Exploring the prognostic significance of arm-level copy number alterations in triple-negative breast cancer.

Somatic copy number alterations (SCNAs) are prevalent in cancer and play a significant role in both tumorigenesis and therapeutic resistance. While focal SCNAs have been extensively studied, the impact of larger arm-level SCNAs remains poorly understood. Here, we investigated the association between arm-level SCNAs and overall survival in triple-negative breast cancer (TNBC), an aggressive subtype of breast cancer lacking targeted therapies. We identified frequent arm-level SCNAs, including 21q gain and 7p gain, which correlated with poor overall survival in TNBC patients. Further, we identified the expression of specific genes within these SCNAs associated with survival. Notably, we found that the expression of RIPK4, a gene located on 21q, exhibited a strong correlation with poor overall survival. In functional assays, we demonstrated that targeting Ripk4 in a murine lung metastatic TNBC model significantly reduced tumor burden, improved survival, and increased CD4+ and CD8+ T cell infiltration. RIPK4 enhanced the survival of triple-negative breast cancer cells at secondary sites, thereby facilitating the formation of metastatic lesions. Our findings highlight the significance of arm-level SCNAs in breast cancer progression and identify RIPK4 as a putative driver of TNBC metastasis and immunosuppression.

Comparative efficacy and safety of Pneumocystis jirovecii pneumonia prophylaxis regimens for people living with HIV: a systematic review and network meta-analysis of randomized controlled trials.

BACKGROUND: Pneumocystis jirovecii pneumonia (PCP) is a common opportunistic infection among people living with HIV (PWH), particularly among new and untreated cases. Several regimens are available for the prophylaxis of PCP, including trimethoprim-sulfamethoxazole (TMP-SMX), dapsone-based regimens (DBRs), aerosolized pentamidine (AP), and atovaquone. OBJECTIVES: To compare the efficacy and safety of PCP prophylaxis regimens in PWH by network meta-analysis. METHODS: DATA SOURCES: Embase, MEDLINE, and CENTRAL from inception to June 21, 2023. STUDY ELIGIBILITY CRITERIA: Comparative randomized controlled trials (RCTs). PARTICIPANTS: PWH. INTERVENTIONS: Regimens for PCP prophylaxis either compared head-to-head or versus no treatment/placebo. ASSESSMENT OF RISK OF BIAS: Cochrane risk-of-bias tool for RCTs 2. METHODS OF DATA SYNTHESIS: Title or abstract and full-text screening and data extraction were performed in duplicate by two independent reviewers. Data on PCP incidence, all-cause mortality, and discontinuation due to toxicity were pooled and ranked by network meta-analysis. Subgroup analyses of primary versus secondary prophylaxis, by year, and by dosage were performed. RESULTS: A total of 26 RCTs, comprising 55 treatment arms involving 7516 PWH were included. For the prevention of PCP, TMP-SMX was ranked the most favourable agent and was superior to DBRs (risk ratio [RR] = 0.54; 95% CI, 0.36-0.83) and AP (RR = 0.53; 95% CI, 0.36-0.77). TMP-SMX was also the only agent with a mortality benefit compared with no treatment/placebo (RR = 0.79; 95% CI, 0.64-0.98). However, TMP-SMX was also ranked as the most toxic agent with a greater risk of discontinuation than DBRs (RR = 1.25; 95% CI, 1.01-1.54) and AP (7.20; 95% CI, 5.37-9.66). No significant differences in PCP prevention or mortality were detected among the other regimens. The findings remained consistent within subgroups. CONCLUSIONS: TMP-SMX is the most effective agent for PCP prophylaxis in PWH and the only agent to confer a mortality benefit; consequently, it should continue to be recommended as the first-line agent. Further studies are necessary to determine the optimal dosing of TMP-SMX to maximize efficacy and minimize toxicity.

Neoadjuvant Chemoimmunotherapy for NSCLC: A Systematic Review and Meta-Analysis.

Importance: To date, no meta-analyses have comprehensively assessed the association of neoadjuvant chemoimmunotherapy with clinical outcomes in non-small cell lung cancer (NSCLC) in randomized and nonrandomized settings. In addition, there exists controversy concerning the efficacy of neoadjuvant chemoimmunotherapy for patients with NSCLC with programmed cell death 1 ligand 1 (PD-L1) levels less than 1%. Objective: To compare neoadjuvant chemoimmunotherapy with chemotherapy by adverse events and surgical, pathological, and efficacy outcomes using recently published randomized clinical trials and nonrandomized trials. Data Sources: MEDLINE and Embase were systematically searched from January 1, 2013, to October 25, 2023, for all clinical trials of neoadjuvant chemoimmunotherapy and chemotherapy that included at least 10 patients. Study Selection: Observational studies and trials reporting the use of neoadjuvant radiotherapy, including chemoradiotherapy, molecular targeted therapy, or immunotherapy monotherapy, were excluded. Main Outcomes and Measures: Surgical, pathological, and efficacy end points and adverse events were pooled using a random-effects meta-analysis. Results: Among 43 eligible trials comprising 5431 patients (4020 males [74.0%]; median age range, 55-70 years), there were 8 randomized clinical trials with 3387 patients. For randomized clinical trials, pooled overall survival (hazard ratio, 0.65; 95% CI, 0.54-0.79; I2 = 0%), event-free survival (hazard ratio, 0.59; 95% CI, 0.52-0.67; I2 = 14.9%), major pathological response (risk ratio, 3.42; 95% CI, 2.83-4.15; I2 = 31.2%), and complete pathological response (risk ratio, 5.52; 95% CI, 4.25-7.15; I2 = 27.4%) favored neoadjuvant chemoimmunotherapy over neoadjuvant chemotherapy. For patients with baseline tumor PD-L1 levels less than 1%, there was a significant benefit in event-free survival for neoadjuvant chemoimmunotherapy compared with chemotherapy (hazard ratio, 0.74; 95% CI, 0.62-0.89; I2 = 0%). Conclusion and Relevance: This study found that neoadjuvant chemoimmunotherapy was superior to neoadjuvant chemotherapy across surgical, pathological, and efficacy outcomes. These findings suggest that patients with resectable NSCLC with tumor PD-L1 levels less than 1% may have an event-free survival benefit with neoadjuvant chemoimmunotherapy.

Risk of infectious adverse events of venetoclax therapy for hematologic malignancies: a systematic review and meta-analysis of RCTs.

ABSTRACT: Venetoclax is a small molecule inhibitor of BCL-2 used in the treatment of acute myelogenous leukemia (AML) and chronic lymphocytic leukemia (CLL). Recent postmarketing studies of ibrutinib, another small molecule inhibitor, suggested that these agents may predispose to opportunistic infections. We sought to systematically review the randomized controlled trial (RCT) evidence of venetoclax to assess whether it predisposes patients to infectious adverse events (IAEs) and neutropenia. We systematically reviewed RCTs comparing venetoclax therapy with active or placebo controls for patients with hematologic malignancies. Data on IAEs and neutropenia were pooled by Bayesian meta-analysis, and we computed the probability of any increased risk (P[risk ratio (RR) > 1]) of IAEs or neutropenic complications. Seven RCTs were included, comprising 2067 patients. In CLL (n = 1032), there was a low probability of increased risk of high-grade (P[RR > 1] = 71.2%) and fatal IAEs (P[RR > 1] = 64.5%) and high-grade neutropenia (P[RR > 1] = 63.4%). There were insufficient data to perform a meta-analysis of IAEs in AML; however, 1 trial suggested an increased risk of IAEs with venetoclax. Furthermore, in AML (n = 642), venetoclax was associated with a high probability of increased risk of high-grade neutropenia (P[RR > 1] = 94.6%) and febrile neutropenia (P[RR > 1] = 90.6%). Our results suggest that venetoclax has a low probability of increased risk of IAEs or neutropenia in CLL. By contrast, there is likely increased risk of high-grade neutropenia and febrile neutropenia in AML. Importantly, our analyses did not identify any specific IAEs that would benefit from routine antimicrobial prophylaxis or pre-emptive testing.

Obesity alters monocyte developmental trajectories to enhance metastasis.

Obesity is characterized by chronic systemic inflammation and enhances cancer metastasis and mortality. Obesity promotes breast cancer metastasis to lung in a neutrophil-dependent manner; however, the upstream regulatory mechanisms of this process remain unknown. Here, we show that obesity-induced monocytes underlie neutrophil activation and breast cancer lung metastasis. Using mass cytometry, obesity favors the expansion of myeloid lineages while restricting lymphoid cells within the peripheral blood. RNA sequencing and flow cytometry revealed that obesity-associated monocytes resemble professional antigen-presenting cells due to a shift in their development and exhibit enhanced MHCII expression and CXCL2 production. Monocyte induction of the CXCL2-CXCR2 axis underlies neutrophil activation and release of neutrophil extracellular traps to promote metastasis, and enhancement of this signaling axis is observed in lung metastases from obese cancer patients. Our findings provide mechanistic insight into the relationship between obesity and cancer by broadening our understanding of the interactive role that myeloid cells play in this process.

Next-generation sequencing of non-small cell lung cancer at a Quebec health care cancer centre.

BACKGROUND: Lung cancer is the leading cause of cancer death in both men and women. Quebec has the highest lung cancer mortality out of all provinces in Canada, believed to be caused by higher smoking rates. Molecular testing for lung cancer is standard of care due to the discovery of actionable driver mutations that can be targeted with tyrosine kinase inhibitors. To date, no detailed molecular testing characterization of Quebec patients with lung cancer using next generation sequencing (NGS) has been performed. MATERIALS AND METHODS: The aim of this study was to describe the genomic landscape of patients with lung cancer (n = 997) who underwent NGS molecular testing at a tertiary care center in Quebec and to correlate it with clinical and pathology variables. RESULTS: Compared to 10 other NGS studies found through a structured search strategy, our cohort had a higher prevalence of KRAS mutations (39.2%) compared to most geographical locations. Additionally, we observed a significant positive association between decreasing age and a higher proportion of KRAS G12C mutations. CONCLUSION: Overall, it remains important to assess institutional rates of actionable driver mutations to help guide governing bodies, fuel clinical trials and create benchmarks for expected rates as quality metrics.

Gender Disparities in Academic Outcomes Among Graduates of a Canadian MD-PhD Program.

PURPOSE: Women have traditionally been underrepresented in MD and MD-PhD training programs. Here, we describe the changing demographics of an MD-PhD Program over three distinct time intervals. METHODS: We designed a 64-question survey and sent it to 47 graduates of the McGill University MD-PhD program in Montréal, Québec, Canada, since its inception in 1985. We also sent a 23-question survey to the 24 students of the program in 2021. The surveys included questions related to demographics, physician-scientist training, research metrics, as well as academic and personal considerations. RESULTS: We collected responses from August 2020 to August 2021 and grouped them into three intervals based on respondent graduation year: 1995-2005 (n = 17), 2006-2020 (n = 23) and current students (n = 24). Total response rate was 90.1% (n = 64/71). We found that there are more women currently in the program compared to the 1995-2005 cohort (41.7% increase, p<0.01). In addition, women self-reported as physician-scientists less frequently than men and reported less protected research time. CONCLUSIONS: Overall, recent MD-PhD alumni represent a more diverse population compared with their earlier counterparts. Identifying barriers to training remains an important step in ensuring MD-PhD trainees become successful physician-scientists.

Single-cell spatial landscape of immunotherapy response reveals mechanisms of CXCL13 enhanced antitumor immunity.

BACKGROUND: Immunotherapy has revolutionized clinical outcomes for patients suffering from lung cancer, yet relatively few patients sustain long-term durable responses. Recent studies have demonstrated that the tumor immune microenvironment fosters tumorous heterogeneity and mediates both disease progression and response to immune checkpoint inhibitors (ICI). As such, there is an unmet need to elucidate the spatially defined single-cell landscape of the lung cancer microenvironment to understand the mechanisms of disease progression and identify biomarkers of response to ICI. METHODS: Here, in this study, we applied imaging mass cytometry to characterize the tumor and immunological landscape of immunotherapy response in non-small cell lung cancer by describing activated cell states, cellular interactions and neighborhoods associated with improved efficacy. We functionally validated our findings using preclinical mouse models of cancer treated with anti-programmed cell death protein-1 (PD-1) immune checkpoint blockade. RESULTS: We resolved 114,524 single cells in 27 patients treated with ICI, enabling spatial resolution of immune lineages and activation states with distinct clinical outcomes. We demonstrated that CXCL13 expression is associated with ICI efficacy in patients, and that recombinant CXCL13 potentiates anti-PD-1 response in vivo in association with increased antigen experienced T cell subsets and reduced CCR2+ monocytes. DISCUSSION: Our results provide a high-resolution molecular resource and illustrate the importance of major immune lineages as well as their functional substates in understanding the role of the tumor immune microenvironment in response to ICIs.

Single-cell spatial landscapes of the lung tumour immune microenvironment.

Single-cell technologies have revealed the complexity of the tumour immune microenvironment with unparalleled resolution1-9. Most clinical strategies rely on histopathological stratification of tumour subtypes, yet the spatial context of single-cell phenotypes within these stratified subgroups is poorly understood. Here we apply imaging mass cytometry to characterize the tumour and immunological landscape of samples from 416 patients with lung adenocarcinoma across five histological patterns. We resolve more than 1.6 million cells, enabling spatial analysis of immune lineages and activation states with distinct clinical correlates, including survival. Using deep learning, we can predict with high accuracy those patients who will progress after surgery using a single 1-mm2 tumour core, which could be informative for clinical management following surgical resection. Our dataset represents a valuable resource for the non-small cell lung cancer research community and exemplifies the utility of spatial resolution within single-cell analyses. This study also highlights how artificial intelligence can improve our understanding of microenvironmental features that underlie cancer progression and may influence future clinical practice.

Single-cell spatial immune landscapes of primary and metastatic brain tumours.

Single-cell technologies have enabled the characterization of the tumour microenvironment at unprecedented depth and have revealed vast cellular diversity among tumour cells and their niche. Anti-tumour immunity relies on cell-cell relationships within the tumour microenvironment1,2, yet many single-cell studies lack spatial context and rely on dissociated tissues3. Here we applied imaging mass cytometry to characterize the immunological landscape of 139 high-grade glioma and 46 brain metastasis tumours from patients. Single-cell analysis of more than 1.1 million cells across 389 high-dimensional histopathology images enabled the spatial resolution of immune lineages and activation states, revealing differences in immune landscapes between primary tumours and brain metastases from diverse solid cancers. These analyses revealed cellular neighbourhoods associated with survival in patients with glioblastoma, which we leveraged to identify a unique population of myeloperoxidase (MPO)-positive macrophages associated with long-term survival. Our findings provide insight into the biology of primary and metastatic brain tumours, reinforcing the value of integrating spatial resolution to single-cell datasets to dissect the microenvironmental contexture of cancer.

Scoping review to evaluate the effects of peer support on the mental health of young adults.

OBJECTIVES: Young adults report disproportionality greater mental health problems compared with the rest of the population with numerous barriers preventing them from seeking help. Peer support, defined as a form of social-emotional support offered by an individual with a shared lived experience, has been reported as being effective in improving a variety of mental health outcomes in differing populations. The objective of this scoping review is to provide an overview of the literature investigating the impact of peer support on the mental health of young adults. DESIGN: A scoping review methodology was used to identify relevant peer-reviewed articles in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines across six databases and Google/Google Scholar. Overall, 17 eligible studies met the inclusion criteria and were included in the review. RESULTS: Overall, studies suggest that peer support is associated with improvements in mental health including greater happiness, self-esteem and effective coping, and reductions in depression, loneliness and anxiety. This effect appears to be present among university students, non-student young adults and ethnic/sexual minorities. Both individual and group peer support appear to be beneficial for mental health with positive effects also being present for those providing the support. CONCLUSIONS: Peer support appears to be a promising avenue towards improving the mental health of young adults, with lower barriers to accessing these services when compared with traditional mental health services. The importance of training peer supporters and the differential impact of peer support based on the method of delivery should be investigated in future research.

Differential Regulation of the Asthmatic Phenotype by the Aryl Hydrocarbon Receptor.

The aryl hydrocarbon receptor (AhR) is a ligand-activated transcription factor that regulates the metabolism of xenobiotics. There is growing evidence that the AhR is implicated in physiological processes such proliferation, differentiation, and immune responses. Recently, a role of the AhR in regulating allergic asthma has been suggested, but whether the AhR also regulates other type of asthma, particularly occupational/irritant-induced asthma, remains unknown. Using AhR-deficient (Ahr-/- ) mice, we compared the function of the AhR in the response to ovalbumin (OVA; allergic asthma) vs. chlorine (Cl2; irritant-induced asthma) exposure. Lung inflammation and airway hyperresponsiveness were assessed 24h after exposure to Cl2 or OVA challenge in Ahr-/- and heterozygous (Ahr+/- ) mice. After OVA challenge, absence of AhR was associated with significantly enhanced eosinophilia and lymphocyte influx into the airways of Ahr-/- mice. There were also increased levels of interleukin-4 (IL-4) and IL-5 in the airways. However, OVA-induced airway hyperresponsiveness was not affected. In the irritant-induced asthma model caused by exposure to Cl2, the AhR did not regulate the inflammatory response. However, absence of AhR reduced Cl2-induced airway hyperresponsiveness. Collectively, these results support a differential role for the AhR in regulating asthma outcomes in response to diverse etiological agents.

Ira Remsen, Osler, the Flexner Report, and the full-time plan.

A famous letter from Sir William Osler to Ira Remsen, dated September 1, 1911, concerns Osler's objections to the full-time plan, whereby clinical professors should focus on research and abstain from private practice. Previous accounts of this well-known episode make little or no mention of the recipient other than his being president of the Johns Hopkins University. Remsen, in retrospect, was uniquely positioned to champion ideas advanced by Abraham Flexner, the General Education Board of the Rockefeller Foundation, and some of Osler's former colleagues at Johns Hopkins, notably William H. Welch. Remsen had previously expressed the need for Hopkins to advance science-based medicine; he had introduced Abraham Flexner to the Carnegie Foundation (which led to the Flexner Report); and he appears to have been the first US-born person to possess both a medical degree and a doctorate in basic science. Caught in the middle of a faculty controversy, Remsen chose not to pursue the matter further for reasons that included a passive administrative style, concerns about his health, and friendship with Osler.

Methionine dependence in tumor cells: The potential role of cobalamin and MMACHC.

Methionine dependence of tumor cell lines, the inability to grow in tissue culture media lacking methionine but supplemented with homocysteine, has been known for decades, but an understanding of the mechanism underlying this phenomenon remains incomplete. Methionine dependence of certain glioma and melanoma cell lines has been linked to alterations in the metabolism of cobalamin (vitamin B12). In the MeWo LC1 melanoma line, complementation analysis demonstrated that the genetic defect affected the same locus mutated in the cblC inborn error of cobalamin metabolism; hypermethylation of the MMACHC promoter was subsequently demonstrated. Analysis of data in the Cancer Cell Line Encyclopedia showed increased MMACHC methylation levels in melanoma lines compared to other types of cancer. RNA sequencing data from isolated tumors, tabulated at the cBioPortal for Cancer Genomics website, showed decreased MMACHC expression compared to other tumors; and methylation data tabulated at the TGGA Wanderer website demonstrated increased MMACHC methylation. These data suggest that disruptions in cobalamin metabolism might play a more general role in methionine dependence, and potentially in the pathogenesis of melanoma cell lines and primary tumors.