All Posts Tagged With: "apoptosis"

Full article: http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1000499#top

Excerpt:

The protozoan parasite Theileria inhabits the host cell cytoplasm and possesses the unique capacity to transform the cells it infects, inducing continuous proliferation and protection against apoptosis. The transforming schizont is a multinucleated syncytium that resides free in the host cell cytoplasm and is strictly intracellular. To maintain transformation, it is crucial that this syncytium is divided over the two daughter cells at each host cell cytokinesis. This process was dissected using different cell cycle synchronization methods in combination with the targeted application of specific inhibitors. We found that Theileria schizonts associate with newly formed host cell microtubules that emanate from the spindle poles, positioning the parasite at the equatorial region of the mitotic cell where host cell chromosomes assemble during metaphase. During anaphase, the schizont interacts closely with host cell central spindle. As part of this process, the schizont recruits a host cell mitotic kinase, Polo-like kinase 1, and we established that parasite association with host cell central spindles requires Polo-like kinase 1 catalytic activity. Blocking the interaction between the schizont and astral as well as central spindle microtubules prevented parasite segregation between the daughter cells during cytokinesis. Our findings provide a striking example of how an intracellular eukaryotic pathogen that evolved ways to induce the uncontrolled proliferation of the cells it infects usurps the host cell mitotic machinery, including Polo-like kinase 1, one of the pivotal mitotic kinases, to ensure its own persistence and survival.

Full article: http://www.plosbiology.org/article/info:doi/10.1371/journal.pbio.1000499#top

Excerpt:

The protozoan parasite Theileria inhabits the host cell cytoplasm and possesses the unique capacity to transform the cells it infects, inducing continuous proliferation and protection against apoptosis. The transforming schizont is a multinucleated syncytium that resides free in the host cell cytoplasm and is strictly intracellular. To maintain transformation, it is crucial that this syncytium is divided over the two daughter cells at each host cell cytokinesis. This process was dissected using different cell cycle synchronization methods in combination with the targeted application of specific inhibitors. We found that Theileria schizonts associate with newly formed host cell microtubules that emanate from the spindle poles, positioning the parasite at the equatorial region of the mitotic cell where host cell chromosomes assemble during metaphase. During anaphase, the schizont interacts closely with host cell central spindle. As part of this process, the schizont recruits a host cell mitotic kinase, Polo-like kinase 1, and we established that parasite association with host cell central spindles requires Polo-like kinase 1 catalytic activity. Blocking the interaction between the schizont and astral as well as central spindle microtubules prevented parasite segregation between the daughter cells during cytokinesis. Our findings provide a striking example of how an intracellular eukaryotic pathogen that evolved ways to induce the uncontrolled proliferation of the cells it infects usurps the host cell mitotic machinery, including Polo-like kinase 1, one of the pivotal mitotic kinases, to ensure its own persistence and survival.

Full article: http://www.cancerdecisions.com/content/view/414/2/lang,english/

Excerpt:

A landmark paper on homeopathy and cancer has appeared in the February 2010 issue of the International Journal of Oncology. Scientists at the University of Texas M.D. Anderson Cancer Center (MDA), led by Moshe Frenkel, MD, have confirmed the ability of four homeopathic remedies to induce apoptosis (programmed cell death) in breast cancer cell lines in the laboratory. The scientists in question were from the Integrative Medicine Program, the Department of Molecular Pathology, and the Department of Melanoma Medical Oncology of MDA. Their two Indian collaborators were from the Banerji Homeopathic Research Foundation, Kolkata, India, where these same remedies are employed clinically with apparent success. The four ultra-dilute remedies in question were Carcinosin, Phytolacca, Conium and Thuja.

Inflammation has long been implicated as a contributor to pathogenesis
in many CNS illnesses, including Lyme neuroborreliosis. Borrelia
burgdorferi is the spirochete that causes Lyme disease and it is known
to potently induce the production of inflammatory mediators in a variety
of cells. In experiments where B. burgdorferi was co-cultured in vitro
with primary microglia, we observed robust expression and release of
IL-6 and IL-8, CCL2 (MCP-1), CCL3 (MIP-1?), CCL4 (MIP-1?) and CCL5
(RANTES), but we detected no induction of microglial apoptosis. In
contrast, SH-SY5Y (SY) neuroblastoma cells co-cultured with B.
burgdorferi expressed negligible amounts of inflammatory mediators and
also remained resistant to apoptosis. Continued