AIM:To investigate the association between nuclearβ-catenin overexpression in rectal adenocarcinoma and radioresistance.METHODS:A retrospective analysis was conducted.The analysis involved 136 patients with locally advanced rectal adenocarcinoma who underwent shortcourse preoperative radiotherapy and radical resection.The expression ofβ-catenin in both pretreatment biopsy specimens and resected primary tumor tissues was examined by immunohistochemistry.The correlation ofβ-catenin expression with radioresistance was evaluated using the tumor regression grading(TRG)system.The relationship betweenβ-catenin expression and clinicopathological characteristics was also analyzed.Univariate and logistic multivariate regression analyses were adopted to determine the independent factors of radioresistance.RESULTS:Nuclearβ-catenin overexpression was more evident in radioresistant rectal adenocarcinoma than in radiosensitive rectal adenocarcinoma(57.6%vs 16.7%,P<0.001).Nuclearβ-catenin was overexpressed in favor of poor TRG(≤2),whereas membraneβ-catenin was expressed in favor of good TRG(≥3).Nuclearβ-catenin expression in tumor cell differentiation(P=0.018),lymph node metastasis(P=0.022),and TRG(P<0.001)showed significant differences.Univariate analyses demonstrated that radioresistance is associated with nuclearβ-catenin overexpression(P<0.001).In addition,logistic multivariate regression analysis indicated that only three factors,namely,tumor size(P<0.001),tumor cell differentiation(P<0.001),and nuclearβ-catenin overexpression(P<0.001),are associated with radioresistance.By using radioresistance as a prediction target,nuclearβ-catenin-based prediction alone achieved 83%accuracy,65%sensitivity,and88%specificity.CONCLUSION:Nuclearβ-catenin overexpression may be a valuable candidate to predict the response of rectal adenocarcinoma to preoperative radiotherapy. AIM: To investigate the association between nuclear β-catenin overexpression in rectal adenocarcinoma and radioresistance. METHODS: A retrospective analysis performed conducted. The analysis involved 136 patients with locally advanced rectal adenocarcinoma who underwent shortourse preoperative radiotherapy and radical resection. The expression of β-catenin in both pretreatment biopsy specimens and resected primary tumor tissues was examined by immunohistochemistry. The correlation of β-catenin expression with radioresistance was evaluated using the tumor regression grading (TRG) system. The relationship between β-catenin expression and clinicopathological characteristics was also analyzed. Univariate and logistic multivariate regression analyzes were adopted to determine the independent factors of radioresistance .RESULTS: Nuclear β-catenin overexpression was more evident in radioresistant rectal adenocarcinoma than in radiosensitive rectal adenocarcinoma (57.6% vs 16.7%, P <0.001) .Nuclear β-catenin was ov catechin was expressed in favor of good TRG (≥3) .Nuclearβ-catenin expression in tumor cell differentiation (P = 0.018), lymph node metastasis (P = 0.022), (P <0.001) showed significant differences. Univariate analysis of the radioresistance is associated with nuclear β-catenin overexpression (P <0.001) .In addition, logistic multivariate regression analysis indicated that only three factors, namely, tumor size ), tumor cell differentiation (P <0.001), and nuclear β-catenin overexpression (P <0.001), are associated with radioresistance.By using radioresistance as a prediction target, nuclear β-catenin-based prediction alone achieved 83% accuracy, 65% sensitivity , and88% specificity.CONCLUSION: Nuclear β-catenin overexpression may be a valuable candidate to predict the response of rectal adenocarcinoma to preoperative radiotherapy.