thymosin-beta(4) and Uterine-Cervical-Neoplasms

Thymosinβ-4(Tβ4) is an actin-sequestering protein involved in tumor malignancy. Primary cilia, microtubule-based organelles, are present in most eukaryotic cells, which might be related to tumor cell transformation. Here, we investigated whether ciliogenesis is affected by Tβ4 in HeLa human cervical cancer cells. The inhibition of Tβ4 attenuated primary cilia formation. The frequency of cilia was increased by Tβ4 overexpression. When yeast two-hybrid assay was performed by using Tβ4 as a bait, we rescued nephronophthisis 3(NPHP3), one of the components of primary cilia. Interaction of Tβ4 with NPHP3 in mammalian cells was confirmed by GST-pulldown assay. Their intracellular co-localization was observed by immunofluorescence staining at peripheral surface of cells. In addition, the number of ciliated cells was reduced by the inhibition of NPHP3. Moreover, NPHP3 expression was decreased by the inhibition of Tβ4 but it was increased by Tβ4 overexpression. Taken together, the results demonstrate that primary cilia formation could be regulated by Tβ4 through its interaction with NPHP3 and/or the control of NPHP3 expression. It suggests that Tβ4 is a novel regulator for primary cilia formation by NPHP3. It also suggests that tumorigenesis could be associated with inappropriate regulation of Tβ4 and/or NPHP3 expression to maintain primary cilia formation normally.

Topics: Cilia; Female; HeLa Cells; Humans; Kidney Diseases, Cystic; Promoter Regions, Genetic; Thymosin; Uterine Cervical Neoplasms

Recent studies have shown that thymosin β4 (TB-4) is highly related with tumor metastasis and angiogenesis. In addition, TB-4 induced the expression of VEGF in melanoma cells. We investigated the expression patterns of TB-4 and related angiogenic proteins, VEGF, and HIF-1α, at various stages of cervical cancers and also identified the expression pattern of these proteins in metastatic cervical cancers. Expression patterns of TB-4, VEGF, and HIF-1α were studied with tissue microarray containing 42 samples of cervical cancers. In addition, 15 cervical cancers and metastatic tumors in lymph nodes from patients who have metastatic tumors were also analyzed to confirm the role of TB-4, VEGF, and HIF -1α in cervical cancer metastasis. The expression levels of TB-4, VEGF, and HIF-1α were very weak at early cancer stages (stages 0 to 1A) but significantly increased at stage 1B. The numbers of blood vessels in tumors were also increased at stage 1B. The expression patterns of TB-4, VEGF, and HIF-1α were compared in tumors without lymph node metastasis, primary tumors with lymph node metastasis, and metastatic tumors in lymph nodes. The expression levels of TB-4, VEGF, and HIF-1α in primary tumors with lymph node metastasis and their metastatic tumors in lymph node were less than in tumors without lymph node metastasis. These data suggest that TB-4, VEGF, and HIF-1α triggered angiogensis and tumor invasiveness to surrounding tissues at early stage of cervical carcinoma but have a negative or no effect on the metastatic potential.

Topics: Biomarkers, Tumor; Carcinoma, Squamous Cell; Case-Control Studies; Cervix Uteri; Female; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Immunoenzyme Techniques; Lymphatic Metastasis; Neoplasm Staging; Neovascularization, Pathologic; Prognosis; Thymosin; Tissue Array Analysis; Uterine Cervical Neoplasms; Vascular Endothelial Growth Factor A

Thymosin beta-4 (TB4) is an actin-sequestering protein to control cytoskeletal reorganization. Here, we investigated whether TB4 proteins (TB4P) affect tumor microenvironment by measuring hypoxia-inducible transcription factor (HIF)-1 alpha stabilization in cervical tumor cells, since TB4P reduced paclitaxel-induced cell death rate. TB4P increased HIF-1 alpha stabilization and transactivation, which is measured by the increase of hypoxia response element (HRE)-luciferase activity and target gene, vascular endothelial growth factor (VEGF) transcription. TB4P also elevated ERK phosphorylation. PD98059, ERK inhibitor reduced HIF-1 alpha increased by TB4P. Paclitaxel-induced cell death was inhibited by hypoxia conditioning that increased HIF-1 alpha stabilization and ERK phosphorylation. PD98059 reversed paclitaxel-induced cell death which was attenuated by hypoxia. Collectively, TB4P could lead tumor cell microenvironment to hypoxia condition, which might be resulted in antitumor drug-resistance induction. It suggests that soluble TB4P could be a novel target to control tumor cell death by regulating tumor cell microenvironment.

Topics: Actins; Antineoplastic Agents, Phytogenic; Blotting, Western; Cell Hypoxia; Cell Survival; Drug Resistance, Neoplasm; Extracellular Signal-Regulated MAP Kinases; Female; HeLa Cells; Humans; Hypoxia-Inducible Factor 1, alpha Subunit; Paclitaxel; Phosphorylation; Reverse Transcriptase Polymerase Chain Reaction; Signal Transduction; Thymosin; Uterine Cervical Neoplasms