Increased CCT5 expression is a potential unfavourable factor promoting the growth of nasopharyngeal carcinoma.

OBJECTIVE: Chaperonin containing TCP1 subunit 5 (CCT5) encodes the CCT5 protein subunit of chaperonin-containing TCP-1 (CCT/TRiC) complex, and is shown to be upregulated in tumour pathogenesis. The study aim was to investigate the differential expression of CCT5 between nasopharyngeal carcinoma (NPC) and noncancerous nasopharyngeal tissues, and the correlation between CCT5 expression and clinicopathological parameters/prognosis in patients with NPC. METHODS: Microarray assay data were evaluated for differential expression between NPC and noncancerous nasopharyngeal tissues. CCT5 expression in NPC and noncancerous nasopharyngeal tissues was determined at mRNA and protein levels by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and immunohistochemistry. Relationships between CCT5 expression in NPC, clinical parameters, and prognosis were statistically analysed. CCT5-mediated cell proliferation was assessed using EdU and cell counting kit-8. Western blot and co-immunoprecipitation were utilized to explore E3 ubiquitin-protein ligase parkin (PARK2)-induced degradation of CCT5. RESULTS: Microarray data showed CCT5 levels to be significantly increased in NPC versus noncancerous nasopharyngeal tissues, which was confirmed by qRT-PCR and immunohistochemical assays. Increased CCT5 protein levels positively correlated with tumour size, tumour recurrence, and clinical stage, and inversely correlated with patient's overall survival. Multivariate Cox regression analysis showed that enhanced CCT5 protein expression is an independent prognostic factor for patients with NPC. Overexpression of CCT5 markedly induced NPC cell proliferation. Finally, PARK2, as a suppressive E3 ubiquitin-ligase enzyme, was shown to bind CCT5 and induce degradation in NPC. CONCLUSIONS: Increased CCT5 may be an unfavourable factor promoting NPC growth. Binding of PARK2 to CCT5 was associated with CCT5 degradation, suggesting that PARK2 is an upstream negative modulator in NPC.

CCT2 Regulates ZEB1-Induced EMT Gene Transcription to Promote the Metastasis and Tumorigenesis of Papillary Thyroid Carcinoma.

BACKGROUND: Papillary thyroid carcinoma (PTC) is the most common malignant tumor of the thyroid, and its invasiveness and metastatic ability are closely related to patient prognosis. Chaperonin containing TCP1 subunit 2 (CCT2) is an important component of the molecular chaperone protein complex and has been shown to regulate cell proliferation and migration in various tumors. Epithelial-mesenchymal transition (EMT) is a critical process in tumor metastasis, and Zinc Finger E-Box Binding Homeobox 1 (ZEB1) is a core transcription factor that regulates EMT. This study aims to explore how CCT2 induces EMT gene transcription through ZEB1, thereby promoting the metastasis and tumorigenesis of PTC. METHODS: CCT2 in PTC tissues was analyzed using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot. siRNA and overexpression vectors were used to silence and overexpress CCT2, respectively, and the effects on PTC cell migration, invasion, proliferation, and apoptosis were observed. Rescue experiments were used to investigate the effect of CCT2 on ZEB1 and EMT-related genes. Cell apoptosis was detected by Terminal deoxynucleotidyl transferase dUTP Nick End Labeling (TUNEL) assay. Silencing ZEB1 was used to verify its effect on the oncogenic activity of CCT2. RESULTS: CCT2 was found to be highly expressed in PTC tissues (p < 0.01). In in vitro and in vivo experiments, silencing CCT2 inhibited the migration and invasion of PTC cells and their metastasis, while overexpression of CCT2 produced the opposite effect. Additionally, CCT2 promoted PTC cell proliferation and inhibited apoptosis (p < 0.01). Mechanistic studies revealed that CCT2 upregulated ZEB1 expression (p < 0.01), thereby inducing EMT gene transcription (p < 0.01). Silencing ZEB1 reduced the oncogenic effect of CCT2. CONCLUSION: This study first revealed the high expression of CCT2 in PTC and its essential role in the migration, invasion, proliferation, and anti-apoptosis of tumor cells. CCT2 promotes the metastasis and tumorigenesis of PTC by regulating ZEB1 and EMT-related genes. These findings provide new potential targets for molecular targeted therapy of PTC and explore new directions for future clinical treatment strategies.

Chaperonin-containing TCP-1 subunit genes are potential prognostic biomarkers and are correlated with Th2 cell infiltration in lung adenocarcinoma: An observational study.

A family of molecular chaperone complexes called chaperonin-containing T-complex protein 1 (TCP-1) subunit genes (CCTs) aids in the folding of numerous proteins. With regard to lung adenocarcinoma (LUAD), this study provided a thorough understanding of the diagnostic and prognostic use of CCTs. The expression of CCTs in LUAD was evaluated by using databases including UALCAN and the Gene Expression Omnibus. Immunohistochemistry (IHC) was conducted to validate the expression of CCTs in LUAD. The mutation in the CCTs was identified through the cBioPortal database, while promoter methylation was measured by the UALCAN database. The prognostic value of CCTs was evaluated using the PrognoScan analysis. The GEPIA2.0 database was used to measure the prognostic value of CCTs and associated Hub genes. Correlation analysis between CCTs expression in LUAD was based on the GEPIA2.0 database. The ROC curves, clinical correlation analysis, gene ontology, Kyoto Encyclopedia of Genes and Genome analysis, and immune cell infiltration analysis were downloaded from The Cancer Genome Atlas database and then analyzed and visualized using the R language. The STRING database was used for protein-protein interaction analysis. Upregulation of CCTs expression in patients with LUAD indicated advanced diseases and a poor prognosis. ROC curve analysis revealed that the CCTs may serve as diagnostic indicators. The functional enrichment analysis showed that CCTs were involved in the mitosis-mediated cell cycle process. Additionally, 10 hub genes associated with CCTs that were linked to LUAD prognosis and tumor progression were identified. Immune cell infiltration analysis showed that CCTs expression in tumor tissues tends to be related to T helper type 2 cell infiltration. This study revealed that CCTs may serve as valuable biomarkers for the diagnosis and targeted therapy of LUAD.

The CCT chaperonin and actin modulate the ER and RNA-binding protein condensation during oogenesis and maintain translational repression of maternal mRNA and oocyte quality.

The regulation of maternal mRNAs is essential for proper oogenesis, the production of viable gametes, and to avoid birth defects and infertility. Many oogenic RNA-binding proteins have been identified with roles in mRNA metabolism, some of which localize to dynamic ribonucleoprotein granules and others that appear dispersed. Here, we use a combination of in vitro condensation assays and the in vivo Caenorhabditis elegans oogenesis model to characterize the properties of the conserved KH-domain MEX-3 protein and to identify novel regulators of MEX-3 and three other translational regulators. We demonstrate that MEX-3 undergoes phase separation and appears to have intrinsic gel-like properties in vitro. We also identify novel roles for the chaperonin-containing tailless complex polypeptide 1 (CCT) chaperonin and actin in preventing ectopic RNA-binding protein condensates in maturing oocytes that appear to be independent of MEX-3 folding. The CCT chaperonin and actin also oppose the expansion of endoplasmic reticulum sheets that may promote ectopic condensation of RNA-binding proteins. These novel regulators of condensation are also required for the translational repression of maternal mRNA which is essential for oocyte quality and fertility. The identification of this regulatory network may also have implications for understanding the role of hMex3 phase transitions in cancer.

CCT3/ACTN4/TFRC axis protects hepatocellular carcinoma cells from ferroptosis by inhibiting iron endocytosis.

Sorafenib is widely used in treating advanced hepatocellular carcinoma (HCC). However, its effectiveness in prolonging patient survival is limited by the development of drug resistance. To systematically investigate the resistance mechanisms of Sorafenib, an integrative analysis combining posttranslational modification (PTM) omics and CRISPR/Cas9 knockout library screening was conducted. This analysis identified ubiquitination at lysine 21 (K21) on chaperonin-containing TCP1 subunit 3 (CCT3) as being associated with Sorafenib resistance. Transcriptomic data from HCC patients treated with Sorafenib revealed that CCT3 expression was lower in responders compared to non-responders. Experimentally, inhibiting the expression of CCT3 sensitized HCC cells to Sorafenib and enhanced Sorafenib-induced ferroptosis. Additionally, CCT3 was found to interact with ACTN4, hindering the recycling of transferrin receptor protein 1 (TFRC) to the cell membrane, thus obstructing iron endocytosis. Mechanistically, the inhibition of ferroptosis by CCT3 depends on the deubiquitination of K6-linked non-degradative ubiquitination at its K21, which occurs upon Sorafenib treatment. Moreover, CCT3 knockdown enhanced the anti-tumor effects of Sorafenib in nude mice. In summary, we have identified a novel function of the chaperone protein. Targeting the CCT3/ACTN4/TFRC axis offers a promising strategy to enhance ferroptosis and overcome Sorafenib resistance in HCC.

TCP1 expression alters the ferroptosis sensitivity of diffuse large B-cell lymphoma subtypes by stabilising ACSL4 and influences patient prognosis.

Diffuse large B-cell lymphoma (DLBCL), an invasive lymphoma with substantial heterogeneity, can be mainly categorised into germinal centre B-cell-like (GCB) and non-GCB subtypes. DLBCL cells are highly susceptible to ferroptosis, which offers an effective avenue for treating recurrent and refractory DLBCL. Moreover, various heat shock proteins are involved in regulating the sensitivity of tumour cells to ferroptosis. Among these proteins, tailless complex polypeptide 1 (TCP1), a subunit of chaperonin-containing T-complex protein-1 (CCT), plays a role in tumour proliferation and survival. Therefore, we explored the role of TCP1 in different DLBCL subtypes, the sensitivity of GCB and non-GCB subtypes to the ferroptosis inducer RAS-selective lethal small molecule 3 (RSL3), and the underlying molecular mechanism. In GCB cells, TCP1 promoted RSL3-induced ferroptosis. Notably, TCP1 could bind with acyl-CoA synthetase long-chain family member 4 (ACSL4), a key enzyme regulating lipid composition and facilitating ferroptosis, to reduce its ubiquitination and degradation. This interaction activated the ACSL4/LPCAT3 signalling pathway and promoted ferroptosis in the GCB subtype. However, in the non-GCB subtype, TCP1 did not act as a positive regulator but served as a predictor of an unfavourable prognosis in patients with non-GCB. In conclusion, our results suggest that in DLBCL, high TCP1 expression enhances the sensitivity of GCB tumour cells to ferroptosis and serves as a marker of poor prognosis in patients with non-GCB DLBCL.

CCT6A promotes cell proliferation in colon cancer by targeting BIRC5 associated with p53 status.

Chaperonin-containing TCP1 (CCT) is a multi-subunit complex, known to participate the correct folding of many proteins. Currently, the mechanism underlying CCT subunits in cancer progression is incompletely understood. Based on data analysis, the expression of CCT subunit 6 A (CCT6A) is found higher than the other subunits of CCT and correlated with an unfavorable prognosis in colon cancer. Here, we find CCT6A silencing suppresses colon cancer proliferation and survival phenotype in vitro and in vivo. CCT6A plays a role in cellular process, including the cell cycle, p53, and apoptosis signaling pathways. Further investigations have shown direct binding between CCT6A and both Wtp53 and Mutp53, and BIRC5 is found to act downstream of CCT6A. The highlight is that CCT6A inhibition significantly reduces BIRC5 expression independent of Wtp53 levels in Wtp53 cells. Conversely, in Mutp53 cells, downregulation of BIRC5 by CCT6A inhibition mainly depends on Mutp53 levels. Additionally, combined CCT6A inhibition and Wtp53 overexpression in Mutp53 cell lines effectively suppresses cell proliferation. It is concluded CCT6A is a potential oncogene that influences BIRC5 through distinct pathways in Wtp53 and Mutp53 cells.

METTL14-mediated N6-methyladenosine modification of TCP1 mRNA promotes acute myeloid leukemia progression.

BACKGROUND: Acute myeloid leukemia (AML) is a prevalent hematologic malignancy characterized by a steady rise in morbidity and mortality rates over time. The upregulation of methyltransferase-like 14 (METTL14) expression in AML has been identified; however, its specific contributions to AML progression and underlying molecular mechanisms have yet to be elucidated. METHOD: METTL14-bound mRNAs were predicted using bioinformatics methods, analyzed, and screened to identify T-complex protein 1 (TCP1). The regulatory impact of METTL14 on TCP1 was observed. TCP1 expression in AML clinical samples was assessed using quantitative real-time PCR and western blot analysis. The involvement of TCP1 in AML malignant progression was assessed through in vitro and in vivo functional assays. The String database was utilized for predicting proteins that interact with TCP1, while western blot assays and immunoprecipitation were employed to validate the associated signaling pathways. RESULTS: METTL14 overexpression upregulates TCP1 expression in AML cells. AML patients exhibit high levels of TCP1 expression. Elevated TCP1 levels in HL60 and U937 cells in vitro lead to increased proliferation, migration, invasion, and inhibition of apoptosis, while in vivo, it accelerates AML proliferation and tumorigenesis. Mechanistically, METTL14 modulates AML progression by influencing TCP1 transcript stability via m6A methylation, thereby regulating TCP1 expression. Additionally, PPP2R2C potentially serves as a crucial functional target of TCP1 implicated in the malignant progression of AML. CONCLUSION: Upregulation of TCP1 expression in AML through METTL14-mediated m6A modification accelerates the malignant progression of the disease. Therefore, targeting the m6A modification of TCP1 could be a potential therapeutic strategy to enhance the treatment of AML.

Compound heterozygous mutations in a mouse model of Leber congenital amaurosis reveal the role of CCT2 in photoreceptor maintenance.

TRiC/CCT is a chaperonin complex required for the folding of cytoplasmic proteins. Although mutations in each subunit of TRiC/CCT are associated with various human neurodegenerative diseases, their impact in mammalian models has not yet been examined. A compound heterozygous mutation in CCT2 (p.[Thr400Pro]; p.[Arg516His]) is causal for Leber congenital amaurosis. Here, we generate mice carrying each mutation and show that Arg516His (R516H) homozygosity causes photoreceptor degeneration accompanied by a significant depletion of TRiC/CCT substrate proteins in the retina. In contrast, Thr400Pro (T400P) homozygosity results in embryonic lethality, and the compound heterozygous mutant (T400P/R516H) mouse showed aberrant cone cell lamination and died 2 weeks after birth. Finally, CCDC181 is identified as a interacting protein for CCTß protein, and its localization to photoreceptor connecting cilia is compromised in the mutant mouse. Our results demonstrate the distinct impact of each mutation in vivo and suggest a requirement for CCTß in ciliary maintenance.

Epsilon subunit of T-complex protein-1 from Leishmania donovani: A tetrameric chaperonin.

The cytosolic T-complex protein-1 ring complex (TRiC), also referred as chaperonin containing TCP-1(CCT), comprising eight different subunits stacked in double toroidal rings, binds to around 10 % of newly synthesized polypeptides and facilitates their folding in ATP dependent manner. In Leishmania, among five subunits of TCP1 complex, identified either by transcriptome or by proteome analysis, only LdTCP1γ has been well characterized. It forms biologically active homo-oligomeric complex and plays role in protein folding and parasite survival. Lack of information regarding rest of the TCP1 subunits and its structural configuration laid down the necessity to study individual subunits and their role in parasite pathogenicity. The present study involves the cloning, expression and biochemical characterization of TCP1ε subunit (LdTCP1ε) of Leishmania donovani, the causative agent of visceral leishmaniasis. LdTCP1ε exhibited significant difference in primary structure as compared to LdTCP1γ and was evolutionary close to LdTCP1 zeta subunit. Recombinant protein (rLdTCP1ε) exhibited two major bands of 132 kDa and 240 kDa on native-PAGE that corresponds to the dimeric and tetrameric assembly of the epsilon subunit, which showed the chaperonin activity (ATPase and luciferase refolding activity). LdTCP1ε also displayed an increased expression upto 2.7- and 1.8-fold in the late log phase and stationary phase promastigotes and exhibited majorly vesicular localization. The study, thus for the first time, provides an insight for the presence of highly diverge but functionally active dimeric/tetrameric TCP1 epsilon subunit in Leishmania parasite.

The CCTδ subunit of the molecular chaperone CCT is required for correct localisation of p150Glued to spindle poles during mitosis.

Chaperonin Containing Tailless complex polypeptide 1 (CCT) is a molecular chaperone composed of eight distinct subunits that can exist as individual monomers or as components of a double oligomeric ring, which is essential for the folding of actin and tubulin and other substrates. Here we assess the role of CCT subunits in the context of cell cycle progression by individual subunit depletions upon siRNA treatment in mammalian cells. The depletion of individual CCT subunits leads to variation in the distribution of cell cycle phases and changes in mitotic index. Mitotic defects, such as unaligned chromosomes occur when CCTδ is depleted, concurrent with a reduction in spindle pole-localised p150Glued, a component of the dynactin complex and a binding partner of monomeric CCTδ. In CCTδ-depleted cells, changes in the elution profile of p150Glued are observed consistent with altered conformations and or assembly states with the dynactin complex. Addition of monomeric CCTδ, in the form of GFP-CCTδ, restores correct p150Glued localisation to the spindle poles and rescues the mitotic segregation defects that occur when CCTδ is depleted. This study demonstrates a requirement for CCTδ in its monomeric form for correct chromosome segregation via a mechanism that promotes the correct localisation of p150Glued, thus revealing further complexities to the interplay between CCT, tubulin folding and microtubule dynamics.

Targeting the molecular chaperone CCT2 inhibits GBM progression by influencing KRAS stability.

Proper protein folding relies on the assistance of molecular chaperones post-translation. Dysfunctions in chaperones can cause diseases associated with protein misfolding, including cancer. While previous studies have identified CCT2 as a chaperone subunit and an autophagy receptor, its specific involvement in glioblastoma remains unknown. Here, we identified CCT2 promote glioblastoma progression. Using approaches of coimmunoprecipitation, mass spectrometry and surface plasmon resonance, we found CCT2 directly bound to KRAS leading to increased stability and upregulated downstream signaling of KRAS. Interestingly, we found that dihydroartemisinin, a derivative of artemisinin, exhibited therapeutic effects in a glioblastoma animal model. We further demonstrated direct binding between dihydroartemisinin and CCT2. Treatment with dihydroartemisinin resulted in decreased KRAS expression and downstream signaling. Highlighting the significance of CCT2, CCT2 overexpression rescued the inhibitory effect of dihydroartemisinin on glioblastoma. In conclusion, the study demonstrates that CCT2 promotes glioblastoma progression by directly binding to and enhancing the stability of the KRAS protein. Additionally, dihydroartemisinin inhibits glioblastoma by targeting the CCT2 and the following KRAS signaling. Our findings overcome the challenge posed by the undruggable nature of KRAS and offer potential therapeutic strategies for glioblastoma treatment.

Dysfunction of CCT3-associated network signals for the critical state during progression of hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common malignant tumors and is a serious threat to human health; thus, early diagnosis and adequate treatment are essential. However, there are still great challenges in identifying the tipping point and detecting early warning signals of early HCC. In this study, we aimed to identify the tipping point (critical state) of and key molecules involved in hepatocarcinogenesis based on time series transcriptome expression data of HCC patients. The phase from veHCC (very early HCC) to eHCC (early HCC) was identified as the critical state in HCC progression, with 143 genes identified as key candidate molecules by combining the DDRTree (dimensionality reduction via graph structure learning) and DNB (dynamic network biomarker) methods. Then, we ranked the candidate genes to verify their mRNA levels using the diethylnitrosamine (DEN)-induced HCC mouse model and identified five early warning signals, namely, CCT3, DSTYK, EIF3E, IARS2 and TXNRD1; these signals can be regarded as the potential early warning signals for the critical state of HCC. We identified CCT3 as an independent prognostic factor for HCC, and functions of CCT3 involving in the "MYCtargets_V1" and "E2F-Targets" are closely related to the progression of HCC. The predictive method combining the DDRTree and DNB methods can not only identify the key critical state before cancer but also determine candidate molecules of critical state, thus providing new insight into the early diagnosis and preemptive treatment of HCC.

LINC01234 promoted malignant behaviors of breast cancer cells via hsa-miR-30c-2-3p/CCT4/mTOR signaling pathway.

OBJECTIVE: Despite continuous progress in treatment, recurrence and metastasis limit further improvement in the prognosis of breast cancer (BC) patients. Our aim was to search for a crucial prognostic biomarker of BC. MATERIALS AND METHODS: Patient data were selected from The Cancer Genome Atlas (TCGA) and GTEx databases. Several online public databases, including Gene Expression Profiling Interactive Analysis (GEPIA), miRWalk, miRDB, and LncBase Predicted v.2, were used to identify potential upstream miRNAs and lncRNAs. These findings were validated through in vitro experiments. RESULTS: A total of 1, 097 invasive BC samples and 572 normal breast tissues (including 113 samples from TCGA and 459 samples from GTEx) were collected for the study. CCT4 was not only significantly overexpressed in BC compared with normal breast tissues but also had important prognostic significance (P < 0.001). By intersecting miRWalk and miRDB and conducting correlation analysis, hsa-miR-30c-2-3p was identified as the most probable upstream miRNA of CCT4. Following an extensive assessment that included survival analysis, correlation analysis, and common binding-site prediction, LINC01234 was chosen as the most likely upstream lncRNA. In vitro experiments showed that LINC01234-siRNA inhibited the proliferation, invasion, and migration abilities of BC cells. Western blot analysis further confirmed that LINC01234 promoted malignant behaviors of BC cells via the CCT4/mTOR signaling pathway. CONCLUSION: The LINC01234/hsa-miR-30c-2-3p/CCT4/mTOR axis was identified as a potential ceRNA regulatory mechanism in BC. These findings established the foundation for systematically unveiling the pathological mechanisms of BC and provided new insights for targeted therapy of BC patients.

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.

Circular RNA CCT3 is a unique molecular marker in bladder cancer.

This study surveyed circular RNA CCT3 in bladder cancer (BCa). We recruited 85 BCa patients and 40 normal controls (Normal) and collected clinical specimens for analysis. circRNA CCT3 expression was analyzed by RT-qPCR, diagnostic accuracy was calculated by ROC curves, and survival outcomes were evaluated by survival curves. CircRNA CCT3 was overexpressed or knocked down in cells, thereafter to observe the changes in cell malignant phenotypes. The downstream molecules of circRNA CCT3 were detected. Our data suggest that circRNA CCT3 was upregulated in human BCa and was associated with poor survival outcomes of BCa patients. In cell experiments, overexpressing circRNA CCT3 promoted BCa cell malignancy, whereas silencing circRNA CCT3 did the opposite. In addition, circRNA CCT3 modulated PP2A expression by miR-135a-5p. This study demonstrates that circRNA CCT3 is a diagnostic and prognostic biomarker in BCa patients and is a tumor promoter in BCa.

A potential tumor marker: Chaperonin containing TCP­1 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 TCP­1 (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 cancer­related 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.

CCT3 as a Diagnostic and Prognostic Biomarker in Cervical Cancer.

The chaperonin-containing TCP1 complex subunit 3 (CCT3) has been reported to be involved in the development and prognosis of many tumors, including cervical cancer (CC). This study aimed to analyze the expression and prognostic value of CCT3 in CC by bioinformatics and retrospective study. CCT3 gene expression profiles and clinical information in CC were downloaded from the cancer genome atlas (TCGA) and gene expression omnibus (GEO) databases. CCT3 expression was verified by quantitative real-time polymerase chain reaction (RT-qPCR), Western blot, and immunohistochemistry (IHC). Logistic regression and chi-square testing were used to analyze the relationship between CCT3 expression and the clinical characteristics of CC. Kaplan-Meier and Cox analyses were used to evaluate whether CCT3 affects the prognosis of CC. Nomogram and calibration curves were used to test the predictive value of CCT3. The expression of CCT3 in CC tissues was significantly upregulated compared with that in adjacent benign tissues, and was related to HPV16/18 infection, grade, and positive lymph nodes. High expression of CCT3 is associated with poor prognosis of CC and can be used as an independent risk factor for CC. The prognostic model based on CCT3 and CC clinical features has good predictive ability. CCT3 is overexpressed in CC, which is related to poor prognosis and expected to become a biomarker for CC.

Single-Cell Transcriptome Analysis Revealed Heterogeneity and Identified Novel Therapeutic Targets for Breast Cancer Subtypes.

Breast cancer (BC) is a heterogeneous disease, which is primarily classified according to hormone receptors and HER2 expression. Despite the many advances in BC diagnosis and management, the identification of novel actionable therapeutic targets expressed by cancerous cells has always been a daunting task due to the large heterogeneity of the disease and the presence of non-cancerous cells (i.e., immune cells and stromal cells) within the tumor microenvironment. In the current study, we employed computational algorithms to decipher the cellular composition of estrogen receptor-positive (ER+), HER2+, ER+HER2+, and triple-negative BC (TNBC) subtypes from a total of 49,899 single cells' publicly available transcriptomic data derived from 26 BC patients. Restricting the analysis to EPCAM+Lin- tumor epithelial cells, we identified the enriched gene sets in each BC molecular subtype. Integration of single-cell transcriptomic with CRISPR-Cas9 functional screen data identified 13 potential therapeutic targets for ER+, 44 potential therapeutic targets for HER2+, and 29 potential therapeutic targets for TNBC. Interestingly, several of the identified therapeutic targets outperformed the current standard of care for each BC subtype. Given the aggressive nature and lack of targeted therapies for TNBC, elevated expression of ENO1, FDPS, CCT6A, TUBB2A, and PGK1 predicted worse relapse-free survival (RFS) in basal BC (n = 442), while elevated expression of ENO1, FDPS, CCT6A, and PGK1 was observed in the most aggressive BLIS TNBC subtype. Mechanistically, targeted depletion of ENO1 and FDPS halted TNBC cell proliferation, colony formation, and organoid tumor growth under 3-dimensional conditions and increased cell death, suggesting their potential use as novel therapeutic targets for TNBC. Differential expression and gene set enrichment analysis in TNBC revealed enrichment in the cycle and mitosis functional categories in FDPShigh, while ENO1high was associated with numerous functional categories, including cell cycle, glycolysis, and ATP metabolic processes. Taken together, our data are the first to unravel the unique gene signatures and to identify novel dependencies and therapeutic vulnerabilities for each BC molecular subtype, thus setting the foundation for the future development of more effective targeted therapies for BC.