Infliximab in ulcerative colitis: real-life analysis of factors predicting treatment discontinuation due to lack of response or colectomy: ECIA (ACAD Colitis and Infliximab Study).

OBJECTIVE: To describe clinical practice with infliximab (IFX) in ulcerative colitis (UC); identification of predictive factors for IFX treatment discontinuation due to insufficient response and for colectomy. MATERIAL AND METHODS: Retrospective, multicentric and observational study including every UC IFX-treated patient in 10 Spanish hospitals. Variables analyzed: epidemiological data; variables for poor prognosis; IFX prior treatments; characteristics of the IFX treatment; time from the UC diagnosis to induction with IFX; time from induction to colectomy or until data collection. Predictive and protective factors for IFX discontinuation due to lack of response and for colectomy were analyzed with binary logistic regression and Cox analysis. RESULTS: Follow-up time from induction with IFX to the collection of data or colectomy: 36.7 ± 25.7 months. Prior treatment with immunomodulator medications (IMM): 79%; IFX + immunosuppressant therapy: 77%; discontinuation of IFX: 26%, colectomy 16%. Independent predictive or protective factors for IFX discontinuation: IMM resistance (OR: 2.9, p = 0.022, 95% CI: 1.2-7.2), prior use of leukocytapheresis (OR: 3.3, p = 0.024, 95% CI: 1.1-9.4), IFX + IMM therapy (OR: 0.3, p = 0.022, 95% CI: 0.1-0.9, and HR: 0.4, p = 0.006, 95% CI: 0.2-0.8) and corticosteroid use in induction (HR: 1.9, p = 0.049, 95% CI: 1.0-3.8). Independent predictive or protective factors for colectomy: Use of leukocytapheresis (OR: 3.0, p = 0.036, 95% CI: 1.1-8.4), IFX + IMM therapy (OR: 0.3, p = 0.022, 95% CI: 0.1-0.8, and HR: 0.3, p = 0.011, 95% CI: 0.1-0.8) and severe cortico-resistant flare-up (HR: 2.5, p = 0.032, 95% CI: 1.1-5.9). CONCLUSIONS: Prior use of IMM and leukocytapheresis, the use of corticosteroids in induction and a severe cortico-resistant flare predict a worse response to IFX and the need for colectomy. Combination therapy is a protective factor for both.

Frequency, predictors, and consequences of maintenance infliximab therapy intensification in ulcerative colitis.

INTRODUCTION: Infliximab (IFX) therapy intensification in ulcerative colitis (UC) is more common than established in pivotal studies. OBJECTIVES: To establish the frequency and form of intensification for UC in clinical practice, as well as predictors, and to compare outcomes between intensified and non-intensified treatment. METHODS: A retrospective study of 10 hospitals and 144 patients with response to infliximab (IFX) induction. Predictive variables for intensification were analyzed using a Cox regression analysis. Outcome, loss of response to IFX, and colectomy were compared between intensified and non-intensified therapy. RESULTS: Follow-up time from induction to data collection: 38 months [interquartile range (IQR), 20-62]. Time on IFX therapy: 24 months (IQR, 10-44). In all, 37% of patients required intensification. Interval was shortened for 36 patients, dose was increased for 7, and 10 subjects received both. Concurrent thiopurine immunosuppressants (IMM) and IFX initiation was an independent predictor of intensification [Hazard ratio, 0.034; p, 0.006; CI, 0.003-0.371]. In patients on intensified therapy IFX discontinuation for loss of response (30.4% vs. 10.2%; p, 0.002), steroid reintroduction (35% vs. 18%; p, 0.018), and colectomy (22% vs. 6.4%; p, 0.011) were more common. Of patients on intensification, 17% returned to receiving 5 mg/kg every 8 weeks. CONCLUSIONS: Intensification is common and occasionally reversible. IMM initiation at the time of induction with IFX predictsnon-intensification. Intensification, while effective, is associated with poorer outcome.

Cancer-associated fibroblast and M2 macrophage markers together predict outcome in colorectal cancer patients.

Tumor epithelial cells within a tumor coexist with a complex microenvironment in which a variety of interactions between its various components determine the behavior of the primary tumors. Cancer-associated fibroblasts (CAF) and M2 macrophages, characterized by high expression of different markers, including α-SMA, FSP1 and FAP, or CD163 and DCSIGN, respectively, are involved in the malignancy of different tumors. In the present study, expression of the above markers in CAF and M2 macrophages was analyzed using RT-PCR and immunohistochemistry in the normal mucosa and tumor tissue from a cohort of 289 colorectal cancer patients. Expression of CAF and M2 markers is associated with the clinical outcome of colorectal cancer patients. Moreover, the combination of CAF and M2 markers identifies three groups of patients with clear differences in the progression of the disease. This combined variable could be a decisive factor in the survival of advanced-stage patients. Taken together, these analyses demonstrate the prognostic involvement of interrelationships between DCSIGN, CD163, α-SMA, FSP1 and FAP markers in the survival of colon cancer patients.

Assessment of obesity stigma and discrimination among Spanish subjects with a wide weight range: the OBESTIGMA study.

Introduction: This study aims to assess the extent of rejection and instances of stigmatization linked to obesity within the Spanish population, encompassing a diverse spectrum of weights ranging from normal weight to morbid obesity. Additionally, the study seeks to identify the primary factors influencing these experiences and further examines the impact of bariatric surgery on such dynamics. Materials and methods: Multicenter observational study with involving a total of 1,018 participants who were recruited from various Obesity Units. Negatives attitudes towards people with obesity were assessed through three questionnaires: (i) Antifat Attitudes Scale (AFA), (ii) Stigmatizing Situations Inventory (SSI) and (iii) Weight Bias Internalization Scale (WBIS). Subjects were categorized into four groups based on their BMI and history of prior bariatric surgery. Results: The cumulative score across all questionnaires (AFA, SSI and WBIS) exhibited a progressive increase, from participants with normal weight to those with obesity (p < 0.001 for all). Within the AFA questionnaire, males showed more rejection towards people with obesity than women, also perceiving obesity as a disease linked to a lack of willpower (p = 0.004 and p = 0.030, respectively). The overall SSI score was negatively associated with age (r = -0.080, p = 0.011), with young participants encountering more stigmatizing experiences than their adult counterparts. Neither employment status nor educational demonstrated a significant association with any of the questionnaires. Interestingly, patients who underwent lost weight following bariatric surgery did not exhibit improved outcomes. Conclusion: Individuals with obesity demonstrate a heightened level of aversion towards the disease compared to those with normal weight. Concurrently, the incidence of stigmatizing encounters displays a concerning escalation among younger individuals.

Cardiovascular risk in subjects over 55 years of age and cognitive performance after five years. NEDICES2-RISK study. Study protocol.

BACKGROUND: Cognitive impairment and dementia have a high prevalence among the elderly and cause significant socio-economic impact. Any progress in their prevention can benefit millions of people. Current data indicate that cardiovascular risk (CVR) factors increase the risk of developing cognitive impairment and dementia. Using models to calculate CVR specific for the Spanish population can be useful for estimating the risk of cognitive deterioration since research on this topic is limited and predicting this risk is mainly based on outcomes in the Anglo-Saxon population. The aim of this study is to assess the relationship between CVR in the Spanish population, as calculated using the FRESCO (Función de Riesgo Española de acontecimientos Coronarios y Otros) and REGICOR (Registre Gironí del Cor) CVR tables, and the change in cognitive performance at a 5-year follow-up. METHODS: Design: Observational, analytic, prospective cohort study, with a 5-year follow-up. Ambit: Population. Population: Subjects 55 to 74 years of age, included in the NEDICES2 (2014-2017) cohort, who did not present dementia and had undergone the neuropsychological evaluation (N = 962). Variables: Exposure factors (CVR factors and estimated risk according to the CVR predictors by REGICOR and FRESCO), dependent variables (change in the score of the brief neuropsychological test in the study NEDICES2 five years after the first evaluation), and clinical and socio-demographic variables. Statistical analysis: Analysis of data quality. Descriptive analysis: socio-demographic and clinical variables of subjects. Bivariate analysis: relationship between basal CVR and change in neuropsychological tests. Multivariate analysis: relationship between basal CVR and change in neuropsychological tests adjusted by co-variables. Analysis and comparison of the reliable change in independent samples. DISCUSSION: The Spanish population can benefit from determining if individuals with high CVR, which is commonly detected in usual clinical practice, will present decreased cognitive performance compared to subjects with lower CVR. This study can affect how to address CVR factors and the design of effective prevention strategies for cognitive deterioration. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03925844.

Molecular diagnosis of polycystic ovary syndrome in obese and non-obese women by targeted plasma miRNA profiling.

OBJECTIVE: Polycystic ovary syndrome (PCOS) is diagnosed based on the clinical signs, but its presentation is heterogeneous and potentially confounded by concurrent conditions, such as obesity and insulin resistance. miRNA have recently emerged as putative pathophysiological and diagnostic factors in PCOS. However, no reliable miRNA-based method for molecular diagnosis of PCOS has been reported. The aim of this study was to develop a tool for accurate diagnosis of PCOS by targeted miRNA profiling of plasma samples, defined on the basis of unbiased biomarker-finding analyses and biostatistical tools. METHODS: A case-control PCOS cohort was cross-sectionally studied, including 170 women classified into four groups: non-PCOS/lean, non-PCOS/obese, PCOS/lean, and PCOS/obese women. High-throughput miRNA analyses were performed in plasma, using NanoString technology and a 800 human miRNA panel, followed by targeted quantitative real-timePCR validation. Statistics were applied to define optimal normalization methods, identify deregulated biomarker miRNAs, and build classification algorithms, considering PCOS and obesity as major categories. RESULTS: The geometric mean of circulating hsa-miR-103a-3p, hsa-miR-125a-5p, and hsa-miR-1976, selected among 125 unchanged miRNAs, was defined as optimal reference for internal normalization (named mR3-method). Ten miRNAs were identified and validated after mR3-normalization as differentially expressed across the groups. Multinomial least absolute shrinkage and selection operator regression and decision-tree models were built to reliably discriminate PCOS vs non-PCOS, either in obese or non-obese women, using subsets of these miRNAs as performers. CONCLUSIONS: We define herein a robust method for molecular classification of PCOS based on unbiased identification of miRNA biomarkers and decision-tree protocols. This method allows not only reliable diagnosis of non-obese women with PCOS but also discrimination between PCOS and obesity. CAPSULE: We define a novel protocol, based on plasma miRNA profiling, for molecular diagnosis of PCOS. This tool not only allows proper discrimination of the condition in non-obese women but also permits distinction between PCOS and obesity, which often display overlapping clinical presentations.

Effectiveness of an intervention in groups of family caregivers of dependent patients for their application in primary health centers. Study protocol.

BACKGROUND: Although Primary Health Care (PHC) Teams are used to deal with prevention and treatment of sanitary problems in adults with chronic diseases, they usually have a lack of experience in development of psychotherapeutic interventions. However, these interventions are the ones that achieve better results to reduce symptomatology and improve emotional state of caregivers.The study aims to evaluate the effectiveness of an intervention of psychotherapy in improving the mental health and Quality of life of caregivers. This intervention is based on theoretical approaches to care adjusted to cognitive theory, in order to be applied in primary health care centres. METHODS/DESIGN: This is multicentre clinical trials study, randomized in two parallel groups, carry out in two PHC, Study population: 150 caregivers will be included by consecutive sampling and they will be randomized the half to experimental group and the other half to control group. They provide mostly all the assistance to care-dependent familiars receiving attention in PHC Centers. MEASUREMENTS: Each caregiver will be evaluated on a personal interview. The caregivers' assessment protocol: 1) Assessment of different socio-demographic related to care, and caregiver's personal situation. 2)Care-dependent individuals will also be assessed by Barthel Index and Pfeiffer Questionnaire (SPMSQ). 3)Change in caregivers will be the principal measure: family function (Family APGAR Questionnaire), burden short questionnaire (Short Zarit Burden Interview), quality of life (Ruiz & Baca: 1993 Questionnaire), the Duke-UNK Functional Social Support Questionnaire, the General Health Questionnaire-12, and changes in Dysfunctional Thoughts about caring. 4) Intervention implementation measures will also be assessed. INTERVENTION: A psychotherapeutic intervention will be 8 sessions of 90 minutes in groups. This intervention has been initially developed for family caregivers of patients with dementia. DISCUSSION: Psychotherapeutic interventions have been proved to obtain better results to reduce symptomatology and improve emotional state of caregivers. Moreover, this intervention has been proved to be effective in a different setting other than PHC, and was developed by professionals of Mental Health. If we found that this intervention is effective in PHC and with our professionals, it would be an important instrument to offer to caregivers of care-dependent patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier NCT01177696.

Deregulated expression of miR-106a predicts survival in human colon cancer patients.

MicroRNAs (miRNAs) are noncoding RNAs that regulate expression of target mRNAs and are controlled by tumor suppressors and oncogenes. Altered expression of specific miRNAs in several tumor types and its association with poor prognosis parameters have been reported. Fewer data are available on its impact on patients' survival. We studied the impact of the expression of miR-17-5p, miR-106a, and miR-126 on survival and its correlation with the levels of their target mRNAs and host gene and TP53 alterations. We assessed in 110 colon cancer patients the levels of miR-17-5p, miR-106a, miR-126, E2F1, and EGFL7 by quantitative real-time RT-PCR and loss of heterozygosity (LOH) in the TP53 region. Tumor characteristics, disease-free survival (DFS), and overall survival (OS) were examined in each patient. Altered expression of miR-17-5p, miR-106a, and EGFL7 was associated with pathological tumor features of poor prognosis. Downregulation of miR-106a predicted shortened DFS (P = 0.03) and OS (P = 0.04). miR-17-5p correlated with DFS only at early stages (P = 0.07). Inverse correlations were found between miR-17-5p and miR-106a levels and their target expression, E2F1 (P = 0.04 and P = 0.03, respectively). No correlation was found between miR-126 expression and its host gene levels, EGFL7. miR-106a deregulation was revealed as a marker of DFS and OS independent of tumor stage. The lack of association between expression of miR-126 and its host gene EGFL7 suggests their regulation by independent stimuli. Inverse correlation between miR-17-5p and miR-106a and E2F1 levels supports E2F1 as a target mRNA for the two miRNAs.

Prognostic value of LISCH7 mRNA in plasma and tumor of colon cancer patients.

PURPOSE: LISCH7 is a gene potentially regulated by p53 that is up-regulated in metastasis development. Our hypothesis was that the expression of LISCH7 in primary colorectal tumors determined certain characteristics of the tumors, as well as their behavior, and that its identification in plasma could serve as a prognostic marker. EXPERIMENTAL DESIGN: We tested this hypothesis in a series of 115 tumors and normal tissues and in 83 plasmas from patients with sporadic colorectal carcinomas, as well as in 20 healthy control plasmas in which the expression levels of the gene were measured by real-time PCR. The expression data were contrasted with clinicopathologic variables. RESULTS: Although LISCH7 expression was not detected in any control plasma samples, it was positive in 25 (30.1%) plasmas from patients (P = 0.002). LISCH7 mRNA in plasma was significantly associated with the pathologic stage (P = 0.019), with lymph node metastasis (P = 0.008) and with vascular invasion (P = 0.005). Expression was not detected in any normal tissues but was detected in 80 tumor tissues, with a clear association found with vascular invasion (P = 0.027). Moreover, we show that LISCH7 was specifically expressed by the epithelial tumor cells. The adjusted overall survival study showed independent prognostic values for LISCH7 expression levels in tumor tissues (hazard ratio, 3.45; 95% confidence interval, 1.19-9.98). CONCLUSIONS: Our results suggest that LISCH7 is a good tumor marker whose expression levels could be considered as a poor prognosis factor in human colon cancer. Furthermore, plasma is suggested as a feasible source of nucleic acids for subsequent noninvasive prognostic studies.

[Factors associated with emergency department revisits for acute bacterial prostatitis]. / Factores asociados a la reconsulta en urgencias en la prostatitis aguda bacteriana.

OBJECTIVES: To analyze factors associated with revisits by patients with acute bacterial prostatitis treated in a hospital emergency department. MATERIAL AND METHODS: Descriptive analysis and prospective follow-up of a cohort of patients with acute bacterial prostatitis treated in an emergency department. RESULTS: We included 241 episodes of acute bacterial prostatitis. The mean (SD) age was 63 (16) years. Seventy-three percent reported dysuria, 64% had fever, and between 15.4% and 22.4% had medical histories of cancer, urethral/bladder catheterization, or prostate adenoma. Positive urine cultures were obtained for 48.1% and positive blood cultures for 17.6%. Escherichia coli was the bacterium isolated most often, and 27.7% of the cultures showed resistance to ciprofloxacin and amoxicillin-clavulanic acid. Twenty-nine patients (12%) revisited within 30 days. The only factors associated with revisiting were performance of a rectal examination (odds ratio [OR], 9.23; 95% CI, 1.12-75.82) and bacteremia (OR, 3.81; 95% CI, 1.31-11.04) (P<.05). CONCLUSION: Factors associated with revisiting for acute bacterial prostatitis were bacteremia and performance of a rectal examination.

OBJETIVO: Analizar los factores asociados a la reconsulta del paciente con prostatitis aguda bacteriana (PAB) atendido en el servicio de urgencias hospitalario (SUH). METODO: Estudio analítico de cohorte observacional con seguimiento prospectivo de las PAB atendidas en el SUH durante un año. RESULTADOS: Se registraron 241 episodios de PAB. La edad media fue de 63 (DE: 16) años. Presentaron disuria el 73%, fiebre el 64% y antecedentes de cáncer, manipulación previa de la vía urinaria o adenoma prostático entre el 15,4- 22,4%. El 48,1% de los urocultivos y el 17,6% de los hemocultivos resultaron positivos. Escherichia coli fue el aislamiento mayoritario, presentando con resistencias en el 27,7% a ciprofloxacino y amoxicilina/clavulánico. A los 30 días reconsultaron 29 pacientes (12%). El tacto rectal, con odss ratio (OR) 9,23 (IC 95%: 1,12-75,82), y la bacteriemia, con OR de 3,81 (IC 95%: 1,31-11,04), fueron las únicas variables asociadas a la reconsulta (p <0,05). CONCLUSIONES: Los factores relacionados con la reconsulta del enfermo con PBA fueron la presencia de bacteriemia y el tacto rectal.

Effect of 0.5 mg versus 1 mg varenicline for smoking cessation: a randomized controlled trial.

AIMS: Varenicline is used in smoking cessation. The aims of the trial were to test for differences between standard 1- and 0.5-mg doses (both twice daily during 8 weeks) in (1) abstinence, (2) adherence and (3) side effects. DESIGN: Open-label randomized parallel-group controlled trial with 1-year follow-up. All those randomized were included in the final sample using an intention-to-treat (ITT) approach. SETTING: Stop-Smoking Clinic of the Virgen Macarena University Hospital in Seville, Spain. PARTICIPANTS: The study comprised smokers (n = 484), 59.5% of whom were men with a mean age of 50.67 years and a smoking history of 37.5 pack-years. INTERVENTION AND COMPARATOR: Participants were randomized to 1 mg (n = 245) versus 0.5 mg (n = 239) and received behavioural support, which consisted of a baseline visit and six follow-ups during 1 year. MEASUREMENTS: The primary outcome was continuous self-reported abstinence during 1 year, with biochemical verification. The secondary outcomes were adherence and side effects. Also measured were baseline demographics, medical history and smoking characteristics. FINDINGS: Abstinence rates at 1 year were 46.5% with 1 mg versus 46.4% with 0.5 mg [odds ratio (OR) = 0.997; 95% confidence interval (CI) = 0.7-1.43; P = 1.0]; Bayes factor in favour of H0 = 238.507, Bayes factor against H0 = 0.004. Treatment adherence was similar in both regimens (OR = 1.16; 95% CI = 0.8-1.7; P = 0.44). Side effects were reported in 19.3% of cases with 1 mg versus 12.1% with 0.5 mg, although with no significant differences between regimens (OR = 1.73; 95% CI = 0.94-3.18; P = 0.093). CONCLUSIONS: There appears to be no difference in smoking cessation effectiveness between 1 mg and 0.5 mg varenicline, both administered twice daily for 8 weeks, with similar rates of abstinence (46.5% versus 46.4%), adherence and side effects.

Prevalence of aberrant methylation of p14ARF over p16INK4a in some human primary tumors.

The INK4a/ARF locus encodes two unrelated tumor suppressor proteins, p16INK4a and p14ARF, which participate in the two main cell-cycle control pathways, p16-Rb and p14-p53. Methylation of CpG promoter islands has been described as a mechanism of gene silencing. Exon 1 of the p16INK4a gene and the p14ARF promoter gene reside within CpG islands. Therefore, both can become methylated de novo and silenced. It has recently been proposed that the methylation changes in certain genes could be used as molecular markers for the detection of almost all forms of human cancer. Here, we analyzed concomitantly in each tumor sample and normal tissue the methylation status of p16INK4a and p14ARF by methylation-specific PCR (MSP) in 100 breast, 95 colon and 27 bladder carcinomas. A series of clinicopathological parameter were obtained from the medical records of the patients, p14ARF showed a higher rate of hypermethylation than p16INK4a in all three tumor types. p16INK4a and p14ARF aberrant methylation was significantly correlated with poor prognosis clinicopathological parameters of the three tumor types. We conclude that both p16INKa and p14ARF hypermethylation may be involved in breast, colon and bladder carcinogenesis, with special emphasis on the role of the lesser studied p14ARF gene, and that tumors with aberrant methylation in the two genes were associated with worse prognosis.

Prognostic impact of ΔTAp73 isoform levels and their target genes in colon cancer patients.

PURPOSE: Cumulative data support the role of ΔTAp73 variants in tumorigenic processes such as drug resistance. We evaluate the impact of TP73 isoforms and their putative target genes ABCB1, HMGB1, and CASP1 on the survival of colon cancer patients and the correlation between their expressions. EXPERIMENTAL DESIGN: We determined in 77 colon cancer patients the expression of ΔEx2p73, ΔEx2/3p73, ΔNp73, TAp73, ABCB1, HMGB1, and CASP1 by quantitative real-time reverse transcriptase-PCR. Tumor characteristics, disease-free survival, and overall survival (OS) were examined in each patient. Functional experiments were carried out to check whether ectopic expression of ΔNp73 modifies the proliferation, drug resistance, migration, and invasion properties of colon tumor cells and the expression of ABCB1, HMGB1, and CASP1. RESULTS: Positive correlations were observed between the expression levels of ΔTAp73 variants and HMGB1. Furthermore, a trend was observed for ABCB1. Overexpression of ΔEx2/3p73 and ΔNp73 isoforms was significantly associated with advanced stages (P = 0.04 and P = 0.03, respectively) and predicted shortened OS (P = 0.04 and P = 0.05, respectively). High levels of ABCB1 and HMGB1 were associated with shorter OS (P = 0.04 and P = 0.05, respectively). Multivariate analysis showed that, in addition to the tumor stage, ABCB1 and HMGB1 had independent relationships with OS (P = 0.008). Ectopic expression of ΔNp73 was associated with an increase in proliferation and drug resistance. CONCLUSIONS: The positive correlation between ΔTAp73 variants and HMGB1 and ABCB1 expression supports them as TP73 targets. The fact that upregulation of ΔTAp73 isoforms was associated with shortened OS, increase in proliferation, and drug resistance confirms their oncogenic role and plausible value as prognostic markers. ABCB1 and HMGB1, putative ΔTAp73 target genes, strongly predict OS in an independent manner, making clear the importance of studying downstream TP73 targets that could predict the outcome of colon cancer patients better than ΔTAp73 variants themselves do.

TWIST1 is expressed in colorectal carcinomas and predicts patient survival.

TWIST1 is a transcription factor that belongs to the family of basic helix-loop-helix proteins involved in epithelial-to-mesenchymal transition and invasion processes. The TWIST1 protein possesses oncogenic, drug-resistant, angiogenic and invasive properties, and has been related with several human tumors and other pathologies. Colorectal cancer is one of the tumors in which TWIST1 is over-expressed, but its involvement in the clinical outcome of the disease is still unclear. We tested, by RT-PCR, the expression levels of TWIST1 in normal and tumor paired-sample tissues from a series of 151 colorectal cancer patients, in order to investigate its prognostic value as a tumor marker. TWIST1 expression was restricted to tumor tissues (86.1%) and correlated with lymph node metastasis (LNM). Adjusted analysis showed that the expression levels of TWIST1 correlated with overall survival (OS) and disease-free survival (DFS). Importantly, TWIST1 expression levels predicted OS specifically at stages I and II. Moreover, patients with stage II tumors and high TWIST1 levels showed even shorter survival than patients with stage III tumors. These results suggest that TWIST1 expression levels could be a tumor indicator in stage II patients and help select patients at greater risk of poor prognosis who might benefit from adjuvant chemotherapy.

Intratumoral heterogeneity in microsatellite alterations in BRCA1 and PTEN regions in sporadic colorectal cancer.

BACKGROUND: Chromosome regions 17q21 (BRCA1) and 10q23 (PTEN) have been found deleted in colorectal cancer. METHODS: We studied the frequency of loss of heterozygosity (LOH) in these 2 regions in 214 patients with only 1 sample per tumor and in 100 patients with several samples per tumor. Three microsatellite markers of each region were used for the LOH test. The polymerase chain reaction product was electrophoresed in 8% polyacrylamide gels, and band intensity was shown by silver staining. RESULTS: The proportions of LOH in the two regions were 38.4% for 17q21 and 30.8% for 10q23 in the group of 214 and were 47.7% for 17q21 and 34.7% for 10q23 in the group of 100. We found a high correlation between the LOH in both regions (P <.001), where 81% of LOH in 10q23 region was matched by concomitant LOH in 17q21. In the group of tumors with several samples (group of 100), 39% and 68% did not present LOH in the 17q21 and 10q23 regions, respectively, in all of their tumor samples. However, in the 20 patients with LOH in both regions in the group of 100 (several samples per tumor), all samples with LOH in 10q23 also had LOH in 17q21, whereas not all samples with LOH in 17q21 had LOH in 10q23. CONCLUSIONS: These results show that colorectal cancer is highly heterogeneous, at least for these tumors markers, and suggest a sequential acquisition pattern of these anomalies during tumor growth, in which changes in 17q21 could occur before those in 10q23.