Immunosuppressive CD29+ Treg accumulation in the liver in mice on checkpoint inhibitor therapy

OBJECTIVE

Liver metastases are often resistant to immune checkpoint inhibitor therapy (ICI) and portend a worse prognosis compared with metastases to other locations. Regulatory T cells (Tregs) are one of several immunosuppressive cells implicated in ICI resistance of liver tumours, but the role played by Tregs residing within the liver surrounding a tumour is unknown.

DESIGN

Flow cytometry and single-cell RNA sequencing were used to characterise hepatic Tregs before and after ICI therapy.

RESULTS

We found that the murine liver houses a Treg population that, unlike those found in other organs, is both highly proliferative and apoptotic at baseline. On administration of αPD-1, αPD-L1 or αCTLA4, the liver Treg population doubled regardless of the presence of an intrahepatic tumour. Remarkably, this change was not due to the preferential expansion of the subpopulation of Tregs that express PD-1. Instead, a subpopulation of CD29+ (Itgb1, integrin β1) Tregs, that were highly proliferative at baseline, doubled its size in response to αPD-1. Partial and full depletion of Tregs identified CD29+ Tregs as the prominent niche-filling subpopulation in the liver, and CD29+ Tregs demonstrated enhanced suppression in vitro when derived from the liver but not the spleen. We identified IL2 as a critical modulator of both CD29+ and CD29- hepatic Tregs, but expansion of the liver Treg population with αPD-1 driven by CD29+ Tregs was in part IL2-independent.

CONCLUSION

We propose that CD29+ Tregs constitute a unique subpopulation of hepatic Tregs that are primed to respond to ICI agents and mediate resistance.

The Gut Microbiome Controls Liver Tumors via the Vagus Nerve

Liver cancer ranks amongst the deadliest cancers. Nerves have emerged as an understudied regulator of tumor progression. The parasympathetic vagus nerve influences systemic immunity via acetylcholine (ACh). Whether cholinergic neuroimmune interactions influence hepatocellular carcinoma (HCC) remains uncertain. Liver denervation via hepatic vagotomy (HV) significantly reduced liver tumor burden, while pharmacological enhancement of parasympathetic tone promoted tumor growth. Cholinergic disruption in Rag1KO mice revealed that cholinergic regulation requires adaptive immunity. Further scRNA-seq and in vitro studies indicated that vagal ACh dampens CD8+ T cell activity via muscarinic ACh receptor (AChR) CHRM3. Depletion of CD8+ T cells abrogated HV outcomes and selective deletion of Chrm3 on CD8 + T cells inhibited liver tumor growth. Beyond tumor-specific outcomes, vagotomy improved cancer-associated fatigue and anxiety-like behavior. As microbiota transplantation from HCC donors was sufficient to impair behavior, we investigated putative microbiota-neuroimmune crosstalk. Tumor, rather than vagotomy, robustly altered fecal bacterial composition, increasing Desulfovibrionales and Clostridial taxa. Strikingly, in tumor-free mice, vagotomy permitted HCC-associated microbiota to activate hepatic CD8+ T cells. These findings reveal that gut bacteria influence behavior and liver anti-tumor immunity via a dynamic and pharmaceutically targetable, vagus-liver axis.

Adenosine A2a receptor inhibition increases the anti-tumor efficacy of anti-PD1 treatment in murine hepatobiliary cancers

Backgrounds & Aims

The efficacy of immune checkpoint inhibitor (ICI) therapy for liver cancer remains limited. As the hypoxic liver environment regulates adenosine signaling, we tested the efficacy of adenosine A2a receptor (A2aR) inhibition in combination with ICI treatment in murine models of liver cancer.

Methods

RNA expression related to the adenosine pathway was analyzed from public databases. Peripheral blood mononuclear cells of 13 patients with hepatocellular carcinoma (HCC) were examined by flow cytometry. The following murine cell lines were used: SB-1, RIL175, and Hep55.1c (liver cancer), CT26 (colon cancer), and B16-F10 (melanoma). C57BL/6 and BALB/c mice were used for orthotopic tumor models and were treated with SCH58261, an A2aR inhibitor, in combination with anti-PD1 therapy.

Results

RNA expression of ADORA2A in tumor tissues derived from patients with HCC was higher than in tissues from other cancer types. A2aR+ T cells in peripheral blood from patients with HCC were highly proliferative after immunotherapy. Likewise, in an orthotopic murine model, A2aR expression on T cells increased following anti-PD1 treatment, and the expression of A2aR on T cells increased more in tumor-bearing mice compared with tumor-free mice. The combination of SCH58261 and anti-PD1 led to activation of T cells and reductions in tumor size in orthotopic liver cancer models. In contrast, SCH58261 monotherapy was ineffective in orthotopic liver cancer models and the combination was ineffective in the subcutaneous tumor models tested. CD4+ T-cell depletion attenuated the efficacy of the combination therapy.

Conclusion

A2aR inhibition and anti-PD1 therapy had a synergistic anti-tumor effect in murine liver cancer models.

Impact and implications

Adenosine A2a receptor (A2aR)-expressing T cells in the liver increased in tumor-bearing mice and after anti-PD1 treatment. The combination of an A2aR inhibitor and anti-PD1 treatment had potent anti-tumor effects in two murine models of orthotopic liver cancer. Adenosine A2a receptor blockade promotes immunotherapy efficacy in murine models, highlighting putative clinical benefits for advanced stage liver cancer patients.

Protocol for isolation of signet ring cells from human gastric mucosa

More than 90% of individuals with germline pathogenic CDH1 variants will harbor occult, microscopic foci of signet ring cell carcinomas capable of progressing to advanced diffuse-type gastric cancer. Here, we present a protocol for high viability suspension of signet ring cells from human gastric tissue. We describe the steps for gastric mucosa isolation and tissue dissociation. We then detail procedures for embedding cells into HistoGel for immunohistochemistry staining and additional applications such as flow cytometry and single-cell sequencing.

Early Immune Changes Support Signet Ring Cell Dormancy in CDH1-Driven Hereditary Diffuse Gastric Carcinogenesis

Stage IA gastric adenocarcinoma, characterized by foci of intramucosal signet ring cells (SRC), is found in nearly all asymptomatic patients with germline pathogenic CDH1 variants and hereditary diffuse gastric cancer syndrome (HDGC). The molecular steps involved in initiating malignant transformation and promoting SRC dormancy in HDGC are unknown. Here, whole-exome bulk RNA sequencing (RNA-seq) of SRCs and adjacent non-SRC epithelium (NEP) was performed on laser-capture microdissected (LCM) regions of interest found in risk-reducing total gastrectomy specimens from patients with HDGC (Clinicaltrials.gov ID: NCT03030404). In total, 20 patients (6 male, 14 female) with confirmed HDGC were identified. Analysis of differentially expressed genes (DEG) demonstrated upregulation of certain individual EMT and proliferation genes. However, no oncogenic pathways were found to be upregulated in SRCs. Rather, SRC regions had significant enrichment in pathways involved in T-cell signaling. CIBERSORTx predicted significant increases in the presence of regulatory T cells (Treg) specific to SRC regions. IHC confirmed an increase in FOXP3+ cells in SRC foci, as well as elevations in CD4+ T cells and HLA-DR staining. In summary, the tumor immune microenvironment is microscopically inseparable from stage IA gastric SRCs using a granular isolation technique. An elevation in CD4+ T cells within SRC regions correlates with clinically observed SRC dormancy, while Treg upregulation represents a potential immune escape mechanism.

IMPLICATIONS

Characterization of the tumor-immune microenvironment in HDGC underscores the potential for the immune system to shape the transcriptional profile of the earliest tumors, which suggests immune-directed therapy as a potential cancer interception strategy in diffuse-type gastric cancer.

Tumor-associated macrophages trigger MAIT cell dysfunction at the HCC invasive margin

Mucosal-associated invariant T (MAIT) cells represent an abundant innate-like T cell subtype in the human liver. MAIT cells are assigned crucial roles in regulating immunity and inflammation, yet their role in liver cancer remains elusive. Here, we present a MAIT cell-centered profiling of hepatocellular carcinoma (HCC) using scRNA-seq, flow cytometry, and co-detection by indexing (CODEX) imaging of paired patient samples. These analyses highlight the heterogeneity and dysfunctionality of MAIT cells in HCC and their defective capacity to infiltrate liver tumors. Machine-learning tools were used to dissect the spatial cellular interaction network within the MAIT cell neighborhood. Co-localization in the adjacent liver and interaction between niche-occupying CSF1R+PD-L1+ tumor-associated macrophages (TAMs) and MAIT cells was identified as a key regulatory element of MAIT cell dysfunction. Perturbation of this cell-cell interaction in ex vivo co-culture studies using patient samples and murine models reinvigorated MAIT cell cytotoxicity. These studies suggest that aPD-1/aPD-L1 therapies target MAIT cells in HCC patients.

Preclinical and clinical studies of immunotherapy for the treatment of cholangiocarcinoma

Cholangiocarcinoma (CCA) is a rare primary liver cancer associated with high mortality and few systemic treatment options. The behaviour of the immune system has come into focus as a potential treatment modality for many cancer types, but immunotherapy has yet to dramatically alter the treatment paradigm for CCA as it has for other diseases. Herein, we review recent studies describing the relevance of the tumour immune microenvironment (TIME) in CCA. Various non-parenchymal cell types are critically important in controlling CCA progression, prognosis, and response to systemic therapy. Knowledge of the behaviour of these leukocytes could help generate hypotheses to guide the development of potential immune-directed therapies. Recently, an immunotherapy-containing combination was approved for the treatment of advanced-stage CCA. However, despite level 1 evidence demonstrating the improved efficacy of this therapy, survival remained suboptimal. In the current manuscript, we provide a comprehensive review of the TIME in CCA, preclinical studies of immunotherapies against CCA, as well as ongoing clinical trials applying immunotherapies for the treatment of CCA. Particular emphasis is placed on microsatellite unstable tumours, a rare CCA subtype that demonstrates heightened sensitivity to approved immune checkpoint inhibitors. We also discuss the challenges involved in applying immunotherapies to the treatment of CCA and the importance of understanding the TIME.

Combination of AFP vaccine and immune checkpoint inhibitors slows hepatocellular carcinoma progression in preclinical models

Many patients with hepatocellular carcinoma (HCC) do not respond to the first-line immune checkpoint inhibitor treatment. Immunization with effective cancer vaccines is an attractive alternative approach to immunotherapy. However, its efficacy remains insufficiently evaluated in preclinical studies. Here, we investigated HCC-associated self/tumor antigen, α-fetoprotein-based (AFP-based) vaccine immunization for treating AFP (+) HCC mouse models. We found that AFP immunization effectively induced AFP-specific CD8+ T cells in vivo. However, these CD8+ T cells expressed exhaustion markers, including PD1, LAG3, and Tim3. Furthermore, the AFP vaccine effectively prevented c-MYC/Mcl1 HCC initiation when administered before tumor formation, while it was ineffective against full-blown c-MYC/Mcl1 tumors. Similarly, anti-PD1 and anti-PD-L1 monotherapy showed no efficacy in this murine HCC model. In striking contrast, AFP immunization combined with anti-PD-L1 treatment triggered significant inhibition of HCC progression in most liver tumor nodules, while in combination with anti-PD1, it induced slower tumor progression. Mechanistically, we demonstrated that HCC-intrinsic PD-L1 expression was the primary target of anti-PD-L1 in this combination therapy. Notably, the combination therapy had a similar therapeutic effect in the cMet/β-catenin mouse HCC model. These findings suggest that combining the AFP vaccine and immune checkpoint inhibitors may be effective for AFP (+) HCC treatment.

Cytoreduction and HIPEC for Gastric Carcinomatosis: Multi-institutional Analysis of Two Phase II Clinical Trials

INTRODUCTION

There are no approved locoregional therapies for peritoneal carcinomatosis from gastric adenocarcinoma (GA). Cytoreductive surgery with hyperthermic intraperitoneal chemotherapy (CRS-HIPEC) represents a potential treatment for advanced GA with isolated peritoneal metastasis.

PATIENTS AND METHODS

Two separate single-institution phase II, single-arm studies evaluating CRS-HIPEC using cisplatin with mitomycin C (NIH: NCT03092518, MDACC: NCT02891447) in patients with GA and confirmed peritoneal metastasis were analyzed. The primary endpoint of each trial was overall survival (OS). Clinical, pathologic, and treatment variables were analyzed for association with outcomes.

RESULTS

Over 4 years, 41 patients with peritoneal carcinomatosis from GA underwent CRS-HIPEC. All patients had synchronous peritoneal metastasis and received systemic chemotherapy as front-line therapy. A total of 23 patients also received laparoscopic HIPEC prior to open CRS-HIPEC. The majority (63%, n = 26) were male, and median PCI score at CRS-HIPEC was 2. Median OS was 24.9 months from diagnosis and 14.4 months from CRS-HIPEC. Three-year OS was 25% from diagnosis and 22% from CRS-HIPEC. Median RFS was 7.4 months. The rate of 30-day Clavien-Dindo grade ≥ 3 complications was 32%; specifically, the rate of anastomotic leak was 22%. Multivariable analysis identified the number of pathologically positive lymph nodes as an independent predictor of postoperative OS.

CONCLUSIONS

In patients with gastric adenocarcinoma and isolated peritoneal metastasis treated with CRS-HIPEC, 3-year OS was 22% from CRS-HIPEC, and complications were common. The number of pathologic lymph node metastases was inversely correlated with overall survival. Further investigation of CRS-HIPEC for GA should include patient selection based on response to systemic chemotherapy or incorporate novel intraperitoneal treatment strategies.

Frequent cleft lip and palate in families with pathogenic germline CDH1 variants

Pathogenic and likely pathogenic (P/LP) germline variants in the tumor suppressor gene CDH1 (E-cadherin) result in increased lifetime risk of diffuse-type gastric cancer and lobular breast cancer. CDH1 variants are also associated with hereditary cleft lip and palate (CLP), the mechanism of which is not well understood. We sought to determine the prevalence of CLP in families who carry P/LP CDH1 variants. Patients with P/LP CDH1 variants who were enrolled in a prospective clinical trial were reviewed (NCT03030404). The cohort included 299 individuals from 153 families that had 80 unique P/LP variants in CDH1. The rate of CLP was 19% (29/153) in families reporting CLP in at least one family member, and 2.7% (8/299) among individuals with confirmed germline CDH1 P/LP variants. There were 22 unique variants in CDH1 among the 29 families that reported CLP, or a CLP rate of 27.5% per variant (22/80). 10 of the variants were not previously reported to be associated with CLP. We observed that 24% (7/29) of CLP-associated gene variants involved large-scale (≥1 exon) deletions. Among families with CLP, 69% (20/29) had a member diagnosed with gastric cancer, and 79% (23/29) had a member with breast cancer, which were similar to rates observed in non-CLP families (p >0.3 for both). Our analysis suggests that the prevalence of CLP in families with germline CDH1 P/LP variants was high in this large cohort, and there was no genotype-phenotype pattern. Genetic testing for CDH1 variants should be considered in families with CLP and history of either diffuse-type gastric or lobular breast cancer.

Metformin treatment rescues CD8+ T-cell response to immune checkpoint inhibitor therapy in mice with NAFLD

BACKGROUND & AIMS

Non-alcoholic steatohepatitis (NASH) represents the fastest growing underlying cause of hepatocellular carcinoma (HCC) and has been shown to impact immune effector cell function. The standard of care for the treatment of advanced HCC is immune checkpoint inhibitor (ICI) therapy, yet NASH may negatively affect the efficacy of ICI therapy in HCC. The immunologic mechanisms underlying the impact of NASH on ICI therapy remain unclear.

METHODS

Herein, using multiple murine NASH models, we analysed the influence of NASH on the CD8+ T-cell-dependent anti-PD-1 responses against liver cancer. We characterised CD8+ T cells' transcriptomic, functional, and motility changes in mice receiving a normal diet (ND) or a NASH diet.

RESULTS

NASH blunted the effect of anti-PD-1 therapy against liver cancers in multiple murine models. NASH caused a proinflammatory phenotypic change of hepatic CD8+ T cells. Transcriptomic analysis revealed changes related to NASH-dependent impairment of hepatic CD8+ T-cell metabolism. In vivo imaging analysis showed reduced motility of intratumoural CD8+ T cells. Metformin treatment rescued the efficacy of anti-PD-1 therapy against liver tumours in NASH.

CONCLUSIONS

We discovered that CD8+ T-cell metabolism is critically altered in the context of NASH-related liver cancer, impacting the effectiveness of ICI therapy - a finding which has therapeutic implications in patients with NASH-related liver cancer.

LAY SUMMARY

Non-alcoholic steatohepatitis represents the fastest growing cause of hepatocellular carcinoma. It is also associated with reduced efficacy of immunotherapy, which is the standard of care for advanced hepatocellular carcinoma. Herein, we show that non-alcoholic steatohepatitis is associated with impaired motility, metabolic function, and response to anti-PD-1 treatment in hepatic CD8+ T cells, which can be rescued by metformin treatment.

Novel GLCCI1-BRAF fusion drives kinase signaling in a case of pheochromocytomatosis

INTRODUCTION

Recurrent and metastatic pheochromocytoma (PCC) are rare advanced endocrine neoplasms with limited treatment options. Insight into the pathogenic molecular alterations in patients with advanced PCC can provide therapeutic options for precisely targeting dysregulated pathways.

OBJECTIVE

We report the discovery and characterization of a novel BRAF-containing fusion transcript and its downstream molecular alterations in a patient with recurrent PCC with peritoneal seeding (pheochromocytomatosis).

METHODS

We reviewed the medical record of a patient with pheochromocytomatosis. A comprehensive pan-cancer molecular profiling using next-generation sequencing (NGS) as well as confirmatory real-time-quantitative PCR were performed on surgical specimens. BRAF rearrangement and downstream molecular changes were assayed using fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC), respectively. Western blot was used to assess the in vitro activation of the mitogen-activated protein kinase (MAPK) signaling pathway and the EMT markers in transfected HEK-293 cells.

RESULTS

The NGS analysis of a specimen from a 72-year-old female patient with pheochromocytomatosis showed an in-frame fusion of exon 3 of Glucocorticoid Induced 1 (GLCCI1) to exon 9 of BRAF. The upstream auto-inhibitory domain of BRAF was excluded from the GLCCI1-BRAF fusion; however, the downstream BRAF kinase domain was intact. A BRAF rearrangement was confirmed via a BRAF-specific break-apart FISH assay. Four separate tumor foci harbored GLCCI1-BRAF fusion. IHC demonstrated increased phosphorylated MEK. HEK-293 cells transfected with the GLCCI1-BRAF fusion demonstrated increased phosphorylated MEK as well as higher expression of EMT markers SNAI1 and ZEB1 in vitro.

CONCLUSION

We demonstrate a novel pathogenic gene fusion of GLCCI1 with the oncogenic kinase domain of BRAF, resulting in an activation of the MAPK signaling pathway and EMT markers. Thus, this patient may benefit from clinically available MEK and/or BRAF inhibitors when systemic therapy is indicated.

SUMMARY STATEMENT

This report is the first of GLCCI1 fused to BRAF in a human neoplasm and only the second BRAF-containing fusion transcript in PCC. Detailed molecular characterization of PCC can be a valuable tool in managing patients with recurrent PCC and pheochromocytomatosis that represents a significant clinical challenge.

Abstract 2582: Regulatory T cells restrain efficacy of immunotherapy in murine liver tumors

Background: Checkpoint blockade immunotherapy (CBI) can induce a durable response for some patients with hepatic tumors, but many derive no or incomplete oncologic benefit for unclear reasons. Regulatory T cells (Tregs) in the liver play a central role in maintaining the tolerogenic local immune environment, both in homeostasis and disease. Here we sought to explore the impact of CBI on hepatic Tregs to determine if they play a role in CBI resistance of liver tumors in mice.

Methods: High-dimensional flow cytometry was used to examine the ex vivo characteristics of lymphocytes from both tumor-free and orthotopic tumor-bearing livers of mice treated with CBI or other immunomodulatory agents.

Results: All hepatic T cell subsets examined displayed higher proliferative and apoptotic indices compared with those of splenic T lymphocytes. We found that hepatic Tregs intensely proliferate and undergo apoptosis compared with splenic Tregs under homeostatic conditions. Hepatic Treg proliferation was enhanced after administration of CBI treatment. This effect was abrogated by co-treatment with sirolimus. CD8, macrophages, and the gut microbiome were found to be dispensable for the in vivo in response to αPD1. Co-treatment of mice with αPD1 and αCD25 sensitized MC38-bearing liver tumors.

Conclusion: Murine liver Tregs naturally proliferate and undergo apoptosis due to the mTOR rheostat at homeostasis making them highly responsive to CBI. This behavior potentially explains liver-specific CBI-resistance in tumors.

Citation Format: Benjamin L. Green, Chi Ma, Qianfei Zhang, Benjamin Ruf, Umberto Rosato, Jonathan Qi, Simon Wabitsch, Kylynda Bauer, Yuta Myojin, Justin McCallen, John C. McVey, Varun Subramanyam, Vanessa Catania, Amran Nur, Firouzeh Korangy, Changqing Xie, Tim F. Greten. Regulatory T cells restrain efficacy of immunotherapy in murine liver tumors [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 2582.

Gastric adenocarcinoma peritoneal carcinomatosis: a narrative review

Background and Objective:

Methods:

Key Content and Findings:

Conclusions:

NAFLD indirectly impairs antigen-specific CD8+ T cell immunity against liver cancer in mice

Non-alcoholic fatty liver disease (NAFLD) has become an important etiology leading to liver cancer. NAFLD alters adaptive T cell immunity and has a profound influence on liver cancer development. However, it is unclear how NAFLD affects tumor antigen-specific T cell response. In this study, we generated a doxycycline-inducible MHC-I and -II antigen-expressing HCC cell line which allowed us to investigate tumor antigen-specific T cell response in two NAFLD mouse models. The system proved to be an effective and efficient way to study tumor antigen-specific T cells. Using this model, it was found that NAFLD impairs antigen-specific CD8⁺ T cell immunity against HCC. The effect was not due to reduced generation or intrinsic functional changes of tumor antigen-specific CD8⁺ T cells but caused by accumulated macrophages in the liver environment. The findings suggest that targeting macrophages in NAFLD-driven HCC may improve therapeutic outcomes.

•

The creation of a novel doxycycline-inducible antigen presenting HCC mouse model

•

Diet and genetic NAFLD mice have impaired TAS CD8 T cell response to HCC

•

NAFLD does not change the intrinsic function of TAS CD8 T cells

•

Depletion of macrophages reverses the immunosuppressive environment in NAFLD mice

Anti-PD-1 in Combination With Trametinib Suppresses Tumor Growth and Improves Survival of Intrahepatic Cholangiocarcinoma in Mice

BACKGROUND & AIMS

Intrahepatic cholangiocarcinoma (iCCA) accounts for a fraction of primary liver cancers but has a 5-year survival rate of only 10%. Immune checkpoint inhibitors are effective in treating many solid cancers, but immune checkpoint inhibitor monotherapy has no clear benefit in iCCA. Mitogen-activated kinase (MEK) inhibitors, such as trametinib, have shown promising results in preclinical studies for iCCA by inhibiting cell proliferation and modifying the tumor microenvironment. This study aimed to show the potential benefit of combining trametinib with anti-programmed cell death protein 1 (PD-1) therapy in different iCCA mouse models.

METHODS

Here, we assessed the in vitro cytotoxicity of trametinib in mouse (SB1 and LD-1) and human (EGI-1) cholangiocarcinoma cell lines. We examined the efficacy of single-agent trametinib, anti-PD-1, and a combination of both in subcutaneous, orthotopic, and plasmid-induced iCCA mouse models. Flow cytometry analysis was used to elucidate changes in the tumor immune microenvironment upon treatment. Whole-exome sequencing (WES) was performed on the SB1 tumor cell line to correlate this preclinical model with iCCAs in patients.

RESULTS

Trametinib reduced tumor cell growth of SB1, LD-1, and EGI-1 tumor cells in vitro. Trametinib treatment led to up-regulation of major histocompatibility complex (MHC-I) and programmed cell death ligand 1 (PD-L-1) (programmed cell death ligand 1) on tumor cells in vitro. The combination of trametinib and anti-PD-1 reduced tumor burden in several iCCA tumor models and improved survival in SB1 tumor-bearing mice compared with either agent alone. Immunoprofiling of tumor-bearing mice showed an increase of hepatic effector memory CD8⁺ and CD4⁺ T cells, as well as an increased degranulation of CD8⁺ T cells, indicating enhanced cytotoxicity. WES and somatic mutational analysis showed no mutations of KRAS, BRAF, and ERK in SB1 tumor cells, and showed a similar genetic signature of SB1 found in a cohort of patients with iCCA.

CONCLUSIONS

Altogether, our study shows that trametinib improves the immunogenicity of tumor cells by up-regulating MHC-I surface expression. The combination with anti-PD-1 results in optimal treatment efficacy for iCCA. WES of SB1 cells suggests that KRAS wild-type iCCAs also respond to this combination therapy.

An open-source high-frequency lock-in amplifier

We present characterization of a lock-in amplifier based on a field programmable gate array capable of demodulation at up to 50 MHz. The system exhibits 90 nV/√Hz of input noise at an optimum demodulation frequency of 500 kHz. The passband has a full-width half-maximum of 2.6 kHz for modulation frequencies above 100 kHz. Our code is open source and operates on a commercially available platform.

Csf1r or Mer inhibition delays liver regeneration via suppression of Kupffer cells

INTRODUCTION

Murine Kupffer cells (KCs) comprise CD11bhi and F4/80hi subsets. Tissue-resident macrophages are known to express the tyrosine kinase receptors colony-stimulating factor 1 receptor (Csf1r) and Mer. However, the expression of Csf1r and Mer on KC subsets and the importance of these tyrosine kinases during liver regeneration (LR) are unknown.

METHODS

KCs from wild-type and Csf1r-GFP mice were characterized by flow cytometry. Partial hepatectomy (PH) was performed in mice treated with clodronate liposomes, a Csf1r small molecule inhibitor or depleting antibody, or a small molecule Mer inhibitor. Sera and livers were analyzed. The function of sorted KC subsets was tested in vitro.

RESULTS

Mer was specifically expressed on tissue-resident F4/80hi KCs, 55% of which also expressed Csf1r. Mer+Csf1r+ and Mer+Csf1r- KCs had distinct expression of macrophage markers. Csf1r inhibition in mice reduced F4/80hi KCs by approximately 50%, but did not affect CD11bhi KCs. Clodronate liposomes depleted F4/80hi KCs, but also altered levels of other intrahepatic leukocytes. Csf1r inhibition delayed LR, as demonstrated by a 20% reduction in liver-to-body weight ratios 7 days after PH. At 36h after PH, Csf1r inhibition increased serum ALT and histological liver injury, and decreased liver cell proliferation. A small molecule inhibitor of Mer did not alter the percentage of KCs or their proliferation and just modestly delayed LR. In vitro, Csf1r or Mer inhibition did not decrease KC viability, but did attenuate their cytokine response to stimulation.

CONCLUSIONS

F4/80hi KCs are Mer+ and can be subdivided based on Csf1r expression. Csf1r or Mer inhibition each reduces KC cytokine production and delays LR.

Neutral Silicon-Vacancy Center in Diamond: Spin Polarization and Lifetimes

We demonstrate optical spin polarization of the neutrally charged silicon-vacancy defect in diamond (SiV^{0}), an S=1 defect which emits with a zero-phonon line at 946 nm. The spin polarization is found to be most efficient under resonant excitation, but nonzero at below-resonant energies. We measure an ensemble spin coherence time T_{2}>100  μs at low-temperature, and a spin relaxation limit of T_{1}>25  s. Optical spin-state initialization around 946 nm allows independent initialization of SiV^{0} and NV^{-} within the same optically addressed volume, and SiV^{0} emits within the telecoms down-conversion band to 1550 nm: when combined with its high Debye-Waller factor, our initial results suggest that SiV^{0} is a promising candidate for a long-range quantum communication technology.

Electron paramagnetic resonance and photochromism of N3V0 in diamond

The defect in diamond formed by a vacancy surrounded by three nearest-neighbor nitrogen atoms and one carbon atom, [Formula: see text], is found in the vast majority of natural diamonds. Despite [Formula: see text] being the earliest electron paramagnetic resonance spectrum observed in diamond, to date no satisfactory simulation of the spectrum for an arbitrary magnetic field direction has been produced due to its complexity. In this work, [Formula: see text] is identified in [Formula: see text]-doped synthetic diamond following irradiation and annealing. The [Formula: see text] spin Hamiltonian parameters are directly determined and used to refine the parameters for [Formula: see text], enabling the latter to be accurately simulated and fitted for an arbitrary magnetic field direction. Study of [Formula: see text] under excitation with green light indicates charge transfer between [Formula: see text] and [Formula: see text]. It is argued that this charge transfer is facilitated by direct ionization of [Formula: see text], an as-yet unobserved charge state of [Formula: see text].

Genome and transcriptome profiling of fibrolamellar hepatocellular carcinoma demonstrates p53 and IGF2BP1 dysregulation

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare variant of HCC that most frequently affects young adults. Because of its rarity and an absence of preclinical models, our understanding of FL-HCC is limited. Our objective was to analyze chromosomal alterations and dysregulated gene expression in tumor specimens collected at a single center during two decades of experience with FL-HCC. We analyzed 38 specimens from 26 patients by array comparative genomic hybridiziation (aCGH) and 35 specimens from 15 patients by transcriptome sequencing (RNA-seq). All tumor specimens exhibited genomic instability, with a higher frequency of genomic amplifications or deletions in metastatic tumors. The regions encoding 71 microRNAs (miRs) were deleted in at least 25% of tumor specimens. Five of these recurrently deleted miRs targeted the insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) gene product, and a correlating 100-fold upregulation of IGF2BP1 mRNA was seen in tumor specimens. Transcriptome analysis demonstrated intrapatient tumor similarity, independent of recurrence site or time. The p53 tumor suppressor pathway was downregulated as demonstrated by both aCGH and RNA-seq analysis. Notch, EGFR, NRAS, and RB1 pathways were also significantly dysregulated in tumors compared with normal liver tissue. The findings illuminate the genomic and transcriptomic landscape of this rare disease and provide insight into dysregulated oncogenic pathways and potential therapeutic targets in FL-HCC.

Bacterial amyloids from biofilms break tolerance in lupus

Systemic lupus erythematosus (SLE) is a multifactorial autoimmune disease, in which infections are considered to play a pathogenic role, but the cellular and molecular culprits remain unknown. Bacterial biofilms are multicellular bacterial communities important in the establishment of chronic infection by pathogens. Bacteria produce amyloids, complex proteins with a conserved beta sheet structure that strengthen the extracellular matrix of their biofilms. We have reported that bacterial and eukaryotic DNA is incorporated into curli fibers, functional bacterial amyloids present in Salmonella and E. coli biofilms. I.P. infections with curli-expressing S. Typhimurium or E. coli Nissle, and also systemic administration of curli/DNA complexes purified from Salmonella biofilms accelerated onset in lupus-prone NZBxW/F1 mice and triggered autoantibodies production in non-predisposed mice, suggesting curli/DNA complexes as novel players in SLE pathogenesis. We present here evidence that curli/DNA complexes can activate multiple B cell subsets in vivo. In addition, curli/DNA complexes are capable of directly inducing in vitro polyclonal activation and proliferation of B cells from wildtype mice and from lupus-prone mice and also from 3H9 mice, which are knocked-in for a rearranged anti-DNA Ig heavy chain and whose B cells are normally tolerized for the self-Antigen. Our results suggest that curli/DNA complexes may induce autoantibody production by directly breaking tolerance in autoreactive B cell.

STAT2 Is Required for TLR-Induced Murine Dendritic Cell Activation and Cross-Presentation

TLR-stimulated cross-presentation by conventional dendritic cells (cDCs) is important in host defense and antitumor immunity. We recently reported that cDCs lacking the type I IFN signaling molecule STAT2 are impaired in cross-presenting tumor Ags to CD8(+) T cells. To investigate how STAT2 affects cross-presentation, we determined its requirements for dendritic cell activation. In this study, we report that STAT2 is essential for the activation of murine female cDCs upon TLR3, -4, -7, and -9 stimulation. In response to various TLR ligands, Stat2(-/-) cDCs displayed reduced expression of costimulatory molecules and type I IFN-stimulated genes. The cDC responses to exogenous IFN-α that we evaluated required STAT2 activation, indicating that the canonical STAT1-STAT2 heterodimers are the primary signaling transducers of type I IFNs in cDCs. Interestingly, LPS-induced production of IL-12 was STAT2 and type I IFN receptor (IFNAR) dependent, whereas LPS-induced production of TNF-α and IL-6 was STAT2 and IFNAR independent, suggesting a specific role of the IFNAR-STAT2 axis in the stimulation of proinflammatory cytokines by LPS in cDCs. In contrast, R848- and CpG-induced cytokine production was less influenced by the IFNAR-STAT2 axis. Short kinetics and IFNAR blockade studies showed that STAT2 main function is to transduce signals triggered by autocrine type I IFNs. Importantly, Stat2(-/-) cDCs were deficient in cross-presenting to CD8(+) T cells in vitro upon IFN-α, CpG, and LPS stimulation, and also in cross-priming and licensing cytotoxic T cell killers in vivo. We conclude that STAT2 plays a critical role in TLR-induced dendritic cell activation and cross-presentation, and thus is vital in host defense.

Pharmacological Inhibition of KIT Activates MET Signaling in Gastrointestinal Stromal Tumors

Gastrointestinal stromal tumors (GIST) are the most common adult sarcomas and the oncogenic driver is usually a KIT or PDGFRA mutation. Although GISTs are often initially sensitive to imatinib or other tyrosine kinase inhibitors, resistance generally develops, necessitating backup strategies for therapy. In this study, we determined that a subset of human GIST specimens that acquired imatinib resistance acquired expression of activated forms of the MET oncogene. MET activation also developed after imatinib therapy in a mouse model of GIST (KitV558del/+ mice), where it was associated with increased tumor hypoxia. MET activation also occurred in imatinib-sensitive human GIST cell lines after imatinib treatment in vitro. MET inhibition by crizotinib or RNA interference was cytotoxic to an imatinib-resistant human GIST cell population. Moreover, combining crizotinib and imatinib was more effective than imatinib alone in imatinib-sensitive GIST models. Finally, cabozantinib, a dual MET and KIT small-molecule inhibitor, was markedly more effective than imatinib in multiple preclinical models of imatinib-sensitive and imatinib-resistant GIST. Collectively, our findings showed that activation of compensatory MET signaling by KIT inhibition may contribute to tumor resistance. Furthermore, our work offered a preclinical proof of concept for MET inhibition by cabozantinib as an effective strategy for GIST treatment.

Increased KIT inhibition enhances therapeutic efficacy in gastrointestinal stromal tumor

PURPOSE

Gastrointestinal stromal tumor (GIST) is the most common human sarcoma and a model of targeted molecular therapy. GIST depends on oncogenic KIT signaling and responds to the tyrosine kinase inhibitor imatinib. However, imatinib is rarely curative. We hypothesized that PLX3397, which inhibits KIT and colony-stimulating-factor-1 receptor (CSF1R), would be more efficacious than imatinib in GIST by also depleting tumor-associated macrophages, which are generally thought to support tumor growth.

EXPERIMENTAL DESIGN

We treated Kit(V558del/+) mice that develop GIST or mice with subcutaneous human GIST xenografts with imatinib or PLX3397 and analyzed tumor weight, cellular composition, histology, molecular signaling, and fibrosis. In vitro assays on human GIST cell lines were also performed.

RESULTS

PLX3397 was more effective than imatinib in reducing tumor weight and cellularity in both Kit(V558del)(/+) murine GIST and human GIST xenografts. The superiority of PLX3397 did not depend on depletion of tumor-associated macrophages, because adding CSF1R inhibition did not improve the effects of imatinib. Instead, PLX3397 was a more potent KIT inhibitor than imatinib in vitro. PLX3397 therapy also induced substantial intratumoral fibrosis, which impaired the subsequent delivery of small molecules.

CONCLUSIONS

PLX3397 therapy has greater efficacy than imatinib in preclinical GIST models and warrants study in patients with GIST. The resultant intratumoral fibrosis may represent one of the barriers to achieving complete tumor eradication.

KIT oncogene inhibition drives intratumoral macrophage M2 polarization

Imatinib reduces tumor cell KIT signaling and causes tumor cell apoptosis, which drives TAMs to shift from M1- to M2-like in mouse and human GIST.

Tumor-associated macrophages (TAMs) are a major component of the cancer microenvironment. Modulation of TAMs is under intense investigation because they are thought to be nearly always of the M2 subtype, which supports tumor growth. Gastrointestinal stromal tumor (GIST) is the most common human sarcoma and typically results from an activating mutation in the KIT oncogene. Using a spontaneous mouse model of GIST and 57 freshly procured human GISTs, we discovered that TAMs displayed an M1-like phenotype and function at baseline. In both mice and humans, the KIT oncoprotein inhibitor imatinib polarized TAMs to become M2-like, a process which involved TAM interaction with apoptotic tumor cells leading to the induction of CCAAT/enhancer binding protein (C/EBP) transcription factors. In human GISTs that eventually developed resistance to imatinib, TAMs reverted to an M1-like phenotype and had a similar gene expression profile as TAMs from untreated human GISTs. Therefore, TAM polarization depends on tumor cell oncogene activity and has important implications for immunotherapeutic strategies in human cancers.

Long-term follow-up of the Medical Research Council CLASICC trial of conventional versus laparoscopically assisted resection in colorectal cancer

BACKGROUND

Laparoscopic resection is used widely in the management of colorectal cancer; however, the data on long-term outcomes, particularly those related to rectal cancer, are limited. The results of long-term follow-up of the UK Medical Research Council trial of laparoscopically assisted versus open surgery for colorectal cancer are presented.

METHODS

A total of 794 patients from 27 UK centres were randomized to laparoscopic or open surgery in a 2:1 ratio between 1996 and 2002. Long-term follow-up data were analysed to determine differences in survival outcomes and recurrences for intention-to-treat and actual treatment groups.

RESULTS

Median follow-up of all patients was 62·9 (interquartile range 22·9 - 92·8) months. There were no statistically significant differences between open and laparoscopic groups in overall survival (78·3 (95 per cent confidence interval (c.i.) 65·8 to 106·6) versus 82·7 (69·1 to 94·8) months respectively; P = 0·780) and disease-free survival (DFS) (89·5 (67·1 to 121·7) versus 77·0 (63·3 to 94·0) months; P = 0·589). In colonic cancer intraoperative conversions to open surgery were associated with worse overall survival (hazard ratio (HR) 2·28, 95 per cent c.i. 1·47 to 3·53; P < 0·001) and DFS (HR 2·20, 1·31 to 3·67; P = 0·007). In terms of recurrence, no significant differences were observed by randomized procedure. However, at 10 years, right colonic cancers showed an increased propensity for local recurrence compared with left colonic cancers: 14·7 versus 5·2 per cent (difference 9·5 (95 per cent c.i. 2·3 to 16·6) per cent; P = 0·019).

CONCLUSION

Long-term results continue to support the use of laparoscopic surgery for both colonic and rectal cancer.

Applying interdisciplinary theory in the care of Aboriginal women's mental health

This paper describes theories from various disciplines that are useful in conceptualizing and reflecting on the mental health of Aboriginal women. Critical social theory (sociology), Parse's human becoming theory (nursing) and ecological systems theory (developmental psychology) are considered valuable theories that aid in nursing praxis. These papers discuss how these different theoretical approaches are beneficial for achieving different goals and therefore provide important foundational underpinnings to challenging traditional assumptions that effect human behaviour and practice.

Demographic and geographic variations of oral health among African Americans based on NHANES III

As efforts continue to improve the health of all US citizens, oral health must not be overlooked. Oral health is an integral part of overall health status and oral diseases are among the most prevalent of all health problems.

OBJECTIVES

To describe the oral health status and oral health behaviors of African Americans.

METHODS

The National Health and Nutrition Examination Survey (NHANES III) data set was used to examine a range of oral health indicators of African Americans with specific attention to demographic and geographic factors. The original data set consisted of 20,050 subjects, gathered through the use of complex, multi-stage, stratified and clustered sampling techniques. Only African Americans were included in this study which resulted in a sample of 5,616. Statistical analysis was conducted to allow the proper modeling of the complex, stratified, multistage survey design and sample weights of NHANES III.

RESULTS

Sixty-two percent of respondents indicated that they only visit the dentist when needed and had no regular visitation schedule. Dental health was worse for those individuals who were poor, unemployed, and uninsured. Regional differences in dental care appeared with individuals living in the south reporting poorer dental health.

CONCLUSIONS

The findings from this study are useful for identifying sociodemographic and geographic factors related to oral health status. The insights gained from this study illustrate the need for tailoring oral health promotion programmes and services to specific groups within the African American community because service utilisation and response patterns and perceptions may be different.

Determinants of social support among low-income mothers: a longitudinal analysis

This study examined the reciprocal relationships between perceived mastery, stress, and three functional areas of social support: tangible support, informational support, and belongingness support. Data were collected during two face-to-face interviews with a sample of low-income, primarily African-American mothers, conducted approximately 1 year apart. Consistent with predictions, initial levels of mastery predicted higher subsequent levels of instrumental social supports (tangible and advice support), but were unrelated to belonging support. Conversely, initial levels of tangible support were predictive of later mastery. Perceived stress did not account for any additional variance in subsequent support, although initial levels of belonging support only did predict reduced stress at Time 2. Results suggest that successful attempts to garner instrumental supports is an important contributor to individuals' sense of self-efficacy, at the same time, self-efficacy leads to more successful use of existing social support systems. These findings point to the importance of having both available tangible support networks as well as close emotional supports for low-income parents. The importance of using longitudinal, multidimensional analyses to better understand the social support process is discussed.

Statewide Tuskegee Alliance for clinical trials. A community coalition to enhance minority participation in medical research

BACKGROUND

Cancer mortality rates for all sites are nearly 2.5 times greater for African-Americans compared with whites. In addition, there are data implying that cancer treatment outcomes for minorities are unfavorable compared with whites. Whether this is due to poor access to health care or a biologic property of malignancies occurring in specific populations remains to be determined. Because of these unknown factors, targeting minorities for clinical trials may contribute toward the reduction of the overall morbidity and mortality associated with specific cancers.

METHODS

The current study describes the establishment of a genuine collaborative partnership between the targeted minority community and clinical investigators at the University of Alabama at Birmingham. This partnership was formed for the purpose of identifying strategies that would enhance the accrual and retention of minority participants into current and future cancer prevention and control trials. Focus groups and key informant interviews were conducted to ascertain the community's perception of participating in clinical trials.

RESULTS

The majority of focus group participants were unclear regarding the nature of clinical trials. Participants indicated that they would participate in research studies if they received adequate information regarding the purpose and benefits of the study, and if the charge came from a pastor or physician. Barriers to participation included time commitments, family obligations, whether blood was involved, and past experiences. The majority of the participants indicated that their knowledge of the Tuskegee Syphilis Study did not influence their decision to participate in research. A major outcome of the conference was the formation of the Statewide Tuskegee Alliance Coalition. The planning coalition decided to continue their efforts to work with communities and promote cancer awareness among minorities. After the conference, the coalition conducted several meetings and in July 1998, 1 year after the conference, the coalition selected a chair, co-chair, and a formal name for the organized group.

CONCLUSIONS

The planning, development, and implementation of this conference provided a valuable experience for researchers and community members. It was discovered that community involvement in the early phase of this project contributed to its success. Furthermore, the partnership that developed between researchers (academic institutions) and communities successfully provided an infrastructure that supported the interest of both groups.

Human CYP1B1 Leu432Val gene polymorphism: ethnic distribution in African-Americans, Caucasians and Chinese; oestradiol hydroxylase activity; and distribution in prostate cancer cases and controls

Cytochrome P4501B1 (CYP1B1) is involved in the activation of many carcinogens and in the metabolism of steroid hormones, including 17beta-oestradiol (E2) and testosterone. We report a significant difference in the allele frequencies of two point mutations in the coding region of the CYP1B1 gene among Caucasian (n = 189), African-American (n = 52) and Chinese (Linxian) (n = 109) populations. A (C to G) transversion at position 1666 in exon 3, which results in an amino acid substitution of Leu432 to Val, was present in African-Americans with an allele frequency for Va1432 of 0.75, in Caucasians of 0.43, and in Chinese of 0.17. A (C to T) transition at position 1719 in exon 3, with no amino acid change (Asp449), appeared to be closely linked with the Val432 variant. Results using human lung microsomal preparations from individuals with the CYP1B1Val/Val and CYP1B1Leu/Leu genotypes indicate that Val432 variant may be a high activity allele and thus may contribute to the interindividual differences in CYP1B1 activity. Because CYP1B1 is involved in hormone and carcinogen metabolism, and given the disparate rates of prostate cancer among ethnic groups, we also evaluated the association of the CYP1B1 Leu432Val polymorphism with prostate cancer risk in a pilot case-control study. Among Caucasians, 34% of men with cancer (n = 50) were homozygous for the Val432 polymorphism, while only 12% of matched control subjects (n = 50) had this genotype. These preliminary data indicate that genetic polymorphisms in CYP1B1 might play an important role in human prostate carcinogenesis.

Minority recruitment in clinical trials: a conference at Tuskegee, researchers and the community

PURPOSE

This article describes the planning, implementation, and evaluation of a 2-day conference designed to examine the factors related to the participation of African Americans in cancer clinical trials.

METHODS

Pre-conference formative evaluations (e.g., focus group discussions and key informant interviews with community leaders and health providers) were conducted in several rural and urban counties in the state of Alabama to determine African Americans' perceptions of participation in clinical research. The findings from these evaluations were used to develop a conference format and agenda. The 2-day conference included: (i) a pretest of African Americans' perceptions of cancer research, participation factors, and communication and recruitment issues; (ii) individual presentations high-lighting community leaders, church leaders, and researchers' perspectives regarding minority participation in research; (iii) working group discussions regarding the barriers and solutions to minority participation in research; and (iv) a posttest evaluation to measure changes in African Americans' perceptions of research.

RESULTS

Several recruitment barriers and solutions were identified and reported by the working groups. Comparisons of the pretest and posttest measures showed significant (p > .05) and favorable shifts in the areas of perceptions of cancer research, participation factors, communication issues, and recruitment issues. Participation in the conference reflected a positive change in attitudes on these measures. However, the theme, "barriers that contributed to nonparticipation," did not show any significant changes during the two testing periods. The most critical lesson that resulted from this conference was the need for researchers and community members to have open dialogue about participation in research.

CONCLUSIONS

This conference demonstrated that progress can be made when all parties are at the "table" and can be heard. In this model, community members proved to be valuable resources in providing researchers with information that was vital to the success of recruitment and retention studies and trials.

The Children's PTSD Inventory: development and reliability

Information involving the development of the DSM-IV version of the Children's PTSD Inventory is described. Independent ratings by highly experienced judges denote that the instrument encompassed the universe of definition that it was intended to measure (i.e., the DSM-IV criteria for PTSD). The instrument was administered to 82 traumatized and 22 nontraumatized youths at Bellevue Hospital. Moderate to high Cronbach alphas (.53-.89) were evident at the subtest level. An alpha of .95 was evident at the diagnostic level. In terms of inter-rater reliability, 98.1% agreement was evident at the diagnostic level. Inter-rater intraclass correlation coefficients (ICCs) ranged from .88 to .96 at the subtest level and .98 at the diagnostic level. Good to excellent kappas (.66-1.00) were reported for inter-rater reliability at the subtest level. An inter-rater reliability kappa of .96 was evident at the diagnostic level. In terms of test-retest reliability, 97.6% agreement was evident at the diagnostic level. Good to excellent test-retest kappas (.66-1.00) and ICCs (.66-.94) were observed. A test-retest kappa of .91 and an ICC of .88 was observed at the diagnostic level.

Detection of magnetism in the red imported fire ant (Solenopsis invicta) using magnetic resonance imaging

Red imported fire ant (Solenopsis invicta) workers, queens, and alates were analyzed by magnetic resonance imaging (MRI) for the presence of natural magnetism. Images of ants showed distortion patterns similar to those of honey bees and monarch butterflies, both of which possess ferromagnetic material. The bipolar ring patterns of MRI indicated the presence in fire ants of small amounts of internal magnetic material, which may be used in orientation behaviors, as in the honey bees.

Assessing the health attitudes, beliefs, and behaviors of African Americans attending church: a comparison from two communities

Public health officials and researchers continue to be increasingly concerned about the health of populations of color, especially African Americans. A survey was administered in African American churches in two communities (Wichita, KS and Tuscaloosa, AL) to gather information concerning health behaviors and beliefs and to design interventions that might improve their health status. The study examined the homogeneity of attitudes, beliefs, and behaviors across these samples and to determine the readiness to change using the Transtheoritical Model. Individuals completed a 33-item survey: 6 demographic questions, 12 health behavior questions, 8 health belief questions, 3 church attendance questions, and 4 church-based health promotion program questions. The total sample consisted of 429 respondents. The results showed that 93% of respondents have had their blood pressure checked in the past 2 years. While only 44% indicated eating a high fiber diet during the week. Thirty percent of respondents indicated that their health was dependent on fate or destiny. The findings from this study confirm that among both samples that health attitudes, beliefs, and behaviors need to be changed to lower the risk of certain diseases and disorders. The findings also indicate that both samples have similar beliefs about health that may have important implications for disseminating information to the community. Innovative and culturally sensitive programs are needed in the African American community if disparities in health are to diminish.

African-American attitudes regarding cancer clinical trials and research studies: results from focus group methodology

Despite federal recommendations highlighting the need to include special population groups (mainly minorities and women) in clinical research, recruitment and retention of these groups present a great challenge to researchers. This paper describes a focus group study that was conducted to examine factors related to minority participation and retention in cancer clinical research studies. In 1996, the National Cancer Institute submitted a request for applicants to receive support for regional conferences. The purpose of the proposed conferences was to share current information and strategies to aid cancer clinical investigators in recruiting and retaining minority participants in clinical cancer research and to stimulate local/regional adaptations of these strategies. The University of Alabama at Birmingham (UAB), The University of Alabama, and Tuskegee University collaborated to respond to the request. Funding was granted by NCI for the regional conference in Alabama. The conference was held in Tuskegee, Alabama, the site of the infamous US Public Health Syphilis Study at Tuskegee. In planning for the conference, focus group sessions were conducted with African-American men and women who represented all regions of Alabama. The focus group information was used to identify important issues to be addressed at the conference.

Outcomes of single versus multiple trauma exposure in a screening sample

Most studies ignore prior trauma exposure when evaluating outcomes of target events. This study explored symptom severity associated with different types of traumatic experiences occurring alone and with multiple exposure. The Stressful Life Events Screening Questionnaire categorized 1,909 sophomore women into groups including no trauma exposure, exposure to a serious non-Criterion A event only, exposure to several unique noninterpersonal and interpersonal events, and exposure to multiple interpersonal events. Women with noninterpersonal trauma did not differ from those without trauma on the Trauma Symptom Inventory. Only interpersonal trauma and non-Criterion A events were associated with elevated symptoms; multiple-exposure participants had significantly higher symptoms than all other groups. Complex trauma histories should be accounted for, even in studies of one target event.

Predictors and outcomes of posttraumatic stress disorder in World War II veterans exposed to mustard gas

Current posttraumatic stress disorder (PTSD) associated with participation in secret military tests of mustard gas during World War II was assessed in 363 male military veterans who were randomly sampled from a registry developed by the Department of Veterans Affairs. Current prevalence was 32% for full PTSD and 10% for partial PTSD. Prevalence of PTSD varied as a function of risk and protective factors, including volunteering, physical symptoms during the tests, and prohibited disclosure. Prediction of partial PTSD was weaker than prediction of full PTSD. Veterans with full PTSD reported poorer physical health, a higher likelihood of several chronic illnesses and health-related disability, greater functional impairment, and higher likelihood of health care use than those with no PTSD. Veterans with partial PTSD also had poorer outcomes than did veterans with no PTSD in a subset of these domains. There is discussion of the traumatic elements of experimental mustard gas exposure, vulnerability to PTSD, and the relevance of these findings to understanding the broad range of outcomes associated with PTSD.

Trauma history as a predictor of psychologic symptoms in women with breast cancer

PURPOSE

To identify predictors of psychiatric problems in women with early-stage breast cancer.

PATIENTS AND METHODS

One hundred sixty women with early-stage breast cancer were recruited from three treatment centers. They filled out self-report questionnaires, including a medical history and demographic survey, the Trauma History Questionnaire, Life Event Questionnaire, Brief Symptom Inventory, Beck Depression Inventory, and Duke-UNC Functional Social Support Questionnaire, and were evaluated using the Structured Clinical Interview for DSM-III-R.

RESULTS

Hierarchical regression analyses indicated that four of five variable sets made a significant incremental contribution to outcome prediction, with 35% to 37% of the variance explained. Outcomes were predicted by demographic variables, trauma history variables, precancer psychiatric diagnosis, recent life events, and perceived social support. Cancer treatment variables did not predict outcome.

CONCLUSION

The findings highlight the important roles of trauma history and recent life events in adjustment to cancer and have implications for screening and treatment.

Virus passage through track-etch membranes modified by salinity and a nonionic surfactant

Why do viruses sometimes not pass through larger pores in track-etch filters? Increasing the salinity (0.8 to 160 mM Na+) decreased phiX174 and PRD1 passage through track-etch polycarbonate membranes (sodium dodecyl sulfate coated but not polyvinylpyrrolidone coated) and PRD1 passage through polyester membranes. Undiminished passage when 0.1% Tween 80 was added implied that nonionic virus adsorption occurred and indicated that high levels of salinity decreased virus passage by decreasing electrostatic repulsion that prevented adsorption.

Children's responses to a nuclear waste disaster: PTSD symptoms and outcome prediction

OBJECTIVE

To examine the psychological impact of living near a nuclear waste disaster that involved ongoing threat of radioactive contamination.

METHOD

Participants were an exposed sample (residence within a 5-mile radius of the nuclear plant) of 120 children (7-15 years old) and their parents and a nonexposed comparison sample of 60 children and their parents. Parent and self-ratings of the children's psychological functioning and posttraumatic stress disorder (PTSD) symptoms were obtained, along with cognitive variables.

RESULTS

Minimal differences between the 2 samples were found. In the exposed sample, stress responses for the child self-reports showed several age group by gender interactions. Girls' PTSD symptoms tended to increase with age while boys' symptoms decreased, with intrusion showing the strongest effects. While child and parent PTSD symptom ratings were correlated, children reported approximately twice as many symptoms. Cognitive understanding increased with age and was greater in boys. Exposure and parent functioning significantly predicted outcome.

CONCLUSIONS

Age and gender effects after disaster might best be explored as an interaction. While disaster effects were mild, the psychological health of the parents may be an important determinant of psychological health in children in this type of disaster.

The impact of a monensin controlled-release capsule on subclinical ketosis in the transition dairy cow

An experiment was designed to examine subclinical ketosis in periparturient dairy cows and the antiketogenic effects of monensin. Subclinical ketosis was induced through a 10% feed restriction and was quantitatively determined using a blood beta-hydroxybutyrate (BHBA) threshold of 1200 mumol/L. Monensin decreased the BHBA concentration by 35% and increased the glucose concentration by 15%. No effect of monensin on milk production was detected, but rumen fermentation was altered. Monensin decreased the acetate to propionate ratio, decreased the butyrate concentration, and increased pH. The lower concentration of BHBA in blood and higher concentration of blood glucose in cows treated with a monensin controlled-release capsule decreased subclinical ketosis in early lactation cows.

Prospective social-psychological factors of adolescent smoking progression

PURPOSE

To evaluate the ability of social-psychological risk factors to predict adolescent smoking behavior.

METHODS

Nonsmoking adolescents (n = 4032) who participated in the 1989 and 1993 Teenage Attitudes and Practices Surveys (TAPS I) were selected for analyses. Four multivariate logistic models were used to examine (a) adolescents' smoking initiation, (b) adults' smoking initiation, (c) adolescents' progression to regular smoking, and (d) adults' progression to regular smoking. A series of social-psychological variables were measured.

RESULTS

All four models were significant. However, no social-psychological factors were consistently significant in all four models, except white ethnicity. Data showed that social-psychological factors are less able to predict the transition from nonsmoking to experimental smoking than that from nonsmoking to regular smoking.

CONCLUSIONS

Future prospective studies should measure both social-psychological and smoking acquisition factors at closer intervals to more accurately examine potential relationships.