N-cadherin and p21 transcript and protein expression levels in HSC5 cells treated with arsenic.

<p>A and C) transcript expression levels of N-cadherin and p21 were measured by real-time PCR. ***, significantly different (p<0.001) from the control by Student's t-test. B and D) Protein expression levels of N-cadherin and p21 were measured by immunoblot. TUBULIN was used as a positive control. Three independent experiments were performed and the same results were obtained.</p

Effects of arsenic on invasion of HSC5 cells.

<p>Invasive ability of of HSC5 cells treated 0, 1.0, 3.0 and 5.0 µM of arsenic were evaluated by invasion assay. Number of invading HSC5 cells treated with arsenic in the invasion assay were presented in photographs (A) and a graph (B). **, Significantly different (p<0.01) from the control by the Student's t-test.</p

MT1-MMP and P14 transcript and protein expression levels in HSC5 cells treated with arsenic.

<p>A and C) transcript expression levels of MT1-MMP and p14 were measured by real-time PCR. **, significantly different (p<0.01) from the control by Student's t-test. B and D) Protein expression levels of MT1-MMP and p14 were measured by immunoblot. TUBULIN was used as a positive control. Three independent experiments were performed and the same results were obtained.</p

Effects of arsenic on invasive activity and phosphorylation and/or expression levels of MT1-MMP and ERK 4 in HSC5 cells.

<p>A), Invasive activity of HSC5 treated with 3 µM of arsenic was evaluated invasion assay. Level of invasive ability is presented as number of invading cells in a graph (left) and photographs (right). **, Significantly different (p<0.01) from the control by the Student's t-test. Phosphorylated levels of ERK (P-ERK) and protein expression levels of MT1-MMP and ERK in HSC5 cells treated with 3 µM arsenic for 24 hours are presented. TUBULIN protein expression levels are presented as an internal control.</p

Effects of arsenic on apoptosis of HSC5 cells.

<p>Viability of HSC5 cells treated with 0, 1.0, 3.0 and 5.0 µM of arsenic was evaluated by crystal violet (CV). Cells were presented in photographs (A) and ratios of arsenic treated live cells and control live cells were presented in a graph (B). **, Significantly different (p<0.01) from the control by the Student's t-test.</p

Levels of c-RET protein expression in human malignant melanoma cell lines.

<p>The levels of c-RET protein expression were examined in c-RET-transfected NIH3T3 cells as a positive control (c-RET transfectant; lane 1), primary-cultured normal human epithelial melanocytes (NHEM; lane 2), G361 (lane 3), HM3KO (lane 4) and MNT-1 (lane 5) by immunoblotting analysis with anti-RET antibody after immunoprecipitation with anti-RET antibody.</p

Levels of c-RET, GFRa1 and GDNF transcripts expression in primary-cultured normal human epithelial melanocytes (NHEM) and human malignant melanoma cell lines.

<p>(A, B, C) Levels of c-RET (A), GFRa1 (B) and GDNF (C) transcripts expression in NHEM (lane 1) and 4 kinds of malignant melanoma cell lines (lanes 2–5; SK-Mel28, G361, MNT-1 and HM3KO). The transcript levels measured by real-time PCR were adjusted by TATA-box-binding protein (TBP) transcript levels. Differences in expression levels of c-Ret (A), Gfra1 (B) and Gdnf (C) between NHEM (lane 1; open bar) and malignant melanoma cell lines (lanes 2–5; closed bars) were statistically analyzed by the Kruskal-Wallis test. **, Significantly different (P<0.01) from the control.</p

Proliferation of HM3KO cells.

<p>Proliferation of HM3KO cells treated with a solvent (0.1% of DMSO) (open circle in A, lane 1 in B), GDNF (100 ng/ml) (closed circle in A, lane 2 in B), SU5416 (5µM) (open square in A, lane 3 in B) and GDNF plus SU5416 (closed square in A, lane 4 in B) for 24 (A) and 48 hours (A, B) was examined by cell counting with trypan blue staining (A) and MTT assay (B). Difference between proliferation levels of DMSO-treated control cells and other cells was statistically analyzed by the Kruskal-Wallis test. *, Significantly different (P<0.05) from the control.</p

Augmentation of c-RET tyrosine kinase activity in HM3KO cells by c-RET ligand (GDNF).

<p>Expression of c-RET protein (A, B) and phosphorylated tyrosine 905 in c-RET (C, D) in HM3KO cells in the absence (A, C) or presence (B, D) of GDNF were examined by immunocytochemistry with anti-c-RET and anti-phosphorylated tyrosine 905 in c-RET antibodies using hematoxylin counterstaining (A–D).</p

Stage-dependent c-Ret, Gfra1 and Gdnf transcripts expression levels in tumors from RET-mice.

<p>(A, C, E) Levels of c-Ret (A), Gfra1 (C) and Gdnf (E) transcripts expression in tumors of various sizes from RET-mice. Histopathologically benign and malignant tumors are shown by open and closed squares, respectively. (B, D, F) Levels of c-Ret (B), Gfra1 (D) and Gdnf (F) transcripts expression (mean ± SD) in benign melanocytic tumors (open bar) and malignant melanoma (closed bar) from RET-mice. c-Ret (A, B), Gfra1 (C, D) and Gdnf (E, F) transcript levels measured by real-time PCR were adjusted by hypoxanthine guanine phosphoribosyl transferase (Hprt) transcript levels. Differences in expression levels of c-Ret (B), Gfra1 (D) and Gdnf (F) between benign melanocytic tumors and malignant melanoma from RET-mice were statistically analyzed by the Mann-Whitney <i>U</i> test. *, Significantly different (P<0.05) from the control.</p