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Spinocerebellar ataxia type 7 (SCA7) is an autosomal dominant neurodegenerative disorder characterized by progressive cerebellar ataxia associated with retinal degeneration. The disease is rare in Japan, and this is the first full description of clinicopathological findings in a Japanese autopsy case of genetically confirmed SCA7 having 49 cytosine‐adenine‐guanine (CAG) trinucleotide repeats in the ataxin 7 gene. A 34‐year‐old Japanese man with no family history of clinically apparent neurodegenerative diseases presented with gait disturbance, gradually followed by truncal instability with progressive visual loss by the age of 42 years. He became wheelchair‐dependent by 51 years old, neurologically exhibiting cerebellar ataxia, slow eye movement, slurred and scanning speech, lower limb spasticity, hyperreflexia, action‐related slowly torsional dystonic movements in the trunk and limbs, diminished vibratory sensation in the lower limbs, auditory impairment, and macular degeneration. Brain magnetic resonance imaging revealed atrophy of the brainstem and cerebellum. He died of pneumonia at age 60 with a 26‐year clinical duration of disease. Postmortem neuropathological examination revealed pronounced atrophy of the spinal cord, brainstem, cerebellum, external globus pallidus (GP), and subthalamic nucleus, microscopically showing neuronal cell loss and fibrillary astrogliosis with polyglutamine‐immunoreactive neuronal nuclei and/or neuronal nuclear inclusions (NNIs). Degeneration was also accentuated in the oculomotor system, auditory and visual pathways, upper and lower motor neurons, and somatosensory system, including the spinal dorsal root ganglia. There was a weak negative correlation between the frequency of nuclear polyglutamine‐positive neurons and the extent of neuronal cell loss. Clinicopathological features in the present case suggest that neurological symptoms, such as oculomotor, auditory, visual, and sensory impairments, are attributable to degeneration in their respective projection systems affected by SCA7 pathomechanisms and that dystonic movement is related to more significant degeneration in the external than internal GP. [ABSTRACT FROM AUTHOR]

The contextual signals that regulate the expansion of prostate tumor progenitor cells are poorly defined. We found that a significant fraction of advanced human prostate cancers and castration-resistant metastases express high levels of the β4 integrin, which binds to laminin-5. Targeted deletion of the signaling domain of β4 inhibited prostate tumor growth and progression in response to loss of p53 and Rb function in a mouse model of prostate cancer (PB-TAg mice). Additionally, it suppressed Pten loss-driven prostate tumorigenesis in tissue recombination experiments. We traced this defect back to an inability of signaling-defective β4 to sustain self-renewal of putative cancer stem cells in vitro and proliferation of transit-amplifying cells in vivo. Mechanistic studies indicated that mutant β4 fails to promote transactivation of ErbB2 and c-Met in prostate tumor progenitor cells and human cancer cell lines. Pharmacological inhibition of ErbB2 and c-Met reduced the ability of prostate tumor progenitor cells to undergo self-renewal in vitro. Finally, we found that β4 is often coexpressed with c-Met and ErbB2 in human prostate cancers and that combined pharmacological inhibition of these receptor tyrosine kinases exerts antitumor activity in a mouse xenograft model. These findings indicate that the β4 integrin promotes prostate tumorigenesis by amplifying ErbB2 and c-Met signaling in tumor progenitor cells., Introduction Prostate cancer, the most common noncutaneous malignancy diagnosed in men, progresses from carcinoma in situ, termed prostatic intraepithelial neoplasia (PIN), to invasive and metastatic cancer, suggesting that multiple genetic [...]

In a series of experiments, the effects of soy protein isolate (SPI), defatted soy (DFS) or SPI supplemented with L-methionine (SPIM) were examined in the Long-Evans rat with a cinnamon coat color (LEC rat), a model animal of Wilson's disease with a hereditary defect in the Atp7b gene resulting in defective copper metabolism and copper accumulation in hepatocytes. Milk casein in the control AIN-93G diet (20 g/100 g) was totally or 60% replaced by the soy products, SPI, DFS or SPIM (L-Met added to be equal to that in the control diet) beginning when rats were 6 wk old. Copper and iron concentrations in SPI and DFS were measured and the concentrations of these metals in the salt mix were adjusted so that test and the control diets had the same final concentrations. Food intake did not differ among groups. Rats were euthanized when they became moribund with jaundice. Survival time in the SPI diet group was shorter (14.0 [+ or -] 0.8 wk) than in the control group (19.1 [+ or -] 1.7 wk) (P < 0.001), and that in the DFS diet group was intermediate (16.0 [+ or -] 1.7 wk). Survival time in the SPIM diet group did not differ from that of the SPI diet group. Copper concentrations in the livers of rats in the SPI and SPIM diet groups were ~80% higher than in rats fed the control diet. Liver iron concentrations did not differ among the groups. The results, including histological analyses, indicate that SPI enhances copper uptake into the liver cells and promotes liver cell damage in LEC rats. However, this did not occur in the livers of F344 rats with wild-type Atp7b. Recommendations to individuals suffering from Wilson's disease to avoid consuming soy protein may be warranted. KEY WORDS: * LEC rats * soy protein isolate * copper * Wilson's disease * liver cell damage

A monoclonal antibody, 7H6, was generated using a bile canaliculus-rich membrane fraction from rat liver as the antigenic substrate. 7H6 produced immunofluorescence patterns at the junctional complex regions of the hepatocytes and in rat intestine, patterns similar to those generated by antibodies to the junctional proteins ZO-1 and cingulin. However, immunoblot analysis showed that the antigen recognized by 7H6 was distinct from these proteins. The nature and function of this antigenic protein is yet to be elucidated.