Identical expression profiling of human and murine TIPE3 protein reveals links to its functions

Abstract

Tumor necrosis factor-alpha-induced protein-8 like-3 (TNFAIP8L3, TIPE3) is a newly discovered member of TNFAIP8 family and regarded as a lipid second messenger transfer protein that promotes cancer. Yet the nature of the cells and tissues that express TIPE3 protein has not been determined. In this study, we examined TIPE3 expression in various murine and human tissues by immunohistochemistry and quantitative PCR. We found that TIPE3 expression was almost identical in most organs from human and mice. TIPE3 is a cytoplasmic protein expressed preferentially in epithelial-derived cells with secretory functions. Furthermore, TIPE3 protein is highly expressed in most human carcinoma cell lines. These results suggest that TIPE3 may play important roles in carcinogenesis and cell secretion.

Keywords: TNFAIP8L3 (TIPE3); carcinogenesis; expression; secretion.

Figure 1.

TIPE3 protein in reproductive system and brain of C57BL/6 mice by IHC. In the ovary, TIPE3 protein was observed in oocytes, follicular cells and granulose lutein cells (A1, 400×; A2, 400×). In the oviduct, TIPE3 protein was observed in the epithelium (B1, 400×). In the ductus deferens, TIPE3 protein was observed in the epithelial cells (C1, 100×; C2 400×). In epididymal tissue, TIPE3 protein was detected in spermatozoa (D1, 400×). In the prostate gland, TIPE3 staining was detected in the epithelium (F1, 400×). In brain, TIPE3 protein was detected in the neurons of the grey matter (E1, 400×; E2 400×). A3, B2, C3, D2, E3 and F2: no staining was detected using the rabbit isotype control antibody (400×) for ovary, oviduct, ductus deferens, epididymal, brain and prostate gland tissues, respectively. Scale (C1), 80 μm; all others, 20 μm.

Figure 2.

TIPE3 protein in the gastrointestinal system and cardiac muscle of C57BL/6 mice by IHC. In the esophagus, TIPE3 protein was found in the stratified squamous epithelium (A1, 400×; A2, 400×). In the salivary gland, TIPE3 protein was detected in ducts (B1, 400×). In stomach, TIPE3 protein was observed both in the glandular and nonglandular portions (C1, 100×; C2, 400×; D1, 400×). In the small intestine, TIPE3 protein was detected in the mesenchyme (E1 400×, E2 400×). TIPE3 protein was detected in cardiac muscle (F1, 400×). A3, B2, C3, D2, E3 and F2: no staining was detected with the rabbit isotype antibody (400×) for esophagus, salivary gland, glandular and nonglandular portions of the stomach, small intestine and cardiac muscle. Scale (C1), 80 μm; all others, 20 μm.

Figure 3.

TIPE3 protein in urinary, endocrine and respiratory systems of C57BL/6 mice by IHC. In kidney tissues, TIPE3 was detected in the glomeruli and in the tubular epithelial cells of the proximal convoluted tubules and distal convoluted tubules (A1, 400×; A2, 400×). In the urinary bladder, TIPE3 protein was detected in the transitional epithelium (B1, 400×). In pancreas, TIPE3 protein was observed in the islets, but not in pancreatic acini (C1, 400×; C2, 400×). In the adrenal gland, TIPE3 protein was detected in the medulla (D1, 400×). In the lung, TIPE3 protein was observed in the alveolar cells and the epithelium of the bronchus (E1, 400×; E2 400×). In the trachea, TIPE3 protein was detected in the pseudostratified ciliated columnar epithelium and hyaline cartilage (F1, 400×). A3, B2, C3, D2, E3 and F2: no staining was detected with the rabbit isotype antibody (400×) for, kidney, urinary bladder, pancreas, adrenal gland, lung and trachea, respectively. Scale, 20 μm.

Figure 4.

TIPE3 protein in human gastrointestinal, hemicerebrum and endocrine systems by IHC. In the stomach, TIPE3 was observed in the mucosa (A1, 400×). In the small intestine, TIPE3 protein was detected in the mesenchyme (B1, 400×). In the colon, TIPE3 was detected in the simple columnar epithelium and glands (C1, 400×). In the central nervous system, TIPE3 was detected in grey matter neurons (D1, 400×). In the adrenal gland, TIPE3 was observed in the medulla (E1, 400×). In the pancreas, TIPE3 was observed in the islets (F1, 400×). A2, B2, C2, D2, E2 and F2: no staining was detected with the rabbit isotype antibody (400×) for stomach, small intestine, colon, hemicerebrum, adrenal gland and pancreas, respectively. Scale, 20 μm.

Figure 5.

TIPE3 protein in human kidney, respiratory system, reproductive organs and other organs by IHC. In the kidney, TIPE3 was detected in the glomeruli and in the tubular epithelial cells of the proximal and distal convoluted tubules (A1, 200×). In the trachea, TIPE3 protein was detected in the pseudostratified ciliated columnar epithelium (B1, 400×). In the lung, TIPE3 protein was observed in the alveolar cells (C1, 400×). In the testis, TIPE3 protein was observed in spermatogonia, primary spermatocytes, secondary spermatocytes and spermatozoa (D1, 400×). In the prostate gland, TIPE3 staining was detected in the epithelium (E1, 400×). In the uterus, TIPE3 protein was detected in the uterine glands (F1, 400×). In the skin, TIPE3 protein was detected in the epithelium (G1, 400×). TIPE3 protein expression was low in cardiac muscle and was not detected in skeletal muscle (H1, 400×; I1, 400×). A2, B2, C2, D2, E2, F2, G2, H2, I2, J3 and K3: no staining was detected with the rabbit isotype antibody (400×; A2 200×) for kidney, trachea, lung, testis, prostate, uterus, cardiac muscle and skeletal muscle, respectively. Scale (A1 and A2), 40 μm, others 20 μm.

Figure 6.

TIPE3 mRNA in cell lines. TIPE3 mRNA levels were detected in human cell lines by RT-PCR (A and B) and real-time PCR (C and D). The highest TIPE3 mRNA expression was detected in human HMy2.CIR cells and HEK293 cells. Moderate or weak TIPE3 expression was detected in most human carcinoma cell lines. (E) Antibody specificity controls.