator mutated in approximately 5% of non-hypermutated CRC tumors. Here we show that anti-EGFR but not anti-VEGF treatment enriches for emerging ARID1A mutations in CRC patients. In addition, we find that patients with ARID1A mutations, at baseline, are associated with worse outcome when treated with cetuximab- but not bevacizumab-containing therapies; thus, this suggests that ARID1A mutations may provide both an acquired and intrinsic mechanism of resistance to anti-EGFR therapies. We find that, ARID1A and EGFR-pathway genetic alterations are mutually exclusive across lung and colorectal cancers, further supporting a functional connection between these pathways. Our results not only suggest that ARID1A could be potentially used as a predictive biomarker for cetuximab treatment decisions but also provide a rationale for exploring therapeutic MAPK inhibition in an unexpected but genetically defined segment of CRC patients.

Antibody targeting of E3 ubiquitin ligases for receptor degradation.

Most current therapies that target plasma membrane receptors function by antagonizing ligand binding or enzymatic activities. However, typical mammalian proteins comprise multiple domains that execute discrete but coordinated activities. Thus, inhibition of one domain often incompletely suppresses the function of a protein. Indeed, targeted protein degradation technologies, including proteolysis-targeting chimeras1 (PROTACs), have highlighted clinically important advantages of target degradation over inhibition2. However, the generation of heterobifunctional compounds binding to two targets with high affinity is complex, particularly when oral bioavailability is required3. Here we describe the development of proteolysis-targeting antibodies (PROTABs) that tether cell-surface E3 ubiquitin ligases to transmembrane proteins, resulting in target degradation both in vitro and in vivo. Focusing on zinc- and ring finger 3 (ZNRF3), a Wnt-responsive ligase, we show that this approach can enable colorectal cancer-specific degradation. Notably, by examining a matrix of additional cell-surface E3 ubiquitin ligases and transmembrane receptors, we demonstrate that this technology is amendable for 'on-demand' degradation. Furthermore, we offer insights on the ground rules governing target degradation by engineering optimized antibody formats. In summary, this work describes a strategy for the rapid development of potent, bioavailable and tissue-selective degraders of cell-surface proteins.

Phylogenetics and an updated taxonomic status of the Tamarins (Callitrichinae, Cebidae).

Traditionally, Saguinus has been organized into six taxonomic groups: bicolor, inustus, midas, mystax, nigricollis, and oedipus. After recent revisions, taxonomic reclassifications were proposed, including (1) the recognition of Leontocebus as a new genus, and (2) the subdivision of Saguinus into three subgenera. Nonetheless, the contradictory nature of these results reinforces the inconsistency concerning the monophyletic status of tamarins and its interspecific phylogeny. Therefore, in this study, we carried out phylogenetic inferences of Saguinus based on 44 molecular markers, of which 37 were from nuclear DNA and seven from mitochondrial DNA. A final dataset of 24,202 base pairs (bp) was obtained from 60 specimens of all recognized species of Saguinus and, also representatives of two main lineages of Leontocebus. Phylogenetic hypothesis was obtained from Maximum Likelihood (ML) and Bayesian inference (BI) methods. We also construct a Species Tree and a fossil-calibrated multi-locus phylogeny to estimate the time of divergence of Tamarins. Our phylogenetic results validated Leontocebus, or nigricollis group, as monophyletic, and recovered additionally three main clades within Saguinus. Same topology was obtained by the Species Tree. These clades correspond to (1) inustus + mystax groups, (2) oedipus group and (3) bicolor + midas group. Our results show support for a 10.5-million-year-old split between Leontocebus and the remaining Saguinus, followed by two other cladogenetic events, around 9.3 and 7.2 mya, which lead to the rise of the main clades of Saguinus. These phylogenetic data, in concert with the consistent morphological, ecological behavior and biogeographic evidence suggest a new classification for the Amazonian and trans-Andean tamarins. Therefore, we support the validation of Leontocebus as genus and recommend the split of Saguinus into three genera: (1) Tamarinus (inustus and mystax groups), (2) Oedipomidas (oedipus group), and (3) Saguinus (bicolor and midas groups).