Genome-wide CNV analysis reveals candidate genes associated with milk production traits in water buffalo (Bubalus bubalis).

Buffaloes are vital contributors to the global dairy industry. Understanding the genetic basis of milk production traits in buffalo populations is essential for breeding programs and improving productivity. In this study, we conducted whole-genome resequencing on 387 buffalo genomes from 29 diverse Asian breeds, including 132 river buffaloes, 129 swamp buffaloes, and 126 crossbred buffaloes. We identified 36,548 copy number variant (CNVs) spanning 133.29 Mb of the buffalo genome, resulting in 2,100 copy number variant regions (CNVRs), with 1,993 shared CNVRs being found within the studied buffalo types. Analyzing CNVRs highlighted distinct genetic differentiation between river and swamp buffalo subspecies, verified by evolutionary tree and principal component analyses. Admixture analysis grouped buffaloes into river and swamp categories, with crossbred buffaloes displaying mixed ancestry. To identify candidate genes associated with milk production traits, we employed 3 approaches. First, we used Vst-based population differentiation, revealing 11 genes within CNVRs that exhibited significant divergence between different buffalo breeds, including genes linked to milk production traits. Second, expression quantitative loci (eQTL) analysis revealed differential expression of CNVR-driven genes (DECGs) associated with milk production traits. Notably, known milk production-related genes were among these DECGs, validating their relevance. Last, a genome-wide association study (GWAS) identified 3 CNVRs significantly linked to peak milk yield. Our study provides comprehensive genomic insights into buffalo populations and identifies candidate genes associated with milk production traits. These findings facilitate genetic breeding programs aimed at increasing milk yield and improving quality in this economically important livestock species.

Extended procedure has no oncological benefits over segmental resection in the treatment of non-metastatic splenic flexure colon cancer, a population-based cohort study and a single center's decade-long experience.

To compare the oncological survival outcome between extended resections (ER) and segmental resection (SR) for non-metastatic splenic flexure tumors. A total of 10,063 splenic flexure colon cancers patients who underwent ER (n = 5546) or SR (n = 4517) from 2010 to 2018 were included from the Surveillance, Epidemiology, and End Results (SEER)-registered database. Additionally, we included 135 patients from our center who underwent ER (n = 54) or SR (n = 81) between 2011 and 2021. Survival rates were compared between groups. To reduce the inherent bias of retrospective studies, propensity score matching (PSM) analysis was performed. In the SEER database, patients in the ER group exhibited higher pT stage, pN stage, larger tumor size, and elevated rates of CEA level, perineural invasion, and tumor deposits compared to those in the SR group (each P < 0.05). The 5-year cancer-specific survival (CSS) rate was slightly lower in the ER group than in the SR group (79.2% vs. 81.6%, P = 0.002), while the 5-year overall survival (OS) rates were comparable between the two groups (66.2% vs. 66.9%, P = 0.513). After performing PSM, both the 5-year CSS and 5-year OS rates were comparable between the ER and SR groups (5-year CSS: 84.9% vs. 83.0%, P = 0.577; 5-year OS: 70.6% vs. 66.0%, P = 0.415). These findings were consistent in the subgroup analysis that included only patients with stage III disease or tumor size ≥ 7 cm. Furthermore, although the number of harvested lymph nodes was higher in the ER group compared to the SR group (14.4 vs. 12.7, P < 0.001), the number of invaded lymph nodes remained similar between the two groups (0.5 vs. 0.5, P = 0.90). Similarly, our center's data revealed comparable 3-year OS and 3-year disease-free survival (DFS) rates between the two groups. ER have no significant oncological benefits over SR in the treatment of non-metastatic splenic flexure colon cancer, even for locally advanced cases.

Unraveling variations and enhancing prediction of successful sphincter-preserving resection for low rectal cancer: A post hoc analysis of the multicenter LASRE randomized clinical trial.

BACKGROUND: Accurate prediction of successful sphincter-preserving resection (SSPR) for low rectal cancer enables peer institutions to scrutinize their own performance and potentially avoid unnecessary permanent colostomy. The aim of this study is to evaluate the variation in SSPR and present the first artificial intelligence (AI) models to predict SSPR in low rectal cancer patients. STUDY DESIGN: This was a retrospective post hoc analysis of a multicenter, noninferiority randomized clinical trial (LASRE, NCT XXXXXX) conducted in 22 tertiary hospitals across China. A total of 604 patients who underwent neoadjuvant chemoradiotherapy (CRT) followed by radical resection of low rectal cancer were included as the study cohort, which was then split into a training set (67%) and a testing set (33%). The primary end point of this post hoc analysis was SSPR, which was defined as meeting all the following criteria: (1) sphincter-preserving resection; (2) complete or nearly complete TME, (3) a clear CRM (distance between margin and tumor of 1 mm or more), and (4) a clear DRM (distance between margin and tumor of 1 mm or more). Seven AI algorithms, namely, support vector machine (SVM), logistic regression (LR), extreme gradient boosting (XGB), light gradient boosting (LGB), decision tree classifier (DTC), random forest (RF) classifier, and multilayer perceptron (MLP), were employed to construct predictive models for SSPR. Evaluation of accuracy in the independent testing set included measures of discrimination, calibration, and clinical applicability. RESULTS: The SSPR rate for the entire cohort was 71.9% (434/604 patients). Significant variation in the rate of SSPR, ranging from 37.7% to 94.4%, was observed among the hospitals. The optimal set of selected features included tumor distance from the anal verge before and after CRT, the occurrence of clinical T downstaging, post-CRT weight and clinical N stage measured by magnetic resonance imaging. The 7 different AI algorithms were developed and applied to the independent testing set. The LR, LGB, MLP and XGB models showed excellent discrimination with AUROC values of 0.825, 0.819, 0.819 and 0.805, respectively. The DTC, RF and SVM models had acceptable discrimination with AUROC values of 0.797, 0.766 and 0.744, respectively. LR and LGB showed the best discrimination, and all 7 AI models had superior overall net benefits within the range of 0.3-0.8 threshold probabilities. Finally, we developed an online calculator based on the LGB model to facilitate clinical use. CONCLUSIONS: The rate of SSPR exhibits substantial variation, and the application of AI models has demonstrated the ability to predict SSPR for low rectal cancers with commendable accuracy.

Transcriptome-Wide Association Study Reveals Potentially Candidate Genes Responsible for Milk Production Traits in Buffalo.

Identifying key causal genes is critical for unraveling the genetic basis of complex economic traits, yet it remains a formidable challenge. The advent of large-scale sequencing data and computational algorithms, such as transcriptome-wide association studies (TWASs), offers a promising avenue for identifying potential causal genes. In this study, we harnessed the power of TWAS to identify genes potentially responsible for milk production traits, including daily milk yield (MY), fat percentage (FP), and protein percentage (PP), within a cohort of 100 buffaloes. Our approach began by generating the genotype and expression profiles for these 100 buffaloes through whole-genome resequencing and RNA sequencing, respectively. Through comprehensive genome-wide association studies (GWAS), we pinpointed a total of seven and four single nucleotide polymorphisms (SNPs) significantly associated with MY and FP traits, respectively. By using TWAS, we identified 55, 71, and 101 genes as significant signals for MY, FP, and PP traits, respectively. To delve deeper, we conducted protein-protein interaction (PPI) analysis, revealing the categorization of these genes into distinct PPI networks. Interestingly, several TWAS-identified genes within the PPI network played a vital role in milk performance. These findings open new avenues for identifying potentially causal genes underlying important traits, thereby offering invaluable insights for genomics and breeding in buffalo populations.

Morphology of the anterior mesorectum: a new predictor for local recurrence in patients with rectal cancer.

BACKGROUND: Pre-operative assessment with high-resolution magnetic resonance imaging (MRI) is useful for assessing the risk of local recurrence (LR) and survival in rectal cancer. However, few studies have explored the clinical importance of the morphology of the anterior mesorectum, especially in patients with anterior cancer. Hence, the study aimed to investigate the impact of the morphology of the anterior mesorectum on LR in patients with primary rectal cancer. METHODS: A retrospective study was performed on 176 patients who underwent neoadjuvant treatment and curative-intent surgery. Patients were divided into two groups according to the morphology of the anterior mesorectum on sagittal MRI: (1) linear type: the anterior mesorectum was thin and linear; and (2) triangular type: the anterior mesorectum was thick and had a unique triangular shape. Clinicopathological and LR data were compared between patients with linear type anterior mesorectal morphology and patients with triangular type anterior mesorectal morphology. RESULTS: Morphometric analysis showed that 90 (51.1%) patients had linear type anterior mesorectal morphology, while 86 (48.9%) had triangular type anterior mesorectal morphology. Compared to triangular type anterior mesorectal morphology, linear type anterior mesorectal morphology was more common in females and was associated with a higher risk of circumferential resection margin involvement measured by MRI (35.6% [32/90] vs . 16.3% [14/86], P   =  0.004) and a higher 5-year LR rate (12.2% vs . 3.5%, P   =  0.030). In addition, the combination of linear type anterior mesorectal morphology and anterior tumors was confirmed as an independent risk factor for LR (odds ratio = 4.283, P  = 0.014). CONCLUSIONS: The classification established in this study was a simple way to describe morphological characteristics of the anterior mesorectum. The combination of linear type anterior mesorectal morphology and anterior tumors was an independent risk factor for LR and may act as a tool to assist with LR risk stratification and treatment selection.

Development and validation of artificial intelligence models for preoperative prediction of inferior mesenteric artery lymph nodes metastasis in left colon and rectal cancer.

BACKGROUND: Dissection of lymph nodes at the roots of the inferior mesenteric artery (IMAN) should be offered only to selected patients at a major risk of developing IMAN involvement. The aim of this study is to present the first artificial intelligence (AI) models to predict IMAN metastasis risk in the left colon and rectal cancer patients. METHODS: A total of 2891 patients with descending colon including splenic flexure, sigmoid colon and rectal cancer undergoing major primary surgery and IMAN dissection were included as a study cohort, which was then split into a training set (67%) and a testing set (33%). Feature selection was conducted using the least absolute shrinkage and selection operator (LASSO) regression model. Seven AI algorithms, namely Support Vector Machine (SVM), Logistic Regression (LR), Extreme Gradient Boosting (XGB), Light Gradient Boosting (LGB), Decision Tree Classifier (DTC), Random Forest (RF) classifier, and Multilayer Perceptron (MLP), as well as traditional multivariate LR model were employed to construct predictive models. The optimal hyperparameters were determined with 5 fold cross-validation. The predictive performance of models and the expert surgeon was assessed and compared in the testing set independently. RESULTS: The IMAN involvement incidence was 4.6%. The optimal set of features selected by LASSO included 10 characteristics: neoadjuvant treatment, age, synchronous liver metastasis, synchronous lung metastasis, signet ring adenocarcinoma, neural invasion, lymphovascular invasion, CA199, endoscopic obstruction, T stage evaluated by MRI. The most accurate model derived from MLP showed excellent prediction power with area under the receiver operating characteristic curve (AUROC) of 0.873 and produced 81.0% recognition sensitivity and 82.5% specificity in the testing set independently. In contrast, the judgment of IMAN metastasis by expert surgeon yield rather imprecise and unreliable results with a significantly lower AUROC of 0.509. Additionally, the proposed MLP had the highest net benefits and the largest reduction of unnecessary IMAN dissection without the cost of additional involved IMAN missed. CONCLUSION: MLP model was able to maintain its prediction accuracy in the testing set better than other models and expert surgeons. Our MLP model could be used to help identify IMA nodal metastasis and to select candidates for individual IMAN dissection.

Novel Insight into the Potential Role of Acylglycerophosphate Acyltransferases Family Members on Triacylglycerols Synthesis in Buffalo.

Acylglycerophosphate acyltransferases (AGPATs) are the rate-limiting enzymes for the de novo pathway of triacylglycerols (TAG) synthesis. Although AGPATs have been extensively explored by evolution, expression and functional studies, little is known on functional characterization of how many members of the AGPAT family are involved in TAG synthesis and their impact on the cell proliferation and apoptosis. Here, 13 AGPAT genes in buffalo were identified, of which 12 AGPAT gene pairs were orthologous between buffalo and cattle. Comparative transcriptomic analysis and real-time quantitative reverse transcription PCR (qRT-PCR) further showed that both AGPAT1 and AGPAT6 were highly expressed in milk samples of buffalo and cattle during lactation. Knockdown of AGPAT1 or AGPAT6 significantly decreased the TAG content of buffalo mammary epithelial cells (BuMECs) and bovine mammary epithelial cells (BoMECs) by regulating lipogenic gene expression (p < 0.05). Knockdown of AGPAT1 or AGPAT6 inhibited proliferation and apoptosis of BuMECs through the expression of marker genes associated with the proliferation and apoptosis (p < 0.05). Our data confirmed that both AGPAT1 and AGPAT6 could regulate TAG synthesis and growth of mammary epithelial cells in buffalo. These findings will have important implications for understanding the role of the AGPAT gene in buffalo milk performance.

Effect of partial preservation versus complete preservation of Denonvilliers' fascia on postoperative urogenital function in male patients with low rectal cancer (PREDICTION): protocol of a multicentre, prospective, randomised controlled clinical trial.

INTRODUCTION: Total mesorectal excision (TME) has been the gold standard for the surgical treatment of mid-low rectal cancer, but traditional TME removal of Denonvilliers' fascia (DVF) is too low and is prone to damage the connecting branches of the bilateral neurovascular bundles, which can lead to posturogenital dysfunction. A recently published multicenter randomised controlled trial revealed that TME with complete preservation of DVF (CP-DVF) has protective effects on postoperative urogenital function for male patients with rectal cancer with specific staging and location (preoperative staging T1-4N0-2M0, but T1-2 for anterior rectal wall). Our previous studies have confirmed that TME with partial preservation of DVF (PP-DVF) could also achieve satisfactory results regardless of the circumferential location of the tumour. However, there is a lack of randomised controlled trials to prove that the efficacy of TME with PP-DVF is equivalent to that with CP-DVF with respect to postoperative urogenital function. METHODS AND ANALYSIS: This study is a prospective, multicentre, equivalent design, open-label randomised clinical trial in which 278 male patients with low rectal cancer will be recruited from 11 large-scale gastrointestinal medical centres in China. Patients will be randomly assigned to undergo PP-DVF or CP-DVF. We will test the hypothesis that PP-DVF is similar to CP-DVF with respect to sexual function at postoperative month 12 (5-item version of the International Erectile Function Index Questionnaire and ejaculation function classification). The secondary outcomes include the assessment of urinary function, surgical safety and oncological outcomes. ETHICS AND DISSEMINATION: This trial has been approved by the Institutional Review Board of Fujian Medical University Union Hospital (2020YF016-01) and is filed on record by all other centres. Written informed consent will be obtained from all eligible participants before enrolment. The trial's results will be disseminated via peer-reviewed scientific journals and conference presentations. TRIAL REGISTRATION NUMBER: ChiCTR2000034892.

Apelin and Apelin Receptor in Follicular Granulosa Cells of Buffalo Ovaries: Expression and Regulation of Steroidogenesis.

Apelin (APLN), as a ligand for APJ (an orphan G-protein-coupled receptor), is an adipokine with pleiotropic effects in many physiological processes of the body. It has an important role in the control of reproduction particularly in females (mainly in control of ovarian function). This study was carried out to investigate the mRNA and protein amounts of APLN/APJ in granulose cells (GCs) of ovarian follicles with small (SF), medium (MF), and large (LF) sizes of buffalo (Bubalus bubalis) and the effect of IGF1 and follicle-stimulating hormone (FSH) on the expression levels of APLN/APJ. In addition, we evaluated the effect of various doses of APLN (isoforms -13 and -17) singly or in combination with IGF1 and FSH on estradiol (E2) and progesterone (P4) secretion in GCs. The mRNA and protein abundance of APLN was the highest in GCs of LF while the APJ expression enhanced with follicle enlargement in GCs (p-value <0.01). IGF1 and FSH elevated the mRNA and protein amounts of APLN and FSH, and IGF1 increased the expression of APJ in buffalo GCs (p-value <0.01). Both isoforms of APLN (-13/-17) singly or in the presence of IGF1 or FSH increased the secretion of E2 and P4 with or without preincubation of cells with APJ antagonist (ML221 10 µM), although we had some variation in the effects. Concurrently, APLN-13/-17 significantly increased the mRNA and protein expression of CYP19A1 and StAR (p-value <0.01). ML221 substantially diminished the secretion of E2 and P4 and also the expression of CY19A1 and StAR in buffalo GCs (p-value <0.01). We also revealed that APLN-13/-17 (10-9 M), singly or in response to IGF1 and FSH, increased the production of E2 and P4 in different times of stimulation. In conclusion, APLN may play a crucial role in steroidogenesis and follicular development in ovarian GCs of buffalo.

Chylous ascites has a higher incidence after robotic surgery and is associated with poor recurrence-free survival after rectal cancer surgery.

BACKGROUND: Postoperative chylous ascites is an infrequent condition after colorectal surgery and is easily treatable. However, its effect on the long-term oncological prognosis is not well established. This study aimed to investigate the short-term and long-term impact of chylous ascites treated with neoadjuvant therapy followed by rectal cancer surgery and to evaluate the incidence of chylous ascites after different surgical approaches. METHODS: A total of 898 locally advanced rectal cancer patients treated with neoadjuvant chemoradiotherapy followed by surgery between January 2010 and December 2018 were included. The clinicopathological data and outcomes of the patients with chylous ascites were compared with those of the patients without chylous ascites. The primary endpoint was recurrence-free survival (RFS). To balance baseline confounders between groups, propensity score matching (PSM) was performed for each patient with a logistic regression model. RESULTS: Chylous ascites was detected in 3.8% (34/898) of the patients. The incidence of chylous ascites was highest after robotic surgery (6.9%, 6/86), followed by laparoscopic surgery (4.2%, 26/618) and open surgery (1.0%, 2/192, P = 0.021). The patients with chylous ascites had a significantly higher number of lymph nodes harvested (15.6 vs. 12.8, P = 0.009) and a 3-day longer postoperative hospital stay (P = 0.017). The 5-year RFS rate was 64.5% in the chylous ascites group, which was significantly lower than the rate in the no chylous ascites group (79.9%; P = 0.007). The results remained unchanged after PSM was performed. The chylous ascites group showed a nonsignificant trend towards a higher peritoneal metastasis risk (5.9% vs. 1.6%, P = 0.120). Univariate analysis and multivariate analysis confirmed chylous ascites (hazard ratio= 3.038, P < 0.001) as an independent negative prognostic factor for RFS. CONCLUSIONS: Considering the higher incidence of chylous ascites after laparoscopic and robotic surgery and its adverse prognosis, we recommend sufficient coagulation of the lymphatic tissue near the vessel origins, especially during minimally invasive surgery.

Impact of Surgical Approach on Surgical Resection Quality in Mid- and Low Rectal Cancer, A Bayesian Network Meta-Analysis.

AIM: To evaluate the evidence concerning the quality of surgical resection in laparoscopic (LapTME), robotic (RobTME) and transanal (TaTME) total mesorectal excision for mid-/low rectal cancer. METHODS: A systematic literature search of the PubMed, EMBASE and Cochrane Central Register of Controlled Trials databases was performed. A Bayesian network meta-analysis was utilized to compare surgical resection involved in these 3 surgical techniques by using ADDIS software. Rates of positive circumferential resection margins (CRMs) were the primary endpoint. RESULTS: A total of 34 articles, 2 randomized clinical trials (RCTs) and 32 non-RCTs, were included in this meta-analysis. Pooled data showed CRM positivity in 114 of 1763 LapTME procedures (6.5%), 54 of 1051 RobTME procedures (5.1%) and 60 of 1276 TaTME procedures (4.7%). There was no statistically significant difference among these 3 surgical approaches in terms of CRM involvement rates and all other surgical resection quality outcomes. The incomplete mesorectal excision rates were 9.6% (69/720) in the LapTME group, 1.9% (11/584) in the RobTME group and 5.6% (45/797) in the TaTME group. Pooled network analysis observed a higher but not statistically significant risk of incomplete mesorectum when comparing both LapTME with RobTME (OR = 1.99; 95% CI = 0.48-11.17) and LapTME with TaTME (OR = 1.90; 95% CI = 0.99-5.25). By comparison, RobTME was most likely to be ranked the best or second best in terms of CRM involvement, complete mesorectal excision, rate of distal resection margin (DRM) involvement and length of DRMs. In addition, RobTME achieved a greater mean tumor distance to the CRM than TaTME. It is worth noting that TaTME was most likely to be ranked the worst in terms of CRM involvement for intersphincteric resection of low rectal cancer. CONCLUSION: Overall, RobTME was most likely to be ranked the best in terms of the quality of surgical resection for the treatment of mid-/low rectal cancer. TaTME should be performed with caution in the treatment of low rectal cancer.

An Intrasheath Separation Technique for Nerve-Sparing High Ligation of the Inferior Mesenteric Artery in Colorectal Cancer Surgery.

PURPOSE: To investigate the relationship between the left trunk of the inferior mesenteric plexus (IMP) and the vascular sheath of the inferior mesenteric artery (IMA) and to explore anatomical evidence for autonomic nerve preservation during high ligation of the IMA in colorectal cancer surgery. METHODS: We evaluated the relationship in 23 consecutive cases of laparoscopic or robotic colorectal surgery with high ligation of the IMA at our institute. Anatomical dissection was performed on 5 formalin-fixed abdominal specimens. A novel anatomical evidence-based operative technique was proposed. RESULTS: Anatomical observation showed that the left trunk of the IMP was closely connected with the IMA and was involved in the composition of the vascular sheath. Based on anatomical evidence, we present a novel operative technique for nerve-sparing high ligation of the IMA that was successfully performed in 45 colorectal cancer surgeries with no intraoperative complications and satisfactory postoperative urogenital functional outcomes. CONCLUSION: The left trunk of the IMP is involved in the composition of the IMA vascular sheath. This novel anatomical evidence-based operative technique for nerve-sparing high ligation of the IMA is technically safe and feasible.

Individualized conditional survival nomograms for patients with locally advanced rectal cancer treated with neoadjuvant chemoradiotherapy and radical surgery.

BACKGROUND: Conditional survival (CS) considers the time already survived after surgery when estimating the survival probability, which may provide further useful prognostic information. OBJECTIVE: To evaluate CS in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (nCRT) and to create CS nomograms predicting the conditional probability of survival after proctectomy. METHODS: Consecutive patients with LARC who received nCRT followed by radical resection between 2011 and 2016 were identified. CS was defined as the probability of surviving y years after already surviving for x years. The formula used for CS was CS(x|y) = S(x + y)/S(x), where S(x) represents the survival at x years. Nomograms were constructed to predict the 5-year conditional overall survival (cOS) and conditional recurrence-free survival (cRFS). RESULTS: A total of 785 patients were included. The median follow-up time was 65.5 months. The probability of achieving 5-year survival after surgery for cancer increases with additional survival time. Maximum tumor diameter, distance from the anal verge, preoperative CA19-9 level, ypTNM stage and perineural invasion were independent predictors of OS, while maximum tumor diameter, distance from the anal verge, ypTNM stage and perineural invasion were independent risk factors for RFS. The nomograms predicted 5-year cOS and cRFS using these predictors and the time already survived. The online calculator can be accessed at http://www.rectalcancer.top/webcalculator. CONCLUSION: The proposed nomograms predict survival in patients after surgery, taking the time already survived into account.

Pelvimetric and Nutritional Factors Predicting Surgical Difficulty in Laparoscopic Resection for Rectal Cancer Following Preoperative Chemoradiotherapy.

AIM: Laparoscopic total mesorectal excision (LaTME) following preoperative chemoradiotherapy (PCRT) in locally advanced rectal cancer (LARC) is technically demanding. The present study is intended to evaluate predictive factors of surgical difficulty of LaTME following PCRT by using pelvimetric and nutritional factors. METHOD: Consecutive LARC patients receiving LaTME after PCRT were included. Surgical difficulty was classified based upon intraoperative (operation time, blood loss, and conversion) and postoperative outcomes (postoperative hospital stay and morbidities). Pelvimetry was performed using preoperative T2-weighted MRI. Nutritional factors such as albumin-to-globulin ratio (AGR) and prognostic nutritional index (PNI) were calculated. Multivariable logistic analysis was used to identify predictors of high surgical difficulty. A predictive nomogram was developed and validated internally. RESULTS: Among 294 patients included, 36 (12.4%) patients were graded as high surgical difficulty. Logistic regression analysis demonstrated that previous abdominal surgery (OR = 6.080, P = 0.001), tumor diameter (OR = 1.732, P = 0.003), intersphincteric resection (vs. low anterior resection, OR = 13.241, P < 0.001), interspinous distance (OR = 0.505, P = 0.009), and preoperative AGR (OR = 0.041, P = 0.024) were independently predictive of high surgical difficulty of LaTME after PCRT. Then, a predictive nomogram was built (C-index = 0.867). CONCLUSION: Besides previous abdominal surgery, type of surgery (intersphincteric resection), tumor diameter, and interspinous distance, we found that preoperative AGR could be useful for the prediction of surgical difficulty of LaTME after PCRT. A predictive nomogram for surgical difficulty may aid in planning an appropriate approach for rectal cancer surgery after PCRT.

Prognostic significance of carcinoembryonic antigen combined with carbohydrate antigen 19-9 following neoadjuvant chemoradiotherapy in patients with locally advanced rectal cancer.

AIM: The clinical significance of carcinoembryonic antigen (CEA) combined with carbohydrate antigen 19-9 (CA19-9) in patients with rectal cancer is not well established. The aim of this study was to determine the prognostic value of these combined tumour markers in patients with locally advanced rectal cancer (LARC) treated with neoadjuvant chemoradiotherapy (nCRT). METHOD: A total of 687 consecutive patients with LARC who underwent nCRT and radical surgery were analysed. Tumour characteristics, recurrence-free survival (RFS) and overall survival (OS) were compared according to the number of elevated tumour markers measured before and after nCRT. In addition, the prognostic significance of perioperative changes in the combined tumour markers was further evaluated. RESULT: The RFS and OS rates decreased in a stepwise manner in association with the number of elevated pre- and post-nCRT tumour markers (all p < 0.05). Multivariate analysis showed that only the number of elevated post-nCRT tumour markers was an independent prognostic factor (both p < 0.05). For 311 patients with elevated pre-nCRT tumour markers, normalization of the tumour markers after nCRT was an independent prognostic protective factor (both p < 0.05), and patients with both markers elevated post-nCRT had a 2.5- and 3.7-fold increased risk of recurrence and death, respectively (p < 0.05). Furthermore, normalization of post-nCRT tumour markers after surgery was also closely related to an improved prognosis. CONCLUSION: This combination of post-nCRT tumour markers can accurately predict the long-term survival of patients with LARC treated with nCRT and curative resection, and normalization of the combined tumour markers after either nCRT or surgery was associated with better survival.

Incidence of and Risk Factors for Gastroepiploic Lymph Node Involvement in Patients with Cancer of the Transverse Colon Including the Hepatic Flexure.

BACKGROUND: To define the incidence of gastroepiploic lymph node (GLN) metastasis in patients with cancer of the transverse colon, including the hepatic flexure, and to identify the preoperative predictors of GLN involvement in a large-volume center in China. METHODS: This retrospective monocentric cross-sectional study respected the STROBE statement. Of 3208 consecutive patients who underwent colon cancer resection, a total of 371 patients with cancer of the transverse colon including the hepatic flexure who underwent complete mesocolic excision and GLN resection in our center were retrospectively reviewed between November 2010 and November 2017. Logistic regression was performed to identify predictors of GLN metastasis. Endoscopic obstruction was defined as a luminal obstruction of the colon severe enough to prevent the colonoscope from passing beyond the tumor regardless of the presenting symptoms. RESULTS: The GLN involvement rate was 4.0 (2.0-6.1)%. Patients who had GLN involvement had a significantly higher rate of endoscopic obstruction (P = 0.030), higher rate of signet ring adenocarcinoma or lymphovascular invasion (P < 0.05), higher preoperative CEA level (P = 0.037), more advanced pN stage (P < 0.001) and more advanced M stage (P = 0.003) than the patients without GLN involvement. ROC curve analyses showed that the cutoff value for CEA was 17.0 ng/ml (46.7% sensitivity, 84.3% specificity, P = 0.037) for the prediction of GLN metastasis. Multivariate analysis showed that endoscopic obstruction, signet ring adenocarcinoma, a CEA level ≥17 ng/ml and M1 stage were independently correlated with the GLN metastasis. CONCLUSION: The incidence rate of GLN metastasis was low. To the best of our knowledge, the present study was the first to evaluate the preoperative predictors of GLN metastasis. Combinations of predictive factors may be useful for stratifying patients at high risk of GLN metastasis.

Timing to achieve the best recurrence-free survival after neoadjuvant chemoradiotherapy in locally advanced rectal cancer: experience in a large-volume center in China.

AIM: To identify the optimal interval from the end of neoadjuvant chemoradiotherapy to surgery (CRT-surgery interval) based on long-term oncological outcome of locally advanced rectal cancer (LARC). METHODS: Retrospective data analysis is reported from patients diagnosed with cT3 or T4 or TxN+ rectal cancer who underwent neoadjuvant treatment and curative-intent surgery between January 2010 and December 2018. With a priority focus on the effect of interval on oncological prognosis, we used recurrence-free survival (RFS) as the primary endpoint to determine the best cutoff point of time intervals. Then, the short-term and long-term outcomes of patients from longer and shorter interval groups were compared. RESULTS: Data from 910 patients were analyzed, with 185 patients who achieved pCR (20.3%). The trend for increased rates of pCR for groups with a prolonged time interval was not observed (P = 0.808). X-tile determined a cutoff value of 10.5 weeks, and the population was divided into longer (> 10 weeks) and shorter (≤ 10 weeks) interval groups. The shorter interval was associated with a higher wound infection rate (4.7% vs. 1.1%, P = 0.031), but other postoperative complications did not differ between the groups. The 5-year RFS rate was significantly higher in patients in a longer group than those in the shorter weeks group (86.8% vs. 77.8%, P = 0.016). The 5-year OS rates between groups were similar (84.1% vs. 82.5%, P = 0.257). Local recurrence and lung metastases rates were higher in shorter interval group than those of longer group (local recurrence rate: 1.7% vs. 5.1%, P = 0.049; lung metastases rate: 5.7% vs. 10.7%, P = 0.047). Cox multivariate regression analysis confirmed the CRT-surgery interval (HR = 0.599, P = 0.045) to be an independent prognostic factor of RFS. CONCLUSION: This study is the first, to the best of our knowledge, to define the optimal CRT-surgery interval based on RFS as the primary endpoint. Prolonging the waiting period to 10 weeks after the completion of CRT with additional chemotherapy cycles during the interval period might be a promising option to improve oncological survival in LARC patients treated with CRT and TME without compromising the surgical safety. Further randomized controlled trials investigating this are warranted to prove a clearly causality.

Lymph Node Regression to Neoadjuvant Chemoradiotherapy in Patients with Locally Advanced Rectal Cancer: Prognostic Implication and a Predictive Model.

AIM: Currently, few studies have focused on the prognostic impact of lymph node regression to neoadjuvant chemoradiotherapy (NCRT) in rectal cancer. This study aimed to explore the prognostic impact of lymph node regression grade (LRG) in patients with locally advanced rectal cancer (LARC) following NCRT and radical surgery and develop a predictive nomogram for disease-free survival (DFS). METHODS: LARC patients undergoing NCRT and radical surgery between 2013 and 2014 were enrolled and divided into LRG low (≤ 2), middle (3-9), and high (≥ 10) groups. Clinicopathological characteristics and survival outcomes were compared. Predictors for DFS were identified by Cox regression analysis, and a nomogram was constructed. RESULTS: A total of 257 LARC patients were eligible, including LRG low (n = 149), middle (n = 59), and high (n = 49) groups. Higher LRG score was associated with higher TRG, more advanced ypT and ypN stages, and poorer OS and DFS (all P < 0.001). Cox regression analysis demonstrated that tumor differentiation (poor and anaplastic, HR = 2.048, P = 0.048), ypTNM stage (HR = 2.389, P = 0.015), and LRG-sum (HR = 1.020, P = 0.029) were independent prognostic determinants for DFS after NCRT. A nomogram for DFS was developed with a C-index of 0.68 (95%CI 0.64-0.72). CONCLUSION: LRG is an important prognostic indicator for DFS in LARC patients after NCRT. A predictive nomogram based on LRG was developed to guide more tailored adjuvant treatment and surveillance.

Subtotal colectomy, extended right hemicolectomy, left hemicolectomy, or splenic flexure colectomy for splenic flexure tumors: a network meta-analysis.

AIM: To perform a network meta-analysis of the current literature to evaluate the short-term and long-term outcomes of four operations for splenic flexure tumors. METHODS: An electronic literature search of PubMed, Baidu Scholar, EMBASE, and Cochrane Central Register of Controlled Trials databases was performed up to August 2020. A Bayesian network meta-analysis was utilized to compare the outcomes involved in subtotal colectomy (STC), extended right hemicolectomy (ERHC), standard left hemicolectomy (LHC), and splenic flexure colectomy (SFC) by using R software. RESULTS: A total of 10 non-randomized studies were included in this meta-analysis. There was no statistically significant difference among these 4 surgical techniques in terms of the utilization rate of minimally invasive surgery, reoperative surgery, anastomotic dehiscence, mortality, the proportion of patients with the number of lymph nodes harvested ≥ 12, local recurrence, distant recurrence and overall survival. Although ERHC was associated with a higher risk of postoperative ileus (ERHC vs SFC, OR = 6.4, 95% CI 1.4-45.0, P = 0.019), it has an advantage of a higher rate of primary anastomosis (ERHC vs LHC, OR = 4.2, 95% CI 1.3-18.0, P = 0.019) and a non-significant trend for lower anastomotic dehiscence when compared with more restrict resections. CONCLUSION: SFC, LHC, ERHC and STC for the curative resection of splenic flexure tumors provide similar survival. An individualized surgical plan considering both long-term and short-term outcomes is necessary to select the appropriate operations.

Knockdown of CYP19A1 in Buffalo Follicular Granulosa Cells Results in Increased Progesterone Secretion and Promotes Cell Proliferation.

Cytochrome P450 aromatase 19A1 (CYP19A1) is a critical enzyme in estrogen synthesis. However, the effect of CYP19A1 on cell growth and hormone secretion of buffalo follicular granulosa cells (BFGCs) is poorly understood. The objective of this study was to assess the role of CYP19A1 in cell proliferation and hormone secretion of BFGCs by knocking down CYP19A1 mRNA expression. The mRNA expression level of CYP19A1 gene was knocked down in BFGCs using the siCYP19A1-296 fragment with the best interference efficiency of 72.63%, as affirmed by real-time quantitative PCR (qPCR) and cell morphology analysis. The CYP19A1 knockdown promoted the proliferation of BFGCs through upregulating the mRNA expression levels of six proliferation-related genes (CCND1, CCNE1, CCNB1, CDK2, CDKN1A, and CDKN1B). Moreover, CYP19A1 knockdown increased (P < 0.05) the concentrations of progesterone secretion (P4) in BFGCs through increasing the mRNA expression levels of three steroidogenic genes (HSD17B1, HSD17B7, and CYP17A1). Our data further found that the FSH could inhibit the mRNA expression level of CYP19A1 in BFGCs, while LH obtains the opposite effect. These findings showed that the CYP19A1 knockdown had a regulatory role in the hormone secretion and cell proliferation in BFGCs.