Phuong L. Nguyen

CD4+ T Cell Depletion during all Stages of HIV Disease Occurs Predominantly in the Gastrointestinal Tract

The mechanisms underlying CD4+ T cell depletion in human immunodeficiency virus (HIV) infection are not well understood. Comparative studies of lymphoid tissues, where the vast majority of T cells reside, and peripheral blood can potentially illuminate the pathogenesis of HIV-associated disease. Here, we studied the effect of HIV infection on the activation and depletion of defined subsets of CD4+ and CD8+ T cells in the blood, gastrointestinal (GI) tract, and lymph node (LN). We also measured HIV-specific T cell frequencies in LNs and blood, and LN collagen deposition to define architectural changes associated with chronic inflammation. The major findings to emerge are the following: the GI tract has the most substantial CD4+ T cell depletion at all stages of HIV disease; this depletion occurs preferentially within CCR5+ CD4+ T cells; HIV-associated immune activation results in abnormal accumulation of effector-type T cells within LNs; HIV-specific T cells in LNs do not account for all effector T cells; and T cell activation in LNs is associated with abnormal collagen deposition. Taken together, these findings define the nature and extent of CD4+ T cell depletion in lymphoid tissue and point to mechanisms of profound depletion of specific T cell subsets related to elimination of CCR5+ CD4+ T cell targets and disruption of T cell homeostasis that accompanies chronic immune activation.

A placebo-controlled, double-blind trial of infliximab for cancer-associated weight loss in elderly and/or poor performance non-small cell lung cancer patients (N01C9)

PURPOSE This study tested whether infliximab, a chimeric IgG1kappa monoclonal antibody that blocks tumor necrosis factor (TNF) alpha, improves/stabilizes weight loss in elderly and/or poor performance status patients with metastatic non-small cell lung cancer (NSCLC). METHODS This double-blind trial randomly assigned patients to infliximab/docetaxel (n=32) versus placebo/docetaxel (n=29). The primary endpoint was > or = 10% weight gain. RESULTS Groups were balanced with respect to age, number of prior chemotherapy regimens, baseline weight loss, and performance status. No patient gained > or = 10% baseline weight, and early evidence of the lack of efficacy prompted early trial closure. Appetite improvement was negligible in both arms. However, infliximab-/docetaxel-treated patients developed greater fatigue and worse global quality of life scores. Other outcomes, such as tumor response rate (<10% in both groups) and overall survival, were not statistically different between groups. There were no statistically significant differences in adverse events, although one death was attributed to infliximab. Genotyping for the TNF alpha -238 and -308 polymorphisms revealed no clinical significance of these genotypes, as relevant to the loss of weight or appetite. CONCLUSIONS This trial closed early because infliximab did not prevent or palliate cancer-associated weight loss. Infliximab was associated with increased fatigue and inferior global quality of life.

A placebo-controlled double blind trial of etanercept for the cancer anorexia/weight loss syndrome : Results from N00C1 from the north central cancer treatment group

Tumor necrosis factor‐α (TNF‐α) is a putative mediator of the cancer anorexia/weight loss syndrome. The current study was designed to determine whether etanercept (a dimeric fusion protein consisting of the extracellular ligand‐binding portion of the human 75‐kilodalton TNF receptor linked to the Fc portion of human immunoglobulin [Ig] G1) could palliate this syndrome.

Risk of adult acute and chronic myeloid leukemia with cigarette smoking and cessation

BACKGROUND Cigarette smoking is an established risk factor for adult myeloid leukemia, particularly acute myeloid leukemia (AML), but less is known about the nature of this association and effects of smoking cessation on risk. METHODS In a large population-based case-control study of myeloid leukemia that included 414 AML and 185 chronic myeloid leukemia (CML) cases and 692 controls ages 20-79 years, we evaluated risk associated with cigarette smoking and smoking cessation using unconditional logistic regression methods and cubic spline modeling. RESULTS AML and CML risk increased with increasing cigarette smoking intensity in men and women. A monotonic decrease in AML risk was observed with increasing time since quitting, whereas for CML, the risk reduction was more gradual. For both AML and CML, among long-term quitters (≥30 years), risk was comparable to non-smokers. CONCLUSIONS Our study confirms the increased risk of myeloid leukemia with cigarette smoking and provides encouraging evidence of risk attenuation following cessation.

The Myelodysplastic Syndromes

Myelodysplastic syndromes (MDS) are a heterogeneous group of bone marrow disorders that affect mostly the elderly and have a variable probability of progression to acute leukemia. The diagnosis of MDS rests largely on a critical morphologic review of blood and bone marrow slides, with careful correlation with other clinical and essential laboratory data, including cytogenetics. This article discusses the epidemiology and clinical and pathologic features of MDS and pertinent diagnostic and prognostic classifications, with a brief overview of treatment options. Other considerations in the differential diagnosis are also briefly outlined.

Nonsteroidal Anti-inflammatory Drug and Acetaminophen Use and Risk of Adult Myeloid Leukemia

Background: Little is known about the causes of adult leukemia. A few small studies have reported a reduced risk associated with regular use of nonsteroidal anti-inflammatory drugs (NSAID). Methods: In a population-based case–control study, we evaluated analgesic use among 670 newly diagnosed myeloid leukemia cases [including 420 acute myeloid leukemias (AML) and 186 chronic myeloid leukemias (CML)] and 701 controls aged 20 to 79 years. Prior use of aspirin, ibuprofen, acetaminophen, other NSAIDs, and COX-2 inhibitors was assessed and included frequency, duration, and quantity. ORs and 95% CIs were calculated using unconditional logistic regression adjusting for potential confounders. Results: Regular/extra strength aspirin use was inversely associated with myeloid leukemia in women (OR = 0.59, 95% CI = 0.37–0.93) but not in men (OR = 0.85, 95% CI = 0.58–1.24). In contrast, acetaminophen use was associated with an increased risk of myeloid leukemia in women only (OR = 1.60, 95% CI = 1.04–2.47). These relationships were stronger with increasing dose and duration. When stratified by leukemia type, aspirin use was inversely associated with AML and CML in women. No significant overall associations were found with ibuprofen or COX-2 inhibitors for either sex; however, a decreased risk was observed with other anti-inflammatory analgesic use for women with AML or CML (OR = 0.47, 95% CI = 0.22–0.99; OR = 0.31, 95% CI = 0.10–0.92, respectively). Conclusions: Our results provide additional support for the chemopreventive benefits of NSAIDs, at least in women. Because leukemia ranks fifth in person-years of life lost due to malignancy, further investigation is warranted. Impact: NSAIDs may reduce, whereas acetaminophen may increase, myeloid leukemia risk in women. Cancer Epidemiol Biomarkers Prev; 20(8); 1741–50. ©2011 AACR.

Obesity over the life course and risk of acute myeloid leukemia and myelodysplastic syndromes

BACKGROUND Overweight and obesity are known risk factors for a number of cancers, with recent evidence suggesting that risk of hematologic cancer is also increased in obese individuals. We evaluated associations between body mass index (BMI) at differing time points during the life course in population-based case control studies of acute myeloid leukemia (AML) and myelodysplatic syndromes (MDS). METHODS Cases were identified by the Minnesota Cancer Surveillance System. Controls were identified through the Minnesota State drivers license/identification card list. BMI was calculated using self-reported height and weight at ages 18, 35, and 50 years and two years prior to interview, and categorized as normal (18.5-25 kg/m(2)), overweight (25-29.9 kg/m(2)), obese class I (30-34.9 kg/m(2)), and obese class II/III (35+ kg/m(2)). All analyses were stratified by sex. Unconditional logistic regression was used to calculate odds ratios and 95% confidence intervals. RESULTS We included 420 AML cases, 265 MDS cases and 1388 controls. Obesity two years prior to diagnosis was associated with AML in both males and females (OR=2.22, 95% CI 1.28, 3.85 and OR=1.85, 95% CI 1.08, 3.15 for BMI≥35 vs. BMI 18.5-24.9, respectively). In contrast, associations between obesity and MDS were observed only in females. Weight change in adulthood was not consistently associated with either outcome. CONCLUSION Our results extend the emerging literature suggesting that obesity is a risk factor for hematologic malignancy and provide evidence that that the association remains regardless of timing of obesity. Obesity in adulthood is a modifiable risk factor for both MDS and AML.

Bone Marrow Morphologic Features in Polycythemia Vera With JAK2 Exon 12 Mutations

The diagnosis of polycythemia vera (PV) requires the integration of clinical and laboratory findings, bone marrow morphologic features, and JAK2 analysis. JAK2(V617F) (exon 14) mutation is found in 95% of PV cases. Functionally similar mutations in JAK2 exon 12 have also been described, but a thorough bone marrow study has not been done. We identified 7 PV cases with exon 12 mutations; all had hypercellular bone marrow with erythroid hyperplasia. Small, atypical megakaryocytes predominated; atypical megakaryocyte lobation and abnormal chromatin distribution was identified in all cases. Rare clusters of megakaryocytes could be found but were typically subtle. Because JAK2 exon 12-positive PV cases lack the classic myeloproliferative morphologic features, bone marrow samples from the patients may be difficult to classify as myeloproliferative neoplasms. Clinically suspected PV with low serum erythropoietin and absent JAK2(V617F), together with the bone marrow findings of erythroid hyperplasia and subtle megakaryocytic atypia, should prompt an evaluation for an exon 12 mutation.

Clinical and laboratory characteristics in congenital ANKRD26 mutation-associated thrombocytopenia: A detailed phenotypic study of a family.

Abstract The clinical and laboratory characteristics of patients with non-syndromic, autosomal dominant thrombocytopenia secondary to germ line ANKRD26 mutations appear to be heterogeneous. Except for a targeted molecular genotyping approach, there is no distinct clinical or laboratory phenotype that has been specifically associated with this particular gene mutation. Such heterogeneity could be due to variations in mutation and genetic background in different families. To understand the phenotypic heterogeneity, we thoroughly studied one affected family using the International Society for Thrombosis and Haemostasis bleeding assessment tool and both clinically validated standard and esoteric platelet testing (electron microscopy (EM) and flow cytometry). We found that decreased platelet aggregation with arachidonic acid and epinephrine agonists was common in affected family members. EM studies demonstrated persistent borderline low mean dense granules per platelet, decreased alpha granules and an increased canalicular network pattern in all affected members. Since these characteristics are subtle or non-pathognomonic, molecular testing for ANKRD26 mutation remains the most reliable test to render a diagnosis and should be considered when evaluating a patient or family with congenital thrombocytopenia, particularly if there is a history of myeloid neoplasms.

Factors Controlling Levels of CD8+ T-Cell Lymphocytosis Associated with Murine γ-Herpesvirus Infection

Intranasal infection of mice with murine gamma-herpesvirus 68 (MHV-68) elicits a striking CD8+ T-cell lymphocytosis following the establishment of latency, which includes a marked increased frequency of Vbeta4+ CD8+ T cells. The Vbeta4+ CD8+ T cells do not recognize a conventional viral peptide, but are stimulated by an uncharacterized ligand expressed on latently infected, activated B cells. The selective expansion of Vbeta4+ CD8+ T cells after MHV-68 infection is observed in all mouse strains examined, although the fold-increase varies widely, ranging from less than twofold to greater than 10-fold. The factors controlling the variation are currently undefined. In the current study, CD8+ T cell activation and Vbeta4+ CD8+ T-cell frequencies were analyzed in 18 inbred strains of mice. The data show that the magnitude of the Vbeta4+ CD8+ T-cell response correlates with the degree of CD8+ T cell-activation, and that both major histocompatibility complex (MHC) and non-MHC genes contribute to the magnitude of the activation. Furthermore, the magnitude of the response does not reflect major differences in susceptibility to viral infection and/or corresponding differences in the acute response. Rather the degree of Vbeta4+ CD8+ T cell activation may be determined by differences in levels of expression of the stimulatory ligand at the peak of latency.