In the absence of a fully effective herpes simplex virus (HSV) vaccine, topical microbicides represent an important strategy for preventing HSV transmission. (؊)-Epigallocatechin gallate (EGCG) (molecular weight, 458.4) is the primary catechin in green tea. The present study shows that EGCG has greater anti-HSV activity than other green tea catechins and inactivates multiple clinical isolates of HSV type 1 (HSV-1) and HSV-2. EGCG reduced HSV-2 titers by >1,000-fold in 10 to 20 min and reduced HSV-1 titers by the same amount in 30 to 40 min. The anti-HSV activity of EGCG is due to a direct effect on the virion, and incubating Vero and CV1 cells with EGCG for 48 h prior to infection with HSV-1 and HSV-2, respectively, does not reduce HSV production. Electron microscopic (EM) studies showed that purified virions exposed to EGCG were damaged, and EM immunogold labeling of the envelope glycoproteins gB and gD was significantly reduced following EGCG treatment while capsid protein labeling was unchanged. When purified HSV-1 envelope glycoproteins gB and gD were incubated with EGCG and then examined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, lower-molecular-weight gB and gD bands decreased and new higher-molecular-weight bands appeared, indicating the EGCG-dependent production of macromolecular complexes. gB and gD are essential for HSV infectivity, and these results suggest that EGCG could inactivate HSV virions by binding to gB, gD, or another envelope glycoprotein. EGCG is stable in the pH range found in the vagina and appears to be a promising candidate for use in a microbicide to reduce HSV transmission.

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Estrogen stimulation promotes epithelial cell proliferation in estrogen receptor (ERα)-positive breast cancer. Many ERα target genes have been enumerated, but the identities of the key effectors mediating the estrogen signal remain obscure. During mouse mammary gland development, the EGF receptor ligand amphiregulin acts as an important stage-specific effector of estrogen signaling. In this study, we investigated the role of amphiregulin in breast cancer cell proliferation using human tissue samples and tumor xenografts in mice. Amphiregulin was enriched in ERα-positive human breast tumor cells and required for estrogen-dependent growth of MCF7 tumor xenografts. Further, amphiregulin levels were suppressed in patients treated with endocrine therapy. Suppression of EGF receptor signaling appeared necessary for the amphiregulin response in this setting. Our findings implicate amphiregulin as a critical mediator of the estrogen response in ERα-positive breast cancer, emphasizing the importance of EGF receptor signaling in breast tumor pathogenesis and therapeutic response.

Lay Abstract Autism is a complex developmental disability characterized by abnormalities in spoken language, socialization and repetitive behaviors. In recent years, an increase in the number of autism cases worldwide has been reported. Researchers have found evidence that autism is caused by multiple genetic factors, and a number of potential risk genes have been identified. Earlier we have found an increased frequency in subject with autism of a form of the enzyme glyoxalase I (Glo1) that has glutamic acid at position 111. By using lymphoblastoid and neuronal cells in culture, we now present evidence that this form of Glo1 is reduced in function, and consequently accumulates a toxic metabolite called methylglyoxal (MG). MG can form conjugates with cellular proteins, thereby compromising their function. We propose that an increase in conjugated proteins causes over-expression of receptors that bind these altered proteins, which in turn can initiate cascades of potentially harmful events. These studies suggest that in a subset of individuals with autism, the occurrence of the Glo1 polymorphism may precipitate changes in cellular structure and function that support risk for autism. Scientific Abstract Autism is a pervasive, heterogeneous, neurodevelopmental disability characterized by impairments in verbal communications, reciprocal social interactions, and restricted repetitive stereotyped behaviors. Evidence suggests the involvement of multiple genetic factors in the etiology of autism, and extensive genome-wide association studies have revealed several candidate genes that bear single nucleotide polymorphisms (SNPs) in non-coding and coding regions. We have shown that a non-conservative, non-synonymous SNP in the glyoxalase I gene, GLOI, may be an autism susceptibility factor. The GLOI rs2736654 SNP is a C→A change that causes an Ala111Glu change in the Glo1 enzyme. To identify the significance of the SNP, we have conducted functional assays for Glo1. We now present evidence that the presence of the A-allele at rs2736654 results in reduced enzyme activity. Glo1 activity is decreased in lymphoblastoid cells that are homozygous for the A allele. The Glu-isoform of Glo1 in these cells is hyperphosphorylated. Direct HPLC measurements of the glyoxalase I substrate, methylglyoxal (MG), show an increase in MG in these cells. Western blot analysis revealed elevated levels of the receptor for advanced glycation end products (RAGEs). We also show that MG is toxic to the developing neuronal cells. We suggest that accumulation of MG results in the formation of AGEs, which induce expression of the RAGE that during crucial neuronal development may be a factor in the pathology of autism.

We previously reported that the dismutase SOD1 is overexpressed in breast cancer. However, whether SOD1 plays an active role in tumor formation in vivo has never been demonstrated. Further, as luminal cells of normal breast epithelial cells are enriched in SOD1, whether SOD1 is essential for normal mammary gland development has never been determined. We initiated this study to investigate the role of SOD1 in mammary gland tumorigenesis as well as in normal mammary gland development. We crossed the inducible erbB2 (MMTV-iErbB2) and Wnt (MMTV-Wnt) transgenic mice to the SOD1 heterozygote or knockout mice. Our results show that SOD1 is essential for oncogene-driven proliferation, but not normal proliferation of the mammary gland associated with pregnancy or other normal proliferative tissues such as skin and intestines. We show that activation of the oncogene ErbB2 is associated with increased ROS and that high ROS sub-population of ErbB2 cancer cells show elevated SOD1. In the same cells, decrease in SOD1 is associated with an elevation in both apoptosis as well as oncogene-induced senescence. Based on these results, we suggest that SOD1 carries a housekeeping function that maintains ROS levels below a threshold that supports oncogene-dependent proliferation, while allowing escape from oncogene-induced senescence, independently of the oncogene driving tumor formation. These results identify SOD1 as an ideal target for cancer therapy as SOD1 inhibitors hold the potential to prevent the growth of cancers cells of diverse genotypes, activate multiple modes of cell death therefore making acquired resistance more difficult, while sparing normal tissues.