Autophagy promotes T-cell survival through degradation of proteins of the cell death machinery

Autophagy is implicated in regulating cell death in activated T cells, but the underlying mechanism is unclear. Here, we show that inhibition of autophagy via Beclin 1 gene deletion in T cells leads to rampant apoptosis in these cells upon TCR stimulation. Beclin 1-deficient mice fail to mount autoreactive T-cell responses and are resistant to experimental autoimmune encephalomyelitis. Compared with Th17 cells, Th1 cells are much more susceptible to cell death upon Beclin 1 deletion. Cell death proteins are highly increased in Beclin 1-deficient T cells and inhibition of caspases and genetic deletion of Bim reverse apoptosis. In addition, p62/sequestosome 1 binds to caspase-8 but does not control levels of procaspase-8 or other cell death-related proteins. These results establish a direct role of autophagy in inhibiting the programmed cell death through degradation of apoptosis proteins in activated T cells.

Enhanced chemosensitivity to CPT-11 in colorectal carcinoma xenografts by small hairpin RNA interference targeting PLK1

Commonly used drugs for the treatment of colon{} cancer patients like CPT-11 shows severe side effects or induces resistance in clinical settings. Thus, we analyzed a combination of PLK1 (polo-like kinase 1)-specific short hair RNA (shRNA), a potent tool to destroy mitosis in cancer cells, together with CPT-11 to enhance drug sensitivity. Cellular proliferation and apoptosis were determined in SW620 colorectal carcinoma cells. Knockdown of cellular PLK1 led to the decreased mRNA and PLK1 protein in RT-PCR and western blot assay. The viability declined (p<0.001) in MTT assay and colony formation assay, and the number of apoptotic cells was clearly increased (p<0.01) in flow cytometric analysis and Hoechst 33258 staining compared with control cells after incubation with PLK1-specific shRNA and SN-38. We found the level of cleaved PARP was also increased in vitro. In vivo, employment of shRNA targeting PLK1 improved the sensitivity to treat SW620 nude mouse model toward CPT-11. The combination therapy inhibited cellular proliferation and promoted apoptosis observed at the percentage of PCNA and caspase3 by immunohistochemistry, accompanied with TUNEL assay. As we expect, the combination treatment delayed tumor growth (p<0.01) and simultaneously reduced tumor weight (p<0.01) compared with control group. Taken together, combination of PLK1-specific shRNA interference with low-dose CPT-11 triggered a antitumor efficacy and represented a potential strategy to treat colon cancer.

Trichosanthin-stimulated dendritic cells induce a type 2 helper T lymphocyte response through the OX40 ligand

BACKGROUND

Trichosanthin (TCS) induces a type 2 helper T lymphocyte (T(H)2) immune response that leads to the production of TCS-specific immunoglobulin (Ig) E and a subsequent allergic reaction in vivo. However, events immediately following treatment with TCS are poorly understood.

OBJECTIVE

We aimed to investigate whether dendritic cells (DCs) are the initial mediators of T(H)2 cell polarization induced by TCS and to investigate potential causative mechanisms

METHODS

DCs were cultured from purified human peripheral monocytes in the presence of granulocyte-macrophage colony-stimulating factor and interleukin (IL) 4. Flow cytometry was used to analyze cell surface antigen, intracellular cytokines, DC endocytic capacity, and apoptosis. The transcriptional profile for 120 genes in DCs was detected using oligonucleotide microarray analysis.

RESULTS

TCS exerted a cytotoxic effect on DCs in a concentration-dependent manner. Although TCS alone did not induce full maturation of DC, it did so in the presence of tumor necrosis factor alpha and IL-1beta in vitro. TCS-stimulated DCs induced a decreased ratio of T(H)1/T(H)2 cells derived from naïve T cells and showed selective expression of OX40 ligand (OX40L) at both mRNA and protein levels. This induction was partially blocked by anti-OX40L antibody.

CONCLUSION

Our results imply that TCS-stimulated DCs polarize the development of T(H)2 cells partially by means of the OX40L signal. Modulation of these DC will favor the alleviation of TCS-induced allergy.

The role of ClpP in protein expression of Streptococcus pneumoniae

Previous reports suggest that ClpP proteolytic activity is important not only for cell physiology but also for regulation of virulence properties of Streptococcus pneumoniae (S. pneumoniae). In order to get a more comprehensive picture of the role of ClpP protease on protein expression in S. pneumoniae D39 and how it relates to physiology and virulence, a clpP mutant strain was constructed in S. pneumoniae D39, and global proteome expression was studied by 2-dimensional electrophoresis and matrix-assisted laser desorption-ionization-time of flight mass spectrometry. We report here that clpP deletion affects the expression of proteins which are involved in the general stress response, nucleotide metabolism, energy metabolism, and proteins metabolism. These provide clues for understanding the role of ClpP in the physiology and pathogenesis of pneumococcus.

Severe diffuse non-scarring hair loss in systemic lupus erythematosus - clinical and histopathological analysis of four cases

BACKGROUND

Although diffuse non-scarring hair loss been found common in systemic lupus erythematosus (SLE), study that conduted on the severe type has been scarce.

OBJECTIVE

This study aims to explore the dermoscopic and pathological features of severe diffuse hair loss in SLE.

METHOD

Data including clinico-laboratory, dermoscopic and histopathological findings of four patients with SLE with severe diffuse hair loss were analysed retrospectively.

RESULTS

All four patients were women aged 41, 39, 14 and 48 with complaints of hair loss involving 55%, 100%, 60% and 55% of their scalp respectively. Common clinical findings observed in the patients were sparse scalp hair with clusters of newly regrown hair. Scalp dermoscopy showed scaling, perifollicular telangiectasia, increased numbers of short vellus hairs, focal atrichia and decreased hair shaft pigmentation. Scalp tissue histopathology revealed typical changes of SLE such as epidermal atrophy with focal liquefaction, degeneration of the basement membrane zone, pigment incontinence, mild focal perivascular and perifollicular lymphocytic infiltrates and deposition of immunoglobulins at the dermal-epidermal junction. Treatment and improvement in SLE disease activity indices had a favourable impact on hair regrowth.

CONCLUSION

The severe type of hair loss in patient with SLE presents a unique set of clinical, dermoscopic and histopathological features.

Nanometer-scale lithography on microscopically clean graphene

Focused-electron-beam-induced deposition, or FEBID, enables the fabrication of patterns with sub-10 nm resolution. The initial stages of metal deposition by FEBID are still not fundamentally well understood. For these investigations, graphene, a one-atom-thick sheet of carbon atoms in a hexagonal lattice, is ideal as the substrate for FEBID writing. In this paper, we have used exfoliated few-layer graphene as a support to study the early growth phase of focused-electron-beam-induced deposition and to write patterns with dimensions between 0.6 and 5 nm. The results obtained here are compared to the deposition behavior on amorphous materials. Prior to the deposition experiment, the few-layer graphene was cleaned. Typically, it is observed in electron microscope images that areas of microscopically clean graphene are surrounded by areas with amorphous material. We present a method to remove the amorphous material in order to obtain large areas of microscopically clean graphene flakes. After cleaning, W(CO)(6) was used as the precursor to study the early growth phase of FEBID deposits. It was observed that preferential adsorption of the precursor molecules on step edges and adsorbates plays a key role in the deposition on cleaned few-layer graphene.

P2-09-14: Evaluation of Angiogenesis Using Synchrotron Radiation in Xenograft Mouse Models of Breast Cancer

Visualization of microvasculatures is an important step in understanding the mechanism of early vessel disorders in breast cancer and developing effective therapeutic strategies. However, quantitative evaluation of breast cancer angiogenesis using immunohistochemistry has been limited in generating detailed and reproducible data. To analyze the diversification of angiogenesis in the development of tumor growth and evaluate anti-vascular effects of Avastin, a new method of microvascular imaging was introduced in this paper. We used New X-ray microangiography and third-generation synchrotron radiation-based micro-computed tomography (SR micro-CT) to investigate the structures and density of microvessels at each stage of xenograft mouse models that were created by inoculation with MDA-MB-231HM cells (one breast cancer cell line with high metastasis potential). Barium Sulfate Nanoparticles, was used as a blood vessels contrast agent through left cardiac ventricle. Three dimensional structures of microvessels were displayed with a high spatial image resolution at around 20–30 μm. The density of microvessles was significantly reduced from the third week in mouse xenograft models. This observation with SR micro-CT was consistent with the results analyzed by immunohistochemical techniques. In addition, human breast cancer-bearing mice were treated site-specifically with humanized monoclonal antibody (Avastin) that targets all isoforms of VEGF-A. Tumor volume and the density of angiogenesis were significantly reduced in xenograft mouse models of breast cancer treated with avastin when compared with untreated mice as assessed by SR micro-CT. Specifically, the density of smaller vessels (di&lt;50μm) was decreased significantly while the density of larger vessels was little changed in the Avastin-treated mice. Therefore, synchrotron radiation technique is a novel method for investigating breast cancer angiogenesis, and this might be considered as an additional complementary tool for more precise quantification of angiogenesis.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-09-14.

P4-01-14: Fulvestrant Regulates Epidermal Growth Factor (EGF) Ligands and Induces EGF Receptor Activation in MCF-7 Breast Cancer Cells

Selective Estrogen Receptor Modulators (SERMs) 4 Hydroxy Tamoxifen (4-HT) and fulvestrant (fulv) inhibit estrogen receptor a (ER) positive breast cancer growth. We have observed that treatment (24 to 48 hours) of fulv in MCF-7 cells induced a 190kDa tyrosine phosphorylated band, which was blocked by EGFR and HER-2 tyrosine kinase inhibitors erlotinib and lapatinib. Immunoprecipitation showed EGFR, HER-2, and HER-3 were all phosphorylated after fulv treatment. 4-HT and estradiol did not cause this phosphorylation. No changes in receptor level after fulv treatment were noted. Downstream MAPK signaling was also blocked by erlotinib and lapatinib. Fulv induced activation of EGFR was ER dependent, since fulv treatment in C4-12, an ER negative cell line derived from MCF-7 cells, did not induce EGFR activation. Co-treatment with estradiol and fulv prevented EGFR activation. To explore the possibility that fulv enhanced ligand expression, we collected conditioned media (CM) from MCF-7 cells after 48 hours of treatment. pEGFR was lost when CM was removed, but recurred within 30 minutes. Cycloheximide abolished the ability of fulv to activate EGFR suggesting autorcine production of EGFR ligands was induced by fulv. To detect specific EGFR ligands, we used qPCR to measure various EGFR ligand mRNA levels in MCF-7 and C4-12 cell at 1, 4, 24 and 48 hours after fulv treatment. TGF-α and HB-EGF mRNAs were upregulated over 48 hours, which correlated well with pEGFR activation. 4-HT did not affect mRNA levels of these ligands. In contrast, amphiregulin (AREG) mRNA levels were substantially reduced 48 hours after fulv treatment. A similar trend was seen for AREG mRNA levels in 4HT treated cells but to a much lesser extent. There was no change in any EGFR ligand mRNA levels in ER negative C4-12 cells. These qPCR data suggested differential regulation of EGFR ligands by fulv treatment contributed to EGFR family member activation and was dependent on ER expression. Upon fulv treatment, levels of ER were diminished with decreased detection of S167 and S118 ER phosphorylation sites. Monolayer cell growth analysis showed that while fulv treatment in SFM reduced MCF-7 cell numbers compared to control treatment, erlotinib plus fulv significantly reduced cell numbers below the level of cells maintained in fulv alone. In conclusion, we show that fulv, but not E2 or 4-HT, activates EGFR family members accompanied by upregulation of ligands. Since SERM resistance has been associated with EGFR family member activation, differential control of EGFR ligand gene expression by ER may contribute to the development of fulvestrant resistance in breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-01-14.

P4-07-03: Identification of Triple-Negative Primary Breast Cancer Xenograft Models with High Numbers of Circulating and Disseminated Tumor Cells

Background: Primary breast cancer xenografts, in which tumors are grown directly from patients and which maintain their original genotype and phenotype, have the potential to facilitate the study of tumor biology and progression. These models can also be instrumental in the discovery of novel therapeutic targets especially for the triple-negative (ER-, PR- and HER2−negative, TN) breast cancer. TN breast cancer is associated with high numbers of circulating and disseminated tumor cells (CTCs and DTCs), which predict poor outcome in patients and may play a role in tumor progression. However, isolation and detection of human CTCs and DTCs in these xenograft models have been challenging even with EpCAM-based enrichment methods. The goal of this study was to determine if CTCs and DTCs could be identified using human pan-CK staining in a panel of triple-negative primary breast cancer xenograft lines, which could then be employed to study the biology of these cells and to test novel therapies.

Methods: We screened 13 stable primary transplantable xenograft lines (1-6 mice per line), established by directly transplanting ethnically diverse triple-negative tumor samples into the epithelium-free mammary fat pads of SCID/Beige mice, for the presence of CTCs and DTCs. The triple-negative status was maintained in these xenograft lines over serial passages. To detect CTCs, peripheral blood mononuclear cells (PBMCs) were isolated from the blood collected from the inferior vena cava either by Ficoll gradient or RBC lysis, with a typical yield of 500,000 PBMCs in 500 μl of blood. Subsequently, PBMCs were immunostained for the presence of CTCs, which were defined as the cells positive for cytoplasmic human pan-cytokeratin staining and nuclear (DAPI/hematoxylin) counter stain. We also flushed the femurs and tibias of 7 xenograft lines to harvest bone marrow cells (BMCs) for the detection of DTCs using the same staining procedure. A xenograft line was considered positive for CTCs or DTCs if they were detected in at least 25% of mice. The presence of lung metastases was assessed in all the xenograft lines by histological examination.

Results: We detected CTCs (range: 1–128/20,000 PBMCs) in 6 out of 13 xenograft lines (46%) and DTCs (range: 1–21/20,000 BMCs) in 5 out of 7 (71%) lines. Interestingly, 4 of the 5 DTC-positive lines also had detectable CTCs. High numbers of CTCs (&gt;20/20,000 PBMCs) were found in 3 xenograft lines, one of which also had high numbers of DTCs (&gt;20/20,000 BMCs). No human pan-CK+ cells were detected in PBMCs and/or BMCs from 5 control mice without tumors. Among 13 xenograft lines, lung metastases were found in 5 lines (38%), of which 3 had detectable CTCs or DTCs. Of the 3 xenograft lines containing high CTCs and/or DTCs, 2 had lung metastases.

Conclusion: In summary, human pan-CK staining can effectively detect CTCs and DTCs in isolated PBMCs and BMCs of mice bearing triple-negative primary breast cancer xenografts. These xenograft lines with detectable CTCs and DTCs may represent a valuable preclinical model for detailed characterization of human CTCs and DTCs and for the discovery of new therapeutic targets for the triple-negative breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-07-03.

P5-21-01: A Renewable Tissue Resource of Phenotypically Stable Human Breast Cancer Xenografts for Preclinical Studies

Introduction Translational breast cancer research is hampered severely by difficulties in obtaining and studying primary human breast tissue, and by the lack of in vivo preclinical models that accurately reflect patient tumor biology. These limitations are due, in part, to the fact that traditional immunocompromised mouse models are not generally permissive for growth. We sought to circumvent some of these limitations by transplanting and growing human mammary tumors in the mammary fat pad of SCID/Beige immunocompromised mice in the absence of exogenous human fibroblasts.

Aims and Methods To establish a set of stable human breast cancer xenografts for preclinical studies. Human breast cancer biopsies were received, minced into small fragments and then transplanted directly into “cleared” fat pads of recipient SCID/Beige immunocompromised mice. Transplanted fat pads were checked weekly. After initial tumor was palpated and harvested, tumor fragments were transplanted into new SCID/Beige hosts for subsequent transplant generations. Serial immunohistochemical evaluations were performed to confirm human origin and biomarker status. Analytical flow cytometry for evaluating expression of proposed “cancer stem cell” markers, and gene and protein expression analysis were carried out on all stable lines.

Results and Conclusions Xenograft lines were established directly from breast cancer patient samples, without intervening culture in vitro, using the epithelium-free mammary fat pad as the transplantation site. Of the conditions tested, xenograft take rate was highest in the presence of a low-dose estradiol pellet without exogenous human fibroblasts. Thirty six stably transplantable xenograft lines representing 27 patients were established, using pre-treatment, mid-treatment, and/or post-treatment samples. Most patients yielding xenografts were “triple-negative” (ER-PR-HER2−) (n=21), we were able to establish lines from three ER-PR-HER2+ patients, one ER+PR+HER2−, one ER+PR-HER2−and one “triple-positive” (ER+PR+HER2+) patients. Serially passaged xenografts show phenotypic consistency with the tumor of origin at the histopathology level, and remarkable stability across multiple transplant generations at both the genomic, transcriptomic, and proteomic levels. Of 27 lines evaluated fully, thirteen xenografts showed metastasis to the mouse lung. These models thus serve as a renewable, quality-controlled tissue resource, and should prove useful for preclinical evaluation of experimental therapeutics.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-21-01.

P1-04-09: Biphasic Effects of Docetaxel and Hedgehog Signaling Antagonists on Breast Cancer Tumor-Initiating Cells In Vivo

Recent data suggest the existence of a subset of breast cancer cells variously termed cancer stem cells, tumor-initiating, or tumor-propagating cells, that are capable of self-renewal and of regenerating tumors upon transplantation that are biologically consistent with the tumor of origin. These cells appear to be intrinsically resistant to systemic chemo- and radiation therapies and may therefore be responsible for treatment resistance, and disease recurrence. Several signal transduction networks have been implicated in normal and malignant stem cell self-renewal. These include those of the Hedgehog, Notch, Wnt, EGF, FGF families of ligands. Antagonists of these networks have become attractive targeted therapeutic agents. In this study, we evaluated two different Hedgehog signaling antagonists, one targeting Smoothened (the main membrane effector of activated signaling) and one targeting GLI1/2 (the two transcription factors mediating ligand response), for their ability to shrink patient-derived xenograft tumors and to affect the number or function of breast tumor-initiating cells in vivo. Both antagonists showed little effect as single agents, but could augment tumor shrinkage by docetaxel. However, these effects were only observed in those models showing evidence of canonical SMO/GLI-mediated signaling. In dilutional transplantation assays, both SMO or GLI targeted agents have a biphasic effect on the behavior of the tumor-initiating population such that large cell numbers yielded few tumors while intermediate cell numbers yielded tumors at a comparable rate as controls. These data suggest that combination therapy alters the functional state of stem cells in the context of larger cell numbers rather than targeting the tumor-initiating cell directly. These data therefore have significant relevance for the interpretation of ongoing clinical trials of hedgehog signaling inhibitors in solid tumors, including breast cancer.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-04-09.

P4-01-07: Combining Hedgehog Inhibitor, GDC-0449 with Tamoxifen Overcomes Tamoxifen-Resistance in In-Vitro and In-Vivo Studies of Estrogen-Receptor Positive Breast Cancer

Aims: Approximately 30–40% of patients with estrogen receptor positive (ER+) invasive breast cancer relapse despite targeted endocrine therapy with tamoxifen. Dependency of ER+ breast tumors shifts from estrogen to alternative cell survival mechanisms aberrantly activated over time facilitating drug-resistance and survival. We have identified Hedgehog (Hhg) signaling pathway as one such alternative pathway of survival activated in ER+ tumors that are resistant to tamoxifen. We sought to determine if treating such tumors with Hhg inhibitor and tamoxifen would improve outcomes.

Methods: Using MCF7 cell lines that are either sensitive (parental) or resistant to tamoxifen (4-hydroxy tamoxifen resistant-OHTR) and other ER+ cell lines, expression of Hhg markers (SHH, PTCH, SMO, GLI1, GLI2 and GLI3) and Hhg targets (SNAIL, MYC, BMI1 and FOXM1) was analyzed by Real-time RT-PCR, Western blotting and immunocytochemistry. GLI1 transactivation potential was measured using 8XGLI-Luciferase reporter plasmid. GLI1 was depleted in OHTR and T47D cells using GLI1siRNA. The GLI1 depleted cells were exposed to tamoxifen and assessed for i) cell viability by MTT assay, ii) extent of apoptosis by TUNEL assay and PARP/Caspase cleavage (Western blot), iii) cell cycle profile by flow cytometry and iv) presence of tumor initiating cells (TICs) by mammosphere formation assay. Effect of GDC-0449, a small molecule inhibitor of SMO was tested on OHTR cell induced xenografts in athymic nude mice by monitoring tumor growth and distant metastasis. Correlation of GLI1 expression in primary breast tumor tissues (assessed by immunohistochemistry) and disease-free interval was studied in women enrolled on an ongoing clinical trial (OSU 0483) in premenopausal women with ER+ breast cancer undergoing adjuvant oophorectomy and tamoxifen.

Results: Expression of Hhg signaling molecules and the targets are significantly activated in OHTR cells resistant to 0.5 and 1μM tamoxifen. Serial passage of the resistant cells in mice resulted in aggressive transformation of tumors that micro-metastasized to lung and liver. Concurrent increase in Hhg marker expression, TICs and acquisition of epithelial mesenchymal transition were observed in the cells derived from these tumors. Depletion of GLI1 in OHTR cells resulted in reduced proliferation, colony formation and mammosphere formation and increased apoptosis in presence of tamoxifen. Treatment of OHTR cells with GDC-0449 and tamoxifen inhibited cell proliferation in vitro and supressed tumor growth and distant metastasis of tamoxifen resistant xenografts in mice. Primary human breast tumors expressing higher level of GLI1 demonstrated a trend towards increased risk of recurrence (p= 0.08) after tamoxifen therapy.

Conclusions: Our work has demonstrated for the first time that activated Hhg signaling is an alternate survival mechanism for tamoxifen resistant breast cancer. Furthermore, targeting these tumors with a combination of tamoxifen and anti-Hhg therapy inhibited tumor growth and development of distant metastases demonstrating efficacy of this approach. Clinical trials using this combination in patients with advanced ER+ breast cancer are warranted and are under development.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-01-07.

Isolation and characterization of nucleotide-binding site and C-terminal leucine-rich repeat-resistance gene candidates in bananas

Commercial banana varieties are highly susceptible to fungal pathogens, as well as bacterial pathogens, nematodes, viruses, and insect pests. The largest known family of plant resistance genes encodes proteins with nucleotide-binding site (NBS) and C-terminal leucine-rich repeat (LRR) domains. Conserved motifs in such genes in diverse plant species offer a means for the isolation of candidate genes in banana that may be involved in plant defense. Six degenerate PCR primers were designed to target NBS and additional domains were tested on commercial banana species Musa acuminata subsp malaccensis and the Musa AAB Group propagated in vitro and plants maintained in a greenhouse. Total DNA was isolated by a modified CTAB extraction technique. Four resistance gene analogs were amplified and deposited in GenBank and assigned numbers HQ199833-HQ199836. The predicted amino acid sequences compared to the amino acid sequences of known resistance genes (MRGL1, MRGL2, MRGL3, and MRGL4) revealed significant sequence similarity. The presence of consensus domains, namely kinase-1a, kinase-2 and hydrophobic domain, provided evidence that the cloned sequences belong to the typical non-Toll/interleukin-1 receptor-like domain NBS-LRR gene family.

High glucose-induced expression of inflammatory cytokines and reactive oxygen species in cultured astrocytes

Astrocyte activation plays important roles both in physiological and pathological process in the CNS. In the latter, the process is further aggravated by hyperglycemia, leading to diabetes complications of CNS. We report here that high glucose (HG) treatment stimulated astrocytic morphological alteration coupled with changes in glial fibrillary acidic protein (GFAP) and vimentin expression. Additionally, HG upregulated the expression of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), interleukin-1β (IL-1β), interleukin-4 (IL-4), and vascular endothelial growth factor (VEGF); however, its effects on transforming growth factor-β (TGF-β) expression were not evident. HG treatment induced increased production of reactive oxygen species (ROS) as well as activation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) and signal transducer and activator transcription 3 (STAT 3). HG-induced expression of TNF-α, IL-6, IL-1β, IL-4, and VEGF was blocked by ROS scavenger and inhibitors specific for NF-κB and STAT 3, respectively. The results suggest that the aforementioned multiple inflammatory cytokines and mediators that may be linked to the pathogenesis of the diabetes complications of CNS are induced by HG via the key signaling pathways.

Bronchopulmonary infection with Lophomonas blattarum: a case report and literature review

Human infection with Lophomonas blattarum is extremely rare. The clinical manifestations of 45 cases of bronchopulmonary L. blattarum infection occurring in China, including one case diagnosed and treated at the authors' hospital, are described. The most common manifestations included fever, cough with expectoration, chest stuffiness or shortness of breath, bronchiectasis and pulmonary abscess. A course of metronidazole treatment lasting 14-38 days was effective in controlling the disease. The diagnosis of L. blattarum infection should be based on one or more of bronchoscopic brush smear, bronchoscopic biopsy smear and bronchoalveolar lavage.

Comparison of entecavir and lamivudine in preventing hepatitis B reactivation in lymphoma patients during chemotherapy

During chemotherapy for lymphoma, the administration of cytotoxic agents and rituximab often results in hepatitis B reactivation (incidence, 14-72%). This study was designed to compare the efficacy of entecavir and lamivudine in preventing hepatitis B reactivation in lymphoma patients. Between January 2007 and February 2009, patients treated in four hospitals in China were screened to identify those most appropriate for analysis. These patients received either entecavir or lamivudine during chemotherapy and for 6 months after completion of chemotherapy. A total of 34 patients received entecavir and 89 patients received lamivudine. Compared with the lamivudine group, the entecavir group had significantly lower rates of hepatitis (5.9 vs 27.0%, P = 0.007), hepatitis B reactivation (0 vs 12.4%, P = 0.024) and disruption of chemotherapy (5.9 vs 20.2%, P = 0.042). All patients with hepatitis B reactivation had B-cell non-Hodgkin's lymphoma (stage III-IV). In lymphoma patients under chemotherapy treatment, entecavir is more effective than lamivudine in preventing hepatitis B reactivation. For patients with advanced stage disease, entecavir should be considered the primary preventive therapy.