Down-regulation of LATS1 and LATS2 mRNA expression by promoter hypermethylation and its association with biologically aggressive phenotype in human breast cancers.

PURPOSE: LATS1 and LATS2 are tumor suppressor genes implicated in the regulation of cell cycle. Methylation status of the promoter regions of these genes as well as its correlation with their mRNA levels were studied in human breast cancers. Correlation of LATS1 and LATS2 mRNA levels with clinicopathologic characteristics of breast tumors were also studied. EXPERIMENTAL DESIGN: Methylation status of promoter regions of LATS1 and LATS2 was studied by a methylation-specific PCR and mRNA expression levels of LATS1 and LATS2 were determined by a real-time PCR assay in 30 breast cancers. In addition, correlation of LATS1 and LATS2 mRNA levels with clinicopathologic characteristics was studied in 117 breast cancers. RESULTS: Methylation-specific PCR showed that of 30 tumors, LATS1 promoter region was hypermethylated in 17 tumors (56.7%) and LATS2 promoter region was hypermethylated in 15 (50.0%) tumors. LATS1 mRNA levels in breast tumors with hypermethylation (2.15 +/- 0.37, mean +/- SE) were significantly (P < 0.01) lower than those without hypermethylation (6.09 +/- 1.38), and LATS2 mRNA levels in breast tumors with hypermethylation (1.42 +/- 0.66) were also significantly (P < 0.01) lower than those without hypermethylation (3.10 +/- 1.00). The decreased expression of LATS1 or LATS2 mRNA was significantly associated with a large tumor size, high lymph node metastasis, and estrogen receptor and progesterone receptor negativity. Furthermore, the decreased expression of LATS1 mRNA, but not LATS2 mRNA, was significantly (P < 0.05) associated with a poor prognosis. CONCLUSIONS: Hypermethylation of the promoter regions of LATS1 and LATS2 likely plays an important role in the down-regulation of their mRNA levels in breast cancers, and breast cancers with a decreased expression of LATS1 or LATS2 mRNA levels have a biologically aggressive phenotype.     

Therapeutic advances in BIG3‐PHB2 inhibition targeting the crosstalk between estrogen and growth factors in breast cancer

Our previous studies demonstrated that specific inhibition of the BIG3‐PHB2 complex, which is a critical modulator in estrogen (E2) signaling, using ERAP, a dominant negative peptide inhibitor, leads to suppression of E2‐dependent estrogen receptor (ER) alpha activation through the reactivation of the tumor suppressive activity of PHB2. Here, we report that ERAP has significant suppressive effects against synergistic activation caused by the crosstalk between E2 and growth factors associated with intrinsic or acquired resistance to anti‐estrogen tamoxifen in breast cancer cells. Intrinsic PHB2 released from BIG3 by ERAP effectively disrupted each interaction of membrane‐associated ERα and insulin‐like growth factor 1 receptor beta (IGF‐1Rβ), EGFR, PI3K or human epidermal growth factor 2 (HER2) in the presence of E2 and the growth factors IGF or EGF, followed by inhibited the activation of IGF‐1Rβ, EGFR or HER2, and reduced Akt, MAPK and ERα phosphorylation levels, resulting in significant suppression of proliferation of ERα‐positive breast cancer cells in vitro and in vivo. More importantly, combined treatment with ERAP and tamoxifen led to a synergistic suppression of signaling that was activated by crosstalk between E2 and growth factors or HER2 amplification. Taken together, our findings suggest that the specific inhibition of BIG3‐PHB2 is a novel potential therapeutic approach for the treatment of tamoxifen‐resistant breast cancers activated by the crosstalk between E2 and growth factor signaling, especially in premenopausal women.     

A device for adsorbing unbound, unconjugated bilirubin and its effects in vitro and in a hyperbilirubinemic newborn piglet

AIMS: A novel blood purification material that we previously reported as a superantigen- and cytokine-adsorbing device (SCAD) was evaluated for its ability to adsorb unbound, unconjugated bilirubin (UUBil) in vitro and in vivo. METHODS: In albumin-containing buffer, UUBil was dissolved and circulated through the SCAD column. Also, bilirubin was infused into low-body weight newborn piglets and hemoperfused for 3 h over SCAD columns. RESULTS: In albumin-containing buffer, concentration of bilirubin decreased from 34 to 0.6 mg/dL within 5 h and the SCAD fiber turned brown, indicating that bilirubin was adsorbed onto the surface of the adsorbent and was not degraded during the circulation. Using the hyperbilirubinemia swine, clearances of total bilirubin (TBil), direct bilirubin (DBil), and indirect bilirubin (IdBil) were significantly higher (P<0.01) in the SCAD group compared with the control group. The clearances of TBil, DBil, and IdBil at 3 h after the initiation of the bilirubin infusion were 0.47, 0.53, and 0.45 mL/min, respectively, at a blood flow rate of 2.5 mL/min, and this result indicates that almost 20% of bilirubins were adsorbed to the SCAD column in a single passage. CONCLUSION: These results provide initial evidence that SCAD treatment is effective in the removal of UUBil and can be performed safely in newborn animals.     

Blue rubber bleb nevus syndrome: Report of a patient with hemangiomas of the vaginal portion of the cervix appearing during pregnancy

Blue rubber bleb nevus syndrome (BRBNS) is a rare disorder showing venous malformations in the skin and gastrointestinal tract, and other internal organs. We encountered a patient with BRBNS in whom hemangiomas of the uterine cervix appeared during pregnancy. This was apparently the first reported occurrence. To avoid unexpected bleeding from hemangiomas, patients with BRBNS should be examined repeatedly for hemangiomas of the birth canal, and special care should be taken in deciding the mode of delivery.     

Direct visualization of glucagon‐like peptide‐1 secretion by fluorescent fusion proteins

Live‐cell imaging with fluorescent proteins (FPs) is a powerful tool for investigating the exocytosis processes of hormones. However, the secretion process of glucagon‐like peptide‐1 (GLP‐1) has not been visualized by FPs, which might be because tagging FPs inhibits GLP‐1 synthesis through the post‐translational processing from proglucagon. Here, we have developed FP‐tagged GLP‐1 by inserting FPs into the middle of GLP‐1 and adding the proglucagon signal peptide. Confocal imaging confirmed that GLP‐1 fused to FPs with high folding efficiency showed granular structure, in which secretory vesicle markers colocalized. The fluorescence intensity of FP in the culture supernatant from cells treated with KCl or forskolin was significantly increased compared with those from untreated cells. Furthermore, FP‐tagged GLP‐1 enables direct visualization of stimulation‐dependent exocytosis of GLP‐1 at a single granule resolution with total internal reflection fluorescence microscopy. FP‐tagged GLP‐1 might facilitate the screening of GLP‐1 secretagogues and the discovery of new antidiabetic drugs.     

Application of laparoscopic distal pancreatectomy for normal anatomy after hiatal hernia repair: A case report

We describe a case of pancreatic tumor associated with a giant type IV hiatal hernia that had prolapsed into the posterior mediastinum. Hiatal hernia repair should be performed first because it enables laparoscopic distal pancreatectomy to be performed in the normal anatomical position.     

Pemphigus with thymoma improved by thymectomy: report of a case

A 53-year-old female with pemphigus vulgaris received treatment with prednisolone for 3 years. On chest computed tomography performed at follow-up, an anterior–mediastinal tumor (4 cm × 3 cm) was detected and diagnosed as a thymoma. Although amyosthenia was absent, the patient’s anti-acetylcholine-receptor antibody level was high, and she was positive for anti-desmoglein 3 antibodies. She underwent extended thymectomy in the same year, following which both the anti-acetylcholine receptor antibody and the anti-desmoglein 3 antibody levels were normalized. The patient’s skin symptoms improved, and the steroid dose was gradually lowered and finally discontinued 4 years postoperatively. Extended thymectomy may be an effective therapy for treating patients with pemphigus.     

Tissue‐specific expression and silencing phenotypes of mitochondrial phosphate carrier paralogues in several insect species

The mitochondrial phosphate carrier gene (PiC) encodes a membrane protein that mediates the supply of inorganic phosphate from the cytosol into the mitochondrial matrix. This substrate‐specific transport system plays an important role in efficient ATP synthesis. Mammals appear to have only one PiC with two alternative splicing variants whose functional differences remain unclear. The present study is the first to characterize the multiple genes that encode PiC in insects. Bombyx mori was found to have two PiC paralogues, one ubiquitous and one testis‐specific, the latter seeming to be present only in Lepidoptera. Drosophila melanogaster was found to harbour two PiC paralogues, whereas Liriomyza chinensis, another dipteran, has three PiC paralogues. Two PiCs were found to be present in Plautia stali, and silencing either of these genes affected the normal development of P. stali nymphs, although their expression patterns differed amongst tissues. Schistocerca gregaria and Locusta migratoria have two PiC each, with different expression patterns. Tribolium castaneum was found to have only one PiC, which appears to play an essential role in larval development. Thus, although the inorganic phosphate transport system appears to be conserved across eukaryotes, PiC has become specialized in the different tissues of different insect species.