[Construction of a model based on multipoint full-layer puncture biopsy for predicting pathological complete response after neoadjuvant therapy for locally advanced rectal cancer]

Objective: To investigate the value of transanal multipoint full-layer puncture biopsy (TMFP) in predicting pathological complete response (pCR) after neoadjuvant radiotherapy and chemotherapy (nCRT) in patients with locally advanced rectal cancer (LARC) and to establish a predictive model for providing clinical guidance regarding the treatment of LARC. Methods: In this multicenter, prospective, cohort study, we collected data on 110 LARC patients from four hospitals between April 2020 and March 2023: Beijing Chaoyang Hospital of Capital Medical University (50 patients), Beijing Friendship Hospital of Capital Medical University (41 patients), Qilu Hospital of Shandong University (16 patients), and Zhongnan Hospital of Wuhan University (three patients). The patients had all received TMFP after completing standard nCRT. The variables studied included (1) clinicopathological characteristics; (2) clinical complete remission (cCR) and efficacy of TMFP in determining pCR after NCRT in LARC patients; and (3) hospital attended, sex, age, clinical T- and N-stages, distance between the lower margin of the tumor and the anal verge, baseline and post-radiotherapy serum carcinoembryonic antigen (CEA) and carbohydrate antigen (CA)19-9 concentrations, chemotherapy regimen, use of immunosuppressants with or without radiotherapy, radiation therapy dosage, interval between surgery and radiotherapy, surgical procedure, clinical T/N stage after radiotherapy, cCR, pathological results of TMFP, puncture method (endoscopic or percutaneous), and number and timing of punctures. Single-factor and multifactorial logistic regression analysis were used to determine the factors affecting pCR after NCRT in LARC patients. A prediction model was constructed based on the results of multivariat analysis and the performance of this model evaluated by analyzing subject work characteristics (ROC), calibration, and clinical decision-making (DCA) curves. pCR was defined as complete absence of tumor cells on microscopic examination of the surgical specimens of rectal cancer (including lymph node dissection) after NCRT, that is, ypT0+N0. cCR was defined according to the Chinese Neoadjuvant Rectal Cancer Waiting Watch Database Study Collaborative Group criteria after treatment, which specify an absence of ulceration and nodules on endoscopy; negative rectal palpation; no tumor signals on rectal MRI T2 and DWI sequences; normal serum CEA concentrations, and no evidence of recurrence on pelvic computed tomography/magnetic resonance imaging. Results: Of the 110 patients, 45 (40.9%) achieved pCR after nCRT, which was combined with immune checkpoint inhibitors in 34 (30.9%). cCR was diagnosed before puncture in 38 (34.5%) patients, 43 (39.1%) of the punctures being endoscopic. There were no complications of puncture such as enterocutaneous fistulae, vaginal injury, prostatic injury, or presacral bleeding . Only one (2.3%) patient had a small amount of blood in the stools, which was relieved by anal pressure. cCR had a sensitivity of 57.8% (26/45) for determining pCR, specificity of 81.5% (53/65), accuracy of 71.8% (79/110), positive predictive value 68.4% (26/38), and negative predictive value of 73.6% (53/72). In contrast, the sensitivity of TMFP pathology in determining pCR was 100% (45/45), specificity 66.2% (43/65), accuracy 80.0% (88/110), positive predictive value 67.2% (45/67), and negative predictive value 100.0% (43/43). In this study, the sensitivity of TMFP for pCR (100.0% vs. 57.8%, χ2=24.09, P<0.001) was significantly higher than that for cCR. However, the accuracy of pCR did not differ significantly (80.0% vs. 71.8%, χ2=2.01, P=0.156). Univariate and multivariate logistic regression analyses showed that a ≥4 cm distance between the lower edge of the tumor and the anal verge (OR=7.84, 95%CI: 1.48-41.45, P=0.015), non-cCR (OR=4.81, 95%CI: 1.39-16.69, P=0.013), and pathological diagnosis by TMFP (OR=114.29, the 95%CI: 11.07-1180.28, P<0.001) were risk factors for pCR after NCRT in LARC patients. Additionally, endoscopic puncture (OR=0.02, 95%CI: 0.05-0.77, P=0.020) was a protective factor for pCR after NCRT in LARC patients. The area under the ROC curve of the established prediction model was 0.934 (95%CI: 0.892-0.977), suggesting that the model has good discrimination. The calibration curve was relatively close to the ideal 45° reference line, indicating that the predicted values of the model were in good agreement with the actual values. A decision-making curve showed that the model had a good net clinical benefit. Conclusion: Our predictive model, which incorporates TMFP, has considerable accuracy in predicting pCR after nCRT in patients with locally advanced rectal cancer. This may provide a basis for more precisely selecting individualized therapy.

[The value of transanal multipoint full-layer puncture biopsy in determining the response degree of rectal cancer following neoadjuvant therapy: a prospective multicenter study]

Objective: To verify the feasibility and accuracy of the transanal multipoint full-layer puncture biopsy (TMFP) technique in determining the residual status of cancer foci after neoadjuvant therapy (nCRT) in rectal cancer. Methods: Between April 2020 and November 2022, a total of 78 patients from the Beijing Chaoyang Hospital of Capital Medical University, the Beijing Friendship Hospital of Capital Medical University, the Qilu Hospital of Shandong University, the Zhongnan Hospital of Wuhan University with advanced rectal cancer received TMFP after nCRT participated in this prospective multicenter trial. There were 53 males and 25 females, aged (M(IQR)) 61 (13) years (range: 35 to 77 years). The tumor distance from the anal verge was 5 (3) cm (range: 2 to 10 cm). The waiting time between nCRT and TMFP was 73 (26) days (range: 33 to 330 days). 13-point transanal puncture was performed with a 16 G tissue biopsy needle with the residual lesion as the center. The specimens were submitted for independent examination and the complications of the puncture were recorded. The consistency of TMFP and radical operation specimen was compared. The consistency of TMPF with clinical remission rates for the diagnosis of complete pathological remission was compared by sensitivity, specificity, negative predictive value, positive predictive value and accuracy. Statistical analysis between groups was performed using the χ2 analysis, and a paired χ2 test was used to compare diagnostic validity. Results: Before TMFP, clinical complete response (cCR) was evaluated in 27 cases. Thirty-six cases received in vivo puncture, the number of punctures in each patient was 13 (8) (range: 4 to 20), 24 cases of tumor residue were found in the puncture specimens. The sensitivity to judgment (100% vs. 60%, χ2=17.500, P<0.01) and accuracy (88.5% vs. 74.4%, χ2=5.125, P=0.024) of TMFP for the pathologic complete response (pCR) were significantly higher than those of cCR. Implement TMFP based on cCR judgment, the accuracy increased from 74.4% to 92.6% (χ2=4.026, P=0.045). The accuracy of the in vivo puncture was 94.4%, which was 83.3% of the in vitro puncture (χ2=1.382, P=0.240). Overall, the accuracy of TMFP improved gradually with an increasing number of cases (χ2=7.112, P=0.029). Conclusion: TMFP is safe and feasible, which improves the sensitivity and accuracy of rectal cancer pCR determination after nCRT, provides a pathological basis for cCR determination, and contributes to the safe development of the watch and wait policy.

[Effect of intestinal obstruction stent combined with neoadjuvant chemotherapy on the pathological characteristics of surgical specimens in patients with complete obstructive colorectal cancer]

Objective: To compare the effects of three treatment options: emergency surgery, stent-surgery, and stent-neoadjuvant chemotherapy-surgery, on the pathological characteris- tics of surgically-resected specimens from patients with completely obstructive colorectal cancer. Methods: This was a retrospective cohort study analyzing clinicopathological data of patients with complete obstructive colorectal cancer who were admitted to the General Surgery Department of Beijing Chaoyang Hospital, Capital Medical University, between May 2012 and August 2020. The inclusion criteria were diagnosed with complete colorectal obstruction, pathologically confirmed as adenocarcinoma, resectable on imaging assessment, and without distant metastasis, combined with the patients' clinical manifestations and imaging examination findings. Patients with multiple colorectal cancers, refusal to undergo surgery, and concurrent peritonitis or intestinal perforation before stenting of the intestinal obstruction were excluded. Eighty-nine patients with completely obstructive colorectal cancer were enrolled in the study and were divided into emergency surgery group (n=30), stent-surgery group (n=34), and stent-neoadjuvant chemotherapy- surgery group (n=25) according to the treatment strategy. Differences in the pathological features (namely perineural infiltration, lymphovascular infiltration, tumor deposits, specimen intravascular necrosis, inflammatory infiltration, abscesses, mucus lake formation, foreign body giant cells, calcification, and tumor cell ratio) and biomolecular markers (namely cluster of differentiation (CD)34, Ki67, Bcl-2, matrix metalloproteinase-9, and hypoxia-inducible factor alpha) were recorded. Pathological evaluation was based on the presence or absence of qualitative evaluation of pathological features, such as peripheral nerve infiltration, vascular infiltration, and cancer nodules within the specimens. The evaluation criteria for the pathological features of the specimens were as follows: Semi-quantitative graded evaluation based on the proportion of tissue necrosis, inflammatory infiltrates, abscesses, mucus lake formation, foreign body giant cells, calcification, and tumor cells in the field of view within the specimen were classified as: grade 0: not seen within the specimen; grade 1: 0-25%; grade 2: 25%-50%; grade 3: 50%-75%; and grade 4: 75%-100%. The intensity of cellular immunity was classified as none (0 points), weak (1 point), moderate (2 points), and strong (3 points). The two evaluation scores were then multiplied to obtain a total score of 0-12. The immunohistochemical results were also evaluated comprehensively, and the results were defined as: negative (grade 0): 0 points; weakly positive (grade 1): 1-3 points; moderately positive (grade 2): 4-6 points; strongly positive (grade 3): 7-9 points; and very strong positive (grade 4): 10-12 points. Normally-distributed values were expressed as mean±standard deviation, and one-way analysis of variance was used to analyze the differences between the groups. Non-normally-distributed values were expressed as median (interquartile range: Q1, Q3). A nonparametric test (Kruskal-Wallis H test) was used for comparisons between groups. Results: The differences were not statistically significant when comparing the baseline data for age, gender, tumor site, American Society of Anesthesiologists score, tumor T-stage, N-stage, and degree of differentiation among the three groups (all P>0.05). The differences were not statistically significant when comparing the pathological characteristics of the resected tumor specimens, such as foreign body giant cells, inflammatory infiltration, and mucus lake formation among the three groups (all P>0.05). The rates of vascular infiltration were 56.6% (17/30), 41.2% (15/34), and 20.0% (5/25) in the emergency surgery, stent-surgery, and stent- neoadjuvant chemotherapy-surgery groups, respectively, with statistically significant differences between the groups (χ²=7.142, P=0.028). Additionally, the rate of vascular infiltration was significantly lower in the stent-neoadjuvant chemotherapy-surgery group than that in the emergency surgery group (P=0.038). Peripheral nerve infiltration rates were 55.3% (16/30), 41.2% (14/34), and 16.0% (4/25), in the emergency surgery, stent-surgery, and stent-neoadjuvant chemotherapy-surgery groups, respectively, with statistically significant differences (χ²=7.735, P=0.021). The infiltration peripheral nerve rates in the stent-neoadjuvant chemotherapy-surgery group were significantly lower than those in the emergency surgery group (P=0.032). The necrosis grade was 2 (1, 2), 2 (1, 3), and 2 (2, 3) in the emergency surgery, stent- surgery, and stent-neoadjuvant chemotherapy-surgery groups, respectively, with statistically significant differences (H=10.090, P=0.006). Post hoc comparison revealed that the necrosis grade was higher in the stent-surgery and stent-neoadjuvant chemotherapy-surgery groups compared with the emergency surgery group (both P<0.05). The abscess grade was 2 (1, 2), 3 (1, 3), and 2 (2, 3) in the emergency surgery, stent-surgery, and stent-neoadjuvant chemotherapy-surgery groups, respectively, with statistically significant differences (H=6.584, P=0.037). Post hoc comparison revealed that the abscess grade in the emergency surgery group was significantly lower than that in the stent-surgery group (P=0.037). The fibrosis grade was 2 (1, 3), 3 (2, 3), and 3 (2, 3), in the emergency surgery, stent-surgery, and stent-neoadjuvant chemotherapy-surgery groups, respectively, with statistically significant differences (H=11.078, P=0.004). Post hoc analysis revealed that the fibrosis degree was higher in both the stent-surgery group and the stent- neoadjuvant chemotherapy-surgery group compared with the emergency surgery group (both, P<0.05). The tumor cell ratio grades were 4 (3, 4), 4 (3, 4), and 3 (2, 4), in the emergency surgery, stent-surgery, and stent-neoadjuvant chemotherapy-surgery groups, respectively, with statistically significant differences (H=8.594, P=0.014). Post hoc analysis showed that the tumor cell ratio in the stent-neoadjuvant chemotherapy-surgery group was significantly lower than that in the emergency surgery group (P=0.012). The CD34 grades were 2 (2, 3), 3 (2, 4), and 3 (2, 3) in the emergency surgery, stent-surgery, and stent-neoadjuvant chemotherapy-surgery groups, respectively, and the difference was statistically significant (H=9.786, P=0.007). Post hoc analysis showed that the CD34 grades in the emergency surgery, stent-surgery, and stent-neoadjuvant chemotherapy-surgery groups were 2 (2, 3), 3 (2, 4), and 3 (2,3), respectively. Post hoc analysis revealed that the CD34 concentration was higher in the stent-surgery group than that in the emergency surgery group (P=0.005). Conclusion: Stenting may increase the risk of distant metastases in obstructive colorectal cancer. The stent-neoadjuvant chemotherapy-surgery treatment model promotes tumor cell necrosis and fibrosis and reduces the proportion of tumor cells, vascular infiltration, and peripheral nerve infiltration, which may help decrease local tumor infiltration and distant metastasis in completely obstructive colorectal cancer after stent placement.

Horizontal Rafting Plate for Treatment of the Tibial Plateau Fracture

Objective

This study aimed to investigate the value of a horizontal rafting plate in treating tibial plateau fractures.

Methods

The data of 24 patients in whom a horizontal rafting plate was used to treat a tibial plateau fracture between October 2014 and January 2018 were retrospectively analyzed, including 16 males and 8 females, aged 21–63 years old, with an average of 40 ± 14.68 years. The fractures included 13 in the left knee and 11 in the right knee. The places where the horizontal rafting plate were used included the anterior margin of tibia, anterolateral tibia, and posterolateral tibia. All cases were followed up for 12–24 months, with an average follow‐up of 17.5 ± 5.0 months. At the last follow‐up, the Rasmussen radiological criteria were used to evaluate the effect of fracture reduction and fixation. The knee joint function was evaluated using the Rasmussen functional score. Computed tomography (CT) scanning and three‐dimensional reconstruction were performed preoperatively and postoperatively, with the quality of reduction of the fractured articular surface clarified by the final follow‐up. The flexion and extension abilities of the knee joint were also measured in the postoperative follow‐up.

Results

Preoperative CT scanning showed that the gap of the tibial plateau was 8.00 ± 1.40 (5–24) mm. The heights of the fracture of the articular surface at all three sites during the final follow‐ups were significantly different from the height before the surgery (P < 0.05). The vertical distance between the articular line and the highest point of the articular surface after reduction was 0.17 ± 0.05 mm. Anatomic reductions were obtained in 24 patients. The Rasmussen functional score after surgeries was 27.25 ± 0.94 points. Bony union was achieved in all the patients. According to the Rasmussen radiological criteria, the scores during the last follow‐up were as follows: the total score was 13–18 points, with an average of 16.00 ± 1.72 points; the scores were excellent in 17 cases and good in seven cases. Therefore, 100% of results were excellent or good. No infection or fracture nonunion was found.

Conclusion

Using a horizontal plate can be an effective method for treating special types of fractures of the tibial plateau, including the anterior margin and anterolateral and posterolateral tibial plateau, with satisfactory treatment efficacy.

[Long-term effect of anal fistula plug treatment on postoperative anal function in patients with trans-sphincteric perianal fistula and risk factors associated with anal function]

Objective: To evaluate the long-term effects of anal fistula plug treatment on postoperative anal function in patients with trans-sphincteric perianal fistula, and identify risk factors associated with anal function. Methods: A case-control study was conducted. Clinical and follow-up data of 123 patients with trans-sphincteric perianal fistula receiving anal fistula plug treatment in Beijing Chaoyang Hospital from August 2008 to September 2012 were retrospectively analyzed. The follow-up deadline was April 30, 2020. The Wexner score for incontinence was used to evaluate pre-and postoperative anal function (range from 0 to 20, with higher score representing worse function). The potential risk factors affecting postoperative anal function, including gender, age, fasting blood glucose, diabetes, smoking, alcoholism, location of external opening of anal fistula, surgeon expertise and operation time, were statistically analyzed. Results: Among the 123 patients, 114 were male and 9 were female, the median age was 39 (15-69) years, body mass index (BMI) was (26.2±3.9) kg/m(2), and the median distance between the external opening of anal fistula and the anal verge was 2.6 (1.0-5.0) cm. The median operation time was 30.4 (15.0-60.0) minutes. The median follow-up time was 120 (93-141) months. Sixty-nine patients (56.5%) were healed. The assessment of anal function by Wexner incontinence score showed that 33 (26.8%) patients had anal functional decline after surgery, and the postoperative median Wexner score was 1.34 (0-8), which was significantly higher than preoperative score of 0.17 (0-4) (Z=-5.057, P<0.001). Compared with preoperative levers, postoperative subscores of flatus incontinence, liquid incontinence, solid incontinence and alteration in lifestyle were increased significantly (all P<0.05). Subgroup analysis showed that both in the healed and unhealed groups, the postoperative Wexner scores were higher than those before surgery [healed group: 1.22 (0-8) vs. 0.17 (0-1), Z=-3.796, P<0.001; unhealed group: 1.5 (0-8) vs.0.17 (0-3), Z=-3.422, P=0.001]. Univariate analysis revealed that 33 patients with postoperative anal functional decline had higher BMI, higher fasting blood glucose, higher proportion of alcoholism, longer distance between external opening of anal fistula and the anal verge, and longer operation time (all P<0.05). Multivariate logistic regression analysis testified that higher BMI (OR=1.485, 95% CI: 1.220-1.807, P<0.001) and longer distance between external opening and anal verge (OR=2.207, 95% CI: 1.276-3.220, P=0.003) were independent risk factors for postoperative anal functional decline. Conclusions: The treatment for trans-sphincteric anal fistula with anal fistula plug leads to long-term postoperative anal function decline. For patients with obesity and longer distance between external opening of anal fistula and the anal verge, this procedure should be performed with particular caution, and the anal sphincter should be preserved as much as possible during the operation.

[Surgical treatment of the complex bicondylar tibial plateau fracture using a midline longitudinal incision]

Objective: To explore the outcomes after treatment of the complex bicondylar tibial plateau fracture through a midline longitudinal approach. Methods: A review of fifteen patients with an average age of (51.3±12.3) years old (range17-65yers;7 males, 8 females) surgically treated from October 2013 to Febuary 2018 were included. Sahatker Ⅴ in 10, Sahatker Ⅵ in 5; fractures of medial and lateral columns in 9, fractures of three columns in 6. All the patients were adopt a midline longitudinal approach combined with the posterior approach and bone grafting were conducted. Results: All cases were followed-up for (14.4±3.8) month, with an average of 12-24 month. All patients gained bone union during 12-16 weeks after operation, with an average of (15.2±1.3) weeks. There were significant differeces in both tibial plateau angle and posterior slope angle on radiography between preoperation and postoperation (P<0.05), there were no significant differeces in either tibial plateau angle or posterior slope angle on radiography between immediate postoperation and 12 months postoperation (P>0.05). At final follow-up,both the Lachman test and the Pivot-shift test were negative. All patients had complete knee extension, knee flexion angle 100°-135°, with an average of 117.7°±11.3°. The HSS (the Hospital for Special Surgery) score were 66-98, with an average of 85.1±9.3, six cases were excellent and seven cases were good, two cases was fair, the excellent and good rate was 86.7%. The Rasmussen radiological evaluationre were 9-18, with an average of 15.1±2.5, three cases were excellent and eleven cases were good, one cases was fair, the excellent and good rate was 93.3%. 1 patient had fat liquefactionof in antero incision, and got good outcomes after debridement dressing. Conclusion: The treatment of the complex bicondylar tibial plateau fracture through a midline longitudinal approach combined with the posterior approach can result in good exposure and satisfying knee function in short-term.

[Long-term efficacy of bioprosthetic anal fistula plug in the treatment of transsphincteric anal fistula]

Objective: To evaluate the long-term healing rate of transsphincteric anal fistula treated with anal fistula plug procedure and the risk factors affecting the healing of anal fistula. Methods: A retrospective case-control study was conducted to analyze the clinical data of 207 patients with transsphincteric anal fistulas who received anal fistula plug procedure at the Department of General Surgery, Beijing Chaoyang Hospital of Capital Medical University from August 2008 to September 2012. Inclusion criteria: (1) consistent with the diagnosis of transsphincteric anal fistula: the anal fistula passed through the internal and external sphincter; (2) complete data; (3) initial treatment with anal fistula plug procedure. Exclusion criteria: (1) acute rectal or perianal infection or poorly controlled focal infection; (2) recent incision and drainage of perianal abscess or spontaneous rupture of abscess; (3) patients with malignant tumor; (4) patients with Crohn's disease or ulcerative colitis; (5) patients with heart, liver, brain, lung or renal insufficiency; (6) cachexia due to various chronic wasting diseases; (7) patients could not tolerate surgery. Patients were followed up for anal fistula healing. The cumulative healing rate of patients with transsphincteric anal fistula was plotted using the Kaplan-Meier method, and the factors affecting anal fistula healing were explored by univariate and multivariate logistic regression analysis. Results: There were 186 males and 21 females with age of 15 to 69 (mean 38) years. The duration of anal fistula was 3-60 (mean 15) months. Three patients had a history of previous episodes of perianal abscess and underwent incision and drainage of perianal abscess (all more than 3 months). During follow-up ending on October 31, 2018, 72 patients (34.8%) were lost to follow-up. Among 135 patients who were successfully followed up, the average follow-up period was 96 (75-124) months. Seventy-five patients had anal fistula healing, with healing rate of 55.6%. Kaplan-Meier survival curve showed that the healing time of anal fistula was prolonged and finally stabilized at 55.6%. In the patients who failed initial treatment with anal fistula plug packing, there were 6 cases whose anal fistula healed spontaneously without other treatment. Among them, 3 cases healed spontaneously 2 years and 3 cases 3 years after operation without recurrence. From 2008 to 2012, the annual healing rates of anal fistula plug treatment were 3/6, 61.5% (24/39), 42.1% (24/57), 12/15 and 12/18, respectively. Multivariate logistic regression analysis showed that the duration of anal fistula≥6 months (OR=3.187, 95% CI: 1.361-7.466, P=0.008) was an independent risk factor for anal fistula healing after treatment with anal fistula plug. Conclusion: The long-term efficacy of anal fistula plug procedure in the treatment of transsphincteric anal fistula is positive, and this procedure should be implemented as soon as possible.

Circular RNA circVAPA is up-regulated and exerts oncogenic properties by sponging miR-101 in colorectal cancer

Circular RNAs (circRNAs) are a novel class of non-coding RNAs with distinct properties and diverse physiological and pathological functions. However, the functions of circRNAs in colorectal cancer (CRC) remain elusive. This study aimed to investigate the functional roles of circVAPA in CRC. High-throughput RNA sequencing was performed in 4 paired CRC tissues, and circVAPA (hsa_circ_0006990), was identified as a potential functional circRNA. Using quantitative real-time polymerase chain reaction (qRT-PCR), circVAPA was found to be up-regulated in CRC patients' tissues and plasma. Furthermore, circVAPA level was associated with unfavorable clinicopathologic features in CRC. The area under curve (AUC) of ROC was 0.724, suggesting that plasma level of circVAPA could serve as a promising biomarker for CRC detection. Sanger sequencing confirmed the back-splice junction sequences of circVAPA. Actinomycin D and RNase R treatments suggested that circVAPA was highly stable compared with its linear counterpart, and qRT-PCR for the circVAPA level in nuclear and cytoplasmic fractions indicated that circVAPA was predominantly localized in the cytoplasm. Gain-of-function and loss-of-function studies in CRC cell lines indicated that circVAPA could promote CRC cell proliferation, migration, invasion, and inhibit apoptosis. miRanda software (v3.3a) was used to predict target miRNAs of circVAPA. Moreover, target miRNAs associated with the KEGG pathway of COLORECTAL CANCER (Entry: map05210; https://www.kegg.jp/) were screened using DIANA-miRPath v.3 platform (Reverse Search module; TarBase v7.0 method). The analyses by miRanda and miRPath suggested that circVAPA could potentially bind to hsa-miR-101-3p (miR-101) associated with the COLORECTAL CANCER pathway. Luciferase reporter assay confirmed a direct interaction between circVAPA and miR-101. Furthermore, circVAPA had no effect on the expression level of miR-101, and miR-101 over-expression had the similar tumor-suppressing effects as circVAPA silencing. The tumor-promoting effect of circVAPA over-expression could be reversed by the up-regulation of miR-101. These data demonstrated that circVAPA promoted CRC progression by sponging miR-101. In conclusion, we have verified that circVAPA is up-regulated in CRC patients' tissues and plasma, and exerts oncogenic properties by sponging miR-101 in CRC. CircVAPA could serve as a promising biomarker and a therapeutic target for CRC.

Structural Features of Alkaline Dioxane Lignin and Residual Lignin from Eucalyptus grandis × E. urophylla

In the present study, lignin from eucalyptus was extracted with 80% alkaline dioxane (0.05 M NaOH) from ball-milled wood and subsequently fractionated by gradient acid precipitation from the filtrate. Meanwhile, the residual lignin was prepared by a double enzymatic hydrolysis process. The yield of the lignin extracted by alkaline dioxane (L_A-2) was 29.5%. The carbohydrate contents and molecular weights of the gradient acid precipitated lignin fractions gradually decreased from 4.90 to 1.36% and from 7770 to 5510 g/mol, respectively, with the decline of the pH value from 6 to 2. Results from two-dimensional heteronuclear single quantum coherence nuclear magnetic resonance (NMR) and ³¹P NMR spectroscopy showed an evident reduction of β- O-4 ' linkages with the pH value decrease, while the contents of aliphatic -OH, phenolic -OH, and carboxylic groups displayed an increasing trend. Moreover, the residual lignin exhibited the highest molecular weight (11690 g/mol), the most abundant β- O-4 ' linkages (71.1%), and the highest S/G ratio (4.68).

RNA sequencing reveals the expression profiles of circRNA and indicates that circDDX17 acts as a tumor suppressor in colorectal cancer

Background

Circular RNA (circRNA) is a novel class of noncoding RNAs with functions in various pathophysiological activities. However, the expression profiles and functions of circRNAs in colorectal cancer (CRC) remain largely unknown.

Methods

High-throughput RNA sequencing (RNA-seq) was performed to assess circRNA expression profiles in 4 paired CRC tissues, and significantly dysregulated circRNAs were validated by quantitative real-time polymerase chain reaction (qRT-PCR). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to predict the potential functions of dysregulated circRNAs. Target miRNAs of circRNAs were predicted using miRanda software, and were further analyzed combining DIANA-miRPath v.3 platform (Reverse Search module) with KEGG pathways of COLORECTAL CANCER and MicroRNAs in cancer (Entry: map05210 and map05206). CircRNA-miRNA interaction networks were constructed using Cytoscape software. Expression levels of a significantly down-regulated circRNA, circDDX17 (hsa_circ_0002211), was detected by qRT-PCR in 60 paired CRC tissues. CircDDX17 was knockdown by siRNA, and the biological functions of circDDX17 were examined in CRC cell lines.

Results

Totally 448 differentially expressed circRNAs were identified, including 394 up-regulated and 54 down-regulated circRNAs. qRT-PCR validation confirmed the reliability of the RNA-Seq data. GO and KEGG analyses revealed that these dysregulated circRNAs were potentially implicated in CRC pathogenesis. Analyses by combining miRanda and miRPath softwares with KEGG pathways suggested that the miRNAs targeted by the top 10 dysregulated circRNAs were associated with the KEGG pathways of COLORECTAL CANCER and MicroRNAs in cancer, indicating that circRNA-miRNA interactions might play important functional roles in the initiation and progression of CRC. The results of qRT-PCR for circDDX17 in 60 paired CRC tissues showed that circDDX17 was significantly down-regulated in CRC tissues and associated with unfavorable clinicopathological parameters. In vitro experiments showed that silencing of circDDX17 promoted CRC cell proliferation, migration, invasion, and inhibited apoptosis.

Conclusions

In conclusion, we have identified numerous circRNAs that are dysregulated in CRC tissues compared with adjacent normal mucosa tissues. Bioinformatic analyses suggested that these dysregulated circRNAs might play important functional roles in CRC tumorigenesis. CircDDX17 functions as a tumor suppressor and could serve as a potential biomarker and a therapeutic target for CRC.

Electronic supplementary material

The online version of this article (10.1186/s13046-018-1006-x) contains supplementary material, which is available to authorized users.

miRNA-185 regulates retained fetal membranes of cattle by targeting STIM1

Retained fetal membranes (RFM) of cows is an important reproductive disturbance, and is related to miRNA-185. Stromal interaction molecule 1 (STIM1), a potential target gene of miRNA-185, could influence placenta release via regulating Ca²⁺ concentration intracellular. The aim of this study was to explore the mechanism of RFM by investigating the regulatory relationship between miRNA-185 and STIM1 in primary uterine caruncel epithelial (UCE) cells. Serum samples of healthy Holstein dairy cows (n = 20) and RFM cows (n = 12), with a similar age, parity, weight, and milk yield, were collected to detect Ca²⁺ concentration at prepartum 1-5 d and postpartum 6, 12 and 24 h. Caruncle tissues were collected from healthy (n = 6) and RFM cows (n = 6) at 12 h after calving. Quantitative polymerase chain reaction (Q-PCR) and western blotting (WB) were performed to detect the mRNA and protein levels of STIM1, respectively. UCE cells were cultured by the explant culture method, further purified, and subsequently treated with PmirGLO-STIM1-Mut + miRNA-185 mimics and mirGLO-STIM1-Mut + miRNA-185 NC. Q-PCR and WB were performed to detect mRNA and protein levels of STIM1 with treated miRNA-185 mimics. Serum levels of Ca²⁺ from RFM cows were abnormally decreased at prepartum 1 d and postpartum 6, 12 and 24 h. Expression level of STIM1 was down-regulated in the caruncle tissue of RFM cows. The luciferase activity was decresed about 30.9% by miRNA-185 mimics (p < 0.01), and the mRNA and protein levels of STIM1 were downregulated miRNA-185-mimics. It was suggesting that miRNA-185 might play an important role in RFM through regulating the expression of STIM1.

Preliminary Outcome of Individualized Abdominoperineal Excision for Locally Advanced Low Rectal Cancer

Background:

The introduction of individualized abdominoperineal excision (APE) may minimize operative trauma and reduce the rate of complications. The purpose of this study was to evaluate the safety and efficacy of individualized APE for low rectal cancer.

Methods:

Fifty-six patients who underwent individualized APE from June 2011 to June 2015 were evaluated retrospectively in Beijing Chaoyang Hospital, Capital Medical University. The main outcome measures were circumferential resection margin (CRM) involvement, intraoperative perforation, postoperative complications, and local recurrence. Statistical analysis was performed using SPSS version 16.0.

Results:

Fifty (89%) patients received preoperative chemoradiotherapy: 51 (91%) patients were treated with the sacrococcyx preserved; 27 (48%) patients with the levator ani muscle partially preserved bilaterally; 20 (36%) patients with the levator ani muscle partially preserved unilaterally and the muscle on the opposite side totally preserved; 7 (13%) patients with intact levator ani muscle and part of the ischioanal fat bilaterally dissected; and 2 (4%) patients with part of the ischioanal fat and intact lavator ani muscle dissected unilaterally and the muscle on the opposite side partially preserved. The most common complications included sexual dysfunction (12%), perineal wound complications (13%), urinary retention (7%), and chronic perineal pain (5%). A positive CRM was demonstrated in 3 (5%) patients, and intraoperative perforations occurred in 2 (4%) patients. On multiple logistic regression analysis, longer operative time (P = 0.032) and more intraoperative blood loss (P = 0.006) were significantly associated with perineal procedure-related complications. The local recurrence was 4% at a median follow-up of 53 months (range: 30–74 months).

Conclusion:

With preoperative chemoradiotherapy, individualized APE may be a relatively safe and feasible approach for low rectal cancer with acceptable oncological outcomes.

Selective precipitation and characterization of lignin-carbohydrate complexes (LCCs) from Eucalyptus

Six types of lignin-carbohydrate complex (LCC) fractions were isolated from Eucalyptus. The acidic dioxane treatment applied significantly improved the yield of LCCs. The extraction conditions had a limited impact on the LCC structures and linkages. Characterization of the lignin-carbohydrate complex (LCC) structures and linkages promises to offer insight on plant cell wall chemistry. In this case, Eucalyptus LCCs were extracted by aqueous dioxane, and then precipitated sequentially by 70% ethanol, 100% ethanol, and acidic water (pH = 2). The composition and structure of the six LCC fractions obtained by selective precipitation were investigated by sugar analysis, molecular weight determination, and 2D HSQC NMR. It was found that the acidic (0.05-M HCl) dioxane treatment significantly improved the yield of LCCs (66.4% based on Klason lignin), which was higher than the neutral aqueous dioxane extraction, and the extraction condition showed limited impact on the LCC structures and linkages. In the fractionation process, the low-molecular-weight LCCs containing a high content of carbohydrates (60.3-63.2%) were first precipitated by 70% ethanol from the extractable solution. The phenyl glycoside (PhGlc) bonds (13.0-17.0 per 100Ar) and highly acetylated xylans were observed in the fractions recovered by the precipitation with 100% ethanol. On the other hand, such xylan-rich LCCs exhibited the highest frequency of β-O-4 linkages. The benzyl ether (BE) bonds were only detected in the fractions obtained by acidic water precipitation.

[Molecular typing characterization of food-borne methicillin-resistant Staphylococcus aureus in China]

Objective: To analyses the antimicrobial resistance and molecular characterization of 21 MRSA isolates cultured from retail foods from different provinces in China, and evaluate the molecular typing methods. Methods: Twenty-one MRSA isolates were obtained from national foodborne pathogen surveillance network in 2012 (Chinese salad, n=3; milk, n=1; cake, n=2; rice, n=1; cold noodle, n=1; spiced beef, n=1; dumpling, n=1; packed meal, n=1; salad, n=1; raw pork, n=9). The antimicrobial resistance of 21 strains to 12 antimicrobial agents was tested by broth dilution method. Polymerase chain reaction (PCR) and DNA sequencing were performed to obtain the genetic types of MLST (ST) and spa typing. The clonal complex (CC) was assigned by eBURST soft and the MLVA type (MT) and MLVA complex (MC) were identified via the database of the MLVA website (http://www.mlva.net). SmaI pulsed-field gel electrophoresis (SmaⅠ-PFGE) was also carried out to obtain the PFGE patterns of 21 strains. The genetic diversity and discriminatory power of typing were calculated by the Simpson's index of diversity (diversity index, DI) to find out the best genotyping method for MRSA. Results: All MRSA isolates showed multi-drug resistance(MDR), and were resistant to oxacillin, benzylpenicillin, clindamycin and erythromycin, and 71.4% (15/21), 47.6% (10/21), 42.9% (9/21) and 28.6% (6/21) of the MRSA isolates were resistant to tetracycline, ciprofloxacin, trimethoprim/sulfamethoxazole and gentamicin, respectively. Moreover, one strain was found to be resistant to all three antimicrobials of levofloxacin, moxifloxacin and rifampicin. Great diversity was found in these food-associated MRSA (6 STs, 7 spa types, and 9 MTs). PFGE patterns were more diverse than those of other three molecular typing methods (19 pulse types). The index of diversity (DI) of PFGE, MLVA, spa typing and MLST was 0.99, 0.80, 0.73, and 0.61, respectively. Among the MRSA isolates, CC9-ST9-t899-MT929-MC2236 (PFGE Cluster Ⅴ) was the most prevalent clone, which were all cultured from raw pork (9 isolates). Besides, two MRSA were identified as CC59-ST338-t437-MT621-MC621 (PFGE Cluster Ⅳ). Different clone had their own resistance spectrum profiles. Conclusion: The food-borne MRSA isolates were all MDR in this study. Different clones had their own resistance spectrum profiles. MLVA represented a promising tool for molecular epidemiology tracing of MRSA in foodborne disease events.

Fractionation of rapeseed straw by hydrothermal/dilute acid pretreatment combined with alkali post-treatment for improving its enzymatic hydrolysis

The aim of the research was to evaluate the effect of combined treatments on fermentable sugar production from rapeseed straw. An optimum condition was found to be the combination of hydrothermal pretreatment at 180°C for 45min and post-treatment by 2% NaOH at 100°C for 2h, which was based on the quantity of monosaccharides released during enzymatic hydrolysis. As compared with the raw material without treatment, the combination of hydrothermal pretreatment and alkali post-treatment resulted in a significant increase of the saccharification rate by 5.9times. This process potentially turned rapeseed straw into value added products in accordance with the biorefinery concept.

MicroRNA 192 regulates chemo-resistance of lung adenocarcinoma for gemcitabine and cisplatin combined therapy by targeting Bcl-2

Lung cancer is the most leading cause of cancer-related death worldwide, with non-small-cell lung cancer (NSCLC) accounting for over 80% of all lung cancer cases. Patients with NSCLC are mostly treated with platinum-based chemotherapy. Chemoresistance is a leading cause of chemo-therapy failure in NSCLC treatment. Recent studies have shown that dysregulation of microRNAs might modulate the resistance of cancer cells to anti-cancer drugs, yet the modulation mechanism is not fully understood. In this paper, we try to test whether miR-192 regulates chemo-resistance in human carcinoma A549 mice model by targeting Bcl-2. Mice model of human lung adenocarcinoma was built up, and was used for gemcitabine and cisplatin combined chemotherapy. MTT assay, real-time RT-PCR, western blotting assay were used to investigate miR-192 expression levels, cell viability ratio and Bcl-2 protein expression levels. MiR-192 expression level in A549 cells is significantly higher than in normal human bronchial epithelial cells. MiR-192 inhibitor treated tumor exhibits sensitivity to cisplatin and gemcitabine therapy. Bcl-2 mRNA and protein expression levels up-regulated in miR-192 inhibitor treated tumor. Bcl-2 is a key regulator for miR-192 related chemotherapy resistance. In this study, we demonstrate that miR-192 regulates chemoresistance for gemcitabine and cisplatin combined chemotherapy in human adenocarcinoma lung cancer A549 cells, and Bcl-2 is the target of miR-192.

Percutaneous radiologic gastrostomy via nasopharyngeal intubation for the treatment of patients with complete malignant pharyngoesophageal obstruction

BACKGROUND/AIMS

For patients with complete malignant pharyngoesophageal obstruction (CMPO), percutaneous radiologic gastrostomy (PRG) under ultrasound/CT guidance can complicate it to cause failure due to unsatisfied stomach filling. In this study, we retrospectively investigated whether PRG via nasopharyngeal intubation is feasible and effective for these patients.

METHODOLOGY

PRG via nasopharyngeal intubation was attempted in 21 patients with CMPO (mean 70.8 ± 8.23 years). The technique comprised a dilation of the stomach via nasopharyngeal intubation using a catheter, followed by fluoroscopically guided puncture and gastrostomy tube placement. Complications including hemorrhage, peritonitis, gastrojejunocolic fistula, infection of puncture site, tube blocking and outleakage was observed during and after the procedure.

RESULTS

A 5F catheter was successfully inserted to the stomach under fluoroscopical guidance and subsequent PRG was performed in all 21 patients. Minor complications occurred in 14.3% patients including mild infection of the fistula in 1, tube blocking in 1 and unexpected tube drawing out in 1. Follow-up nutrition indexes revealed obvious improved nutrition compared to before PRG (P < 0.05).

CONCLUSION

PRG via nasopharyngeal intubation was simple, feasible and effective for patients with CMPO.

Ligation of the intersphincteric fistula tract plus a bioprosthetic anal fistula plug (LIFT-Plug): a new technique for fistula-in-ano

AIM

Ligation of the intersphincteric fistula tract and reinforcement with a bioprosthetic graft are two recently reported procedures that have shown promise in the treatment of anal fistula. This study was undertaken to validate combining ligation of the intersphincteric fistula tract plus bioprosthetic anal fistula plug and report our preliminary results and experience.

METHOD

Twenty-one patients with transsphincteric anal fistula were treated with ligation of the intersphincteric fistula tract plus concurrent bioprosthetic plug of the anal fistula. We evaluated healing time, fistula closure rate and postoperative anal function according to the Wexner continence score.

RESULTS

No mortality or major complications were observed. Median operative time was 20 (range 15-40) min. After a median follow-up of 14 (range 12-15) months, the overall success rate was 95% (20/21), with a median healing time of 2 (range 2-3) weeks for external anal fistula opening and 4 (range 3-7) weeks for intersphincteric groove incision. Only 1 (5%) patient reported rare incontinence for gas postoperatively (Wexner score 1).

CONCLUSIONS

Ligation of the intersphincteric fistula tract plus a bioprosthetic anal fistula plug is an easy, safe, effective and useful alternative in the management of anal fistula. Further randomized controlled studies are necessary to better evaluate long-term results.

CXCR4/SDF-1 axis is involved in lymph node metastasis of gastric carcinoma

AIM: To investigate the role of CXC chemokine receptor-4 (CXCR4) and stromal cell-derived factor-1 (SDF-1) in lymph node metastasis of gastric carcinoma.

METHODS: In 40 cases of gastric cancer, expression of CXCR4 mRNA in cancer and normal mucous membrane and SDF-1 mRNA in lymph nodes around the stomach was detected using quantitative polymerase chain reaction (PCR) (TaqMan) and immunohistochemistric assay. SGC-7901 and MGC80-3 cancer cells were used to investigate the effect of SDF-1 on cell proliferation and migration.

RESULTS: Quantitative reverse transcription PCR and immunohistochemistry revealed that the expression level of CXCR4 in gastric cancer was significantly higher than that in normal mucous membrane (1.6244 ± 1.3801 vs 1.0715 ± 0.5243, P < 0.05). The expression level of CXCR4 mRNA in gastric cancer with lymph node metastasis was also significantly higher than that without lymph node metastasis (0.823 ± 0.551 vs 0.392 ± 0.338, P < 0.05). CXCR4 expression was significantly related to poorly differentiated, high tumor stage and lymph node metastasis. Significant differences in the expression level of SDF-1 mRNA were found between lymph nodes in metastatic gastric cancer and normal nodes (0.5432 ± 0.4907 vs 0.2640 ± 0.2601, P < 0.05). The positive expression of SDF-1 mRNA in lymph nodes of metastatic gastric cancer was consistent with the positive expression of CXCR4 mRNA in gastric cancer (r = 0.776, P < 0.01). Additionally, human gastric cancer cell lines expressed CXCR4 and showed vigorous proliferation and migratory responses to SDF-1. AMD3100 (a specific CXCR4 antagonist) was also found to effectively reduce the migration of gastric cancer cells.

CONCLUSION: The CXCR4/SDF-1 axis is involved in the lymph node metastasis of gastric cancer. CXCR4 is considered as a potential therapeutic target in the treatment of gastric cancer.

Adipose-derived stem cells promote gastric cancer cell growth, migration and invasion through SDF-1/CXCR4 axis

BACKGROUND/AIMS

The CXCR4/SDF-1 axis regulates the trafficking of various cell types. In the study we investigated whether adipose-derived stem cells can promote gastric cancer cell growth and migration through SDF-1/CXCR4 axis.

METHODOLOGY

The expression of CXCR4 in gastric cancer cell line MGC-803 and SDF-1 in Adipose-derived stem cells was detected by using PCR method. Furthermore, cell proliferation, migration and invasion assays were examined and inhibitors of CXCR4 were used to determine the effect on cell migration.

RESULTS

The cells isolated from subcutaneous adipose tissue show characteristics of stem cells. Gastric cancer cells express CXCR4 and Adipose-derived stem cells express SDF-1. Additionally, the tumor cells showed vigorous proliferative and migratory responses to ADSCs. AMD3100 can effectively reduce the migration of gastric cancer cells.

CONCLUSIONS

Adipose-derived stem cells can promote gastric cancer cell growth, migration and invasion through SDF-1/CXCR4 axis. CXCR4 can be used in the treatment of gastric cancer as a potential therapeutic target.

Application of acellular dermal matrix for intestinal elongation in animal models

AIM: To investigate the efficacy of acellular dermal matrix (ADM) for intestinal elongation in animal models.

METHODS: Japanese white big-ear rabbits (n = 9) and Wuzhishan miniature pigs (n = 5) were used in the study. Home-made and commercial ADM materials were used as grafts, respectively. A 3-cm long graft was interposed in continuity with the small bowel and a side-to-side anastomosis, distal to the graft about 3-4 cm, was performed. The animals were sacrificed at 2 wk, 4 wk, 8 wk and 3 mo after surgery and the histological changes were evaluated under light microscope and electron microscope.

RESULTS: The animals survived after the operation with no evidence of peritonitis and sepsis. Severe adhesions were found between the graft and surrounding intestine. The grafts were completely absorbed within postoperative two or three months except one. Histological observation showed inflammation in the grafts with fibrinoid necroses, infiltration of a large amount of neutrophils and leukomonocytes, and the degree varied in different stages. The neointestine with well-formed structures was not observed in the study.

CONCLUSION: It is not suitable to use acellular dermal matrix alone as a scaffold for the intestinal elongation in animal models.

Cloning, expression and identification of the gene of human single-chain variable fragment antibody against Hepatitis B virus surface antigen

Expression of single-chain variable fragment (scFv) antibodies on the surface of bacteriophage is widely used to prepare antibodies with pre-defined specificities. A phage antibody library containing the gene for scFv antibody against Hepatitis B virus surface antigen (HBsAg) was panned with HBsAg immobilized on microtiter plate wells. After five rounds of panning 30 phage clones specific to HBsAg were obtained and one selected clone was sequenced. It was found to consist of 789 bp and its amino acid sequence and specifically detected the respective antigen in the patients but not in healthy persons.

[Comparative studies of mitochondrial DNA of T-type cytoplasmic male sterile lines and their maintainers in wheat]

mtDNAs of T type wheat cytoplasmic male sterile lines 75-3369A and their maintainers 75-3369B were isolated and digested completely with restriction endonuclease BamH I, EcoR I, Hind III. The mitochondrial genomic difference between CMS line and maintainers were revealed by Southern hybridization with probes of atp6 from Oenothera and nad3/rps12, cox I from wheat mitochondria. Southern hybridization showed the differences between these two lines. Discussion was made on the change of the DNA composition and the male sterile cytoplasm.

[Detection of apoptosis by in situ labeling and study on the expression of PCNA in hypertrophic scars and keloids]

To investigate the involvement of apoptosis and proliferation in the lesions of hypertrophic scars and keloids, eighteen samples of hypertrophic scar and five samples of keloid were collected. The apoptosis was detected with terminal deoxynucleatidyl transferase mediated d-UTP biotin nick end labeling(TUNEL) and the expression of PCNA was assessed with immunohistochemical technique in scar lesions and normal skin. Results showed that in hypertrophic scar and keloid samples the rate of proliferating cells in dermis was higher than that of normal skin(P < 0.05), whereas the apoptosis index between scars and normal skin shows no statistical significance. It indicates that excessive proliferation and the lack of apoptosis of cells in dermis may cause the formation and development of hypertrophic scars and keloids.