Breast cancer is the most common cancer in women, and radiotherapy is an important method of its treatment. The outcome of radiotherapy greatly depends on radiosensitivity of cancer cells. The key pathways of microRNAs (miRNAs) involved in breast cancer radiotherapy response include DNA damage repair, apoptosis, cell cycle arrest, autophagy and related signaling pathways. This article reviews the role of miRNAs in regulating the response of breast cancer to radiotherapy and related signaling pathways. To explore the role of miRNAs in regulating the treatment response of breast cancer to radiotherapy and related signaling pathways, it can provide reference for miRNAs to be used as an indicator to evaluate the diagnosis, prognosis and radiotherapy efficacy of breast cancer.

Objective To evaluate the effect of indwelling nasointestinal tube for enteral nutrition (EN) support on patients with severe craniocerebral trauma undergoing mechanical ventilation (MV). Methods A total of 100 severe craniocerebral trauma patients undergoing MV admitted to intensive care unit (ICU) of the 117th Hospital of People's Liberation Army from February 2015 to February 2017 were enrolled, and they were divided into nasogastric tube group in which the EN was fed by nasogastric tube and nasal jejunal feeding tube group (nasointestinal tube group) by random digits table, with 50 patients in each group. Blood urea nitrogen (BUN), hemoglobin (Hb), serum albumin (Alb), acute physiology and chronic health evaluation Ⅱ(APACHEⅡ) score, Glasgow coma scale (GCS) score before and 10 days after treatment, duration of MV, hospitalization time, and the incidences of ventilator-associated pneumonia (VAP) and reflux wrong aspiration of the two groups were observed and compared. Results There was no statistically significant difference in BUN, Hb, Alb, APACHEⅡscore or GCS score before treatment between the two groups. Ten days after treatment, BUN and APACHEⅡ score in the nasointestinal tube group were significantly lower than those in the nasogastric tube group [BUN (mmol/L): 6.3±1.6 vs. 8.0±2.2, APACHEⅡscore: 17.9±3.2 vs. 20.8±6.3, both P < 0.05], Hb, Alb, GCS score were significantly higher than those in nasogastric tube group [Hb (g/L): 125.9±19.7 vs. 113.5±19.6, Alb (g/L): 35.9±6.2 vs. 31.9±6.2, GCS score: 9.7±1.9 vs. 8.2±5.7, all P < 0.05], duration of MV and hospitalization time were significantly less than those in the nasogastric tube group [duration of MV (days):14.7±3.4 vs. 17.5±2.9, hospitalization time (days): 15.4±5.6 vs. 19.2±7.3, both P < 0.05], and the complication rate in nasointestinal tube group was obviously lower than that in nasogastric tube group [10% (5/50) vs. 36% (18/50), P < 0.05]. Conclusion For patients with severe craniocerebral trauma treated with MV, the EN treatment by means of indwelling nasointestinal tube is helpful for the recovery of consciousness, improvement of nutritional indexes, reduction of incidences of complications such as reflux aspiration, etc. and shortening the course of disease, thus the method can obviously improve the patients quality of life.

Objective:To investigate the methylation status of SDC2, PPP2R5C and ADHFE1 genes in stool and their values in the screening of colorectal cancer and precancerous lesions.Methods:From August 2020 to March 2021, 64 patients with colorectal cancer, 72 patients with adenoma, 33 patients with hyperplastic polyps and 59 healthy people were recruited from Qingdao Central Hospital Affiliated to Qingdao University, and the morning stool samples were collected from the research subjects. The genomic DNA was extracted and modified with sulfite. The methylation status of SDC2, PPP2R5C and ADHFE1 genes were detected by methylation specific polymerase chain reaction (MSP), and the fecal occult blood test (FOBT) was performed. Taking the pathological results as the gold standard, receiver operating characteristic (ROC) curve and area under the curve (AUC) were used to compare the effect of combined detection of methylation of three genes and FOBT in predicting colorectal cancer and precancerous lesions. R-Studio software was used to construct a nomogram for the prediction of colorectal cancer with combined detection of gene methylation in stool and other clinical features, and the calibration and validation were performed.Results:The positive rates of combined detection of methylation of SDC2, PPP2R5C and ADHFE1 genes in stool were higher than those of FOBT in colorectal cancer+adenoma [74.3% (101/136) vs. 47.1% (64/136), χ2 = 23.20, P = 0.001], colorectal cancer [90.6% (58/64) vs. 70.3% (45/64), χ2 = 8.91, P = 0.003] and adenoma [59.7% (43/72) vs. 26.4% (19/72), χ2 = 14.43, P = 0.002]. There was no significant difference in the positive rates in hyperplastic polyps [21.2% (7/33) vs. 6.1% (2/33), χ2 = 0.12, P = 0.125] and healthy controls [10.2% (6/59) vs. 8.5% (5/59), χ2 = 4.01, P = 1.000]. The combined detection of gene methylation was better than FOBT in the prediction of colorectal cancer + adenoma [AUC: 0.85 (95% CI 0.80-0.91) vs. 0.71 (95% CI 0.64-0.78), P < 0.05], especially in the prediction of adenoma [AUC: 0.82 (95% CI 0.74-0.89) vs 0.64 (95% CI 0.57-0.69), P < 0.001]. The sensitivity and specificity of ADHFE1 gene methylation status in predicting colorectal cancer were high (90.6% and 96.6%). In colorectal cancer patients over 50 years old, the positive rate of combined detection of gene methylation was higher than that of FOBT [90.2% (55/61) vs. 68.9% (42/61), P < 0.05]. The nomogram calibration curve for predicting colorectal cancer constructed based on the combined detection of gene methylation and each clinical feature showed a high degree of concordance between the predicted and observed diagnostic performance of colorectal cancer. Conclusions:The methylation levels of SDC2, PPP2R5C AND ADHFE1 genes in stool are increased in patients with colorectal cancer or adenoma. The combined detection of gene methylation is expected to be a non-invasive method for the screening of colorectal cancer and precancerous lesions.