Absolute lung cancer risk increases among individuals with >15 quit-years: Analyses to inform the update of the American Cancer Society lung cancer screening guidelines

BACKGROUND

This report quantifies counteracting effects of quit-years and concomitant aging on lung cancer risk, especially on exceeding 15 quit-years, when the US Preventive Services Task Force (USPSTF) recommends curtailing lung-cancer screening.

METHODS

Cox models were fitted to estimate absolute lung cancer risk among Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial (PLCO) and National Lung Screening Trial (NLST) participants who ever smoked. Absolute lung cancer risk and gainable years of life from screening for individuals aged 50 to 80 in the US-representative National Health Interview Survey (NHIS) 2015-2018 who ever smoked were projected. Relaxing USPSTF recommendations to 20/25/30 quit-years versus augmenting USPSTF criteria with individuals whose estimated gain in life expectancy from screening exceeded 16.2 days according to the Life Years From Screening-CT (LYFS-CT) prediction model was compared.

RESULTS

Absolute lung cancer risk increased by 8.7%/year (95% CI, 7.7%-9.7%; p < .001) as individuals aged beyond 15 quit-years in the PLCO, with similar results in NHIS and NLST. For example, mean 5-year lung cancer risk for those aged 65 years with 15 quit-years = 1.47% (95% CI, 1.35%-1.59%) versus 1.76% (95% CI, 1.62%-1.90%) for those aged 70 years with 20 quit-years in the PLCO. Removing the quit-year criterion would make 4.9 million more people eligible and increase the proportion of preventable lung cancer deaths prevented (sensitivity) from 63.7% to 74.2%. Alternatively, augmentation using LYFS-CT would make 1.7 million more people eligible while increasing the lung cancer death sensitivity to 74.0%.

CONCLUSIONS

Because of aging, absolute lung cancer risk increases beyond 15 quit-years, which does not support exemption from screening or curtailing screening once it has been initiated. Compared with relaxing the USPSTF quit-year criterion, augmentation using LYFS-CT could prevent most of the deaths at substantially superior efficiency, while also preventing deaths among individuals who currently smoke with low intensity or long duration.

Methods for Using Race and Ethnicity in Prediction Models for Lung Cancer Screening Eligibility

Importance

Using race and ethnicity in clinical prediction models can reduce or inadvertently increase racial and ethnic disparities in medical decisions.

Objective

To compare eligibility for lung cancer screening in a contemporary representative US population by refitting the life-years gained from screening-computed tomography (LYFS-CT) model to exclude race and ethnicity vs a counterfactual eligibility approach that recalculates life expectancy for racial and ethnic minority individuals using the same covariates but substitutes White race and uses the higher predicted life expectancy, ensuring that historically underserved groups are not penalized.

Design, Setting, and Participants

The 2 submodels composing LYFS-CT NoRace were refit and externally validated without race and ethnicity: the lung cancer death submodel in participants of a large clinical trial (recruited 1993-2001; followed up until December 31, 2009) who ever smoked (n = 39 180) and the all-cause mortality submodel in the National Health Interview Survey (NHIS) 1997-2001 participants aged 40 to 80 years who ever smoked (n = 74 842, followed up until December 31, 2006). Screening eligibility was examined in NHIS 2015-2018 participants aged 50 to 80 years who ever smoked. Data were analyzed from June 2021 to September 2022.

Exposure

Including and removing race and ethnicity (African American, Asian American, Hispanic American, White) in each LYFS-CT submodel.

Main Outcomes and Measures

By race and ethnicity: calibration of the LYFS-CT NoRace model and the counterfactual approach (ratio of expected to observed [E/O] outcomes), US individuals eligible for screening, predicted days of life gained from screening by LYFS-CT.

Results

The NHIS 2015-2018 included 25 601 individuals aged 50 to 80 years who ever smoked (2769 African American, 649 Asian American, 1855 Hispanic American, and 20 328 White individuals). Removing race and ethnicity from the submodels underestimated lung cancer death risk (expected/observed [E/O], 0.72; 95% CI, 0.52-1.00) and all-cause mortality (E/O, 0.90; 95% CI, 0.86-0.94) in African American individuals. It also overestimated mortality in Hispanic American (E/O, 1.08, 95% CI, 1.00-1.16) and Asian American individuals (E/O, 1.14, 95% CI, 1.01-1.30). Consequently, the LYFS-CT NoRace model increased Hispanic American and Asian American eligibility by 108% and 73%, respectively, while reducing African American eligibility by 39%. Using LYFS-CT with the counterfactual all-cause mortality model better maintained calibration across groups and increased African American eligibility by 13% without reducing eligibility for Hispanic American and Asian American individuals.

Conclusions and Relevance

In this study, removing race and ethnicity miscalibrated LYFS-CT submodels and substantially reduced African American eligibility for lung cancer screening. Under counterfactual eligibility, no one became ineligible, and African American eligibility increased, demonstrating the potential for maintaining model accuracy while reducing disparities.

Gender data gap in military research: a review of the participation of men and women in military musculoskeletal injury studies

Servicewomen are at increased risk of musculoskeletal injuries compared with their male counterparts, but women are under-represented in sports medicine research. The aim of this review was to assess the representation of women in military musculoskeletal injury studies. PubMed was searched for human original research studies using the terms Military OR Army OR Navy OR 'Air Force' AND 'musculoskeletal injury' Each study was categorised as epidemiology (basic training), epidemiology (trained personnel), risk factors, interventions and other. The number of male and female participants was retrieved from each study. A total of 262 studies were included: 98 (37%) studies only included men, 17 (6%) studies only included women and 147 (56%) studies included both men and women. A total of 8 051 778 participants were included in these studies (men: 6 711 082, 83%; women: 1 340 696, 17%). The study theme with the greatest proportion of women was musculoskeletal injury epidemiology studies in a basic training population (20% of participants) with the lowest proportion of women in intervention trials (6% of participants). These data suggest women are not under-represented in military musculoskeletal injury studies when considering the gender representation of most militaries. Our data are, however, biased by large epidemiological trials and women were under-represented in intervention trials. The under-representation of women in intervention trials could be due to difficulties in controlling for the effects of female sex steroids on musculoskeletal outcomes, or a focus on interventions in the most arduous military roles where injury risk is highest and women have been previously excluded.

Abstract 2950: Coexpression networks of miRNAs and gene transcripts coinciding with lung adenocarcinoma progression and survival

Lung & bronchus cancer is the second most diagnosed cancer, causing the most cancer-related deaths in the United States. A lung and bronchus subtype, NSCLC (non-small cell lung cancer), accounts for over 75% of new lung cancer diagnoses of which lung adenocarcinoma (LUAD) is the most common. Here, we studied the role of microRNAs and the transcriptome expression profile in LUAD prognosis, progression, and overall patient survival. We analyzed RNA-sequence data from a cohort of LUAD patients from The Cancer Genome Atlas (TCGA). The correlations of microRNA gene expression to transcription networks identified by weighted gene co-expression network analysis (WGCNA) were further explored in an upstream regulator/signaling pathway analysis, gene ontology (GO) process enrichment, and differential expression analysis. Mature microRNA abundance was also integrated with the mRNA network via correlation analysis. Our analysis revealed 18 clusters (modules) of highly correlated gene transcripts. The turquoise and red modules were of particular interest, as they were correlated negatively with overall survival, positively with stage 1 status, and negatively to later pathologic stages (3-4). Additionally, high select miRNA correlation to the red module transcripts (e.g., C16Orf89, ADGRF5, CFAP221, and SELENBP1; all with module eigengene correlation rho ≥ 0.75), and to the turquoise module (e.g., DDX39B and LENG8; each with rho ≥ 0.85) suggests these are miRNA-mRNA coregulatory networks of which both the gene products and potentially upstream miRNAs may serve as promising mechanistic targets and prognostic markers for LUAD, meriting further study.

Citation Format: Corey D. Young, Eric B. Dammer, Ti'ara L. Griffen, Sha'kayla K. Nunez, Courtney Dill, Kaylin M. Carey, James W. Lillard. Coexpression networks of miRNAs and gene transcripts coinciding with lung adenocarcinoma progression and survival [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 2950.

Abstract PR-13: Potential effect on racial/ethnic disparities of removing racial/ethnic variables from risk models: The example of lung-cancer screening

Background: Some uses of “race correction” in clinical algorithms and prediction models unfairly reduce access to care, resulting in calls to remove racial/ethnic variables from all models and algorithms. However, for models that are based on unbiased, high-quality, and plentiful data, removing racial/ethnic variables may reduce prediction accuracy for minorities. We model racial/ethnic disparities in screening eligibility from augmenting USPSTF-2021 guidelines (ages 50-80, ≥20 pack-years, ≤15 quit-years) to also include individuals selected by an NCCN-recommended risk model that includes race (PLCOM2012) versus the same model with race/ethnicity removed (PLCOM2012_NoRace). Methods: We used previously published methodology to model the performance of lung cancer screening using 6915 ever-smokers ages 50-80 from the US-representative 2015 National Health Interview Survey (NHIS). Individuals were considered eligible for screening if they are eligible by USPSTF-2021 guidelines or by PLCOM2012 (“USPSTF+PLCOM2012”), versus being eligible by USPSTF-2021 or PLCOM2012_NoRace (“USPSTF+PLCOM2012_NoRace”). Both models used the NCCN-recommended ≥1.3% 6-year risk-threshold for eligibility. We evaluated model accuracy (average percent over/under-estimation) by race/ethnicity, estimated the proportion of life-years gainable achieved by each eligible cohort (LYG), and evaluated the LYG disparity (difference in LYG between whites and each minority). Results: USPSTF+PLCOM2012 and USPSTF+PLCOM2012_NoRace identified similar numbers of minorities as eligible for screening (~2.7 million). However, USPSTF+PLCOM2012_NoRace selected 125% more Hispanic-Americans and 31% less African-Americans. LYG disparities decreased using USPSTF+PLCOM2012_NoRace versus USPSTF+PLCOM2012 for Hispanic Americans (LYG: 33% to 29%). However, LYG disparities for African Americans increased (LYG: 16% to 18%). PLCOM2012 underestimated lung cancer risk by 49% for Hispanic-Americans, whereas PLCOM2012_NoRace performed well (4% overestimation). However, PLCOM2012underestimated risk in African-Americans by only 6%, PLCOM2012_NoRace underestimated risk in African-Americans by 36%. Conclusion: The model that was most accurate for a minority group was projected to reduce disparities the most for that group. Removing race from the PLCOM2012 model substantially underestimated risk for African-Americans and may increase disparities. Inexplicably, PLCOM2012 substantially underestimated risk in Hispanic-Americans despite including race/ethnicity, which was alleviated by removing race/ethnicity. Great care must be taken when removing racial/ethnic variables from models, because this will assign minorities risk estimates that may be largely, or entirely, based on the majority population.

Citation Format: Corey D. Young, Li C. Cheung, Christine D. Berg, Patricia Rivera, Hilary A. Robbins, Anil K. Chaturvedi, Hormuzd A. Katki, Rebecca Landy. Potential effect on racial/ethnic disparities of removing racial/ethnic variables from risk models: The example of lung-cancer screening [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PR-13.

Identification of Gene Co-Expression Networks Associated with Consensus Molecular Subtype-1 of Colorectal Cancer

Simple Summary

Colorectal cancer (CRC) is a frequently lethal disease with heterogenous outcomes. Alterations in the Wnt signaling pathways have been shown to promote activation of signaling pathways such as MAPK and PI3K-Akt. Consensus molecular subtyping (CMS) provides a cohesive structure to classify the heterogeneity of CRC using gene expression analysis. CMS is categorized into four subtypes: CMS1, immune; CMS2, canonical; CMS3, metabolic; and CMS4, mesenchymal. Here, we identify co-expressed gene networks associated with CMS1. Our findings distinguish co-expressed gene networks that play a pivotal role in key features specific for CMS1, such as immune infiltration and activation. The co-expressed gene networks for CMS1 were significantly and positively correlated with the TNF, WNT, and ERK1 and ERK2 signaling pathways. This study highlights the relevance of CMS1 gene networks relating to oncogenic signaling cascades, cell activation, and positive regulation of immune responses, promoting CRC progressiveness.

Abstract

Colorectal cancer (CRC) is driven in part by dysregulated Wnt, Ras-Raf-MAPK, TGF-β, and PI3K-Akt signaling. The progression of CRC is also promoted by molecular alterations and heterogeneous—yet interconnected—gene mutations, chromosomal instability, transcriptomic subtypes, and immune signatures. Genomic alterations of CRC progression lead to changes in RNA expression, which support CRC metastasis. An RNA-based classification system used for CRC, known as consensus molecular subtyping (CMS), has four classes. CMS1 has the lowest survival after relapse of the four CRC CMS phenotypes. Here, we identify gene signatures and associated coding mRNAs that are co-expressed during CMS1 CRC progression. Using RNA-seq data from CRC primary tumor samples, acquired from The Cancer Genome Atlas (TCGA), we identified co-expression gene networks significantly correlated with CMS1 CRC progression. CXCL13, CXCR5, IL10, PIK3R5, PIK3AP1, CCL19, and other co-expressed genes were identified to be positively correlated with CMS1. The co-expressed eigengene networks for CMS1 were significantly and positively correlated with the TNF, WNT, and ERK1 and ERK2 signaling pathways, which together promote cell proliferation and survival. This network was also aligned with biological characteristics of CMS1 CRC, being positively correlated to right-sided tumors, microsatellite instability, chemokine-mediated signaling pathways, and immune responses. CMS1 also differentially expressed genes involved in PI3K-Akt signaling. Our findings reveal CRC gene networks related to oncogenic signaling cascades, cell activation, and positive regulation of immune responses distinguishing CMS1 from other CRC subtypes.

Using Prediction Models to Reduce Persistent Racial and Ethnic Disparities in the Draft 2020 USPSTF Lung Cancer Screening Guidelines

We examined whether draft 2020 United States Preventive Services Task Force (USPSTF) lung cancer screening recommendations "partially ameliorate racial disparities in screening eligibility" compared with the 2013 guidelines, as claimed. Using data from the 2015 National Health Interview Survey, USPSTF-2020 increased eligibility by similar proportions for minorities (97.1%) and Whites (78.3%). Contrary to the intent of USPSTF-2020, the relative disparity (differences in percentages of model-estimated gainable life-years from National Lung Screening Trial-like screening by eligible Whites vs minorities) actually increased from USPSTF-2013 to USPSTF-2020 (African Americans: 48.3%-33.4% = 15.0% to 64.5%-48.5% = 16.0%; Asian Americans: 48.3%-35.6% = 12.7% to 64.5%-45.2% = 19.3%; Hispanic Americans: 48.3%-24.8% = 23.5% to 64.5%-37.0% = 27.5%). However, augmenting USPSTF-2020 with high-benefit individuals selected by the Life-Years From Screening with Computed Tomography (LYFS-CT) model nearly eliminated disparities for African Americans (76.8%-75.5% = 1.2%) and improved screening efficiency for Asian and Hispanic Americans, although disparities were reduced only slightly (Hispanic Americans) or unchanged (Asian Americans). The draft USPSTF-2020 guidelines increased the number of eligible minorities vs USPSTF-2013 but may inadvertently increase racial and ethnic disparities. LYFS-CT could reduce disparities in screening eligibility by identifying ineligible people with high predicted benefit regardless of race and ethnicity.

Multivariate transcriptome analysis identifies networks and key drivers of chronic lymphocytic leukemia relapse risk and patient survival

Background

Chronic lymphocytic leukemia (CLL) is an indolent heme malignancy characterized by the accumulation of CD5⁺ CD19⁺ B cells and episodes of relapse. The biological signaling that influence episodes of relapse in CLL are not fully described. Here, we identify gene networks associated with CLL relapse and survival risk.

Methods

Networks were investigated by using a novel weighted gene network co-expression analysis method and examining overrepresentation of upstream regulators and signaling pathways within co-expressed transcriptome modules across clinically annotated transcriptomes from CLL patients (N = 203). Gene Ontology analysis was used to identify biological functions overrepresented in each module. Differential Expression of modules and individual genes was assessed using an ANOVA (Binet Stage A and B relapsed patients) or T-test (SF3B1 mutations). The clinical relevance of biomarker candidates was evaluated using log-rank Kaplan Meier (survival and relapse interval) and ROC tests.

Results

Eight distinct modules (M2, M3, M4, M7, M9, M10, M11, M13) were significantly correlated with relapse and differentially expressed between relapsed and non-relapsed Binet Stage A CLL patients. The biological functions of modules positively correlated with relapse were carbohydrate and mRNA metabolism, whereas negatively correlated modules to relapse were protein translation associated. Additionally, M1, M3, M7, and M13 modules negatively correlated with overall survival. CLL biomarkers BTK, BCL2, and TP53 were co-expressed, while unmutated IGHV biomarker ZAP70 and cell survival-associated NOTCH1 were co-expressed in modules positively correlated with relapse and negatively correlated with survival days.

Conclusions

This study provides novel insights into CLL relapse biology and pathways associated with known and novel biomarkers for relapse and overall survival. The modules associated with relapse and overall survival represented both known and novel pathways associated with CLL pathogenesis and can be a resource for the CLL research community. The hub genes of these modules, e.g., ARHGAP27P2, C1S, CASC2, CLEC3B, CRY1, CXCR5, FUT5, MID1IP1, and URAHP, can be studied further as new therapeutic targets or clinical markers to predict CLL patient outcomes.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12920-021-01012-y.

Abstract PO-247: Use of prediction models to reduce racial/ethnic disparities in eligibility for lung-cancer screening

Background: For the same age and smoking history as whites, minorities have substantially different lung-cancer risk. However, current US Preventive Services Task Force (USPSTF) lung-cancer screening recommendations make no allowance for race/ethnicity and may induce health disparities. Incorporating individualized prediction-models into USPSTF guidelines may reduce racial/ethnic disparities in lung-cancer screening eligibility. We examine whether expanding current USPSTF lung cancer screening eligibility to include ever-smokers whose risk (calculated by an individualized prediction model) exceeded a threshold would reduce racial/ethnic disparities induced by current USPSTF guidelines. Methods: We used the US- representative 2015 National Health Interview Survey to examine screening eligibility. We identified the thresholds for each of 5 models: lung-cancer risk (Bach, PLCOM2012 and LCRAT models), lung-cancer death risk (LCDRAT model), and life- years gained by attending screening (LYFS-CT model), which select the same number of ever-smokers aged 50-80yrs as USPSTF guidelines. We defined 5 cohorts of ever- smokers as eligible for screening if they were eligible by each screening model or USPSTF guidelines. Among each race/ethnicity, we calculated the number eligible for screening, proportion of preventable lung-cancer deaths prevented (LCD sensitivity), proportion of gainable life-years gained (LYG sensitivity) and screening effectiveness (the number needed to screen to prevent one lung-cancer death). Results: USPSTF criteria performed best for whites (20% eligible, preventing 55% of preventable lung- cancer deaths). Asian-Americans had the least effective screening (NNS=419), only 13% of African-Americans were eligible despite having the most effective screening (NNS=135), and Hispanic-Americans had the lowest percentages eligible (9%) and deaths preventable (30%). Augmenting USPSTF criteria with LCDRAT or LYFS-CT prediction-models nearly equalized the performance of screening for African- Americans with that of whites, doubling the number of African-Americans eligible and increasing the number of preventable deaths and life-years gained by nearly 80%, although at a 25% loss in effectiveness. Prediction-models improved all screening metrics for Asian-Americans and Hispanic-Americans. However models estimated risk more accurately for whites than minorities. Conclusions: Augmenting USPSTF criteria with the LCDRAT or LYFS-CT prediction-models nearly eliminated the white/African-American disparity. All screening metrics were substantially improved for Asian/Hispanic-Americans.

Citation Format: Rebecca Landy, Corey D. Young, Martin Skarzynski, Li C. Cheung, Christine D. Berg, M. Patricia Rivera, Hilary A. Robbins, Anil K. Chaturvedi, Hormuzd A. Katki. Use of prediction models to reduce racial/ethnic disparities in eligibility for lung-cancer screening [abstract]. In: Proceedings of the AACR Virtual Conference: Thirteenth AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2020 Oct 2-4. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(12 Suppl):Abstract nr PO-247.

WGCNA identification of CXCL13 and associated genes involved in the Tumor Immune Microenvironment (TIME) of lung adenocarcinoma

Lung cancer is the second most commonly diagnosed cancer, causing the most cancer-related deaths in the United States. Non-small cell lung cancer (NSCLC) accounts for over 75% of lung cancer cases of which lung adenocarcinoma (LUAD) is the most common. Chemokines and their receptors have been shown to be highly expressed in a number of cancers, presumably leading to abnormal signaling. Elevated levels of CXCL13, and its receptor, CXCR5, have been correlated with the overall features of mortality, but the exact mechanisms in which these factors act to promote NSCLC progression are not fully understood. Here, we studied the role of CXCL13, CXCR5, and associated genes expressed in NSCLC tumor immune microenvironment (TIME). The software package WGCNA was used to establish clusters of highly correlated genes related to clinical characteristics. A total of 23,329 transcripts were used to identify 37 modules (gene co-expression networks). The light-cyan module, consisting of 491 genes contained both CXCR5 and CXCL13. The light-cyan module is a hub gene heavy module with the top 300 transcripts exceeding our hub gene threshold (kMe &gt; 0.6). The light-cyan module transcripts where negatively correlated with age. The top biological processes associated with the light-cyan module include immune system processes, regulation of lymphocyte activation, regulation of immune response and cellular defense response. Collectively, the gene clusters identified along with their clinical correlates provide a novel insight into the complex biology of NSCLC and its TIME.

Transcriptome network analysis identifies co-expressed CXCL13, CXCR5, and associated genes contributes to the aggressive phenotype of TNBC

Triple negative breast cancer (TNBC) is an aggressive disease associated with poor prognosis. Currently, there are no targeted therapies for this disease. Standard therapy for TNBC consists of a combination of chemotherapeutic drugs. However, patients often become resistant to this intervention and ultimately succumb to this disease. Hence, understanding the cellular and molecular mechanisms associated with TNBC progression is essential to develop more effective therapies. We hypothesize co-expressed CXCL13, CXCR5, and associated genes are significantly correlated with TNBC and poor overall survival. A bioinformatic approach was used to characterize this new potential drug target for TNBC. Our patient cohort was obtained from The Cancer Genome Atlas. Weighted gene network co-expression analysis identified gene networks associated with factors influencing BrCa prognosis. An ANOVA test identified genes differentially expressed among Luminal A, Luminal B, HER-2, and TNBC tumor groups. Finally, gene ontology analysis was performed via GO-ELITE and EPIC was used to estimate the proportion of various cell types found in bulk samples. We identified seven unique gene networks that were significantly and positively correlated with TNBC. The turquoise module (M1), contained CXCL13, CXCR5, and associated genes that drive tertiary lymphoid structure formation, regulation of immune response, and immune system processes. The M1 module was also significantly and positively correlated with TNBC, but not overall survival. The genes signatures contained in the M1 module were significantly correlated to CD8+ T cell, macrophage, B cell, CD4+ T cell, cancer-associated fibroblast, and NK cell, as determined by EPIC analysis.

Multivariate Gene Expression Analysis Identifies Novel Signatures and Therapeutic Targets for CLL Relapse

Chronic Lymphocytic Leukemia (CLL) is a hematological malignancy of immature B cells that is characterized by episodes of relapse. CLL relapse is supported by pro-survival factors, such as chemokines, secreted CLL cells of the CLL microenvironment. The CXCL13-CXCR5 axis has been previously shown to contribute to the progression of several malignancies and possibly CLL relapse. CXCR5 is highly expressed by CLL cells and CXCL13 serum levels were found to be significantly higher in CLL patients versus healthy donors. There is a gap in the understanding of the molecular mechanisms following CXCL13-CXCR5 interactions during CLL. The presence of CXCR5, CXCL13, and associated genes were investigated by using a novel weighted gene co-expression network analysis (WGCNA) method as well as examining overrepresentation of upstream regulators and biological functions found in the transcriptomes (24,658 genes) of CLL patients (n = 203). The WGCNA-designated yellow (p = 0.003), brown (p = 0.05), purple (p &lt; 0.001), black (p = 0.006), and salmon (p = 0.001) modules were significantly correlated with relapse. The fourth-largest, yellow co-expression module contained CXCR5 and 1,315 other genes. The biological processes associated with this module included lipid metabolism, protein catabolism, positive regulation of cell cycle arrest, and cell cycle checkpoint signal transduction. Systems pharmacology analysis revealed drugs targeting ATPases, proteasomes, and microtubules, could disrupt CLL relapse signatures, found in the yellow module. Taken together, the relapse associated gene networks have provided new insights on the complex biology of CLL and identified new targets for the treatment CLL relpase.

CXCL13-CXCR5 signaling and its co-expression network are associated with colorectal cancer cell growth and poor prognosis

The heterogeneity of colorectal cancer (CRC) and its microenvironment has molecular traits of immune cells, and is driven by dysregulated WNT, RAS-RAF-MAPK, TGF-β, and PI3K-AKT pathways. CXCL13-CXCR5 signaling has been shown to induce PI3K- and Ras-dependent activation of MAPK/ERK1-2 to promote cancer cell survival, invasion, and growth. The hypothesis tested in this study is CXCL13-CXCR5 signaling and co-expression networks mediate CRC progression, cell growth, and survival. RNAseq data from CRC cases, along with matched controls, were acquired from The Cancer Genome Atlas (TCGA). Weighted gene co-expression network analysis (WGCNA) elucidated gene networks that significantly correlated with CRC poor prognosis. CXCL13, CXCR5, and other co-expressed genes were identified in the WGCNA designated brown module (M3). The canonical pathways and their upstream regulators of this module were analyzed using Ingenuity Pathway Analysis (IPA). M3 hub genes XCL1, CCL19, PIK3AP1, FLT3, and WNT1 were significantly and positively correlated with PI3K, WNT, ERK1 and ERK2 activation, which promotes cell proliferation and survival. Next, we measured the CRC cell line growth effected by CXCL13 using a XTT assay. In confirmation, CXCL13 treatment of CRC cell lines significantly increased CRC cell line proliferation, but had no direct influence on cell survival. Our findings strongly support CXCL13-CXCR5 signaling and its co-expression networks activates important pathways associated with CRC progression and tumor growth.

Macrophages Promote Growth of Squamous Cancer Independent of T cells

Oral cancers, primarily squamous cell carcinomas (SCCs), progress either slowly or aggressively. Here we assessed the role of macrophages in SCC behavior. We used mouse SCC cells derived from tumors harboring a Kras^G12D activation mutation and Smad4 deletion in keratin 15-positive stem cells and a human oral SCC cell line, FaDu, which has NRAS amplification and SMAD4 deletion. SCC cells were transplanted into immune-compromised or immune-competent (syngeneic) recipients. After tumors were established, we used clodronate liposomes to ablate macrophages. We found that the number of tumor-associated macrophages (TAMs) was not affected by the presence of T cells but differed considerably among tumors derived from different SCC lines. Clodronate significantly reduced TAMs and splenic macrophages, resulting in reduced SCC volumes. Tumors with clodronate treatment did not show decreased proliferation but did exhibit increased apoptosis and reduced vascular density. FLIP (Fas-associated via death domain-like interleukin 1β-converting enzyme inhibitory protein), an apoptosis inhibitor abundantly produced in tumor cells and TAMs, was reduced in tumor cells of clodronate-treated mice. Reduced FLIP levels correlated with reductions in phosphorylated nuclear NFκB p65 and NFκB inhibitor attenuated FLIP protein levels in SCC cells. Furthermore, TGFβ1 serum levels and pSmad3 were reduced in clodronate-treated mice, but their reductions were insufficient to reverse epithelial-mesenchymal transition or TGFβ-mediated angiogenesis in endothelial cells. Consequently, metastasis was not significantly reduced by macrophage reduction. However, reduced pSmad3 correlated with reduction of its transcriptional target, vascular endothelial growth factor A, in clodronate-treated tumor cells, which correlated with reduced vascular density in clodronate-treated tumors. Taken together, our study revealed that macrophages contribute to SCC expansion through interactions with tumor cells but are dispensable for SCC metastasis. Our study provides novel insights into understanding the contributions and limitations of TAMs in SCC progression.

Weighted Gene Co-expression Network Analysis of CXCL13, CXCR5, and associated genes in multiple myeloma

Multiple myeloma (MM) is characterized by the neoplastic proliferation of plasma cells. In 2018, there were approximately 30,770 new cases diagnosed and about 12,770 dead. Characterizing its molecular phenotypes is important for effective treatment of MM and predicting relapse. CXCL13-CXCR5 interactions are involved in malignancy cell homing, adhesion, signal transduction, and calcium flux, all of which promote MM progression. Here, we analyzed RNA-sequence data from matched normal, primary and relapsed MM cases. Patient control mRNA samples matched primary tumor and relapse samples were acquired from the database of Genotypes and Phenotypes to evaluate the mRNA expression patterns of CXCL13, CXCR5 and associated genes in MM. Bioinformatics tools were to integrate published genomic data from MM patients (n=480) and identify genes associated with CXCL13-CXCR5 signaling. DESeq analysis was used to determine differentially expressed genes between normal tissues, primary tumor, and relapse groups. Weighted gene co-expression network analysis identified clusters of genes significantly associated with the molecular phenotypes of MM. Notably, gene expression is driven by NFAT and JUN, known to be activated by the CXCL13-CXCR5 axis, and plasma cell signaling pathways significantly correlated with select MM molecular phenotypes and patient survival. Ingenuity pathway analysis was performed to analyze upstream regulators, gene interaction and canonical pathways. Taken together, our data show CXCR5-CXCL13 signaling networks are significantly expressed and associated with MM pathogenesis and plasma clonality. This study provides a better understanding of the heterogeneous nature of MM and the role of CXCL13-CXCR5 axis in MM.

Weighted Gene Correlation Network Analysis of Ovarian Cancer Driven by CXCL13- CXCR5 Interactions

Ovarian Cancer (OvCa) is a disease that affects postmenopausal women, with high-grade serous ovarian carcinoma being the most common and lethal type. Many patients are asymptomatic in the early stages of OvCa, thus going undetected, leading to higher patient mortality rates. Identifying biomarkers involved in ovarian cancer progression could enhance current therapeutic outcomes. Our laboratory was the first to show that CXCL13- CXCR5 signaling mediates prostate, breast and lung cancer cell growth, migration, invasion, and survival. We provided evidence that these chemokines are highly elevated in OvCa cell lines and clinical samples. These previous findings provided the rationale to support the hypothesis CXCL13-CXCR5 signaling promotes OvCa progression, metastasis and survival. In this study, we analyzed transcriptome data to determine possible molecular mechanisms and CXCL13-CXCR5 signaling pathways controlling OvCa progression. Weighted Gene Network Co-expression (WGCNA) analysis and Ingenuity Pathway Analysis were used to identify gene coexpression networks correlated with aggressive OvCa clinical phenotypes. CXCR5 was found to be co-expressed with several genes such as RB1, PIK3C3, GNAI1, LTB TNFRSF11B which are known to facilitate OvCa progression and tertiary lymphoid structure formation. Upon further analysis, we found that these gene expressions closely correlated with age at diagnosis and patient relapse. Our study suggests an important role of CXCL13-CXCR5 signaling and reveals an important set of co-expressed epigengenes involved in OvCa relapse.

Mouse Models for Studying Oral Cancer: Impact in the Era of Cancer Immunotherapy

Model systems for oral cancer research have progressed from tumor epithelial cell cultures to in vivo systems that mimic oral cancer genetics, pathological characteristics, and tumor-stroma interactions of oral cancer patients. In the era of cancer immunotherapy, it is imperative to use model systems to test oral cancer prevention and therapeutic interventions in the presence of an immune system and to discover mechanisms of stromal contributions to oral cancer carcinogenesis. Here, we review in vivo mouse model systems commonly used for studying oral cancer and discuss the impact these models are having in advancing basic mechanisms, chemoprevention, and therapeutic intervention of oral cancer while highlighting recent discoveries concerning the role of immune cells in oral cancer. Improvements to in vivo model systems that highly recapitulate human oral cancer hold the key to identifying features of oral cancer initiation, progression, and invasion as well as molecular and cellular targets for prevention, therapeutic response, and immunotherapy development.

Abstract P6-12-09: Pan-HER, an antibody mixture with antitumor activity against drug-resistant HER2-overexpressing breast cancers with high ERBB ligand expression

Background: Amplification/overexpression of ERBB receptors and/or ligands has been associated with resistance to anti-HER2 therapies. Pan-HER is a mixture of six antibodies targeting each of the ERBB receptors, EGFR, HER2 and HER3, with synergistic pairs of antibodies. Each pair of antibodies simultaneously blocks ligand binding and/or induces target degradation, thus preventing compensatory mechanisms to anti-ERBB therapies. We examined the antitumor activity of Pan-HER against drug-sensitive and -resistant HER2+ breast cancer cells and xenografts.

Results: Pan-HER exhibited potent growth inhibitory activity against a panel of HER2+ breast cancer cells (BT474, MDA-453, MDA-361, SUM190, HCC1954, UACC893 and SKBR3). Growth inhibition was associated with internalization and degradation of EGFR, HER2 and HER3. Pan-HER was superior to the combination of trastuzumab/pertuzumab (TP) against HER2+/PIK3CA mutant MDA-361, HCC1954, UACC893 and MDA-453 cells. We next compared the effect of Pan-HER against BT474, HCC1954 and MDA-361 xenografts established in nude mice to that of trastuzumab/lapatinib (TL), TP and T-DM1. All treatments were effective across the panel of xenografts. In mice with MDA-361 tumors, Pan-HER and TP were superior to TL. Immunoblot analysis showed significant downregulation of EGFR, HER2 and HER3 only in tumors treated with Pan-HER. After a complete response, treatment was discontinued. Among mice with BT474 xenografts treated with TP, TL and T-DM1, 25-50% of mice exhibited a tumor recurrence within 50 weeks of follow-up, while no recurrences were registered in mice treated with Pan-HER. Tumors recurring after TP and T-DM1 expressed significantly higher HER3 and P-HER3 protein levels and NRG1 mRNA levels. HCC1954 xenografts recurring after T-DM1 also overexpressed NRG1 mRNA compared to tumors before therapy.

We next examined the effect of Pan-HER against trastuzumab-resistant HR6 (BT474) cells (Ritter et al. CCR 2007) and HCC1954 and UACC893 cells with acquired resistance to T-DM1 (TDR; IC50 &gt;5-, &gt;6- and 600-fold in HR6, UACC893-TDR and HCC1954-TDR cells, respectively, vs. parental cells). All T-DM1-resistant cells expressed significantly higher HER3 and P-HER3 protein levels and NRG1 mRNA and protein levels. Treatment with the HER3 neutralizing antibody LJM716 resensitized HR6 and HCC1954-TDR cells to T-DM1, suggesting a causal association between the NRG1-HER3 axis and drug resistance. Mice with HR6 tumors were treated with Pan-HER, TL, TP and T-DM1. Only Pan-HER arrested HR6 tumor growth and downregulated EGFR, HER2, HER3, P-HER3 and P-AKT. Finally, HCC1954-TDR tumors rapidly grew in vivo despite treatment with T-DM1. Administration of Pan-HER to mice bearing HCC1954-TDR xenografts growing in the presence of T-DM1, induced rapid tumor regressions.

Conclusions: These data suggest that multitarget therapeutic interventions, such as Pan-HER, which simultaneously remove and/or block all ERBB receptors and ligands, are a feasible and effective approach against HER2-overexpressing cancers both sensitive and resistant to anti-HER2 therapies.

Citation Format: Schwarz LJ, Hutchinson KE, Estrada MV, Sanders ME, Dugger TC, Formisano L, Guerrero AL, Red-Brewer M, Young CD, Lantto J, Pedersen MW, Kragh M, Horak ID, Arteaga CL. Pan-HER, an antibody mixture with antitumor activity against drug-resistant HER2-overexpressing breast cancers with high ERBB ligand expression [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P6-12-09.

Abstract S3-03: Nuclear FGFR1 interaction with estrogen receptor (ER) α is associated with resistance to endocrine therapy in ER+/FGFR1-amplified breast cancer

Background: Estrogen receptor (ER)-positive breast cancers (BC) initially respond to antiestrogens but eventually become hormone-independent and recur. FGFR1 is amplified in ∼10% of ER+ BC and is associated with early recurrence on antiestrogen therapy. Notably, one third of FGFR1-amplified tumors have simultaneous amplification of CCND1, FGF3, FGF4 and FGF19 on chromosome 11q12-14. Herein, we investigated the mechanisms by which FGFR1 amplification confers resistance to antiestrogen therapy in ER+ BC cells.

Results: We performed whole exome sequencing in tumor biopsies from 130 patients with an operable ER+/HER2- BC who had received letrozole for 10-21 days prior to surgery. Tumors were categorized by the natural log (ln) of post-letrozole Ki67 as sensitive (ln ≤1 or ≤2.7% Ki67+ cells; n=68) or resistant (ln ≥2 or ≥7.4%; n=18). We found amplifications in FGFR1 and/or 11q12-14 in 6/11 (55%) resistant tumors compared with 5/34 (15%) in sensitive tumors (p=0.006); all cases were confirmed by FGFR1-fluorescence in situ hydridization (FISH). Resistant tumors with FGFR1 and/or 11q12-14-amplification showed a marked increase in nuclear FGFR1 with letrozole. ER+/FGFR1-amplified CAMA1 and MDA134 cell lines also exhibited co-localization of ER and FGFR1 in the nucleus. Cell proliferation was partially reduced by estrogen deprivation, and FGFR1 siRNA further reduced cell growth in hormone-depleted medium. We generated CAMA1 and MDA134 cells resistant to long-term estrogen deprivation (LTED). These cells exhibited overexpression of FGF3/4/19 and ERα with a concomitant increase in ligand-independent ER transcriptional activity and growth. An ER-FGFR1 interaction was observed in the nucleus and cytosol of CAMA1 parental cells with enhanced interaction in CAMA1 LTED cells. Genetic (with siRNA) and pharmacologic (with lucitinib) inhibition of FGFR1 reduced a) nuclear localization of FGFR1; b) ER transcriptional activity; and c) cell proliferation. Nuclear localization and ER-FGFR1 interaction were disrupted by a kinase-deficient FGFR1. Conversely, addition of FGF3 ligand stimulated ER-FGFR1 interaction and ER transcriptional activity, suggesting FGFR activation can regulate ER function. Inhibition of FGF receptor-specific substrate (FRS2), a principal mediator of FGFR1 signal transduction to the MAPK and PI3K pathways, with siRNA or pharmacologic inhibition of PI3K with buparlisib or MEK with GSK1120212 did not reduce ER transcriptional activity suggesting that, in ER+/FGFR1-amplified cancer cells, ER function is not modulated by FGFR signal transducers. Finally, using chromatin immunoprecipitation (ChIP) we showed that FGFR1 binds directly to estrogen response elements (ERE). This association was reduced with lucitanib. We are currently investigating genes modulated by ER/FGFR1 in ER+ BC and the in vivo anti-tumor efficacy of dual inhibition of FGFR1 and ER in ER+/FGFR1-amplified patient-derived breast cancer xenografts.

Conclusions: These data support a critical role of ER and FGFR1 interaction in endocrine resistance in ER+/FGFR1-amplified breast cancer. Targeting of FGFR1 in combination with antiestrogens may abrogate resistance to endocrine therapy in these tumors and is worthy of clinical investigation.

Citation Format: Formisano L, Young CD, Bhola NE, Bulen B, Estrada VM, Wagle N, Van Allen E, Red Brewer ML, Jansen VM, Guerrero AL, Giltnane JM, Strcker T, Arteaga CL. Nuclear FGFR1 interaction with estrogen receptor (ER) α is associated with resistance to endocrine therapy in ER+/FGFR1-amplified breast cancer. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr S3-03.

Extragenic suppressors of the nimX2(cdc2) mutation of Aspergillus nidulans affect nuclear division, septation and conidiation

The Aspergillus nidulans NIMX(CDC2) protein kinase has been shown to be required for both the G(2)/M and G(1)/S transitions, and recent evidence has implicated a role for NIMX(CDC2) in septation and conidiation. While much is understood of its G(2)/M function, little is known about the functions of NIMX(CDC2) during G(1)/S, septation, and conidiophore development. In an attempt to better understand how NIMX(CDC2) is involved in these processes, we have isolated four extragenic suppressors of the A. nidulans nimX2(cdc2) temperature-sensitive mutation. Mutation of these suppressor genes, designated snxA-snxD for suppressor of nimX, affects nuclear division, septation, and conidiation. The cold-sensitive snxA1 mutation leads to arrest of nuclear division during G(1) or early S. snxB1 causes hyperseptation in the hyphae and sensitivity to hydroxyurea, while snxC1 causes septation in the conidiophore stalk and aberrant conidiophore structure. snxD1 leads to slight septation defects and hydroxyurea sensitivity. The additional phenotypes that result from the suppressor mutations provide genetic evidence that NIMX(CDC2) affects septation and conidiation in addition to nuclear division, and cloning and biochemical analysis of these will allow a better understanding of the role of NIMX(CDC2) in these processes.

The distribution and origin of the calretinin-containing innervation of the nucleus accumbens of the rat

The nucleus accumbens of the rat consists of several subregions that can be distinguished on the basis of histochemical markers. For example, the calcium-binding protein calbindin D28k is a useful marker of the core compartment of the nucleus accumbens. Calretinin, another calcium-binding protein, is found in a dense fibre plexus in the accumbal shell and septal pole regions. The source of the accumbal calretinin innervation is not known. We examined the distribution of calretinin in the nucleus accumbens and used tract-tracing and lesion methods to determine the source of this calretinin innervation. Intense calretinin immunoreactivity was present in the medial shell, but the density of calretinin axons diminished sharply in the ventrolateral shell. Regions of dense calretinin immunostaining and those areas with calbindin-like immunoreactive cell bodies were generally segregated in the nucleus accumbens, although some overlap in the transition region between the core and shell was seen. Small clusters of calretinin-immunoreactive fibres were seen in the core, where they were restricted to calbindin-negative patches. Injections of the anterograde tracer biotinylated dextran amine into the paraventricular thalamic nucleus labelled fibres in calretinin-rich regions of the accumbens. Conversely, injections of Fluoro-gold into the accumbal shell retrogradely labelled numerous cells in the paraventricular thalamic nucleus that were calretinin-immunoreactive. Electrolytic lesions of the paraventricular thalamic nucleus reduced calretinin levels in the shell by approximately 80%. These data indicate that the calretinin innervation of the nucleus accumbens is derived primarily from the thalamic paraventricular nucleus, and marks accumbal territories that are largely complementary to those defined by calbindin.

The impact of race on freedom from prostate-specific antigen failure in prostate cancer patients treated with definitive radiation therapy

Many studies have reported that African-American men have the highest incidence and mortality rates for prostate cancer in the United States. A retrospective analysis of 607 patients treated with definitive radiation therapy was performed at the University of California San Francisco and its affiliated hospitals between 1987 and 1995. The patient population analyzed included African-American, Caucasian, and Asian men with AJCC T1-T3 disease. Race, Gleason score, pretreatment prostate-specific antigen levels, stage, and treatment delivery were all evaluated. The percent free from PSA failure at 48 months for African-American, Caucasian, and Asian men were 53%, 59%, and 53%, respectively. There was no difference among the three races or for any of the pairwise comparisons. Gleason score and stage of disease were each independent predictors of outcome, but race was not associated with remaining free from PSA failure. These results are similar to those recently reported in the literature from centers of excellence across the United States.

Clozapine pretreatment modifies haloperidol-elicited forebrain Fos induction: a regionally-specific double dissociation

RATIONALE

Acute administration of typical antipsychotic drugs, such as haloperidol, results in the induction of the immediate-early gene c-fos in the dorsolateral striatum. In contrast, the atypical antipsychotic drug clozapine, which lacks significant extrapyramidal side effect liability, does not induce Fos protein in the dorsal striatum. Several studies have attempted to define the mechanisms through which typical antipsychotic drugs induce striatal Fos, often by pretreating animals with specific receptor antagonists. Despite the broad receptor profile of clozapine, there has been no study of the effect of clozapine pretreatment on haloperidol-elicited striatal Fos expression.

METHODS

We examined the effects of clozapine pretreatment of rats on haloperidol-elicited forebrain Fos expression, using both immunoblot and immunohistochemical methods. The effects of clozapine pretreatment were assessed in the dorsal striatum and in the different nucleus accumbens compartments, the septum, and the prefrontal cortex.

RESULTS

Clozapine pretreatment markedly decreased haloperidol-elicited striatal Fos induction and blocked haloperidol-induced catalepsy. Clozapine also attenuated haloperidol-elicited Fos expression in the nucleus accumbens, but in the prefrontal cortex and ventrolateral septum the effects of haloperidol and clozapine were additive.

CONCLUSIONS

An emerging body of literature suggests a high incidence of rapid relapse in schizophrenic patients when clozapine treatment is discontinued. This psychosis is relatively resistant to haloperidol and other neuroleptics, even in patients who had previously responded well to neuroleptics. The present data may shed light on the central sites associated with and perhaps model certain aspects of the relapse associated with clozapine discontinuation.

Psychostimulant-induced Fos protein expression in the thalamic paraventricular nucleus

Lesions of glutamatergic afferents to the nucleus accumbens have been reported to block psychostimulant-induced behavioral sensitization. However, thalamic glutamatergic projections to the nucleus accumbens have received little attention in the context of psychostimulant actions. We examined the effects of acute amphetamine and cocaine administration on expression of Fos protein in the thalamic paraventricular nucleus (PVT), which provides glutamatergic inputs to the nucleus accumbens and also receives dopaminergic afferents. Immunoblot and immunohistochemical studies revealed that both psychostimulants dose-dependently increased PVT Fos expression. PVT neurons retrogradely labeled from the nucleus accumbens were among the PVT cells that showed a Fos response to amphetamine. D2 family dopamine agonists, including low doses of the D3-preferring agonist 7-OH-DPAT, increased the numbers of Fos-like-immunoreactive neurons in the PVT. Conversely, the effects of cocaine and amphetamine on PVT Fos expression were blocked by pretreatment with the dopamine D2/3 antagonist raclopride. Because PVT neurons express D3 but not other dopamine receptor transcripts, it appears that psychostimulants induce Fos in PVT neurons through a D3 dopamine receptor. We suggest that the PVT may be an important part of an extended circuit subserving both the arousing properties and reinforcing aspects of psychostimulants.

High-strength, ultra-thin and fiber-reinforced pHEMA artificial skin

Membranes of pHEMA-based composites were manufactured by adding various kinds of weaved and knitted fabrics and fibers into a deionized water solution of HEMA monomer, EGDMA cross-linker and BIE initiator, and followed by polymerization under ultraviolet radiation. By varying the amount of initial water addition (IWA), the dimensional change of pHEMA matrix from the newly fabricated state to the eventually swollen state could be adjusted to reduce the swellability mismatch with the fabrics and the possibility of the swollen membranes becoming folded and curled was avoided. Mechanical properties of the fiber-reinforced pHEMA composites, including yielding strength, maximum strength, Young's modulus and elongation at break, are improved evidently depending on the mechanical characteristics of additives applied. The involvement of fabrics and fibers in the soft pHEMA matrix also provides an alternative of making the ultra-thin membranes to overcome the problem of easily being torn during handling. In addition, some of these membranes also exhibit an improvement in water transmission rate.

Effects of desmethylclozapine on Fos protein expression in the forebrain: in vivo biological activity of the clozapine metabolite

Several products of the hepatic metabolism of clozapine are found in high concentrations in the plasma of schizophrenic patients treated with this atypical antipsychotic drug. One of these metabolites, N-desmethylclozapine, has substantially different affinities for dopamine and serotonin metabolites than does the parent compound. However, it is not known if this metabolite is active in vivo. We examined the effect of acute administration of desmethylclozapine to rats on forebrain Fos protein expression. Clozapine induces expression of this immediate-early gene in a distinct regional pattern in the brain. Desmethylclozapine significantly increased Fos protein expression in the medial prefrontal cortex and nucleus accumbens, but not in the dorsolateral striatum, thus mirroring the effects of the parent compound. These data indicate that the desmethyl metabolite of clozapine has in vivo biological activity.

The effects of thalamic paraventricular nucleus lesions on cocaine-induced locomotor activity and sensitization

The brain circuitry that subserves the augmented locomotor response to repeated psychostimulant administration has been the subject of intense scrutiny. The dopaminergic innervation of the nucleus accumbens is critically involved in psychostimulant-elicited behavioral sensitization, and recent studies suggest that lesions of structures that send glutamatergic projections to the nucleus accumbens alter the acquisition or expression of psychostimulant-elicited sensitization. Although certain thalamic nuclei provide a major glutamatergic input to the striatum, the involvement of the thalamus in psychostimulant-elicited sensitization has not been investigated. We therefore examined the effects of lesions of the thalamic paraventricular nucleus, which projects to the shell of the nucleus accumbens, on cocaine-elicited locomotor sensitization. Lesions of the paraventricular nucleus did not alter basal locomotor activity, but significantly enhanced the acute locomotor response to cocaine. In contrast, repeated cocaine administration did not progressively augment locomotor activity in lesioned rats, but did so in sham-lesioned animals. The thalamic lesions also blocked the conditioned locomotor response to the environment in which the cocaine injections took place. These data suggest that the thalamic paraventricular nucleus may be an integral part of extended circuitry that subserves both the conditioned and nonconditioned components of psychostimulant-induced behavioral sensitization.

Simultaneous determination of amoxycillin and clavulanic acid in pharmaceutical products by HPLC with beta-cyclodextrin stationary phase

A simple, rapid and accurate method for simultaneous determination of amoxycillin and clavulanic acid using HPLC with beta-cyclodextrin stationary phase was developed. It involves the use of tetraethylammonium acetate (TEAA) as an additive reagent, methanol-buffer solution (pH 4.5) (35:65; v/v) as the mobile phase, detection at 225 mm and chromatogram within 12 min. Linearity and precision of the internal standard method have been obtained. Recoveries ranged from 99.25 to 105.63% for amoxycillin in the synthetic mixture. For clavulanic acid it was from 99.50 to 101.64%. This method is convenient and reproducible for analyses of these two components in different dosage forms.

Circadian rhythm in the visual system of the lizard Anolis carolinensis

The electroretinogram (ERG) was recorded from free-moving Anolis lizards once per hour for 5 days. As in our previous work, the b-wave, but not the a-wave, showed a reliable circadian rhythm (CR) in amplitude, with an acrophase near projected noon. Both the a- and b-waves showed a CR in peak time (implicit time, or IT), with the a-wave IT being longest near midnight, and the b-wave IT at midday. Acrophases were shifted when animals were housed on a phase-shifted light-dark cycle. The ERG CR was unaffected by removal of the parietal organ, but it was virtually abolished by removal of the pineal gland, thus suggesting that pineal output (probably melatonin) modulates retinal responses. In addition to the ERG, the tectal light-evoked potential exhibited a CR--a finding compatible with a circadian variation in retinal output. Lastly, the amplitude of the ERG component waveforms showed a seasonal variation, but the ERG CR was constant across the year.

A note on the early history of electrical stimulation of the human brain

We address inconsistencies in two areas concerning who was first to electrically stimulate a human's brain. First, Boring (1950) and others attributed priority to Eduard Hitzig based on information mentioned somewhat incidentally in Fritsch and Hitzig's (1870) classic work using dogs. Others cited Fritsch and Hitzig but attributed priority to Roberts Bartholow (1874). Second, our examination of translations of Fritsch and Hitzig, especially of footnote 16 in Hitzig's report (1870) of a human case, revealed errors, omissions, and inconsistencies. To aid our inquiry, we requested and received new translations of footnote 16 and of Hitzig's report.

Vibrio vulnificus infection

We report 3 cases of Vibrio vulnificus infections from Taiwan. Patient 1, who manifested symptoms of primary septicemia, died after 2 days. Patient 2, who had a wound infection and signs and symptoms of sepsis but negative blood cultures, responded to tobramycin and chloramphenicol plus surgical debridement, and recovered after 26 days of hospitalization. Patient 3 had secondary septicemia originating from a wound inflicted by a shrimp. Originally, the patient seemed to respond to ceftazidime and amikacin treatment along with surgical debridement, but subsequently died from adult respiratory distress syndrome (ARDS) induced by several episodes of aspiration which occurred after initial clinical improvements. We conclude that, for patients with severe wounds and evidence of V. vulnificus infection, an appropriate, powerful antibiotic, such as one of the third generation cephalosporins should be used as initial therapy unless the nature of the infection indicates other treatment.

Multiple endobronchial granular cell myoblastomas discovered at bronchoscopy

Granular cell myoblastoma is an uncommon benign tumor. Most cases of endobronchial involvement are detected as they become symptomatic. Multiple tumors of the bronchial tree are quite rare, having been reported infrequently in the English literature. The authors report a case with two-year follow-up, which is unique in that the tumors were asymptomatic and were discovered incidentally at bronchoscopy.

Esophageal perforation associated with combined use of the Thumper Resuscitator and esophageal airway

Esophageal perforation is an uncommon but catastrophic complication of resuscitation with the esophageal obturator airway. Three cases of esophageal perforation are reported associated with combined use of an obturator airway and Thumper mechanical resuscitator. The possibility of increased risk when these devices are used together has not been previously discussed in the literature. This risk may be reduced by using lower balloon volumes, less aggressive compressor settings, and obturator airways modified for nasogastric drainage.

Connective tissue arrangement in respiratory airways

Connective tissue provides dynamic stability to the architecture and mechanical function of the lungs. This study examines the parenchymal connective tissue components of the alveolar ducts, their associated respiratory bronchioles and respective alveoli. Thick sections 100 mu and 200 mu, and serial sections at 8 mu of lungs of different ages were examined histologically after fixation in distention. The varying proportions and spatial architecture of the collagen and elastic fibers and the packing and spatial interrelationships of alveoli were studied using graphic serial reconstruction. Alveolar mouth typically have a polygonal configuration as they arise from the airways. Denser connective tissue passes through the polygonal array and forms a helix encircling the airway. Polygonal packing of alveolar mouths provides a mechanically stable ductular structure with conservation of materials. A helical modification of the polygonal arrangement permits reversible changes in linear and circumferential airway dimensions.

Atypical B cell dyscrasia with Bence-Jones proteinuria and intracellular retention of gamma-chains

A case of atypical B cell dyscrasia is described. The patient presented with a history of weakness, bone pain, and bleeding. A K-type paraprotein was found in serum and urine. The histology of bone marrow was that of a malignant lymphoma, but no enlargement of peripheral lymphoid organs was detectable. Peripheral blood lymphocytes were increased in number and included two populations of immature cells, one lymphoid and the other lymphoplasmocytoid. Immunofluorescent staining showed both populations to contain K and gamma chains in their cytoplasm. The clinicopathological heterogeneity suggests a malignant clone of B cells undergoing incomplete maturation, with arrest at different stages of the cell cycle.

Isolation and characterization of tissue-specific isozymes of glucosephosphate isomerase from catfish and conger

In teleosts glucosephosphate isomerase exists as two tissue-specific isozymes. Most tissues contain the more acidic liver-type isozyme, while white muscle contains the more basic isozyme; and a few tissues contain both the liver- and muscle-type isozymes as well as a hybird. The isozymes were isolated from catfish liver and muscle and from conger muscle and shown to be homogeneous by polyacrylamide gel electrophoresis, isoelectric focusing, analytical ultracentrifugation, and rechromatography. Both isozymes are of molecular weight 132,000 (S020,w = 7.0 S) and composed of two subunits of Mr approximately 65,000. The muscle and liver isozymes were shown to have distinct isoelectric points (catfish liver = 6.2; muscle = 7.0) and amino acid compositions. Tryptic peptide maps, after S-carboxymethylation and carbamylation, revealed several distinct differences in the primary structures of the isozymes. Although the isozymes could also be distinguished on the basis of their stabilities, most of their basic catalytic properties were found to be similar. A conger was obtained which was heterozygous for the variant allele at the muscle-glucosephosphate isomerase locus. A comparison of the variant conger muscle isozyme with the wild type revealed a single altered peptide, suggesting a point mutation. The structure-function studies, as well as the genetic studies, clearly establish that the two types of isozymes are of independent genetic origin.