A potential prognostic biomarker SPC24 promotes tumorigenesis and metastasis in lung cancer

Coregulation of NDC80 Complex Subunits Determines the Fidelity of the Spindle-Assembly Checkpoint and Mitosis

NDC80 complex (NDC80C) is composed of four subunits (SPC24, SPC25, NDC80, and NUF2) and is vital for kinetochore-microtubule (KT-MT) attachment during mitosis. Paradoxically, NDC80C also functions in the activation of the spindle-assembly checkpoint (SAC). This raises an interesting question regarding how mitosis is regulated when NDC80C levels are compromised. Using a degron-mediated depletion system, we found that acute silencing of SPC24 triggered a transient mitotic arrest followed by mitotic slippage. SPC24-deficient cells were unable to sustain SAC activation despite the loss of KT-MT interaction. Intriguingly, our results revealed that other subunits of the NDC80C were co-downregulated with SPC24 at a posttranslational level. Silencing any individual subunit of NDC80C likewise reduced the expression of the entire complex. We found that the SPC24-SPC25 and NDC80-NUF2 subcomplexes could be individually stabilized using ectopically expressed subunits. The synergism of SPC24 downregulation with drugs that promote either mitotic arrest or mitotic slippage further underscored the dual roles of NDC80C in KT-MT interaction and SAC maintenance. The tight coordinated regulation of NDC80C subunits suggests that targeting individual subunits could disrupt mitotic progression and provide new avenues for therapeutic intervention.

IMPLICATIONS

These results highlight the tight coordinated regulation of NDC80C subunits and their potential as targets for antimitotic therapies.

Cell Cycle-Related Gene SPC24: A Novel Potential Diagnostic and Prognostic Biomarker for Laryngeal Squamous Cell Cancer

Laryngeal squamous cell cancer (LSCC) is a common malignant tumor with a high degree of malignancy, and its etiology remains unclear. Therefore, screening potential biomarkers is necessary to facilitate the treatment and diagnosis of LSCC. Robust rank aggregation (RRA) analysis was used to integrate two gene expression datasets of LSCC patients from the Gene Expression Omnibus (GEO) database and identify differentially expressed genes (DEGs) between LSCC and nonneoplastic tissues. A gene coexpression network was constructed using weighted gene correlation network analysis (WGCNA) to explore potential associations between the module genes and clinical features of LSCC. Combining differential gene expression analysis and survival analysis, we screened potential hub genes, including CDK1, SPC24, HOXB7, and SELENBP1. Subsequently, western blotting and immunohistochemistry were used to test the protein levels in clinical specimens to verify our findings. Finally, four candidate diagnostic and prognostic biomarkers (CDK1, SPC24, HOXB7, and SELENBP1) were identified. We propose, for the first time, that SPC24 is a gene that may associate with LSCC malignancy and is a novel therapeutic target. These findings may provide important mechanistic insight of LSCC.

Spindle pole body component 24 homolog potentiates tumor progression via regulation of SRY-box transcription factor 2 in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is the most common pathological subtype of human kidney cancer with a high probability of metastasis. To understand the molecular processing essential for ccRCC tumorigenicity, we conducted an integrative in silico analysis of The Cancer Genome Atlas (TCGA) ccRCC dataset and clustered randomly interspersed short palindromic repeats (CRISPR) screening dataset of ccRCC cell lines from Depmap. We identified spindle pole body component 24 homolog (SPC24) as an essential gene for ccRCC cell lines with prognostic significance in the TCGA database. Targeting SPC24 by CRISPR/Cas9-mediated gene knockout attenuated ccRCC proliferation, metastasis, and in vivo tumor growth. Furthermore, we found that SPC24 regulates metastasis genes expression in a SRY-box transcription factor 2 (SOX2)-dependent manner. The anti-proliferative effects of SPC24 knockout were strengthened with SOX2 knockdown. Collectively, our findings suggest SPC24 has a pivotal function in promoting ccRCC progression, providing a new insight for the treatment of ccRCC.

Bioinformatics Analysis of Prognostic Value of SPC24 in ccRCC and Pan-Cancer

Purpose

Clear cell renal cell carcinoma (ccRCC) is one of the most common diseases in the world, with high morbidity and mortality. Recent studies have revealed the important role of SPC24, a subunit of the Ndc80 complex, in the occurrence and development of carcinoma. However, the latent effect of SPC24 in the progress of ccRCC remains to be further explored. The intent of this research is to investigate whether SPC24 can be used as an index to predict the progression of ccRCC and to explore its relationship with the immune microenvironment and pan-cancer.

Materials and Methods

Based on data from public databases, we determined the expression level and clinical value of SPC24 in ccRCC and human pan-cancer. RT-qPCR analysis was carried out to detect the expression level of SPC24 in the OSRC/786O (human ccRCC cells) cell lines and HK2 (human normal kidney cells) cell line. The signal transduction pathways activated by different levels of SPC24 expression were explored by Gene Set Enrichment Analysis (GSEA), and the CIBERSORT algorithm was applied to analyze the relationship between infiltrating immune cells and SPC24 expression in ccRCC and pan-cancer tissues.

Results

SPC24 is overexpressed in ccRCC and several types of tumors, which is associated with poor prognosis. GSEA and CIBERSORT algorithms suggested that the high expression group of SPC24 enriched various pathways including immune-related pathways, and the several infiltrated immunocytes were related to the expression of SPC24.

Conclusion

Our study revealed that SPC24 is a prognostic factor in ccRCC related to immunomodulation and has generalized value in pan-cancer.

Interferon Regulatory Factor 2 (IRF2) Inhibits the Invasion and Migration of Renal Clear Cell Carcinoma Cells by Downregulation of Spindle Pole Body Component 24 (SPC24)

It has been reported that the increased expression of SPC24 (spindle pole body component 24) was involved in the initiation and development of various cancers. However, the role of SPC24 in ccRCC (clear cell renal cell carcinoma) remains largely unknown. In the present study, the changes and correlation of SPC24 and IRF2 (interferon regulatory factor 2) with ccRCC were evaluated by using GEPIA, TCGA and GTEx database. Then the involvement of SPC24 and IRF2 in invasion and migration was investigated in CaKi-1 cells, a human renal adenocarcinoma cell line. The bioinformatics assay revealed that the expression of SPC24 and IRF2 in kidney tissue of patients with renal clear cell cancer was significantly increased, and the expression of SPC24 and IRF2 in kidney tissue was positively and negatively related to cancer phase and survival rate in patients with ccRCC respectively. Notably, in vitro experimental study demonstrated that SPC25 promoted the invasion and migration of CaKi-1 cells, a human renal adenocarcinoma cell line. Furthermore, IRF2 shows potential binding site with SPC24 promoter, IRF2 overexpression significantly decreased SPC24 mRNA level, whereas inhibition of IRF2 with specific small hairpin RNA (shRNA) significantly increased SPC24 mRNA level. Functionally, inhibition of SPC24 with specific shRNA reversed the stimulatory effect of IRF2 shRNA on the invasion and migration of cells, whereas SPC24 over-expression reversed the inhibitory effect of IRF2 overexpression on the invasion and migration of cells. Finally, ChIP (chromatin immunoprecipitation) assay shows that IRF2 could directly bind with SPC24 promoter. In conclusion, these results demonstrated that IRF2/SPC24 signaling pathway contributes to the increased invasion and migration in ccRCC.

Increased SPC24 in prostatic diseases and diagnostic value of SPC24 and its interacting partners in prostate cancer

SPC24 is a crucial component of the mitotic checkpoint machinery in tumorigenesis. High levels of SPC24 have been found in various cancers, including breast cancer, lung cancer, liver cancer, osteosarcoma and thyroid cancer. However, to the best of our knowledge, the impact of SPC24 on prostate cancer (PCa) and other prostate diseases remains unclear. In the present study expression of global SPC24 messenger RNA (mRNA) was assessed in a subset of patients with PCa included in The Cancer Genome Atlas (TCGA) database. Increased levels of SPC24 expression were found in PCa patients >60 years old compared to patients <60 and increased SPC24 expression was also associated with higher levels of prostate specific antigen (P<0.05) and lymph node metastasis (P<0.05). Higher levels of SPC24 expression were associated with negative outcomes in PCa patients (P<0.05). Furthermore, in Chinese patients with prostatitis, benign prostatic hypertrophy (BPH) and PCa, SPC24 was expressed at significantly higher levels than that in adjacent/normal tissues, as assessed by reverse transcription-quantitative polymerase chain reaction, immunohistochemistry and western blotting. High expression of SPC24 was associated with high Gleason stages (IV and V; P<0.05). Further analysis, based on Gene Ontology and pathway functional enrichment analysis, suggested that nuclear division cycle 80 (NDC80), an SPC24 protein interaction partner, and mitotic spindle checkpoint serine/threonine-protein kinase BUB1 (BUB1), a core subunit of the spindle assembly checkpoint, may be associated with SPC24 in PCa development. Finally, using binary logistic regression, algorithms combining the receiver operating characteristic between SPC24 and BUB1 or NDC80 indicated that a combination of these markers may provide better PCa diagnosis ability than other PCa diagnosis markers. Taken together, these findings suggest that SPC24 may be a promising prostate disease biomarker.

hsa-miR-7-5p suppresses proliferation, migration and promotes apoptosis in hepatocellular carcinoma cell lines by inhibiting SPC24 expression

Emerging evidence suggests that microRNAs (miRNAs) participate in hepatocellular carcinoma (HCC) progression. Nevertheless, the mechanism of miR-7-5p in HCC cells has not been researched. In the research, the underlying biological function of miR-7-5p and SPC24 in HCC was explored. qRT-PCR was performed to measure the miR-7-5p and SPC24 level in HCC tissues and cells. The effect of miR-7-5p on HCC progression was detected by performing CCK-8, BrdU, and transwell assay. The relationship between miR-7-5p and SPC24 was determined using luciferase and RNA pull-down assays. Our findings showed that miR-7-5p was downregulated in HCC whereas SPC24 was upregulated in HCC. It was also showed that miR-7-5p upregulation restricted malignant behaviors of HCC cells, but this inhibitory effect of miR-7-5p could be relieved by its target gene SPC24. In conclusion, this research suggested that by inhibiting SPC24, miR-7-5p could act as a tumor inhibitory factor in HCC.

Identification of potential and novel target genes in pituitary prolactinoma by bioinformatics analysis

Pituitary prolactinoma is one of the most complicated and fatally pathogenic pituitary adenomas. Therefore, there is an urgent need to improve our understanding of the underlying molecular mechanism that drives the initiation, progression, and metastasis of pituitary prolactinoma. The aim of the present study was to identify the key genes and signaling pathways associated with pituitary prolactinoma using bioinformatics analysis. Transcriptome microarray dataset GSE119063 was downloaded from Gene Expression Omnibus (GEO) database. Limma package in R software was used to screen DEGs. Pathway and Gene ontology (GO) enrichment analysis were conducted to identify the biological role of DEGs. A protein-protein interaction (PPI) network was constructed and analyzed by using HIPPIE database and Cytoscape software. Module analyses was performed. In addition, a target gene-miRNA regulatory network and target gene-TF regulatory network were constructed by using NetworkAnalyst and Cytoscape software. Finally, validation of hub genes by receiver operating characteristic (ROC) curve analysis. A total of 989 DEGs were identified, including 461 up regulated genes and 528 down regulated genes. Pathway enrichment analysis showed that the DEGs were significantly enriched in the retinoate biosynthesis II, signaling pathways regulating pluripotency of stem cells, ALK2 signaling events, vitamin D3 biosynthesis, cell cycle and aurora B signaling. Gene Ontology (GO) enrichment analysis showed that the DEGs were significantly enriched in the sensory organ morphogenesis, extracellular matrix, hormone activity, nuclear division, condensed chromosome and microtubule binding. In the PPI network and modules, SOX2, PRSS45, CLTC, PLK1, B4GALT6, RUNX1 and GTSE1 were considered as hub genes. In the target gene-miRNA regulatory network and target gene-TF regulatory network, LINC00598, SOX4, IRX1 and UNC13A were considered as hub genes. Using integrated bioinformatics analysis, we identified candidate genes in pituitary prolactinoma, which might improve our understanding of the molecular mechanisms of pituitary prolactinoma.

Progression Risk Assessment of Post-surgical Papillary Thyroid Carcinoma Based on Circular RNA-Associated Competing Endogenous RNA Mechanisms

Background: Accurate risk assessment of post-surgical progression in papillary thyroid carcinoma (PTC) patients is critical. Exploring key differentially expressed mRNAs (DE-mRNAs) regulated by differentially expressed circular RNAs (circRNAs) via the ceRNA mechanism could help establish a novel assessment tool. Methods: ceRNA network was established based on differentially expressed RNAs and correlation analysis. DE-mRNAs within the ceRNA network associated with progression-free interval (PFI) of PTC were identified to construct a prognostic ceRNA regulatory subnetwork. least absolute shrinkage and selection operator (LASSO)-Cox regression was applied to identify hub DE-mRNAs and establish a novel DE-mRNA signature in predicting PFI of PTC. Results: Six hub DE-mRNAs, namely, CLCNKB, FXBO27, FXYD6, RIMS2, SPC24, and CDKN2A, were identified to be most significantly related to the PFI of PTC, and a prognostic DE-mRNA signature was proposed. A nomogram incorporating the DE-mRNA signature and clinical parameters was established to improve the progression risk assessment in post-surgical PTC, which was superior to the American Thyroid Association risk stratification system and distant Metastasis, patient Age, Completeness of resection, local Invasion, and tumor Size (MACIS) score American Joint Committee on Cancer staging system. Conclusions: Based on the circRNA-associated ceRNA RNA mechanism, a DE-mRNA signature and prognostic nomogram was established, which may improve the progression risk assessment in post-surgical PTC.

SPC25 overexpression promotes tumor proliferation and is prognostic of poor survival in hepatocellular carcinoma

Background: The nuclear division cycle 80 (NDC80) complex assures proper chromosome segregation during the cell cycle progression. SPC25 is a crucial component of NDC80, and its role in hepatocellular carcinoma (HCC) has been explored recently. This study characterized the differential expression of SPC25 in HCC patients of different races and HBV infection status.

Methods: Expression patterns of SPC25 were evaluated in TCGA and Chinese HCC patients. Kaplan-Meier analysis was applied to examine the predictive value of SPC25. In vitro and in vivo functional assays were conducted to explore the role of SPC25 in HCC. Bioinformatics methods were applied to investigate the regulatory mechanisms of SPC25.

Findings: The mRNA levels of SPC25 were up-regulated in HCC. SPC25 has a significantly higher transcriptional level in Asian patients than Caucasian patients. SPC25 promoted HCC cell proliferation in vitro and tumor growth in vivo by accelerating the cell cycle. We identified transcription factors, miRNAs, and immune cells that may interact with SPC25.

Interpretation: The findings suggest that increased expression of SPC25 is associated with poor prognosis of HCC and enhances the proliferative capacity of HCC cells. SPC25 could serve as a valuable prognostic marker and a novel treatment target for HCC.

Potential therapeutic targets of the nuclear division cycle 80 (NDC80) complexes genes in lung adenocarcinoma

Background: Lung cancer is the most common cancer worldwide, both in terms of the incidence and mortality. NDC80 complex comprising of NDC80, NUF2, SPC24, and SPC25 is a heterotetrameric protein complex located in the outer layer of the kinetochore and plays a critical role in mitosis. This study focuses on the effects of NDC80 complex genes on clinical features and prognosis in lung adenocarcinoma (LUAD). Materials and methods: Expression of NDC80 complex in LUAD and related clinical information was extracted from the TCGA website. NDC80 complex gene functional analysis and correlation analysis was conducted by using DAVID, BiNGO, Gene MANIA, STRING and GSEA. Survival probability was predicted by nomogram. Statistical analysis was used to predict NDC80 complex gene expression on clinical features and prognosis in patients with LUAD. Results: Expression of NDC80, NUF2, SPC24 and SPC25 was significantly elevated in LUAD tumors compared with normal tissues (P < 0.05). These genes showed diagnostic values for LUAD (P < 0.001 for each; area under the curve (AUC), 0.958, 0.968, 0.951, and 0.932 respectively); combinatorial analysis of these genes was more advantageous than single analysis alone (P < 0.001; AUC > 0.900 for each). Expression of both NDC80 and SPC25 correlated with the prognosis of LUAD (P < 0.001; AUC > 0.600 for each). Higher expression of NDC80, NUF2, SPC24 and SPC25 was associated with low overall survival (OS) in univariate analysis. Higher expression of NDC80 and SPC25 was associated with low OS in multivariate analysis. High expression of NDC80 combined with high expression of SPC25 was predictive of poor OS in LUAD in joint analysis. Conclusion: NDC80 complex gene might be an early indicator of diagnosis and prognosis of LUAD. The combined detection of NDC80, NUF2, SPC24 and SPC25 may become a new research direction in LUAD diagnosis and a new target for tumor targeted gene therapy.

Targeting CDK12-mediated transcription regulation in anaplastic thyroid carcinoma

Anaplastic thyroid carcinoma (ATC) is the most aggressive type of thyroid cancer, with no effective treatment available. Identification of new anti-ATC drugs represents an urgent need. In this study, we find that ATC cells are highly sensitive to THZ531, a potent inhibitor of the transcriptional cyclin-dependent kinase (CDK), CDK12. Cell-based assays demonstrate that CDK12 inhibition significantly impedes cell cycle progression, induces apoptotic cell death, and impairs colony formation in ATC cells. THZ531 causes a loss of elongating RNA polymerase II and suppresses gene expression in ATC cells. An integrative analysis of gene expression profiles and super-enhancer landscape, combining with functional assays, leads to the discovery of two new ATC cancer genes, ZC3H4 and NEMP1. Furthermore, CDK12 inhibition enhances the sensitivity of ATC cells to doxorubicin-mediated chemotherapy. Thus, these findings indicate that CDK12 is a potential therapeutic target for ATC treatment and its inhibition may help to overcome the chemoresistance in patients with ATC.

Long non-coding RNA CHRF promotes proliferation and mesenchymal transition (EMT) in prostate cancer cell line PC3 requiring up-regulating microRNA-10b

Despite the advance of diagnosis and treatment for prostate cancer, the prognosis of metastatic prostate cancer is poor. We aimed to explore the functional role of long non-coding RNA cardiac hypertrophy-related factor (lncRNA CHRF) in prostate cancer cells (PC3) as well as the molecular mechanisms. LncRNA CHRF silence repressed cell number (%), down-regulated expression of cyclinD1, CDK4 and CDK6, and promoted apoptosis along with activation of the casapse-3 and caspase-9. LncRNA CHRF promoted mesenchymal transition (EMT), showing down-regulation of E-cadherin and up-regulation of N-cadherin, vimentin and ZEB1. Afterwards, we found miR-10b expression was positively correlated with lncRNA CHRF expression, and miR-10b inhibition could reverse the effects of lncRNA CHRF on PC3 and LNCaP cell proliferation and EMT. Finally, lncRNA CHRF was found to activate the GSK3β/AKT and NF-κB pathways via up-regulation of miR-10b. LncRNA CHRF silence repressed proliferation and EMT while promoted apoptosis in PC3 cells via positive regulation of miR-10b. The GSK3β/AKT and NF-κB pathways were activated by lncRNA CHRF, possibly through up-regulation of miR-10b.

Nuclear division cycle 80 complex is associated with malignancy and predicts poor survival of hepatocellular carcinoma

The NDC80 (nuclear division cycle 80) complex takes part in chromosome segregation by forming an outer kinetochore and providing a platform for the interaction between chromosomes and microtubules, thus impacting the progression of mitosis and the cell cycle. The clinical significance of its components, NDC80, nuf2, spc24, and spc25, were widely explored in various malignancies respectively, yet seldom were they studied from the perspective of a complex. This paper explores the clinical importance of the NDC80 kinetochore complex components in terms of their expression level, prognostic value, and therapeutic potential in HCC (hepatocellular carcinoma) patients. With the data from several paired HCC samples from Nanfang Hospital, HCC patients from the TCGA database and other cases from GSE89377, we analyzed the expression levels of the NDC80 complex components, NDC80/nuf2/spc24/spc25, along with the survival data as well as other clinical features using statistical methods and GSEA. The study found that a high expression of NDC80 complex predicts poor survival, and these components have the potential to be used as therapeutic targets.

KLF6-SV1 is a new prognostic biomarker in postoperative patients with non-small cell lung cancer

Objectives

Non-small cell lung cancer (NSCLC) is aggressive and associated with a poor prognosis. Recent studies have revealed that several genes are involved in the origin and progression of NSCLC. Kruppel-like factor 6 (KLF6) inactivation has been shown in some malignant tumors. KLF6-SV1, as one of the alternatively spliced KLF6 isoforms, has been found to be correlated with metastatic potential and poor survival in some cancers. The purpose of this study was to investigate the clinical and prognostic significance of KLF6-SV1 expression in NSCLC patients after curative resection.

Patients and methods

A total of 79 patients were enrolled in this study. Enumeration data were analyzed using the chi-squared test or Fisher’s exact probability test. Measurement data were represented as average±SD and t-test (homoscedasticity) or t’-test (homoscedasticity uneven). Univariate analysis was performed by modeling Kaplan–Meier survival curves. The log-rank test was used to calculate the survival rate. Multivariate analysis was carried out by the use of the Cox proportional hazard model.

Results

KLF6-SV1 expression was correlated with pN (P<0.05) and pTNM stage (P<0.05). The expression of KLF6-SV1 in the adenocarcinoma group was significantly higher than that in the squamous cell carcinoma group (P<0.05). The 5-year survival rate for 79 NSCLC patients was 40.5%, and it was significantly associated with differentiation (P<0.05), pN (P<0.01), pTNM stage (P<0.01) and high expression of KLF6-SV1 (P<0.01). Cox multivariate regression demonstrated that differentiation, pN and KLF6-SV1 expression were independent factors for the 5-year survival rate.

Conclusion

KLF6-SV1 expression in adenocarcinoma was significantly higher than that in the squamous cell carcinoma, and high expression of KLF6-SV1 was significantly associated with pN and pTNM stage and poor survival in NSCLC patients.

Role of miR-520b in non-small cell lung cancer

The aim of the present study was to investigate the expression of microRNA (miR)-520b in non-small cell lung cancer (NSCLC) and its biological functions. Reverse transcription-quantitative polymerase chain reaction was used to detect the expression of miR-520b in 52 cases of NSCLC tissues, and its associations with tumor clinical staging and lymph node metastasis were analyzed. miR-520b mimics was transfected into A549 and Calu-3 cells. Cell proliferation, cell cycle, and cell invasion and migration abilities were assessed via cell counting kit-8 assay, flow cytometry and Transwell chamber assay, respectively. Western blot analysis was performed to detected protein expression levels, and dual luciferase reporter assay was used to detect the gene interaction. miR-520b expression was significantly downregulated in NSCLC. The expression of miR-520b in tumor tissues at N1 stage was lower than that at the N0 stage. miR-520b expression was negatively associated with clinical TNM staging. Furthermore, miR-520b mimic transfection inhibited the proliferation and invasion and metastasis abilities of A549 and Calu-3 cells. The expression of Rab22A was downregulated in the miR-520b mimics-transfected cells, whereas E-cadherin expression was increased, and vimentin expression was downregulated. Dual luciferase reporter assay demonstrated that miR-520b directly targeted the expression of Rab22A. Furthermore, Rab22A reversal downregulated the inhibitory effect of miR-520b. miR-520b expression was downregulated in NSCLC, which was negatively correlated with lymph node metastasis and TNM staging. miR-520b targeted on Rab22A to work as a tumor suppressor, inhibiting tumor proliferation and metastasis.

Clinical and prognostic significance of signal transducer and activator of transcription 3 and mucin 1 in patients with non-small cell lung cancer following surgery

Signal transducer and activator of transcription 3 (STAT3) and mucin 1 (MUC1) are associated with development, progression and a poor prognosis in several types of cancer. The present study investigated the levels of STAT3 and MUC1 in patients with non-small cell lung cancer (NSCLC) following surgery. In total, 98 patients with NSCLC were enrolled into the study. STAT3, phosphorylated (p)-STAT3 and MUC1 expression in NSCLC specimens obtained from patients were investigated using immunohistochemical analysis. Enumeration results were analyzed using the χ² test or Fisher's exact probability test. Spearman's rank correlation was used to analyze correlations between STAT3, p-STAT3 and MUC1 expression. Univariate analysis was conducted using the Kaplan-Meier estimator curve method and Cox regression multivariate analysis was performed in order to determine prognostic factors. Results demonstrated that STAT3 and p-STAT3 expression was identified in 82 and 51 patients, respectively. Furthermore, the expression of MUC1 was identified in 61/98 cases (62.2%) and STAT3 expression was significantly associated with pathological tumor-node-metastasis stage (pTNM; P<0.01). p-STAT3 expression was associated with pathological type (P<0.01), pathological lymph nodes (pN; P<0.01) and pTNM (P<0.05). MUC1 expression was associated with pathological type (P<0.05), pathological tumor pT (P<0.05), pN (P<0.01) and pTNM (P<0.01). STAT3 expression was positively associated with p-STAT3 expression (P<0.05) and p-STAT3 expression was positively associated with MUC1 expression (P<0.01). Overall, the results identified that the 3-year survival rate was 56.1% and was significantly associated with the degree of differentiation (P<0.05), pT (P<0.01), pN (P<0.01), pTNM stage (P<0.01), p-STAT3 expression (P<0.01) and MUC1 expression (P<0.05). Results obtained from the Cox multivariate regression analysis demonstrated that pN and p-STAT3 expression were independent factors associated with the 3-year survival rate.