PubMed

Cancer Discov. 2021 Jan;2(1):32-53. doi: 10.1158/2643-3230.BCD-20-0155. Epub 2020 Dec 1.

ABSTRACT

Acute myeloid leukemia (AML) is a caricature of normal hematopoiesis driven from leukemia stem cells (LSC) that share some hematopoietic stem cell (HSC) programs including responsiveness to inflammatory signaling. Although inflammation dysregulates mature myeloid cells and influences stemness programs and lineage determination in HSCs by activating stress myelopoiesis, such roles in LSCs are poorly understood. Here, we show that S1PR3, a receptor for the bioactive lipid sphingosine-1-phosphate, is a central regulator that drives myeloid differentiation and activates inflammatory programs in both HSCs and LSCs. S1PR3-mediated inflammatory signatures varied in a continuum from primitive to mature myeloid states across cohorts of patients with AML, each with distinct phenotypic and clinical properties. S1PR3 was high in LSCs and blasts of mature myeloid samples with linkages to chemosensitivity, whereas S1PR3 activation in primitive samples promoted LSC differentiation leading to eradication. Our studies open new avenues for therapeutic target identification specific for each AML subset. SIGNIFICANCE: S1PR3 is a novel regulator of myeloid fate in normal hematopoiesis that is heterogeneously expressed in AML. S1PR3 marks a subset of less primitive AML cases with a distinct inflammatory signature and therefore has clinical implications as both a therapeutic target and a biomarker to distinguish primitive from mature AML.See related commentary by Yang et al., p. 3.This article is highlighted in the In This Issue feature, p. 1.

PMID:34238756 | DOI:10.1158/2643-3230.BCD-20-0155

Oncologist. 2021 Jul 3. doi: 10.1002/onco.13890. Online ahead of print.

ABSTRACT

BACKGROUND: In Ontario, Canada, patient-reported outcome (PRO) evaluation through the Edmonton Symptom Assessment System (ESAS) has been integrated into clinical workflow since 2007. As stage IV non-small cell lung cancer (NSCLC) is associated with substantial disease and treatment-related morbidity, this province-wide study investigated moderate to severe symptom burden in this population.

MATERIALS AND METHODS: ESAS collected from patients with stage IV NSCLC diagnosed between 2007 and 2018 linked to the Ontario provincial health care system database were studied. ESAS acquired within 12 months following diagnosis were analyzed and the proportion reporting moderate to severe scores (ESAS ≥4) in each domain was calculated. Predictors of moderate to severe scores were identified using multivariable Poisson regression models with robust error variance.

RESULTS: Of 22,799 patients, 13,289 (58.3%) completed ESAS (84,373 assessments) in the year following diagnosis. Patients with older age, with high comorbidity, and not receiving active cancer therapy had lower ESAS completion. The majority (94.4%) reported at least one moderate to severe symptom. The most prevalent were tiredness (84.1%), low well-being (80.7%), low appetite (71.7%), and shortness of breath (67.8%). Most symptoms peaked at diagnosis and, while declining, remained high in the following year. On multivariable analyses, comorbidity, low income, nonimmigrants, and urban residency were associated with moderate to severe symptoms. Moderate to severe scores in all ESAS domains aside from anxiety were associated with radiotherapy within 2 weeks prior, whereas drowsiness, low appetite and well-being, nausea, and tiredness were associated with systemic therapy within 2 weeks prior.

CONCLUSION: This province-wide PRO analysis showed moderate to severe symptoms were prevalent and persistent among patients with metastatic NSCLC, underscoring the need to address supportive measures in this population especially around treatments.

IMPLICATIONS FOR PRACTICE: In this largest study of lung cancer patient-reported outcomes (PROs), stage IV non-small cell lung cancer patients had worse moderate-to-severe symptoms than other metastatic malignancies such as breast or gastrointestinal cancers when assessed with similar methodology. Prevalence of moderate-to-severe symptoms peaked early and remained high during the first year of follow-up. Symptom burden was associated with recent radiation and systemic treatments. Early and sustained PRO collection is important to detect actionable symptom progression, especially around treatments. Vulnerable patients (e.g., older, high comorbidity) who face barriers in attending in-person clinic visits had lower PRO completion. Virtual PRO collection may improve completion.

PMID:34216415 | DOI:10.1002/onco.13890

Elife. 2021 Jul 2;10:e64951. doi: 10.7554/eLife.64951.

ABSTRACT

Cell cycle duration changes dramatically during development, starting out fast to generate cells quickly and slowing down over time as the organism matures. The cell cycle can also act as a transcriptional filter to control the expression of long gene transcripts, which are partially transcribed in short cycles. Using mathematical simulations of cell proliferation, we identify an emergent property that this filter can act as a tuning knob to control gene transcript expression, cell diversity, and the number and proportion of different cell types in a tissue. Our predictions are supported by comparison to single-cell RNA-seq data captured over embryonic development. Additionally, evolutionary genome analysis shows that fast-developing organisms have a narrow genomic distribution of gene lengths while slower developers have an expanded number of long genes. Our results support the idea that cell cycle dynamics may be important across multicellular animals for controlling gene transcript expression and cell fate.

PMID:34212855 | PMC:PMC8279763 | DOI:10.7554/eLife.64951

J Mol Biol. 2021 Jun 24;433(18):167115. doi: 10.1016/j.jmb.2021.167115. Online ahead of print.

ABSTRACT

PDZ domains are key players in signalling pathways. These modular domains generally recognize short linear C-terminal stretches of sequences in proteins that organize the formation of complex multi-component assemblies. The development of new methodologies for the characterization of the molecular principles governing these interactions is critical to fully understand the functional diversity of the family and to elucidate biological functions for family members. Here, we applied an in vitro evolution strategy to explore comprehensively the capacity of PDZ domains for specific recognition of different amino acids at a key position in C-terminal peptide ligands. We constructed a phage-displayed library of the Erbin PDZ domain by randomizing the binding site-2 and adjacent residues, which are all contained in helix α2, and we selected for variants binding to a panel of peptides representing all possible position-2 residues. This approach generated insights into the basis for the common natural class I and II specificities, demonstrated an alternative basis for a rare natural class III specificity for Asp-2, and revealed a novel specificity for Arg-2 that has not been reported in natural PDZ domains. A structure of a PDZ-peptide complex explained the minimum requirement for switching specificity from class I ligands containing Thr/Ser-2 to class II ligands containing hydrophobic residues at position-2. A second structure explained the molecular basis for the specificity for ligands containing Arg-2. Overall, the evolved PDZ variants greatly expand our understanding of site-2 specificities and the variants themselves may prove useful as building blocks for synthetic biology.

PMID:34171344 | DOI:10.1016/j.jmb.2021.167115