Knockdown of tumor protein D52-like 2 induces cell growth inhibition and apoptosis in oral squamous cell carcinoma

Heightened TPD52 linked to metabolic dysfunction and associated abnormalities in zebrafish

The tumor protein D52 (TPD52) gene encodes a proto-oncogene protein associated with various medical conditions, including breast and prostate cancers. It plays a role in multiple biological pathways such as cell growth, differentiation, and apoptosis. The function of TPD52 in lipid droplet biosynthesis has been investigated in vitro. However, its precise role in lipid metabolism in animal models is not fully understood. To investigate the functions of TPD52 in vivo, we performed a conditional TPD52 protein expression analysis using a Tet-off transgenic system to establish conditionally expressed Tpd52 transgenic zebrafish. The effect of Tpd52 on lipogenesis was assessed using various methods, including whole-mount Oil Red O staining, histological examination, and measurement of inflammatory markers and potential targets using real-time quantitative polymerase chain reaction and immunoblotting in Tpd52 fish. Zebrafish with increased Tpd52 levels exhibited notable weight gain and the enlargement of fat deposits, which were mainly attributed to an increase in the volume of adipocytes. Moreover, Tpd52 overexpression was correlated with the triggering of the adipocyte differentiation signaling pathway. During adipocytic differentiation in response to nutrient status, our observations revealed adipogenesis, nonalcoholic fatty liver disease, and metabolic cardiomyopathy (MCM) in Tpd52 transgenic zebrafish. To gain a deeper understanding of the contribution of these proteins to the regulation of cellular growth, we investigated the expression of their corresponding genes and proteins in zebrafish. In the present study, the activated protein kinase pathway was identified as the primary target of TPD52. Adult Tpd52 zebrafish showed increased lipid accumulation, resulting in the development of visceral obesity, nonalcoholic fatty liver disease, and MCM. These findings strongly suggest that TPD52 actively contributes to adipose tissue expansion and its subsequent effects. This investigation provides compelling evidence that Tpd52 facilitates adipocyte development and related metabolic comorbidities in zebrafish.

Increased expression of tumor protein D54 is associated with clinical progression and poor prognosis in patients with prostate cancer

Tumor protein D54 (TPD54) has been reported to be involved in the prognosis of several cancers. However, the involvement of TPD54 in prostate cancer (PCa) is yet to be elucidated. In the present study, 117 patients with PCa were enrolled. The mRNA and protein levels of TPD54 in PCa tissues and adjacent normal prostate tissues were analyzed by quantitative polymerase chain reaction and western blotting. TPD54 expression was also determined by immunohistochemistry (IHC) in paraffin-embedded PCa tissues. The association between TPD54 expression and clinicopathological features and prognosis was evaluated. The results revealed that the expression levels of TPD54 mRNA and protein were upregulated in PCa tissues compared with adjacent normal prostate tissues. In addition, moderate/strong staining of TPD54 was observed in 91.4% (107/117) of PCa tissues, but only in 32.5% (38/117) of adjacent normal prostate tissues, as assessed by IHC. TPD54 expression was significantly associated with Gleason score (P=0.0001). In addition, patients with PCa with moderate/strong TPD54 expression had shorter biochemical recurrence-free survival times compared with those with negative/weak TPD54 expression (P=0.002). Multivariate analysis indicated that TPD54 overexpression was an independent prognostic factor for patients with PCa (hazard ratio, 2.259; 95% confidence interval, 1.09-4.679; P=0.028). Taken together, these results indicated that TPD54 is a predictor of poor outcome for patients with PCa, and may be a potential prognostic marker for patients with PCa.

Widespread Use of Misidentified Cell Line KB (HeLa): Incorrect Attribution and Its Impact Revealed through Mining the Scientific Literature

Continuous cell lines are widely used, but can result in invalid, irreproducible research data. Cell line misidentification is a common problem that can be detected by authentication testing; however, misidentified cell lines continue to be used in publications. Here we explore the impact of one misidentified cell line, KB (HeLa), on the scientific literature. We identified 574 articles between 2000 and 2014 that provided an incorrect attribution for KB, in accordance with its false identity as oral epidermoid carcinoma, but only 57 articles that provided a correct attribution for KB, as HeLa or cervical adenocarcinoma. Statistical analysis of 57 correct and 171 incorrect articles showed that the number of citations to these articles increased over time. Content analysis of 200 citing articles showed there was a tendency to describe the cell line in accordance with the description in the cited paper. Analysis of journal impact factor showed no significant difference between correct and incorrect groups. Articles using KB or citing that usage were most frequently published in the subject areas of pharmacology, pharmacy, oncology, and medicinal chemistry. These findings are important for science policy and support the need for journals to require authentication testing as a condition of publication. Cancer Res; 77(11); 2784-8. ©2017 AACR.

Opposite effects of tumor protein D (TPD) 52 and TPD54 on oral squamous cell carcinoma cells

The tumor protein D52 (TPD52) protein family includes TPD52, -53, -54 and -55. Several reports have shown important roles for TPD52 and TPD53, and have also suggested the potential involvement of TPD54, in D52-family physiological effects. Therefore, we performed detailed expression analysis of TPD52 family proteins in oral squamous cell carcinoma (OSCC). Towards this end, TPD54-overexpressing or knocked-down cells were constructed using OSCC-derived SAS, HSC2 and HSC3 cells. tpd52 or tpd53 was expressed or co-expressed in these cells by transfection. The cells were then analyzed using cell viability (MTT), colony formation, migration, and invasion assays. In OSCC-xenograft experiments, the cells were transplanted into nude mice together with injection of anti-tpd siRNAs. MTT assay of cell monolayers showed little differences in growth of the transfected cells. tpd54 overexpression in SAS cells significantly decreased colony formation in an anchorage-independent manner. Additionally, knock-down of tpd54 enhanced the number of colonies formed and overexpression of tpd52 in tpd54 knock-down cells increased the size of the colonies formed. The chemotaxis assay showed that tpd54 overexpression decreased cell migration. In the OSCC-xenograft in vivo study, tpd54 overexpression slightly attenuated tumor volume in vivo, despite the fact that tumor metastasis or cell survival was not involved. Our results showed that TPD54 not only downregulated anchorage-independent growth and cell migration in vitro, but also attenuated tumor growth in vivo. Based on these results, it is considered that TPD54 might act as a negative regulator of tumor progression in OSCC cells.

Tumor Protein D52 (TPD52) Inhibits Growth and Metastasis in Renal Cell Carcinoma Cells Through the PI3K/Akt Signaling Pathway

Tumor protein D52 (TPD52) is a member of the TPD52-like protein family and plays different roles in various types of malignancies. However, its role in renal cell carcinoma (RCC) is still unclear. In this study, we investigated the role of TPD52 in RCC. The mechanism of TPD52 in RCC was also investigated. Our data demonstrated that the expression levels of TPD52 in both mRNA and protein were significantly decreased in RCC cells. Overexpression of TPD52 inhibited proliferation, migration, and invasion with decreased epithelial–mesenchymal transition (EMT) phenotype in RCC cells, as well as attenuated tumor growth in renal cancer xenografts. Mechanistically, overexpression of TPD52 significantly inhibited downregulated phosphorylation levels of PI3K and Akt in RCC cells. In conclusion, the present study demonstrated that TPD52 inhibited growth and metastasis of RCC, at least in part, by suppressing the PI3K/Akt signaling pathway. Therefore, these findings suggest that TPD52 may be a promising therapeutic target for the treatment of human RCC.