Science, Medicine, and Cytology: an educational program of the Diversity, Equity, and Inclusion Committee of the American Society of Cytopathology.

INTRODUCTION: As our field of pathology continues to grow, our trainee numbers are on the decline. To combat this trend, the ASC Diversity, Equity, and Inclusion Committee established the Science, Medicine, and Cytology SumMer Certificate program to improve exposure to pathology/cytopathology with a focus on diversity, equity, and inclusion. Herein, we report our findings of the first 2 years of the program. MATERIALS AND METHODS: An online course was developed targeting students who are underrepresented in medicine at the high school and college level. It consisted of several didactic sessions, presenting the common procedures involving cytopathologists and cytologists. Interviews with cytopathologists were also included. Participants were surveyed for demographic information and provided course evaluations. RESULTS: In the first year of the program (2021), 34 participants completed the program, which increased to 103 in 2022. In both years there was a diversity in participant demographic backgrounds; however, only a minority of participants self-identified as being underrepresented in medicine. A vast majority (>85%) of participants in both years were high school or college students. In 2021, 100% of participants stated that the program format was effective and 94% thought the content was appropriate for their level of education; in 2022 the results were similar. In 2021, 66% considered health care as a potential career; this value increased in 2022 to 83%. In 2021 and 2022, 31% and 38%, respectively, considered cytology as a career. CONCLUSIONS: Evaluations were excellent, generating interest in cytopathology. Barriers in reaching underrepresented minorities exist and additional work is needed. Expansion to a wider audience may increase outreach.

Multi-scale and cross-dimensional TMS mapping: A proof of principle in patients with Parkinson's disease and deep brain stimulation.

Introduction: Transcranial magnetic stimulation (TMS) mapping has become a critical tool for exploratory studies of the human corticomotor (M1) organization. Here, we propose to gather existing cutting-edge TMS-EMG and TMS-EEG approaches into a combined multi-dimensional TMS mapping that considers local and whole-brain excitability changes as well as state and time-specific changes in cortical activity. We applied this multi-dimensional TMS mapping approach to patients with Parkinson's disease (PD) with Deep brain stimulation (DBS) of the sub-thalamic nucleus (STN) ON and OFF. Our goal was to identifying one or several TMS mapping-derived markers that could provide unprecedent new insights onto the mechanisms of DBS in movement disorders. Methods: Six PD patients (1 female, mean age: 62.5 yo [59-65]) implanted with DBS-STN for 1 year, underwent a robotized sulcus-shaped TMS motor mapping to measure changes in muscle-specific corticomotor representations and a movement initiation task to probe state-dependent modulations of corticospinal excitability in the ON (using clinically relevant DBS parameters) and OFF DBS states. Cortical excitability and evoked dynamics of three cortical areas involved in the neural control of voluntary movements (M1, pre-supplementary motor area - preSMA and inferior frontal gyrus - IFG) were then mapped using TMS-EEG coupling in the ON and OFF state. Lastly, we investigated the timing and nature of the STN-to-M1 inputs using a paired pulse DBS-TMS-EEG protocol. Results: In our sample of patients, DBS appeared to induce fast within-area somatotopic re-arrangements of motor finger representations in M1, as revealed by mediolateral shifts of corticomuscle representations. STN-DBS improved reaction times while up-regulating corticospinal excitability, especially during endogenous motor preparation. Evoked dynamics revealed marked increases in inhibitory circuits in the IFG and M1 with DBS ON. Finally, inhibitory conditioning effects of STN single pulses on corticomotor activity were found at timings relevant for the activation of inhibitory GABAergic receptors (4 and 20 ms). Conclusion: Taken together, these results suggest a predominant role of some markers in explaining beneficial DBS effects, such as a context-dependent modulation of corticospinal excitability and the recruitment of distinct inhibitory circuits, involving long-range projections from higher level motor centers and local GABAergic neuronal populations. These combined measures might help to identify discriminative features of DBS mechanisms towards deep clinical phenotyping of DBS effects in Parkinson's Disease and in other pathological conditions.

Proteomes of Extracellular Vesicles From Pancreatic Cancer Cells and Cancer-Associated Fibroblasts.

OBJECTIVES: Extracellular vesicles (EVs) are lipid bound vesicles secreted by cells into the extracellular environment. Studies have implicated EVs in cell proliferation, epithelial-mesenchymal transition, metastasis, angiogenesis, and mediating the interaction of tumor cells and microenvironment. A systematic characterization of EVs from pancreatic cancer cells and cancer-associated fibroblasts (CAFs) would be valuable for studying the roles of EV proteins in pancreatic tumorigenesis. METHODS: Proteomic and functional analyses were applied to characterize the proteomes of EVs released from 5 pancreatic cancer lines, 2 CAF cell lines, and a normal pancreatic epithelial cell line (HPDE). RESULTS: More than 1400 nonredundant proteins were identified in each EV derived from the cell lines. The majority of the proteins identified in the EVs from the cancer cells, CAFs, and HPDE were detected in all 3 groups, highly enriched in the biological processes of vesicle-mediated transport and exocytosis. Protein networks relevant to pancreatic tumorigenesis, including epithelial-mesenchymal transition, complement, and coagulation components, were significantly enriched in the EVs from cancer cells or CAFs. CONCLUSIONS: These findings support the roles of EVs as a potential mediator in transmitting epithelial-mesenchymal transition signals and complement response in the tumor microenvironment and possibly contributing to coagulation defects related to cancer development.

Metabolic targeting of NRF2 potentiates the efficacy of the TRAP1 inhibitor G-TPP through reduction of ROS detoxification in colorectal cancer.

Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a mitochondrial homolog of HSP90 chaperones. It plays an important role in protection against oxidative stress and apoptosis by regulating reactive oxidative species (ROS). To further elucidate the mechanistic role of TRAP1 in regulating tumor cell survival, we used gamitrinib-triphenylphosphonium (G-TPP) to inhibit TRAP1 signaling pathways in colon cancer. Inhibition of TRAP1 by G-TPP disrupted redox homeostasis and induced cell death. However, colon cancers show a wide range of responses to G-TPP treatment through the induction of variable ER stress responses and ROS accumulation. Interestingly, a strong inverse correlation was observed between the expression of TRAP1 and antioxidant genes in colon tumor tissues using the GSE106582 database. Using a luciferase reporter assay, we detected increased transcriptional activation of antioxidant response elements (AREs) in G-TPP-treated DLD1 and RKO cells but not in SW48 cells. We found that G-TPP induced upregulation of GRP78, CHOP and PARP cleavage in G-TPP-sensitive cells (SW48). In contrast, G-TPP treatment of G-TPP-resistant cells (DLD1 and RKO) resulted in excessive activation of the antioxidant gene NRF2, leading to ROS detoxification and improved cell survival. The NRF2 target genes HO1 and NQO1 were upregulated in G-TPP-treated DLD1 cells, making the cells more resistant to G-TPP treatment. Furthermore, treatment with both a NRF2 inhibitor and a TRAP1 inhibitor led to excessive ROS production and exacerbated G-TPP-induced cell death in G-TPP-resistant cells. Taken together, dual targeting of TRAP1 and NRF2 may potentially overcome colon cancer resistance by raising cellular ROS levels above the cytotoxic threshold.

X-aptamers targeting Thy-1 membrane glycoprotein in pancreatic ductal adenocarcinoma.

Modified DNA aptamers incorporated with amino-acid like side chains or drug-like ligands can offer unique advantages and enhance specificity as affinity ligands. Thy-1 membrane glycoprotein (THY1 or CD90) was previously identified as a biomarker candidate of neovasculature in pancreatic ductal adenocarcinoma (PDAC). The current study developed and evaluated modified DNA X-aptamers targeting THY1 in PDAC. The expression and glycosylation of THY1 in PDAC tumor tissues were assessed using immunohistochemistry and quantitative proteomics. Bead-based X-aptamer library that contains 108 different sequences was used to screen for high affinity THY1 X-aptamers. The sequences of the X-aptamers were analyzed with the next-generation sequencing. The affinities of the selected X-aptamers to THY1 were quantitatively evaluated with flow cytometry. Three high affinity THY1 X-aptamers, including XA-B217, XA-B216 and XA-A9, were selected after library screening and affinity binding evaluation. These three X-aptamers demonstrated a high binding affinity and specificity to THY1 protein and the THY1 expressing cell lines, using THY1 antibody as a comparison. The development of these X-aptamers provides highly specific and non-immunogenic affinity ligands for THY1 binding in the context of biomarker development and clinical applications. They could be further exploited to assist molecular imaging of PDAC targeting THY1.

Systemic Proteome Alterations Linked to Early Stage Pancreatic Cancer in Diabetic Patients.

BACKGROUND: Diabetes is a risk factor associated with pancreatic ductal adenocarcinoma (PDAC), and new adult-onset diabetes can be an early sign of pancreatic malignancy. Development of blood-based biomarkers to identify diabetic patients who warrant imaging tests for cancer detection may represent a realistic approach to facilitate earlier diagnosis of PDAC in a risk population. METHODS: A spectral library-based proteomic platform was applied to interrogate biomarker candidates in plasma samples from clinically well-defined diabetic cohorts with and without PDAC. Random forest algorithm was used for prediction model building and receiver operating characteristic (ROC) curve analysis was applied to evaluate the prediction probability of potential biomarker panels. RESULTS: Several biomarker panels were cross-validated in the context of detection of PDAC within a diabetic background. In combination with carbohydrate antigen 19-9 (CA19-9), the panel, which consisted of apolipoprotein A-IV (APOA4), monocyte differentiation antigen CD14 (CD14), tetranectin (CLEC3B), gelsolin (GSN), histidine-rich glycoprotein (HRG), inter-alpha-trypsin inhibitor heavy chain H3 (ITIH3), plasma kallikrein (KLKB1), leucine-rich alpha-2-glycoprotein (LRG1), pigment epithelium-derived factor (SERPINF1), plasma protease C1 inhibitor (SERPING1), and metalloproteinase inhibitor 1 (TIMP1), demonstrated an area under curve (AUC) of 0.85 and a two-fold increase in detection accuracy compared to CA19-9 alone. The study further evaluated the correlations of protein candidates and their influences on the performance of biomarker panels. CONCLUSIONS: Proteomics-based multiplex biomarker panels improved the detection accuracy for diagnosis of early stage PDAC in diabetic patients.

Gut Microbial Protein Expression in Response to Dietary Patterns in a Controlled Feeding Study: A Metaproteomic Approach.

Although the gut microbiome has been associated with dietary patterns linked to health, microbial metabolism is not well characterized. This ancillary study was a proof of principle analysis for a novel application of metaproteomics to study microbial protein expression in a controlled dietary intervention. We measured the response of the microbiome to diet in a randomized crossover dietary intervention of a whole-grain, low glycemic load diet (WG) and a refined-grain, high glycemic load diet (RG). Total proteins in stools from 9 participants at the end of each diet period (n = 18) were analyzed by LC MS/MS and proteins were identified using the Human Microbiome Project (HMP) human gut microbiome database and UniProt human protein databases. T-tests, controlling for false discovery rate (FDR) <10%, were used to compare the Gene Ontology (GO) biological processes and bacterial enzymes between the two interventions. Using shotgun proteomics, more than 53,000 unique peptides were identified including microbial (89%) and human peptides (11%). Forty-eight bacterial enzymes were statistically different between the diets, including those implicated in SCFA production and degradation of fatty acids. Enzymes associated with degradation of human mucin were significantly enriched in the RG diet. These results illustrate that the metaproteomic approach is a valuable tool to study the microbial metabolism of diets that may influence host health.

Metaproteomics Study of the Gut Microbiome.

Proteomics is a widely used method for defining the protein composition of a complex sample. As this approach allows for identification and quantification of proteins across a broad dynamic range as well as detection of post-translational modifications, proteomics is an ideal platform to investigate the gut microbiome at a functional level. The gut microbiome is a dynamic environment which is crucial for overall health and fitness. Imbalances in the gut microbiome can influence nutrient absorption, pathogen resistance, inflammation, and various human diseases. Metaproteomic analysis of the gut microbiome is currently being performed on bacteria isolated from (1) fecal samples (2) colonic lavage, or (3) colon biopsies. Investigation of the gut microbiome has demonstrated that within the colon, there are distinct communities based on spatial location, and separable from the gut microbiomes isolated from stool. In addition to expanding our understanding of host-bacterial interactions for human health and disease, gut microbiome analysis is being utilized for biomarker development to discriminate normal individuals and diseased (i.e., inflammatory bowel disease or colon cancer) patients as well as to monitor disease activity and prognosis.

Avian Intestinal Mucus Modulates Campylobacter jejuni Gene Expression in a Host-Specific Manner.

Campylobacter jejuni is a leading cause of bacterial foodborne illness in humans worldwide. However, C. jejuni naturally colonizes poultry without causing pathology where it resides deep within mucus of the cecal crypts. Mucus may modulate the pathogenicity of C. jejuni in a species-specific manner, where it is pathogenic in humans and asymptomatic in poultry. Little is known about how intestinal mucus from different host species affects C. jejuni gene expression. In this study we characterized the growth and transcriptome of C. jejuni NCTC11168 cultured in defined media supplemented with or without mucus isolated from avian (chicken or turkey) or mammalian (cow, pig, or sheep) sources. C. jejuni showed substantially improved growth over defined media, with mucus from all species, showing that intestinal mucus was an energy source for C. jejuni. Seventy-three genes were differentially expressed when C. jejuni was cultured in avian vs. mammalian mucus. Genes associated with iron acquisition and resistance to oxidative stress were significantly increased in avian mucus. Many of the differentially expressed genes were flanked by differentially expressed antisense RNA asRNA, suggesting a role in gene regulation. This study highlights the interactions between C. jejuni and host mucus and the impact on gene expression, growth and invasion of host cells, suggesting important responses to environmental cues that facilitate intestinal colonization. IMPORTANCE  Campylobacter jejuni infection of humans is an important health problem world-wide and is the leading bacterial cause of foodborne illnesses in U.S. The main route for exposure for humans is consumption of poultry meat contaminated during processing. C. jejuni is frequently found in poultry, residing within the mucus of the intestinal tract without causing disease. It is not clear why C. jejuni causes disease in some animals and humans, while leaving birds without symptoms. To understand its activity in birds, we characterized C. jejuni responses to poultry mucus to identify genes turned on in the intestinal tract of birds. We identified genes important for colonization and persistence within the poultry gut, turned on when C. jejuni was exposed to poultry mucus. Our findings are an important step in understanding how C. jejuni responds and interacts in the poultry gut, and may identify ways to reduce C. jejuni in birds.

Disrupting glutamine metabolic pathways to sensitize gemcitabine-resistant pancreatic cancer.

Pancreatic cancer is a lethal disease with poor prognosis. Gemcitabine has been the first line systemic treatment for pancreatic cancer. However, the rapid development of drug resistance has been a major hurdle in gemcitabine therapy leading to unsatisfactory patient outcomes. With the recent renewed understanding of glutamine metabolism involvement in drug resistance and immuno-response, we investigated the anti-tumor effect of a glutamine analog (6-diazo-5-oxo-L-norleucine) as an adjuvant treatment to sensitize chemoresistant pancreatic cancer cells. We demonstrate that disruption of glutamine metabolic pathways improves the efficacy of gemcitabine treatment. Such a disruption induces a cascade of events which impacts glycan biosynthesis through Hexosamine Biosynthesis Pathway (HBP), as well as cellular redox homeostasis, resulting in global changes in protein glycosylation, expression and functional effects. The proteome alterations induced in the resistant cancer cells and the secreted exosomes are intricately associated with the reduction in cell proliferation and the enhancement of cancer cell chemosensitivity. Proteins associated with EGFR signaling, including downstream AKT-mTOR pathways, MAPK pathway, as well as redox enzymes were downregulated in response to disruption of glutamine metabolic pathways.

Biomarkers for colitis-associated colorectal cancer.

Patients with extensive ulcerative colitis (UC) of more than eight years duration have an increased risk of colorectal cancer. Molecular biomarkers for dysplasia and cancer could have a great clinical value in managing cancer risk in these UC patients. Using a wide range of molecular techniques - including cutting-edge OMICS technologies - recent studies have identified clinically relevant biomarker candidates from a variety of biosamples, including colonic biopsies, blood, stool, and urine. While the challenge remains to validate these candidate biomarkers in multi-center studies and with larger patient cohorts, it is certain that accurate biomarkers of colitis-associated neoplasia would improve clinical management of neoplastic risk in UC patients. This review highlights the ongoing avenues of research in biomarker development for colitis-associated colorectal cancer.

Implementing the Prospective Surveillance Model (PSM) of Rehabilitation for Breast Cancer Patients with 1-Year Postoperative Follow-up, a Prospective, Observational Study.

BACKGROUND: The Prospective Surveillance Model (PSM) of rehabilitation for patients with breast cancer aims for early identification, treatment, and support of physical impairments postoperatively. The purpose of this study was to describe the incidence of impairments during the first postoperative year and the differences between the patients requiring rehabilitation intervention versus those not requiring intervention. METHODS: A total of 120 patients were enrolled. Impairment measures included: pain, range of motion, and self-reported measures of function using the Upper Extremity Functional Index (UEFI) and Quick Disability of the Arm, Shoulder and Hand (QuickDASH) questionnaires. These measures were performed at designated intervals during the first postoperative year. All patients received exercise and education, and patients with identified impairments underwent individualized rehabilitation intervention. Clinical factors associated with need for intervention were determined using univariate analysis. RESULTS: Thirty-six patients required rehabilitation intervention. There were no statistically significant differences between intervention and no-intervention groups for body mass index, breast surgery type, reconstruction type, or radiotherapy. Statistically significant differences were found between intervention and no-intervention groups in early postoperative UEFI, QuickDASH, pain scores, age, number of lymph nodes removed [9.3 (intervention) vs. 5.6 (no-intervention)], axillary surgery type, chemotherapy, and breast cancer stage. CONCLUSIONS: Survivorship practitioners should have heightened awareness for rehabilitation intervention in patients with greater axillary surgery and burden of disease. Patients with more activity restriction and lower levels of function in the early postoperative period may benefit from rehabilitation intervention. Future studies should focus on implementing a screening tool to identify patients in need of rehabilitation referral.

Proteins associated with pancreatic cancer survival in patients with resectable pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease with a dismal prognosis. However, while most patients die within the first year of diagnosis, very rarely, a few patients can survive for >10 years. Better understanding the molecular characteristics of the pancreatic adenocarcinomas from these very-long-term survivors (VLTS) may provide clues for personalized medicine and improve current pancreatic cancer treatment. To extend our previous investigation, we examined the proteomes of individual pancreas tumor tissues from a group of VLTS patients (survival ≥10 years) and short-term survival patients (STS, survival <14 months). With a given analytical sensitivity, the protein profile of each pancreatic tumor tissue was compared to reveal the proteome alterations that may be associated with pancreatic cancer survival. Pathway analysis of the differential proteins identified suggested that MYC, IGF1R and p53 were the top three upstream regulators for the STS-associated proteins, and VEGFA, APOE and TGFß-1 were the top three upstream regulators for the VLTS-associated proteins. Immunohistochemistry analysis using an independent cohort of 145 PDAC confirmed that the higher abundance of ribosomal protein S8 (RPS8) and prolargin (PRELP) were correlated with STS and VLTS, respectively. Multivariate Cox analysis indicated that 'High-RPS8 and Low-PRELP' was significantly associated with shorter survival time (HR=2.69, 95% CI 1.46-4.92, P=0.001). In addition, galectin-1, a previously identified protein with its abundance aversely associated with pancreatic cancer survival, was further evaluated for its significance in cancer-associated fibroblasts. Knockdown of galectin-1 in pancreatic cancer-associated fibroblasts dramatically reduced cell migration and invasion. The results from our study suggested that PRELP, LGALS1 and RPS8 might be significant prognostic factors, and RPS8 and LGALS1 could be potential therapeutic targets to improve pancreatic cancer survival if further validated.

Up-regulation of mitochondrial chaperone TRAP1 in ulcerative colitis associated colorectal cancer.

AIM: To characterize tumor necrosis factor receptor-associated protein 1 (TRAP1) expression in the progression of ulcerative colitis (UC)-associated colorectal cancer. METHODS: Chronic UC is an inflammatory bowel disease that predisposes to colorectal cancer. Immunohistochemical analysis was used to evaluate TRAP1 expression on tissue microarrays containing colonic tissues from 42 UC progressors (patients with cancer or dysplasia) and 38 non-progressors (dysplasia/cancer free patients). Statistical analyses of the TRAP1 immunohistochemistry staining were performed using GraphPad Prism. Differences in the TRAP1 level between non-progressors and progressors were tested for statistical significance using the Mann-Whitney test. Receiver operating characteristic curve method was used to quantify marker performance in distinguishing diseased cases from controls. RESULTS: TRAP1 was up-regulated in the colon tissues from UC progressors, but not in the colon tissues from UC non-progressors. Moreover, up-regulation of TRAP1 preceded the neoplastic changes: it was present in both the dysplastic and non-dysplastic tissues of UC progressors. When TRAP1 staining in rectal tissue was used as a diagnostic marker, it could distinguish progressors from non-progressors with 59% sensitivity and 80% specificity. Our study further showed that the increase of TRAP1 expression positively correlated with the degree of inflammation in the colorectal cancer tissues, which could be related to the increased oxidation present in the colonic mucosa from UC progressors. We then investigated the cellular proteome changes underlying oxidative stress, and found that oxidative stress could induce up-regulation of TRAP1 along with several other negative modulators of apoptosis. CONCLUSION: These results suggest that oxidative stress in long standing UC could lead to the increase of cytoprotective protein TRAP1, which in turn could promote cancer progression by preventing or protecting the oxidative damaged epithelial cells from undergoing apoptosis. TRAP1 could be a potential diagnostic marker for UC associated colorectal cancer.

Quantitative glycoproteomics analysis reveals changes in N-glycosylation level associated with pancreatic ductal adenocarcinoma.

Glycosylation plays an important role in epithelial cancers, including pancreatic ductal adenocarcinoma. However, little is known about the glycoproteome of the human pancreas or its alterations associated with pancreatic tumorigenesis. Using quantitative glycoproteomics approach, we investigated protein N-glycosylation in pancreatic tumor tissue in comparison with normal pancreas and chronic pancreatitis tissue. The study lead to the discovery of a roster of glycoproteins with aberrant N-glycosylation level associated with pancreatic cancer, including mucin-5AC (MUC5AC), carcinoembryonic antigen-related cell adhesion molecule 5 (CEACAM5), insulin-like growth factor binding protein (IGFBP3), and galectin-3-binding protein (LGALS3BP). Pathway analysis of cancer-associated aberrant glycoproteins revealed an emerging phenomenon that increased activity of N-glycosylation was implicated in several pancreatic cancer pathways, including TGF-ß, TNF, NF-kappa-B, and TFEB-related lysosomal changes. In addition, the study provided evidence that specific N-glycosylation sites within certain individual proteins can have significantly altered glycosylation occupancy in pancreatic cancer, reflecting the complexity of the molecular mechanisms underlying cancer-associated glycosylation events.

Transcriptional reprogramming and stimulation of leaf respiration by elevated CO2 concentration is diminished, but not eliminated, under limiting nitrogen supply.

Plant respiration responses to elevated CO2 concentration ( [CO2 ] ) have been studied for three decades without consensus about the mechanism of response. Positive effects of elevated [CO2 ] on leaf respiration have been attributed to greater substrate supply resulting from stimulated photosynthesis. Negative effects of elevated [CO2 ] on leaf respiration have been attributed to reduced demand for energy for protein turnover assumed to result from lower leaf N content. Arabidopsis thaliana was grown in ambient (370 ppm) and elevated (750 ppm) [CO2 ] with limiting and ample N availabilities. The stimulation of leaf dark respiration was attenuated in limiting N (+12%) compared with ample N supply (+30%). This response was associated with smaller stimulation of photosynthetic CO2 uptake, but not interactive effects of elevated CO2 and N supply on leaf protein, amino acids or specific leaf area. Elevated [CO2 ] also resulted in greater abundance of transcripts for many components of the respiratory pathway. A greater transcriptional response to elevated [CO2 ] was observed in ample N supply at midday versus midnight, consistent with reports that protein synthesis is greatest during the day. Greater foliar expression of respiratory genes under elevated [CO2 ] has now been observed in diverse herbaceous species, suggesting a widely conserved response.

Clonal expansions and short telomeres are associated with neoplasia in early-onset, but not late-onset, ulcerative colitis.

BACKGROUND: Patients with ulcerative colitis (UC) are at risk of developing colorectal cancer. We have previously reported that cancer progression is associated with the presence of clonal expansions and shorter telomeres in nondysplastic mucosa. We sought to validate these findings in an independent case-control study. METHODS: This study included 33 patients with UC: 14 progressors (patients with high-grade dysplasia or cancer) and 19 nonprogressors. For each patient, a mean of 5 nondysplastic biopsies from proximal, mid, and distal colon were assessed for clonal expansions, as determined by clonal length altering mutations in polyguanine tracts, and telomere length, as measured by quantitative PCR. Both parameters were compared with individual clinicopathological characteristics. RESULTS: Clonal expansions and shorter telomeres were more frequent in nondysplastic biopsies from UC progressors than nonprogressors, but only for patients with early-onset of UC (diagnosis at younger than 50 years of age). Late-onset progressor patients had very few or no clonal expansions and longer telomeres. A few nonprogressors exhibited clonal expansions, which were associated with older age and shorter telomeres. In progressors, clonal expansions were associated with proximity to dysplasia. The mean percentage of clonally expanded mutations distinguished early-onset progressors from nonprogressors with 100% sensitivity and 80% specificity. CONCLUSIONS: Early-onset progressors develop cancer in a field of clonally expanded epithelium with shorter telomeres. The detection of these clones in a few random nondysplastic colon biopsies is a promising cancer biomarker in early-onset UC. Curiously, patients with late-onset UC seem to develop cancer without the involvement of such fields.

Pan-colonic field defects are detected by CGH in the colons of UC patients with dysplasia/cancer.

BAC arrays were used to evaluate genomic instability along the colon of patients with ulcerative colitis (UC). Genomic instability increases with disease progression and biopsies more proximal to dysplasia showed increased instability. Pan-colonic field copy number gain or loss involving small (<1Mb) regions were detected in most patients and were particularly apparent in the UC progressor patients who had dysplasia or cancer. Chromosomal copy gains or losses affecting large regions were mainly restricted to dysplastic biopsies. Areas of significant chromosomal losses were detected in the UC progressors on chromosomes 2q36, 3q25, 3p21, 4q34, 4p16.2, 15q22, and 16p13 (p-value⩽0.04). These results extend our understanding of the dynamic nature of pan-colonic genomic instability in this disease.