Knockdown of Tubulin Polymerization Promoting Protein Family Member 3 Suppresses Proliferation and Induces Apoptosis in Non-Small-Cell Lung Cancer

Carbamazepine-exposed earthworms are characterized by tissue-specific accumulation patterns and transcriptional profiles

Pharmaceutically active compounds enter soils via wastewater reuse and biosolid application. A ubiquitous drug present in wastewater is carbamazepine, a frequently prescribed anti-convulsant. Its mode of action is not species-specific and affects the nervous system of non-target organisms, including most likely the soil dwelling earthworms, which in turn has the potential to negatively impact soil quality. In this project, soils were amended with carbamazepine to explore uptake dynamics and resultant changes in molecular and life cycle endpoints of earthworms (Dendrobaena veneta). Earthworms were maintained, under laboratory conditions, for 28 days in soil spiked with either a solvent control, 0.6 mg/kg carbamazepine (encountered in the terrestrial system) or 10 mg/kg carbamazepine (significantly above an environmental hotspot). Carbamazepine concentrations were quantified in soils and worms by liquid chromatography tandem mass spectrometry (LC-MS/MS) which revealed tissue, dose and time-dependent differences in accumulation. Carbamazepine also modulated the make-up of the microbiome in the soil as well as the earthworm's gut. De novo RNA sequencing identified novel transcripts and complex tissue-specific transcriptomic changes, where, for example, the expression of the tubulin polymerisation promoting protein (tppp) was inhibited (9-fold) in the gut but induced (11-fold) in the cerebral ganglion of exposed earthworms. However, the notable absence of a strong cytochrome P450 response across all conditions suggests that the terrestrial earthworm also relies on detoxification pathways that differ to those observed in well-studied aquatic models. The novel finding that carbamazepine exposure triggers tissue-specific impacts in non-target soil organisms highlights the value and need for a more comprehensive understanding of how contaminants of emerging concern behave within an ecotoxicological context. This, in turn, will lead to informed and reliable risk assessments defining the consequences of wastewater and biosolid amendment practices on soil ecology and ecosystem function.

TPPP3, a Good Prognostic Indicator, Suppresses Cell Proliferation and Migration in OSCC

INTRODUCTION AND AIMS

Oral squamous cell carcinoma (OSCC) is one of the most prevalent malignancy of the head and neck. Early diagnosis of OSCC is difficult and the prognosis has not improved significantly. This study aims to explore the role of tubulin polymerisation promoting protein 3 (TPPP3) in the occurrence and development of OSCC and discover new diagnostic and prognostic markers for OSCC.

METHODS

Using UALCAN, GEPIA, western blot, and quantitative real-time polymerase chain reaction, we studied TPPP3 expression and its relationship with tumour stage. Then, we detected the effect of TPPP3 on OSCC biological functions by CCK-8 and cell scratch assays, as well as correlations between TPPP3 expression and survival of different kinds of head and neck squamous cell carcinoma (HNSC) patients through Kaplan-Meier plotter. Besides, we explored coexpressed genes associated with TPPP3 in HNSC using LinkedOmics and protein-protein interaction networks of TPPP3 using STRING and Cytoscape. Furthermore, we explored possible molecular mechanisms that TPPP3 functions in HNSC using UALCAN, Kaplan-Meier plotter, and TIMER. Finally, we analysed promoter methylation level by UALCAN and mutation by cBioPortal of TPPP3 in HNSC.

RESULTS

TPPP3 was less expressed in OSCC. The TPPP3 expression level was negatively correlated with tumour stage. Furthermore, TPPP3 significantly inhibited OSCC proliferation and migration. Besides, TPPP3 high expression was significantly associated with good prognosis in different kinds of HNSC patients. Additionally, TPPP3 may regulate the occurrence and development of OSCC through the PALMD/PI3K pathway. TPPP3 methylation level in HNSC decreased. Finally, we found that TPPP3 genetic alteration was involved in TPPP3 mRNA expression change in HNSC.

CONCLUSION

TPPP3 functions as a tumour suppressor in OSCC and is associated with good prognosis in HNSC patients. TPPP3 can be used as a potential biomarker for prognosis and diagnosis of OSCC.

CLINICAL RELEVANCE

TPPP3 can be used as a potential biomarker for prognosis and diagnosis of OSCC in clinical practice.

Distinguishing high-metastasis-potential circulating tumor cells through fluidic shear stress in a bloodstream-like microfluidic circulatory system

Circulating tumor cells (CTCs) play a critical role as initiators in tumor metastasis, which unlocks an irreversible process of cancer progression. Regarding the fluid environment of intravascular CTCs, a comprehensive understanding of the impact of hemodynamic shear stress on CTCs is of profound significance but remains vague. Here, we report a microfluidic circulatory system that can emulate the CTC microenvironment to research the responses of typical liver cancer cells to varying levels of fluid shear stress (FSS). We observe that HepG2 cells surviving FSS exhibit a marked overexpression of TLR4 and TPPP3, which are shown to be associated with the colony formation, migration, and anti-apoptosis abilities of HepG2. Furthermore, overexpression of these two genes in another liver cancer cell line with normally low TLR4 and TPPP3 expression, SK-Hep-1 cells, by lentivirus-mediated transfection also confirms the critical role of TLR4 and TPPP3 in improving colony formation, migration, and survival capability under a fluid environment. Interestingly, in vivo experiments show SK-Hep-1 cells, overexpressed with these genes, have enhanced metastatic potential to the liver and lungs in mouse models via tail vein injection. Mechanistically, TLR4 and TPPP3 upregulated by FSS may increase FSS-mediated cell survival and metastasis through the p53-Bax signaling pathway. Moreover, elevated levels of these genes correlate with poorer overall survival in liver cancer patients, suggesting that our findings could offer new therapeutic strategies for early cancer diagnosis and targeted treatment development.

Use of a gene expression signature to identify trimetazidine for repurposing to treat bipolar depression

OBJECTIVES

The aim of this study was to repurpose a drug for the treatment of bipolar depression.

METHODS

A gene expression signature representing the overall transcriptomic effects of a cocktail of drugs widely prescribed to treat bipolar disorder was generated using human neuronal-like (NT2-N) cells. A compound library of 960 approved, off-patent drugs were then screened to identify those drugs that affect transcription most similar to the effects of the bipolar depression drug cocktail. For mechanistic studies, peripheral blood mononuclear cells were obtained from a healthy subject and reprogrammed into induced pluripotent stem cells, which were then differentiated into co-cultured neurons and astrocytes. Efficacy studies were conducted in two animal models of depressive-like behaviours (Flinders Sensitive Line rats and social isolation with chronic restraint stress rats).

RESULTS

The screen identified trimetazidine as a potential drug for repurposing. Trimetazidine alters metabolic processes to increase ATP production, which is thought to be deficient in bipolar depression. We showed that trimetazidine increased mitochondrial respiration in cultured human neuronal-like cells. Transcriptomic analysis in induced pluripotent stem cell-derived neuron/astrocyte co-cultures suggested additional mechanisms of action via the focal adhesion and MAPK signalling pathways. In two different rodent models of depressive-like behaviours, trimetazidine exhibited antidepressant-like activity with reduced anhedonia and reduced immobility in the forced swim test.

CONCLUSION

Collectively our data support the repurposing of trimetazidine for the treatment of bipolar depression.

Proteomics and disease network associations evaluation of environmentally relevant Bisphenol A concentrations in a human 3D neural stem cell model

Bisphenol A (BPA) exposure is associated with a plethora of neurodevelopmental abnormalities and brain disorders. Previous studies have demonstrated BPA-induced perturbations to critical neural stem cell (NSC) characteristics, such as proliferation and differentiation, although the underlying molecular mechanisms remain under debate. The present study evaluated the effects of a repeated-dose exposure of environmentally relevant BPA concentrations during the in vitro 3D neural induction of human induced pluripotent stem cells (hiPSCs), emulating a chronic exposure scenario. Firstly, we demonstrated that our model is suitable for NSC differentiation during the early stages of embryonic brain development. Our morphological image analysis showed that BPA exposure at 0.01, 0.1 and 1 µM decreased the average spheroid size by day 21 (D21) of the neural induction, while no effect on cell viability was detected. No alteration to the rate of the neural induction was observed based on the expression of key neural lineage and neuroectodermal transcripts. Quantitative proteomics at D21 revealed several differentially abundant proteins across all BPA-treated groups with important functions in NSC proliferation and maintenance (e.g., FABP7, GPC4, GAP43, Wnt-8B, TPPP3). Additionally, a network analysis demonstrated alterations to the glycolytic pathway, potentially implicating BPA-induced changes to glycolytic signalling in NSC proliferation impairments, as well as the pathophysiology of brain disorders including intellectual disability, autism spectrum disorders, and amyotrophic lateral sclerosis (ALS). This study enhances the current understanding of BPA-related NSC aberrations based mostly on acute, often high dose exposures of rodent in vivo and in vitro models and human GWAS data in a novel human 3D cell-based model with real-life scenario relevant prolonged and low-level exposures, offering further mechanistic insights into the ramifications of BPA exposure on the developing human brain and consequently, later life neurological disorders.

Cuproptosis Depicts Immunophenotype and Predicts Immunotherapy Response in Lung Adenocarcinoma

BACKGROUND

Although significant progress has been made in immunotherapy for lung adenocarcinoma (LUAD), there is an urgent need to identify effective indicators to screen patients who are suitable for immunotherapy. Systematically investigating the cuproptosis-related genes (CRGs) in LUAD may provide new ideas for patients' immunotherapy stratification.

METHOD

We comprehensively analyzed the landscape of 12 CRGs in a merged TCGA and GEO LUAD cohort. We investigated the associations between tumor microenvironment and immunophenotypes. We utilized a risk score to predict the prognosis and immunotherapy response for an individual patient. Additionally, we conducted CCK-8 experiments to evaluate the impact of DLGAP5 knockdown on A549 cell proliferation.

RESULT

We utilized an integrative approach to analyze 12 CRGs and differentially expressed genes (DEGs) in LUAD samples, resulting in the identification of two distinct CRG clusters and two gene clusters. Based on these clusters, we generated immunophenotypes and observed that the inflamed phenotype had the most abundant immune infiltrations, while the desert phenotype showed the poorest immune infiltrations. We then developed a risk score model for individual patient prognosis and immunotherapy response prediction. Patients in the low-risk group had higher immune scores and ESTIMATE scores, indicating an active immune state with richer immune cell infiltrations and higher expression of immune checkpoint genes. Moreover, the low-risk group exhibited better immunotherapy response according to IPS, TIDE scores, and Imvigor210 cohort validation results. In addition, our in vitro wet experiments demonstrated that DLGAP5 knockdown could suppress the cell proliferation of A549.

CONCLUSION

Novel cuproptosis molecular patterns reflected the distinct immunophenotypes in LUAD patients. The risk model might pave the way to stratify patients suitable for immunotherapy and predict immunotherapy response.

Modulatory Role of TPPP3 in Microtubule Organization and Its Impact on Alpha-Synuclein Pathology

Parkinson’s disease is characterized by locomotion deficits, dopaminergic neuronal loss and alpha-synuclein (SYN) aggregates; the Tubulin Polymerization Promoting Protein (TPPP/p25 or TPPP1) is also implicated in these processes. The moonlighting and chameleon TPPP1 modulates the dynamics/stability of the multifunctional microtubule network by promoting its acetylation and bundling. Previously, we identified the microtubule-associated TPPP3, a homologue of TPPP1 lacking its N-terminus; however, its involvement in physiological or pathological processes was not elucidated. In this work, we have shown the modulatory role of TPPP3, similarly to TPPP1, in microtubule organization, as well as its homo- and hetero-associations with TPPP1. TPPP3, in contrast to TPPP1, virtually does not bind to SYN; consequently, it does not promote SYN aggregation. Its anti-aggregative potency is achieved by counteracting the formation of the TPPP1–SYN pathological complex/aggregation leading to Parkinsonism. The interactions of TPPP3 have been determined and quantified in vitro with recombinant human proteins, cell extracts and in living human cells using different methods including bifunctional fluorescence complementation. The tight association of TPPP3 with TPPP1, but not with SYN, may ensure a unique mechanism for its inhibitory effect. TPPP3 or its selected fragments may become a leading agent for developing anti-Parkinson agents.

Tubulin polymerization promoting protein family member 3 (TPPP3) overexpression inhibits cell proliferation and invasion in nasopharyngeal carcinoma

The function of tubulin polymerization promoting protein family member 3 (TPPP3) in tumor cells is complicated, and the role of TPPP3 in nasopharyngeal carcinoma (NPC) remains unclear. This study aims to explore the expression of TPPP3 in NPC and its effect on NPC cells. The expression of TPPP3 in NPC tissues and other cancers were analyzed by using the Oncomine and Gene Expression Omnibus (GEO) databases. The mRNA and protein of TPPP3 were detected in NPC tissues by quantitative real-time PCR and immunohistochemistry. Furthermore, TPPP3 was overexpressed in 5-8 F and HONE1 cell lines by lentivirus transfection, and functional analysis of TPPP3 in NPC was evaluated through in vitro experiments. The expression of TPPP3 was significantly down-regulated in NPC tissues and cells. Overexpression of TPPP3 significantly inhibited proliferation of 5-8 F and HONE1 cells in vitro. In addition, overexpression of TPPP3 significantly attenuated the invasion ability of 5-8 F, HONE1 cells in vitro, but have no significant effect on migration ability. Furthermore, TPPP3 overexpression diminished the expression of MMP-2 and MMP-9 mRNA. By analyzing dataset GSE12452, it was interesting that TPPP3 high expression group mainly functioned in B cell receptor signaling pathway, cell cycle and DNA replication. In conclusion, our results suggest that TPPP3 may be considered as an antioncogene, which plays an important role in the occurrence and progression of NPC.Abbreviations: TPPP3: tubulin polymerization promoting protein family member 3; NPC: nasopharyngeal carcinoma; GEO: Gene Expression Omnibus; qRT-PCR: quantitative real-time PCR; GFP: green fluorescence protein; MOI, transfected multiplicity of infection; CCK-8: cell counting kit-8; OD: optical density; GSEA: gene set enrichment analysis; GO: Gene Ontology; KEGG: Kyoto Encyclopedia of Genes and Genomes; MMP-2: matrix metalloproteinase-2; MMP-9: matrix metalloproteinase-9.

Interaction of TPPP3 with VDAC1 Promotes Endothelial Injury through Activation of Reactive Oxygen Species

Endothelial injury plays a critical role in the pathogenesis of cardiovascular disorders and metabolic-associated vascular complications which are the leading cause of death worldwide. However, the mechanism underlying endothelial dysfunction is not completely understood. The study is aimed at investigating the role of tubulin polymerization-promoting protein family member 3 (TPPP3) in palmitic acid- (PA-) induced endothelial injury. The effect of TPPP3 on human umbilical vein endothelial cells (HUVECs) was determined by evaluating apoptosis, tube formation, and reactive oxygen species (ROS) production. TPPP3 silencing inhibited PA overload-induced apoptosis and production of ROS, along with the alteration of apoptosis-related key proteins such as BCL-2 and Bax. Mechanically, voltage-dependent anion channel 1 (VDAC1) was identified as a novel functional binding partner of TPPP3, and TPPP3 promoted VDAC1 protein stability and its activity. Further studies indicated that TPPP3 could promote apoptosis, ROS production, tube formation, and proapoptotic protein expression and reduce antiapoptotic protein expression through increasing VDAC1 expression under mildly elevated levels of PA. Collectively, these results demonstrated that TPPP3 could promote PA-induced oxidative damage in HUVECs via a VDAC1-dependent pathway, suggesting that TPPP3 might be considered as a potential therapeutic target in vascular disease.

Microtubule-Associated Proteins with Regulatory Functions by Day and Pathological Potency at Night

The sensing, integrating, and coordinating features of the eukaryotic cells are achieved by the complex ultrastructural arrays and multifarious functions of the cytoskeleton, including the microtubule network. Microtubules play crucial roles achieved by their decoration with proteins/enzymes as well as by posttranslational modifications. This review focuses on the Tubulin Polymerization Promoting Protein (TPPP/p25), a new microtubule associated protein, on its "regulatory functions by day and pathological functions at night". Physiologically, the moonlighting TPPP/p25 modulates the dynamics and stability of the microtubule network by bundling microtubules and enhancing the tubulin acetylation due to the inhibition of tubulin deacetylases. The optimal endogenous TPPP/p25 level is crucial for its physiological functions, to the differentiation of oligodendrocytes, which are the major constituents of the myelin sheath. Pathologically, TPPP/p25 forms toxic oligomers/aggregates with α-synuclein in neurons and oligodendrocytes in Parkinson's disease and Multiple System Atrophy, respectively; and their complex is a potential therapeutic drug target. TPPP/p25-derived microtubule hyperacetylation counteracts uncontrolled cell division. All these issues reveal the anti-mitotic and α-synuclein aggregation-promoting potency of TPPP/p25, consistent with the finding that Parkinson's disease patients have reduced risk for certain cancers.

High Expression of Long Noncoding RNA PCNA-AS1 Promotes Non-Small-Cell Lung Cancer Cell Proliferation and Oncogenic Activity via Upregulating CCND1

Accumulating evidences showed that aberrantly expressed long noncoding RNAs (lncRNAs) have critical roles in many cancers. However, the expression and roles of a poorly studied lncRNA PCNA-AS1 in non-small-cell lung cancer (NSCLC) remain unknown. In this study, we investigated the expression, clinical significance, biological roles, and functional mechanism of PCNA-AS1 in NSCLC. Our results showed that PCNA-AS1 was upregulated in NSCLC tissues and cell lines, and correlated with TNM stages. Functional experiments showed that overexpression of PCNA-AS1 promoted NSCLC cell proliferation and cell cycle progression. Depletion of PCNA-AS1 inhibited NSCLC cell proliferation and cell cycle progression, and also inhibited NSCLC tumor growth in vivo. Mechanistically, we found that PCNA-AS1 upregulated CCND1 expression. The expression of PCNA-AS1 was positively correlated with that of CCND1 in NSCLC tissues. Moreover, depletion of CCND1 abrogated the oncogenic roles of PCNA-AS1 in NSCLC. In conclusion, highly expressed PCNA-AS1 promotes NSCLC cell proliferation and oncogenic activity via upregulating CCND1. Our results imply that PCNA-AS1 might serve as a therapeutic target for NSCLC.

YY1 targets tubulin polymerisation-promoting protein to inhibit migration, invasion and angiogenesis in pancreatic cancer via p38/MAPK and PI3K/AKT pathways

BACKGROUND

Pancreatic cancer (PDAC) is a highly invasive cancer with poor prognosis. Recent research has found that the transcription factor Yin Yang 1 (YY1) plays an inhibitory role in the development of pancreatic cancer. It has been reported that tubulin polymerisation-promoting protein (TPPP) plays an indispensable role in a variety of tumours, but its expression and role in pancreatic cancer have not yet been elucidated.

METHODS

In this study, we performed ChIP-sequencing and found that YY1 directly binds to the promoter region of TPPP. The expression of TPPP in pancreatic cancer was detected by western blotting and immunohistochemistry. Four-week-old male BALB/c-nude mice were used to assess the effect of TPPP on pancreatic cancer.

RESULTS

Immunohistochemistry revealed that TPPP was expressed at low levels in pancreatic cancer tissues, and was associated with blood vessel invasion. The results from vivo experiments have showed that TPPP could enhance the migration and invasion of pancreatic cancer. Further experiments showed that YY1 could inhibit the migration, invasion and angiogenesis of pancreatic cancer cells by downregulating TPPP via p38/MAPK and PI3K/AKT pathways.

CONCLUSION

Our study demonstrates that TPPP may act as a promoter and may serve as a novel target for the treatment of pancreatic cancer.

Insights into Early Recovery from Influenza Pneumonia by Spatial and Temporal Quantification of Putative Lung Regenerating Cells and by Lung Proteomics

During influenza pneumonia, the alveolar epithelial cells of the lungs are targeted by the influenza virus. The distal airway stem cells (DASCs) and proliferating alveolar type II (AT2) cells are reported to be putative lung repair cells. However, their relative spatial and temporal distribution is still unknown during influenza-induced acute lung injury. Here, we investigated the distribution of these cells, and concurrently performed global proteomic analysis of the infected lungs to elucidate and link the cellular and molecular events during influenza pneumonia recovery. BALB/c mice were infected with a sub-lethal dose of influenza H1N1 virus. From 5 to 25 days post-infection (dpi), mouse lungs were subjected to histopathologic and immunofluorescence analysis to probe for global distribution of lung repair cells (using P63 and KRT5 markers for DASCs; SPC and PCNA markers for AT2 cells). At 7 and 15 dpi, infected mouse lungs were also subjected to protein mass spectrometry for relative protein quantification. DASCs appeared only in the damaged area of the lung from 7 dpi onwards, reaching a peak at 21 dpi, and persisted until 25 dpi. However, no differentiation of DASCs to AT2 cells was observed by 25 dpi. In contrast, AT2 cells began proliferating from 7 dpi to replenish their population, especially within the boundary area between damaged and undamaged areas of the infected lungs. Mass spectrometry and gene ontology analysis revealed prominent innate immune responses at 7 dpi, which shifted towards adaptive immune responses by 15 dpi. Hence, proliferating AT2 cells but not DASCs contribute to AT2 cell regeneration following transition from innate to adaptive immune responses during the early phase of recovery from influenza pneumonia up to 25 dpi.

Inhibition of TPPP3 attenuates β-catenin/NF-κB/COX-2 signaling in endometrial stromal cells and impairs decidualization

Embryo implantation and decidualization are critical events that occur during early pregnancy. Decidualization is synchronized by the crosstalk of progesterone and the cAMP signaling pathway. Previously, we confirmed the role of TPPP3 during embryo implantation in mice, but the underlying role and mechanism of TPPP3 in decidualization has not yet been understood. The current study was aimed to investigate the role of TPPP3 in decidualization in vivo and in vitro. For in vivo experiments, decidual reaction was artificially induced in the uteri of BALB/c mice. TPPP3 was found to be highly expressed during decidualization, whereas in the uteri receiving TPPP3 siRNA, decidualization was suppressed and the expression of β-catenin and decidual marker prolactin was reduced. In human endometrium, TPPP3 protein was found to be predominantly expressed in the mid-secretory phase (LH+7). In the primary culture of human endometrial stromal cells (hESCs), TPPP3 siRNA knockdown inhibited stromal-to-decidual cell transition and decreased the expression of the decidualization markers prolactin and IGFBP-1. Immunofluorescence and immunoblotting experiments revealed that TPPP3 siRNA knockdown suppressed the expression of β-catenin, NF-κB and COX-2 in hESCs during decidualization. TPPP3 inhibition also decreased NF-kB nuclear accumulation in hESCs and suppressed NF-κB transcriptional promoter activity. COX-2 expression was significantly decreased in the presence of a selective NF-kB inhibitor (QNZ) implicating that NF-kB is involved in COX-2 expression in hESCs undergoing decidualization. TUNEL assay and FACS analysis revealed that TPPP3 knockdown induced apoptosis and caused loss of mitochondrial membrane potential in hESCs. The study suggested that TPPP3 plays a significant role in decidualization and its inhibition leads to the suppression of β-catenin/NF-κB/COX-2 signaling along with the induction of mitochondria-dependent apoptosis.

Uterine TPPP3 plays important role in embryo implantation via modulation of β-catenin

Tubulin polymerization promoting protein 3 (TPPP3) is known to be expressed in the endometrium in a cyclic manner, and its functional role in the physiology of implantation remains unknown. Here we demonstrate a novel function of TPPP3 during the window of implantation and in the establishment of pregnancy using a mouse model. The increased protein expression of TPPP3 and β-catenin during peri-implantation period, i.e. D5 (receptive phase, 0800 h), was observed as compared to that on D1 (nonreceptive phase, 0800 h). SiRNATPPP3-mediated knockdown of uterine TPPP3 resulted in implantation failure and inhibited the expression of receptivity markers: LIF, Integrin-β3, IHH, and Wnt4. TPPP3 silencing in mouse endometrial epithelial cells also prevented blastocyst attachment and the adhesion reaction. In delayed implantation experiment, expression of TPPP3 was increased in active implantation group (E2 + P4) compared to delayed implantation group (P4). The increased expression of TPPP3 in E2 + P4-treated Ishikawa cells compared to vehicle or P4 or E2 alone-treated Ishikawa cells also revealed its upregulation by E2. The suppression of β-catenin in uterus under the condition of transient knockdown of TPPP3 and the co-immunoprecipitation experiment revealed that regulation of β-catenin was mediated via TPPP3 during implantation. Additionally, in order to gain insight into TPPP3 collaborators, we identified TPPP3 interacting proteins by nanoLC-MS analysis in mouse uterus which might be involved during implantation. In conclusion, our study suggests that TPPP3 is important for embryo implantation and for the establishment of early pregnancy through modulation of β-catenin.

The prognostic value of Ki67 in ovarian high-grade serous carcinoma: an 11-year cohort study of Chinese patients

OBJECTIVE

This study sought to assess the prognostic role of Ki67 in primary ovarian high-grade serous carcinoma (HGSC) and to determine whether Ki67 expression can predict responsiveness to platinum and paclitaxel chemotherapy.

RESULTS

A total of 318 women were included in the analysis and the median follow-up time was 48 months (range, 3-150 months). Ki67 proliferation indices ranged from 3% to 95% with a median of 40%. Using 40% as the cut-off value for the Ki67 index, we classified 141 patients as having low Ki67 expression and 177 patients as having high Ki67 expression. Low Ki67 expression was a predictor of platinum resistance (hazard ratio (HR) 2.85, 95% CI 1.43-5.98, P < 0.001). In the Kaplan-Meier analysis, comparisons of patients with low versus high Ki67 expression demonstrated that low Ki67 expression was significantly associated with decreased progression-free survival (PFS) (22% vs. 34% for 5-year PFS, P < 0.001) and decreased overall survival (OS) (31% vs. 55%, P < 0.001). Multivariate analysis indicated that low Ki67 expression was associated with decreased PFS (HR 2.98, 95% CI 1.75-6.56, P < 0.001) and decreased OS (HR 1.74, 95% CI 1.38-5.01, P = 0.003).

MATERIALS AND METHODS

A retrospective study of patients with stage I-IV primary ovarian HGSC was conducted from January 1, 2002, to December 31, 2012. Ki67 levels were measured via immunohistochemistry (IHC) and analyzed with respect to clinicopathological factors, and a survival analysis was performed.

CONCLUSIONS

HGSC appears to be a heterogeneous disease with different clinical outcomes. Low Ki67 expression (< 40%) in HGSC is significantly associated with platinum resistance and decreased survival.

MicroRNA-133b Negatively Regulates Zebrafish Single Mauthner-Cell Axon Regeneration through Targeting tppp3 in Vivo

Axon regeneration, fundamental to nerve repair, and functional recovery, relies on rapid changes in gene expression attributable to microRNA (miRNA) regulation. MiR-133b has been proved to play an important role in different organ regeneration in zebrafish, but its role in regulating axon regeneration in vivo is still controversial. Here, combining single-cell electroporation with a vector-based miRNA-expression system, we have modulated the expression of miR-133b in Mauthner-cells (M-cells) at the single-cell level in zebrafish. Through in vivo imaging, we show that overexpression of miR-133b inhibits axon regeneration, whereas down-regulation of miR-133b, promotes axon outgrowth. We further show that miR-133b regulates axon regeneration by directly targeting a novel regeneration-associated gene, tppp3, which belongs to Tubulin polymerization-promoting protein family. Gain or loss-of-function of tppp3 experiments indicated that tppp3 was a novel gene that could promote axon regeneration. In addition, we observed a reduction of mitochondrial motility, which have been identified to have a positive correlation with axon regeneration, in miR-133b overexpressed M-cells. Taken together, our work provides a novel way to study the role of miRNAs in individual cell and establishes a critical cell autonomous role of miR-133b in zebrafish M-cell axon regeneration. We propose that up-regulation of the newly founded regeneration-associated gene tppp3 may enhance axonal regeneration.

Knockdown of Tubulin Polymerization Promoting Protein Family Member 3 inhibits cell proliferation and invasion in human colorectal cancer

Tubulin Polymerization Promoting Protein Family Member 3 (TPPP3), a member of the TPPP protein family, has been reported to play important roles in initiation and progression of human cancers. However, the expression and underlying function of TPPP3 in colorectal cancer (CRC) have not yet been fully clarified. In this study, the mRNA and protein levels of TPPP3 in 96 clinical CRC specimens were determined by RT-PCR and immunohistochemistry. The relation between TPPP3 expression and clinicopathologic characteristics and overall survival (OS) were evaluated. Further experiments showed that knockdown of TPPP3 inhibited cell proliferation, migration and invasion and induced cell apoptosis in vitro. In addition, TPPP3 silencing resulted in a decrease of angiogenesis and S phase fraction. Thus, our results suggested that TPPP3 played an important role in CRC progress and might serve as novel therapeutic target for CRC treatment.

Role of the microtubule-associated TPPP/p25 in Parkinson's and related diseases and its therapeutic potential

INTRODUCTION

The discovery and development of therapeutic strategies for the treatments of Parkinson's disease (PD) and other synucleinopathies are limited by a lack of understanding of the pathomechanisms and their connection with different diseases such as cancers. Areas covered: The hallmarks of these diseases are frequently multifunctional disordered proteins displaying moonlighting and/or chameleon features, which are challenging drug targets. A representative of these proteins is the disordered Tubulin Polymerization Promoting Protein (TPPP/p25) expressed specifically in oligodendrocytes (OLGs) in normal brain. Its non-physiological level is tightly related to the etiology of PD and Multiple System Atrophy (TPPP/p25 enrichment in inclusions of neurons and OLGs, respectively), multiple sclerosis (TPPP/p25-positive OLG destruction), as well as glioma (loss of TPPP/p25 expression). The established anti-proliferative potency of TPPP/p25 may raise its influence in cancer development. The recognition that whereas too much TPPP/p25 could kill neurons in PD, but its loss keeps cells alive in cancer could contribute to our understanding of the interrelationship of 'TPPP/p25 diseases'. Expert commentary: The knowledge accumulated so far underlines the key roles of the multifunctional TPPP/p25 in both physiological and diverse pathological processes, consequently its validation as drug target sorely needs a new innovative strategy that is briefly reviewed here.