SRSF3 shapes the structure of miR-17-92 cluster RNA and promotes selective processing of miR-17 and miR-20a.

MicroRNA (miRNA) biogenesis is tightly regulated to maintain distinct miRNA expression patterns. Almost half of mammalian miRNAs are generated from miRNA clusters, but this process is not well understood. We show here that Serine-arginine rich splicing factor 3 (SRSF3) controls the processing of miR-17-92 cluster miRNAs in pluripotent and cancer cells. SRSF3 binding to multiple CNNC motifs downstream of Drosha cleavage sites within miR-17-92 is required for the efficient processing of the cluster. SRSF3 depletion specifically compromises the processing of two paralog miRNAs, miR-17 and miR-20a. In addition to SRSF3 binding to the CNNC sites, the SRSF3 RS-domain is essential for miR-17-92 processing. SHAPE-MaP probing demonstrates that SRSF3 binding disrupts local and distant base pairing, resulting in global changes in miR-17-92 RNA structure. Our data suggest a model where SRSF3 binding, and potentially its RS-domain interactions, may facilitate an RNA structure that promotes miR-17-92 processing. SRSF3-mediated increase in miR-17/20a levels inhibits the cell cycle inhibitor p21, promoting self-renewal in normal and cancer cells. The SRSF3-miR-17-92-p21 pathway operates in colorectal cancer, linking SRSF3-mediated pri-miRNA processing and cancer pathogenesis.

Comparison of quality of life, symptom and functional outcomes following surgical treatment for colorectal neoplasia.

BACKGROUND: Colorectal surgical procedures can have a significant impact on quality-of-life (QoL), functional and symptom outcomes. This retrospective study conducted in a tertiary care center evaluated the influence of four colorectal surgical procedures on patient-reported outcome measures (PROMs). METHODS: 512 patients undergoing colorectal neoplasia surgery between June 2015 and December 2017 were identified via the Cabrini Monash Colorectal Neoplasia database. Primary outcomes measured were the mean changes in PROMs following surgery utilizing the International Consortium of Health Outcome Measures colorectal cancer (CRC) PROMs. RESULTS: 242 patients from 483 eligible patients responded (50% participation rate). Responders and non-responders were comparable in median age (72 vs. 70 years), gender (48% vs. 52% male), time from surgery (<1 and >1 year), overall stage at diagnosis and type of surgery. Respondents underwent either a right hemicolectomy, ultra-low anterior resection, abdominoperineal resection or a transanal endoscopic microsurgery/transanal minimally invasive surgery. Right hemicolectomy patients reported the best post-operative function and reduced symptoms, significantly better (P < 0.01) than ultra-low anterior resection patients who reported the worst outcomes in multiple areas (body image, embarrassment, flatulence, diarrhoea, stool frequency). Furthermore, patients undergoing an abdominoperineal resection reported the worst scores for body image, urinary frequency, urinary incontinence, buttock pain, faecal incontinence and male impotence. CONCLUSIONS: The differences in PROMs in CRC surgical procedures is demonstrable. The worst post-operative functional and symptom scores were reported after either an ultra-low anterior resection or an abdominoperineal resection. Implementation of PROMs will identify and aid early patient referral to allied health and support services.

Factors affecting the post-operative outcomes in patients aged over 80 following colorectal cancer surgery.

PURPOSE: In 2019, in Australia, there were 500,000 people aged 85 and over. Traditionally, clinicians have adopted the view that surgery is not desirable in this cohort due to increasing perioperative risk, perceived minimal clinical benefit, and shortened life expectancy. This cohort study is aimed at investigating postoperative outcomes from elective and non-elective colorectal cancer surgery in patients aged 80 and over. METHODS: A retrospective analysis was conducted on patients from 2010 to 2020 on a prospectively maintained colorectal database. Patients aged over 80 who underwent surgical resection for colorectal cancer were reviewed. Oncological characteristics, short-term outcomes, overall survival, and relapse-free survival rates were analysed. RESULTS: A total of 832 patients were identified from the database. Females comprised 55% of patients aged 80 and above. The median age was 84 for octogenarians and 92 for nonagenarians. Most patients were ASA 2 (212) or ASA 3 (501). ASA 3 and 4 and stage III pathology were associated with higher postoperative complications. Fifty percent of over 80 s and 37% of over 90 s were surgically discharged to their own home. Overall survival at 30, 180, and 360 days and 5 years was 98.1%, 93.1%, 87.2%, and 57.2% for the over 80 s and 98.1%, 88.9%, 74.9%, and 24.4% for the over 90 s. CONCLUSION: Our results demonstrate that surgical treatment of older patients is safe with acceptable short-, medium-, and long-term survival. Nonetheless, efforts are needed to reduce the rates of complications in older patients, including utilisation of multi-disciplinary teams to assess the optimal treatment strategy and postoperative care.

The effect of anti-spasmodic administration on the accuracy of magnetic resonance imaging staging of rectal cancer.

BACKGROUNDS: Magnetic resonance imaging is the primary method for local staging in rectal cancer patients. Administration of intravenous (IV) hyoscine butylbromide is thought to improve accuracy, but there are contraindications and potential adverse effects. The aim was to assess the efficacy of IV hyoscine butylbromide on the accuracy of MRI rectal cancer staging of T2 and T3 rectal cancers. METHODS: A retrospective cohort study was carried out on patients prospectively recorded on the Cabrini Monash colorectal neoplasia database. A total of 74 patients (53 males, 21 females) MRI pelvis and rectums with antispasmodics were performed at multiple centres in the pre-operative setting between 2010 and 2016. Each patient underwent total mesorectal excision of rectal cancer. The excision specimens were assessed and given a pathological TNM stage, which was considered the reference standard. RESULTS: There was no statistically significant impact on the overall accuracy of MRI rectal cancer staging between patient groups who received IV hyoscine butylbromide and groups who did not receive IV hyoscine butylbromide. The accuracy of T2 and T3 staged rectal cancers was more likely to be correct (compared with T1 cancers) with the administration of IV hyoscine butylbromide. Still, there was no improvement in the accuracy of N-staging. CONCLUSION: Given the potential side effects and adverse outcomes of IV anti-spasmodic agents, department protocols may need to be re-assessed regarding the prescription of these medications for MRI rectal cancer staging.

Impact of Anastomotic Leak on Long-term Oncological Outcomes After Restorative Surgery for Rectal Cancer: A Retrospective Cohort Study.

BACKGROUND: Anastomotic leak after restorative surgery for rectal cancer is a major complication and may lead to worse long-term oncological and survival outcomes. OBJECTIVE: The purpose of this study was to identify risk factors associated with anastomotic leak and to assess the perioperative and long-term oncological impact of anastomotic leak in our cohort of patients with rectal cancer. DESIGN: A retrospective analysis was performed on data from the prospectively maintained Cabrini Monash colorectal neoplasia database. Patients who had undergone rectal cancer resection and subsequently received anastomosis between November 2009 and May 2020 were included in this study. Patient and tumor characteristics, technical risk factors, and short-term and perioperative as well as long-term oncological and survival outcomes were assessed. SETTINGS: The study was conducted in 3 tertiary hospitals. PATIENTS: A total of 693 patients met the inclusion criteria for this study. MAIN OUTCOME MEASURES: Univariate analyses were performed to assess the relationship between anastomotic leak and patient and technical risk factors, as well as perioperative and long-term outcomes. Univariate and multivariate proportional HR models of overall and disease-free survival were calculated. Kaplan-Meier survival analyses assessed disease-free and overall survival. RESULTS: Anastomotic leak rate was 3.75%. Males had an increased risk of anastomotic leak, as did patients with hypertension and ischemic heart disease. Patients who experience an anastomotic leak were more likely to require reoperation and hospital readmission and were more likely to experience an inpatient death. Disease-free and overall survival were also negatively impacted by anastomotic leaks. LIMITATIONS: This is a retrospective analysis of data from only 3 centers with the usual limitations. However, these effects have been minimized because of the high quality and completeness of the prospective data collection. CONCLUSIONS: Anastomotic leaks after restorative surgery negatively affect long-term oncological and survival outcomes for patients with rectal cancer. See Video Abstract at http://links.lww.com/DCR/C81 . IMPACTO DE LA FUGA ANASTOMTICA EN LOS RESULTADOS ONCOLGICOS A LARGO PLAZO TRAS CIRUGA RESTAURADORA PARA EL CNCER DE RECTO UN ESTUDIO DE COHORTE RETROSPECTIVO: ANTECEDENTES:La fuga anastomótica tras una cirugía restauradora para el cáncer de recto es una complicación mayor y puede conducir a peores resultados oncológicos y de supervivencia a largo plazo.OBJETIVO:El propósito de este estudio fue identificar los factores de riesgo asociados con la fuga anastomótica y evaluar el impacto oncológico perioperatorio y a largo plazo de la fuga anastomótica en nuestra cohorte de pacientes con cáncer de recto.DISEÑO:Se realizó un análisis retrospectivo de datos obtenidos de la base de datos Cabrini Monash sobre neoplasia colorrectal la cual es mantenida prospectivamente. Se incluyeron en este estudio pacientes que fueron sometidos a una resección del cáncer de recto y que posteriormente recibieron una anastomosis entre noviembre de 2009 y mayo de 2020. Se evaluaron las características del paciente y del tumor, los factores de riesgo relacionados a la técnica, los resultados oncológicos y de supervivencia perioperatorio, así como los resultados a corto y largo plazo.AJUSTES:El estudio se realizó en tres hospitales terciarios.PACIENTES:Un total de 693 pacientes cumplieron con los criterios de inclusión para este estudio.PRINCIPALES MEDIDAS DE RESULTADO:Se realizaron análisis univariados para evaluar la relación entre la fuga anastomótica y aquellos factores relacionados al paciente, a la técnica, así como los resultados perioperatorios y a largo plazo. Se calcularon modelos de razón de riesgo proporcional univariante y multivariante de supervivencia global y libre de enfermedad. Los análisis de supervivencia de Kaplan-Meier evaluaron la supervivencia libre de enfermedad y la supervivencia global.RESULTADOS:La tasa de fuga anastomótica fue del 3,75%. Los hombres tenían un mayor riesgo de fuga anastomótica al igual que aquellos pacientes con hipertensión y cardiopatía isquémica. Los pacientes que sufrieron una fuga anastomótica tuvieron mayores probabilidades de requerir una reintervención y reingreso hospitalario, así como también tuvieron mayores probabilidades de sufrir una muerte hospitalaria. La supervivencia libre de enfermedad y general también se vio afectada negativamente por las fugas anastomóticas.LIMITACIONES:Este es un análisis retrospectivo de datos de solo tres centros con las limitaciones habituales. Sin embargo, estos efectos han sido minimizados debido a la alta calidad y la exhaustividad de la recopilación prospectiva de datos.CONCLUSIONES:Las fugas anastomóticas después de una cirugía restauradora afectan negativamente los resultados oncológicos y de supervivencia a largo plazo para los pacientes con cáncer de recto. Consulte Video Resumen en http://links.lww.com/DCR/C81 . (Traducción-Dr. Osvaldo Gauto ).

Preferential Antibody and Drug Conjugate Targeting of the ADAM10 Metalloprotease in Tumours.

ADAM10 is a transmembrane metalloprotease that sheds a variety of cell surface proteins, including receptors and ligands that regulate a range of developmental processes which re-emerge during tumour development. While ADAM10 is ubiquitously expressed, its activity is normally tightly regulated, but becomes deregulated in tumours. We previously reported the generation of a monoclonal antibody, 8C7, which preferentially recognises an active form of ADAM10 in human and mouse tumours. We now report our investigation of the mechanism of this specificity, and the preferential targeting of 8C7 to human tumour cell xenografts in mice. We also report the development of novel 8C7 antibody-drug conjugates that preferentially kill cells displaying the 8C7 epitope, and that can inhibit tumour growth in mice. This study provides the first demonstration that antibody-drug conjugates targeting an active conformer of ADAM10, a widely expressed transmembrane metalloprotease, enable tumour-selective targeting and inhibition.

A comparison of extracorporeal side to side or end to side anastomosis following a laparoscopic right hemicolectomy for colon cancer.

BACKGROUND: This study aimed to investigate whether an extracorporeal side-to-side (SS) or end-to-side (ES) stapled anastomosis impacts short-term and long-term outcomes after an oncological laparoscopic right hemicolectomy. METHODS: A retrospective cohort study of prospectively collected data from two Victorian tertiary referral hospitals was performed. Patients who underwent oncological resection for colorectal cancer between February 2010 and September 2020 were selected from the colorectal neoplasia database. Patients were divided into two groups depending on the type of stapled anastomosis: Group 1 (functional end-to-end/side-to-side (SS)); and Group 2 (end-to-side (ES)). Primary outcomes were anastomotic leak, postoperative ileus, mortality and morbidity, length of stay post-surgery, readmission to hospital, and 30-day mortality. RESULTS: This large case series of 1040 patients (SS = 625, ES = 415) demonstrated that the type of stapling technique impacted operative duration and postoperative ileus rates. Patients in the SS group had a faster operation of 108 min rather than 130 min in the ES group (p < 0.001). The SS group were more likely to experience a post-operative ileus (p < 0.001) with no impact on length of stay (SS, 7 days versus ES, 7 days; p = 0.14). There were no differences between the two groups with respect to lymph node yield, lymph node ratio, anastomotic leaks, return to theatre, 30-day mortality and 5-year overall survival. DISCUSSION: The type of extracorporeal stapled anastomosis following an oncological laparoscopic right hemicolectomy has minimal impact on morbidity and survival outcomes; however, a side-to-side stapled anastomosis is more likely to be a faster operation with a higher postoperative ileus rate.

Surgical Techniques for Abdominoperineal Resection for Rectal Cancer: One Size Does Not Fit All.

Abdominoperineal resection (APR) of rectal cancer is associated with poorer oncological outcomes than anterior resection. This may be due to higher rates of intra-operative perforation (IOP) and circumferential resection margin (CRM) involvement causing higher recurrence rates and surgical complications. To address these concerns, several centers advocated a change in technique from a standard APR to a more radical extra-levator abdominoperineal excision (ELAPE). Initial reports showed that ELAPE reduced IOP rates and CRM involvement but increased wound complications and longer surgical duration. However, many of these studies had unacceptable rates of IOP and CRM before retraining in ELAPE. This may indicate that it was a sub-optimal surgical technique, which improved upon training, that had influenced the high CRM and IOP rates rather than the technique itself. Subsequent studies demonstrated that the CRM involvement rate for ELAPE was not always lower than for standard APR and, in some cases, significantly higher. The morbidity of ELAPE can be high, with studies reporting higher adverse events than APR, especially in terms of wound complications from the larger perineal incision required in ELAPE. Whether ELAPE improves short- or long-term oncological outcomes for patients has not been clearly demonstrated. The authors propose that all centers performing rectal cancer surgery audit surgical outcomes of patients undergoing APR or ELAPE and examine CRM involvement, IOP rates, and local recurrence rates, preferably through a national body. If rates of adverse technical or oncological outcomes exceed acceptable levels, then retraining in the appropriate surgical techniques may be indicated.

Modeling colorectal cancer: A bio-resource of 50 patient-derived organoid lines.

BACKGROUND AND AIM: Colorectal cancer (CRC) is the second leading cause of cancer death worldwide. To improve outcomes for these patients, we need to develop new treatment strategies. Personalized cancer medicine, where patients are treated based on the characteristics of their own tumor, has gained significant interest for its promise to improve outcomes and reduce unnecessary side effects. The purpose of this study was to examine the potential utility of patient-derived colorectal cancer organoids (PDCOs) in a personalized cancer medicine setting. METHODS: Patient-derived colorectal cancer organoids were derived from tissue obtained from treatment-naïve patients undergoing surgical resection for the treatment of CRC. We examined the recapitulation of key histopathological, molecular, and phenotypic characteristics of the primary tumor. RESULTS: We created a bio-resource of PDCOs from primary and metastatic CRCs. Key histopathological features were retained in PDCOs when compared with the primary tumor. Additionally, a cohort of 12 PDCOs, and their corresponding primary tumors and normal sample, were characterized through whole exome sequencing and somatic variant calling. These PDCOs exhibited a high level of concordance in key driver mutations when compared with the primary tumor. CONCLUSIONS: Patient-derived colorectal cancer organoids recapitulate characteristics of the tissue from which they are derived and are a powerful tool for cancer research. Further research will determine their utility for predicting patient outcomes in a personalized cancer medicine setting.

Rectum versus colon: should malignant polyps be treated differently?

BACKGROUND: The management of malignant colorectal polyps removed at endoscopy remains controversial with patients either undergoing surgical resection or regular endoscopic surveillance. Lymph node (LN) metastases occur in 6-16% of patients with malignant polyps. This study assessed the rate of LN metastases in patients undergoing surgical resection for malignant polyps removed endoscopically to determine if there is a difference in the rate of LN metastases between colonic and rectal polyps. METHODS: A retrospective review of a prospectively maintained database was performed from 2010 to 2018. All patients who underwent surgical resection following endoscopic removal of a malignant colorectal polyp were reviewed. Clinical data including patient demographics and tumour characteristics were examined. RESULTS: A total of 177 patients underwent surgical resection in the study period. The median age at diagnosis was 65 years (range 22-88 years) with females comprising 52% of the patient cohort (n = 92/177). Polyps were located in the colon in 60.5% of cases with the remainder located in the rectum. The median number of LN harvested was 14 (range 0-44) with malignant LN (including a mesenteric tumour deposit) identified in 8.5% of resection specimens (n = 15/177). Malignant LNs were retrieved in 5.5% of right-sided tumours, 5.6% of left-sided tumours and 12.9% of rectal tumours (P = 0.090). CONCLUSION: A small proportion of patients with malignant polyps removed endoscopically will have LN metastases. The results of this study suggest that the tumour location might be a useful predictive marker; however, a further study with increased patient numbers is required to properly establish this finding.

Log odds of positive lymph nodes is prognostically equivalent to lymph node ratio in non-metastatic colon cancer.

BACKGROUND: Globally, colorectal cancer (CRC) is the third and second leading cancer in men and women respectively with 600,000 deaths per year. Traditionally, clinicians have relied solely on nodal disease involvement, and measurements such as lymph node ratio (LNR; the ratio of metastatic/positive lymph nodes to total number of lymph nodes examined), when determining patient prognosis in CRC. The log odds of positive lymph nodes (LODDS) is a logistic transformation formula that uses pathologic lymph node data to stratify survival differences among patients within a single stage of disease. This formula allows clinicians to identify whether patients with clinically aggressive tumours fall into higher-risk groups regardless of nodal positivity and can potentially guide adjuvant treatment modalities. The aim of this study was to investigate whether LODDS in colon cancer provides better prognostication compared to LNR. METHODS: A retrospective study of patients on the prospectively maintained Cabrini Monash University Department of Surgery colorectal neoplasia database, incorporating data from hospitals in Melbourne Australia, identified patients entered between January 2010 and March 2016. Association of LODDS and LNR with clinical variables were analysed. Disease-free (DFS) and overall (OS) survival were investigated with Cox regression and Kaplan-Meier survival analyses. RESULTS: There were 862 treatment episodes identified in the database (402 male, 47%). The median patient age was 73 (range 22-100 years). There were 799 colonic cancers and 63 rectosigmoid cancers. The lymph node yield (LNY) was suboptimal (< 12) in 168 patients (19.5%) (p = 0.05). The 5-year OS for the different LNR groups were 86, 91 and 61% (p < 0.001) for LNR0 (655 episodes), LNR1 (128 episodes) and LNR2 (78 episodes), respectively. For LODDS, they were 85, 91 and 61% (p < 0.001) in LODDS0 (569 episodes), LODDS1 (217 episodes) and LODDS2 (75 episodes) groups (p < 0.001). Overall survival rates were comparable between the LNR and LODDS group and for LNY < 12 and stage III patients when each were sub-grouped by LODDS and LNR. CONCLUSION: This study has shown for that the prognostic impact of LODDS is comparable to LNR for colon cancer patients. Accordingly, LNR is recommended for prognostication given its ease of calculation.

Mesenchymal Niche-Derived Neuregulin-1 Drives Intestinal Stem Cell Proliferation and Regeneration of Damaged Epithelium.

Epidermal growth factor (EGF) maintains intestinal stem cell (ISC) proliferation and is a key component of organoid growth media yet is dispensable for intestinal homeostasis, suggesting roles for multiple EGF family ligands in ISC function. Here, we identified neuregulin 1 (NRG1) as a key EGF family ligand that drives tissue repair following injury. NRG1, but not EGF, is upregulated upon damage and is expressed in mesenchymal stromal cells, macrophages, and Paneth cells. NRG1 deletion reduces proliferation in intestinal crypts and compromises regeneration capacity. NRG1 robustly stimulates proliferation in crypts and induces budding in organoids, in part through elevated and sustained activation of mitogen-activated protein kinase (MAPK) and AKT. Consistently, NRG1 treatment induces a proliferative gene signature and promotes organoid formation from progenitor cells and enhances regeneration following injury. These data suggest mesenchymal-derived NRG1 is a potent mediator of tissue regeneration and may inform the development of therapies for enhancing intestinal repair after injury.

Predictive factors of complete pathological response in patients with locally advanced rectal cancer.

PURPOSE: Patients with locally advanced rectal cancer who achieve pathologic complete response (pCR) following neoadjuvant therapy have better long-term outcomes and could be spared from the perioperative and long-term morbidity of rectal resection. The aim of this study was to identify factors that predict the ability to achieve pCR at completion of conventional neoadjuvant therapy, therefore determining their suitability for non-surgical management. METHODS: A retrospective analysis was performed on data obtained from a prospectively maintained colorectal neoplasia database. Patients treated for biopsy-proven primary rectal adenocarcinoma between January 1, 2010, and February 28, 2018, who received neoadjuvant radiotherapy or chemoradiotherapy and had undergone surgical resection, were included in this study. Five-year oncologic outcome data was also obtained for 144 patients. Clinicopathological tumour characteristics and treatment regimens were analysed for correlation to clinical outcome. RESULTS: Three hundred fifty-four patients met inclusion criteria for this study. We identified significant differences between patients achieving a pCR and those that did not for tumour type (adenocarcinoma vs. mucinous/signet ring; p = 0.008), pre-treatment serum CEA level (

Personalized Medicine-Current and Emerging Predictive and Prognostic Biomarkers in Colorectal Cancer.

Colorectal cancer (CRC) is the third most common cancer diagnosed worldwide and is heterogeneous both morphologically and molecularly. In an era of personalized medicine, the greatest challenge is to predict individual response to therapy and distinguish patients likely to be cured with surgical resection of tumors and systemic therapy from those resistant or non-responsive to treatment. Patients would avoid futile treatments, including clinical trial regimes and ultimately this would prevent under- and over-treatment and reduce unnecessary adverse side effects. In this review, the potential of specific biomarkers will be explored to address two key questions-1) Can the prognosis of patients that will fare well or poorly be determined beyond currently recognized prognostic indicators? and 2) Can an individual patient's response to therapy be predicted and those who will most likely benefit from treatment/s be identified? Identifying and validating key prognostic and predictive biomarkers and an understanding of the underlying mechanisms of drug resistance and toxicity in CRC are important steps in order to personalize treatment. This review addresses recent data on biological prognostic and predictive biomarkers in CRC. In addition, patient cohorts most likely to benefit from currently available systemic treatments and/or targeted therapies are discussed in this review.

Clostridioides difficile infection damages colonic stem cells via TcdB, impairing epithelial repair and recovery from disease.

Gastrointestinal infections often induce epithelial damage that must be repaired for optimal gut function. While intestinal stem cells are critical for this regeneration process [R. C. van der Wath, B. S. Gardiner, A. W. Burgess, D. W. Smith, PLoS One 8, e73204 (2013); S. Kozar et al., Cell Stem Cell 13, 626-633 (2013)], how they are impacted by enteric infections remains poorly defined. Here, we investigate infection-mediated damage to the colonic stem cell compartment and how this affects epithelial repair and recovery from infection. Using the pathogen Clostridioides difficile, we show that infection disrupts murine intestinal cellular organization and integrity deep into the epithelium, to expose the otherwise protected stem cell compartment, in a TcdB-mediated process. Exposure and susceptibility of colonic stem cells to intoxication compromises their function during infection, which diminishes their ability to repair the injured epithelium, shown by altered stem cell signaling and a reduction in the growth of colonic organoids from stem cells isolated from infected mice. We also show, using both mouse and human colonic organoids, that TcdB from epidemic ribotype 027 strains does not require Frizzled 1/2/7 binding to elicit this dysfunctional stem cell state. This stem cell dysfunction induces a significant delay in recovery and repair of the intestinal epithelium of up to 2 wk post the infection peak. Our results uncover a mechanism by which an enteric pathogen subverts repair processes by targeting stem cells during infection and preventing epithelial regeneration, which prolongs epithelial barrier impairment and creates an environment in which disease recurrence is likely.

Patient-Derived Colorectal Cancer Organoids Upregulate Revival Stem Cell Marker Genes following Chemotherapeutic Treatment.

Colorectal cancer stem cells have been proposed to drive disease progression, tumour recurrence and chemoresistance. However, studies ablating leucine rich repeat containing G protein-coupled receptor 5 (LGR5)-positive stem cells have shown that they are rapidly replenished in primary tumours. Following injury in normal tissue, LGR5+ stem cells are replaced by a newly defined, transient population of revival stem cells. We investigated whether markers of the revival stem cell population are present in colorectal tumours and how this signature relates to chemoresistance. We examined the expression of different stem cell markers in a cohort of patient-derived colorectal cancer organoids and correlated expression with sensitivity to 5-fluorouracil (5-FU) treatment. Our findings revealed that there was inter-tumour variability in the expression of stem cell markers. Clusterin (CLU), a marker of the revival stem cell population, was significantly enriched following 5-FU treatment and expression correlated with the level of drug resistance. Patient outcome data revealed that CLU expression is associated with both lower patient survival and an increase in disease recurrence. This suggests that CLU is a marker of drug resistance and may identify cells that drive colorectal cancer progression.

Molecular signature of interleukin-22 in colon carcinoma cells and organoid models.

Interleukin (IL)-22 activates STAT (signal transducer and activator of transcription) 3 and antiapoptotic and proproliferative pathways; but beyond this, the molecular mechanisms by which IL-22 promotes carcinogenesis are poorly understood. Characterizing the molecular signature of IL-22 in human DLD-1 colon carcinoma cells, we observed increased expression of 26 genes, including NNMT (nicotinamide N-methyltransferase, ≤10-fold) and CEA (carcinoembryonic antigen, ≤7-fold), both known to promote intestinal carcinogenesis. ERP27 (endoplasmic reticulum protein-27, function unknown, ≤5-fold) and the proinflammatory ICAM1 (intercellular adhesion molecule-1, ≤4-fold) were also increased. The effect on CEA was partly STAT3-mediated, as STAT3-silencing reduced IL-22-induced CEA by ≤56%. Silencing of CEA or NNMT inhibited IL-22-induced proliferation/migration of DLD-1, Caco-2, and SW480 colon carcinoma cells. To validate these results in primary tissues, we assessed IL-22-induced gene expression in organoids from human healthy colon and colon cancer patients, and from normal mouse small intestine and colon. Gene regulation by IL-22 was similar in DLD-1 cells and human and mouse healthy organoids. CEA was an exception with no induction by IL-22 in organoids, indicating the 3-dimensional organization of the tissue may produce signals absent in 2D cell culture. Importantly, augmentation of NNMT was 5-14-fold greater in human cancerous compared to normal organoids, supporting a role for NNMT in IL-22-mediated colon carcinogenesis. Thus, NNMT and CEA emerge as mediators of the tumor-promoting effects of IL-22 in the intestine. These data advance our understanding of the multifaceted role of IL-22 in the gut and suggest the IL-22 pathway may represent a therapeutic target in colon cancer.

The role of preoperative CEA in the management of colorectal cancer: A cohort study from two cancer centres.

BACKGROUND: The primary aim of this study was to investigate whether a preoperative elevation in serum CEA is an independent prognostic factor for both 5-year overall and disease-free survival within an Australian patient cohort. MATERIALS AND METHODS: A retrospective study of a prospectively maintained colorectal neoplasia database for patients between January 2010 and June 2016 was performed. Patients were categorized into two groups according to the preoperative serum CEA level: low (<2.5), high CEA (≥2.5), and elevated (≥5 ng/ml); and further stratified by disease stage. Inclusion criteria were patients having had a resection for either a colonic or upper third rectal adenocarcinoma and with a preoperative CEA value. Data on patient demographics, mortality, and morbidity and survival were compiled. Five-year estimates of overall (OS) and disease-free survival (DFS) were assessed. RESULTS: 623 patients met the inclusion criteria. The median patient age was 73 (range 22-97) and 55% female (n = 340). There were 572 colonic cancers and 51 rectal cancers. The median follow-up time was 25 months (range 1-71). Eight patients (1%) had a local recurrence and 62 patients (10%) had evidence of metastatic disease after the initial curative resection. The 5-year OS and DFS rates for patients with CEA level <2.5 ng/ml were 85% and 86% respectively, which were higher than those with CEA level ≥2.5 ng/ml (73% and 79% respectively). Independent predictors of recurrence were a CEA ≥5 ng/ml (HR 1.8; 95% CI 1.09-3.00; p = 0.002) and stage II (HR 5.33; 95% CI 1.59-17.90; p = 0.007) and stage III (HR 10.91; 95% CI 3.34-35.60; p=<0.001). A CEA ≥5 ng/ml was associated with a higher risk of death (HR 1.79; 95% CI 1.00-3.19; p = 0.046). CONCLUSION: Preoperative CEA levels were associated with age, BMI, ASA and tumour stage. Overall, CEA remains a reliable predictor of recurrence and survival after curative surgery in patients with colorectal cancer.

The ALCCaS Trial: A Randomized Controlled Trial Comparing Quality of Life Following Laparoscopic Versus Open Colectomy for Colon Cancer.

BACKGROUND: This study reports the quality-of-life assessment of the ALCCaS trial. The ALCCaS trial compared laparoscopic and open resection for colon cancer. It reported equivalence of survival at 5 years. Quality of life was measured as a secondary outcome. OBJECTIVE: This study aimed to report on the quality of life data of the ALCCaS Trial. DESIGN: This study reports a randomized controlled trial comparing laparoscopic with open colonic resection. SETTINGS: The study was conducted in Australasia. PATIENTS: Patients with a single adenocarcinoma of the right, left, or sigmoid colon, presenting for elective treatment, were eligible for randomization. INTERVENTIONS: Open and laparoscopic colonic resections were performed. MAIN OUTCOME MEASURES: Patient symptoms and quality of life were measured using the Symptoms Distress Scale, the Quality of Life Index, and the Global Quality of Life Score preoperatively, and at 2 days, 2 weeks, and 2 months postoperatively. RESULTS: Of the 592 patients enrolled in ALCCaS, 425 completed at least 1 quality-of-life measure at 4 time points (71.8% of cohort). Those who received the laparoscopic intervention had better quality of life postoperatively in terms of the Symptoms Distress Scale (p < 0.01), Quality of Life Index (p < 0.01), and Global Quality of Life (p < 0.01). In intention-to-treat analyses, those assigned to laparoscopic surgery had a better quality of life postoperatively in terms of the Symptoms Distress Scale (p < 0.01) and Quality of Life Index (p < 0.01), whereas Global Quality of Life was not significant (p = 0.056). The subscales better for laparoscopic resection at all 3 postoperative time points were appetite, insomnia, pain, fatigue, bowel, daily living, and health (p < 0.05). LIMITATIONS: The primary limitation was the different response rates for the 3 quality-of-life measures. CONCLUSIONS: There was a short-term gain in quality of life maintained at 2 months postsurgery for those who received laparoscopic relative to open colonic resection. See Video Abstract at http://links.lww.com/DCR/A691.