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Green tea epigallocatechin gallate (EGCG) and microRNA (miRNA) molecules modulate obesity. Nevertheless, it is still unknown whether EGCG modulates fat cell growth via miRNA-related signaling. In this study, white preadipocytes were used to examine whether the antimitogenic effect of EGCG on fat cells is regulated by the miR-143/MAPK7 pathway. We showed that EGCG upregulated the levels of miR-143, but not miR-155, in 3T3-L1 preadipocytes. Moreover, EGCG downregulated MAPK7 mRNA and protein levels time- and dose-dependently. MAPK7 expression increased during 3T3-L1 cell proliferation. miR-143 overexpression in the absence of EGCG mimicked the effects of EGCG to suppress preadipocyte growth and MAPK7 expression, whereas knockdown of miR-143 antagonized the EGCG-altered levels of miR-143, MAPK7, and pERK1/2 and reversed the EGCG-inhibited cell growth. These findings suggest that EGCG inhibits 3T3-L1 cell growth via miR-143/MAPK7 pathway.

Prostate cancer (PCa) is a reproductive system cancer in elderly men. We investigated the effects of betel nut arecoline on the growth of normal and cancerous prostate cells. Normal RWPE-1 prostate epithelial cells, androgen-independent PC-3 PCa cells, and androgen-dependent LNCaP PCa cells were used. Arecoline inhibited their growth in dose- and time-dependent manners. Arecoline caused RWPE-1 and PC-3 cell cycle arrest in the G2/M phase and LNCaP cell arrest in the G0/G1 phase. In RWPE-1 cells, arecoline increased the expression of cyclin-dependent kinase (CDK)-1, p21, and cyclins B1 and D3, decreased the expression of CDK2, and had no effects on CDK4 and cyclin D1 expression. In PC-3 cells, arecoline decreased CDK1, CDK2, CDK4, p21, p27, and cyclin D1 and D3 protein expression and increased cyclin B1 protein expression. In LNCaP cells, arecoline decreased CDK2, CDK4, and cyclin D1 expression, increased p21, p27, and cyclin D3 expression, had no effects on CDK1 and cyclin B1 expression. The antioxidant N-acetylcysteine blocked the arecoline-induced increase in reactive oxygen species production, decreased cell viability, altered the cell cycle, and changed the cell cycle regulatory protein levels. Thus, arecoline oxidant exerts differential effects on the cell cycle through modulations of regulatory proteins.

Endothelin (ET)-1 regulates adipogenesis and the endocrine activity of fat cells. However, relatively little is known about the ET-1 signaling pathway in preadipocyte growth. We used 3T3-L1 preadipocytes to investigate the signaling pathways involved in ET-1 modulation of preadipocyte proliferation. As indicated by an increased number of cells and greater incorporation of bromodeoxyuridine (BrdU), the stimulation of preadipocyte growth by ET-1 depends on concentration and timing. The concentration of ET-1 that increased preadipocyte number by 51–67% was ~100 nM for ~24–48 h of treatment. ET-1 signaling time dependently stimulated phosphorylation of ERK, c-JUN, STAT3, AMPK, and PKCα/βII proteins but not AKT, JNK, or p38 MAPK. Treatment with an ETAR antagonist, such as BQ610, but not ETBR antagonist BQ788, blocked the ET-1-induced increase in cell proliferation and phosphorylated levels of ERK, c-JUN, STAT3, AMPK, and PKCα/βII proteins. In addition, pretreatment with specific inhibitors of ERK1/2 (U0126), JNK (SP600125), JAK2/STAT3 (AG490), AMPK (compound C), or PKC (Ro318220) prevented the ET-1-induced increase in cell proliferation and reduced the ET-1-stimulated phosphorylation of ERK1/2, c-JUN, STAT3, AMPK, and PKCα/β. Moreover, the SphK antagonist suppressed ET-1-induced cell proliferation and ERK, c-JUN, STAT3, AMPK, and PKC phosphorylation, and the SMase2 antagonist suppressed ET-1-induced cell proliferation. However, neither the p38 MAPK antagonist nor the CerS inhibitor altered the effect of ET-1. The results indicate that ETAR, JAK2/STAT3, ERK1/2, JNK/c-JUN, AMPK, PKC, SphK, and SMase2, but not ETBR, p38 MAPK, or CerS, are necessary for the ET-1 stimulation of preadipocyte proliferation.

The present study was designed to investigate the pathways involved in the effect of betel nut arecoline on cell viability in 3T3-L1 preadipocytes. Arecoline, but not arecaidine or guvacine, inhibited preadipocyte viability in a concentration- and time-dependent manner. Arecoline arrested preadipocyte growth in the G2/M phase of the cell cycle; decreased the total levels of cyclin-dependent kinase 1 (CDK1), p21, and p27 proteins; increased p53 and cyclin B1 protein levels; and had no effect on CDK2 protein levels. These results suggested that arecoline selectively affected a particular CDK subfamily. Arecoline inhibited AMP-activated protein kinase (AMPK) activity; conversely, the AMPK activator, AICAR, blocked the arecoline-induced inhibition of cell viability. Pre-treatment with the antioxidant, N-acetylcysteine, prevented the actions of arecoline on cell viability, G2/M growth arrest, reactive oxygen species (ROS) production, and the levels of CDK1, p21, p27, p53, cyclin B1, and phospho-AMPK proteins. These AMPK- and ROS-dependent effects of arecoline on preadipocyte growth may be related to the mechanism underlying the modulatory effect of arecoline on body weight.

This study investigated the pathways involved in EGCG modulation of insulin-like growth factor (IGF)-stimulated glucose uptake in 3T3-L1 adipocytes. EGCG inhibited IGF-I and IGF-II stimulation of adipocyte glucose uptake with dose and time dependencies. EGCG at 20μM for 2h decreased IGF-I- and IGF-II-stimulated glucose uptake by 59% and 64%, respectively. Pretreatment of adipocytes with antibody against the EGCG receptor (also known as the 67-kDa laminin receptor; 67LR), prevented the effects of EGCG on IGF-increased glucose uptake, but pretreatment with normal rabbit immunoglobulin did not. This suggests that the 67LR mediates the anti-IGF effect of EGCG on adipocyte glucose uptake. Further analysis indicated EGCG, IGF-I, and IGF-II did not alter total levels of GLUT1 or GLUT4 protein. However, EGCG prevented the IGF-increased GLUT4 levels in the plasma membrane and blocked the IGF-decreased GLUT4 levels in low-density microsomes. Neither EGCG nor its combination with IGF altered GLUT1 protein levels in the plasma membrane and low-density microsomes. EGCG also suppressed the IGF-stimulated phosphorylation of IGF signaling molecules, PKCζ/λ, but not AKT and ERK1/2, proteins. This study suggests that EGCG suppresses IGF stimulation of 3T3-L1 adipocyte glucose uptake through inhibition of the GLUT4 translocation, but not through alterations of the GLUT1 pathway.

Resistin and endothelin (ET)-1 have been reported to inhibit adipogenesis and regulate adipocyte insulin resistance, respectively. Although both hormones interact with each other, the exact signaling pathway of ET-1 to act on resistin gene expression is still unknown. Using 3T3-L1 adipocytes, we investigated the signaling pathways involved in ET-1-stimulated resistin gene expression. The up-regulation of resistin mRNA expression by ET-1 depends on concentration and timing. The concentration of ET-1 that increased resistin mRNA levels by 100%-250% was approximately 100 nM for a range of 0.25-12 hours of treatment. Treatment with actinomycin D blocked ET-1-increased resistin mRNA levels, suggesting that the effect of ET-1 requires new mRNA synthesis. Treatment with an inhibitor of the ET type-A receptor, such as N-[1-Formyl-N-[N-[(hexahydro-1H-azepin-1-yl)carbonyl]-L-leucyl]-D-tryptophyl]-D-tryptophan (BQ610), but not with the ET type-B receptor antagonist N-[(cis-2,6-Dimethyl-1-piperidinyl)carbonyl]-4-methyl-L-leucyl-1-(methoxycarbonyl)-D-tryptophyl-D-norleucine (BQ788), blocked ET-1, increased the levels of resistin mRNA, and phosphorylated levels of downstream signaling molecules, such as ERK1/2, c-Jun N-terminal kinases (JNKs), protein kinase B (AKT), and signal transducer and activator of transcription 3 (STAT3). Moreover, pretreatment of specific inhibitors of either ERK1/2 (1,4-diamino-2,3-dicyano-1,4-bis[2-aminophenylthio]butadiene [U0126] and 2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one [PD98059], two inhibitors of MEK1), JNKs (SP600125), phosphatidylinositol 3-kinase/AKT (LY294002 and Wortmannin), or Janus kinase 2 (JAK2)/STAT3 ((E)-2-Cyano-3-(3,4-dihydrophenyl)-N-(phenylmethyl)-2-propenamide, AG490) prevented ET-1-increased levels of resistin mRNA and reduced the ET-1-stimulated phosphorylation of ERK1/2, JNKs, AKT, and STAT3, respectively. However, the p38 kinase antagonist 4-[5-(4-Fluorophenyl)-2-[4-(methylsulfonyl)phenyl]-1H-imidazol-4-yl]pyridine (SB203580) did not alter the effect of ET-1. These results imply that ET type-A receptor, ERK1/2, JNKs, AKT, and JAK2, but not ET type-B receptor or p38, are necessary for the ET-1 stimulation of resistin gene expression. In vivo observations that ET-1 increased resistin mRNA and protein levels in sc and epididymal adipose tissues support the in vitro findings.

Endothelin (ET)-1 and suppressor of cytokine signaling (SOCS)-3 were respectively found to regulate energy metabolism and hormone signaling in fat cells. Although ET-1 can also regulate the expression of SOCS-3-stimulating hormones, it is still unknown whether ET-1 regulates SOCS-3 gene expression. This study investigated the pathways involved in ET-1's modulation of SOCS-3 gene expression in 3T3-L1 adipocytes. ET-1 upregulated SOCS-3 mRNA and protein expression in dose- and time-dependent manners. The concentration of ET-1 that increased SOCS-3 mRNA levels by 250-400% was ∼100nM with 2-4h of treatment. Treatment with actinomycin D prevented ET-1-stimulated SOCS-3 mRNA expression, suggesting that the effect of ET-1 requires new mRNA synthesis. Pretreatment with the ET type A receptor (ET(A)R) antagonist, BQ-610, but not the ET type B receptor (ET(B)R) antagonist, BQ-788, prevented the stimulatory effect of ET-1 on SOCS-3 gene expression. The specific inhibitors of either MEK1 (U-0126 and PD-98059), JAK (AG-490), JNK (SP-600125), or PI3K (LY-294002 and wortmannin) reduced ET-1-increased levels of SOCS-3 mRNA and respectively inhibited ET-1-stimulated activities of MEK1, JAK, JNK, and PI3K. These results imply that the ET(A)R, ERK, JAK, JNK, and PI3K are functionally necessary for ET-1's stimulation of SOCS-3 gene expression. Moreover, ET-1 was observed to upregulate expressions of SOCS-1, -2, -3, -4, -5, and -6 mRNAs, but not SOCS-7 or cytokine-inducible SH2-containing protein-1 mRNAs. This suggests that ET-1 selectively affects particular types of SOCS family members. Changes in SOCS gene expressions induced by ET-1 may help explain the mechanism by which ET-1 modulates hormone signaling of adipocytes.

The clinicopathological significance of colorectal mucinous carcinoma is controversial, although some authors feel mucinous carcinoma has a worse prognosis than that of non-mucinous carcinoma. To clarify the significance of this type of carcinoma in Taiwan, a retrospective review of patients with colorectal carcinoma treated at Chang Gung Memorial Hospital between 1984 and 1988 was undertaken. During this period, 53 mucinous carcinomas and 401 non-mucinous carcinomas fulfilling the inclusion criteria were analysed. Mucinous carcinomas were more common in patients 39 years of age or under (P < 0.005). Most mucinous carcinomas were located in the rectum/rectosigmoid, followed by the right colon; however, the right colon had a higher relative incidence (38 vs 8%, respectively; P < 0.005). Mucinous carcinomas presented at a significantly more advanced stage (23 vs 8%, respectively, stage D disease; P < 0.005) and had a markedly lower curative resection rate (68 vs 84%, respectively; P < 0.05). Following curative resection, mucinous carcinomas tended to have an increased incidence of subsequent distant metastasis (27.8 vs 18.8%, respectively; P < 0.005). The overall survival rate of patients with mucinous carcinoma was worse than that of non-mucinous carcinoma (P < 0.005). Multivariate analysis showed that clinically important predictive factors were stage of disease on diagnosis and subsequent distant metastasis. The mucinous histological type itself was not an independent prognostic factor in colorectal cancer.

We present a case of pancreatic ascites. The diagnosis was strongly suspected on the basis of ascitic fluid analysis and was confirmed by observation of pancreatic duct contrast leakage at endoscopic retrograde pancreatography (ERP). Computed tomography was not helpful in this case. For localization and final confirmation of the lesion, ERP is the most valuable investigative method.

In order to more specifically define gallbladder carcinoma with real-time ultrasonography, a retrospective study was performed involving 29 sonographically false-negative and 22 sonographically false-positive cases of gallbladder carcinoma. Among the false negative cases, 18 (62.1%) were diagnosed as gallbladder stone only, 6 cases (20.7%) were incorrectly diagnosed as either acute or chronic cholecystitis, 2 cases (6.9%) were diagnosed as bile sludge, 2 cases (6.9%) were diagnosed as polyps, and 1 case (3.4%) was diagnosed as liver tumor. In false-positive cases, 8 (31.8%) were erroneously diagnosed as liver tumor. In false-positive cases, 7 (31.8%) were erroneously diagnosed as a mass projecting from the gallbladder wall but were pathologically proven to be polyps (4 cases) or bile sludge (3 cases); 8 cases (36.4%) were incorrectly diagnosed due to irregular thickening of the gallbladder wall but histology revealed them to be acute (3 cases) or chronic (5 cases) cholecystitis. Seven cases (31.8%) had a solid mass in porta hepatis, indicating gallbladder carcinoma; of these, 2 cases were lumps of bile sludge and 5 cases were acute cholecystitis with empyema. The differentiation of gallbladder carcinoma from cholecystitis (acute or chronic), polyps, and bile sludge is sometimes very difficult. With an understanding of the sonographic pitfalls and difficulties in the diagnosis of gallbladder carcinoma, a more specific diagnosis may be made.

Ultrasonography of prospectively followed chronic hepatitis B patients who developed liver cirrhosis were reevaluated in order to identify the ultrasonographic changes of early cirrhosis. Ultrasonographic features of 29 patients before and after cirrhosis were as follows: portal vein diameter--1.20 cm/1.29 cm (NS); cirrhosis score--5.69/7.52 (p < 0.01); spleen size index--21.99 cm2/25.84 cm2 (NS). The result suggests that ultrasonographic diagnosis of early cirrhosis is not easy on a single occasion; however, the score system method is helpful in longitudinal follow-up chronic hepatitis patients. A careful comparison of hepatic parenchymal and surface changes are mandatory.

A rare case of intrahepatic-cutaneous biliary fistula resulted from obstruction of the biliary tree by cholangiocarcinoma in the hilar area. The diagnosis was made clinically by the presence of a constant pus discharge through the fistula opening and confirmed by sonogram, computed tomogram (CT), and surgery. To our knowledge, there have been no previous reports of such a fistula as the presenting symptom of cholangiocarcinoma.

The authors report the case of a hepatic metastatic squamous cell carcinoma, from an unknown primary, which mimicked multiple liver cysts. The literature is also reviewed.

Myelolipoma is a rare, benign, endocrinologically nonfunctioning adrenal tumor composed of fatty tissue with foci of hematopoietic cells. Clinical diagnosis and surgical removal are extremely rare. We report a case of large myelolipoma (10 x 6 x 6 cm) that was removed surgically in a 54-year-old man in whom the mass was studied preoperatively by sonogram, CT and angiography.

Melanosis duodeni is a rare benign condition that has only recently been recognized. We describe melanosis duodeni in a 64-year-old woman who had been taking propranolol and furosemide for 5 years. The cause and clinical significance of this unusual finding remain obscure. But we assume that it is an idiosyncratic metabolism of benzene-ring-containing drugs resulting in the accumulation of pigment in the duodenal mucosa.

A 47-year-old male suffered spontaneous intramural perforation of his esophagus following tracheostomy and nasogastric intubation. The reports of this unusual lesion in the literature are reviewed, and the characteristic radiographic and endoscopic features demonstrated.