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

A transcriptomic and proteomic analysis and comparison of human brain tissue from patients with and without epilepsy

The present study was to investigate potential biomarkers and therapeutic targets for epilepsy by conducting a transcriptomic and proteomic analysis of human brain tissue from patients with epileptic lesions. Brain tissue was collected from the epileptic lesions after surgical resection and surgical removed brain tissue from non-epileptic patients. Using RNA sequencing and iTRAQ-based proteomic analysis, The transcriptomic analysis identified 1,604 DEGs, with 584 upregulated and 1,020 downregulated. The proteomic analysis identified 694 DEPs, with 331 upregulated and 363 downregulated. The combined transcriptomic and proteomic analysis showed that the DEGs and DEPs were mainly enriched in biological processes such as D-aspartate transport, transmembrane transport, cell junctions, vesicle transport, and metabolic processes. Tubulin polymerization promoting protein family member-3 (TPPP3), proprotein convertase subtilisin/kexin type-1 (PCSK1), and dihydropyrimidinase-like 3 (DPYSL3) were significantly altered in the epilepsy patients, and their expression trends were confirmed by the RT-qPCR, WB, and IHC staining results. By integrating transcriptomic and proteomic analyses, we identified genes and proteins expressed differently in epileptic and non-epileptic patients and their associated biological processes. Three key DEPs (TPPP3, PCSK1, and DPYSL3) were identified, indicating their potential significance in the pathological mechanisms of epilepsy.

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.

Tppp3 is a novel molecule for retinal ganglion cell identification and optic nerve regeneration

Mammalian central nervous system (CNS) axons cannot spontaneously regenerate after injury, creating an unmet need to identify molecular regulators to promote axon regeneration and reduce the lasting impact of CNS injuries. While tubulin polymerization promoting protein family member 3 (Tppp3) is known to promote axon outgrowth in amphibians, its role in mammalian axon regeneration remains unknown. Here we investigated Tppp3 in retinal ganglion cells (RGCs) neuroprotection and axonal regeneration using an optic nerve crush (ONC) model in the rodent. Single-cell RNA sequencing identified the expression of Tppp3 in RGCs of mice, macaques, and humans. Tppp3 overexpression enhanced neurite outgrowth in mouse primary RGCs in vitro, promoted axon regeneration, and improved RGC survival after ONC. Bulk RNA sequencing indicated that Tppp3 overexpression upregulates axon regeneration genes such as Bmp4 and neuroinflammatory pathways. Our findings advance regenerative medicine by developing a new therapeutic strategy for RGC neuroprotection and axon regeneration.

Accelerated cognitive aging in chronically infected HIV-1 positive individuals despite effective long-term antiretroviral therapy

People living with HIV (PLHIV) are known to be at a higher risk of developing an array of aging-related diseases despite well-adhered combined antiretroviral therapy (cART). The present study aimed to investigate the impact of chronic HIV infection on neurocognitive function in virally suppressed PLHIV. We enrolled HIV-positive individuals randomly from an ART Center in Chennai, South India. A similar number of HIV-uninfected individuals matched for age and gender with the HIV-infected individuals served as controls. All individuals provided a detailed clinical history and underwent neuropsychological assessment using the International HIV Dementia Scale (IHDS). Plasma proteome analysis was performed using the Proximity extension assay (PEA) with the Olink® neuroexploratory panel, and untargeted metabolomics was performed using Ultra-High-Performance Liquid Chromatography/Mass Spectrometry/Mass Spectrometry. Despite a median duration of 9 years on first-line cART and suppressed viremia, a significant proportion of PLHIV registered significant levels of asymptomatic neurocognitive impairment, with 71% of these individuals scoring ≤ 10 in the IHDS test. We also observed significant alterations in a number of proteins and metabolites that are known to be associated with neuroinflammation, neurodegeneration, cognitive impairment, and gastrointestinal cancers, in the PLHIV group. Thus the study provides clinical as well as laboratory evidence to substantiate the presence of asymptomatic neurocognitive impairment in a large proportion of PLHIV, despite adequate cART and undetectable viremia, thereby supporting the view that HIV infection potentiates the risk for accelerated and accentuated neurological aging. This observation highlights the need to devise and implement appropriate intervention strategies for better long term management of HIV-infected persons.

Polyphenol- and Glucuronoxylan-Rich Fiber Extract from Birch (Betula sp.) Wood Regulates Colonic Barrier Function and Cell Proliferation in Healthy Rats

Birch wood-derived fiber extracts containing glucuronoxylans (GX) and polyphenols show potential for various food technological applications. This study investigated the effect of two extracts, GXpoly and pureGX, differing in lignin content on colonic barrier function. Healthy rats were fed diets containing 10% GXpoly, pureGX, or cellulose for 4 weeks. Colon crypt depth was lower in the GX groups than in the control group, but in the proximal colon, the result was significant only in GXpoly. An artificial intelligence approach was established to measure the mucus content and goblet cells. In the distal colon, their amounts were higher in the control group than in the GX groups. All diets had a similar effect on the expression of the tight junction proteins occludin, claudin-1, and claudin-7. GXpoly enhanced the fecal IgA production. Our results suggest that GX-rich extracts could support the colonic barrier and work as functional food ingredients in the future.

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.

Transcriptome analysis of the testes of male chickens with high and low sperm motility

The reproductive performance of chicken breeders has significant economic importance in the poultry industry, and sperm motility is an indicator of reproductive performance. This study performed RNA-seq of the testes of Gushi chicken roosters with high and low sperm motility and identified differentially expressed RNAs involved in sperm motility. RNA-seq analysis showed that 73 and 67 differentially expressed mRNAs were up- and downregulated, and 47 and 56 differentially expressed long non-coding RNAs were up- and downregulated, respectively. The genes related to sperm motility and spermatogenesis included KIFC1, KCNK2, and REC8. Functional enrichment analysis revealed that the pathways related to sperm motility included oxidative phosphorylation and glycine, serine, and threonine metabolism. In addition, the MSTRG.15920.1-REC8-MSTRG.11860.2-VWC2 pathway may regulate sperm motility. This study helped elucidate the molecular genetic mechanism of sperm motility in chicken.

Telomere shortening impairs alveolar regeneration

Objectives

Short telomeres in alveolar type 2 (AT2) cells have been associated with many lung diseases. The study aimed to investigate the regeneration capacity of AT2 cells with short telomeres by knocking out Tert in mice (G4 Tert^−/−) from the whole to the cellular level.

Materials and Methods

The lung injury model of mice was established by left pneumonectomy (PNX). The proliferation and differentiation of AT2 cells were observed by immunofluorescence staining in vivo and in vitro. The difference of the gene expression between control and G4 Tert^−/− group during the regeneration of AT2 cells was compared by RNA sequencing. The expression of tubulin polymerization promoting protein 3 (TPPP3) was reduced by adeno‐associated virus delivery.

Results

The alveolar regeneration in G4 Tert^−/− mice was impaired after PNX‐induced lung injury. The regulation of cytoskeleton remodelling was defective in G4 Tert^−/− AT2 cells. The expression of TPPP3 was gradually increased during AT2 cell differentiation. The expression level of TPPP3 was reduced in G4 Tert^−/− AT2 cells. Reducing TPPP3 expression in AT2 cells limits the microtubule remodelling and differentiation of AT2 cells.

Conclusion

Short telomeres in AT2 cells result in the reduced expression level of TPPP3, leading to impaired regeneration capacity of AT2 cells.

Xenograft cancer vaccines prepared from immunodeficient mice increase tumor antigen diversity and host T cell efficiency against colorectal cancers

Autologous cancer vaccines (ACVs) are a desirable approach for personalized medicine, but the efficiency of ACVs remains unsatisfactory due to their low immunogenicity. This study developed a platform that can enhance the immunogenicity of ACVs by transplanting the tumors into immunodeficient mice. The CT26 cell line was inoculated into severe combined immunodeficient mice (SCID) for vaccine preparation where escalates tumor development, subsequently diversifying the tumor antigenic topology. CT26/SCID cancer vaccines significantly inhibited tumor growth, increased the amount of tumor infiltrating lymphocytes, and triggered Th-1 predominant immune responses. Tumor antigenic profiles of CT26/SCID cells were further analyzed by liquid chromatography-tandem mass spectrometry. Compared to CT26 parental cells, a total of 428 differentially expressed proteins (DEPs) were detected. These DEPs revealed that CT26/SCID cells overexpressed several novel therapeutic targets, including KNG1, apoA-I and, β2-GPI, which can trigger cytotoxic T cells towards Th-1 predominant immune responses and directly suppress proliferation in tumors. CT26/SCID cancer vaccines can be easily manufactured, while traits of triggering stronger antigen-specific Th-1 immune activity against tumors, are retained. Results of this study provide an effective proof-of-concept of an ACV for personalized cancer immunotherapy.

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.

TPPP3 inhibits the proliferation, invasion and migration of endometrial carcinoma targeted with miR-1827

OBJECTIVE AND DESIGN

Database screening indicated that tubulin polymerization-promoting protein 3 (TPPP3) was involved in pathogenesis of multiple cancer types. miR-1827 has a potential role in a variety of human cancers. However, the role of TPPP3 and its underlying molecular mechanism in endometrial cancer (EC) has not been investigated. Herein, we aimed to reveal the role of TPPP3/miR-1827 in EC progression.

METHODS

Tumour tissue and whole blood samples were collected for the detection of TPPP3 expression. TPPP3 shRNAs and pcDNA-TPPP3 were applied to knockdown or upregulate the TPPP3 expression, and miR-1827 mimic was used to upregulate miR-1827 level. CCK-8 and colony assays were applied to estimate the cell proliferation. Wound healing and Transwell assays were conducted to assess the cell migration and invasion abilities. The dual-luciferase reporter assay was conducted to validate the putative binding site between TPPP3 and miR-1827. Expression of TPPP3, miR-1827 and related proteins in cell lines, tissue and whole blood sample were detected using western blot, RT-qPCR and immunofluorescence.

RESULTS

TPPP3 was observed markedly elevated in EC patients and cells. TPPP3 knockdown displayed evident suppression in cell proliferation, migration and invasion in vitro and in vivo. Moreover, we identified TPPP3 as a direct and functional target gene of miR-1827 in EC cells. The miR-1827 induced regulatory effects on EC cells were partially reversed by TPPP3. Additionally, in vivo study confirmed the findings discovered in vitro.

CONCLUSION

TPPP3 exerted oncogenic roles in EC progression by sponging miR-1827. This finding might provide potential targets for EC therapy.

Requirement of splicing factor hnRNP A2B1 for tumorigenesis of melanoma stem cells

Background

Cancer stem cells play essential roles in tumorigenesis, thus forming an important target for tumor therapy. The hnRNP family proteins are important splicing factors that have been found to be associated with tumor progression. However, the influence of hnRNPs on cancer stem cells has not been extensively explored.

Methods

Quantitative real-time PCR and Western blot were used to examine gene expressions. RNA immunoprecipitation assays were conducted to identify the RNAs interacted with hnRNP A2B1. The in vivo assays were performed in nude mice.

Results

In this study, the results showed that out of 19 evaluated hnRNPs, hnRNP A2B1 was significantly upregulated in melanoma stem cells compared with non-stem cells, suggesting an important role of hnRNP A2B1 in cancer stem cells. Silencing of hnRNP A2B1 triggered cell cycle arrest in G2 phase, leading to apoptosis of melanoma stem cells. The results also revealed that hnRNP A2B1 could bind to the precursor mRNAs of pro-apoptosis genes (DAPK1, SYT7, and RNF128) and anti-apoptosis genes (EIF3H, TPPP3, and DOCK2) to regulate the splicing of these 6 genes, thus promoting the expressions of anti-apoptosis genes and suppressing the expressions of pro-apoptosis genes. The in vivo data indicated that hnRNP A2B1 was required for tumorigenesis by affecting the splicing of TPPP3, DOCK2, EIF3H, RNF128, DAPK1, and SYT7, thus suppressing apoptosis of melanoma stem cells.

Conclusion

Our findings showed the requirement of hnRNP A2B1 for tumorigenesis, thus presenting novel molecular insights into the role of hnRNPs in cancer stem cells.

TPPP3 Associated with Prognosis and Immune Infiltrates in Head and Neck Squamous Carcinoma

Tubulin polymerization promoting protein family member 3 (TPPP3) is a kind of protein that can mediate the dynamics and stability of microtubules. However, the correlations of TPPP3 between prognosis and immune infiltrates in different tumors are still unclear. The analysis of TPPP3 expression was performed via Oncomine and Gene Expression Profiling Interactive Analysis (GEPIA) website. We also used GEPIA to assess the impact of TPPPT3 on clinical outcomes. The related pathways involved in TPPP3 were analyzed by gene-set enrichment analysis (GSEA), and the correlation between TPPP3 and immune infiltration was studied by Tumor Immune Estimation Resource2.0 (TIMER 2.0). The TPPP3 expression was significantly reduced in head and neck squamous carcinoma (HNSC) compared to adjacent tissues. In addition, the low expression of TPPP3 in HNSC was significantly associated with prognosis. The pathways closely related to the low expression of TPPP3 are “Antigen Processing and Presentation,” “Primary Immunodeficiency,” and so on. The TPPP3 expression was negatively correlated with the level of CD8+ T cell, B cell, and myeloid dendritic cell infiltration in HNSC. The TPPP3 expression is closely related to multiple immunomarkers in CD8+ T cell and Myeloid dendritic cells. These data indicate that TPPP3 is associated with multiple cancers and involves multiple immune-related pathways, and TPPP3 is associated with immune infiltration levels. Besides, the TPPP3 expression may help regulate tumor-associated CD8 + T cells, DC cells in HNSC. We conclude TPPP3 can be considered as a biomarker for predicting head and neck squamous cell carcinoma prognosis and immune infiltration.

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.

Silence of TPPP3 suppresses cell proliferation, invasion and migration via inactivating NF-κB/COX2 signal pathway in breast cancer cell

Malignant phenotypes are leading causes of death in patients with breast cancer (BC). Previously, it has been proved that tubulin polymerization promoting protein 3 (TPPP3) participates in cell progressions in several human cancers. Little is known about the functions of TPPP3 in BC. Herein, we detected the expression of TPPP3 in 54 clinical BC tissues and two BC cell lines by immunohistochemistry and Western blot. CCK-8, wound healing, colony formation and Transwell assays were used to assess cell proliferation, clone formation, invasion and migration of MCF-7 and T47D cells after transfection with TPPP3 siRNA. Meanwhile, related-proteins expression was detected using Western blot. TPPP3 was found to be highly expressed in the tissues from the patients with BC. Poor outcomes were associated with the high expression of TPPP3 in all patients with BC. When MCF-7 and T47D cells receiving TPPP3 siRNA transfection, the capacities of proliferation, clone formation, invasion and migration were suppressed and the expression of MMP-2/-9 and NF-κB p65/COX2 was notably reduced. The dual-luciferase reporter assay indicated that the promoter regions of NF-κB p65 could combine to TPPP3. Overall, the present study demonstrated that TPPP3 played a significant role in BC, and its inhibition lead to the suppression of NF-κB/COX-2 signalling pathway along with the reduction of malignant phenotypes. SIGNIFICANCE OF THIS STUDY: Previously, it has been proved that tubulin polymerization promoting protein 3 (TPPP3) participates in cell progression in several human cancers. Little is known about the function of TPPP3 in BC. Our study was the first direct evidence to support the role of TPPP3 in tumorigenesis and metastasis of BC. Although the underlying mechanism has not been fully delineated, these findings suggested that TPPP3 was an important factor in the tumour progression and metastasis of BC cells and provided a molecular basis for potential therapeutic implications in the treatment of patients with BC.

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.

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.

Identification of grade and origin specific cell populations in serous epithelial ovarian cancer by single cell RNA-seq

Here we investigated different cell populations within ovarian cancer using single-cell RNA seq: fourteen samples from nine patients with differing grades (high grade, low grade and benign) as well as different origin sites (primary and metastatic tumor site, ovarian in origin and fallopian in origin). We were able to identify sixteen distinct cell populations with specific cells correlated to high grade tumors, low grade tumors, benign and one population unique to a patient with a breast cancer relapse. Furthermore the proportion of these populations changes from primary to metastatic in a shift from mainly epithelial cells to leukocytes with few cancer epithelial cells in the metastases. Differential gene expression shows myeloid lineage cells are the primary cell group expressing soluble factors in primary samples while fibroblasts do so in metastatic samples. The leukocytes that were captured did not seem to be suppressed through known pro-tumor cytokines from any of the cell populations. Single cell RNA-seq is necessary to de-tangle cellular heterogeneity for better understanding of ovarian cancer progression.