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Incretin therapies have received much attention because of their tissue-protective effects, which extend beyond those associated with glycemic control. Cancer is a primary cause of death in patients who have diabetes mellitus. We previously reported antiprostate cancer effects of the glucagonlike peptide-1 (GLP-1) receptor (GLP-1R) agonist exendin-4 (Ex-4). Breast cancer is one of the most common cancers in female patients who have type 2 diabetes mellitus and obesity. Thus, we examined whether GLP-1 action could attenuate breast cancer. GLP-1R was expressed in human breast cancer tissue and MCF-7, MDA-MB-231, and KPL-1 cell lines. We found that 0.1 to 10 nM Ex-4 significantly decreased the number of breast cancer cells in a dose-dependent manner. Although Ex-4 did not induce apoptosis, it attenuated breast cancer cell proliferation significantly and dose-dependently. However, the dipeptidyl peptidase-4 inhibitor linagliptin did not affect breast cancer cell proliferation. When MCF-7 cells were transplanted into athymic mice, Ex-4 decreased MCF-7 tumor size in vivo. Ki67 immunohistochemistry revealed that breast cancer cell proliferation was significantly reduced in tumors extracted from Ex-4-treated mice. In MCF-7 cells, Ex-4 significantly inhibited nuclear factor κB (NF-κB ) nuclear translocation and target gene expression. Furthermore, Ex-4 decreased both Akt and IκB phosphorylation. These results suggest that GLP-1 could attenuate breast cancer cell proliferation via activation of GLP-1R and subsequent inhibition of NF-κB activation.

Recently, pleiotropic benefits of incretin therapy beyond glycemic control have been reported. Although cancer is one of the main causes of death in diabetic patients, few reports describe the anticancer effects of incretin. Here, we examined the effect of the incretin drug exendin (Ex)-4, a GLP-1 receptor (GLP-1R) agonist, on prostate cancer. In human prostate cancer tissue obtained from patients after they had undergone radical prostatectomy, GLP-1R expression colocalized with P504S, a marker of prostate cancer. In in vitro experiments, Ex-4 significantly decreased the proliferation of the prostate cancer cell lines LNCap, PC3, and DU145, but not that of ALVA-41. This antiproliferative effect depended on GLP-1R expression. In accordance with the abundant expression of GLP-1R in LNCap cells, a GLP-1R antagonist or GLP-1R knockdown with small interfering RNA abolished the inhibitory effect of Ex-4 on cell proliferation. Although Ex-4 had no effect on either androgen receptor activation or apoptosis, it decreased extracellular signal–regulated kinase (ERK)-mitogen-activated protein kinase (MAPK) phosphorylation in LNCap cells. Importantly, Ex-4 attenuated in vivo prostate cancer growth induced by transplantation of LNCap cells into athymic mice and significantly reduced the tumor expression of P504S, Ki67, and phosphorylated ERK-MAPK. These data suggest that Ex-4 attenuates prostate cancer growth through the inhibition of ERK-MAPK activation.

The presence of the so-called Hodgkin and Reed-Sternberg (H-RS) like cells may occur in T-cell non-Hodgkin lymphoma. Reported herein is the autopsy case of Hodgkin-like peripheral T-cell lymphoma (PTCL) in a 77-year-old male with gradual submandibular lymph node enlargement. The first biopsy showed Hodgkin-like PTCL, initially misdiagnosed as classical Hodgkin lymphoma. Although he was treated with a regimen of ABVD, his disease recurred with cervical lymph node enlargement. A second biopsy showed angioimmunoblastic T-cell lymphoma (AITL) and H-RS like cells became obscure. Despite treatment with the CHOP regimen, he died. An autopsy confirmed that only Hodgkin-like lesions preserved while the AITL component had disappeared. This clinical course is very interesting in that only the Hodgkin-like lesions were systematically exacerbated and became the main cause of death. There are no reports of Hodgkin-like PTCL following AITL and finally preserved Hodgkin-like lesions in autopsy.

Serum profiles of lipids and/or liver enzymes are established markers for the estimation of insulin resistance and diabetic risk in the non-diabetic middle-aged population. To identify prediabetic markers in young subjects, 110 young male subjects (20-29 years of age) with normal glucose tolerance (NGT) were divided into two groups by median body mass index (BMI),22.18 (n=55) and ≥22.18 (n=55) kg/m(2). Indices of insulin sensitivity including HOMA-IR and ISI composite, indices of β-cell function including HOMA-β, insulinogenic index (ΔI(30)/ΔG(30)) and ΔI(30)/ΔG(30)/ HOMA-IR were calculated. Statistical associations between these parameters and the serum lipid profiles and liver function were evaluated. Alanine aminotransferase (ALT), γ-glutamyltransferase (GGT), total cholesterol (TC) and triglyceride (TG) levels were inversely correlated with the ISI composite among individuals with BMI ≥22.18 kg/m(2) but not those with BMI22.18 kg/m(2). Multivariate regression analysis revealed that, in Group N, the plasma glucose levels at 60 min (PG(60)) were inversely correlated with the ISI composite and the insulinogenic index, and were positively correlated with the GGT, TC and TG levels. On the other hand, in Group L, PG(60) was correlated with the insulinogenic index, TC and TG levels. In conclusion, elevated levels of GGT, TC and TG are good clinical markers to predict diabetic risks, even in young NGT males. Of these, GGT was the most strongly related factor among subjects with relatively high BMI.

A polymerase chain reaction (PCR) based procedure was modified to determine the deletion of mitochondrial DNA (mtDNA). The protocol consists of coamplification both of deleted and wild-type segments of mtDNA using a long PCR technique; evaluation of the deleted portion within the amplified DNA segments by restriction enzyme digestion followed by densitometrical analysis; and direct subcloning into a plasmid vector for DNA sequencing. The procedure revealed a 5.3 kb deletion of mtDNA in the biopsied muscle tissue obtained from a patient clinically diagnosed with progressive external ophthalmoplegia. The 5′ and 3′ sequences at both sides of the breakpoint comprise a 17 bp palindrome and 5 bp tandem repeats, suggesting that the deletion might occur through slipped mispairing and other novel mechanisms. This improved procedure has the potential to detect deletions occurring in the entire length of mtDNA, and mighty be useful for clinical screening of progressive external ophthalmoplegia.

Different protocols are described for the combined staining method by which argyrophilic nucleolar organizer region sites can be evaluated in human astrocytes that are immunoreactive for glial fibrillary acidic protein. Among the four protocols studied, the following method was superior to others in terms of unambiguous visualization of the regions in glial fibrillary acidic protein-positive astrocytes; the first step was immunostaining for the protein with a blue colour reaction of alkaline phosphatase, followed by sequential colloidal silver staining for the regions. By this double staining method, we have demonstrated that the reactive astrocytes found in white matter around the metastatic lesion of carcinoma and the infarction, contain more argyrophilic nucleolar organizer regions in terms of the count as well as the area than glial fibrillary acidic protein-positive astrocytes present in the white matter of the normal brain. In conclusion, the double staining may provide valuable information on the cellular activity of astroglia when performed on routine formalin-fixed paraffin sections of the human brain.