CHK1 expression in Gastric Cancer is modulated by p53 and RB1/E2F1: implications in chemo/radiotherapy response.

Radiation has a limited but relevant role in the adjuvant therapy of gastric cancer (GC) patients. Since Chk1 plays a critical function in cellular response to genotoxic agents, we aimed to analyze the role of Chk1 in GC as a biomarker for radiotherapy resistance. We analyzed Chk1 expression in AGS and MKN45 human GC cell lines by RT-QPCR and WB and in a small cohort of human patient's samples. We demonstrated that Chk1 overexpression specifically increases resistance to radiation in GC cells. Accordingly, abrogation of Chk1 activity with UCN-01 and its expression with shChk1 increased sensitivity to bleomycin and radiation. Furthermore, when we assessed Chk1 expression in human samples, we found a correlation between nuclear Chk1 accumulation and a decrease in progression free survival. Moreover, using a luciferase assay we found that Chk1's expression is controlled by p53 and RB/E2F1 at the transcriptional level. Additionally, we present preliminary data suggesting a posttranscriptional regulation mechanism, involving miR-195 and miR-503, which are inversely correlated with expression of Chk1 in radioresistant cells. In conclusion, Chk1/microRNA axis is involved in resistance to radiation in GC, and suggests Chk1 as a potential tool for optimal stratification of patients susceptible to receive adjuvant radiotherapy after surgery.

Gene expression differences in primary colorectal tumors and matched liver metastases: chemotherapy related or tumoral heterogeneity?

BACKGROUND: Treatment of metastatic colorectal cancer (mCRC) is generally based on genetic testing performed in primary tumor biopsies, but whether the genomic status of primary tumors is identical to that of metastases is not well known. We compared the gene expression profiles of formalin-fixed paraffin-embedded (FFPE) biopsies of colorectal primary tumors and matched liver metastases. PATIENTS AND METHODS: We compared the expression of 18 genes in FFPE CRC tumors and their matched liver metastases from 32 patients. The expression of each gene in CRC primary tumors and their matched liver metastases was tested using Student's t test for paired samples. Pairwise correlations of each gene in the primary tumors and matched liver metastases were evaluated by Pearson's correlation coefficient. RESULTS: The expression of six genes was significantly different in primary tumors compared with their matched liver metastases [CXCR4 (p < 0.001), THBS1 (p = 0.007), MMP 9 (p = 0.048), GST Pi (p = 0.050), TYMP (p = 0.042) and DPYD (p < 0.001)]. For the remaining genes, where no significant differences were observed, only SMAD4 (r s = 0.447, p = 0.010), ERCC1 (r s = 0.423, p = 0.016) and VEGF A (r s = 0.453, p = 0.009) showed significant correlation in expression between the two tissues. Therefore, we only detected similar gene expression levels between the tumor and the metastases in these three markers. CONCLUSIONS: We only found similar gene expression levels between the tumor and the metastases in three genes (SMAD4, ERCC1, and VEGF A). However, our study could not assess whether the differences in gene expression were secondary to tumoral heterogeneity or to molecular changes induced by previous chemotherapy.

SMAD4 and TS expression might predict the risk of recurrence after resection of colorectal liver metastases.

PURPOSE: Colorectal liver metastases (CLM) have significant molecular heterogeneity, which contributes to the risk of recurrence following surgery. Most of the traditional scores intended to predict recurrence is based on clinicopathological variables and it is unclear whether incorporating molecular biomarkers might improve our assessment of the risk of recurrence. Our aim was to determine if molecular biomarkers might be associated with the risk of recurrence after surgery of CLM. PATIENTS AND METHODS: A total of 121 patients diagnosed with colorectal cancer (CRC) with resected liver metastases were included. The role of several clinicopathological variables to predict patient's outcome after resection of liver metastases was analyzed. Eighteen genes related to CRC pathogenesis were also included in the analyses. Univariate and multivariate stepwise Cox regression analyses were performed to identify factors associated with recurrence and the risk of death. RESULTS: Eight prognostic factors for progression-free survival and nine factors for overall survival were identified in the univariate analyses. After adjusting for other risk factors, only the expression of two molecular factors was associated with the risk of recurrence: TS (HR 0.631, 95 % CI 0.422-0.944) and SMAD4 (HR 1.680, 95 % CI 1.047-2.695). None of the variables was significantly associated with the risk of death in the multivariate analyses. CONCLUSIONS: The prognostic significance of most traditional clinicopathological variables might be insufficient to define patients at risk for recurrence after liver metastases resection. Molecular biomarkers might improve the identification of patients with higher risk of recurrence.

MYH polyposis syndrome: clinical findings, genetics issues and management.

Colorectal cancer (CRC) is one of the most frequent cancer in first world. Two hereditary CCR syndrome have been described: familial adenomatous polyposis (FAP) and hereditary non-polyposis colorectal cancer. A recently described biallelic mutation of MYH, is responsible for adenomatous polyposis with an increased risk of CRC and is responsible for 30-40 % of adenomatous polyposis cases in which an APC mutation cannot be found. However, there is no clear consensus in the literature as whether a monoallelic mutation increases the risk for colorectal cancer. In addition, some authors have indicated that the spectrum of extracolonic lesions in MYH associated polyposis (MAP) might be far different from that observed in FAP and could be more similar to Lynch syndrome spectrum. In this review we are going to describe some general and specific aspects of MAP, including genetic topics, clinical features, different phenotypes and strategies to reduce CCR risk.

Pharmacogenetic predictors of severe peripheral neuropathy in colon cancer patients treated with oxaliplatin-based adjuvant chemotherapy: a GEMCAD group study.

BACKGROUND: Oxaliplatin-based chemotherapy (CT), widely used as adjuvant therapy for stage III and selected high-risk stage II colon cancer (CC) patients, is often associated with cumulative peripheral neuropathy. Our aim is to identify single-nucleotide polymorphisms (SNPs) in genes involved in oxaliplatin metabolism, DNA repair mechanisms, cell cycle control, detoxification or excretion pathways to predict severe (grade 2-3) oxaliplatin-induced peripheral neuropathy (OXPN) among CC patients treated with oxaliplatin and fluoropyrimidine-based adjuvant CT. PATIENTS AND METHODS: Genomic DNA was extracted from formalin-fixed-paraffin-embedded peritumoral samples from 206 high-risk stage II and stage III CC patients receiving oxaliplatin-based adjuvant CT from January 2004 to December 2009. Genotyping was carried out for 34 SNPs in 15 genes using MassARRAY (SEQUENOM) technology. A total of 181 stage II-III CC patients treated with the same CT regimens were enrolled as a validation set. RESULTS: The rs2230641 cyclin H (CCNH) rs2230641 C/C [odd ratio (OR)=5.03, 95% confidence interval (CI) 1.061-2.41, P=0.042] and the ATP-binding cassette subfamily G, member 2 (ABCG2) rs3114018 A/A genotypes (OR=2.67; 95% CI 0.95-4.41; P=0.059) were associated with a higher risk of severe OXPN. In addition, patients harboring the combination of CCNH C/C and/or the ABCG2 rs3114018 A/A genotypes had a higher risk of grade 2-3 OXPN than those with the CCNH any T and ABCG2 any C genotypes (37.73% versus 19.42%; OR=2.46; 95% CI 1.19-5.07; P=0.014) in the logistic regression analysis using age, gender, adjuvant CT regimen and cumulative dose of oxaliplatin as covariates. The ability to predict severe OXPN of this combined analysis was independently validated in the second cohort (58% versus 33.33%; OR=2.99; 95% CI 1.45-6.13; P=0.002). CONCLUSIONS: Our results suggest that SNPs in CCNH and ABCG2 can modulate the development of severe OXPN among stage II-III CC patients who received oxaliplatin-based CT, thus enabling the individualization of adjuvant treatment.

Analysis of the concordance in the EGFR pathway status between primary tumors and related metastases of colorectal cancer patients:implications for cancer therapy.

Patients with metastatic Colorectal Cancer (mCRC), in which primary tumors are KRAS mutated, have no response to anti-EGFR therapy. However, less than half of mCRC patients with KRAS wild-type primary tumors respond to anti-EGFR therapy. Other downstream effectors of the EGFR pathway are being analyzed to fine-tune KRAS predictive value. However, as the primary tumor is the tissue of analysis that determines the use of anti-EGFR therapy in advanced disease, a high concordance in the status of these effectors between primary tumors and related metastases is required. We analyzed the concordances of downstream EGFR effectors in tumoral pairs of primaries and related metastases in a series of KRAS wild-type patients. One hundred seventeen tumoral pairs from patients with CRC were tested for KRAS mutational status. The level of concordance in the presence of KRAS mutations was 91% between the primary tumor and related metastases. The 70 pairs with KRAS wild-type primary tumors were further analyzed for BRAF and PIK3CA mutational status and for EGFR, PTEN and pAKT expression, and the number of concordant pairs was 70 (100%), 66 (94%), 43 (61%), 46 (66%) and 36 (54%), respectively. Our findings suggest that the mutational status of KRAS, BRAF and PIK3CA in the primary tumor is an adequate surrogate marker of the status in the metastatic disease. On the other hand, the immunohistochemical analysis of EGFR, PTEN and pAKT showed a much higher degree of discordance between primaries and related metastases.

Chondroitin sulfate improves synovitis in rabbits with chronic antigen-induced arthritis.

OBJECTIVE: Our aim was to explore the effect of chondroitin sulfate (CS), a natural glycosaminoglycan with attributed anti-inflammatory properties, on synovitis in a rabbit model of chronic arthritis with intense systemic inflammation bolstered by endothelial lesion and atherosclerotic diet. METHODS: Chronic arthritis was induced by intraarticular injections of ovalbumin in immunized rabbits. Systemic inflammation was boosted in these rabbits by receiving a hyperlipidemic diet after producing an endothelial lesion in the femoral arteries. A group of these rabbits were treated with CS (100mg/kg/day). At sacrifice, synovial membranes were isolated, and cyclooxygenase-2 (COX-2) and chemokine (C-C motif) ligand 2 (CCL2) mRNA, as well as protein expression were assayed by quantitative real-time polymerase chain reaction (RT-PCR) and western blot studies. Histological synovial examination was also carried out employing the histopathological synovitis score (Krenn scale). RESULTS: CS diminished both gene expression and protein synthesis of COX-2 and CCL2, and the histopathological score of the synovial membrane, when compared to untreated rabbits. In fact, CS partially prevented the intimal layer proliferation and the inflammatory cell infiltration in the synovial membrane, which was observed in non-treated animals. CONCLUSION: CS reduced the inflammatory response of the synovial membrane, as well as decreased the synovial histopathological lesions in our animal model. Further studies are warranted to demonstrate whether CS might be beneficial in the treatment of inflammatory arthritis.

Long-term NSAID treatment directly decreases COX-2 and mPGES-1 production in the articular cartilage of patients with osteoarthritis.

OBJECTIVE: To simultaneously study the effect of a selective cyclooxygenase-2 (COX-2) inhibitor and that of a classic non-steroidal anti-inflammatory drug (NSAID) on the expression of pro-inflammatory genes in the cartilage of patients with severe knee osteoarthritis (OA) and in cultured human OA chondrocytes. METHODS: A 3-month clinical trial was carried out on 30 patients with severe knee OA scheduled for knee replacement surgery. Patients were randomized into two groups: patients treated with celecoxib (CBX) and patients treated with aceclofenac (ACF). OA patients who did not want to be treated served as the control group. After surgery, cartilage was processed for molecular biology studies. We also employed cultured chondrocytes from different OA patients to examine NSAID effects on pro-inflammatory gene expression in cells stimulated with interleukin (IL)-1beta. RESULTS: Both CBX and ACF inhibited COX-2, microsomal prostaglandin E synthase-1 (mPGES-1) and inducible nitric oxide synthase (iNOS) synthesis in the articular cartilage of OA patients. In cultured chondrocytes, both NSAID decreased COX-2 and mPGES-1 synthesis and prostaglandin E2 (PGE2) release induced by IL-1beta, while no effect was observed on nitric oxide or iNOS synthesis. In OA patients, only CBX decreased tumor necrosis factor alpha and IL-1beta expression in the cartilage, while both NSAID diminished IL-1beta induced cytokine synthesis in cultured OA chondrocytes. CONCLUSIONS: Both NSAID diminished PGE2 release and induced a decrease in COX-2 and mPGES-1 synthesis in the cartilage from OA patients and in OA chondrocytes. These data suggest that prolonged therapy with PGE2 blocking agents decreases PGE2 production not only by direct inhibition of COX-2 activity, but also by down-regulating COX-2 and mPGES-1 synthesis in the cartilage. However, CBX and ACF seem to have a different anti-inflammatory profile in controlling pro-inflammatory gene expression in the cartilage.

[Tics in childhood]. / Tics en la infancia.

INTRODUCTION: Tics in infancy often cause problems in social relationships of children and worry to their immediate family. We review some aspects of these abnormal movements and mention Gilles de la Tourette disease, discussing the graduation from simple tics to the more severe tics which occur in this illness. DEVELOPMENT: Tics are the commonest abnormal movements in infancy, when paroxystic disorders are excluded. We review the scant progress made in more than 100 years regarding their aetiology and pathogenesis. Current strategies for the treatment of tics are considered (not only pharmacological) and choice of drug depending on associated disorders.

[Sturge-Weber syndrome: experience with 14 cases]. / Síndrome de Sturge-Weber: Experiencia en 14 casos.

OBJECTIVE: The objective of this study was to review the cases of Sturge-Weber syndrome (SWS) diagnosed and followed-up in our center over the last 25 year period in order to evaluate their clinical characteristics, evolution and therapeutical response. PATIENTS AND METHODS: A retrospective review of the records of patients diagnosed of SSW (facial nevus flammeus at least over the first branch of the trigeminal nerve and ipsilateral leptomeningeal angioma) was performed. RESULTS: Fifteen patients were found in our records, with one of them being excluded from the study due to the lack of follow-up. From the remaining 14, 11 had been diagnosed before the age of 18 months. Nevus flammeus was located on the right side in 8 cases, bilaterally in 3 and on the left side in the other 3 patients. Four cases had glaucoma, 3 of which had good evolution after trabeculotomy. Thirteen of the 14 patients had seizures, usually contralateral to the nevus flammeus. The main drugs used were phenytoin, phenobarbital, valproic acid and carbamazepine. Ten of the 13 patients treated had a good therapeutical response. The EEG was abnormal in 12 patients, two of them occurring during the follow-up period. The main abnormality found was an interhemispherical asymmetry. Nine patients developed hemiparesis. In reference to the neuroimaging. MR was better than CT in evaluating parenchymatous atrophy, which was present in all patients, and the abnormalities of the white and grey matters (9 and 8 patients, respectively). CONCLUSIONS: Early evaluation of newborns with nevus flammeus affecting the first branch of the trigeminal nerve must be done, including an MR with contrast and an ophthalmological exam.