Tafazzin (TAZ) promotes the tumorigenicity of cervical cancer cells and inhibits apoptosis

<div><p>Tafazzin (TAZ) is often aberrantly expressed in some cancers, including rectal cancer and thyroid neoplasms. However, the function of TAZ in cervical cancer cells remains unknown. This study aims to explore the expression and function of TAZ in cervical cancer cells. Here, we determined the expression of TAZ protein in normal cervical tissue (NC, n = 27), high-grade squamous intraepithelial lesions (HSIL, n = 26) and squamous cervical carcinoma (SCC, n = 41) by immunohistochemistry, the expression of TAZ protein gradually increased from NC to HSIL to SCC. TAZ was overexpressed or down-regulated in cervical cancer cells by stably transfecting a TAZ-expressing plasmid or a shRNA plasmid targeting TAZ. <i>In vitro</i>, the cell growth curves and MTT assays showed that TAZ may promote the growth and viability of cervical cancer cells. <i>In vivo</i>, xenografts experiment showed that TAZ may increase tumor-forming ability. The percentage of apoptosis cells analyzed by FACS and TUNEL assays consistently showed that TAZ inhibits apoptosis in cervical cancer cells. Furthermore, the Cleaved Caspase 9 and Cleaved Caspase 3 were down-regulated by TAZ in cervical cancer cells. Taken together, this study demonstrated that TAZ is overexpressed in cervical cancer and may promote tumorigenicity of cervical cancer cells and inhibit apoptosis.</p></div

C3d and C5b-9 deposition at the retina/choroidal interface of different strains of mice.

<p>Cryosections of eyes from 22–24-month old mice were stained for C3d (red) or C5b-9 (green in F and G) and observed by confocal microscopy. A, an image from a 22-momth old WT mouse. B, an image from a 22-momth old CCR2 KO mouse. C, an image from a 22-momth old CCL2 KO mouse. D and E, images taken from a 24-momth old CCL2 KO mouse showing area of RPE cell death (asterisks) and extensive C3d deposition (red). F and G, images taken from a 24-momth old CCR2 KO mouse (F) and a 24-month old CCL2 KO mouse showing areas of RPE cell death (arrows) with C3d deposition (red), but no C5b-9 deposition (green). H, a retina from a mouse with EAU <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0022818#pone.0022818-Xu2" target="_blank">[25]</a>, <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0022818#pone.0022818-Copland1" target="_blank">[35]</a> was used as positive control for C5b-9 staining (green). I, Isotype control antibody staining for C3d in a 24-month CCL2 KO mouse showing no background staining. ONL, outer nuclear layer. RPE, retinal pigment epithelia. Ch, choroid.</p

Phenotype and function of myeloid-derived cells in different strains of mice.

<p>A, Bone marrow and blood cells collected from different strains of mice were stained for different cell surface markers and analysed by flow cytometry. Mean ± SEM, N = 6. B, Cytokine gene expression in LPS stimulated BM-DMs of different strains of mice. Mean ± SEM, N = 3. *, P<0.05; **, P<0.01; compared to WT cells. Unpaired Student t test. Experiments were performed four times. C–D, Nitrotyrosine (green) and PI (red) staining in the eye of a 20-month old WT mouse (C) and a 20-month old CCL2 KO mouse (D). E, isotype control staining. Ch, choroid; RPE, retinal pigment epithelium. F, Endocytosis of BM-DMs using dextran method (see Materials & Methods). MFI, mean fluorescence intensity. G, Phagocytosis of E. coli by BM-DMs (see Materials & Methods). Mean ± SEM, N = 3. *, P<0.05, **, P<0.01 compared to WT cells of the same time point. Dunnett Multiple comparison test. Experiments were performed twice.</p

TEM images of RPE/photoreceptor of different strains of mice.

<p>A, an image from a 22-month old WT mouse showing RPE basal laminar deposits (asterisk). B, an image from 22-month old CCR2 KO mouse showing a photoreceptor outer segment (arrowhead) in parallel with RPE cells, multiple vacuoles (white arrows) in RPE cells and basal laminar deposits (asterisk). C, an image from a 22-month old CCL2 KO mouse showing multiple vacuoles in RPE cells (white arrows) and basal laminar deposits (asterisk). D, an image from a 24-month old CCL2 KO mouse showing multiple vacuoles and reduced melanin granules in degenerated RPE cells, basal laminar deposits (asterisk). E, an image from a 24-month old CCR2 KO mouse showing photoreceptor inner segment degeneration (black arrows), and a gap between RPE cells and photoreceptor outer segments. F, an image from a 20-month old CCL2 KO mouse showing photoreceptor inner segment degeneration (black arrows), reduced melanin granules in RPE cells and RPE basal laminar deposition (asterisk). G, an image from a 20-month old CCL2 KO mouse showing a patch of RPE atrophy, disorganised photoreceptor outer segments, a lack of choriocapillaris, and fibrotic tissues in the choroid (black asterisks). H and I, images from a 24-month old CCL2 KO mouse showing the loss of electron-dense materials in the cytoplasm, the loss of cytoplasm organelles and membrane, and a nucleus with reduced electron-dense materials in the RPE layer; choriocapillaris basal laminar deposition in the choroid; a layer of melanin granule-containing cells (block arrowheads) on top of the degenerated RPE cells with their process extending towards the photoreceptor outer segments. RPE, retinal pigment epithelia. (J), A confocal image of RPE/choroidal flatmount of a 24-month CCL2 KO mouse showing accumulation of macrophages/microglia at the site of RPE damage. RPE damages were highlighted with disorganised actins (phalloidin staining) and subretinal macrophages were labelled with Iba-1.</p

Primers used in real-time PCR.

<p>Primers used in real-time PCR.</p

Phenotypes and functions of BM-DCs of different strains of mice.

<p>A, The expression of CD11b and CD11c in bone marrow-derived dendritic cells (BMDCs) of different strains of mice. B, cytokine production by immature BM-DCs (iDC) and mature BM-DCs (mDC) of different strains of mice. C, endocytosis of FITC-dextran by iDC of different strains of mice. Mean ± SEM, n = 4. *, P<0.05, **, P<0.01 in comparison to WT cells. n = 4, unpaired Student t test.</p