Expression of FXYD-3 is an Independent Prognostic Factor in Rectal Cancer Patients With Preoperative Radiotherapy

The roles of FXYD family members in ovarian cancer: an integrated analysis by mining TCGA and GEO databases and functional validations

BACKGROUND

The FXYD family of ion transport regulators have emerged as important modulators of cancer progression and metastasis. However, their expression and roles in ovarian cancer (OCa) have not been systematically investigated.

METHODS

The expression of FXYD genes in OCa was analyzed using data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO), as well as independent clinical samples. The prognostic values of FXYD genes were evaluated by Kaplan-Meier and Cox regression analysis. To explore potential mechanisms, bioinformatics approaches including Gene Ontology, KEGG pathway analysis, GSEA and drug sensitivity correlation analysis were performed. OCa cell lines overexpressing FXYD1, FXYD5 or FXYD7 were also generated and their impacts on proliferation, migration and invasion were assessed.

RESULTS

FXYD1 and FXYD6 were significantly downregulated while FXYD3, FXYD4 and FXYD5 were upregulated in OCa tissues compared to normal tissues. FXYD1, FXYD5 and FXYD7 were independent adverse prognostic factors for OCa patients. Pathway and drug correlation analysis revealed that FXYD1, FXYD5 and FXYD7 genes regulated diverse oncogenic signaling cascades and modulated the response to various chemotherapeutic agents. Overexpression of FXYD1, FXYD5 or FXYD7 enhanced OCa cell motility and invasiveness in vitro.

CONCLUSION

Our results demonstrate aberrant expression patterns, prognostic values, and oncogenic activities of FXYD genes in OCa. FXYD1, FXYD5 and FXYD7 may serve as biomarkers and therapeutic targets for this disease. Targeting FXYD-mediated signaling represents a promising therapeutic strategy against OCa.

FXYD3 Expression Predicts Poor Prognosis in Renal Cell Carcinoma with Immunosuppressive Tumor Microenvironment

Simple Summary

FXYD3 belongs to the protein-coding gene family associated with Na+/K+-ATPase enzymes and chloride ion channels. Recently, the biological role of FXYD3 has been reported in multiple cancers. Nevertheless, the prognostic value of FXYD3 expression has been undiscovered in clear renal cell carcinoma (KIRC). In this study, we assessed the datasets from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) dataset (GSE29609). We found the FXYD3 high KIRC patients had distinct clinical characteristics, including hypoxia and poor overall survival. Furthermore, the algorithms discovered that FXYD3 mRNA levels were associated with tumor purity, multiple types of the tumor infiltrating lymphocytes (TILs) and several genes related to T cell exhaustion. In conclusion, FXYD3 predicts a poor prognosis associated with hypoxia, pro-tumor TILs, and T cell exhaustion in KIRC.

Abstract

FXYD3 is a protein-coding gene, belonging to the FXYD protein family associated with Na+/K+-ATPase enzymes and chloride ion channels. Accumulating evidence suggests the biological role of FXYD3 in multiple cancers. However, the prognostic value of FXYD3 expression in clear renal cell carcinoma (KIRC) is unclear. Therefore, we evaluated the clinical data with tumor-infiltrating lymphocytes (TILs) and immunoinhibitory gene expression data using The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) dataset (GSE29609). First, the FXYD3 high KIRC patients had distinct clinical characteristics, including age, sex, disease stage, histological grade, and hypoxia-related gene expressions. Next, FXYD3 gene expression was correlated with poor overall survival in both TCGA and GSE29609 cohorts. The ESTIMATE algorithm revealed that higher FXYD3 mRNA levels were associated with increased infiltration of immune cells and tumor purity. Moreover, the FXYD3 high KIRC tissue harbored increased TILs such as B cells, CD8+ T cells, and M1 macrophage, whereas NK cells and neutrophils were decreased. In addition, we showed FXYD3 was co-expressed with several immunoinhibitory genes related to T cell exhaustion such as LGALS9, CTLA4, BTLA, PDCD1, and LAG3. In conclusion, FXYD3 is an unfavorable prognostic biomarker associated with hypoxia, pro-tumor TILs, and T cell exhaustion.

Downregulation of FXYD2 Is Associated with Poor Prognosis and Increased Regulatory T Cell Infiltration in Clear Cell Renal Cell Carcinoma

BACKGROUND

FXYD2, a gene coding for the γ subunit of Na⁺/K⁺-ATPase, was demonstrated to involve in carcinogenesis recently. However, the specific role of FXYD2 in clear cell renal cell carcinoma (ccRCC) remains unknown. The current study was conducted to investigate the expression, biological function, and potentially immune-related mechanisms of FXYD2 in ccRCC. Materials and methods. The data from TCGA-KIRC, ICGC, GEO, Oncomine, ArrayExpress, TIMER, HPA datasets, and our clinical samples were used to determine and validate the expression level, prognostic roles, and potentially immune-related mechanisms in ccRCC. Cell function assays were performed to investigate the biological role of FXYD2 in vitro.

RESULTS

FXYD2 was identified to be downregulated in ccRCC tissue compared to normal tissue, which was confirmed by our RT-PCR, WB, and IHC analyses. Kaplan-Meier survival analysis and Cox regression analysis suggested that downregulated FXYD2 could independently predict poor survival of ccRCC patients. Through the ESTIMATE algorithm, ssGSEA algorithm, CIBERSORT algorithm, TIMER database, and our laboratory experiment, FXYD2 was found to correlate with the immune landscape, especially regulatory T cells (Treg), in ccRCC. Gain-of-function experiment revealed that FXYD2 could restrain cell proliferation, migration, and invasion in vitro. Functional enrichment analysis illustrated that TGF-β-SMAD2/3, Notch, and PI3K-Akt-mTOR signaling pathways may be potential signaling pathways of FXYD2 in ccRCC.

CONCLUSIONS

Downregulation of FXYD2 is associated with ccRCC tumorigenesis, poor prognosis, and increased Treg infiltration in ccRCC, which may be related to TGF-β-SMAD2/3, Notch, and PI3K-Akt-mTOR signaling pathways. This will probably provide a novel prognostic marker and potential therapeutic target for ccRCC.

Expression mode and prognostic value of FXYD family members in colon cancer

The FXYD gene family comprises seven members that encode a class of small-membrane proteins characterized by an FXYD motif and interact with Na⁺/K⁺-ATPase. Until now, the expression patterns and prognostic roles of the FXYD family in colon cancer (CC) have not been systematically reported. Gene expression, methylation, clinicopathological features and the prognoses of CC patients were obtained from The Cancer Genome Atlas (TCGA) database. The expression feature and prognostic values of FXYD members were identified. Gene set enrichment analysis (GSEA) was performed to explore the potential mechanism underlying the function of the FXYD family in CC. Tumor Immune Estimation Resource (TIMER) and CIBERSORT analysis were used to assess the correlations between FXYD family members and tumor immune infiltrating cells (TIICs). FXYD family members were differentially expressed in CC except for FXYD2. FXYD2, FXYD3 and FXYD4 were revealed as independent prognostic factors for recurrence, while FXYD3 and FXYD7 were identified as prognostic factors for survival according to univariate and multivariate analyses with Cox regression. GSEA revealed that FXYD family members were involved in complicated biological functions underlying cancer progression. TIMER and CIBERSORT analyses showed significant associations between FXYD family genes and TIICs. The present study comprehensively revealed the expression mode and prognostic value of FXYD members in CC, providing insights for further study of the FXYD family as potential clinical biomarkers in CC.

Population-based study of effectiveness of neoadjuvant radiotherapy on survival in US rectal cancer patients according to age

Recent cancer researches pay more attention to younger patients due to the variable treatment response among different age groups. Here we investigated the effectiveness of neoadjuvant radiation on the survival of younger and older patients in stage II/III rectal cancer. Data was obtained from Surveillance, Epidemiology, and End Results (SEER) database (n = 12801). Propensity score matching was used to balance baseline covariates according to the status of neoadjuvant radiation. Our results showed that neoadjuvant radiation had better survival benefit (Log-rank P = 3.25e-06) and improved cancer-specific 3-year (87.6%; 95% CI: 86.4–88.7% vs. 84.1%; 95% CI: 82.8–85.3%) and 5-year survival rates (78.1%; 95% CI: 76.2–80.1% vs. 77%; 95% CI: 75.3–78.8%). In older groups (>50), neoadjuvant radiation was associated with survival benefits in stage II (HR: 0.741; 95% CI: 0.599–0.916; P = 5.80e-3) and stage III (HR: 0.656; 95% CI 0.564–0.764; P = 5.26e-08). Interestingly, neoadjuvant radiation did not increase survival rate in younger patients (< = 50) both in stage II (HR: 2.014; 95% CI: 0.9032–4.490; P = 0.087) and stage III (HR: 1.168; 95% CI: 0.829–1.646; P = 0.372). Additionally, neoadjuvant radiation significantly decreased the cancer-specific mortality in older patients, but increased mortality in younger patients. Our results provided new insights on the neoadjuvant radiation in rectal cancer, especially for the younger patients.

Special AT-rich sequence binding protein 1 expression correlates with response to preoperative radiotherapy and clinical outcome in rectal cancer

Our recent study showed the important role of special AT-rich sequence binding protein 1 (SATB1) in the progression of human rectal cancer. However, the value of SATB1 in response to radiotherapy (RT) for rectal cancer hasn't been reported so far. Here, SATB1 was determined using immunohistochemistry in normal mucosa, biopsy, primary cancer, and lymph node metastasis from 132 rectal cancer patients: 66 with and 66 without preoperative RT before surgery. The effect of SATB1 knockdown on radiosensitivity was assessed by proliferation-based assay and clonogenic assay. The results showed that SATB1 increased from normal mucosa to primary cancer, whereas it decreased from primary cancer to metastasis in non-RT patients. SATB1 decreased in primary cancers after RT. In RT patients, positive SATB1 was independently associated with decreased response to preoperative RT, early time to metastasis, and worse survival. SATB1 negatively correlated with ataxia telangiectasia mutated (ATM) and pRb2/p130, and positively with Ki-67 and Survivin in RT patients, and their potential interaction through different canonical pathways was identified in network ideogram. Taken together, our findings disclose for the first time that radiation decreases SATB1 expression and sensitizes cancer cells to confer clinical benefit of patients, suggesting that SATB1 is predictive of response to preoperative RT and clinical outcome in rectal cancer.

MicroRNA-143 is a putative predictive factor for the response to fluoropyrimidine-based chemotherapy in patients with metastatic colorectal cancer

Approximately half of the colorectal cancer (CRC) patients develop metastatic disease. Fluoropyrimidine-based chemotherapy forms the backbone of treatment in these patients. However, the response to this therapy varies between individuals. Therefore, an important challenge in CRC research is to identify biomarkers that are predictive of this response. In this study, we explored the potential of miRNAs, and the miRNA producing protein Dicer, as biomarkers that can predict chemo-sensitivity to fluoropyrimidine chemotherapy in patients with metastatic colorectal cancer (mCRC). We analyzed the levels of 22 miRNAs and the Dicer protein in primary tumors from patients with mCRC who were treated with first-line capecitabine monotherapy within the CAIRO trial of the Dutch Colorectal Cancer Group. Correlation between the expression status of miRNAs or Dicer in primary tumors and the progression free survival (PFS) were investigated. Patients with low expression of miR-143 in their primary tumor had increased median PFS compared to those with high expression of miR-143. Furthermore, FXYD3, an ion transport regulator and a putative target of miR-143, also showed an association with PFS. These findings warrant further studies to investigate the relationship between miR-143, FXYD3 and fluoropyrimidines, and the clinical utility of miR-143 as biomarker.

FXYD-3 expression in relation to local recurrence of rectal cancer

Purpose

In a previous study, the transmembrane protein FXYD-3 was suggested as a biomarker for a lower survival rate and reduced radiosensitivity in rectal cancer patients receiving preoperative radiotherapy. The purpose of preoperative irradiation in rectal cancer is to reduce local recurrence. The aim of this study was to investigate the potential role of FXYD-3 as a biomarker for increased risk for local recurrence of rectal cancer.

Materials and Methods

FXYD-3 expression was immunohistochemically examined in surgical specimens from a cohort of patients with rectal cancer who developed local recurrence (n = 48). The cohort was compared to a matched control group without recurrence (n = 81).

Results

Weak FXYD-3 expression was found in 106/129 (82%) of the rectal tumors and strong expression in 23/129 (18%). There was no difference in the expression of FXYD-3 between the patients with local recurrence and the control group. Furthermore there was no difference in FXYD-3 expression and time to diagnosis of local recurrence between patients who received preoperative radiotherapy and those without.

Conclusion

Previous findings indicated that FXYD-3 expression may be used as a marker of decreased sensitivity to radiotherapy or even overall survival. We were unable to confirm this in a cohort of rectal cancer patients who developed local recurrence.

Silencing overexpression of FXYD3 protein in breast cancer cells amplifies effects of doxorubicin and γ-radiation on Na(+)/K(+)-ATPase and cell survival

FXYD3, also known as mammary tumor protein 8, is overexpressed in several common cancers, including in many breast cancers. We examined if such overexpression might protect Na(+)/K(+)-ATPase and cancer cells against the high levels of oxidative stress characteristic of many tumors and often induced by cancer treatments. We measured FXYD3 expression, Na(+)/K(+)-ATPase activity and glutathionylation of the β1 subunit of Na(+)/K(+)-ATPase, a reversible oxidative modification that inhibits the ATPase, in MCF-7 and MDA-MB-468 cells. Expression of FXYD3 was suppressed by transfection with FXYD3 siRNA. A colorimetric end-point assay was used to estimate cell viability. Apoptosis was estimated by caspase 3/7 (DEVDase) activation using a Caspase fluorogenic substrate kit. Expression of FXYD3 in MCF-7 breast cancer cells was ~eightfold and ~twofold higher than in non-cancer MCF-10A cells and MDA-MB-468 cancer cells, respectively. A ~50 % reduction in FXYD3 expression increased glutathionylation of the β1 Na(+)/K(+)-ATPase subunit and reduced Na(+)/K(+)-ATPase activity by ~50 %, consistent with the role of FXYD3 to facilitate reversal of glutathionylation of the β1 subunit of Na(+)/K(+)-ATPase and glutathionylation-induced inhibition of Na(+)/K(+)-ATPase. Treatment of MCF-7 and MDA-MB- 468 cells with doxorubicin or γ-radiation decreased cell viability and induced apoptosis. The treatments upregulated FXYD3 expression in MCF-7 but not in MDA-MB-468 cells and suppression of FXYD3 in MCF-7 but not in MDA-MB-468 cells amplified effects of treatments on Na(+)/K(+)-ATPase activity and treatment-induced cell death and apoptosis. Overexpression of FXYD3 may be a marker of resistance to cancer treatments and a potentially important therapeutic target.

The prognostic factors and multiple biomarkers in young patients with colorectal cancer

The incidence of colorectal cancer (CRC) in young patients (≤50 years of age) appears to be increasing. However, their clinicopathological characteristics and survival are controversial. Likewise, the biomarkers are unclear. We used the West China (2008-2013, China), Surveillance, Epidemiology, and End Results program (1973-2011, United States) and Linköping Cancer (1972-2009, Sweden) databases to analyse clinicopathological characteristics, survival and multiple biomarkers of young CRC patients. A total of 509,934 CRC patients were included from the three databases. The young CRC patients tended to have more distal location tumours, fewer tumour numbers, later stage, more mucinous carcinoma and poorer differentiation. The cancer-specific survival (CSS) of young patients was significantly better. The PRL (HR = 12.341, 95% CI = 1.615-94.276, P = 0.010), RBM3 (HR = 0.093, 95% CI = 0.012-0.712, P = 0.018), Wrap53 (HR = 1.952, 95% CI = 0.452-6.342, P = 0.031), p53 (HR = 5.549, 95% CI = 1.176-26.178, P = 0.045) and DNA status (HR = 17.602, 95% CI = 2.551-121.448, P = 0.001) were associated with CSS of the young patients. In conclusion, this study suggests that young CRC patients present advanced tumours and more malignant pathological features, while they have a better prognosis. The PRL, RBM3, Wrap53, p53 and DNA status are potential prognostic biomarkers for the young CRC patients.

AEG-1 expression is an independent prognostic factor in rectal cancer patients with preoperative radiotherapy: a study in a Swedish clinical trial

Background:

Preoperative radiotherapy (RT) is widely used to downstage rectal tumours, but the rate of recurrence varies significantly. Therefore, new biomarkers are needed for better treatment and prognosis. It has been shown that astrocyte elevated gene-1 (AEG-1) is a key mediator of migration, invasion, and treatment resistance. Our aim was to analyse the AEG-1 expression in relation to RT in rectal cancer patients and to test its radiosensitising properties.

Methods:

The AEG-1 expression was examined by immunohistochemistry in 158 patients from the Swedish clinical trial of RT. Furthermore, we inhibited the AEG-1 expression by siRNA in five colon cancer cell lines and measured the survival after irradiation by colony-forming assay.

Results:

The AEG-1 expression was increased in the primary tumours compared with the normal mucosa independently of the RT (P<0.01). High AEG-1 expression in the primary tumour of the patients treated with RT correlated independently with higher risk of distant recurrence (P=0.009) and worse disease-free survival (P=0.007). Downregulation of AEG-1 revealed a decreased survival after radiation in radioresistant colon cancer cell lines.

Conclusions:

The AEG-1 expression was independently related to distant recurrence and disease-free survival in rectal cancer patients with RT and could therefore be a marker to discriminate patients for distant relapse.

Tafazzin protein expression is associated with tumorigenesis and radiation response in rectal cancer: a study of Swedish clinical trial on preoperative radiotherapy

BACKGROUND

Tafazzin (TAZ), a transmembrane protein contributes in mitochondrial structural and functional modifications through cardiolipin remodeling. TAZ mutations are associated with several diseases, but studies on the role of TAZ protein in carcinogenesis and radiotherapy (RT) response is lacking. Therefore we investigated the TAZ expression in rectal cancer, and its correlation with RT, clinicopathological and biological variables in the patients participating in a clinical trial of preoperative RT.

METHODS

140 rectal cancer patients were included in this study, of which 65 received RT before surgery and the rest underwent surgery alone. TAZ expression was determined by immunohistochemistry in primary cancer, distant, adjacent normal mucosa and lymph node metastasis. In-silico protein-protein interaction analysis was performed to study the predictive functional interaction of TAZ with other oncoproteins.

RESULTS

TAZ showed stronger expression in primary cancer and lymph node metastasis compared to distant or adjacent normal mucosa in both non-RT and RT patients. Strong TAZ expression was significantly higher in stages I-III and non-mucinious cancer of non-RT patients. In RT patients, strong TAZ expression in biopsy was related to distant recurrence, independent of gender, age, stages and grade (p = 0.043, HR, 6.160, 95% CI, 1.063-35.704). In silico protein-protein interaction study demonstrated that TAZ was positively related to oncoproteins, Livin, MAC30 and FXYD-3.

CONCLUSIONS

Strong expression of TAZ protein seems to be related to rectal cancer development and RT response, it can be a predictive biomarker of distant recurrence in patients with preoperative RT.

Livin expression is an independent factor in rectal cancer patients with or without preoperative radiotherapy

BACKGROUND

This study was aimed to investigate the expression significance of Livin in relation to radiotherapy (RT), clinicopathological and biological factors of rectal cancer patients.

METHODS

This study included 144 primary rectal cancer patients who participated in a Swedish clinical trial of preoperative radiotherapy. Tissue microarray samples from the excised primary rectal cancers, normal mucosa and lymph node metastases were immunostained with Livin antibody. The proliferation of colon cancer cell lines SW620 and RKO was assayed after Livin knock-down.

RESULTS

The expression of Livin was significantly increased from adjacent (P = 0.051) or distant (P = 0.028) normal mucosa to primary tumors. 15.4% (2/13) and 39.7% (52/131) patients with Livin-negative and positive tumors died at 180 months after surgery, and the difference tended to be statistically significant (P = 0.091). In multivariate analyses, the difference achieved statistical significance, independent of TNM stage, local and distant recurrence, grade of differentiation, gender, and age (odds ratio = 5.09, 95% CI: 1.01-25.64, P = 0.048). The in vitro study indicated colon cancer cells with Livin knock-down exhibited decreased proliferation compared with controls after RT.

CONCLUSIONS

The expression of Livin was was independently related to survival in rectal cancer patients, suggesting Livin as a useful prognostic factor for rectal cancer patients.

Tissue-based proteomics reveals FXYD3, S100A11 and GSTM3 as novel markers for regional lymph node metastasis in colon cancer

Regional lymph node metastasis negatively affects prognosis in colon cancer patients. The molecular processes leading to regional lymph node metastasis are only partially understood and proteomic markers for metastasis are still scarce. Therefore, a tissue-based proteomic approach was undertaken for identifying proteins associated with regional lymph node metastasis. Two complementary tissue-based proteomic methods have been employed. MALDI imaging was used for identifying small proteins (≤25 kDa) in situ and label-free quantitative proteomics was used for identifying larger proteins. A tissue cohort comprising primary colon tumours without metastasis (UICC II, pN0, n = 21) and with lymph node metastasis (UICC III, pN2, n = 33) was analysed. Subsequent validation of identified proteins was done by immunohistochemical staining on an independent tissue cohort consisting of primary colon tumour specimens (n = 168). MALDI imaging yielded ten discriminating m/z species, and label-free quantitative proteomics 28 proteins. Two MALDI imaging-derived candidate proteins (FXYD3 and S100A11) and one from the label-free quantitative proteomics (GSTM3) were validated on the independent tissue cohort. All three markers correlated significantly with regional lymph node metastasis: FXYD3 (p = 0.0110), S100A11 (p = 0.0071), and GSTM3 (p = 0.0173). FXYD3 and S100A11 were more highly expressed in UICC II patient tumour tissues. GSTM3 was more highly expressed in UICC III patient tumour tissues. By our tissue-based proteomic approach, we could identify a large panel of proteins which are associated with regional lymph node metastasis and which have not been described so far. Here we show that novel markers for regional lymph metastasis can be identified by MALDI imaging or label-free quantitative proteomics and subsequently validated on an independent tissue cohort.

A monoclonal antibody against human FXYD6

Previous research has shown that FXYD6 (FXYD domain-containing ion transport regulator 6) is highly increased in bile duct tumor. However, the biological function of FXYD6 is unclear. We aim to prepare and identify a monoclonal antibody against FXYD6, which will be used in diagnostics and as a tool in understanding the role of FXYD6 in pathogenesis of hepatobiliary cancer. In this study, hybridoma cell fusion technology is used for production of FXYD6 monoclonal antibody. BALB/c mice are immunized with FXYD6 synthetic peptide fragment. Hybridoma clones are screened using indirect enzyme-linked immunosorbent assay (ELISA). FXYD6 monoclonal antibody is produced by ascites revulsion. Protein A affinity chromatography is used for the purification of FXYD6 monoclonal antibody. Titer and specificity of monoclonal antibody are assessed by ELISA. Expression of FXYD6 in pancreatic cancer is detected by immunohistochemistry. As a result, one stable hybridoma cell clone producing FXYD6 monoclonal antibody has been established. 2.86 mg monoclonal antibody against FXYD6 with high specificity is prepared with titer of 1:5400. Immunohistochemistry shows that FXYD6 positive staining occurs in the cell membrane of pancreatic cancer, which results in an advantage in investigating the tissue distribution and biological function of FXYD6.

Expression of NF-κB p65 phosphorylated at serine-536 in rectal cancer with or without preoperative radiotherapy

BACKGROUND

In the present study, we investigated NF-κB p65 phosphorylated at Serine-536 (phosphor-Ser536-p65) in rectal cancer and its relationship to preoperative radiotherapy (RT), clinicopathological variables and biological factors.

PATIENTS AND METHODS

Expression of phosphor-Ser536-p65 was examined by using immunohistochemistry in 141 primary rectal cancers, 149 normal mucosa specimens and 48 metastases in the lymph nodes, from rectal cancer patients who participated in a Swedish clinical trial of preoperative RT.

RESULTS

The expression of phosphor-Ser536-p65 in the cytoplasm increased from normal mucosa to primary tumour (p<0.0001, for both the group that did and the group that did not received RT). The expression did not further increase from primary tumour to metastasis in either group (p>0.05). Expression of phosphor-Ser536-p65 was positively related to, or tended to be related to, the expression of tumour endothelium marker 1 (TEM1, p=0.02), FXYD-3 (p=0.001), phosphatase of regenerating liver (PRL, p=0.02), p73 (p=0.048) and meningioma associated protein (MAC30, p=0.05) in the group that received RT but there were no such relationships in the group that did not received RT (p>0.05). The expression of phosphor-Ser536-p65 was not related to clinicopathological factors including survival (p>0.05).

CONCLUSIONS

The increased expression of phosphor-Ser536-p65 may be involved in rectal cancer development. After RT, phosphor-Ser536-p65 seems to be positively related to the biological factors, which associated with more malignant features of tumours. However, phosphor-Ser536-p65 was not directly related to the response of RT based on recurrence and survival.