RESUMO
We present the complete closed circular genome sequence derived from Oxford Nanopore sequencing of the shipworm endosymbiont Teredinibacter turnerae T7902 (DSM 15152, ATCC 39867), originally isolated from the shipworm Lyrodus pedicellatus (1). This sequence will aid in the comparative genomics of shipworm endosymbionts and the understanding of host-symbiont evolution.
RESUMO
Acquired resistance remains a major challenge for therapies targeting oncogene activated pathways. KRAS is the most frequently mutated oncogene in human cancers, yet strategies targeting its downstream signaling kinases have failed to produce durable treatment responses. Here, we developed multiple models of acquired resistance to dual-mechanism ERK/MAPK inhibitors across KRAS-mutant pancreatic, colorectal, and lung cancers, and then probed the long-term events enabling survival against this class of drugs. These studies revealed that resistance emerges secondary to large-scale transcriptional adaptations that are diverse and cell line-specific. Transcriptional reprogramming extends beyond the well-established early response, and instead represents a dynamic, evolved process that is refined to attain a stably resistant phenotype. Mechanistic and translational studies reveal that resistance to dual-mechanism ERK/MAPK inhibition is broadly susceptible to manipulation of the epigenetic machinery, and that Mediator kinase, in particular, can be co-targeted at a bottleneck point to prevent diverse, cell line-specific resistance programs.
RESUMO
Teredinibacter turnerae is a cultivable cellulolytic Gammaproeteobacterium (Cellvibrionaceae) that commonly occurs as an intracellular endosymbiont in the gills of wood-eating bivalves of the family Teredinidae (shipworms). The genome of T. turnerae encodes a broad range of enzymes that deconstruct cellulose, hemicellulose, and pectin and contribute to lignocellulose digestion in the shipworm gut. However, the mechanism by which symbiont-made enzymes are secreted by T. turnerae and subsequently transported to the site of lignocellulose digestion in the shipworm gut is incompletely understood. Here, we show that T. turnerae cultures grown on carboxymethyl cellulose (CMC) produce outer membrane vesicles (OMVs) that contain a variety of proteins identified by LC-MS/MS as carbohydrate-active enzymes with predicted activities against cellulose, hemicellulose, and pectin. Reducing sugar assays and zymography confirm that these OMVs retain cellulolytic activity, as evidenced by hydrolysis of CMC. Additionally, these OMVs were enriched with TonB-dependent receptors, which are essential to carbohydrate and iron acquisition by free-living bacteria. These observations suggest potential roles for OMVs in lignocellulose utilization by T. turnerae in the free-living state, in enzyme transport and host interaction during symbiotic association, and in commercial applications such as lignocellulosic biomass conversion.
RESUMO
The cranial sutures are proposed to be a stem cell niche, harbouring skeletal stem cells that are directly involved in development, homeostasis and healing. Like the craniofacial bones, the sutures are formed from both mesoderm and neural crest. During cranial bone repair, neural crest cells have been proposed to be key players; however, neural crest contributions to adult sutures are not well defined, and the relative importance of suture proximity is unclear. Here, we use genetic approaches to re-examine the neural crest-mesoderm boundaries in the adult mouse skull. These are combined with calvarial wounding experiments suggesting that suture proximity improves the efficiency of cranial repair. Furthermore, we demonstrate that Gli1+ and Axin2+ skeletal stem cells are present in all calvarial sutures examined. We propose that the position of the defect determines the availability of neural crest-derived progenitors, which appear to be a key element in the repair of calvarial defects.
Assuntos
Suturas Cranianas , Crânio , Camundongos , Animais , Células-Tronco , Crista Neural , MesodermaRESUMO
OBJECTIVE: To create a blueprint for surgical department leaders, academic institutions, and funding agencies to optimally support surgeon-scientists. BACKGROUND: Scientific contributions by surgeons have been transformative across many medical disciplines. Surgeon-scientists provide a distinct approach and mindset toward key scientific questions. However, lack of institutional support, pressure for increased clinical productivity, and growing administrative burden are major challenges for the surgeon-scientist, as is the time-consuming nature of surgical training and practice. METHODS: An American Surgical Association Research Sustainability Task Force was created to outline a blueprint for sustainable science in surgery. Leaders from top NIH-sponsored departments of surgery engaged in video and in-person meetings between January and April 2023. A strength, weakness, opportunities, threats analysis was performed, and workgroups focused on the roles of surgeons, the department and institutions, and funding agencies. RESULTS: Taskforce recommendations: (1) SURGEONS: Growth mindset : identifying research focus, long-term planning, patience/tenacity, team science, collaborations with disparate experts; Skill set : align skills and research, fill critical skill gaps, develop team leadership skills; DEPARTMENT OF SURGERY (DOS): (2) MENTORSHIP: Chair : mentor-mentee matching/regular meetings/accountability, review of junior faculty progress, mentorship training requirement, recognition of mentorship (eg, relative value unit equivalent, awards; Mentor: dedicated time, relevant scientific expertise, extramural funding, experience and/or trained as mentor, trusted advisor; Mentee : enthusiastic/eager, proactive, open to feedback, clear about goals; (3) FINANCIAL SUSTAINABILITY: diversification of research portfolio, identification of matching funding sources, departmental resource awards (eg, T-/P-grants), leveraging of institutional resources, negotiation of formalized/formulaic funds flow investment from academic medical center toward science, philanthropy; (4) STRUCTURAL/STRATEGIC SUPPORT: Structural: grants administrative support, biostats/bioinformatics support, clinical trial and research support, regulatory support, shared departmental laboratory space/equipment; Strategic: hiring diverse surgeon-scientist/scientists faculty across DOS, strategic faculty retention/ recruitment, philanthropy, career development support, progress tracking, grant writing support, DOS-wide research meetings, regular DOS strategic research planning; (5) COMMUNITY AND CULTURE: Community: right mix of faculty, connection surgeon with broad scientific community; Culture: building research infrastructure, financial support for research, projecting importance of research (awards, grand rounds, shoutouts); (6) THE ROLE OF INSTITUTIONS: Foundation: research space co-location, flexible start-up packages, courses/mock study section, awards, diverse institutional mentorship teams; Nurture: institutional infrastructure, funding (eg, endowed chairs), promotion friendly toward surgeon-scientists, surgeon-scientists in institutional leadership positions; Expectations: RVU target relief, salary gap funding, competitive starting salaries, longitudinal salary strategy; (7) THE ROLE OF FUNDING AGENCIES: change surgeon research training paradigm, offer alternate awards to K-awards, increasing salary cap to reflect market reality, time extension for surgeon early-stage investigator status, surgeon representation on study section, focused award strategies for professional societies/foundations. CONCLUSIONS: Authentic recommitment from surgeon leaders with intentional and ambitious actions from institutions, corporations, funders, and society is essential in order to reap the essential benefits of surgeon-scientists toward advancements of science.
Assuntos
Pesquisa Biomédica , Cirurgiões , Humanos , Estados Unidos , Mentores , Docentes , Centros Médicos Acadêmicos , Mobilidade Ocupacional , National Institutes of Health (U.S.)RESUMO
The pore-forming S. aureus α-toxin (Hla) contributes to virulence and disease pathogenesis. While high concentrations of toxin induce cell death, neutrophils exhibit relative resistance to lysis, suggesting that the action of Hla may not be solely conferred by lytic susceptibility. Using intravital microscopy, we observed that Hla disrupts neutrophil localization and clustering early in infection. Hla forms a narrow, ion-selective pore, suggesting that Hla may dysregulate calcium or other ions to impair neutrophil function. We found that sub-lytic Hla did not permit calcium influx but caused rapid membrane depolarization. Depolarization decreases the electrogenic driving force for calcium, and concordantly, Hla suppressed calcium signaling in vitro and in vivo and calcium-dependent leukotriene B4 (LTB4) production, a key mediator of neutrophil clustering. Thus, Hla disrupts the early patterning of the neutrophil response to infection, in part through direct impairment of neutrophil calcium signaling. This early mis-localization of neutrophils may contribute to establishment of infection.
Assuntos
Neutrófilos , Staphylococcus aureus , Neutrófilos/metabolismo , Staphylococcus aureus/metabolismo , Cálcio/metabolismo , Sinalização do CálcioRESUMO
Enhancers possess both structural elements mediating promoter looping and functional elements mediating gene expression. Traditional models of enhancer-mediated gene regulation imply genomic overlap or immediate adjacency of these elements. We test this model by combining densely-tiled CRISPRa screening with nucleosome-resolution Region Capture Micro-C topology analysis. Using this integrated approach, we comprehensively define the cis-regulatory landscape for the tumor suppressor PTEN, identifying and validating 10 distinct enhancers and defining their 3D spatial organization. Unexpectedly, we identify several long-range functional enhancers whose promoter proximity is facilitated by chromatin loop anchors several kilobases away, and demonstrate that accounting for this spatial separation improves the computational prediction of validated enhancers. Thus, we propose a new model of enhancer organization incorporating spatial separation of essential functional and structural components.
RESUMO
Evidence has long suggested that epidermal growth factor receptor (EGFR) may play a prominent role in triple-negative breast cancer (TNBC) pathogenesis, but clinical trials of EGFR inhibitors have yielded disappointing results. Using a candidate drug screen, we identified that inhibition of cyclin-dependent kinases 12 and 13 (CDK12/13) dramatically sensitizes diverse models of TNBC to EGFR blockade. This combination therapy drives cell death through the 4E-BP1-dependent suppression of the translation and translation-linked turnover of driver oncoproteins, including MYC. A genome-wide CRISPR/Cas9 screen identified the CCR4-NOT complex as a major determinant of sensitivity to the combination therapy whose loss renders 4E-BP1 unresponsive to drug-induced dephosphorylation, thereby rescuing MYC translational suppression and promoting MYC stability. The central roles of CCR4-NOT and 4E-BP1 in response to the combination therapy were further underscored by the observation of CNOT1 loss and rescue of 4E-BP1 phosphorylation in TNBC cells that naturally evolved therapy resistance. Thus, pharmacological inhibition of CDK12/13 reveals a long-proposed EGFR dependence in TNBC that functions through the cooperative regulation of translation-coupled oncoprotein stability.
Assuntos
Neoplasias de Mama Triplo Negativas , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Receptores ErbB/genética , Fosforilação , Morte Celular , Proteínas Oncogênicas , Quinases Ciclina-Dependentes/genética , Fatores de TranscriçãoRESUMO
BACKGROUND: Resection remains the cornerstone of curative-intent treatment for biliary tract cancers (BTCs). However, recent randomized data also support a role for adjuvant chemotherapy (AC). This study aimed to characterize trends in the use of AC and subsequent outcomes in gallbladder cancer and cholangiocarcinoma (CCA). METHODS: The National Cancer Database (NCDB) was queried for patients with resected, localized BTC from 2010 to 2018. Trends in AC were compared among BTC subtypes and stages of disease. Multivariable logistic regression was used to identify factors associated with receipt of AC. Survival analysis was performed with Kaplan-Meier and multivariable Cox proportional hazards methods. RESULTS: The study identified 7039 patients: 4657 (66%) with gallbladder cancer, 1159 (17%) with intrahepatic CCA (iCCA), and 1223 (17%) with extrahepatic CCA (eCCA). Adjuvant chemotherapy was administered to 2172 (31%) patients, increasing from 23% in 2010 to 41% in 2018. Factors associated with AC included female sex, year of diagnosis, private insurance, care at an academic center, higher education, eCCA (vs iCCA), positive margins, and stage II or III disease (vs stage I). Alternatively, increasing age, higher comorbidity score, gallbladder cancer (vs iCCA), and farther travel distance for treatment were associated with reduced odds of AC. Overall, AC was not associated with a survival advantage. However, subgroup analysis showed that AC was associated with a significant reduction in mortality among patients with eCCA. CONCLUSIONS: Among the patients with resected BTC, those who received AC were in the minority. In the context of recent randomized data and evolving recommendations, emphasis on guideline concordance with a focus on at-risk populations may improve outcomes.
Assuntos
Neoplasias dos Ductos Biliares , Neoplasias do Sistema Biliar , Colangiocarcinoma , Neoplasias da Vesícula Biliar , Humanos , Feminino , Neoplasias da Vesícula Biliar/tratamento farmacológico , Neoplasias da Vesícula Biliar/cirurgia , Neoplasias da Vesícula Biliar/patologia , Neoplasias do Sistema Biliar/tratamento farmacológico , Neoplasias do Sistema Biliar/cirurgia , Neoplasias do Sistema Biliar/patologia , Colangiocarcinoma/patologia , Quimioterapia Adjuvante , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologiaRESUMO
Maintaining independence is the top health-related priority reported by older patients with advanced kidney disease.1 Unfortunately, functional losses such as fatigue, skeletal muscle loss, infection, cognitive decline, and diminished aerobic capacity are very common among patients receiving hemodialysis for chronic kidney failure. Such functional losses are associated with higher mortality2-4 and affect patients' physical activity level and overall quality of life. Indeed, symptom burden and mortality in patients receiving hemodialysis rival those in patients with cancer.5 Nephrology societies, clinicians, and above all patients and families are therefore interested in preserving quality of life and function for patients on dialysis.
Assuntos
Falência Renal Crônica , Diálise Renal , Humanos , Antídotos , Qualidade de Vida , Exercício FísicoRESUMO
Listeria monocytogenes (Lm) is a food-borne pathogen that causes severe bacterial gastroenteritis, with high rates of hospitalization and mortality. Lm is ubiquitous in soil, water and livestock, and can survive and proliferate at low temperatures. Following oral ingestion of contaminated food, Lm crosses the epithelium through intestinal goblet cells in a mechanism mediated by Lm InlA binding host E-cadherin. Importantly, human infections typically occur with Lm growing at or below room temperature, which is flagellated and motile. Even though many important human bacterial pathogens are flagellated, little is known regarding the effect of Lm motility on invasion and immune evasion. Here, we used complementary imaging and computer modeling approaches to test the hypothesis that bacterial motility helps Lm locate and engage target cells permissive for invasion. Imaging explanted mouse and human intestine, we showed that Lm grown at room temperature uses motility to scan the epithelial surface and preferentially attach to target cells. Furthermore, we integrated quantitative parameters from our imaging experiments to construct a versatile "layered" cellular Potts model (L-CPM) that simulates host-pathogen dynamics. Simulated data are consistent with the hypothesis that bacterial motility enhances invasion by allowing bacteria to search the epithelial surface for their preferred invasion targets. Indeed, our model consistently predicts that motile bacteria invade twice as efficiently over the first hour of infection. We also examined how bacterial motility affected interactions with host cellular immunity. In a mouse model of persistent infection, we found that neutrophils migrated to the apical surface of the epithelium 5 hours post infection and interacted with Lm. Yet in contrast to the view that neutrophils "hunt" for bacteria, we found that these interactions were driven by motility of Lm-which moved at least ~50x faster than neutrophils. Furthermore, our L-CPM predicts that motile bacteria maintain their invasion advantage even in the presence of host phagocytes, with the balance between invasion and phagocytosis governed almost entirely by bacterial motility. In conclusion, our simulations provide insight into host pathogen interaction dynamics at the intestinal epithelial barrier early during infection.
Assuntos
Enteropatias , Listeria monocytogenes , Listeria , Listeriose , Camundongos , Animais , Humanos , Proteínas de Bactérias/metabolismo , Intestinos/microbiologiaRESUMO
Intrahepatic cholangiocarcinoma (ICC) remains a deadly malignancy lacking systemic therapies for advanced disease. Recent advancements include selective FGFR1-3 inhibitors for the 15% of ICC patients harboring fusions, although survival is limited by poor response and resistance. Herein we report generation of a patient-derived FGFR2 fusion-positive ICC model system consisting of a cell line, organoid, and xenograft, which have undergone complete histologic, genomic, and phenotypic characterization, including testing standard-of-care systemic therapies. Using these FGFR2 fusion-positive ICC models, we conducted an unbiased high-throughput small molecule screen to prioritize combination strategies with FGFR inhibition, from which HDAC inhibition together with pemigatinib was validated in vitro and in vivo as a synergistic therapy for ICC. Additionally, we demonstrate broad utility of the FGFR/HDAC combination for other FGFR fusion-positive solid tumors. These data are directly translatable and justify early phase trials to establish dosing, safety, and therapeutic efficacy of this synergistic combination.
RESUMO
BACKGROUND: Sclerotherapy is commonly performed for elimination of reticular and telangiectatic leg veins. There are several variations in practice, from the preparation to post-therapy directives. OBJECTIVE: To critically examine the misconceptions of sclerotherapy for aesthetic indications. MATERIALS AND METHODS: This review assesses evidence for and against each of the most common myths regarding sclerotherapy for aesthetic indications. RESULTS: Sclerotherapy can be safely used to treat veins in areas other than the lower extremities, with the exception of the face. Laser therapy is not superior to sclerotherapy for the treatment of small telangiectatic veins on the lower extremities. The type of syringe used to produce foam sclerotherapy is an important procedural consideration. After sclerotherapy, graduated compression stocking usage is a vital part of the procedure. Detergent sclerotherapy agents are similar, but not equivalent. Touch-up treatments after sclerotherapy should not be performed for 2 months post-treatment. Foam sclerotherapy does not have a high risk for air emboli. It is not advisable to treat the leg veins in "sections." Finally, one cannot reliably treat the telangiectatic veins without treating the feeding reticular veins for a satisfactory result. CONCLUSION: Many aspects of sclerotherapy have existing evidence to dictate best clinical practice.
Assuntos
Telangiectasia , Varizes , Estética , Humanos , Soluções Esclerosantes/efeitos adversos , Escleroterapia/efeitos adversos , Escleroterapia/métodos , Telangiectasia/terapia , Resultado do Tratamento , Varizes/tratamento farmacológicoRESUMO
Mutationally activated BRAF is detected in approximately 7% of human lung adenocarcinomas, with BRAFT1799A serving as a predictive biomarker for treatment of patients with FDA-approved inhibitors of BRAFV600E oncoprotein signaling. In genetically engineered mouse (GEM) models, expression of BRAFV600E in the lung epithelium initiates growth of benign lung tumors that, without additional genetic alterations, rarely progress to malignant lung adenocarcinoma. To identify genes that cooperate with BRAFV600E for malignant progression, we used Sleeping Beauty-mediated transposon mutagenesis, which dramatically accelerated the emergence of lethal lung cancers. Among the genes identified was Rbms3, which encodes an RNA-binding protein previously implicated as a putative tumor suppressor. Silencing of RBMS3 via CRISPR/Cas9 gene editing promoted growth of BRAFV600E lung organoids and promoted development of malignant lung cancers with a distinct micropapillary architecture in BRAFV600E and EGFRL858R GEM models. BRAFV600E/RBMS3Null lung tumors displayed elevated expression of Ctnnb1, Ccnd1, Axin2, Lgr5, and c-Myc mRNAs, suggesting that RBMS3 silencing elevates signaling through the WNT/ß-catenin signaling axis. Although RBMS3 silencing rendered BRAFV600E-driven lung tumors resistant to the effects of dabrafenib plus trametinib, the tumors were sensitive to inhibition of porcupine, an acyltransferase of WNT ligands necessary for their secretion. Analysis of The Cancer Genome Atlas patient samples revealed that chromosome 3p24, which encompasses RBMS3, is frequently lost in non-small cell lung cancer and correlates with poor prognosis. Collectively, these data reveal the role of RBMS3 as a lung cancer suppressor and suggest that RBMS3 silencing may contribute to malignant NSCLC progression. SIGNIFICANCE: Loss of RBMS3 cooperates with BRAFV600E to induce lung tumorigenesis, providing a deeper understanding of the molecular mechanisms underlying mutant BRAF-driven lung cancer and potential strategies to more effectively target this disease.
Assuntos
Adenocarcinoma de Pulmão , Carcinogênese , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Proteínas Proto-Oncogênicas B-raf , Proteínas de Ligação a RNA , Transativadores , Animais , Humanos , Camundongos , Adenocarcinoma de Pulmão/genética , Carcinoma Pulmonar de Células não Pequenas/genética , Proliferação de Células , Pulmão/patologia , Neoplasias Pulmonares/genética , Mutagênese , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas de Ligação a RNA/genética , Transativadores/metabolismo , Via de Sinalização Wnt , Carcinogênese/genéticaRESUMO
BACKGROUND: Optimal management of stage II/III gastric cancer requires multidisciplinary care, often necessitating treatment at more than one facility. We aimed to determine patterns of "fragmented" care and its impact on outcomes, including concordance with National Comprehensive Cancer Network (NCCN) guidelines and overall survival. METHODS: The 2006-2016 National Cancer Database was queried for patients with clinical stage II/III gastric adenocarcinoma who received preoperative therapy in addition to surgery. Patients were stratified based on whether surgery and chemotherapy/chemoradiation were performed at one versus multiple facilities (termed "coordinated" and "fragmented" care, respectively). Multivariable logistic regression was performed to identify factors associated with fragmented care. Survival was compared using Kaplan-Meier and Cox proportional hazards methods. RESULTS: Overall, 2033 patients met study criteria: 1043 (51.3%) received coordinated care and 990 (48.7%) fragmented care. There was no significant difference in time to surgery or pathologic upstaging by care structure. On adjusted analysis, factors associated with receipt of fragmented care included increasing age and distance traveled to the treating facility. Factors associated with coordinated care included metropolitan residence and treatment at academic and high-volume centers. Fragmented care was associated with a reduction in guideline-preferred perioperative chemotherapy (odds ratio [OR] 0.78, 95% confidence interval [CI] 0.63-0.97, p = 0.02) and increased mortality (HR 1.16, 95% CI 1.00-1.34, p = 0.05). CONCLUSIONS: For patients with stage II/III gastric cancer, fragmented care is associated with inferior outcomes, including a reduction in preferred perioperative treatment and survival. Further work is needed to ensure equitable outcomes among patients as complex cancer care becomes more regionalized.
Assuntos
Neoplasias Gástricas , Neoplasias Testiculares , Quimiorradioterapia/métodos , Humanos , Masculino , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Neoplasias Gástricas/patologiaRESUMO
Achieving selectivity across the human kinome is a major hurdle in kinase inhibitor drug discovery. Assays using active, phosphorylated protein kinases bias hits toward poorly selective inhibitors that bind within the highly conserved adenosine triphosphate (ATP) pocket. Targeting inactive (vs active) kinase conformations offers advantages in achieving selectivity because of their more diversified structures. Kinase cascade assays are typically initiated with target kinases in their unphosphorylated inactive forms, which are activated during the assays. Therefore, these assays are capable of identifying inhibitors that preferentially bind to the unphosphorylated form of the enzyme in addition to those that bind to the active form. We applied this cascade assay to the emerging cancer immunotherapy target hematopoietic progenitor kinase 1 (HPK1), a serine/threonine kinase that negatively regulates T cell receptor signaling. Using this approach, we discovered an allosteric, inactive conformation-selective triazolopyrimidinone HPK1 inhibitor, compound 1. Compound 1 binds to unphosphorylated HPK1 >24-fold more potently than active HPK1, is not competitive with ATP, and is highly selective against kinases critical for T cell signaling. Furthermore, compound 1 does not bind to the isolated HPK1 kinase domain alone but requires other domains. Together, these data indicate that 1 is an allosteric HPK1 inhibitor that attenuates kinase autophosphorylation by binding to a pocket consisting of residues within and outside of the kinase domain. Our study demonstrates that cascade assays can lead to the discovery of highly selective kinase inhibitors. The triazolopyrimidinone described in this study may represent a privileged chemical scaffold for further development of potent and selective HPK1 inhibitors.
Assuntos
Inibidores de Proteínas Quinases/química , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Pirimidinonas/química , Triazóis/química , Proteínas Adaptadoras de Transdução de Sinal/química , Ensaios de Triagem em Larga Escala , Humanos , Fosfoproteínas/química , Fosforilação , Proteínas Serina-Treonina Quinases/químicaRESUMO
BACKGROUND: Despite numerous options for nasal ala reconstruction, advantages and disadvantages of each method are unclear. OBJECTIVE: To summarize reported outcomes of local flaps without the use of grafts for nasal ala oncologic reconstructive surgery. METHODS: A nasal ala-specific protocol was adapted from a previous head- and neck-specific PROSPERO submission (CRD42017071596). The search was conducted in MEDLINE, EMBASE, and CENTRAL on December 23, 2017 and updated on May 10, 2019. Two reviewers screened 9,313 results from head and neck literature. Study bias was evaluated with the ROBINS-I tool. RESULTS: Subunit-based categorization of included studies identified 12 nasal ala-specific publications. Complications (flap necrosis, hematoma, wound infections, trapdoor deformities, and dehiscence), functional (nasal valve or respiratory dysfunction), and cosmetic (alar rim distortion/asymmetry/notching, secondary/revisionary procedures, and patient satisfaction) outcomes were extracted. CONCLUSION: Generally favorable outcomes are seen in all flaps. Careful consideration of donor sites for interpolation flaps is needed for optimal cosmetic outcomes. Transposition flaps, including laterally based bilobed and trilobed flaps, created good outcomes, although melolabial transposition flaps may produce poorer outcomes compared with melolabial island pedicle advancement flaps. Caution is needed for rotation flaps to prevent nasal valve/respiratory dysfunction due to alar crease contracture or ridge elevation. Further research is needed.