CCT6A suppresses SMAD2 and promotes prometastatic TGF-β signaling

Chaperonin containing TCP1 subunit 6A may activate Notch and Wnt pathways to facilitate the malignant behaviors and cancer stemness in oral squamous cell carcinoma

Chaperonin containing TCP1 subunit 6A (CCT6A) was recently discovered to be involved in cancer pathogenesis and stemness; however, its role in oral squamous cell carcinoma (OSCC) has not been reported. The current study aimed to investigate the impact of CCT6A on OSCC cell malignant behaviors and stemness and to explore its potentially interreacted pathways. SCC-15 and HSC-3 cells were transfected with the plasmid loading control overexpression, CCT6A overexpression, control knockout, or CCT6A knockout. Wnt4 overexpression or Notch1 overexpression plasmids were transfected into CCT6A-knockout SCC-15 cells. Cell proliferation, apoptosis, invasion, stemness, Notch, and Wnt pathways were detected in both cell lines, whereas RNA sequencing was only performed in SCC-15 cells. CCT6A was upregulated in five OSCC cell lines, including SCC-15, HSC-3, SAT, SCC-9, and KON, compared to that in the control cell line. In SCC-15 and HSC-3 cells, CCT6A overexpression increased cell proliferation, invasion, sphere formation, CD133, and Sox2 expression, but decreased cell apoptosis; on the contrary, CCT6A knockout exhibited an opposite effect on the above indexes. RNA-sequencing data revealed that the Wnt and Notch pathways were involved in the CCT6A'effect on SCC-15 cell functions. CCT6A positively regulates the Wnt and Notch pathways in SCC-15 and HSC-3 cells. Importantly, it was shown that activation of the Wnt or Notch pathways attenuated the effect of CCT6A knockout on SCC-15 cell survival, invasion, and stemness. CCT6A may promote OSCC malignant behavior and stemness by activating the Wnt and Notch pathways.

Multi-omic profiling reveals potential biomarkers of hepatocellular carcinoma prognosis and therapy response among mitochondria-associated cell death genes in the context of 3P medicine

Background

Cancer cell growth, metastasis, and drug resistance are major challenges in treating liver hepatocellular carcinoma (LIHC). However, the lack of comprehensive and reliable models hamper the effectiveness of the predictive, preventive, and personalized medicine (PPPM/3PM) strategy in managing LIHC.

Methods

Leveraging seven distinct patterns of mitochondrial cell death (MCD), we conducted a multi-omic screening of MCD-related genes. A novel machine learning framework was developed, integrating 10 machine learning algorithms with 67 different combinations to establish a consensus mitochondrial cell death index (MCDI). This index underwent rigorous evaluation across training, validation, and in-house clinical cohorts. A comprehensive multi-omics analysis encompassing bulk, single-cell, and spatial transcriptomics was employed to achieve a deeper insight into the constructed signature. The response of risk subgroups to immunotherapy and targeted therapy was evaluated and validated. RT-qPCR, western blotting, and immunohistochemical staining were utilized for findings validation.

Results

Nine critical differentially expressed MCD-related genes were identified in LIHC. A consensus MCDI was constructed based on a 67-combination machine learning computational framework, demonstrating outstanding performance in predicting prognosis and clinical translation. MCDI correlated with immune infiltration, Tumor Immune Dysfunction and Exclusion (TIDE) score and sorafenib sensitivity. Findings were validated experimentally. Moreover, we identified PAK1IP1 as the most important gene for predicting LIHC prognosis and validated its potential as an indicator of prognosis and sorafenib response in our in-house clinical cohorts.

Conclusion

This study developed a novel predictive model for LIHC, namely MCDI. Incorporating MCDI into the PPPM framework will enhance clinical decision-making processes and optimize individualized treatment strategies for LIHC patients.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13167-024-00362-8.

Receptor-activated transcription factors and beyond: multiple modes of Smad2/3-dependent transmission of TGF-β signaling

Transforming growth factor β (TGF-β) is a pleiotropic cytokine that is widely distributed throughout the body. Its receptor proteins, TGF-β type I and type II receptors, are also ubiquitously expressed. Therefore, the regulation of various signaling outputs in a context-dependent manner is a critical issue in this field. Smad proteins were originally identified as signal-activated transcription factors similar to signal transducer and activator of transcription proteins. Smads are activated by serine phosphorylation mediated by intrinsic receptor dual specificity kinases of the TGF-β family, indicating that Smads are receptor-restricted effector molecules downstream of ligands of the TGF-β family. Smad proteins have other functions in addition to transcriptional regulation, including post-transcriptional regulation of micro-RNA processing, pre-mRNA splicing, and m6A methylation. Recent technical advances have identified a novel landscape of Smad-dependent signal transduction, including regulation of mitochondrial function without involving regulation of gene expression. Therefore, Smad proteins are receptor-activated transcription factors and also act as intracellular signaling modulators with multiple modes of function. In this review, we discuss the role of Smad proteins as receptor-activated transcription factors and beyond. We also describe the functional differences between Smad2 and Smad3, two receptor-activated Smad proteins downstream of TGF-β, activin, myostatin, growth and differentiation factor (GDF) 11, and Nodal.

LINC02454-CCT complex interaction is essential for telomerase activity and cell proliferation in head and neck squamous cell carcinoma

Telomerase activity is upregulated in head and neck squamous cell carcinoma (HNSCC), yet its regulatory mechanisms remain unclear. Here, we identified a cancer-specific lncRNA (LINC02454) associated with poor prognosis by using LncRNA chip of our HNSCC cohorts and external datasets. Through employing negative-stain transmission electron microscopy (NS-TEM), we discovered an interaction between LINC02454 and CCT complex which would augment telomerase activity for maintaining telomere homeostasis. Supporting this, in the telomerase repeat amplification protocol (TRAP) assay and quantitative fluorescence in situ hybridization (Q-FISH) analysis, LINC02454 depletion significantly reduced telomerase activity and shortened telomere length. Consistently, pathways related to telomerase, mitosis, and apoptosis were significantly impacted upon LINC02454 knockdown in RNAseq analysis. Functionally, LINC02454-deficient cells exhibited a more significant senescence phenotype in β-galactosidase staining, cell cycle, and apoptosis assays. We further confirmed the role of LINC02454 in HNSCC proliferation through a combination of in vitro and in vivo experiments. The therapeutic potential of targeting LINC02454 was verified by adenovirus-shRNA approach in HNSCC patient-derived xenograft (PDX) models. In summary, our findings provided valuable insights into the molecular mechanisms of HNSCC tumorigenesis and potential targets for future treatment modalities.

Revisiting the chaperonin T-complex protein-1 ring complex in human health and disease: A proteostasis modulator and beyond

BACKGROUND

Disrupted protein homeostasis (proteostasis) has been demonstrated to facilitate the progression of various diseases. The cytosolic T-complex protein-1 ring complex (TRiC/CCT) was discovered to be a critical player in orchestrating proteostasis by folding eukaryotic proteins, guiding intracellular localisation and suppressing protein aggregation. Intensive investigations of TRiC/CCT in different fields have improved the understanding of its role and molecular mechanism in multiple physiological and pathological processes.

MAIN BODY

In this review, we embark on a journey through the dynamic protein folding cycle of TRiC/CCT, unraveling the intricate mechanisms of its substrate selection, recognition, and intriguing folding and assembly processes. In addition to discussing the critical role of TRiC/CCT in maintaining proteostasis, we detail its involvement in cell cycle regulation, apoptosis, autophagy, metabolic control, adaptive immunity and signal transduction processes. Furthermore, we meticulously catalogue a compendium of TRiC-associated diseases, such as neuropathies, cardiovascular diseases and various malignancies. Specifically, we report the roles and molecular mechanisms of TRiC/CCT in regulating cancer formation and progression. Finally, we discuss unresolved issues in TRiC/CCT research, highlighting the efforts required for translation to clinical applications, such as diagnosis and treatment.

CONCLUSION

This review aims to provide a comprehensive view of TRiC/CCT for researchers to inspire further investigations and explorations of potential translational possibilities.

CCT6A dysregulation in surgical prostate cancer patients: association with disease features, treatment information, and prognosis

OBJECTIVE

Chaperonin-containing tailless complex polypeptide 1 subunit 6A (CCT6A) involves several solid cancers' development and progression, while its clinical utility in prostate cancer management is rarely revealed. Consequently, the present study intended to investigate the linkage of CCT6A with disease features, treatment information, and prognosis of surgical prostate cancer patients.

METHODS

CCT6A in 220 surgical prostate cancer patients was determined via immunohistochemistry. Additionally, survival analyses on data from the public databases were performed to validate the prognostic value of CCT6A further.

RESULTS

CCT6A expression was upregulated in tumor tissue than in adjacent tissue (P < 0.001). Increased CCT6A was related to elevated Gleason score (P < 0.001) and pathological T stage (P = 0.029). CCT6A was increased in patients with positive surgical margin status (vs. negative) (P = 0.029) and patients with adjuvant external-beam radiation therapy (vs. no) (P = 0.001). Concerning the prognostic value, high tumor CCT6A was linked with shortened disease-free survival (DFS) (P = 0.009), which was also validated through further Cox's proportional hazard regression model analyses (hazard ratio: 2.695, 95% CI: 1.086-6.683, P = 0.032), whereas CCT6A was not correlated with overall survival (OS) (P > 0.050). Additionally, the Gene Expression Profiling Interactive Analysis database indicated that high tumor CCT6A was related to shortened DFS (P = 0.036), but it was not associated with OS (P > 0.050); meanwhile, the Human Protein Atlas database suggested that high tumor CCT6A was linked with reduced OS (P = 0.048).

CONCLUSION

Tumor CCT6A high expression correlates with the elevated Gleason score, pathological T stage, and shortened DFS in surgical prostate cancer patients.

An E3 ubiquitin-proteasome gene signature for predicting prognosis in patients with pancreatic cancer

Pancreatic cancer is the seventh leading cause of cancer death worldwide, which is demonstrated with remarkable resistance to radiotherapy and chemotherapy. The identification of prognosis signature and novel prognostic markers will facilitate patient stratification and an individualized precision therapy strategy. In this study, TCGA-PAAD was used to screen prognostic E3 ubiquitin ligases and establish prognostic signatures, and GEO database was used to verify the accuracy of prognostic signatures. Functional analysis, in vitro experiments and clinical cohort studies were used to analyze the function and prognostic efficacy of the target gene. An E3 ligase-based signature of 9 genes and the nomogram were developed, and the signature was proved to accurately predict the prognosis of patients with pancreatic cancer. WDR37 might be the most prognostic E3 ubiquitin ligase in pancreatic cancer, and the clinical cohort analyses suggested a tumor-suppressive role. The results of functional analysis and in vitro experiments indicated that WDR37 may promote the degradation of TCP1 complex to inhibit tumor and improve immune cell infiltration. The E3 ligase-based signature accurately predicted the prognosis of patients with pancreatic cancer, so it can be used as a decision-making tool to guide the treatment of patients with pancreatic cancer. At the same time, WDR37, the main gene in E3PMP signature, can be used as the most prognostic E3 ubiquitin ligase in the treatment of pancreatic cancer.

CCT6A promotes esophageal squamous cell carcinoma cell proliferation, invasion and epithelial-mesenchymal transition by activating TGF-β/Smad/c-Myc pathway

OBJECTIVE

Chaperonin-containing TCP1 subunit 6A (CCT6A) facilitates several malignant cancer behaviors, but its regulation of esophageal squamous cell carcinoma (ESCC) has not been reported. This study aimed to investigate the effect of CCT6A on cell proliferation, apoptosis, invasion and epithelial-mesenchymal transition (EMT) and its interaction with the TGF-β/Smad/c-Myc pathway in ESCC.

METHODS

CCT6A expression was detected in ESCC and normal esophageal epithelial cell lines by RT‒qPCR and western blotting. Furthermore, CCT6A siRNA, negative control (NC) siRNA, CCT6A encoding plasmid and NC encoding plasmid were transfected into OE21 and TE-1 cells. Subsequently, CCT6A siRNA- and NC siRNA-transfected cells were treated with TGF-β for rescue experiments. Cell proliferation, apoptosis, invasion, and E-cadherin/N-cadherin and p-Smad2/p-Smad3/c-Myc expression were detected.

RESULTS

CCT6A expression was increased in KYSE-180, TE-1, TE-4 and OE21 cells compared with HET-1A cells. In both OE21 and TE-1 cells, CCT6A knockdown inhibited cell proliferation, invasion and N-cadherin expression while promoting cell apoptosis and E-cadherin expression; meanwhile, CCT6A overexpression had the opposite effects. Furthermore, in both OE21 and TE-1 cells, CCT6A knockdown decreased p-Smad2/Smad2, p-Smad3/Smad3 and c-Myc/GAPDH expression; CCT6A overexpression had the opposite effects. Next, TGF-β facilitated cell proliferation, invasion, and N-cadherin, p-Smad2/Smad2, p-Smad3/Smad2 and c-Myc/GAPDH expression while repressing cell apoptosis and E-cadherin expression in OE21 and TE-1 cells; importantly, TGF-β could compensate for the regulation of CCT6A knockdown on these activities.

CONCLUSION

CCT6A facilitates ESCC malignant activities by activating the TGF-β/Smad/c-Myc pathway, which sheds light on the identification of a possible therapeutic target in the management of ESCC.

Construction of a prognostic model for lung adenocarcinoma based on heat shock protein-related genes and immune analysis

Lung adenocarcinoma (LUAD) represents a prevalent form of cancer, with low early diagnosis rates and high mortality rates, posing a global health challenge. Heat shock proteins (HSPs) assume a crucial role within the tumor immune microenvironment (TME) of LUAD. Here, a collection of 97 HSP-related genes (HSPGs) was assembled based on prior literature reports, of which 36 HSPGs were differentially expressed in LUAD. In The Cancer Genome Atlas (TCGA) cohort, we constructed a prognostic model for risk stratification and prognosis prediction by integrating 13 HSPGs. In addition, the prognostic significance and predictive efficacy of the HSP-related riskscore were examined and validated in the Gene Expression Omnibus (GEO) cohort. To facilitate the clinical use of this riskscore, we also established a nomogram scale by verifying its effectiveness through different methods. In light of these outcomes, we concluded a significant correlation between HSPs and TME in LUAD, and the riskscore can be a reliable prognostic indicator. Furthermore, this study evaluated the differences in immunophenoscore, tumor immune dysfunction and exclusion score, and sensitivity to several common chemotherapy drugs among LUAD individuals in different risk groups, which may aid in clinical decision-making for immune therapy and chemotherapy in LUAD individuals.

A potential tumor marker: Chaperonin containing TCP‑1 controls the development of malignant tumors (Review)

Due to concealment, high invasiveness and a lack of indicators, malignant tumors have emerged as one of the deadliest diseases worldwide and their incidence is rising yearly. Research has revealed that the chaperonin family member, chaperonin containing TCP‑1 (CCT), serves a crucial role in malignant tumors. CCT is involved in the growth of numerous malignant tumors such as lung cancer, breast cancer, hepatocellular carcinoma and colorectal cancer and assists the folding of a number of proteins linked to cancer, such as KRAS, p53 and STAT3. According to clinical data, CCT is highly expressed in a range of tumor cells and is associated with poor patient prognosis. In addition, through controlling the cell cycle or interacting with other proteins (including YAP1, HoXB2 and SMAD2), CCT has an effect on the proliferation, invasion and migration of cancer cells. As a result, it is possible that CCT will become a new tumor marker or therapeutic target, which will provide some guidance for early tumor screening or late tumor prognosis. In the present review, the molecular properties of CCT are introduced, alongside a summary of its interactions with other cancer‑related proteins and a discussion of its function in common malignant tumors. It is expected that the present review will offer fresh approaches to the treatment of cancer.

A Treg-specific long noncoding RNA maintains immune-metabolic homeostasis in aging liver

Regulatory T (Treg) cells modulate several aging-related liver diseases. However, the molecular mechanisms regulating Treg function in this context are unknown. Here we identified a long noncoding RNA, Altre (aging liver Treg-expressed non-protein-coding RNA), which was specifically expressed in the nucleus of Treg cells and increased with aging. Treg-specific deletion of Altre did not affect Treg homeostasis and function in young mice but caused Treg metabolic dysfunction, inflammatory liver microenvironment, liver fibrosis and liver cancer in aged mice. Depletion of Altre reduced Treg mitochondrial integrity and respiratory capacity, and induced reactive oxygen species accumulation, thus increasing intrahepatic Treg apoptosis in aged mice. Moreover, lipidomic analysis identified a specific lipid species driving Treg aging and apoptosis in the aging liver microenvironment. Mechanistically, Altre interacts with Yin Yang 1 to orchestrate its occupation on chromatin, thereby regulating the expression of a group of mitochondrial genes, and maintaining optimal mitochondrial function and Treg fitness in the liver of aged mice. In conclusion, the Treg-specific nuclear long noncoding RNA Altre maintains the immune-metabolic homeostasis of the aged liver through Yin Yang 1-regulated optimal mitochondrial function and the Treg-sustained liver immune microenvironment. Thus, Altre is a potential therapeutic target for the treatment of liver diseases affecting older adults.

Interaction of C/EBPβ with SMAD2 and SMAD4 genes induces the formation of lipid droplets in bovine myoblasts

As a key component of Transforming growth factor-β (TGF-β) pathway, Smad2 has many crucial roles in a variety of cellular processes, but it cannot bind DNA without complex formation with Smad4. In the present study, the molecular mechanism in the progress of myogenesis underlying transcriptional regulation of SMAD2 and SMAD4 had been clarified. The result showed the inhibition between SMAD2 and SMAD4, which promotes and inhibits bovine myoblast differentiation, respectively. Further, the characterization of promoter region of SMAD2 and SMAD4 was analyzed, and identified C/EBPβ directly bound to the core region of both SMAD2 and SMAD4 genes promoter and stimulated the transcriptional activity. However, C/EBPβ has lower expression in myoblasts which plays vital function in the transcriptional networks controlling adipogenesis, while the overexpression of C/EBPβ gene in myoblasts significantly increased SMAD2 and SMAD4 gene expression, induced the formation of lipid droplet in bovine myoblasts, and promoted the expression of adipogenesis-specific genes. Collectively, our results showed that C/EBPβ may play an important role in the trans-differentiation and dynamic equilibrium of myoblasts into adipocyte cells via promoting an increase in SMAD2 and SMAD4 gene levels. These results will provide an important basis for further understanding of the TGFβ pathway and C/EBPβ gene during myogenic differentiation.

Immunostaining of βA-Activin and Follistatin Is Decreased in HPV(+) Cervical Pre-Neoplastic and Neoplastic Lesions

The activin-follistatin system regulates several cellular processes, including differentiation and tumorigenesis. We hypothesized that the immunostaining of βA-activin and follistatin varies in neoplastic cervical lesions. Cervical paraffin-embedded tissues from 162 patients sorted in control (n = 15), cervical intraepithelial neoplasia (CIN) grade 1 (n = 38), CIN2 (n = 37), CIN3 (n = 39), and squamous cell carcinoma (SCC; n = 33) groups were examined for βA-activin and follistatin immunostaining. Human papillomavirus (HPV) detection and genotyping were performed by PCR and immunohistochemistry. Sixteen samples were inconclusive for HPV detection. In total, 93% of the specimens exhibited HPV positivity, which increased with patient age. The most detected high-risk (HR)-HPV type was HPV16 (41.2%) followed by HPV18 (16%). The immunostaining of cytoplasmatic βA-activin and follistatin was higher than nuclear immunostaining in all cervical epithelium layers of the CIN1, CIN2, CIN3, and SCC groups. A significant decrease (p < 0.05) in the cytoplasmic and nuclear immunostaining of βA-activin was detected in all cervical epithelial layers from the control to the CIN1, CIN2, CIN3, and SCC groups. Only nuclear follistatin immunostaining exhibited a significant reduction (p < 0.05) in specific epithelial layers of cervical tissues from CIN1, CIN2, CIN3, and SCC compared to the control. Decreased immunostaining of cervical βA-activin and follistatin at specific stages of CIN progression suggests that the activin-follistatin system participates in the loss of the differentiation control of pre-neoplastic and neoplastic cervical specimens predominantly positive for HPV.

PHF14 enhances DNA methylation of SMAD7 gene to promote TGF-β-driven lung adenocarcinoma metastasis

Aberrant activation of TGF-β signaling plays a pivotal role in cancer metastasis and progression. However, molecular mechanisms underlying the dysregulation of TGF-β pathway remain to be understood. Here, we found that SMAD7, a direct downstream transcriptional target and also a key antagonist of TGF-β signaling, is transcriptionally suppressed in lung adenocarcinoma (LAD) due to DNA hypermethylation. We further identified that PHF14 binds DNMT3B and serves as a DNA CpG motif reader, recruiting DNMT3B to the SMAD7 gene locus, resulting in DNA methylation and transcriptional suppression of SMAD7. Our in vitro and in vivo experiments showed that PHF14 promotes metastasis through binding DNMT3B to suppress SMAD7 expression. Moreover, our data revealed that PHF14 expression correlates with lowered SMAD7 level and shorter survival of LAD patients, and importantly that SMAD7 methylation level of circulating tumor DNA (ctDNA) can potentially be used for prognosis prediction. Together, our present study illustrates a new epigenetic mechanism, mediated by PHF14 and DNMT3B, in the regulation of SMAD7 transcription and TGF-β-driven LAD metastasis, and suggests potential opportunities for LAD prognosis.

ATOH8 binds SMAD3 to induce cellular senescence and prevent Ras-driven malignant transformation

The process of oncogene-induced senescence (OIS) and the conversion between OIS and malignant transformation during carcinogenesis is poorly understood. Here, we show that following overactivation of oncogene Ras in lung epithelial cells, high-level transforming growth factor β1 (TGF-β1)-activated SMAD3, but not SMAD2 or SMAD4, plays a determinant role in inducing cellular senescence independent of the p53/p16/p15 senescence pathways. Importantly, SMAD3 binds a potential tumor suppressor ATOH8 to form a transcriptional complex that directly represses a series of cell cycle-promoting genes and consequently causes senescence in lung epithelial cells. Interestingly, the prosenescent SMAD3 converts to being oncogenic and essentially facilitates oncogenic Ras-driven malignant transformation. Furthermore, depleting Atoh8 rapidly accelerates oncogenic Ras-driven lung tumorigenesis, and lung cancers driven by mutant Ras and Atoh8 loss, but not by mutant Ras only, are sensitive to treatment of a specific SMAD3 inhibitor. Moreover, hypermethylation of the ATOH8 gene can be found in approximately 12% of clinical lung cancer cases. Together, our findings demonstrate not only epithelial cellular senescence directed by a potential tumor suppressor-controlled transcriptional program but also an important interplay between the prosenescent and transforming effects of TGF-β/SMAD3, potentially laying a foundation for developing early detection and anticancer strategies.

CCT6A knockdown suppresses osteosarcoma cell growth and Akt pathway activation in vitro

We assessed the role of the protein-coding gene chaperonin-containing TCP1 subunit 6A (CCT6A) in osteosarcoma, as this is currently unknown. Using data from the R2 online genomic analysis and visualization application, we found that CCT6A messenger ribonucleic acid (RNA) expression is increased in osteosarcoma tissue and cells. Transfection of CCT6A small interfering RNA into cultured osteosarcoma cells revealed that CCT6A knockdown attenuates cell growth, cell viability, cell survival, and induced apoptosis and cell cycle progression at the G0/G1 phases. Moreover, CCT6A knockdown downregulated phospho-protein kinase B (p-Akt), cyclinD1 and B-cell lymphoma-2, whereas upregulated Bcl-2-associated X-protein expression. Thus, CCT6A knockdown inhibits cell proliferation, induces cell apoptosis, and suppresses the Akt pathway.

Identification of Cuproptosis-Related Subtypes in Lung Cancer, Characterization of Tumor Microenvironment Infiltration, and Establishment of a Prognostic Model

Cuproptosis, a recently found kind of programmed cell death, has been linked to tumor development, prognosis, and therapeutic response. The roles of cuproptosis-related genes (CRG) in the tumor microenvironment (TME) are, nevertheless, unknown. We evaluated alterations in CRG and assessed the related expression patterns in 1445 lung cancer (LC) samples from three separate datasets, analyzing genetic, and transcriptional domains. We discovered two separate molecular subtypes of CRG and discovered that various subtypes of CRG were connected with patient clinical features and prognosis. Furthermore, we discovered connections between distinct CRG subtypes and TME cell infiltration features. The CRG_score was then developed and validated for predicting overall survival (OS). Following that, we investigated the relationship between CRG_score and the cancer stem cell (CSC) index and chemotherapeutic treatment sensitivity. In addition, we created a very accurate nomogram to increase the clinical usefulness of CRG_score. The potential roles of CRG in the tumor-immune-microenvironment, clinical characteristics, and prognosis in LC are demonstrated by our multiplex study. These findings expand our understanding of CRG in LC and may open up new options for assessing LC patients' prognosis and generating more effective immunotherapeutic treatments.

Smad2Δexon3 and Smad3 have distinct properties in signal transmission leading to TGF-β-induced cell motility

In mammalian cells, Smad2 and Smad3, two receptor-regulated Smad proteins, play crucial roles in the signal transmission of transforming growth factor-β (TGF-β) and are involved in various cell regulatory processes, including epithelial-mesenchymal transition-associated cell responses, that is, cell morphological changes, E-cadherin downregulation, stress fiber formation, and cell motility enhancement. Smad2 contains an additional exon encoding 30 amino acid residues compared with Smad3, leading to distinct Smad2 and Smad3 functional properties. Intriguingly, Smad2 also has an alternatively spliced isoform termed Smad2Δexon3 (also known as Smad2β) lacking the additional exon and behaving similarly to Smad3. However, Smad2Δexon3 and Smad3 signaling properties have not yet been compared in detail. In this study, we reveal that Smad2Δexon3 rescues multiple TGF-β-induced in vitro cellular responses that would become defective upon SMAD3 KO but does not rescue cell motility enhancement. Using Smad2Δexon3/Smad3 chimeric proteins, we identified that residues Arg-104 and Asn-210 in Smad3, which are not conserved in Smad2Δexon3, are key for TGF-β-enhanced cell motility. Moreover, we discovered that Smad2Δexon3 fails to rescue the enhanced cell motility as it does not mediate TGF-β signals to downregulate transcription of ARHGAP24, a GTPase-activating protein that targets Rac1. This study reports for the first time distinct signaling properties of Smad2Δexon3 and Smad3.

Knockdown of RhoQ, a member of Rho GTPase, accelerates TGF-β-induced EMT in human lung adenocarcinoma

Lung cancer is the leading cause of cancer-related deaths worldwide, and the most common subtype of lung cancer is adenocarcinoma. RhoQ is a Rho family GTPase with primary sequence and structural similarities to Cdc42 and RhoJ. RhoQ is involved in neurite outgrowth via membrane trafficking and is essential for insulin-stimulated glucose uptake in mature adipocytes. However, the function of RhoQ in lung adenocarcinoma (LUAD) remains unclear. In this study, RhoQ siRNAs were introduced into A549 and PC-9 cells. Expression level of EMT-related genes and invasion ability were investigated using Western blot and transwell assay. To examine the relationship between RhoQ expression and prognosis of LUAD, Kaplan–Meier plotter was used. We discovered that suppressing RhoQ expression promoted TGF-β-mediated EMT and invasion in LUAD cell lines. Furthermore, RhoQ knockdown increased Smad3 phosphorylation and Snail expression, indicating that RhoQ was involved in TGF/Smad signaling during the EMT process. Moreover, Kaplan–Meier plotter analysis revealed that low RhoQ levels were associated with poor overall survival in patients with LUAD. In conclusion, these findings shed light on RhoQ's role as a negative regulator of TGF-β-mediated EMT in LUAD.

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Knockdown of RhoQ expression promoted TGF-β-mediated EMT and invasion in human lung adenocarcinoma cells.

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RhoQ knockdown increased Smad3 phosphorylation and Snail expression during the EMT process.

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Low RhoQ levels were associated with poor overall survival in patients with lung adenocarcinoma.

The intercorrelation among CCT6A, CDC20, CCNB1, and PLK1 expressions and their clinical value in papillary thyroid carcinoma prognostication

BACKGROUND

CCT6A promotes several carcinomas' growth and invasion in multiple ways, and it relates to CCNB1 and PLK1 through its interaction with CDC20 via protein-protein interaction bioinformatics. This study aimed to explore the intercorrelation among CCT6A, CDC20, CCNB1, and PLK1, and their association with tumor features and prognosis in papillary thyroid carcinoma (PTC) patients.

METHODS

CCT6A, CDC20, CCNB1, and PLK1 expressions in 186 tumor and 30 non-tumor specimens from PTC patients were determined by immunohistochemical (IHC). Clinical features, disease-free survival (DFS), and overall survival (OS) were retrieved.

RESULTS

CCT6A, CDC20, CCNB1, and PLK1 expressions were upregulated in tumor tissues compared with non-tumor tissues (all p < 0.001). CCT6A expression positively correlated with CDC20, CCNB1, and PLK1 expressions; besides, CDC20 expression positively associated with CCNB1 and PLK1 expressions, and CCNB1 expression was also positively related to PLK1 expression (all p < 0.05). Moreover, elevated tumor CCT6A expression was correlated with extrathyroidal invasion (p = 0.015), higher pT stage (p < 0.001), pN stage (p = 0.046), and pTNM stage (p = 0.042); while tumor CDC20, CCNB1, and PLK1 expressions only correlated with some of these indexes (most p < 0.05). Notably, CCT6A and CDC20 high expressions predicted worse DFS and OS (all p < 0.05); CCNB1 positive expression only predicted poor DFS (p = 0.044) but not OS (p = 0.152); however, PLK1 expression failed to predict these two indexes (both p > 0.05). After adjustment using multivariate Cox's regression, CCT6A expression (high vs. low) independently estimated shorter DFS (p = 0.010) and OS (p = 0.006).

CONCLUSION

CCT6A, CDC20, CCNB1, and PLK1 are intercorrelated, and they exhibit certain prognostic values in PTC patients.

Chaperonin-containing tailless complex polypeptide 1 subunit 6A links with aggravating tumor features and disease-free survival in surgical gastric cancer patients: A long-term follow-up study

BACKGROUND

Chaperonin-containing tailless complex polypeptide 1 subunit 6A (CCT6A) promotes several gastrointestinal-cancer malignant behaviors, while its clinical value in surgical gastric cancer is not clear. Hence, we aimed to investigate this issue.

METHODS

Totally, tumor and adjacent specimens from 262 surgical gastric cancer patients were collected for measuring CCT6A protein level by immunohistochemistry (IHC) staining; meanwhile, specimens from 109 patients were used for evaluating CCT6A mRNA expression by reverse transcription-quantitative polymerase chain reaction (RT-qPCR).

RESULTS

CCT6A IHC score and CCT6A mRNA expression were upregulated in the tumor tissue compared with the adjacent tissue (both P<0.001). Besides, elevated CCT6A IHC score was correlated with larger tumor size (P<0.001), advanced T stage (P=0.001), N stage (P=0.003) and tumor node metastasis (TNM) stage (P=0.001). Meanwhile, increased CCT6A mRNA expression was associated with higher T stage (P=0.008) and TNM stage (P=0.020). Besides, CCT6A protein high (P=0.017) and CCT6A mRNA high (P=0.047) were correlated with unfavorable disease-free survival (DFS), whereas neither CCT6A protein nor CCT6A mRNA expression was related to the overall survival (OS) (both P>0.05). Additionally, the multivariable Cox's proportional hazards regression analysis revealed that CCT6A protein high was independently correlated with shorter DFS (adjusted hazard ratio (HR): 2.032, P=0.005), but not with OS.

CONCLUSION

CCT6A is upregulated with its overexpression linking with advanced T stage, TNM stage and unfavorable DFS in surgical gastric cancer patients.

CCT6A and CHCHD2 Are Coamplified with EGFR and Associated with the Unfavorable Clinical Outcomes of Lung Adenocarcinoma

Chaperonin containing TCP1 subunit 6A (CCT6A) and coiled-coil-helix-coiled-coil-helix domain containing 2 (CHCHD2) are located at the chromosome 7p11 region proximal to epidermal growth factor receptor (EGFR). However, the amplifications, expressions, and the prognostic effects of CCT6A and CHCDH2 in lung adenocarcinoma (LUAD) are unclear. Here, using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets, we found that CCT6A was coamplified and coexpressed with EGFR in LUAD patients. CCT6A amplification was correlated with the unfavorable outcomes of LUAD. Moreover, CCT6A was upregulated in LUAD tissues, and CCT6A overexpression was correlated with the unfavorable relapse free survival or overall survival of LUAD. On the contrary, CCT6A was hypomethylated in LUAD, and CCT6A hypermethylation was correlated with the favorable overall survival of LUAD. Similar expression and methylation profiling of CCT6A were obtained in 479 lung normal tissues and 544 LUAD tissues collected from 11 independent datasets. In 1,462 LUAD patients from eight independent cohorts, CCT6A was also correlated with LUAD relapse-free survival or overall survival. Furthermore, CCT6A overexpression promoted the cell growth and invasion of LUAD. Identification of genes differentially expressed in CCT6A highly expressed LUAD patients revealed that CHCHD2 was the most correlated with CCT6A expression. CHCHD2 was coamplified with CCT6A. CHCHD2 was upregulated in LUAD tissues, and overexpression of CHCHD2 was correlated with the shorted relapse-free survival or overall survival of LUAD. Overall, our results revealed that CCT6A and CHCHD2 were coamplifying and coexpressing with EGFR and were correlated with the unfavorable clinical outcomes of LUAD.

Long noncoding RNA Smyca coactivates TGF-β/Smad and Myc pathways to drive tumor progression

Background

Metastasis and chemoresistance are major culprits of cancer mortality, but factors contributing to these processes are incompletely understood.

Methods

Bioinformatics methods were used to identify the relations of Smyca expression to clinicopathological features of human cancers. RNA-sequencing analysis was used to reveal Smyca-regulated transcriptome. RNA pull-down and RNA immunoprecipitation were used to examine the binding of Smyca to Smad3/4 and c-Myc/Max. Chromatin immunoprecipitation and chromatin isolation by RNA purification were used to determine the binding of transcription factors and Smyca to various gene loci, respectively. Real-time RT-PCR and luciferase assay were used to examine gene expression levels and promoter activities, respectively. Xenograft mouse models were performed to evaluate the effects of Smyca on metastasis and chemoresistance. Nanoparticle-assisted gapmer antisense oligonucleotides delivery was used to target Smyca in vivo.

Results

We identify lncRNA Smyca for its association with poor prognosis of many cancer types. Smyca potentiates metabolic reprogramming, migration, invasion, cancer stemness, metastasis and chemoresistance. Mechanistically, Smyca enhances TGF-β/Smad signaling by acting as a scaffold for promoting Smad3/Smad4 association and further serves as a Smad target to amplify/prolong TGF-β signaling. Additionally, Smyca potentiates c-Myc-mediated transcription by enhancing the recruitment of c-Myc/Max complex to a set of target promoters and c-Myc binding to TRRAP. Through potentiating TGF-β and c-Myc pathways, Smyca synergizes the Warburg effect elicited by both pathways but evades the anti-proliferative effect of TGF-β. Targeting Smyca prevents metastasis and overcomes chemoresistance.

Conclusions

This study uncovers a lncRNA that coordinates tumor-relevant pathways to orchestra a pro-tumor program and establishes the clinical values of Smyca in cancer prognosis and therapy.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13045-022-01306-3.

The TRiCky Business of Protein Folding in Health and Disease

Maintenance of the cellular proteome or proteostasis is an essential process that when deregulated leads to diseases like neurological disorders and cancer. Central to proteostasis are the molecular chaperones that fold proteins into functional 3-dimensional (3D) shapes and prevent protein aggregation. Chaperonins, a family of chaperones found in all lineages of organisms, are efficient machines that fold proteins within central cavities. The eukaryotic Chaperonin Containing TCP1 (CCT), also known as Tailless complex polypeptide 1 (TCP-1) Ring Complex (TRiC), is a multi-subunit molecular complex that folds the obligate substrates, actin, and tubulin. But more than folding cytoskeletal proteins, CCT differs from most chaperones in its ability to fold proteins larger than its central folding chamber and in a sequential manner that enables it to tackle proteins with complex topologies or very large proteins and complexes. Unique features of CCT include an asymmetry of charges and ATP affinities across the eight subunits that form the hetero-oligomeric complex. Variable substrate binding capacities endow CCT with a plasticity that developed as the chaperonin evolved with eukaryotes and acquired functional capacity in the densely packed intracellular environment. Given the decades of discovery on the structure and function of CCT, much remains unknown such as the scope of its interactome. New findings on the role of CCT in disease, and potential for diagnostic and therapeutic uses, heighten the need to better understand the function of this essential molecular chaperone. Clues as to how CCT causes cancer or neurological disorders lie in the early studies of the chaperonin that form a foundational knowledgebase. In this review, we span the decades of CCT discoveries to provide critical context to the continued research on the diverse capacities in health and disease of this essential protein-folding complex.

Analysis of Effects of PTEN-Mediated TGF-β/Smad2 Pathway on Osteogenic Differentiation in Osteoporotic Tibial Fracture Rats and Bone Marrow Mesenchymal Stem Cell under Tension

Purpose. To discuss effects of phosphatase and tensin homolog protein (PTEN)-mediated transforming growth factor-β (TGF-β)/Smad homologue 2 (Smad2) pathway on osteogenic differentiation in osteoporotic (OP) tibial fracture rats and bone marrow mesenchymal stem cell (BMSC) under tension. Methods. A tibial fracture model was established. The rats were divided into sham-operated group and model group, and tibia tissue was collected. Purchase well-grown cultured rat BMSC, and use the Flexercell in vitro cell mechanics loading device to apply tension. The expression of PTEN was detected by qRT-PCR. After the BMSCs were transfected with si-PTEN and oe-PTEN, the force was applied to detect cell differentiation. The expression of TGF-β/Smad2 protein was detected by Western blot. The formation of calcium nodules in BMSC was detected by alkaline phosphatase (ALP) staining and alizarin red (AR) staining. Results. The expression of PTEN was higher in the model group and tension MSC group, and the expression of TGF-β and Smad2 protein was lower. The expression of TGF-β and Smad2 protein in oe-PTEN group was lower than the oe-NC group and control group. The expression of TGF-β and Smad2 protein in si-PTEN group was higher than the si-NC group and control group. The results of ALP staining and AR staining also confirmed the above results. Conclusion. PTEN-mediated TGF-β/Smad2 pathway may play a key role in the osteogenic differentiation of OP tibial fracture rats. Downregulation of PTEN and upregulation of TGF-β/Smad2 signal can promote the osteogenic differentiation of BMSC under tension.

Matriptase-2/NR4A3 axis switches TGF-β action toward suppression of prostate cancer cell invasion, tumor growth, and metastasis

Dysregulation of pericellular proteolysis is strongly implicated in cancer metastasis through alteration of cell invasion and the microenvironment. Matriptase-2 (MT-2) is a membrane-anchored serine protease which can suppress prostate cancer (PCa) cell invasion. In this study, we showed that MT-2 was down-regulated in PCa and could suppress PCa cell motility, tumor growth, and metastasis. Using microarray and biochemical analysis, we found that MT-2 shifted TGF-β action towards its tumor suppressor function by repressing epithelial-to-mesenchymal transition (EMT) and promoting Smad2 phosphorylation and nuclear accumulation to upregulate two TGF-β1 downstream effectors (p21 and PAI-1), culminating in hindrance of PCa cell motility and malignant growth. Mechanistically, MT-2 could dramatically up-regulate the expression of nuclear receptor NR4A3 via iron metabolism in PCa cells. MT-2-induced NR4A3 further coactivated Smad2 to activate p21 and PAI-1 expression. In addition, NR4A3 functioned as a suppressor of PCa and mediated MT-2 signaling to inhibit PCa tumorigenesis and metastasis. These results together indicate that NR4A3 sustains MT-2 signaling to suppress PCa cell invasion, tumor growth, and metastasis, and serves as a contextual factor for the TGF-β/Smad2 signaling pathway in favor of tumor suppression via promoting p21 and PAI-1 expression.

HOXB2 increases the proliferation and invasiveness of colon cancer cells through the upregulation of CCT6A

Colon cancer has a high mortality rate, thus there is an urgent need to develop novel therapeutic options for clinical management of the disease. Studies have revealed that chaperonin containing TCP1 subunit 6A (CCT6A) promoted the development of multiple types of cancer, and dataset analysis revealed that homeobox B2 (HOXB2) has the potential to modulate the expression of CCT6A. However, whether HOXB2 affects the proliferation, migration and invasion of colon cancer cells remains to be determined. A CCT6A knockdown colon cancer cell line was established and colony formation, wound healing and Transwell invasion assays were performed to assess proliferation, migration and invasion of the altered colon cancer cells. Subsequently, luciferase reporter gene assays and chromatin immunoprecipitation assays were performed to detect the relationship between HOXB2 and CCT6A. A HOXB2 overexpression colon cancer cell line was established and the proliferation, migration and invasion of these cells was determined using the same methods. Knockdown of CCT6A reduced the proliferation, migration and invasion of colon cancer cells. HOXB2 enhanced the expression of CCT6A in colon cancer cells by binding to the promoter of CCT6A. Overexpression of HOXB2 abolished the inhibitory effect of CCT6A knockdown on the proliferation, migration and invasion of colon cancer cells. HOXB2 increased the proliferation and invasiveness of colon cancer cells by increasing the expression of CCT6A.

CCT6A expression in hepatocellular carcinoma and its correlation with clinical characteristics, liver function indexes, tumor markers and prognosis

BACKGROUND

Chaperonin-containing tailless complex polypeptide 1 subunit 6A (CCT6A) plays roles in cancer progression, but its clinical implication in hepatocellular carcinoma (HCC) management needs further exploration. This study aimed to explore the correlation of CCT6A with clinical characteristics, liver function indexes, tumor markers and prognosis in HCC patients.

METHODS

240 HCC patients were retrospectively enrolled. 240 pairs of cancer and adjacent specimens were used to evaluate CCT6A protein expression by immunohistochemistry assay; among which 184 pairs were used to assess CCT6A mRNA expression by reverse transcription-quantitative polymerase chain reaction.

RESULTS

Both CCT6A protein expression and CCT6A mRNA expression were higher in HCC tumor tissue than in adjacent tissue (P < 0.001). The receiver operating characteristic (ROC) curve showed that CCT6A had certain potential in discriminating tumor tissues from adjacent tissues. In addition, CCT6A protein expression was positively correlated with multifocal tumor nodule (P = 0.001), ≥ 5.0 cm tumor size (P = 0.028), BCLC stage (P = 0.002) and abnormal AFP (P = 0.021). Besides, CCT6A mRNA expression was associated with multifocal tumor nodule (P = 0.025), ≥ 5.0 cm tumor size (P = 0.018), higher BCLC stage (P = 0.036), abnormal CA199 (P = 0.027) and abnormal AFP (P = 0.008). However, no correlation was found in CCT6A with liver function indexes (all P ≥ 0.05). Moreover, CCT6A protein and mRNA high expressions were both correlated with poor accumulating overall survival (OS) (P = 0.004, P = 0.002, respectively). Furthermore, CCT6A protein high expression (vs. low) independently predicted shorter OS (P = 0.027).

CONCLUSIONS

CCT6A serves as a possible biomarker reflecting tumor features and prognostication in HCC patients.

The Autoantibodies against Tumor-Associated Antigens as Potential Blood-Based Biomarkers in Thyroid Neoplasia: Rationales, Opportunities and Challenges

The Autoantibodies targeting Tumor-Associated Antigens (TAA-AAbs) emerge as a result of a variety of tumor-related immunogenic stimuli and may be regarded as the eyewitnesses to the anti-tumor immune response. TAA-AAbs may be readily detected in peripheral blood to unveil the presence of a particular TAA-expressing tumor, and a fair number of TAAs eliciting the tumor-associated autoantibody response have been identified. The potential of TAA-AAbs as tumor biomarkers has been extensively studied in many human malignancies with a major influence on public health; however, tumors of the endocrine system, and, in particular, the well-differentiated follicular cell-derived thyroid neoplasms, remain understudied in this context. This review provides a detailed perspective on and legitimate rationales for the potential use of TAA-AAbs in thyroid neoplasia, with particular reference to the already established diagnostic implications of the TAA-AAbs in human cancer, to the windows for improvement and diagnostic niches in the current workup strategies in nodular thyroid disease and differentiated thyroid cancer that TAA-AAbs may successfully occupy, as well as to the proof-of-concept studies demonstrating the usefulness of TAA-AAbs in thyroid oncology, particularly for the pre-surgical discrimination between tumors of different malignant potential in the context of the indeterminate results of the fine-needle aspiration cytology.

CBX3 is associated with metastasis and glutathione/glycosphingolipid metabolism in colon adenocarcinoma

BACKGROUND

Metastasis is the major cause of colon adenocarcinoma (COAD) mortality. Increasing studies demonstrated that the epigenetics and downstream expression change of pivotal genes may act as a major role in promoting COAD progression and metastasis. Therefore, identifying the dysregulation of key genes associating with COAD metastasis may provide a new strategy for the discovery of potential treatment targets.

METHODS

This study included a single-cell RNA sequencing profile consisting of 17,469 tumor cells derived from 23 samples, and 326 COADs available from The Cancer Genome Atlas (TCGA), etc. The study was performed using comparative analysis to characterize the role of CBX3 in COAD metastasis and progression.

RESULTS

This study revealed that the mRNA level of Chromebox homolog 3 (CBX3) in the metastatic COAD was significantly higher than that of the primary COAD and normal colon tissues (Wilcoxon's rank-sum test, P<0.05). Activation of CBX3 was involved in regulating an interaction network consisting of CCT6A, LSM5, and GGCT, etc., which may subsequently participate in glutathione metabolism. Besides, CBX3 also exhibited a negative correlation with glycosphingolipid metabolism, which may associate with the regulation of CBX3 on DNA methylation. Clinical data analysis demonstrated that patients with high CBX3 mRNA levels showed a nearly 2-fold shorter overall survival time than the control group (hazard ratio =1.59; likelihood ratio test, P=0.04).

CONCLUSIONS

Our study demonstrated that CBX3 overexpression is associated with COAD metastasis. CBX3 downstream regulation network involves in TCP1 complex, LSM family, and glutathione metabolism, which may provide a potential target for suppressing tumor metastasis.

CAMSAP1 Mutation Correlates With Improved Prognosis in Small Cell Lung Cancer Patients Treated With Platinum-Based Chemotherapy

Platinum-based chemotherapy is the first-line treatment for small cell lung cancer (SCLC). However, due to patients developing a resistance to the drug, most experience relapse and their cancer can become untreatable. A large number of recent studies have found that platinum drug sensitivity of various cancers is affected by specific gene mutations, and so with this study, we attempted to find an effective genetic biomarker in SCLC patients that indicates their sensitivity to platinum-based drugs. To do this, we first analyzed whole exome sequencing (WES) and clinical data from two cohorts to find gene mutations related to the prognosis and to the platinum drug sensitivity of SCLC patients. The cohorts used were the Zhujiang cohort (N = 138) and the cohort reported by George et al. (N = 101). We then carried out gene set variation analysis (GSVA) and gene set enrichment analysis (GSEA) to investigate possible molecular mechanisms through which these gene mutations affect patient prognosis and platinum drug sensitivity. We found that for SCLC patients, CAMSAP1 mutation can activate anti-tumor immunity, mediate tumor cell apoptosis, inhibit epithelial-mesenchymal transition (EMT), improve prognosis, and improve platinum drug sensitivity, suggesting that CAMSAP1 mutation may be a potential biomarker indicating platinum drug sensitivity and patient prognosis in SCLC.

Overexpression of chaperonin containing TCP1 subunit 7 has diagnostic and prognostic value for hepatocellular carcinoma

Chaperonin containing TCP1 subunit 7 (CCT7) regulates the expression of many tumor-related proteins. We investigated the diagnostic and prognostic value of CCT7 expression for hepatocellular carcinoma (HCC). In datasets from The Cancer Genome Atlas and the Gene Expression Omnibus, CCT7 mRNA levels were greater in HCC tissues than adjacent normal tissues, and these results were validated using immunohistochemistry. In patients with early-stage disease and low alpha-fetoprotein expression, CCT7 expression was still higher in HCC tissues than normal tissues. Receiver operating characteristic curve analyses indicated that CCT7 expression had better diagnostic value than alpha-fetoprotein for HCC patients with early-stage disease and low alpha-fetoprotein expression. The positive predictive value of CCT7 expression was higher than that of alpha-fetoprotein expression. Higher CCT7 mRNA and protein levels were independent risk factors for poorer overall and recurrence-free survival in HCC patients. Greater methylation of the CpG site cg19515186 was associated with better overall survival in HCC patients. Genes co-expressed with CCT7 were upregulated in HCC and associated with poorer overall survival. Gene Ontology, Kyoto Encyclopedia of Genes and Genomes and Gene Set Enrichment Analyses demonstrated that CCT7 expression correlated with spliceosome signaling. These findings demonstrate that CCT7 has diagnostic and prognostic value for HCC.

MicroRNA-148a/152 cluster restrains tumor stem cell phenotype of colon cancer via modulating CCT6A

Accumulating evidence has presented that microRNA-148a/152 (miR-148a/152) acts as the tumor inhibitor in various cancers. In this article, we aimed to probe the inhibition of colon cancer stem cells by miR-148a/152 cluster via regulation of CCT6A. miR-148a/152 and CCT6A expression in colon cancer tissues and cells was detected. The relationship between miR-148a/152 expression and the clinicopathological features of patients with colon cancer was analyzed. Colon cancer stem cells (CD44+/CD133+) were selected and high/low expression of miR-148a/152 plasmids were synthesized to intervene CD44+/CD133+ colon cancer stem cells to investigate the function of miR-148a/152 in invasion, migration, proliferation, colony formation and apoptosis of cells. The growth status of nude mice was observed to verify the in-vitro results. The relationship between miR-148a/152 and CCT6A was analyzed. CCT6A upregulated and miR-148a/152 downregulated in colon cancer tissues. MiR-148a/152 expression was correlated with tumor node metastasis stage, lymph node metastasis and differentiation degree. Upregulated miR-148a/152 depressed CCT6A expression and restrained invasion and migration ability, colony formation and proliferation, induced cell apoptosis, depressed OCT4, Nanog and SOX2 mRNA expression of colon cancer stem cells, and descended tumor weight and volume in nude mice. CCT6A was a target gene of miR-148a/152. Overexpression of CCT6A protected colon cancer stem cells. Functional studies showed that upregulation of miR-148a/152 can suppress the migration, invasion and proliferation of CD44+/CD133+ colon cancer stem cells, advance its apoptosis via inhibition of CCT6A expression.

Loss of ATF4 leads to functional aging-like attrition of adult hematopoietic stem cells

Aging of hematopoietic stem cells (HSCs) directly contributes to dysfunction of hematopoietic and immune systems due to aging-associated alterations in HSC features. How the function of adult HSCs is regulated during aging so that relevant pathologic abnormalities may occur, however, remains incompletely understood. Here, we report that ATF4 deficiency provokes severe HSC defects with multifaceted aging-like phenotype via cell-autonomous mechanisms. ATF4 deletion caused expansion of phenotypical HSCs with functional attrition, characterized by defective repopulating and self-renewal capacities and myeloid bias. Moreover, the ATF4^−/− HSC defects were associated with elevated mitochondrial ROS production by targeting HIF1α. In addition, loss of ATF4 significantly delayed leukemogenesis in the MLL-AF9–induced leukemia model. Mechanistically, ATF4 deficiency impaired HSC function with aging-like phenotype and alleviated leukemogenesis by regulating HIF1α and p16^Ink4a. Together, our findings suggest a possibility of developing new strategies for the prevention and management of HSC aging and related pathological conditions.

[Identification of potential regulatory genes for embryonic stem cell self-renewal and pluripotency by random forest]

OBJECTIVE

To identify novel genes associated with self-renewal and pluripotency of mouse embryonic stem cells(mESCs)by integrating multiomics data based on machine learning methods.

METHODS

We integrated multiomics information of mESCs involving transcriptome, histone modifications, chromatin accessibility, transcription factor binding and architectural protein binding, and compared the signal differences between known stem cell self-renewal and pluripotency genes and other genes.By integrating these multiomics data, we established prediction models based on several machine learning classifiers including random forests and performed 5-fold cross validations.The model was trained using the training dataset containing two thirds of the input samples, and the remaining one third of the input samples were used as the test dataset to assess the performance of the model in independent tests.Finally, the results predicted by the model were validated through gene function annotation and cell function experiments including cell viability assay, colony formation assay and cell cycle analysis.

RESULTS

Compared with the random genes, the genes known to be associated with self-renewal and pluripotency of mESCs in the multiomics data showed significantly different features.Random forest outperformed the other machine learning algorithms tested on these multiomics data, with an area under the curve (AUC) of 0.883±0.018 for cross validation and an AUC of 0.880±0.028 for independent test.Based on this model, we identified 893 potential regulatory genes associated wwith self-renewal and pluripotency of mESCs, which were similar to the known genes in functional annotation.Known-down of the predicted novel regulator gene Cct6a resulted in significant decreases in the cell viability of mESCs (P < 0.0001) and the number of cell clones (P < 0.01), significantly increased the number of cells in G1 phase (P < 0.01) and decreasedthe number of S phase cells (P < 0.05).Knockdown of Cct6a also led to failure of positive alkaline phosphatase staining of the mESCs.

CONCLUSION

Machine learning model based on multiomics data can be used to predict potential self-renewal and pluripotency regulators with high performance.By using this model, we predicted potential self-renewal and pluripotency regulatory genes including Cct6a and applied experimental validation.This model provides new insights into the regulatory mechanism of mESCs and contribute to stem cell research.

Chaperonin-containing tailless complex polypeptide 1 subunit 6A correlates with increased World Health Organization grade, less isocitrate dehydrogenase mutation, and deteriorative survival of astrocytoma patients

Objective

Chaperonin‐containing tailless complex polypeptide 1 subunit 6A (CCT6A) is reported to be an efficient prognostic biomarker in various cancers, but it is rarely reported in astrocytoma. Thus, this study aimed to evaluate the expression of CCT6A and its correlation with disease features and prognosis in astrocytoma patients.

Methods

Totally, 198 astrocytoma patients who received surgery treatment were enrolled. CCT6A protein expression was determined in the tumor tissues fixed in formalin and embedded in paraffin (FFEP) by immunohistochemistry (IHC) assay. In addition, 133 out of 198 astrocytoma patients had fresh tumor tissues frozen in the liquid nitrogen for the determination of CCT6A mRNA expression by reverse transcription‐quantitative polymerase chain reaction.

Results

Sixty‐nine (34.8%), 70 (35.4%), 46 (23.2%), and 13 (6.6%) astrocytoma patients had the CCT6A immunohistochemistry (IHC) score of 0–3, 4–6, 7–9, and 10–12, respectively. CCT6A protein expression was correlated with increased World Health Organization (WHO) grade (P < 0.001) and less isocitrate dehydrogenase (IDH) mutation (P = 0.002); meanwhile, CCT6A mRNA expression was only related to elevated WHO grade (P = 0.001). However, CCT6A protein and mRNA expression were not correlated with other clinical features and subsequent treatment modalities (all P > 0.05). Moreover, CCT6A protein high and CCT6A mRNA high were related to shorter accumulating overall survival (OS; both P < 0.05). CCT6A protein high was an independent factor for predicting the worse OS (hazard ratio: 1.821, P = 0.012).

Conclusion

Chaperonin‐containing tailless complex polypeptide 1 subunit 6A correlates with elevated WHO grade and less IDH mutation; besides, CCT6A high expression is independently associated with unfavorable accumulating OS of astrocytoma patients.

CCT6A may act as a potential biomarker reflecting tumor size, lymphatic metastasis, FIGO stage, and prognosis in cervical cancer patients

OBJECTIVE

Chaperonin-containing tailless complex polypeptide subunit 6A (CCT6A) is a critical regulator and newly identified clinical biomarker of several cancers, while its correlation with the clinical characteristics and prognosis of cervical cancer patients is unclear. Therefore, this study aimed to explore this issue.

METHODS

Chaperonin-containing tailless complex polypeptide subunit 6A expression in tumor and tumor-adjacent tissues from 198 cervical cancer patients who underwent resection were detected by immunohistochemistry assay and reverse transcription-quantitative polymerase chain reaction. Besides, the clinicopathological features and survival data of cervical cancer patients were collected.

RESULTS

Chaperonin-containing tailless complex polypeptide subunit 6A protein and mRNA levels were both increased in tumor tissues compared with tumor-adjacent tissues (both p < 0.001). Receiver operating characteristic curves showed that CCT6A protein (AUC: 0.774, 95% CI: 0.729-0.819) and mRNA levels (AUC: 0.904, 95% CI: 0.874-0.934) well discriminated tumor tissues from tumor-adjacent tissues. Besides, correlation analyses found that CCT6A protein and mRNA levels were positively correlated with lymph node metastasis and FIGO stage (all p < 0.05), apart from which CCT6A mRNA level was also positively associated with tumor size (p = 0.032). In addition, CCT6A protein and mRNA levels were negatively correlated with accumulating disease-free survival (both p < 0.05); meanwhile CCT6A mRNA level was negatively associated with accumulating overall survival as well (p = 0.010).

CONCLUSION

Chaperonin-containing tailless complex polypeptide subunit 6A is elevated in tumor tissues, and its high expression associates with larger tumor size, lymph node metastasis, higher FIGO stage, and worse prognosis in cervical cancer patients.

Long non-coding RNA LEISA promotes progression of lung adenocarcinoma via enhancing interaction between STAT3 and IL-6 promoter

Long non-coding RNAs (lncRNAs) are emerging as a new class of regulators for a variety of biological processes and have been suggested to play pivotal roles in cancer development and progression. Our current study found that a lncRNA, designated enhancing IL-6/STAT3 signaling activation (LEISA, ENST00000603468), functioned as an oncogenic lncRNA in lung adenocarcinoma (LAD), a major form of non-small cell lung carcinoma, which is one of the most frequently diagnosed malignancies with high morbidity and mortality worldwide, and was involved in the regulation of STAT3 induced IL-6 transcription. Our data showed that LEISA was highly expressed in, and correlated with the clinical progression and prognosis of LAD. Ectopic expression of LEISA promoted the proliferation and suppressed apoptosis of LAD cells in vitro and in vivo. Mechanistically, we demonstrated that LEISA recruited STAT3 to bind the promoter of IL-6 and upregulated IL-6 expression. Taken together, our work identifies LEISA as a potential diagnostic biomarker and therapeutic target for LAD.

SMAD4 mutation correlates with poor prognosis in non-small cell lung cancer

SMAD4 is an intracellular signaling mediator of the TGF-β pathway. Its mutation was commonly observed in gastrointestinal cancers, such as pancreatic cancer. The loss of SMAD4 on immunohistochemical staining is often used to suggest a pancreaticobiliary differentiation in evaluating a metastatic adenocarcinoma with unknown origin. However, the function and molecular mechanism of SMAD4 in non-small cell lung cancer (NSCLC) development are largely unknown. Thus, we studied the correlation between SMAD4 mutations and clinico-molecular features in the patients with NSCLC. We reported the frequencies and prognostic values of SMAD4 mutations in a Chinese NSCLC cohort using next-generation sequencing. The NSCLC cases from several public databases, including The Cancer Genome Atlas and others, were also used in this study to elucidate SMAD4-related molecular partners and mechanisms. Integrated bioinformatics analyses were conducted, such as analysis of Gene Ontology enrichment analysis, gene set enrichment analysis (GSEA), and survival analysis. Immunohistochemistry showed that the tissues harboring SMAD4 mutations tended to show SMAD4 deficiency or loss, while SMAD4 expression was significantly reduced at all stages of NSCLC cases. We found that reduced SMAD4 expression was more frequent in the patients with poor disease-free survival and resistance to platinum-based chemotherapy. SMAD4 mutation was an independent risk factor for the survival of NSCLC patients. The expression of SMAD4 was associated with that of SMAD2. The GSEA showed that SMAD4 might promote NSCLC progression by regulating proliferation, adhesion, and immune response. In conclusion, these data suggest that SMAD4 mutation or loss as well as reduced expression can be used to identify the NSCLC patients with poor survival and resistance to platinum-based chemotherapy. SMAD4 may be a predictive marker or therapeutic target in NSCLC. The source code and user's guide are freely available at Github: https://github.com/wangyue77-ab/smad4 .

Two predicted models based on ceRNAs and immune cells in lung adenocarcinoma

Background

It is well accepted that both competitive endogenous RNAs (ceRNAs) and immune microenvironment exert crucial roles in the tumor prognosis. The present study aimed to find prognostic ceRNAs and immune cells in lung adenocarcinoma (LUAD).

Materials and Methods

More specifically, we explored the associations of crucial ceRNAs with the immune microenvironment. The Cancer Genome Atlas (TCGA) database was employed to obtain expression profiles of ceRNAs and clinical data. CIBERSORT was utilized to quantify the proportion of 22 immune cells in LUAD.

Results

We constructed two cox regression models based on crucial ceRNAs and immune cells to predict prognosis in LUAD. Subsequently, seven ceRNAs and seven immune cells were involved in prognostic models. We validated both predicted models via an independent cohort GSE72094. Interestingly, both predicted models proved that the longer patients were smoking, the higher risk scores would be obtained. We further investigated the relationships between seven genes and immune/stromal scores via the ESTIMATE algorithm. The results indicated that CDC14A and H1F0 expression were significantly related to stromal scores/immune scores in LUAD. Moreover, based on the result of the ceRNA model, single-sample gene set enrichment analysis (ssGSEA) suggested that differences in immune status were evident between high- and low-risk groups.

Systematic Characterization of Expression Profiles and Prognostic Values of the Eight Subunits of the Chaperonin TRiC in Breast Cancer

Background

Chaperonin-containing TCP-1 (TRiC or CCT) was demonstrated to be involved in oncogenesis of cancers carcinogenesis and development of various malignancies. Increasing experimental evidence indicated that dysregulation of TRiC was implicated in the tumor progression of breast cancer (BCa). However, few definitive studies have addressed the diverse expression patterns and prognostic values of eight TRiC subunits. Thus, we aimed to investigate the clinical significance of TRiC subunit expression and prognostic values for their possible implications in diagnosis and treatment of BCa.

Methods

Based on updated public resources and comprehensive bioinformatics analysis, we used some online databases (e.g., UALCAN, GEPIA, cBioPortal, TIMER, BC-GenExMiner, metascape, and GeneMANIA) to comprehensively explore the expression levels and the prognostic effects of eight TRiC subunits in patients with BCa.

Results

The transcriptional levels of most subunits of the Chaperonin TRiC (CCT2, CCT3, CCT4, CCT5, CCT6A, and CCT7) were significantly elevated compared with normal breast tissues, whereas TCP1, CCT4, and CCT6B were lower in BCa tissues than in normal tissues. Besides, copy-number alterations (CNA) of eight TRiC subunits positively regulated their mRNA expressions. Furthermore, high mRNA expression of TCP1/CCT2/CCT4/CCT5/CCT6A/CCT7/CCT8 was significantly associated with poor overall survival (OS) in BCa patients. The eight subunits of the chaperonin TRiC was related to tumor purity and immune infiltration levels of BCa. Co-expression analysis showed CCT6B was negatively associated with other subunits of TRiC and other subunits of TRiC were positively correlated with each other. Additionally, TRiC and their interactive proteins were correlated with positive regulation of biological process, localization, and biological regulation.

Conclusion

This study systematically illustrated the expression profiles and distinct prognostic values of chaperonin TRiC in BCa, providing insights for further investigation of subunits of the chaperonin TRiC as novel therapeutic targets and potential prognostic biomarkers in BCa.

Derivation and Validation of a Prognostic Model for Cancer Dependency Genes Based on CRISPR-Cas9 in Gastric Adenocarcinoma

As a CRISPR-Cas9-based tool to help scientists to investigate gene functions, Cancer Dependency Map genes (CDMs) include an enormous series of loss-of-function screens based on genome-scale RNAi. These genes participate in regulating survival and growth of tumor cells, which suggests their potential as novel therapeutic targets for malignant tumors. By far, studies on the roles of CDMs in gastric adenocarcinoma (GA) are scarce and only a small fraction of CDMs have been investigated. In the present study, datasets of the differentially expressed genes (DEGs) were extracted from the TCGA-based (The Cancer Genome Atlas) GEPIA database, from which differentially expressed CDMs were determined. Functions and prognostic significance of these verified CDMs were evaluated using a series of bioinformatics methods. In all, 246 differentially expressed CDMs were determined, with 147 upregulated and 99 downregulated. Ten CDMs (ALG8, ATRIP, CCT6A, CFDP1, CINP, MED18, METTL1, ORC1, TANGO6, and PWP2) were identified to be prognosis-related and subsequently a prognosis model based on these ten CDMs was constructed. In comparison with that of patients with low risk in TCGA training, testing and GSE84437 cohort, overall survival (OS) of patients with high risk was significantly worse. It was then subsequently demonstrated that for this prognostic model, area under the ROC (receiver operating characteristic) curve was 0.771 and 0.697 for TCGA training and testing cohort respectively, justifying its reliability in predicting survival of GA patients. With the ten identified CDMs, we then constructed a nomogram to generate a clinically practical model. The regulatory networks and functions of the ten CDMs were then explored, the results of which demonstrated that as the gene significantly associated with survival of GA patients and Hazard ratio (HR), PWP2 promoted in-vitro invasion and migration of GA cell lines through the EMT signaling pathway. Therefore, in conclusion, the present study might help understand the prognostic significance and molecular functions of CDMs in GA.

HOMER3 facilitates growth factor-mediated β-Catenin tyrosine phosphorylation and activation to promote metastasis in triple negative breast cancer

BACKGROUND

HOMER family scaffolding proteins (HOMER1-3) play critical roles in the development and progression of human disease by regulating the assembly of signal transduction complexes in response to extrinsic stimuli. However, the role of HOMER protein in breast cancer remains unclear.

METHODS

HOMER3 expression was examined by immunohistochemistry in breast cancer patient specimens, and its significance in prognosis was assessed by Kaplan-Meier survival analysis. The effects of HOMER3 in growth factor-induced β-Catenin activation were analyzed by assays such as TOP/FOP flash reporter, tyrosine phosphorylation assay and reciprocal immunoprecipitation (IP) assay. Role of HOMER3 in breast cancer metastasis was determined by cell function assays and mice tumor models.

RESULTS

Herein, we find that, among the three HOMER proteins, HOMER3 is selectively overexpressed in the most aggressive triple negative breast cancer (TNBC) subtype, and significantly correlates with earlier tumor metastasis and shorter patient survival. Mechanismly, HOMER3 interacts with both c-Src and β-Catenin, thus providing a scaffolding platform to facilitate c-Src-induced β-Catenin tyrosine phosphorylation under growth factor stimulation. HOMER3 promotes β-Catenin nuclear translocation and activation, and this axis is clinically relevant. HOMER3 promotes and is essential for EGF-induced aggressiveness and metastasis of TNBC cells both in vitro and in vivo.

CONCLUSION

These findings identify a novel role of HOMER3 in the transduction of growth factor-mediated β-Catenin activation and suggest that HOMER3 might be a targetable vulnerability of TNBC.

Prognostic Power of a Chaperonin Containing TCP-1 Subunit Genes Panel for Hepatocellular Carcinoma

Chaperonin containing TCP-1 (T-complex protein 1) (CCT) is a large molecular weight complex that contains nine subunits (TCP1, CCT2, CCT3, CCT4, CCT5, CCT6A, CCT6B, CCT7, CCT8). This study aimed to reveal key genes which encode CCT subunits for prognosis and establish prognostic gene signatures based on CCT subunit genes. The data was downloaded from The Cancer Genome Atlas, International Cancer Genome Consortium and Gene Expression Omnibus. CCT subunit gene expression levels between tumor and normal tissues were compared. Corresponding Kaplan-Meier analysis displayed a distinct separation in the overall survival of CCT subunit genes. Correlation analysis, protein-protein interaction network, Gene Ontology analysis, immune cells infiltration analysis, and transcription factor network were performed. A nomogram was constructed for the prediction of prognosis. Based on multivariate Cox regression analysis and shrinkage and selection method for linear regression model, a three-gene signature comprising CCT4, CCT6A, and CCT6B was constructed in the training set and significantly associated with prognosis as an independent prognostic factor. The prognostic value of the signature was then validated in the validation and testing set. Nomogram including the signature showed some clinical benefit for overall survival prediction. In all, we built a novel three-gene signature and nomogram from CCT subunit genes to predict the prognosis of hepatocellular carcinoma, which may support the medical decision for HCC therapy.

Proteomic analysis of radio-resistant breast cancer xenografts: Increased TGF-β signaling and metabolism

Our previous studies have shown that MCF-7 breast cancer cell line exposed to 6 Gy and allowed to recover for 7 days (D7-6G) developed radio-resistance. In this study, we have tested the ability of these cells to form tumors in severe combined immunodeficiency (SCID) mice and characterized these tumors by proteomic analyses. Untreated (MCF-C) and D7-6G cells (MCF-R) were injected s.c. in SCID mice and tumor growth monitored. On Day 18, the mice were killed and tumor tissues were fixed in formalin or RNA later. Expression of genes was assessed by reverse transcription-polymerase chain reaction and proteins by enzyme-linked immunosorbent assay/antibody labeling and flow cytometry. Label free proteomic analyses was carried out by liquid chromatography-mass spectrometry. Metabolic analysis was carried out using Seahorse analyzer. MCF-R cells had a shorter latency and formed larger tumors. These tumors were characterized by an increased expression of transforming growth factor β (TGF-β) isoforms; its downstream genes pSMAD3, Snail-1, Zeb-1, HMGA2; hybrid epithelial/mesenchymal phenotype; migration, enrichment of cancer stem cells and radioresistance following challenge dose of radiation. Proteomic analysis of MCF-7R tumors resulted in identification of a total of 649 differentially expressed proteins and pathway analyses using protein annotation through evolutionary relationship indicated enrichment of genes involved in metabolism. Data are available via ProteomeXchange with identifier PXD022506. Seahorse analyzer confirmed increased metabolism in these cells with increased oxidative phosphorylation as well as glycolysis. Increased uptake of 2-NBDG further confirmed increased glycolysis. In summary, we demonstrate that radioresistant breast cancer cells had an enrichment of TGF-β signaling and increased metabolism.

PTPRε Acts as a Metastatic Promoter in Hepatocellular Carcinoma by Facilitating Recruitment of SMAD3 to TGF-β Receptor 1

BACKGROUND AND AIMS

Transforming growth factor beta (TGF-β) suppresses early stages of tumorigenesis, but contributes to the migration and metastasis of cancer cells. However, the role of TGF-β signaling in invasive prometastatic hepatocellular carcinoma (HCC) is poorly understood. In this study, we investigated the roles of canonical TGF-β/mothers against decapentaplegic homolog 3 (SMAD3) signaling and identified downstream effectors on HCC migration and metastasis.

APPROACH AND RESULTS

By using in vitro trans-well migration and invasion assays and in vivo metastasis models, we demonstrated that SMAD3 and protein tyrosine phosphatase receptor epsilon (PTPRε) promote migration, invasion, and metastasis of HCC cells in vitro and in vivo. Further mechanistic studies revealed that, following TGF-β stimulation, SMAD3 binds directly to PTPRε promoters to activate its expression. PTPRε interacts with TGFBR1/SMAD3 and facilitates recruitment of SMAD3 to TGFBR1, resulting in a sustained SMAD3 activation status. The tyrosine phosphatase activity of PTPRε is important for binding with TGFBR1, recruitment and activation of SMAD3, and its prometastatic role in vitro. A positive correlation between pSMAD3/SMAD3 and PTPRε expression was determined in HCC samples, and high expression of SMAD3 or PTPRε was associated with poor prognosis of patients with HCC.

CONCLUSIONS

PTPRε positive feedback regulates TGF-β/SMAD3 signaling to promote HCC metastasis.

MicroRNA-148a-3p inhibits progression of hepatocelluar carcimoma by repressing SMAD2 expression in an Ago2 dependent manner

Background

Hepatocellular carcinoma (HCC) is one of the most prevalent common cancer worldwide with high mortality. Transforming growth factor-β (TGF-β) signaling pathway was reported dysregulated during liver cancer formation and progression. As a key component of TGF-β signaling, the role of SMAD2 and its regulatory mechanisms in HCC remain unclear.

Methods

SMAD2 expression in paired HCC specimens were determined by western blot and immunohistochemistry (IHC). quantitative real-time PCR (qRT-PCR) was used to measure mRNA and microRNA (miRNA) expression level. Cell migration, invasion and proliferation ability were evaluated by transwell, CCK8 and EdU assay. In silico websites were used to manifest overall survival rates of HCC patients or to predict miRNAs targeting SMAD2. Dual luciferase reporter assay and anti-Ago2 immunoprecipitation assay were performed to confirm the binding between SMAD2 mRNA and miRNA-148a-3p (miR-148a). Tumorigenesis and lung metastasis mouse model were used to explore the role of miR-148a in vivo. In situ hybridization (ISH) was conducted to determine the expression of miR-148a in liver tissues.

Results

In this study, we found that SMAD2 was highly expressed in HCC and elevated SMAD2 expression predicted shorter overall survival (OS) time for HCC patients. SMAD2 promoted mobility and proliferation of HCC cells in vitro. We further revealed that the expression of miR-148a was negatively correlated with SMAD2 and found that miR-148a repressed SMAD2 expression by downregulating its mRNA through binding with Argonaute 2 (Ago2) in HCC. Transwell, CCK8 and animal experiments exhibited miR-148a inhibited metastasis and proliferation of HCC in vitro and in vivo. Moreover, the phenotype changes caused by miR-148a manipulation were recovered by rescuing SMAD2 expression in HCC cells. ISH assay indicated miR-148a was downregulated in HCC and low expression of miR-148a associated with more aggressive clinic features and poor prognosis.

Conclusion

miR-148a was identified as a repressor of HCC progression by downregulating SMAD2 in an Ago2 dependent manner.

PDLIM5 inhibits STUB1-mediated degradation of SMAD3 and promotes the migration and invasion of lung cancer cells

Transforming growth factor β (TGFβ) signaling plays an important role in regulating tumor malignancy, including in non-small cell lung cancer (NSCLC). The major biological responses of TGFβ signaling are determined by the effector proteins SMAD2 and SMAD3. However, the regulators of TGFβ-SMAD signaling are not completely revealed yet. Here, we showed that the scaffolding protein PDLIM5 (PDZ and LIM domain protein 5, ENH) critically promotes TGFβ signaling by maintaining SMAD3 stability in NSCLC. First, PDLIM5 was highly expressed in NSCLC compared with that in adjacent normal tissues, and high PDLIM5 expression was associated with poor outcome. Knockdown of PDLIM5 in NSCLC cells decreased migration and invasion in vitro and lung metastasis in vivo In addition, TGFβ signaling and TGFβ-induced epithelial-mesenchymal transition was repressed by PDLIM5 knockdown. Mechanistically, PDLIM5 knockdown resulted in a reduction of SMAD3 protein levels. Overexpression of SMAD3 reversed the TGFβ-signaling-repressing and anti-migration effects induced by PDLIM5 knockdown. Notably, PDLIM5 interacted with SMAD3 but not SMAD2 and competitively suppressed the interaction between SMAD3 and its E3 ubiquitin ligase STUB1. Therefore, PDLIM5 protected SMAD3 from STUB1-mediated proteasome degradation. STUB1 knockdown restored SMAD3 protein levels, cell migration, and invasion in PDLIM5-knockdown cells. Collectively, our findings indicate that PDLIM5 is a novel regulator of basal SMAD3 stability, with implications for controlling TGFβ signaling and NSCLC progression.

Chaperonin containing t-complex polypeptide 1 subunit 6A correlates with lymph node metastasis, abnormal carcinoembryonic antigen and poor survival profiles in non-small cell lung carcinoma

Background

This study aimed to investigate the correlation of chaperonin containing t-complex polypeptide 1 subunit 6A (CCT6A) expression with clinicopathological features and survival profiles in non-small cell lung carcinoma (NSCLC) patients.

Methods

A total of 381 NSCLC patients with Tumor, Node, Metastasis (TNM) stage I–IIIA who underwent tumor resection were retrospectively screened. Immunohistochemistry staining and semi-quantitative scoring were used to evaluate CCT6A expression in tumor and adjacent tissues. Clinicopathological features were retrieved. Disease-free survival (DFS) and overall survival (OS) were calculated.

Results

CCT6A expression was elevated in tumor tissue (CCT6A high 47.5% vs. low 52.5%) compared with adjacent tissue (CCT6A high 30.4% vs. low 69.6%) (P < 0.001), and ROC curve displayed that CCT6A could distinguish tumor tissue from adjacent tissue. Moreover, tumor CCT6A high expression was associated with lymph node metastasis (P = 0.001), elevated TNM stage (P = 0.002), and abnormal carcinoembryonic antigen (P = 0.022). Kaplan–Meier curves displayed that tumor CCT6A high expression was negatively correlated with DFS and OS (all P < 0.001). Cox’s regression analysis disclosed that tumor CCT6A high expression independently predicted worse DFS (P < 0.001) (hazard ratio (HR) 1.659 (95% confidence interval (CI) 1.318–2.089)), and OS (P < 0.001) (HR 1.779 (95%CI 1.378–2.298)).

Conclusions

CCT6A may present some clinical value in the management of NSCLC.

Identification of cofilin-1 as a novel mediator for the metastatic potentials and chemoresistance of the prostate cancer cells

Prostate cancer (PCa) is the most common malignancy among men. Tumor metastasis and chemoresistance contribute to the major cause of the mortality. In this study, we compared the protein profiles of two prostate cancer cell lines with different metastatic potentials, and identified cofilin-1 (CFL1) was one of the most differentially expressed proteins between two cell lines. Further results suggested that cofilin-1 promoted the remodeling of F-actin cytoskeleton, and enhanced the proliferation, migration and invasion of the prostate cancer cells via activation of P38 MAPK signaling pathway. In addition, cofilin-1 elevated the expression and drug efflux activity of multidrug resistance protein 1 (MDR1) by P38 MAPK signaling pathway, resulting in decrease of the adriamycin-induced apoptosis as well as the lytic cell death, and the subsequent resistance against adriamycin. Collectively, cofilin-1 might serve as a novel target candidate for both inhibiting the metastasis and reversing the chemoresistance of PCa.