Developing a curriculum for advanced fellowship training in complex cancer for the UK.

AIM: Surgery for complex colorectal cancer is elaborate: preoperative assessment, patient selection, radiological interpretation, operative strategy, operative technical skills, operative standardization, postoperative care and management of complications are all critical components. Given this complexity, training that encompasses all these crucial aspects to generate suitably edified surgeons is essential. To date, no curriculum exists to guide training in advanced and recurrent pelvic malignancy, particularly for complex colorectal cancer. Such a curriculum would potentially offer numerous advantages, not only for individual surgeons but also for research, governance, international collaboration and benchmarking. The aim of this study was to design and develop a framework for a curriculum for fellowship training in complex colorectal cancer that encompasses pelvic exenteration surgery. METHOD: Kern described a six-step method for curriculum design that is now widely adopted in medical education. Our study utilizes steps 1-4 of Kern's method to develop a syllabus and assessment framework for curriculum development for fellowship training in complex colorectal cancer encompassing pelvic exenteration. A literature review was conducted to address step 1, followed by targeted needs assessment in step 2 by conducting focus groups with trainees, fellows and experts to identify learning needs and goals with objective setting for step 3. An expert consensus group then voted on these recommendations and developed educational strategy recommendations as step 4. For the purposes of brevity, 'pelvic exenteration' in the text is taken to also encompass extended and multivisceral resections that fall under the remit of complex [colorectal] cancer. RESULTS: Step 1 of Kern's method identified a gap in the literature on curricula in complex cancer surgery. Step 2 identified key areas regarded as learning needs by trainees, including anatomy, hands-on experience and case volume. Step 3 defined the goals and objectives of a fellowship curriculum, defined in six domains including theoretical knowledge, decision-making, technical skills, postoperative management and continuing professional development. Finally, as a prelude to stages 5 and 6, a strategy for implementation and for feedback and assessment was agreed by an expert consensus meeting that defined case volume (a minimum of 20 pelvic exenteration operations within a fellowship period) and coverage of this syllabus with derived metrics. CONCLUSIONS: Our working group has developed a curriculum framework for advanced fellowship training in complex cancer in the UK. Validation is needed through implementation, and affirmation of its utility, both nationally and internationally, must be sought.

Immune responses to citrullinated and homocitrullinated peptides in healthy donors are not restricted to the HLA SE shared allele and can be selected into the memory pool.

Citrullination and homocitrullination are stress induced post-translational modifications (siPTMs) which can be recognized by T cells. Peripheral blood mononuclear cells isolated from healthy donors and rheumatoid arthritis (RA) patients were stimulated with nine siPTM-peptides. CD45RA/CD45RO depletion was employed to determine if peptide-specific responses are naïve or memory. Human leucocyte antigen (HLA)-DP4 and HLA-DR4 transgenic mice were immunized with siPTM-peptides and immune responses were determined with ex vivo ELISpot assays. The majority (24 out of 25) of healthy donors showed CD4 T cell-specific proliferation to at least 1 siPTM-peptide, 19 to 2 siPTM-peptides, 14 to 3 siPTM-peptides, 9 to 4 siPTM-peptides, 6 to 5 siPTM-peptides and 4 to 6 siPTM-peptides. More donors responded to Vim28-49cit (68%) and Bip189-208cit (75%) compared with Vim415-433cit (33%). In RA patients, the presentation of citrullinated epitopes is associated with HLA-SE alleles; however, we witnessed responses in healthy donors who did not express the SE allele. The majority of responding T cells were effector memory cells with a Th1/cytotoxic phenotype. Responses to Vim28-49cit and Eno241-260cit originated in the memory pool, while the response to Vim415-433cit was naïve. In the HLA-DP4 and HLA-DR4 transgenic models, Vim28cit generated a memory response. Peptide-specific T cells were capable of Epstein-Barr virus transformed lymphoblastoid cell line recognition suggesting a link with stress due to infection. These results suggest siPTM-peptides are presented under conditions of cellular stress and inflammation and drive cytotoxic CD4 T cell responses that aid in the removal of stressed cells. The presentation of such siPTM-peptides is not restricted to HLA-SE in both humans and animal models.

Protocol for the UK cohort study to investigate the prevention of parastomal hernia (the CIPHER study).

AIM: Abdominal surgery sometimes necessitates the creation of a stoma, which can cause future complications including parastomal hernia (PSH), an incisional hernia adjacent to and related to the stoma. PSH affects approximately 40% of patients within 2 years of stoma formation. Complications of PSH reduce a patient's quality of life and can be severe (e.g. bowel obstruction). PSHs are difficult to manage and can recur after surgical repair. Therefore, it is very important to prevent a PSH. Surgeons create stomas in different ways and both patient and surgical factors are believed to influence the development of PSH. The aim of the CIPHER study is to investigate the influence of different surgical techniques on the development of PSH. METHOD: The UK cohort study to investigate the prevention of parastomal hernia (the CIPHER study) aims to recruit 4000 patients undergoing elective or expedited surgery with the intention of forming an ileostomy or colostomy, irrespective of the primary indication for the planned surgery. For each patient, surgeons will describe their methods of trephine formation, mesh reinforcement of the stoma trephine, use of the stoma as a specimen extraction site and wound closure. The primary outcome will be incident PSH during follow-up, defined as symptoms of PSH (custom-designed questionnaire) and anatomical PSH, ascertained by independent reading of usual care CT scans. Secondary outcomes will include surgical site infection, the Comprehensive Complication Index, quality of life (EQ-5D-5L and SF-12), PSH repair and use of NHS resources. RESULTS: Results of the study will be submitted for publication in peer-reviewed journals. All publications relating to the results of CIPHER will use a corporate authorship, 'The CIPHER Study Investigators' with named writing committee members. CONCLUSION: The CIPHER study will be the first to investigate detailed surgical methods of stoma formation in a large, representative cohort of patients with a range of primary indications, both cancer and noncancer.

A systematic review of new treatments for cryptoglandular fistula in ano.

AIM: In 2007 the ACPGBI published a position statement on the management of cryptoglandular fistula in ano. Over the last seven years a number of new treatments have been developed and the aim of this systematic review was to assess their effectiveness. METHOD: A systematic review of all English language literature relevant to novel treatment strategies for cryptoglandular fistula in ano, published between 1 January 2007 and 31 Dec 2014 was carried out using MEDLINE (PubMed and Ovid), EMBASE (Ovid) and the Cochrane Library of Systematic Reviews/Controlled Trials for relevant literature. Technical notes, commentaries, letters and meeting abstracts were excluded. The different treatments were assessed with regards to fistula closure rate in relation to length of follow up and reported complications. RESULTS: Seventy potential articles published between 1 January 2007 and 31 December 2014 were identified from the initial literature search. Twenty-one articles were included for final analysis although only two were randomized controlled trials, the remainder being retrospective or prospective series. CONCLUSION: This systematic review has demonstrated that whilst there have been technological advances to treat complex cryptoglandular fistula in ano, these are in an early stage of evolution and although early results were promising they are difficult to reproduce. Longer follow up data is not currently available and these treatments should not be introduced without further evidence.

Rituximab: modes of action, remaining dispute and future perspective.

Less than two decades ago, immunotherapy joined chemotherapy and radiotherapy as an effective approach for the treatment of cancer. The anti-CD20 monoclonal antibody, rituximab, is now used to treat almost all types of non-Hodgkin's B-cell lymphomas, and it could be useful in the treatment of other diseases with B-cell involvement. Upon binding, rituximab induces death of the target cells. It seems to act not only by activating immune system defense mechanisms such as complement-dependent and antibody-dependent cellular cytotoxicity, but also by inducing direct cell death. In this paper, we review current knowledge on rituximab mechanisms of action, with particular attention to its direct effects, and also highlight potential future avenues of research.

Genetic, epigenetic and environmental factors in diverticular disease: systematic review.

BACKGROUND: Diverticulosis is a normal anatomical variant of the colon present in more than 70% of the westernized population over the age of 80. Approximately 3% will develop diverticulitis in their lifetime. Many patients present emergently, suffer high morbidity rates and require substantial healthcare resources. Diverticulosis is the most common finding at colonoscopy and has the potential for causing a significant morbidity rate and burden on healthcare. There is a need to better understand the aetiology and pathogenesis of diverticular disease. Research suggests a genetic susceptibility of 40-50% in the formation of diverticular disease. The aim of this review is to present the hypothesized functional effects of the identified gene loci and environmental factors. METHODS: A systematic literature review was performed using PubMed, MEDLINE and Embase. Medical subject headings terms used were: 'diverticular disease, diverticulosis, diverticulitis, genomics, genetics and epigenetics'. A review of grey literature identified environmental factors. RESULTS: Of 995 articles identified, 59 articles met the inclusion criteria. Age, obesity and smoking are strongly associated environmental risk factors. Intrinsic factors of the colonic wall are associated with the presence of diverticula. Genetic pathways of interest and environmental risk factors were identified. The COLQ, FAM155A, PHGR1, ARHGAP15, S100A10, and TNFSF15 genes are the strongest candidates for further research. CONCLUSION: There is increasing evidence to support the role of genomics in the spectrum of diverticular disease. Genomic, epigenetic and omic research with demographic context will help improve the understanding and management of this complex disease.

Did the 'Be Clear on Bowel Cancer' public awareness campaign pilot result in a higher rate of cancer detection?

OBJECTIVES: To assess the impact of a 7-week public bowel cancer awareness campaign pilot by reviewing the number of 2-week referrals from general practitioners (GPs) to hospital, endoscopic procedures and new cancers diagnosed throughout the five acute hospitals in The Peninsular Cancer Network, UK. DESIGN: A retrospective before and after study. SETTING: The Peninsula Cancer Network in the South West of England, UK. MAIN OUTCOME MEASURES: For the period July 2010-July 2011, data were collected on the number of 2-week referrals, number of endoscopic procedures performed and number of new cancers diagnosed. The average for the 6 months before the campaign was compared with the immediate 3 months and then the fourth to sixth months following the campaign. Student's t test was used to compare the means of the three groups. RESULTS: There was a statistically significant increase in the number of 2-week referrals from GPs to hospital in the 3 months following the campaign but this effect disappeared after that. There was no statistical increase in the number of endoscopic procedures or new cancers diagnosed following the awareness campaign. CONCLUSIONS: The pilot 'Be Clear on Cancer' awareness campaign had a significant effect on the number of patients being referred from GPs to hospital; however, the effect was short lived and had returned to baseline by 3 months. The campaign had no effect on the number of new cancers diagnosed, which was the stated underlying aim of the pilot.

Exfoliated colonocyte DNA levels and clinical features in the diagnosis of colorectal cancer: a cohort study in patients referred for investigation.

AIM: Selection of patients for investigation of suspected colorectal cancer is difficult. One possible improvement may be to measure DNA isolated from exfoliated cells collected from the rectum. METHOD: This was a cohort study in a surgical clinic. Participants were aged ≥40 years and referred for investigation of suspected colorectal cancer. Exclusion criteria were inflammatory bowel disease, previous gastrointestinal malignancy, or recent investigation. A sample of the mucocellular layer of the rectum was taken with an adapted proctoscope (the Colonix system). Haemoglobin, mean cell volume, ferritin, carcino-embryonic antigen and faecal occult bloods were tested. Analysis was by logistic regression. RESULTS: Participation was offered to 828 patients, of whom 717 completed the investigations. Three were lost to follow up. Seventy-two (10%) had colorectal cancer. Exfoliated cell DNA was higher (P<0.001) in cancer (median 5.4 µg/ml [inter-quartile range 1.8,12]) compared with those without cancer (2.0 µg/ml [IQR 0.78,5.5]). Seven variables were independently associated with cancer, including age (odds ratio [OR], 1.05; 95% confidence interval [CI], 1.02,1.08; P<0.001) DNA (OR, 1.05; CI, 1.01,3.6; P=0.01), mean cell volume (OR, 0.93; CI, 0.89,0.97; P=0.001), carcino-embryonic antigen 1.02 per µg/l (CI, 1.00,1.04; P=0.02), male sex (OR, 2.0; CI, 1.1,3.6; P=0.02), rectal bleeding (OR, 2.4; CI, 1.3,4.5; P=0.007) and positive faecal occult blood (OR, 6.7; CI, 3.4, 13; P<0.001). The area under the receiver-operating characteristic curve for the DNA score was 0.65 (0.58-0.72) and for the seven variable model 0.88 (CI, 0.84-0.92). CONCLUSION: Quantification of exfoliated DNA from rectal cellular material has promise in the diagnosis of colorectal cancer, but this requires confirmation in a larger study.

Biological meshes: a review of their use in abdominal wall hernia repairs.

PURPOSE: Biological meshes are mostly used in infected fields within complex abdominal wall hernia repairs. There is no consensus, however, on the most appropriate material to be used in a given situation. METHODS: A literature review of published articles reporting the utilization of biological meshes in ventral/incisional hernia repair was conducted. Data were analyzed to compare the recurrence rates obtained with biological meshes. MAIN FINDINGS: Only a few prospective comparative studies were identified. Most publications relate to AlloDerm®, Permacol™ and Surgisis™ with data from other meshes insufficient to draw conclusions. AlloDerm has a 0-100% recurrence rate among studies. It compares poorly with Surgisis and results in an unfavorable outcome when used as a 'bridge prosthesis'. Permacol has consistent recurrence rates of 0-15%, whatever the patients' profiles or the context of infected fields, when considering the most relevant studies. The Surgisis results are more conflicting: the mesh exhibits low recurrence rates in clean fields, but in infected fields the recurrence rate is up to 39%. CONCLUSION: Taken together, these studies suggest that the cross-linked mesh, Permacol has the lowest failure rate and the longest time to failure, particularly in contaminated or infected fields. However, this data should be confirmed by large prospective randomized studies.

Citrullinated glucose-regulated protein 78 is a candidate target for melanoma immunotherapy.

Introduction: Post translational modification of proteins plays a significant role in immune recognition. In particular the modification of arginine to citrulline which is mediated by PAD enzymes is increased during cellular stress (autophagy) which permits the presentation of modified epitopes upon MHC class II molecules for recognition by CD4 T cells. Citrullination also occurs in tumour cells as a result of continuous environmental stresses and increased autophagy. We have shown in animal models the efficient stimulation of citrullinated epitope specific CD4 T cells resulting in dramatic elimination/regression of tumours. The ER chaperone glucose-regulated protein 78 (GRP78) is known to also be required for stress-induced autophagy and is directly linked to autophagosome formation. GRP78 is known to be highly expressed by many tumour types. In this study we investigate the potential of targeting citrullinated GRP78 for cancer therapy. Methods: A citrullinated GRP78 specific antibody was used to assess citrullinated GRP78 expression in murine and human tumour cells by flow cytometry. Five peptides were selected and used to vaccinate HLA transgenic mice and immune responses were characterised by ex vivo cytokine ELISpot assay. T cell repertoire in humans was assessed through proliferation assays and cytokine ELISpot assay. Citrullinated peptide was identified in murine B16 melanoma by mass spectrometry and the peptide vaccine was assessed for tumour therapy in a mouse melanoma model. Results: We show the identification CD4 T cell responses to one citrullinated GRP78 epitope that are restricted through HLA DP*0401 and HLA-DR*0101 alleles. This peptide is detected by mass spectrometry in B16 melanoma grown in vivo and citrulline specific CD4 responses to two peptides spanning this epitope mediate efficient therapy of established B16 melanoma tumours in HHDII/DP4 (p<0.0001) transgenic mouse model. Finally, we demonstrate the existence of a repertoire of responses to the citrullinated GRP78 peptide in healthy individuals (p=0.0023) with 13/17 (76%) individuals showing a response to this peptide. Conclusion: We propose that citrullinated GRP78 is a candidate tumour antigen and vaccination against citrullinated GRP78 may provide a promising tumour therapy approach.

Vaccine Can Induce CD4-Mediated Responses to Homocitrullinated Peptides via Multiple HLA-Types and Confer Anti-Tumor Immunity.

Homocitrullination is the post translation modification (PTM) of the amino acid lysine to homocitrulline also referred to as carbamylation. This PTM has mainly been studied in relation to autoimmune diseases including rheumatoid arthritis. Homocitrullination of lysines alters their charge which can lead to generation of neoepitopes that are differentially presented by MHC-II and induce modification-specific immune responses. Homocitrullination is often considered a process which triggers autoimmune disease by bypassing self-tolerance however, we suggest that homocitrullination may also have an alternative role in immune responses including protection against cancer. Here we demonstrate that immune responses to homocitrullinated peptides from three different proteins can be induced via multiple HLA-types. Immunization of Balb/c or HLA-transgenic DR4 and DR1 mice can induce modification-specific CD4 mediated IFNγ responses. Healthy human donors show a clear repertoire for the homocitrullinated Vimentin peptide (Vim116-135Hcit), with modification-specific and oligoclonal responses. Importantly, in vivo homocitrulline specific Vim116-135Hcit,Cyk8 371-388Hcit and Aldo 140-157Hcit responses are able to confer an anti-tumor effect in the murine B16 melanoma model. The Vim116-135Hcit anti-tumor response was dependent upon tumor expression of MHC-II suggesting the direct recognition of PTMs on tumor is an important anti-tumor mechanism. Cancer patients also have a CD4 repertoire for Vim116-135Hcit. Together these results suggest that homocitrulline-specific immune responses can be generated in healthy mice and detected in human donors through a variety of HLA-restrictions. Immunization can induce responses to Vim116-135Hcit,Aldolase 140-157Hcit and Cyk8 371-388Hcit which provide anti-tumor therapy across several HLA-types. Our results advance our understanding of homocitrulline-specific immune responses, with implications for a number of fields beyond autoimmunity, including tumor immune surveillance.

PAD-2-mediated citrullination of nucleophosmin provides an effective target for tumor immunotherapy.

BACKGROUND: The enzymatic conversion of arginine to citrulline is involved in gene and protein regulation and in alerting the immune system to stressed cells, including tumor cells. Nucleophosmin (NPM) is a nuclear protein that plays key roles in cellular metabolism including ribosome biogenesis, mRNA processing and chromatin remodeling and is regulated by citrullination. In this study, we explored if the same citrullinated arginines within NPM are involved in gene regulation and immune activation. METHODS: HLA-DP4 and HLA-DR4 transgenic mice were immunized with 22 citrullinated NPM overlapping peptides and immune responses to the peptides were assessed by ex vivo ELISpot assays. Antitumor immunity of NPM targeted vaccination was assessed by challenging transgenic mice with B16F1 HHDII/iDP4, B16F1 HHDII/PAD2KOcDP4, B16F1 HHDII and Lewis lung carcinoma cells/cDP4 cells subcutaneously. Peripheral blood mononuclear cells isolated from healthy donors were stimulated with NPM266-285cit peptides with/without CD45RO+memory cell depletion to assess if the responses in human were naïve or memory. RESULTS: In contrast to NPM regulation, which is mediated by peptidylarginine deiminase (PAD4) citrullination of arginine at position 197, only citrullinated NPM266-285 peptide induced a citrulline-specific CD4 T cell response in transgenic mice models expressing human HLA-DP4 or HLA-DR4. Vaccinations with the NPM266-285cit peptide stimulated antitumor responses that resulted in dramatic tumor therapy, greatly improved survival, and protected against rechallenge without further vaccination. The antitumor response was lost if MHCII expression on the tumor cells was knocked out demonstrating direct presentation of the NPM266-285cit epitope in tumors. This antitumor response was lost in B16 tumors lacking PAD2 enzyme indicating NPM266cit is citrullinated by PAD2 in this model. Assessment of the T cell repertoire in healthy individuals and patients with lung cancer also showed CD4 T cells that respond to NPM266-285cit. The proliferative CD4 responses displayed a Th1 profile as they were accompanied with increased IFNγ and granzyme B expression. Depletion of CD45RO+ memory cells prior to stimulation suggested that responses originated from a naïve population in healthy donors. CONCLUSION: This study indicates PAD2 can citrullinate the nuclear antigen NPM at position 277 which can be targeted by CD4 T cells for antitumor therapy. This is distinct from PAD4 citrullination of arginine 197 within NPM which results in its transport from the nucleoli to the nucleoplasm.

Quality of life in restorative versus non-restorative resections for rectal cancer: systematic review.

BACKGROUND: Low rectal cancers could be treated using restorative (anterior resection, AR) or non-restorative procedures with an end/permanent stoma (Hartmann's, HE; or abdominoperineal excision, APE). Although the surgical choice is determined by tumour and patient factors, quality of life (QoL) will also influence the patient's future beyond cancer. This systematic review of the literature compared postoperative QoL between the restorative and non-restorative techniques using validated measurement tools. METHODS: The review was registered on PROSPERO (CRD42020131492). Embase and MEDLINE, along with grey literature and trials websites, were searched comprehensively for papers published since 2012. Inclusion criteria were original research in an adult population with rectal cancer that reported QoL using a validated tool, including the European Organization for Research and Treatment of Cancer QLQ-CR30, QLQ-CR29, and QLQ-CR38. Studies were included if they compared AR with APE (or HE), independent of study design. Risk of bias was assessed using the Risk Of Bias In Non-Randomized Studies of Interventions (ROBINS-I) tool. Outcomes of interest were: QoL, pain, gastrointestinal (GI) symptoms (stool frequency, flatulence, diarrhoea and constipation), and body image. RESULTS: Nineteen studies met the inclusion criteria with a total of 6453 patients; all papers were observational and just four included preoperative evaluations. There was no identifiable difference in global QoL and pain between the two surgical techniques. Reported results regarding GI symptoms and body image documented similar findings. The ROBINS-I tool highlighted a significant risk of bias across the studies. CONCLUSION: Currently, it is not possible to draw a firm conclusion on postoperative QoL, pain, GI symptoms, and body image following restorative or non-restorative surgery. The included studies were generally of poor quality, lacked preoperative evaluations, and showed considerable bias in the data.

Root-cause analyses of missed opportunities for the diagnosis of colorectal cancer in patients with inflammatory bowel disease.

BACKGROUND: Colonoscopic surveillance in patients with inflammatory bowel disease (IBD) leads to earlier detection of colorectal cancer (CRC) and reduces CRC-associated mortality. However, it is limited by poor adherence in practice. AIM: To identify missed opportunities to detect IBD-associated CRC at our hospital METHODS: We undertook root-cause analyses to identify patients with missed opportunities to diagnose IBD-associated CRC. We matched patients with IBD-associated CRC to patients with CRC in the general population to identify differences in staging at diagnosis and clinical outcomes. RESULTS: Compared with the general population, patients with IBD were at increased risk of developing CRC (odds ratio 2.7 [95% CI 1.6-3.9], P < 0.001). The mean incidence of IBD-associated CRC between 1998 and 2019 was 165.4 (IQR 130.4-199.4) per 100 000 patients and has not changed over the last 20 years. Seventy-eight patients had IBD-associated CRC. Forty-two (54%) patients were eligible for CRC surveillance: 12% (5/42) and 10% (4/42) patients were diagnosed with CRC at an appropriately timed or overdue surveillance colonoscopy, respectively. Interval cancers occurred in 14% (6/42) of patients; 64% (27/42) of patients had a missed opportunity for colonoscopic surveillance where root-cause analyses demonstrated that 10/27 (37%) patients known to secondary care had not been offered surveillance. Four (15%) patients had a delayed diagnosis of CRC due to failure to account for previous colonoscopic findings. Seventeen (63%) patients were managed by primary care including seven patients discharged from secondary care without a surveillance plan. Matched case-control analysis did not show significant differences in cancer staging or 10-year survival outcomes. CONCLUSION: The incidence of IBD-associated CRC has remained static. Two-thirds of patients eligible for colonoscopic surveillance had missed opportunities to diagnose CRC. Surveillance programmes without comprehensive and fully integrated recall systems across primary and secondary care are set to fail.

Homocitrullination of lysine residues mediated by myeloid-derived suppressor cells in the tumor environment is a target for cancer immunotherapy.

BACKGROUND: Homocitrullination is the post-translational modification of lysine that is recognized by T cells. METHODS: This study identified homocitrullinated peptides from aldolase, enolase, cytokeratin and binding immunoglobulin protein and used human leukocyte antigen (HLA) transgenic mice to assess immunogenicity by enzyme-linked immunosorbent spot assay. Vaccine efficacy was assessed in tumor therapy studies using HLA-matched B16 melanoma expressing constitutive or interferon γ (IFNγ)-inducible major histocompatibility complex class II (MHC-II) as represented by most human tumors. To determine the mechanism behind the therapy, immune cell infiltrates were analyzed using flow cytometry and therapy studies in the presence of myeloperoxidase (MPO) inhibitor and T-cell depletion performed. We assessed the T-cell repertoire to homocitrullinated peptides in patients with cancer and healthy donors using flow cytometry. RESULTS: Homocitrulline (Hcit) peptide vaccination stimulated strong CD4 T-cell responses and induced significant antitumor therapy in an established tumor model. The antitumor response was dependent on CD4 T cells and the effect was driven mainly via direct tumor recognition, as responses were only observed if the tumors were induced to express MHC-II. In vitro proliferation assays show that healthy donors and patients with cancer have an oligoclonal CD4 T-cell repertoire recognizing homocitrullinated peptides. Inhibition of cyanate generation, which mediates homocitrullination, by MPO inhibition reduced tumor therapy by the vaccine induced T cells (p=0.0018). Analysis of the tumor microenvironment (TME) suggested that myeloid-derived suppressor cells (MDSCs) were a potential source of MPO. The selected B16 melanoma model showed MDSC infiltration and was appropriate to see if the Hcit vaccine could overcome the immunosuppression associated with MDSCs. The vaccine was very effective (90% survival) as the induced CD4 T cells directly targeted the homocitrullinated tumor and likely reversed the immunosuppressive environment. CONCLUSION: We propose that MPO, potentially produced by MDSCs, catalyzes the buildup of cyanate in the TME which diffuses into tumor cells causing homocitrullination of cytoplasmic proteins which are degraded and, in the presence of IFNγ, presented by MHC-II for direct CD4 T-cell recognition. Homocitrullinated proteins are a new target for cancer vaccines and may be particularly effective against tumors containing high levels of MPO expressing MDSCs.

Characteristics of Early-Onset vs Late-Onset Colorectal Cancer: A Review.

Importance: The incidence of early-onset colorectal cancer (younger than 50 years) is rising globally, the reasons for which are unclear. It appears to represent a unique disease process with different clinical, pathological, and molecular characteristics compared with late-onset colorectal cancer. Data on oncological outcomes are limited, and sensitivity to conventional neoadjuvant and adjuvant therapy regimens appear to be unknown. The purpose of this review is to summarize the available literature on early-onset colorectal cancer. Observations: Within the next decade, it is estimated that 1 in 10 colon cancers and 1 in 4 rectal cancers will be diagnosed in adults younger than 50 years. Potential risk factors include a Westernized diet, obesity, antibiotic usage, and alterations in the gut microbiome. Although genetic predisposition plays a role, most cases are sporadic. The full spectrum of germline and somatic sequence variations implicated remains unknown. Younger patients typically present with descending colonic or rectal cancer, advanced disease stage, and unfavorable histopathological features. Despite being more likely to receive neoadjuvant and adjuvant therapy, patients with early-onset disease demonstrate comparable oncological outcomes with their older counterparts. Conclusions and Relevance: The clinicopathological features, underlying molecular profiles, and drivers of early-onset colorectal cancer differ from those of late-onset disease. Standardized, age-specific preventive, screening, diagnostic, and therapeutic strategies are required to optimize outcomes.

Patients with low rectal cancer treated by abdominoperineal excision have worse tumors and higher involved margin rates compared with patients treated by anterior resection.

PURPOSE: Patients with low rectal cancer have worse outcomes compared to those with upper rectal cancer. Reports suggest that low anterior resection may be oncologically superior to abdominoperineal excision, although no good evidence exists to support this. We looked at a recent series of patients with low rectal cancer to explore some of the issues. METHODS: We analyzed 153 patients from the MERCURY study with low rectal cancer (

Major surgery induces acute changes in measured DNA methylation associated with immune response pathways.

Surgery is an invasive procedure evoking acute inflammatory and immune responses that can influence risk for postoperative complications including cognitive dysfunction and delirium. Although the specific mechanisms driving these responses have not been well-characterized, they are hypothesized to involve the epigenetic regulation of gene expression. We quantified genome-wide levels of DNA methylation in peripheral blood mononuclear cells (PBMCs) longitudinally collected from a cohort of elderly patients undergoing major surgery, comparing samples collected at baseline to those collected immediately post-operatively and at discharge from hospital. We identified acute changes in measured DNA methylation at sites annotated to immune system genes, paralleling changes in serum-levels of markers including C-reactive protein (CRP) and Interleukin 6 (IL-6) measured in the same individuals. Many of the observed changes in measured DNA methylation were consistent across different types of major surgery, although there was notable heterogeneity between surgery types at certain loci. The acute changes in measured DNA methylation induced by surgery are relatively stable in the post-operative period, generally persisting until discharge from hospital. Our results highlight the dramatic alterations in gene regulation induced by invasive surgery, primarily reflecting upregulation of the immune system in response to trauma, wound healing and anaesthesia.