Citations

Abstract Bag3, a nucleotide exchange factor of the heat shock protein Hsp70, has been implicated in cell signaling. Here, we report that Bag3 interacts with the SH3 domain of Src, thereby mediating the effects of Hsp70 on Src signaling. Using several complementary approaches, we established that the Hsp70–Bag3 module is a broad-acting regulator of cancer cell signaling by modulating the activity of the transcription factors NF-κB, FoxM1, Hif1α, the translation regulator HuR, and the cell-cycle regulators p21 and survivin. We also identified a small-molecule inhibitor, YM-1, that disrupts the Hsp70–Bag3 interaction. YM-1 mirrored the effects of Hsp70 depletion on these signaling pathways, and in vivo administration of this drug was sufficient to suppress tumor growth in mice. Overall, our results defined Bag3 as a critical factor in Hsp70-modulated signaling and offered a preclinical proof-of-concept that the Hsp70–Bag3 complex may offer an appealing anticancer target. Cancer Res; 74(17); 4731–40. ©2014 AACR.

ABSTRACT Rothia spp. are Gram-positive cocco-bacilli that cause a wide range of serious infections, especially in immunocompromised hosts. Risk factors for Rothia mucilaginosa (previously known as Stomatococcus mucilaginosus ) bacteremia include prolonged and profound neutropenia, malignancy, and an indwelling vascular foreign body. Here, we describe 67 adults at the Mayo Clinic in Rochester, MN, from 2002 to 2012 with blood cultures positive for Rothia . Twenty-five of these patients had multiple positive blood cultures, indicating true clinical infection. Among these, 88% (22/25) were neutropenic, and 76% (19/25) had leukemia. Common sources of bacteremia were presumed gut translocation, mucositis, and catheter-related infection. One patient died with Rothia infection. Neutropenic patients were less likely to have a single positive blood culture than were nonneutropenic patients. Antimicrobial susceptibility testing was performed on 21% of the isolates. All of the tested isolates were susceptible to vancomycin and most beta-lactams; however, four of six tested isolates were resistant to oxacillin. There was no difference between the neutropenic and nonneutropenic patients in need of intensive care unit care, mortality, or attributable mortality.

AbstractMastocytosis is an emerging differential diagnosis in patients with more or less specific mediator‐related symptoms. In some of these patients, typical skin lesions are found and the diagnosis of mastocytosis can be established. In other cases, however, skin lesions are absent, which represents a diagnostic challenge. In the light of this unmet need, we developed a diagnostic algorithm for patients with suspected mastocytosis. In adult patients with typical lesions of mastocytosis in the skin, a bone marrow (BM) biopsy should be considered, regardless of the basal serum tryptase concentration. In adults without skin lesions who suffer from mediator‐related or other typical symptoms, the basal tryptase level is an important parameter. In those with a slightly increased tryptase level, additional investigations, including a sensitive KIT mutation analysis of blood leucocytes or measurement of urinary histamine metabolites, may be helpful. In adult patients in whom (i) KIT D816V is detected and/or (ii) the basal serum tryptase level is clearly increased (>25–30 ng/ml) and/or (iii) other clinical or laboratory features suggest the presence of ‘occult’ mastocytosis or another haematologic neoplasm, a BM investigation is recommended. In the absence of KIT D816V and other signs or symptoms of mastocytosis or another haematopoietic disease, no BM investigation is required, but the clinical course and tryptase levels are monitored in the follow‐up. In paediatric patients, a BM investigation is usually not required, even if the tryptase level is increased. Although validation is required, it can be expected that the algorithm proposed herein will facilitate the management of patients with suspected mastocytosis and help avoid unnecessary referrals and investigations.

ABSTRACT Travel distance, growing disability, and uneven distribution of doctors limit access to care for most Parkinson's disease (PD) patients worldwide. Telemedicine, the use of telecommunications technology to deliver care at a distance, can help overcome these barriers. In this report, we describe the past, present, and likely future applications of telemedicine to PD. Historically, telemedicine has relied on expensive equipment to connect single patients to a specialist in pilot programs in wealthy nations. As the cost of video conferencing has plummeted, these efforts have expanded in scale and scope, now reaching larger parts of the world and extending the focus from care to training of remote providers. Policy, especially limited reimbursement, currently hinders the growth and adoption of these new care models. As these policies change and technology advances and spreads, the following will likely develop: integrated care networks that connect patients to a wide range of providers; education programs that support patients and health care providers; and new research applications that include remote monitoring and remote visits. Together, these developments will enable more individuals with PD to connect to care, increase access to expertise for patients and providers, and allow more‐extensive, less‐expensive participation in research. © 2014 International Parkinson and Movement Disorder Society

Patients with diffuse large B‐cell lymphoma (DLBCL) and pre‐treatment bone marrow (BM) involvement require a restaging BM biopsy to document complete remission (CR). We investigated whether BM assessment by restaging PET‐CT could obviate the need for a repeat BM biopsy. Patients with DLBCL and a positive BM biopsy at diagnosis were identified from the Mayo Clinic Lymphoma Data Base. The concordance of BM status on restaging histopathology and PET‐CT reports and the positive (PPV) and negative predictive value (NPV) of PET‐CT were determined. One thousand eighty patients with DLBCL were evaluated and 69 patients (6%) had DLBCL involving the BM at diagnosis. Of 46 patients who completed frontline chemoimmunotherapy, 34 had a restaging PET‐CT and BM biopsy and were included in the analysis. Thirty‐three patients had a negative BM by both PET‐CT and BM biopsy; one patient had persistent BM involvement by biopsy and PET‐CT. Thus, restaging PET‐CT had 100% PPV and 100% NPV for assessing residual BM disease. The findings were validated in a prospective cohort of 68 DLBCL patients treated on a phase II clinical trial where four patients (6%) had DLBCL involving the BM at diagnosis. All had a negative BM by both restaging BM biopsy and PET‐CT. Compared with the gold standard of BM biopsy, PET‐CT had a 100% NPV to exclude residual BM disease after frontline therapy. If further validated, DLBCL practice guidelines and response criteria could be modified so that BM biopsy is no longer required to document CR if the restaging PET‐CT is negative. Am. J. Hematol. 89:865–867, 2014. © 2014 Wiley Periodicals, Inc.

This report describes a toddler who presented to the emergency department with reported leg weakness and a petechial rash who ultimately was diagnosed with severe ascorbic acid deficiency (scurvy) due to restricted dietary intake. The diagnosis was delayed, and this report highlights the role of a detailed dietary history as part of the diagnostic process.

Abstract Studies in cancer patients have suggested that breast tumors recruit regulatory T cells (Tregs) into the tumor microenvironment. The extent to which local Tregs suppress antitumor immunity in breast cancer is unknown. We questioned whether inhibiting systemic Tregs with an IL-2 immunotoxin in a model of neu-mediated breast cancer, the neu-transgenic mouse, could impact disease progression and survival. As in human breast cancer, cancers that develop in these mice attract Tregs into the tumor microenvironment to levels of ∼10–25% of the total CD4+ T cells. To examine the role of Tregs in blocking immune-mediated rejection of tumor, we depleted CD4+CD25+ T cells with an IL-2 immunotoxin. The treatment depleted Tregs without concomitant lymphopenia and markedly inhibited tumor growth. Depletion of Tregs resulted in a persistent antitumor response that was maintained over a month after the last treatment. The clinical response was immune-mediated because adoptive transfer of Tregs led to a complete abrogation of the therapeutic effects of immunotoxin treatment. Further, Treg down-modulation was accompanied by increased Ag-specific immunity against the neu protein, a self Ag. These results suggest that Tregs play a major role in preventing an effective endogenous immune response against breast cancer and that depletion of Tregs, without any additional immunotherapy, may mediate a significant antitumor response.

Abstract Through their differential interactions with B lymphocyte stimulator (BLyS) and a proliferation-inducing ligand (APRIL), the three BLyS family receptors play central roles in B cell survival and differentiation. Recent evidence indicates BLyS receptor levels shift following BCR ligation, suggesting that activation cues can alter overall BLyS receptor profiles and thus ligand sensitivity. In this study, we show that TLR stimuli also alter BLyS receptor expression, but in contrast to BCR ligation, TLR9 and TLR4 signals, preferentially increase transmembrane activator calcium modulator and cyclophilin ligand interactor (TACI) expression. Although both of these TLRs act through MyD88-dependent mechanisms to increase TACI expression, they differ in terms of their downstream mediators and the B cell subset affected. Surprisingly, only TLR4 relies on c-Rel and p50 to augment TACI expression, whereas TLR9 does not. Furthermore, although all follicular and marginal zone B cells up-regulate TACI in response to TLR9 stimulation, only marginal zone B cells and a subset of follicular B cells respond to TLR4. Finally, we find that both BLyS and APRIL enhance viability among quiescent and BCR-stimulated B cells. However, although BLyS enhances viability among TLR stimulated B cells, APRIL does not, suggesting that TACI but not BLyS receptor 3 may share survival promoting pathways with TLRs.