Successful voriconazole treatment of invasive pulmonary aspergillosis in a patient with acute biphenotypic leukemia

A 23-year old woman with acute biphenotypic leukemia (ABL) complained of chest pain with cough, high fever and hemoptysis during induction chemotherapy, although she had been treated with anti-biotics and micafungin. We made a clinical diagnosis of invasive pulmonary aspergillosis (IPA) based on a consolidation in the right upper lung field on a chest radiograph as well as a high level of serum beta-D-glucan (with no evidence of tuberculosis and candidiasis). We changed her treatment from micafungin to voriconazole. Later, we discovered an air-crescent sign by CT scan that supported the diagnosis of IPA. Following voriconazole treatment, clinical symptoms ceased and abnormal chest shadows improved gradually and concurrently with a recovery of neutrophils. IPA must be considered in immunocompromised patients with pulmonary infiltrates who do not respond to broad-spectrum antibiotics. Serological tests and CT findings can aid in early diagnosis of IPA, which, along with treatment for IPA, will improve clinical outcomes.</p

Efficient Drug Delivery of Paclitaxel Glycoside: A Novel Solubility Gradient Encapsulation into Liposomes Coupled with Immunoliposomes Preparation

Although the encapsulation of paclitaxel into liposomes has been extensively studied, its significant hydrophobic and uncharged character has generated substantial difficulties concerning its efficient encapsulation into the inner water core of liposomes. We found that a more hydrophilic paclitaxel molecule, 7-glucosyloxyacetylpaclitaxel, retained tubulin polymerization stabilization activity. The hydrophilic nature of 7-glucosyloxyacetylpaclitaxel allowed its efficient encapsulation into the inner water core of liposomes, which was successfully accomplished using a remote loading method with a solubility gradient between 40% ethylene glycol and Cremophor EL/ethanol in PBS. Trastuzumab was then conjugated onto the surface of liposomes as immunoliposomes to selectively target human epidermal growth factor receptor-2 (HER2)-overexpressing cancer cells. In vitro cytotoxicity assays revealed that the immunoliposomes enhanced the toxicity of 7-glucosyloxyacetylpaclitaxel in HER2-overexpressing cancer cells and showed more rapid suppression of cell growth. The immunoliposomes strongly inhibited the tumor growth of HT-29 cells xenografted in nude mice. Notably, mice survived when treated with the immunoliposomes formulation, even when administered at a lethal dose of 7-glucosyloxyacetylpaclitaxel in vivo. This data successfully demonstrates immunoliposomes as a promising candidate for the efficient delivery of paclitaxel glycoside

A Model of Cancer Stem Cells Derived from Mouse Induced Pluripotent Stem Cells

Cancer stem cells (CSCs) are capable of continuous proliferation and self-renewal and are proposed to play significant roles in oncogenesis, tumor growth, metastasis and cancer recurrence. CSCs are considered derived from normal stem cells affected by the tumor microenvironment although the mechanism of development is not clear yet. In 2007, Yamanaka's group succeeded in generating Nanog mouse induced pluripotent stem (miPS) cells, in which green fluorescent protein (GFP) has been inserted into the 5′-untranslated region of the Nanog gene. Usually, iPS cells, just like embryonic stem cells, are considered to be induced into progenitor cells, which differentiate into various normal phenotypes depending on the normal niche. We hypothesized that CSCs could be derived from Nanog miPS cells in the conditioned culture medium of cancer cell lines, which is a mimic of carcinoma microenvironment. As a result, the Nanog miPS cells treated with the conditioned medium of mouse Lewis lung carcinoma acquired characteristics of CSCs, in that they formed spheroids expressing GFP in suspension culture, and had a high tumorigenicity in Balb/c nude mice exhibiting angiogenesis in vivo. In addition, these iPS-derived CSCs had a capacity of self-renewal and expressed the marker genes, Nanog, Rex1, Eras, Esg1 and Cripto, associated with stem cell properties and an undifferentiated state. Thus we concluded that a model of CSCs was originally developed from miPS cells and proposed the conditioned culture medium of cancer cell lines might perform as niche for producing CSCs. The model of CSCs and the procedure of their establishment will help study the genetic alterations and the secreted factors in the tumor microenvironment which convert miPS cells to CSCs. Furthermore, the identification of potentially bona fide markers of CSCs, which will help the development of novel anti-cancer therapies, might be possible though the CSC model

A cancer stem cell model as the point of origin of cancer-associated fibroblasts in tumor microenvironment

Cancer-associated fibroblasts (CAFs) are one of the most prominent cell types in the stromal compartment of the tumor microenvironment. CAFs support multiple aspects of cancer progression, including tumor initiation, invasion, and metastasis. The heterogeneous nature of the stromal microenvironment is attributed to the multiple sources from which the cells in this compartment originate. The present study provides the first evidence that cancer stem cells (CSCs) are one of the key sources of CAFs in the tumor niche. We generated CSC-like cells by treating mouse induced pluripotent stem cells with conditioned medium from breast cancer cell lines. The resulting cell population expressed both CSC and pluripotency markers, and the sphere-forming CSC-like cells formed subcutaneous tumors in nude mice. Intriguingly, these CSC-like cells always formed heterogeneous populations surrounded by myofibroblast-like cells. Based on this observation, we hypothesized that CSCs could be the source of the CAFs that support tumor maintenance and survival. To address this hypothesis, we induced the differentiation of spheres and purified the myofibroblast-like cells. The resulting cells exhibited a CAF-like phenotype, suggesting that they had differentiated into the subpopulations of cells that support CSC self-renewal. These findings provide novel insights into the dynamic interplay between various microenvironmental factors and CAFs in the CSC niche

HSP‐enriched properties of extracellular vesicles involve survival of metastatic oral cancer cells

Cancer cells often secrete extracellular vesicles (EVs) that carry heat shock proteins (HSPs) with roles in tumor progression. Oral squamous cell carcinoma (OSCC) belongs to head and neck cancers (HNC) whose lymph-node-metastases often lead to poor prognosis. We have examined the EV proteome of OSCC cells and found abundant secretion of HSP90-enriched EVs in lymph-node-metastatic OSCC cells. Double knockdown of HSP90α and HSP90β, using small interfering RNA significantly reduced the survival of the metastatic OSCC cells, although single knockdown of each HSP90 was ineffective. Elevated expression of these HSP90 family members was found to correlate with poor prognosis of HNC cases. Thus, elevated HSP90 levels in secreted vesicles are potential prognostic biomarkers and therapeutic targets in metastatic OSCC

Effects of raloxifene on the production of cytokines in stimulated whole blood in ex vivo and in vitro studies

Purpose : The aims of this study were to determine the effects of raloxifene therapy on production of cytokines and in vitro effects of raloxifene on production of cytokines by whole blood cultures. Methods :We obtained samples of peripheral blood from 6 postmenopausal women with osteopenia at baseline and after 3 and 6 months of raloxifene therapy and 10 postmenopausal women who did not receive raloxifene therapy. Whole blood from raloxifene-treated women was stimulated with lipopolysaccharide (LPS) or phytohemeagglutinin (PHA). Whole blood from postmenopausal women who were not treated with raloxifene was preincubated with raloxifene at concentrations of 10-10-10-7 M and then stimulated with LPS or PHA. Concentrations of IL-1β, IL-4, IL-6, IL-12p40, IL-12p70, TNF-α and IFN-γ in the supernatant were measured by respective ELISAs. Results : In ex vivo cultures, raloxifene therapy inhibited LPS-stimulated production of IL-1β, IL-6, IL-12p40, IL-12p70 and TNF-α, but not PHA-stimulated production of IL-4 and IFN-γ. In in vitro cultures, raloxifene at a concentration (10-9 M) inhibited LPS-stimulated production of IL-1β, IL-6 and IL-12p40 and PHA-stimulated production of IFN-γ. Conclusions : Raloxifene therapy decreases the production of IL-1β, IL-6, IL-12 and TNF-α but not that of IL-4 and IFN-γ, suggesting that modulation of cytokines could play a role in the mechanisms of the osteoprotective effect of raloxifene

A Novel Combination Cancer Therapy with Iron Chelator Targeting Cancer Stem Cells via Suppressing Stemness

Excess iron causes cancer and is thought to be related to carcinogenesis and cancer progression including stemness, but the details remain unclear. Here, we hypothesized that stemness in cancer is related to iron metabolism and that regulating iron metabolism in cancer stem cells (CSCs) may be a novel therapy. In this study, we used murine induced pluripotent stem cells that expressed specific stem cell genes such as Nanog, Oct3/4, Sox2, Klf4, and c-Myc, and two human cancer cell lines with similar stem cell gene expression. Deferasirox, an orally available iron chelator, suppressed expression of stemness markers and spherogenesis of cells with high stemness status in vitro. Combination therapy had a marked antitumor effect compared with deferasirox or cisplatin alone. Iron metabolism appears important for maintenance of stemness in CSCs. An iron chelator combined with chemotherapy may be a novel approach via suppressing stemness for CSC targeted therapy