Pediatric Oral Health Online Education for Rural and Migrant Head Start Programs in the United States.

Children living in rural and migrant areas in the United States disproportionately suffer from poor oral health. Additionally, there continues to be a shortage of pediatric dentists practicing in rural/migrant areas. The purpose of this formative research study was to assess whether staff, teachers and families from rural/migrant Head Start/Early Head Start (HS/EHS) programs in California were receptive to oral health online education workshops conducted by pediatric dental residents who were assisted by bilingual (English and Spanish) community oral health workers (COHWs). Our findings suggest that partnering pediatric dental residents with bilingual COHWs to educate HS/EHS teachers, staff and parents on oral health care in rural/migrant areas could result in a rewarding experience for pediatric dentists that might lead them to practice in these communities upon graduation from their residency program. Furthermore, the positive feedback received from the teachers, staff and parents who participated in the workshops indicates they were receptive to receiving oral health information related to oral health literacy from the dental providers and COHWs. COHWs can help increase access to oral health care by serving as a bridge between families and providers by relaying information in a cultural, linguistic and sensitive manner.

Selective Internal Radiation Therapy Using Y-90 Resin Microspheres for Metastatic Colorectal Cancer: An Updated Systematic Review and Network Meta-Analysis.

INTRODUCTION: This literature review and exploratory network meta-analysis (NMA) aimed to compare the clinical effectiveness and tolerability of selective internal radiation therapy (SIRT) using yttrium-90 (Y-90) resin microspheres, regorafenib (REG), trifluridine-tipiracil (TFD/TPI), and best supportive care (BSC) in adult patients with chemotherapy-refractory or chemotherapy-intolerant metastatic colorectal cancer (mCRC). METHODS: In light of recently published data, the literature was searched to complement and update a review published in 2018. Studies up to December 2022 comparing two or more of the treatments and reporting overall survival (OS), progression-free survival (PFS), or incidence of adverse events (AE) were included. The NMA compared hazard ratios (HRs) for OS and PFS using Markov chain Monte Carlo techniques. RESULTS: Fifteen studies were included, with eight studies added (none addressing SIRT). All active treatments improved OS in relation to BSC. SIRT had the longest OS among all treatments, although without statistically significant differences (HR [95% credible interval] for SIRT, 0.48 [0.27, 0.87]; TFD/TPI, 0.62 [0.46, 0.83]; REG, 0.78 [0.57, 1.05]) in a fixed effects model. Information regarding SIRT was insufficient for PFS analysis, and TFD/TPI was the best intervention (HR 2.26 [1.6, 3.18]). One SIRT study reported radioembolization-induced liver disease in > 10% of the sample; this was symptomatically managed. Non-haematological AEs (hand-foot skin reaction, fatigue, diarrhoea, hypertension, rash or desquamation) were more common with REG, while haematological events (neutropoenia, leukopenia, and anaemia) were more common with TFD/TPI. CONCLUSION: Current evidence supports SIRT treatment in patients with chemotherapy-refractory or chemotherapy-intolerant mCRC compared to newer oral agents, with comparable OS and low incidence of AEs.

Claudin 18.2 as a New Biomarker in Gastric Cancer-What Should We Know?

Gastric cancer (GC) remains a formidable global health challenge, ranking among the top-five causes of cancer-related deaths worldwide. The majority of patients face advanced stages at diagnosis, with a mere 6% five-year survival rate. First-line treatment for metastatic GC typically involves a fluoropyrimidine and platinum agent combination; yet, predictive molecular markers have proven elusive. This review navigates the evolving landscape of GC biomarkers, with a specific focus on Claudin 18.2 (CLDN18.2) as an emerging and promising target. Recent phase III trials have unveiled the efficacy of Zolbetuximab, a CLDN18.2-targeting antibody, in combination with oxaliplatin-based chemotherapy for CLDN18.2-positive metastatic GC. As this novel therapeutic avenue unfolds, understanding the nuanced decision making regarding the selection of anti-CLDN18.2 therapies over other targeted agents in metastatic GC becomes crucial. This manuscript reviews the evolving role of CLDN18.2 as a biomarker in GC and explores the current status of CLDN18.2-targeting agents in clinical development. The aim is to provide concise insights into the potential of CLDN18.2 as a therapeutic target and guide future clinical decisions in the management of metastatic GC.

Current clinical practice in the management of Brazilian patients with potentially resectable pancreatic ductal adenocarcinoma (PDAC).

BACKGROUND AND OBJECTIVES: We aimed to describe the routine clinical practice of physicians involved in the treatment of patients with localized pancreatic ductal adenocarcinoma (PDAC) in Brazil. METHODS: Physicians were invited through email and text messages to participate in an electronic survey sponsored by the Brazilian Gastrointestinal Tumor Group (GTG) and the Brazilian Society of Surgical Oncology (SBCO). We evaluated the relationship between variable categories numerically with false discovery rate-adjusted Fisher's exact test p values and graphically with Multiple Correspondence Analysis. RESULTS: Overall, 255 physicians answered the survey. Most (52.5%) were medical oncologists, treated patients predominantly in the private setting (71.0%), and had access to multidisciplinary tumor boards (MTDTB; 76.1%). Medical oncologists were more likely to describe neoadjuvant therapy as beneficial in the resectable setting and surgeons in the borderline resectable setting. Most physicians would use information on risk factors for early recurrence, frailty, and type of surgery to decide treatment strategy. Doctors working predominantly in public institutions were less likely to have access to MTDTB and to consider FOLFIRINOX the most adequate regimen in the neoadjuvant setting. CONCLUSIONS: Considerable differences exist in the management of localized PDAC, some of them possibly explained by the medical specialty, but also by the funding source of health care.

Targeting KRAS in Pancreatic Ductal Adenocarcinoma: The Long Road to Cure.

Pancreatic ductal adenocarcinoma (PDAC) remains an important cause of cancer-related mortality, and it is expected to play an even bigger part in cancer burden in the years to come. Despite concerted efforts from scientists and physicians, patients have experienced little improvement in survival over the past decades, possibly because of the non-specific nature of the tested treatment modalities. Recently, the discovery of potentially targetable molecular alterations has paved the way for the personalized treatment of PDAC. Indeed, the central piece in the molecular framework of PDAC is starting to be unveiled. KRAS mutations are seen in 90% of PDACs, and multiple studies have demonstrated their pivotal role in pancreatic carcinogenesis. Recent investigations have shed light on the differences in prognosis as well as therapeutic implications of the different KRAS mutations and disentangled the relationship between KRAS and effectors of downstream and parallel signaling pathways. Additionally, the recognition of other mechanisms involving KRAS-mediated pathogenesis, such as KRAS dosing and allelic imbalance, has contributed to broadening the current knowledge regarding this molecular alteration. Finally, KRAS G12C inhibitors have been recently tested in patients with pancreatic cancer with relative success, and inhibitors of KRAS harboring other mutations are under clinical development. These drugs currently represent a true hope for a meaningful leap forward in this dreadful disease.

HORMONET: a phase II trial of tamoxifen for estrogen/progesterone receptor-positive neuroendocrine tumors.

Background: Nearly 30% of neuroendocrine tumors (NETs) have evidence of immunohistochemical (IHC) expression of estrogen (ER) and/or progesterone (PR) receptors. Therefore, targeting ER/PR may offer an effective NET-directed treatment to select patients. Methods: We conducted a multicenter Simon two-stage single-arm phase II trial of tamoxifen in patients with metastatic, progressive NETs. Eligible patients had positive IHC expression of ER and/or PR ⩾ 1%. Prior therapy with somatostatin analogs was required for progressing/functioning cases. Main exclusion criterion was aggressive disease requiring cytotoxic therapy. The primary end point was disease control rate (DCR) at week 24 by Response Evaluation Criteria in Solid Tumors version 1.1. We planned to enroll 23 patients in the first stage, to reach a DCR at week 24 of 70% (versus 50%); if ⩾12 patients reached the primary end point, a total of 37 would be included. Results: From February 2019 to February 2022, 23 out of 59 patients were eligible and enrolled: 15 (65%) were females; the most common sites were pancreas (11; 48%) and small bowel (6; 26%). In all, 13 patients (56.5%) had G2 NETs. At a median follow-up of 27 months, 13 patients (56.5%) had stable disease at week 24 and median progression-free survival (PFS) was 7.9 months [interquartile range (IQR): 3.7-12.1]. The best response was stable disease in 13 patients, with most patients experiencing minor tumor growth. Median PFS times were not significantly different according to ER/PR < or ⩾30% (p = 0.49) or ER versus PR expression (p = 0.19). One patient experienced grade 2 constipation. Conclusion: Tamoxifen for ER-/PR-positive NETs patients is safe but offers modest antitumor effects. Trial registry name: Study of Tamoxifen in Well Differentiated Neuroendocrine Tumors and Hormone Receptor Positive Expression (HORMONET). URL: https://clinicaltrials.gov/ct2/show/NCT03870399?term=03870399&draw=2&rank=1. Registration number: NCT03870399.

Mature tertiary lymphoid structures are key niches of tumour-specific immune responses in pancreatic ductal adenocarcinomas.

OBJECTIVE: To better understand the immune microenvironment of pancreatic ductal adenocarcinomas (PDACs), here we explored the relevance of T and B cell compartmentalisation into tertiary lymphoid structures (TLSs) for the generation of local antitumour immunity. DESIGN: We characterised the functional states and spatial organisation of PDAC-infiltrating T and B cells using single-cell RNA sequencing (scRNA-seq), flow cytometry, multicolour immunofluorescence, gene expression profiling of microdissected TLSs, as well as in vitro assays. In addition, we performed a pan-cancer analysis of tumour-infiltrating T cells using scRNA-seq and sc T cell receptor sequencing datasets from eight cancer types. To evaluate the clinical relevance of our findings, we used PDAC bulk RNA-seq data from The Cancer Genome Atlas and the PRINCE chemoimmunotherapy trial. RESULTS: We found that a subset of PDACs harbours fully developed TLSs where B cells proliferate and differentiate into plasma cells. These mature TLSs also support T cell activity and are enriched with tumour-reactive T cells. Importantly, we showed that chronically activated, tumour-reactive T cells exposed to fibroblast-derived TGF-ß may act as TLS organisers by producing the B cell chemoattractant CXCL13. Identification of highly similar subsets of clonally expanded CXCL13 + tumour-infiltrating T cells across multiple cancer types further indicated a conserved link between tumour-antigen recognition and the allocation of B cells within sheltered hubs in the tumour microenvironment. Finally, we showed that the expression of a gene signature reflecting mature TLSs was enriched in pretreatment biopsies from PDAC patients with longer survival after receiving different chemoimmunotherapy regimens. CONCLUSION: We provided a framework for understanding the biological role of PDAC-associated TLSs and revealed their potential to guide the selection of patients for future immunotherapy trials.

Therapy Sequencing in Patients With Advanced Neuroendocrine Neoplasms.

Neuroendocrine neoplasms (NENs) comprise a beautifully complicated, exciting landscape of histologies and clinical behaviors. However, the nuanced complexity of low- and high-grade variants can easily overwhelm both patients and providers. In this chapter, we review the ever-expanding literature on both functioning and nonfunctioning small bowel and pancreatic NENs, touching on somatostatin analogs, hepatic-directed therapies, small molecules, radiopharmaceuticals, immunotherapy, cytotoxic chemotherapy, and new promising agents. Furthermore, we suggest some strategies to address the most challenging scenarios seen in clinical practice, including sequencing of agents, treatment of carcinoid syndrome, and options for well-differentiated high-grade disease.

Current Treatment of Potentially Resectable Pancreatic Ductal Adenocarcinoma: A Medical Oncologist's Perspective.

Pancreatic cancer has traditionally been associated with a dismal prognosis, even in early stages of the disease. In recent years, the introduction of newer generation chemotherapy regimens in the adjuvant setting has improved the survival of patients treated with upfront resection. However, there are multiple theoretical advantages to deliver early systemic therapy in patients with localized pancreatic cancer. So far, the evidence supports the use of neoadjuvant therapy for patients with borderline resectable pancreatic cancer. The benefit of this treatment sequence for patients with resectable disease remains elusive. In this review, we summarize the data on adjuvant therapy for pancreatic cancer and describe which evidence backs the use of neoadjuvant therapy. Additionally, we address important issues faced in clinical practice when treating patients with localized pancreatic cancer.

The Clinical Laboratory Is an Integral Component to Health Care Delivery : An Expanded Representation of the Total Testing Process.

OBJECTIVES: Developing an expanded representation of the total testing process that includes contemporary elements of laboratory practice can be useful to understanding and optimizing testing workflows across clinical laboratory and patient care settings. METHODS: Published literature and meeting reports were used by the coauthors to inform the development of the expanded representation of the total testing process and relevant examples describing its uses. RESULTS: A visual representation of the total testing process was developed and contextualized to patient care scenarios using a number of examples covering the detection of blood culture contamination, use of next-generation sequencing, and pharmacogenetic testing. CONCLUSIONS: The expanded representation of the total testing process can serve as a model and framework to document and improve the use of clinical testing within the broader context of health care delivery. This representation recognizes increased engagement among clinical laboratory professionals with patients and other health care providers as essential to making informed decisions. The increasing use of data is highlighted as important to ensuring quality, appropriate test utilization, and sustaining an efficient workflow across clinical laboratory and patient care settings. Maintaining a properly resourced and competent workforce is also featured as an essential component to the testing process.

Effective Access to Laboratory Test Results: A Health Equity Issue that Enhances Diagnostic Excellence.

Access to laboratory test results through patient portals is a health equity issue for patients with limited English proficiency (LEP), particularly for Spanish-speaking patients, the largest minority group in the USA. Gaps ranging from linguistic, cultural, and socioeconomic disparities to lack of systematic approaches (e.g., implementation of specific support protocols, policies) are among the identified factors that limit LEP patients' access to patient portals. This paper summarizes initiatives healthcare providers, laboratory professionals, and portal developers can use to address disparities that affect >26 million LEPs while improving their health equity.

Impact of Granulocyte Colony-Stimulating Factor (G-CSF) on the Outcomes of Patients With Metastatic Pancreatic Adenocarcinoma (MPA) During First-Line Treatment With FOLFIRINOX: A Single-Center Retrospective Analysis.

INTRODUCTION: The role of primary prophylaxis (PP) with granulocyte colony-stimulating factor (G-CSF) for patients with metastatic pancreatic adenocarcinoma (MPA) treated with FOLFIRINOX is unknown. We aimed to compare the frequencies of grades 3 or 4 neutropenia (G3/4N) and febrile neutropenia (FN) and survival outcomes according to the use of PP. METHODS: This is a retrospective study. We included patients with pathologically confirmed MPA treated with FOLFIRINOX in first-line. Patients who received primary prophylaxis (PP group) were compared to patients who received secondary or no G-CSF (no-PP group). Overall survival (OS) and progression-free survival (PFS) were evaluated using the standard Cox proportional hazard model. To account for potential biases, we performed sensitivity analyses excluding patients who received secondary prophilaxis and treating G-CSF as a time-dependent covariate in extended Cox proportional hazard models. RESULTS: The study population consisted of 123 patients. PP was used by 75 patients (61.0%). G3/4 N occurred more frequently among patients without PP (10.7 vs 41.7%; P < .001). There was no difference in the frequency of FN between groups (5.3 vs 8.3%; P = .710). In multivariate analysis, PP was associated with a trend toward improved OS (HR = .66; 95% confidence interval [95% CI] .41 - 1.07; P = .094). In the multivariate model excluding patients with secondary prophylaxis (HR = .54; 95% CI 0.32 - .91; P = .022) and in the time-dependent model (HR = .47; 95% CI 0.28 - .80; P = .005), PP was associated with statistically superior OS. CONCLUSIONS: Despite the reduction in the frequency of G3/4N, the risk of FN among patients treated with FOLFIRINOX without G-CSF is too low to justify its use in a routine basis. However, given the potential of G-CSF to improve survival in this setting, further studies are warranted to assess its role during treatment with FOLFIRINOX for patients with MPA.

Current Molecular Profile of Gastrointestinal Stromal Tumors and Systemic Therapeutic Implications.

Gastrointestinal stromal tumors (GISTs) are malignant mesenchymal tumors arising from the intestinal pacemaker cells of Cajal. They compose a heterogenous group of tumors due to a variety of molecular alterations. The most common gain-of-function mutations in GISTs are either in the KIT (60-70%) or platelet-derived growth factor receptor alpha (PDGFRA) genes (10-15%), which are mutually exclusive. However, a smaller subset, lacking KIT and PDGFRA mutations, is considered wild-type GISTs and presents distinct molecular findings with the activation of different proliferative pathways, structural chromosomal and epigenetic changes, such as inactivation of the NF1 gene, mutations in the succinate dehydrogenase (SDH), BRAF, and RAS genes, and also NTRK fusions. Currently, a molecular evaluation of GISTs is imperative in many scenarios, aiding in treatment decisions from the (neo)adjuvant to the metastatic setting. Here, we review the most recent data on the molecular profile of GISTs and highlight therapeutic implications according to distinct GIST molecular subtypes.

PD-L1 expression in gastric and gastroesophageal junction cancer patients treated with perioperative chemotherapy.

BACKGROUND AND OBJECTIVES: The incidence, predictive, and prognostic impact of programmed cell death (PD-L1) expression in gastric (GC) and gastroesophageal junction tumors (GEJC) treated with perioperative chemotherapy is poorly understood. We aimed to assess PD-L1 expression by immunohistochemistry (IHC) in both pre and posttreatment specimens evaluating its impact on pathological response and survival outcomes. METHODS: Retrospective cohort of patients with GC and GEJ tumors treated in a single western cancer center between 2007 and 2017. PD-L1 expression was assessed by IHC before and after neoadjuvant chemotherapy, in surgical samples, and reported as combined positive score (CPS). CPS > 1% was tested for its association with pathological response and overall survival (OS). RESULTS: We were able to assess PD-L1 expression in at least one tissue sample from 155 subjects. PD-L1 positivity rate was 20%. In 74 paired samples, a 21% discordance between PD-L1 expression in biopsy sample and surgical specimen was observed. With a median follow-up period of 60.3 months, 5-years disease-free survival was 60.5% with a median OS not reached. PD-L1 expression was neither associated with pathological response or survival outcomes. CONCLUSIONS: PD-L1 expression in the setting of locally advanced GC tumors was relatively low and can vary considering the tissue sample analyzed. This expression had no association with survival or pathological response in this population.

Patterns of disease relapse and posttreatment follow-up of patients with resected pancreatic adenocarcinoma: A single-center analysis.

BACKGROUND AND OBJECTIVES: To describe the patterns of disease relapse and follow-up of patients with resected pancreatic adenocarcinoma. Additionally, we looked at patients' characteristics at relapse and survival. METHODS: We included patients with potentially resectable pancreatic adenocarcinoma diagnosed from 2008 to 2018 who were submitted to resection with clear macroscopic margins and started posttreatment surveillance. RESULTS: The study population consists of 73 patients. The median interval between imaging studies was 3.2 months during the first 2 years of follow-up and 5.1 months thereafter. Forty-eight patients (65.8%) experienced disease relapse. The most frequent single site of relapse was locoregional (N = 21; 43.8%). At relapse, 31 patients (64.6%) were symptomatic and forty-two patients (87.6%) had Eastern Cooperative Oncology Group performance status 0 or 1. Most patients were able to undergo additional anticancer therapy (N = 41; 85.4%). Patients with asymptomatic relapses experienced longer median postrelapse survival (25.4 vs. 11.3 months; p = 0.015). CONCLUSIONS: A follow-up protocol that included imaging studies every 3 months in the first 2 years and every 6 months thereafter is able to diagnose disease relapse when patients have adequate performance status and are still able to undergo additional anticancer treatment.

Evaluation of prognostic factors in patients undergoing first-line chemotherapy for advanced biliary tract cancer: a retrospective analysis from a South American cancer centre.

INTRODUCTION: Biliary tract cancers (BTCs) are rare tumours with regional differences. Prognostic factors are poorly understood. Gemcitabine + platinum (GP) is the standard first-line chemotherapy in metastatic patients. We aimed to search for prognostic factors in patients with advanced disease in a cancer centre in South America. METHODS: We conducted a retrospective analysis of patients with advanced BTC treated with chemotherapy. Variables were age (< or ≥70 years), Eastern Cooperative Oncology Group (ECOG) performance status (0/1 versus 2/3), gender, primary site (intrahepatic (IHC), extrahepatic (EHC), gallbladder (GB)), staging (locally advanced versus metastatic), metastatic sites, albumin (>3.5 g/dL versus <3.5 g/dL), biliary obstruction and first-line chemotherapy (GP, 5FU-based or single-agent). Cox regression method was used to explore factors. RESULTS: From 2010 to 2017, 104 patients were included. Median age was 62 years (32-86) and 22.1% were older than 70 years. Most patients had ECOG performance status 0/1 (63.4%), were female (51.9%) and were metastatic (82.7%). Bone metastases were found in 19.2%. Primary IHC, EHC and GB were 54.8%, 36.5% and 8.7%, respectively. GP was used by 79.8%. Median follow-up was 32.4 months. Median overall survival (mOS) was 11.4 months. In univariate analysis, male (p = 0.007), albumin < 3.5 g/dL (p = 0.001), biliary obstruction (p = 0.006), 5FU-based (p = 0.006) and single-agent (p < 0.0001) were associated with worse OS. ECOG performance status 2/3 (p = 0.058) and bone metastases (p = 0.051) were marginally related. In multivariate analysis, male (p = 0.003), bone metastases (p = 0.023), biliary obstruction (p = 0.001), 5FU-based (p = 0.016) and single-agent (p = 0.023) were independently associated with inferior OS. CONCLUSION: In this retrospective study, we observed that male patients, bone metastases, biliary obstruction and regimens other than GP had worse survival. Larger studies should be conducted to confirm our findings.

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.

Short-term survival of patients with advanced pancreatic cancer admitted to intensive care unit: a retrospective cohort study.

Background: Little is known about the outcomes of patients with advanced pancreatic cancer admitted to the intensive care unit (ICU) due to medical complications. We designed a study to evaluate their short-term (30-day) survival, predictors of short-term survival and chances of additional chemotherapy. Methods: We reviewed all patients with advanced (stage III or IV) pancreatic adenocarcinoma admitted to an ICU in a dedicated Brazilian cancer centre from 2009 to 2018 due to medical reasons. We fitted multivariate regression models to identify predictors of 30-day survival and additional systemic chemotherapy. Results: The study population consisted of 171 patients. Ninety-four patients (55.0%) had Eastern Cooperative Oncology Group (ECOG) performance status 2-4 and 146 (85.4%) had metastatic disease. Most patients (N = 75; 43.9%) were admitted to the ICU during first-line treatment. Median overall survival was 32 days (95% confidence interval (95% CI): 20-49). Survival rate at 30 days was 50.6%. ECOG performance status 2-4 was the only variable associated with lower probability of survival at 30 days in multivariate analysis (odds ratio: 0.28; 95% CI: 0.14-0.54; p < 0.001). Overall, 58 patients (33.9%) received additional chemotherapy and among all patients, 13.5% experienced clinical benefit from this treatment. Conclusion: Patients with advanced pancreatic cancer admitted to the ICU for medical reasons have a dismal prognosis. Early palliative care and refined tools to establish those who would benefit from an ICU trial could help improve patients' care.

The CRISPR toolbox for the gram-positive model bacterium Bacillus subtilis.

CRISPR has revolutionized the way we engineer genomes. Its simplicity and modularity have enabled the development of a great number of tools to edit genomes and to control gene expression. This powerful technology was first adapted to Bacillus subtilis in 2016 and has been intensely upgraded since then. Many tools have been successfully developed to build a CRISPR toolbox for this Gram-positive model and important industrial chassis. The toolbox includes tools, such as double-strand and single-strand cutting CRISPR for point mutation, gene insertion, and gene deletion up to 38 kb. Moreover, catalytic dead Cas proteins have been used for base editing, as well as for the control of gene expression (CRISPRi and CRISPRa). Many of these tools have been used for multiplex CRISPR with the most successful one targeting up to six loci simultaneously for point mutation. However, tools for efficient multiplex CRISPR for other functionalities are still missing in the toolbox. CRISPR engineering has already resulted in efficient protein and metabolite-producing strains, demonstrating its great potential. In this review, we cover all the important additions made to the B. subtilis CRISPR toolbox since 2016, and strain developments fomented by the technology.