Two Cell-Bound Keratinases of Trichophyton Mentagrophytes

Two cell-bound keratinases, II and III, of Trichophyton mentagrophytes were extracted from mycelium and purified. The purified keratinases, II and III, had a specific keratinolytic activity of 36.4 and 39.4 KU/mg respectively. The molecular weights of keratinases II and III were 440,000 and 20,300 respectively. Immunodiffusion analysis showed that these two cell-bound keratinases, II and III, were not identical to each other nor to extracellular keratinase I of the same species

Smoking, Green Tea Consumption, Genetic Polymorphisms in the Insulin-Like Growth Factors and Lung Cancer Risk

Insulin-like growth factors (IGFs) are mediators of growth hormones; they have an influence on cell proliferation and differentiation. In addition, IGF-binding protein (IGFBP)-3 could suppress the mitogenic action of IGFs. Interestingly, tea polyphenols could substantially reduce IGF1 and increase IGFBP3. In this study, we evaluated the effects of smoking, green tea consumption, as well as IGF1, IGF2, and IGFBP3 polymorphisms, on lung cancer risk. Questionnaires were administered to obtain the subjects' characteristics, including smoking habits and green tea consumption from 170 primary lung cancer cases and 340 healthy controls. Genotypes for IGF1, IGF2, and IGFBP3 were identified by polymerase chain reaction. Lung cancer cases had a higher proportion of smoking, green tea consumption of less than one cup per day, exposure to cooking fumes, and family history of lung cancer than controls. After adjusting the confounding effect, an elevated risk was observed in smokers who never drank green tea, as compared to smokers who drank green tea more than one cup per day (odds ratio (OR) = 13.16, 95% confidence interval (CI) = 2.96–58.51). Interaction between smoking and green tea consumption on lung cancer risk was also observed. Among green tea drinkers who drank more than one cup per day, IGF1 (CA)19/(CA)19 and (CA)19/X genotypes carriers had a significantly reduced risk of lung cancer (OR = 0.06, 95% CI = 0.01–0.44) compared with IGF1 X/X carriers. Smoking-induced pulmonary carcinogenesis could be modulated by green tea consumption and their growth factor environment

Malignant phyllodes tumors display mesenchymal stem cell features and aldehyde dehydrogenase/disialoganglioside identify their tumor stem cells

INTRODUCTION: Although breast phyllodes tumors are rare, there is no effective therapy other than surgery. Little is known about their tumor biology. A malignant phyllodes tumor contains heterologous stromal elements, and can transform into rhabdomyosarcoma, liposarcoma and osteosarcoma. These versatile properties prompted us to explore their possible relationship to mesenchymal stem cells (MSCs) and to search for the presence of cancer stem cells (CSCs) in phyllodes tumors. METHODS: Paraffin sections of malignant phyllodes tumors were examined for various markers by immunohistochemical staining. Xenografts of human primary phyllodes tumors were established by injecting freshly isolated tumor cells into the mammary fat pad of non-obese diabetic-severe combined immunodeficient (NOD-SCID) mice. To search for CSCs, xenografted tumor cells were sorted into various subpopulations by flow cytometry and examined for their in vitro mammosphere forming capacity, in vivo tumorigenicity in NOD-SCID mice and their ability to undergo differentiation. RESULTS: Immunohistochemical analysis revealed the expression of the following 10 markers: CD44, CD29, CD106, CD166, CD105, CD90, disialoganglioside (GD2), CD117, Aldehyde dehydrogenase 1 (ALDH), and Oct-4, and 7 clinically relevant markers (CD10, CD34, p53, p63, Ki-67, Bcl-2, vimentin, and Globo H) in all 51 malignant phyllodes tumors examined, albeit to different extents. Four xenografts were successfully established from human primary phyllodes tumors. In vitro, ALDH(+) cells sorted from xenografts displayed approximately 10-fold greater mammosphere-forming capacity than ALDH(-) cells. GD2(+) cells showed a 3.9-fold greater capacity than GD2(-) cells. ALDH(+)/GD2(+)cells displayed 12.8-fold greater mammosphere forming ability than ALDH(-)/GD2(-) cells. In vivo, the tumor-initiating frequency of ALDH(+)/GD2(+) cells were up to 33-fold higher than that of ALDH(+) cells, with as few as 50 ALDH(+)/GD2(+) cells being sufficient for engraftment. Moreover, we provided the first evidence for the induction of ALDH(+)/GD2(+) cells to differentiate into neural cells of various lineages, along with the observation of neural differentiation in clinical specimens and xenografts of malignant phyllodes tumors. ALDH(+) or ALDH(+)/GD2(+) cells could also be induced to differentiate into adipocytes, osteocytes or chondrocytes. CONCLUSIONS: Our findings revealed that malignant phyllodes tumors possessed many characteristics of MSC, and their CSCs were enriched in ALDH(+) and ALDH(+)/GD2(+) subpopulations

C. elegans EIF-3.K Promotes Programmed Cell Death through CED-3 Caspase

Programmed cell death (apoptosis) is essential for the development and homeostasis of metazoans. The central step in the execution of programmed cell death is the activation of caspases. In C. elegans, the core cell death regulators EGL-1(a BH3 domain-containing protein), CED-9 (Bcl-2), and CED-4 (Apaf-1) act in an inhibitory cascade to activate the CED-3 caspase. Here we have identified an additional component eif-3.K (eukaryotic translation initiation factor 3 subunit k) that acts upstream of ced-3 to promote programmed cell death. The loss of eif-3.K reduced cell deaths in both somatic and germ cells, whereas the overexpression of eif-3.K resulted in a slight but significant increase in cell death. Using a cell-specific promoter, we show that eif-3.K promotes cell death in a cell-autonomous manner. In addition, the loss of eif-3.K significantly suppressed cell death-induced through the overexpression of ced-4, but not ced-3, indicating a distinct requirement for eif-3.K in apoptosis. Reciprocally, a loss of ced-3 suppressed cell death induced by the overexpression of eif-3.K. These results indicate that eif-3.K requires ced-3 to promote programmed cell death and that eif-3.K acts upstream of ced-3 to promote this process. The EIF-3.K protein is ubiquitously expressed in embryos and larvae and localizes to the cytoplasm. A structure-function analysis revealed that the 61 amino acid long WH domain of EIF-3.K, potentially involved in protein-DNA/RNA interactions, is both necessary and sufficient for the cell death-promoting activity of EIF-3.K. Because human eIF3k was able to partially substitute for C. elegans eif-3.K in the promotion of cell death, this WH domain-dependent EIF-3.K-mediated cell death process has potentially been conserved throughout evolution

Antimitotic Effects of Hydroxyurea and Its Derivatives: Structure-Activity Relationships

A total of 25 hydroxyurea derivatives have been screened on mouse vaginal mucosa for antimitotic effect. Antimitotic properties are preserved in derivatives where a methyl or ethyl group is substituted for hydrogen at position 1 or a method group at position 3. Higher alkyl and carbonyl groups at position 1 or 3 are correlated with loss of antimitotic activity. Loss of antimitotic property is interpretable on the basis of steric and inductive-effects. The hydroxyl proton may not be substituted by an alkyl group but can be replaced by labile substituents such as carbamoyl or trimethylsilyl which permit formation of hydroxyurea itself in vivo

3D Z-string: A new knowledge structure to represent spatio-temporal relations between objects in a video

Abstract In this paper, we propose a new knowledge structure called 3D Z-string, extended from the 2D Z-string, to represent the spatial and temporal relations between objects in a video and to keep track of the motions and size changes of the objects. Since there are no cuttings between objects in the 3D Z-string, the integrity of objects is preserved. The string generation and video reconstruction algorithms for the 3D Z-string representation of video objects are also developed. The string generated by the string generation algorithm is unique for a given video and the video reconstructed from a given 3D Z-string is unique too. The experimental results show that the 3D Z-string is more compact and efficient than the 3D C-string in terms of storage space and execution time

NF-κB is activated in CD4+ iNKT cells by sickle cell disease and mediates rapid induction of adenosine A2A receptors.

Reperfusion injury following tissue ischemia occurs as a consequence of vaso-occlusion that is initiated by activation of invariant natural killer T (iNKT) cells. Sickle cell disease (SDC) results in widely disseminated microvascular ischemia and reperfusion injury as a result of vaso-occlusion by rigid and adhesive sickle red blood cells. In mice, iNKT cell activation requires NF-κB signaling and can be inhibited by the activation of anti-inflammatory adenosine A2A receptors (A2ARs). Human iNKT cells are divided into subsets of CD4+ and CD4- cells. In this study we found that human CD4+ iNKT cells, but not CD4- cells undergo rapid NF-κB activation (phosphorylation of NF-κB on p65) and induction of A2ARs (detected with a monoclonal antibody 7F6-G5-A2) during SCD painful vaso-occlusive crises. These findings indicate that SCD primarily activates the CD4+ subset of iNKT cells. Activation of NF-κB and induction of A2ARs is concordant, i.e. only CD4+ iNKT cells with activated NF-κB expressed high levels of A2ARs. iNKT cells that are not activated during pVOC express low levels of A2AR immunoreactivity. These finding suggest that A2AR transcription may be induced in CD4+ iNKT cells as a result of NF-κB activation in SCD. In order to test this hypothesis further we examined cultured human iNKT cells. In cultured cells, blockade of NF-κB with Bay 11-7082 or IKK inhibitor VII prevented rapid induction of A2AR mRNA and protein upon iNKT activation. In conclusion, NF-κB-mediated induction of A2ARs in iNKT cells may serve as a counter-regulatory mechanism to limit the extent and duration of inflammatory immune responses. As activated iNKT cells express high levels of A2ARs following their activation, they may become highly sensitive to inhibition by A2AR agonists

Mechanostimulation-induced integrin αvβ6 and latency associated peptide coupling activates TGF-β and regulates cancer metastasis and stemness

The existence of cancer stem cells is the single most important factor contributing to cancer recurrence, and despite immense therapeutic relevance, little research has been done on investigating their origin. Through mechanotransduction, cells translate biophysical cues to biochemical signals. However, little is known about its role in acquisition of cancer stem cell characteristics in non-stem cells. Here, highly ordered nanoenvironments are engineered as models to induce mechanotransduction in cancer cells and elucidate how cell environment delivers precise physical cues via mechanotransduction to modulate expression and localization of key mesenchymal markers to induce epithelial-mesenchymal transition (EMT) and regulate cancer stemness. By initiating integrin αVβ6 and Latency associated peptide (LAP) interactions, cell nanoenvironment mechanically activates TGF-β canonical and non-canonical signaling pathways and induces Epithelial-Mesenchymal transition in U2OS osteosarcoma cells. As a consequence of TGF-β mechanical activation, a synchronous regulation in cancer stem-cell and pluripotency biomarkers is also observed which transcends to formation of cell organoids, a characteristic of cancer stem cells. Furthermore, nanoenvironment-derived cells promote tumor growth and metastasis in-vivo. Mechanistically, RNA-sequencing, RNA-interference and protein translocation experiments establish that cell nanoenvironment plays a decisive role in imparting stemness abilities to incoming cells via EMT and reveals how cells can exploit mechanical sensing to orchestrate tumorigenicity