Pharmacological modulation of RB1 activity mitigates resistance to neoadjuvant chemotherapy in locally advanced rectal cancer.

Resistance to neoadjuvant chemotherapy leads to poor prognosis of locally advanced rectal cancer (LARC), representing an unmet clinical need that demands further exploration of therapeutic strategies to improve clinical outcomes. Here, we identified a noncanonical role of RB1 for modulating chromatin activity that contributes to oxaliplatin resistance in colorectal cancer (CRC). We demonstrate that oxaliplatin induces RB1 phosphorylation, which is associated with the resistance to neoadjuvant oxaliplatin-based chemotherapy in LARC. Inhibition of RB1 phosphorylation by CDK4/6 inhibitor results in vulnerability to oxaliplatin in both intrinsic and acquired chemoresistant CRC. Mechanistically, we show that RB1 modulates chromatin activity through the TEAD4/HDAC1 complex to epigenetically suppress the expression of DNA repair genes. Antagonizing RB1 phosphorylation through CDK4/6 inhibition enforces RB1/TEAD4/HDAC1 repressor activity, leading to DNA repair defects, thus sensitizing oxaliplatin treatment in LARC. Our study identifies a RB1 function in regulating chromatin activity through TEAD4/HDAC1. It also provides the combination of CDK4/6 inhibitor with oxaliplatin as a potential synthetic lethality strategy to mitigate oxaliplatin resistance in LARC, whereby phosphorylated RB1/TEAD4 can serve as potential biomarkers to guide the patient stratification.

Nanosensor-based monitoring of autophagy-associated lysosomal acidification in vivo.

Autophagy is a cellular process with important functions that drive neurodegenerative diseases and cancers. Lysosomal hyperacidification is a hallmark of autophagy. Lysosomal pH is currently measured by fluorescent probes in cell culture, but existing methods do not allow for quantitative, transient or in vivo measurements. In the present study, we developed near-infrared optical nanosensors using organic color centers (covalent sp3 defects on carbon nanotubes) to measure autophagy-mediated endolysosomal hyperacidification in live cells and in vivo. The nanosensors localize to the lysosomes, where the emission band shifts in response to local pH, enabling spatial, dynamic and quantitative mapping of subtle changes in lysosomal pH. Using the sensor, we observed cellular and intratumoral hyperacidification on administration of mTORC1 and V-ATPase modulators, revealing that lysosomal acidification mirrors the dynamics of S6K dephosphorylation and LC3B lipidation while diverging from p62 degradation. This sensor enables the transient and in vivo monitoring of the autophagy-lysosomal pathway.

Programming sp3 Quantum Defects along Carbon Nanotubes with Halogenated DNA.

Atomic defect color centers in solid-state systems hold immense potential to advance various quantum technologies. However, the fabrication of high-quality, densely packed defects presents a significant challenge. Herein we introduce a DNA-programmable photochemical approach for creating organic color-center quantum defects on semiconducting single-walled carbon nanotubes (SWCNTs). Key to this precision defect chemistry is the strategic substitution of thymine with halogenated uracil in DNA strands that are orderly wrapped around the nanotube. Photochemical activation of the reactive uracil initiates the formation of sp3 defects along the nanotube as deep exciton traps, with a pronounced photoluminescence shift from the nanotube band gap emission (by 191 meV for (6,5)-SWCNTs). Furthermore, by altering the DNA spacers, we achieve systematic control over the defect placements along the nanotube. This method, bridging advanced molecular chemistry with quantum materials science, marks a crucial step in crafting quantum defects for critical applications in quantum information science, imaging, and sensing.

Morbidity, Mortality, and Pathologic Outcomes of Transanal Versus Laparoscopic Total Mesorectal Excision for Rectal Cancer Short-term Outcomes From a Multicenter Randomized Controlled Trial.

OBJECTIVE: To determine the morbidity, mortality, and pathologic outcomes of transanal total mesorectal resection (taTME) versus laparoscopic total mesorectal excision (laTME) among patients with rectal cancer with clinical stage I to III rectal cancer below the peritoneal reflection. BACKGROUND: Studies with sufficient numbers of patients allowing clinical acceptance of taTME for rectal cancer are lacking. Thus, we launched a randomized clinical trial to compare the safety and efficacy of taTME versus laTME. METHODS: A randomized, open-label, phase 3, noninferiority trial was performed at 16 different hospitals in 10 Chinese provinces. The primary endpoints were 3-year disease-free survival and 5-year overall survival. The morbidity and mortality within 30 days after surgery, and pathologic outcomes were compared based on a modified intention-to-treat principle; this analysis was preplanned. RESULTS: Between April 13, 2016, and June 1, 2021, 1115 patients were randomized 1:1 to receive taTME or laTME. After exclusion of 26 cases, modified intention-to-treat set of taTME versus laTME groups included 544 versus 545 patients. There were no significant differences between taTME and laTME groups in intraoperative complications [26 (4.8%) vs 33 (6.1%); difference, -1.3%; 95% confidence interval (CI), -4.2% to 1.7%; P =0.42], postoperative morbidity [73 (13.4%) vs 66 (12.1%); difference, 1.2%; 95% CI, -2.8% to 5.2%; P =0.53), or mortality [1 (0.2%) vs 1 (0.2%)]. Successful resection occurred in 538 (98.9%) versus 538 (98.7%) patients in taTME versus laTME groups (difference, 0.2%; 95% CI, -1.9% to 2.2%; P >0.99). CONCLUSIONS: Experienced surgeons can safely perform taTME in selected patients with rectal cancer.

An MRI Deep Learning Model Predicts Outcome in Rectal Cancer.

Background Deep learning (DL) models can potentially improve prognostication of rectal cancer but have not been systematically assessed. Purpose To develop and validate an MRI DL model for predicting survival in patients with rectal cancer based on segmented tumor volumes from pretreatment T2-weighted MRI scans. Materials and Methods DL models were trained and validated on retrospectively collected MRI scans of patients with rectal cancer diagnosed between August 2003 and April 2021 at two centers. Patients were excluded from the study if there were concurrent malignant neoplasms, prior anticancer treatment, incomplete course of neoadjuvant therapy, or no radical surgery performed. The Harrell C-index was used to determine the best model, which was applied to internal and external test sets. Patients were stratified into high- and low-risk groups based on a fixed cutoff calculated in the training set. A multimodal model was also assessed, which used DL model-computed risk score and pretreatment carcinoembryonic antigen level as input. Results The training set included 507 patients (median age, 56 years [IQR, 46-64 years]; 355 men). In the validation set (n = 218; median age, 55 years [IQR, 47-63 years]; 144 men), the best algorithm reached a C-index of 0.82 for overall survival. The best model reached hazard ratios of 3.0 (95% CI: 1.0, 9.0) in the high-risk group in the internal test set (n = 112; median age, 60 years [IQR, 52-70 years]; 76 men) and 2.3 (95% CI: 1.0, 5.4) in the external test set (n = 58; median age, 57 years [IQR, 50-67 years]; 38 men). The multimodal model further improved the performance, with a C-index of 0.86 and 0.67 for the validation and external test set, respectively. Conclusion A DL model based on preoperative MRI was able to predict survival of patients with rectal cancer. The model could be used as a preoperative risk stratification tool. Published under a CC BY 4.0 license. Supplemental material is available for this article. See also the editorial by Langs in this issue.

Baseline gut microbiome features prior to SARS-CoV-2 infection are associated with host symptoms in and post COVID-19.

The human gut microbiome varies substantially across individuals and populations and differentially tames our immunity at steady-state. Hence, we hypothesize that the large heterogeneity of gut microbiomes at steady-state may shape our baseline immunity differentially, and then mediate discrepant immune responses and symptoms when one encounters a viral infection, such as SARS-CoV-2 infection. To validate this hypothesis, we conducted an exploratory, longitudinal microbiome-COVID-19 study involving homogenous young participants from two geographically different regions in China. Subjects were recruited and sampled of fecal specimens before the 3-week surge window of COVID-19 (between December 11 and December 31, 2022) in China, and then were followed up for assessment of COVID-19 and post-COVID-19 manifestations. Our data showed that the baseline gut microbiome composition was intricately associated with different COVID-19 manifestations, particularly gastrointestinal involvement and post-COVID-19 lingering symptoms, in both an individual- and population-dependent manner. Our study intriguingly for the first time highlight that the gut microbiome at steady-state may prepare us differentially for weathering a respiratory viral infection.

A Longitudinal MRI-Based Artificial Intelligence System to Predict Pathological Complete Response After Neoadjuvant Therapy in Rectal Cancer: A Multicenter Validation Study.

BACKGROUND: Accurate prediction of response to neoadjuvant chemoradiotherapy is critical for subsequent treatment decisions for patients with locally advanced rectal cancer. OBJECTIVE: To develop and validate a deep learning model based on the comparison of paired MRI before and after neoadjuvant chemoradiotherapy to predict pathological complete response. DESIGN: By capturing the changes from MRI before and after neoadjuvant chemoradiotherapy in 638 patients, we trained a multitask deep learning model for response prediction (DeepRP-RC) that also allowed simultaneous segmentation. Its performance was independently tested in an internal and 3 external validation sets, and its prognostic value was also evaluated. SETTINGS: Multicenter study. PATIENTS: We retrospectively enrolled 1201 patients diagnosed with locally advanced rectal cancer who underwent neoadjuvant chemoradiotherapy before total mesorectal excision. Patients had been treated at 1 of 4 hospitals in China between January 2013 and December 2020. MAIN OUTCOME MEASURES: The main outcome was the accuracy of predicting pathological complete response, measured as the area under receiver operating curve for the training and validation data sets. RESULTS: DeepRP-RC achieved high performance in predicting pathological complete response after neoadjuvant chemoradiotherapy, with area under the curve values of 0.969 (0.942-0.996), 0.946 (0.915-0.977), 0.943 (0.888-0.998), and 0.919 (0.840-0.997) for the internal and 3 external validation sets, respectively. DeepRP-RC performed similarly well in the subgroups defined by receipt of radiotherapy, tumor location, T/N stages before and after neoadjuvant chemoradiotherapy, and age. Compared with experienced radiologists, the model showed substantially higher performance in pathological complete response prediction. The model was also highly accurate in identifying the patients with poor response. Furthermore, the model was significantly associated with disease-free survival independent of clinicopathological variables. LIMITATIONS: This study was limited by its retrospective design and absence of multiethnic data. CONCLUSIONS: DeepRP-RC could be an accurate preoperative tool for pathological complete response prediction in rectal cancer after neoadjuvant chemoradiotherapy. UN SISTEMA DE IA BASADO EN RESONANCIA MAGNTICA LONGITUDINAL PARA PREDECIR LA RESPUESTA PATOLGICA COMPLETA DESPUS DE LA TERAPIA NEOADYUVANTE EN EL CNCER DE RECTO UN ESTUDIO DE VALIDACIN MULTICNTRICO: ANTECEDENTES:La predicción precisa de la respuesta a la quimiorradioterapia neoadyuvante es fundamental para las decisiones de tratamiento posteriores para los pacientes con cáncer de recto localmente avanzado.OBJETIVO:Desarrollar y validar un modelo de aprendizaje profundo basado en la comparación de resonancias magnéticas pareadas antes y después de la quimiorradioterapia neoadyuvante para predecir la respuesta patológica completa.DISEÑO:Al capturar los cambios de las imágenes de resonancia magnética antes y después de la quimiorradioterapia neoadyuvante en 638 pacientes, entrenamos un modelo de aprendizaje profundo multitarea para la predicción de respuesta (DeepRP-RC) que también permitió la segmentación simultánea. Su rendimiento se probó de forma independiente en un conjunto de validación interna y tres externas, y también se evaluó su valor pronóstico.ESCENARIO:Estudio multicéntrico.PACIENTES:Volvimos a incluir retrospectivamente a 1201 pacientes diagnosticados con cáncer de recto localmente avanzado y sometidos a quimiorradioterapia neoadyuvante antes de la escisión total del mesorrecto. Eran de cuatro hospitales en China en el período entre enero de 2013 y diciembre de 2020.PRINCIPALES MEDIDAS DE RESULTADO:Los principales resultados fueron la precisión de la predicción de la respuesta patológica completa, medida como el área bajo la curva operativa del receptor para los conjuntos de datos de entrenamiento y validación.RESULTADOS:DeepRP-RC logró un alto rendimiento en la predicción de la respuesta patológica completa después de la quimiorradioterapia neoadyuvante, con valores de área bajo la curva de 0,969 (0,942-0,996), 0,946 (0,915-0,977), 0,943 (0,888-0,998), y 0,919 (0,840-0,997) para los conjuntos de validación interna y las tres externas, respectivamente. DeepRP-RC se desempeñó de manera similar en los subgrupos definidos por la recepción de radioterapia, la ubicación del tumor, los estadios T/N antes y después de la quimiorradioterapia neoadyuvante y la edad. En comparación con los radiólogos experimentados, el modelo mostró un rendimiento sustancialmente mayor en la predicción de la respuesta patológica completa. El modelo también fue muy preciso en la identificación de los pacientes con mala respuesta. Además, el modelo se asoció significativamente con la supervivencia libre de enfermedad independientemente de las variables clinicopatológicas.LIMITACIONES:Este estudio estuvo limitado por el diseño retrospectivo y la ausencia de datos multiétnicos.CONCLUSIONES:DeepRP-RC podría servir como una herramienta preoperatoria precisa para la predicción de la respuesta patológica completa en el cáncer de recto después de la quimiorradioterapia neoadyuvante. (Traducción-Dr. Felipe Bellolio ).

Intraoperative crystalloid-colloid infusion ratio associated with the development of early surgical complications after ileal pouch-anal anastomosis in ulcerative colitis: a multicenter long-term follow-up study.

BACKGROUND: Intraoperative intravenous fluid administration proves to be associated with surgical patients' postoperative outcomes. Few studies reported the relationship between intraoperative crystalloid-colloid infusion ratio and early surgical complications after ileal pouch-anal anastomosis (IPAA) in ulcerative colitis (UC). METHODS: Data on patients with underwent IPAA from January 2008 to March 2022 at our three inflammatory bowel disease (IBD) surgery centers were retrospectively collected. Intraoperative anesthetic data were recorded and later evaluated by our team anesthesiologist. RESULTS: A total of 140 eligible patients with a median follow-up time of 6.0 years [interquartile range (IQR): 2.0-8.0] were enrolled. Among all enrolled patients, 34 (24.3%) developed early surgical complications after IPAA. Greater blood loss and lower crystalloid-colloid infusion ratio were observed in patients with early surgical complications. Crystalloid-colloid infusion ratio < 2 and blood loss ≥ 200 ml had the most significant area under the receiver-operating characteristic curve (AUC) of 0.664 and 0.674 in predicting early surgical complications. Crystalloid-colloid infusion ratio < 2 [odds ratio (OR), 2.571; 95% confidence intervals (CI), 1.067-6.195, p = 0.035] and blood loss ≥ 200 ml (OR, 3.165; 95% CI, 1.288-7.777, p = 0.012) were independent risk factors for the development of early post-IPAA complications. CONCLUSION: Intraoperative crystalloid-colloid infusion ratio < 2 and blood loss volume over 200 ml during IPAA contribute to the occurrence of early surgical complications. Early attentions and necessary interventions are warranted to avoid these risk factors during the IPAA surgery in order to prevent the development of early surgical complications.

Adaptation and validation of the Evidence-based Practice Profile Questionnaire (EBP2Q) for clinical postgraduates in a Chinese context.

BACKGROUND: Evidence-based practice (EBP) is an essential approach of optimizing patient outcomes and driving progress in clinical practice. As an important reserve talent of medical staff and researchers, the clinical postgraduates are expected to become the backbones of supporting the implementation of EBP in clinical units after graduation. The assessment of their EBP learning outcomes is an important issue, yet few tools have been developed specifically in Mainland China. The purpose of this study is to adapt the Evidence-Based Practice Profile Questionnaire (EBP2Q) to Mainland China's cultural context and to evaluate the psychometric properties of the Chinese EBP2Q in clinical postgraduates. METHODS: Cross-cultural modification, including translating the original EBP2Q into Chinese was implemented according to established guidelines. A pilot study was carried out in Mainland China among 30 clinical postgraduates. A subsequent validation study was conducted among 633 clinical postgraduates majoring in clinical medicine, stomatology and nursing from Mainland China. Construct validity was assessed by exploratory factor analysis (n = 313), together with confirmatory factor analysis (n = 320). Reliability was determined by internal consistency and test-retest reliability. RESULTS: The Chinese EBP2Q consisted of 40 items. The content validity index of the Chinese EBP2Q achieved 0.938 at an acceptable level. Principal component analysis resulted in a four-factor structure explaining 61.586% of the total variance. All fitting indices satisfied the standard based upon confirmatory factor analyses, indicating that the four-factor structure contributed to an ideal model fit. The internal consistency appeared high for the Chinese EBP2Q, reaching a Cronbach's alpha value of 0.926. Test-retest reliability was 0.868 and the split-half coefficient was 0.925. CONCLUSION: Chinese version of EBP2Q possesses adequate validity, test-retest reliability and internal consistency. It is a promising questionnaire to be adopted by Chinese medical educators in designing their course and curriculum, or by clinical postgraduates for self-assessment of EBP learning.

Quantum Defects: What Pairs with the Aryl Group When Bonding to the sp2 Carbon Lattice of Single-Wall Carbon Nanotubes?

Aryl diazonium reactions are widely used to covalently modify graphitic electrodes and low-dimensional carbon materials, including the recent creation of organic color centers (OCCs) on single-wall carbon nanotube semiconductors. However, due to the experimental difficulties in resolving small functional groups over extensive carbon lattices, a basic question until now remains unanswered: what group, if any, is pairing with the aryl sp3 defect when breaking a C═C bond on the sp2 carbon lattice? Here, we show that water plays an unexpected role in completing the diazonium reaction with carbon nanotubes involving chlorosulfonic acid, acting as a nucleophilic agent that contributes -OH as the pairing group. By simply replacing water with other nucleophilic solvents, we find it is possible to create OCCs that feature an entirely new series of pairing groups, including -OCH3, -OC2H5, -OC3H7, -i-OC3H7, and -NH2, which allows us to systematically tailor the defect pairs and the optical properties of the resulting color centers. Enabled by these pairing groups, we further achieved the synthesis of OCCs with sterically bulky pairs that exhibit high purity defect photoluminescence effectively covering both the second near-infrared window and the telecom wavelengths. Our studies further suggest that these diazonium reactions proceed through the formation of carbocations in chlorosulfonic acid, rather than a radical mechanism that typically occurs in aqueous solutions. These findings uncover the unknown half of the sp3 defect pairs and provide a synthetic approach to control these defect color centers for quantum information, imaging, and sensing.

Marimastat alleviates oxidative stress induced cellular senescence by activating autophagy.

Marimastat is one of the potent inhibitors of MMP (MMPIs) with few side effects. The impact of marimastat on cellular senescence remains unexplored. Our study evaluated the marimastate effect on oxidative stress-induced cell senescence using NIH3T3 cells. Marimastate administration was found to suppress senescence-ß-galactosidase (SA-ß-gal) activity and development linked with aging. Furthermore, we observed that this effect of marimastat was closely linked with the recovery of autophagy dysfunction and mTOR suppression in H2O2-treated cells. Notably, this study demonstrated the marimastat effect on senescence inhibition for the first time.

CT-based radiogenomic analysis dissects intratumor heterogeneity and predicts prognosis of colorectal cancer: a multi-institutional retrospective study.

BACKGROUND: This study aimed to develop a radiogenomic prognostic prediction model for colorectal cancer (CRC) by investigating the biological and clinical relevance of intratumoural heterogeneity. METHODS: This retrospective multi-cohort study was conducted in three steps. First, we identified genomic subclones using unsupervised deconvolution analysis. Second, we established radiogenomic signatures to link radiomic features with prognostic subclone compositions in an independent radiogenomic dataset containing matched imaging and gene expression data. Finally, the prognostic value of the identified radiogenomic signatures was validated using two testing datasets containing imaging and survival information collected from separate medical centres. RESULTS: This multi-institutional retrospective study included 1601 patients (714 females and 887 males; mean age, 65 years ± 14 [standard deviation]) with CRC from 5 datasets. Molecular heterogeneity was identified using unsupervised deconvolution analysis of gene expression data. The relative prevalence of the two subclones associated with cell cycle and extracellular matrix pathways identified patients with significantly different survival outcomes. A radiogenomic signature-based predictive model significantly stratified patients into high- and low-risk groups with disparate disease-free survival (HR = 1.74, P = 0.003). Radiogenomic signatures were revealed as an independent predictive factor for CRC by multivariable analysis (HR = 1.59, 95% CI:1.03-2.45, P = 0.034). Functional analysis demonstrated that the 11 radiogenomic signatures were predominantly associated with extracellular matrix and immune-related pathways. CONCLUSIONS: The identified radiogenomic signatures might be a surrogate for genomic signatures and could complement the current prognostic strategies.

The growth pattern of liver metastases on MRI predicts early recurrence in patients with colorectal cancer: a multicenter study.

OBJECTIVES: The multicenter study aimed to explore the relationship between the growth pattern of liver metastases on preoperative MRI and early recurrence in patients with colorectal cancer liver metastases (CRCLM) after surgery. METHODS: A total of 348 CRCLM patients from 3 independent centers were enrolled, including 130 patients with 339 liver metastases in the primary cohort and 218 patients in validation cohorts. Referring to the gross classification of hepatocellular carcinoma (HCC), the growth pattern of each liver metastasis on MRI was classified into four types: rough, smooth, focal extranodular protuberant (FEP), and nodular confluent (NC). Disease-free survival (DFS) curve was constructed using the Kaplan-Meier method. RESULTS: In primary cohort, 42 (12.4%) of the 339 liver metastases were rough type, 237 (69.9%) were smooth type, 29 (8.6%) were FEP type, and 31 (9.1%) were NC type. Those patients with FEP- and/or NC-type liver metastases had shorter DFS than those without such metastases (p < 0.05). However, there were no significant differences in DFS between patients with rough- and smooth-type liver metastases and those without such metastases. The patients with FEP- and/or NC-type liver metastases also had shorter DFS than those without such metastases in two external validation cohorts. In addition, 40.5% of high-risk-type (FEP and NC) liver metastases converted to low-risk types (rough and smooth) after neoadjuvant chemotherapy. CONCLUSION: The FEP- and NC-type liver metastases were associated with early recurrence, which may facilitate the clinical treatment of CRCLM patients. KEY POINTS: • In the primary cohort, patients with FEP- and NC-type metastases had shorter disease-free survival (DFS) and a higher intrahepatic recurrence rate than patients without such metastases in the liver. • In the primary cohort, there were no significant differences in DFS or intrahepatic recurrence rate between patients with rough- and smooth-type metastases and those without such metastases in the liver. • High-risk patients had shorter DFS and a higher intrahepatic recurrence rate than low-risk patients in primary and external validation cohorts.

Denosumab Versus Bisphosphonates for the Prevention of the Vertebral Fractures in Men with Osteoporosis: An Updated Network Meta-Analysis.

BACKGROUND: The efficacy of the prevention of vertebral fractures in men with osteoporosis by treatment with denosumab is debated. This study aimed to update the comparative effectiveness of denosumab and bisphosphonates for preventing vertebral fractures in men with osteoporosis. METHODS: We searched PubMed, EMBASE, and Cochrane Central Register of Controlled Trials for randomized controlled trials that enrolled men with osteoporosis. Fixed-effects network meta-analysis was performed to evaluate the risk of vertebral fractures, and the relative risk (RR) and 95% confident interval (CI) values were calculated. RESULTS: Sixteen studies were included, and the identified bisphosphonates were risedronate, alendronate, zoledronic acid, and ibandronate. Compared with placebo or control, a significant reduction in vertebral fractures was observed for denosumab (RR 0.30, 95%CI 0.13 0.68), risedronate (RR 0.39, 95%CI 0.19 0.77), and zoledronic acid (RR 0.45, 95%CI 0.21 0.98). According to the surface under the cumulative ranking curve (SUCRA), denosumab was the most effective one among the included agents for the risk reduction of vertebral fracture. However, compared with each bisphosphonate, the RR values of denosumab were not significant [RR 0.78 (95%CI 0.25 2.43) vs. risedronate, RR 0.55 (95%CI 0.18 1.75) vs. alendronate, RR 0.66 (95%CI 0.19 2.32) vs. zoledronic acid and RR 1.12 (95%CI 0.08 14.83) vs. ibandronate]. CONCLUSION: Denosumab effectively reduced the risk of vertebral fractures in men with osteoporosis, and this effect was comparable to that of bisphosphonates.

Cancer-associated fibroblasts impact the clinical outcome and treatment response in colorectal cancer via immune system modulation: a comprehensive genome-wide analysis.

BACKGROUND: Cancer-associated fibroblasts (CAFs) in the tumour microenvironment are associated with poor prognosis and chemoresistance in multiple solid tumours. However, there is a lack of universal measures of CAFs in colorectal cancer (CRC). The aim of this study was to assess the utility of a fibroblast-related gene signature (FRGS) for predicting patient outcomes and reveal its relevant mechanism. METHODS: The GSE39582 dataset, which includes 316 CRC patients who did not receive adjuvant chemotherapy was used as a discovery cohort to identify the prognostic fibroblast-related genes (FRGs). A total of 1352 CRC patients were divided into one training cohort (GSE39582, n = 461) and two validation cohorts (TCGA, n = 338; meta-validation, n = 553) for the construction of the FRGS and the verification of its prognostic value in stage II/III CRC patients. Functional annotation and analysis were performed to explore the underlying mechanism. The ability of the FRGS to predict immunotherapy response was further tested in a clear cell renal cell carcinoma (ccRCC) cohort. RESULTS: An 11-gene signature that had prognostic value for stage II/III CRC patients in both validation cohorts was developed (TCGA cohort: HR = 1.90, 95% CI 1.16-3.12, P < 0.01; meta-validation cohort: HR = 1.95, 95% CI 1.39-2.73, P < 0.001). A high level of CAFs was correlated with worse prognosis in CRC patients who did not receive adjuvant chemotherapy (HR = 3.63, 95% CI 2.24-5.88, P < 0.001). Importantly, patients in the low-risk group were found to be benefit from chemotherapy (P < 0.01), but not in the high CAF group (P > 0.05). Similar results were found in the TCGA cohort. Integrated with clinical characteristics, the FRGS was confirmed to be an independent prognostic factor in the multivariate analysis after adjustment for tumour TNM stage (GSE39582 cohort: HR = 3.19, 95% CI 1.88-5.41, P < 0.001; TCGA cohort: HR = 5.00, 95% CI 1.58-15.85, P = 0.007; meta-validation cohort: HR = 2.99, 95% CI 1.44-6.21, P = 0.003). Furthermore, the enrichment analysis found that the antitumour immune response was suppressed and the infiltration of CD4 T cells and M1 macrophages was depressed in the high CAF group. The FRGS was also found to have value in predicting for immunotherapy response in the ccRCC cohort. CONCLUSIONS: The 11-gene FRGS had independent prognostic value for CRC patients, as well as utility in the prediction of benefit from chemotherapy. CAFs in the tumour microenvironment might have an impact on the prognosis of CRC patients via inhibiting immune response.

Modified FOLFOXIRI With or Without Cetuximab as Conversion Therapy in Patients with RAS/BRAF Wild-Type Unresectable Liver Metastases Colorectal Cancer: The FOCULM Multicenter Phase II Trial.

PURPOSE: This trial evaluated the addition of cetuximab to a modified FOLFOXIRI (mFOLFOXIRI: 5-fluorouracil/folinic acid, oxaliplatin, irinotecan) as conversion therapy in a two-group, nonrandomized, multicenter, phase II trial in patients with initially technically unresectable colorectal liver-limited metastases (CLM) and BRAF/RAS wild-type. PATIENTS AND METHODS: Patients were enrolled to receive cetuximab (500 mg/m2 ) plus mFOLFOXIRI (oxaliplatin 85 mg/m2 , irinotecan 165 mg/m2 , folinic acid 400 mg/m2 , 5-fluorouracil 2,800 mg/m2 46-hour infusion, every 2 weeks) (the cetuximab group) or the same regimen of mFOLFOXIRI alone (the control group), in a 2:1 ratio allocation. The primary endpoint was the rate of no evidence of disease (NED) achieved. Secondary endpoints included resection rate, objective response rate (ORR), survival, and safety. RESULTS: Between February 2014 and July 2019, 117 patients were registered for screening at six centers in China, and 101 of these were enrolled (67 cetuximab group, 34 control group). The rate of NED achieved was 70.1% in the cetuximab group and 41.2% in the control group (difference 29.0%; 95% confidence interval [CI], 9.1%-48.8%; p = .005). Patients in the cetuximab group had improved ORR (95.5% vs. 76.5%; difference 19.1%; 95% CI, 17.4%-36.4%; p = .010) compared with those in control group. Progression-free survival and overall survival showed the trend to favor the cetuximab group. The incidence of grade 3 and 4 adverse events was similar in the two groups. CONCLUSION: Addition of cetuximab to mFOLFOXIRI improved the rate of NED achieved. This combination could be an option of conversion regimen for molecularly selected patients with initially technically unresectable CLM. IMPLICATIONS FOR PRACTICE: This trial evaluated the addition of cetuximab to a modified FOLFOXIRI as conversion therapy in a phase II trial in patients with initially technically unresectable colorectal liver-limited metastases and BRAF/RAS wild-type. The rate of no evidence of disease achieved was 70.1% in the cetuximab plus modified FOLFOXIRI group and 41.2% in the modified FOLFOXIRI group. Objective response rates, overall survival, and progression-free survival were improved in the cetuximab group when compared with the modified FOLFOXIRI group. Addition of cetuximab to modified FOLFOXIRI increased the rate of no evidence of disease achieved, and this combination could be an option of conversion regimen for molecularly selected patients with initially technically unresectable colorectal liver-limited metastasis.

Protein-protein interaction analysis reveals a novel cancer stem cell related target TMEM17 in colorectal cancer.

BACKGROUND: Cancer stem cells (CSCs) are a small subpopulation of cells within tumors with stem cell property. Increased evidence suggest that CSCs could be responsible for chemoresistance and recurrence in colorectal cancer (CRC). However, a reliable therapeutic target on CSCs is still lacking. METHODS: Here we describe a two-step strategy to generate CSC targets with high selectivity for colon stem cell markers, specific proteins that are interacted with CSC markers were selected and subsequently validated in a survival analysis. TMEM17 protein was found and its biological functions in CRC cells were further examined. Finally, we utilized the Gene Set Enrichment Analysis (GSEA) to investigate the potential mechanisms of TMEM17 in CRC. RESULTS: By combining protein-protein interaction (PPI) database and high-throughput gene profiles, network analysis revealed a cluster of colon CSCs related genes. In the cluster, TMEM17 was identified as a novel CSCs related gene. The results of in-vitro functional study demonstrated that TMEM17 depletion can suppress the proliferation of CRC cells and sensitize CRC cells to chemotherapy drugs. Enrichment analysis revealed that the expression of TMEM17 is associated with the magnitude of activation of the Wnt/ß-catenin pathway. Further validation in clinical samples demonstrated that the TMEM17 expression was much higher in tumor than normal tissue and was associated with poor survival in CRC patients. CONCLUSION: Collectively, our finding unveils the critical role of TMEM17 in CRC and TMEM17 could be a potential effective therapeutic target for tumor recurrence and chemoresistance in the colorectal cancer (CRC).

Impact of pelvic dimensions on anastomotic leak after anterior resection for patients with rectal cancer.

AIM: The impact of pelvis on the development of anastomotic leak (AL) in rectal cancer (RC) patients who underwent anterior resection (AR) remains unclear. The aim of this study was to evaluate the impact of pelvic dimensions on the risk of AL. METHODS: A total of 1058 RC patients undergoing AR from January 2013 to January 2016 were enrolled. Pelvimetric parameters were obtained using abdominopelvic computed tomography scans. RESULTS: Univariate analyses showed that pelvic inlet, pelvic outlet, interspinous distance, and intertuberous distance were significantly associated with the risk for AL (P < 0.05). Multivariate analysis confirmed that pelvic inlet and intertuberous distance were independent risk factors for AL (P < 0.05). Significant factors from multivariate analysis were assembled into the nomogram A (without pelvic dimensions) and nomogram B (with pelvic dimensions). The area under curve (AUC) of nomogram B was 0.72 (95% CI 0.67-0.77), which was better than the AUC of nomogram A (0.69, [95% CI 0.65-0.74]), but didn't reach a statistical significance (P = 0.199). Decision curve supported that nomogram B was better than nomogram A. CONCLUSION: Pelvic dimensions, specifically pelvic inlet and intertuberous distance, seemed to be independent predictors for postoperative AL in RC patients. Pelvic inlet and intertuberous distance incorporated with preoperative radiotherapy, preoperative albumin, conversion, and tumor diameter in the nomogram might provide a clinical tool for predicting AL.

circCAMSAP1 Promotes Tumor Growth in Colorectal Cancer via the miR-328-5p/E2F1 Axis.

Increasing studies indicated that circular RNAs (circRNAs) play important roles in cancer progression. However, the roles of circRNAs in colorectal cancer (CRC) remain largely unknown. In this study, we determined the circRNA expression profile by next-generation RNA sequencing from eight CRC and paired non-cancerous matched tissues. circCAMSAP1 (originating from exon 2 to exon 3 of the CAMSAP1 gene, hsa_circ_0001900) was significantly upregulated in CRC tissues. Increased circCAMSAP1 expression was significantly correlated with advanced tumor/node/metastasis (TNM) stage and shortened overall survival. An elevation of circCAMSAP1 expression was detected via droplet digital PCR in the serum of CRC patients prior to surgery. Functionally, circCAMSAP1 promoted the malignant behavior of CRC. Mechanism study of upstream biogenesis of circCAMSAP1 indicated that circCAMSAP1 cyclization in CRC was mediated by splicing factor epithelial-splicing regulatory protein 1. Moreover, circCAMSAP1 acted as a sponge for miR-328-5p and abrogated its suppression on transcription factor E2F1. Taken together, our data indicated an essential role of the circCAMSAP1/miR-328-5p/E2F1 axis in the progression of CRC, which implied that circCAMSAP1 could serve as a diagnostic and prognostic biomarker as well as a potential therapeutic target for CRC.

Hypoxic tumor microenvironment activates GLI2 via HIF-1α and TGF-ß2 to promote chemoresistance in colorectal cancer.

Colorectal cancer patients often relapse after chemotherapy, owing to the survival of stem or progenitor cells referred to as cancer stem cells (CSCs). Although tumor stromal factors are known to contribute to chemoresistance, it remains not fully understood how CSCs in the hypoxic tumor microenvironment escape the chemotherapy. Here, we report that hypoxia-inducible factor (HIF-1α) and cancer-associated fibroblasts (CAFs)-secreted TGF-ß2 converge to activate the expression of hedgehog transcription factor GLI2 in CSCs, resulting in increased stemness/dedifferentiation and intrinsic resistance to chemotherapy. Genetic or small-molecule inhibitor-based ablation of HIF-1α/TGF-ß2-mediated GLI2 signaling effectively reversed the chemoresistance caused by the tumor microenvironment. Importantly, high expression levels of HIF-1α/TGF-ß2/GLI2 correlated robustly with the patient relapse following chemotherapy, highlighting a potential biomarker and therapeutic target for chemoresistance in colorectal cancer. Our study thus uncovers a molecular mechanism by which hypoxic colorectal tumor microenvironment promotes cancer cell stemness and resistance to chemotherapy and suggests a potentially targeted treatment approach to mitigating chemoresistance.