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Cancerous inhibitor of protein phosphatase 2A (CIP2A) is an oncoprotein overexpressed in human malignancies, including prostate cancer (PCa). In this study, we aimed to explore the oncogenic function of CIP2A in PCa cells and its underlying mechanism. We showed that 63.3% (38/60 cases) of PCa tissues exhibited a high CIP2A immunostaining, compared to 25% (3/12 cases) of BPH samples (p = 0.023). Furthermore, the protein level of CIP2A was positively correlated with patients’ short survival time and nuclear AR levels in PCa tissues. Compared to PZ-HPV-7, an immortalized prostate cell line, androgen-sensitive LNCaP C-33, androgen-independent LNCaP C-81, or 22Rv1 cells exhibited a high CIP2A level, associated with high protein and phosphorylation levels of AR. While AR expression and activity modulated CIP2A expression, manipulating CIP2A expression in PCa cells regulated their AR protein levels and proliferation. The reduction of CIP2A expression also enhanced the sensitivity of PCa cells toward Enzalutamide treatment. Our data further showed that depletion of polo-kinase 1 (PLK1) expression or activity in C-81 or 22Rv1 cells caused reduced protein levels of c-Myc and AR. Notably, inhibition of PLK1 activity could abolish CIP2A-promoted expressions in c-Myc, AR, and prostate-specific antigen (PSA) in C-33 cells under an androgen-deprived condition, suggesting the role of PLK1 activity in CIP2A-promoted AR expression. In summary, our data showed the existence of a novel regulation between CIP2A and AR protein levels, which is critical for promoting PCa malignancy. Thus, CIP2A could serve as a therapeutic target for PCa.

In the field of precision machining, temperature fluctuation tends to cause the most significant machining errors. In particular, heat, which is generated in the nut of the ball screw feed system during movement, can deform the screw shaft significantly. In order to calculate and evaluate the thermal deformation of the ball screw shaft, the rate of the heat transfer from the nut to the screw shaft must be known. This rate can be calculated by subtracting the heat transfer rate to the nut raceway from the heat generation rate of the nut. Hence, it is necessary to calculate the heat flux from the nut to the nut raceway. This paper introduces a novel method to calculate the heat flux from the nut to the nut raceway. The new approach also enables calculations for different operating conditions. Furthermore, an experimental setup is established to measure the temperature increase, from 0 to 180 s after the nut starts moving, for various operating conditions. It is then theoretically shown that the 0–180 s temperature increase/heat flux curves for the nut are “universal”, i.e., the curve remains unchanged for the different operating conditions. Subsequently, a thermal model using the finite element method (FEM) is developed to simulate the nut temperature increase over time, which is then compared with the experimental data. As a result, it becomes possible to determine the heat flux from the nut to the nut raceway and calculate the 0–180 s temperature increase/heat flux curve (ΔT˜0~180s,TrainingData) for the training group. Finally, the heat flux from the nut to the nut raceway is calculated for ten different operating conditions in the test group using the 0–180 s temperature increase/heat flux curve of the training group (ΔT˜0~180s,TrainingData). The corresponding temperature curves are then calculated by inputting the values of the heat fluxes into the FEM model. The highest root mean square error (RMSE) between the calculated and experimentally measured temperature increase was 0.16 °C for Test 7 (the error was 10.7%). This result indicates that the new method is valid and feasible for calculating the heat flux from a ball screw nut to the nut raceway.

Among the errors in precision machining, thermal error has been recognized as the most significant error. The heat of the nut in the feed drive system plays an important role in the thermal error generated by the feed drive system. To better estimate and further understand the increase in temperature and thermal deformation of the ball screw during operation, a new correlation equation for the frictional torque of the nut is proposed and determined in this study for the calculation of the frictional torque of the nut and the heat generated by the nut at different feed velocities and nut temperatures. In this study, a set of devices for measuring the frictional torque of the nut under different feed velocities and different nut temperatures is designed and established. Various experimental conditions are designed to measure the frictional torque of the nut at different feed velocities and different nut temperatures to establish a correlation equation for the frictional torque of the nut. In addition, for further confirmation, the method for measuring the frictional torque of the nut used in this study is compared with the method using a handheld digital force gauge. The correlation equation for the frictional torque of the nut established in this study is based on the LuGre model and the formula of the frictional torque due to the viscosity of the lubricant of the bearing at different temperatures. The results show that the root-mean-square error between the frictional torque of the nut calculated by the correlation equation and that measured experimentally is 0.0301 N-m, indicating that the correlation equation for the frictional torque of the nut proposed in this study is accurate and feasible.

Retinopathy is a well-known ocular complication that occurs in patients with type 2 diabetes (T2D). Recent evidence also indicates that diabetic patients have an increased prevalence of dry eye syndrome. However, the etiologies of both diabetic retinopathy (DR) and dry eye disease are complex, and their associations with T2D remains to be fully understood. Patient-derived human induced pluripotent stem cells (hiPSCs) enable the generation of disease-specific retinal tissues such as retinal pigment epithelium and lacrimal gland to model disease pathogenesis. Here, we describe the establishment of three hiPSC lines from T2D patients with PDR or dry eye disease.

Type 1 diabetes (T1D) is characterized by the autoimmune destruction of insulin-producing β cells. Genetic studies have identified > 60 T1D risk loci that harbor genes with disease-causative alleles. However, determining the biological effects of such loci is often difficult due to limited tissue availability. Disease-specific human induced pluripotent stem cells (hiPSCs) are a valuable resource for modeling T1D pathogenesis. In particular, families with complete disease penetrance offer an opportunity to further dissect T1D risk loci. Here, we describe the generation of three hiPSC lines from a T1D family with sequence variants associated with autoimmunity.

Background & Aim Induced pluripotent stem cells (iPSCs), which can be generated from patients’ somatic cells and grown in cultures maintaining their pluripotency and possessing the unlimited self-renewal capability, have been utilized for developing cell therapeutic strategies, dissecting disease mechanisms and validating drug response. Recent studies imply pluripotent stem cells (PSCs) possess a unique metabolic features and require specific metabolites in maintaining their cell fate. In the current work, we have deciphered the specific metabolites required for maintaining self-renewal expansion of iPSCs. Methods, Results & Conclusion Utilizing RNA-Seq analysis, we showed that, in comparing with fibroblast, ESCs and iPSCs were found to retain the expression of critical enzymes involved in Krebs cycle. We then determined if the specific bioenergetics adaptation in cultures can affect pluripotency acquirement or maintenance. Oct4-GFP(+) iPSCs derived mouse fibroblast were seeded in medium containing either 4500mM Glucose (high glucose) with or without Oligomycin (mitochondrial ATPase inhibitor), 500mM Glucose (low glucose) and 0mM Glucose (no glucose) with or without pyruvate (to be utilized in TCA cycles). We found that depletion of glucose resulted in reduced growth of Oct4-GFP(+) iPSC colonies. In contrast, addition of pyruvate could rescue the growth of Oct4-GFP(+) iPSC colonies suggesting the retaining mitochondrial respiration may aid self-renewal expansion of pluripotent stem cells. The further analysis revealed that mouse and human ESCs/iPSCs had evaluated level of GLUT5 & KHK suggesting pluripotent stem cells can utilize fructose efficiently. We further validated that fructose substitution was sufficient to maintain the self-renewal growth of ESCs/iPSCs. Importantly, fructose substitution was found to enhance generation of iPSCs from Yamanaka factor mediated fibroblast reprogramming possibly via selectively suppressing the growth of partial reprogrammed cells and upregulating alpha 2,6-sialylation as sialyltransferase ST6Gal1 is known to play an crucial role in regulating pluripotency. In summary, the current work elucidated that the specific bioenergetics adaptation in cultures linking to pluripotency maintenance and identified ESCs/iPSCs can utilize fructose efficiently. Fructose substitution can therefore be used to enhance derivation of iPSCs.

Transcriptionally non-co-linear (NCL) transcripts can originate from trans-splicing (trans-spliced RNA; ‘tsRNA’) or cis-backsplicing (circular RNA; ‘circRNA’). While numerous circRNAs have been detected in various species, tsRNAs remain largely uninvestigated. Here, we utilize integrative transcriptome sequencing of poly(A)- and non-poly(A)-selected RNA-seq data from diverse human cell lines to distinguish between tsRNAs and circRNAs. We identified 24,498 NCL events and found that a considerable proportion (20–35%) of them arise from both tsRNAs and circRNAs, representing extensive alternative trans-splicing and cis-backsplicing in human cells. We show that sequence generalities of exon circularization are also observed in tsRNAs. Recapitulation of NCL RNAs further shows that inverted Alu repeats can simultaneously promote the formation of tsRNAs and circRNAs. However, tsRNAs and circRNAs exhibit quite different, or even opposite, expression patterns, in terms of correlation with the expression of their co-linear counterparts, expression breadth/abundance, transcript stability, and subcellular localization preference. These results indicate that tsRNAs and circRNAs may play different regulatory roles and analysis of NCL events should take the joint effects of different NCL-splicing types and joint effects of multiple NCL events into consideration. This study describes the first transcriptome-wide analysis of trans-splicing and cis-backsplicing, expanding our understanding of the complexity of the human transcriptome.

Androgen receptor (AR) is a steroid hormone receptor that functions as a transcription factor for regulating cell growth and survival. Aberrant AR function becomes a risk factor for promoting the progression of prostate cancer (PCa). In this study, we examined the roles of proline-rich tyrosine kinase 2 (PYK2) and ribosomal S6 kinase 1 (S6K1) in regulating AR expression and activity and growth properties in PCa cells. Compared with normal prostate tissues, PCa tumors exhibited high levels of PYK2 and S6K1 expression. Furthermore, the expression levels of PYK2 and S6K1 were significantly correlated with nuclear AR expression in PCa tissues. We further found the association between PYK2, S6K1, and AR in their protein expression and phosphorylation levels among normal prostate PZ-HPV-7 cells and prostate cancer LNCaP and 22Rv1 cells. Overexpression of the wild-type PYK2 in PZ-HPV-7 and LNCaP cells promoted AR and S6K1 expression and phosphorylation as well as enhanced cell growth. In contrast, expression of the mutated PYK2 or knockdown of PYK2 expression in LNCaP or 22Rv1 cells caused reduced expression or phosphorylation of AR and S6K1 as well as retarded cell growth. Under an androgen-deprived condition, PYK2-promoted AR expression and phosphorylation and PSA production in LNCaP cells can be abolished by knocking down S6K1 expression. In summary, our data suggested that PYK2 via S6K1 activation modulated AR function and growth properties in PCa cells. Thus, PYK2 and S6K1 may potentially serve as therapeutic targets for PCa treatment.