On how CCN6 suppresses breast cancer growth and invasion

Living cells communicate with their microenvironment and exchange information through signaling pathways in order to carry out most biological processes. The CCN family of proteins has the ability to coordinate the extracellular and intracellular signaling pathways and epithelial-stromal cross-talks. CCN proteins have been shown to play roles in multiple processes including cancer, either as tumor suppressors or oncogenes. Particularly, loss of CCN6 expression has been reported in highly aggressive breast cancer types, especially in inflammatory breast cancer and breast cancer with axillary lymph node metastasis. Recent findings can better explain the biological relevance of CCN6 as a tumor suppressor protein in breast tumorigenesis. CCN6 loss triggers the process of epithelial to mesenchymal transition (EMT), which converts epithelial cells into migratory and invasive mesenchymal-like cells at least in part through modulation of IGF-1 receptor signaling pathway. Emerging data support the hypothesis that CCN6 also exerts growth factor independent functions, especially related to cell survival and anoikis resistance. Thus, our work provides new insights into the functions and mechanisms of tumor suppression exerted by CCN6 in the breast.     

Hydrogen peroxide-induced apoptosis-like cell death in Entamoeba histolytica

The microaerophilic intestinal parasitic protozoan Entamoeba histolytica has been previously shown to be highly susceptible to oxidative stress induced by hydrogen peroxide. However the mechanism of cell death was not investigated. Studies presented in this paper demonstrate several morphological features in the parasite when exposed to H₂O₂ which are identical to metazoan apoptotic phenotype indicating a possible apoptosis-like cell death exhibited by E. histolytica in response to H₂O₂ treatment. Trophozoite cell shrinkage, DNA fragmentation, phosphatidyl serine externalization and increased endogenous reactive oxygen species level have been observed in the protozoan parasite when exposed to 2.0 mM H₂O₂ for different time periods. Although the parasite genome is completely devoid of any of the homologues of mammalian caspases it still codes for a huge number of cysteine proteases which may take over the apoptotic function of the caspases. But the present study indicates the existence of a cysteine protease independent programmed cell death in the parasite since E-64 the specific cysteine protease inhibitor could not rescue the cells from H₂O₂ induced apoptosis-like cell death.     

Technology and research developments in carotid image registration

Brain stroke is the leading cause of death worldwide. Mortality, morbidity and economic effects of stroke are alarming. Carotid atherosclerosis is the most common cause of stroke. Early identification, monitoring and quantification of carotid plaque with the help of imaging modalities can help manage the stroke and evaluate the effectiveness of medical therapy. Carotid image registration has the potential to improve the monitoring, quantification and characterization of the disease. It helps to accurately correlate the findings of various imaging modalities for the diagnostic and therapeutic purposes. This paper aims to present the current state-of-the-art in carotid image registration techniques. For the monomodality registration, ultrasound and magnetic resonance imaging are the primary concerns. Multimodality registration will cover the combination of different modalities. The registration process and validation methods for carotid image registration are also discussed.     

No evidence of murine leukemia virus-related viruses in live attenuated human vaccines

Background

The association of xenotropic murine leukemia virus (MLV)-related virus (XMRV) in prostate cancer and chronic fatigue syndrome reported in previous studies remains controversial as these results have been questioned by recent data. Nonetheless, concerns have been raised regarding contamination of human vaccines as a possible source of introduction of XMRV and MLV into human populations. To address this possibility, we tested eight live attenuated human vaccines using generic PCR for XMRV and MLV sequences. Viral metagenomics using deep sequencing was also done to identify the possibility of other adventitious agents.

Results

All eight live attenuated vaccines, including Japanese encephalitis virus (JEV) (SA-14-14-2), varicella (Varivax), measles, mumps, and rubella (MMR-II), measles (Attenuvax), rubella (Meruvax-II), rotavirus (Rotateq and Rotarix), and yellow fever virus were negative for XMRV and highly related MLV sequences. However, residual hamster DNA, but not RNA, containing novel endogenous gammaretrovirus sequences was detected in the JEV vaccine using PCR. Metagenomics analysis did not detect any adventitious viral sequences of public health concern. Intracisternal A particle sequences closest to those present in Syrian hamsters and not mice were also detected in the JEV SA-14-14-2 vaccine. Combined, these results are consistent with the production of the JEV vaccine in Syrian hamster cells.

Conclusions

We found no evidence of XMRV and MLV in eight live attenuated human vaccines further supporting the safety of these vaccines. Our findings suggest that vaccines are an unlikely source of XMRV and MLV exposure in humans and are consistent with the mounting evidence on the absence of these viruses in humans.     

Preclinical evaluation of DO3P-AME-DO3P: a polyazamacrocyclic methylene phosphonate for diagnosis and therapy of skeletal metastases

A phosphonate derivative 10'-bis(acetamido)-ethane-bis[1,4,7-tri(methylene phosphonic acid)-1,4,7,10-tetraazacyclododecane] (DO3P-AME-DO3P), was synthesized with 90% yield in high purity. It was labeled with (99m)Tc in 97.5% efficiency and specific activity of 112-250 MBq/μmol. The binding affinity of (99m)Tc-DO3P-AME-DO3P towards bone minerals was tested in vitro by using hydroxy apatite as a bone model with absorption of 93% during the first hour of the experiment. Receptor binding assay on human bone cell line SAOS-2 demonstrated K(d) value of 1.07 nM. Cell binding studies of DO3P-AME-DO3P on osteoblasts and osteoclasts cells performed in vitro displayed preferential affinity of the compound towards osteoclast (167.95 ± 3.56% dose/mg protein). The serum stability of (99m)Tc complex was found to be 96.8% after 24 h. Blood kinetics of (99m)Tc-DO3P-AME-DO3P performed on normal rabbits showed fast clearance with t(1/2)(F) = 15 min ± 0.014 min and t(1/2)(S) = 4 h 3 min ± 0.09 min. Biodistribution studies carried out in normal BALB/c mice showed bone-to-blood ratio of 20 and bone-to-muscle ratio of 33. The bone tissue demonstrated highest concentration of bound radioactivity with 10.73% ID/g at 1 h post injection. The protonation and stability constants were determined by pH-potentiometry titrations. The stability constants of DO3P-AME-DO3P with Lu(III), Sm(III), and Ho(III) were 19.7, 21.8, and 20.2 determined by "out of cell" method. The excellent bone seeking properties of DO3P-AME-DO3P make it a candidate of choice for SPECT imaging and preferential uptake of the compound in osteoclasts in comparison to osteoblasts; BMM and BMC can be used to understand the pathway of pathogenesis of osteoporosis and skeletal metastases.     

Studies on Exo-Chitinase Production from Trichoderma asperellum UTP-16 and Its Characterization

The growth conditions for chitinase production by Trichoderma asperellum UTP-16 in solid state fermentation was optimized using response surface methodology based on central composite design. The chitinase production was optimized, using one-factor at a time approach, with six independent variables (temperature, pH, NaCl, incubation period, nitrogen and carbon sources) and 3.31 Units per gram dry substrate (U gds⁻¹) exo-chitinase yield was obtained. A 21.15% increase was recorded in chitinase activity (4.01 U gds⁻¹) through surface response methodology, indicates that it is a powerful and rapid tool for optimization of physical and nutritional variables. Further, efficiency of crude enzyme was evaluated against phytopathogenic Fusarium spp. and a mycelial growth inhibition up to 3.5–6.5 mm was achieved in well diffusion assay. These results could be supplemented as basic information for the development of enzyme based formulation of T. asperellum UTP-16 and its use as a biocontrol agent.     

Three Dimensional Cultures: A Tool To Study Normal Acinar Architecture vs. Malignant Transformation Of Breast Cells

Invasive breast carcinomas are a group of malignant epithelial tumors characterized by the invasion of adjacent tissues and propensity to metastasize. The interplay of signals between cancer cells and their microenvironment exerts a powerful influence on breast cancer growth and biological behavior¹. However, most of these signals from the extracellular matrix are lost or their relevance is understudied when cells are grown in two dimensional culture (2D) as a monolayer. In recent years, three dimensional (3D) culture on a reconstituted basement membrane has emerged as a method of choice to recapitulate the tissue architecture of benign and malignant breast cells. Cells grown in 3D retain the important cues from the extracellular matrix and provide a physiologically relevant ex vivo system^2,3. Of note, there is growing evidence suggesting that cells behave differently when grown in 3D as compared to 2D⁴. 3D culture can be effectively used as a means to differentiate the malignant phenotype from the benign breast phenotype and for underpinning the cellular and molecular signaling involved³. One of the distinguishing characteristics of benign epithelial cells is that they are polarized so that the apical cytoplasm is towards the lumen and the basal cytoplasm rests on the basement membrane. This apico-basal polarity is lost in invasive breast carcinomas, which are characterized by cellular disorganization and formation of anastomosing and branching tubules that haphazardly infiltrates the surrounding stroma. These histopathological differences between benign gland and invasive carcinoma can be reproduced in 3D^6,7. Using the appropriate read-outs like the quantitation of single round acinar structures, or differential expression of validated molecular markers for cell proliferation, polarity and apoptosis in combination with other molecular and cell biology techniques, 3D culture can provide an important tool to better understand the cellular changes during malignant transformation and for delineating the responsible signaling.