Showing papers by "John Douglas Mcpherson published in 2022"
TL;DR: In this paper , the authors used multivariable Cox proportional hazards regression models to evaluate the association between total pesticide exposure from CalEnviroScreen 3.0 and individual exposure from geographic land use data and lymphoma-specific and overall survival.
Abstract: There is evidence indicating that pesticide exposure is a risk factor for non-Hodgkin lymphoma (NHL) development. However, the association between pesticide exposure and NHL survival is not well-established.Using the California Cancer Registry, we identified patients with a first primary diagnosis of NHL from 2010 to 2016 and linked these patients with CalEnviroScreen 3.0 to obtain production agriculture pesticide exposure to 70 chemicals from the state-mandated Pesticide Use Reporting (PUR) by census tract from 2012 to 2014. In addition, data from PUR was integrated into a geographic information system that employs land-use data to estimate cumulative exposure to specific pesticides previously associated with NHL (glyphosate, organophosphorus, carbamate, phenoxyherbicide, and 2,4-dimethylamine salt) between 10 years prior up to 1 year after NHL diagnosis. Multivariable Cox proportional hazards regression models were used to evaluate the association between total pesticide exposure from CalEnviroScreen 3.0 and individual pesticide exposure from geographic land use data and lymphoma-specific and overall survival.Among 35,808 NHL patients identified, 44.2% were exposed to pesticide in their census tract of residence. Glyphosate, organophosphorus, carbamate, phenoxyherbicide, and 2,4-dimethylamine salt exposure was observed in 34.1%, 26.0%, 10.6%, 14.0%, and 12.8% of NHL patients, respectively. Total pesticide exposure at the time of diagnosis was not associated with lymphoma-specific or overall survival. In addition, no association was consistently found between glyphosate, organophosphorus, carbamate, phenoxyherbicide, and 2,4 dimethylamine salt exposure and lymphoma-specific or overall survival.Although we found no consistent associations between agricultural pesticide exposure at the neighborhood level and worse survival, these results provide a platform for designing future studies to determine the association between pesticide and NHL.
1 citations
TL;DR: In this paper , a 76-year-old woman presented with a history of multiple, distinct primary tumors, including childhood thymoma, thyroid cancer, two melanomas, two breast cancers, a solitary fibrous tumor, and metastasized lung cancer.
TL;DR: A unique subpopulation of cells with low glucose uptake (NBDG-low) in B-ALL was discovered and, despite their quiescence characteristics, once transplanted in mice, showed potent leukemia initiating capacity.
Abstract: In leukemia, a distinct subpopulation of cancer-initiating cells called leukemia stem cells (LSCs) is believed to drive population expansion and tumor growth. Failing to eliminate LSCs may result in disease relapse regardless of the amount of non-LSCs destroyed. The first step in targeting and eliminating LSCs is to identify and characterize them. Acute precursor B lymphoblastic leukemia (B-ALL) cells derived from patients were incubated with fluorescent glucose analog 2-(N-(7-Nitrobenz-2-oxa-1, 3-diazol-4-yl) Amino)-2-Deoxyglucose (NBDG) and sorted based on NBDG uptake. Cell subpopulations defined by glucose uptake were then serially transplanted into mice and evaluated for leukemia initiating capacity. Gene expression profiles of these cells were characterized using RNA-Sequencing (RNA-Seq). A distinct population of NBDG-low cells was identified in patient B-ALL samples. These cells are a small population (1.92% of the entire leukemia population), have lower HLA expression, and are smaller in size (4.0 to 7.0 μm) than the rest of the leukemia population. All mice transplanted with NBDG-low cells developed leukemia between 5 and 14 weeks, while those transplanted with NBDG-high cells did not develop leukemia (p ≤ 0.0001-0.002). Serial transplantation of the NBDG-low mouse model resulted in successful leukemia development. NBDG-medium (NBDG-med) populations also developed leukemia. Interestingly, comprehensive molecular characterization of NBDG-low and NBDG-med cells from patient-derived xenograft (PDX) models using RNA-Seq revealed a distinct profile of 2,162 differentially-expressed transcripts (DETs) (p<0.05) with 70.6% down-regulated in NBDG-low cells. Hierarchical clustering of DETs showed distinct segregation of NBDG-low from NBDG-med and NBDG-high groups with marked transcription expression alterations in the NBDG-low group consistent with cancer survival. In conclusion, A unique subpopulation of cells with low glucose uptake (NBDG-low) in B-ALL was discovered. These cells, despite their quiescence characteristics, once transplanted in mice, showed potent leukemia initiating capacity. Although NBDG-med cells also initiated leukemia, gene expression profiling revealed a distinct signature that clearly distinguishes NBDG-low cells from NBDG-med and the rest of the leukemia populations. These results suggest that NBDG-low cells may represent quiescent LSCs. These cells can be activated in the appropriate environment in vivo, showing leukemia initiating capacity. Our study provides insight into the biologic mechanisms of B-ALL initiation and survival.
TL;DR: Clinical and histopathological features of acantholytic-like amelanotic melanomas are defined and whether these tumors show characteristic driver mutations that overlap with those seen in SCC are delineated.
Abstract: Melanoma notoriously assumes a panoply of histopathologic appearances, many of which imitate other entities and represent a pitfall for diagnosticians. For example, some amelanotic melanomas with acantholytic-like features (acantholytic-like melanoma or melanoma with pseudo-acantholytic features) may mimic acantholytic squamous cell carcinoma (SCC), although this phenomenon is rarely reported and the underlying genetics are undefined. As clinicopathologic features often correlate with genomic alterations in common forms of melanoma, we sought to define clinical and histopathological features of acantholytic-like amelanotic melanomas and delineate whether these tumors show characteristic driver mutations that overlap with those seen in SCC.
TL;DR: The goal of the research program is to contribute to GC research in patients of Latino ancestry and advance cancer health disparity research, and generate a body of work that can be used for risk assessment, prevention, early diagnostic, and that will lead to better outcomes for GC in this important U.S. minority.
Abstract:
Gastric cancer (GC) disproportionally affects people of Latino ancestry and represent a leading cause of incidence and mortality disparities in this minority populations. When compared to Non-Latino Whites, Latinos are ~2-fold more likely to be diagnosed with and to die of GC. The goal of our research program is to contribute to GC research in patients of Latino ancestry and advance cancer health disparity research. One of the research projects aims at identifying germline variants associated with GC risk. To do so, we are identifying novel gastric cancer genes and detecting mutations in previously reported GC genes, using whole-exome sequencing, in 500 patients who have been diagnosed with early-onset GC and/or who had GC and family history of cancer. Whole exome sequence data collection was recently completed and is being analyzed with the primary goals of estimating the prevalence and penetrance in known cancer genes as well as the identification of new GC genes. Using in-house exome data and publicly available genetic data, we will identify variants with predicted impact in the phenotype to design a panel that will be used for their detection in gastric preneoplasia biopsies. These variants will be tested using duplex sequencing, a highly sensitive method that can detect very rare mutations with ultra-depth sequencing. We will then select the variants with likely functional consequences for tumor initiation and/or progression to generate isogenic gastric organoids to investigate their effect in proliferation, differentiation, and gene expression. We aim to generate a body of work that can be used for risk assessment, prevention, early diagnostic, and that will lead to better outcomes for GC in this important U.S. minority. Dr. Ana Estrada-Florez is the recipient of the AACR Cancer Health Disparities Fellowship.
Citation Format: Ana Patricia Estrada-Florez, Paul Lott, Ted Toal, Nicole Halmai, Elizabeth Quino, Alma Poceros-Coba, Alix Guevara, Fabian Castro, Jhon Suarez, John Mcpherson, Rasika Venkatesh, Hongyong Zhang, Apri Vang, Guadalupe Polanco, Joana Guerra, Graciela Molina, Carol Parra, Adriana Della Valle, Esteban Castelao, Manuel Teixeira, Mabel Bohorquez, Javier Torres, Alejandro Carvajal Corvalan, Luis G. Carvajal-Carmona. Identification of predisposition and progression gastric cancer biomarkers in Latinos [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2274.
TL;DR: In this article , the role of RAS pathway germline mutations in nevogenesis and melanomagenesis was evaluated by studying individuals with RASopathies, specifically cardio-facio-cutaneous (CFC) syndrome and Costello syndrome (CS) patients.
TL;DR: In this paper , a case of SCALP syndrome was diagnosed in a male infant with the characteristic findings of sebaceous nevi, central nervous system malformations, aplasia cutis congenita, limbal dermoid, and giant congenital melanocytic nevi.
Abstract: We present a case of SCALP syndrome, which was diagnosed in a male infant with the characteristic findings of sebaceous nevi, central nervous system malformations, aplasia cutis congenita, limbal dermoid, and giant congenital melanocytic nevi, or pigmented nevi. We identified a germline compound heterozygous DOCK6 mutation and a somatic mosaic NRAS Q61R mutation in the giant congenital melanocytic nevus. This report will increase clinician awareness of SCALP syndrome and augment the literature in characterizing this rare syndrome, including its genetic background.