Potential association between PSCA rs2976395 functional variant and pancreatic cancer risk.

Correlated regions of systemic interindividual variation (CoRSIV) represent a small proportion of the human genome showing DNA methylation patterns that are the same in all human tissues, are different among individuals, and are partially regulated by genetic variants in cis. In this study we aimed at investigating single-nucleotide polymorphisms (SNPs) within CoRSIVs and their involvement with pancreatic ductal adenocarcinoma (PDAC) risk. We analyzed 29,099 CoRSIV-SNPs and 133,615 CoRSIV-mQTLs in 14,394 cases and 247,022 controls of European and Asian descent. We observed that the A allele of the rs2976395 SNP was associated with increased PDAC risk in Europeans (p = 2.81 × 10-5). This SNP lies in the prostate stem cell antigen gene and is in perfect linkage disequilibrium with a variant (rs2294008) that has been reported to be associated with risk of many other cancer types. The A allele is associated with the DNA methylation level of the gene according to the PanCan-meQTL database and with overexpression according to QTLbase. The expression of the gene has been observed to be deregulated in many tumors of the gastrointestinal tract including pancreatic cancer; however, functional studies are needed to elucidate the function relevance of the association.

Perioperative nutritional assessment and management of patients undergoing gastrointestinal surgery.

Malnutrition is a major issue in gastrointestinal perioperative situations, as only 40% of malnourished patients are finally treated. This literature review investigates the inconsistencies regarding the diagnostic approach to both preoperative and postoperative patients and the various underlying causes, as well as the efficiency of the various therapeutic regimens. A literature search was conducted until August 2023 in MEDLINE and Scopus. Clinical studies involving perioperative nutritional assessment in adult gastrointestinal surgery patients during the last 10 years were included in the present review. Finally, 19 articles were included in the study. Preoperative nutritional therapy is increasingly recognized as a key component of surgical care. Malnourished patients who are hospitalized and operated on, have significantly worse clinical results. Gastrointestinal postoperative malnutrition coexists with metabolic stress, as patients usually suffer from minor chronic inflammations; therefore, postoperative malnutrition is the result of a combination of the effects of inflammation and a lack of food intake. Postoperative malnutrition leads to prolonged hospitalizations and hospital complications and therefore the need to treat it is essential. There are many recognized tools for detecting malnutrition. However, all tools showed inconsistent results regarding their validity. Per os feeding after surgery, and dietary supplements when necessary, have been recommended. Therefore, it is very important to reduce malnutrition and define clear strategies towards that direction.

The Impact of Mechanical Bowel Preparation and Oral Antibiotics in Colorectal Cancer Surgery (MECCA Study): A Prospective Randomized Clinical Trial.

Background: Colorectal cancer surgery has been associated with surgical site infections (SSIs), leading to an increase in postoperative morbidity, length of stay and total cost. The aim of the present randomized study was to investigate the relationship between the preoperative administration of oral antibiotic therapy and SSI rate, as well as other postoperative outcomes in patients undergoing colorectal cancer surgery. Material and Methods: Patients who underwent colorectal cancer surgery in a university surgical department were included in the present study. Patients were randomized into two groups using the "block randomization" method. The intervention group received three doses of 400 mg rifaximin and one dose of 500 mg metronidazole per os, as well as mechanical bowel preparation the day before surgery. The control group underwent only mechanical bowel preparation the day before surgery. The study has been registered in ClinicalTrials.gov (NCT03563586). Results: Two hundred and five patients were finally included in the present study, 97 of whom received preoperative antibiotic therapy per os (intervention group). Patients of this group demonstrated a significantly lower SSI rate compared with patients who did not receive preoperative antibiotic therapy (7% vs. 16%, p = 0.049). However, preoperative antibiotic administration was not correlated with any other postoperative outcome (anastomotic leak, overall complications, readmissions, length of stay). Conclusions: Preoperative antibiotic therapy in combination with mechanical bowel preparation seemed to be correlated with a lower SSI rate after colorectal cancer surgery.

Polymorphisms in transcription factor binding sites and enhancer regions and pancreatic ductal adenocarcinoma risk.

Genome-wide association studies (GWAS) are a powerful tool for detecting variants associated with complex traits and can help risk stratification and prevention strategies against pancreatic ductal adenocarcinoma (PDAC). However, the strict significance threshold commonly used makes it likely that many true risk loci are missed. Functional annotation of GWAS polymorphisms is a proven strategy to identify additional risk loci. We aimed to investigate single-nucleotide polymorphisms (SNP) in regulatory regions [transcription factor binding sites (TFBSs) and enhancers] that could change the expression profile of multiple genes they act upon and thereby modify PDAC risk. We analyzed a total of 12,636 PDAC cases and 43,443 controls from PanScan/PanC4 and the East Asian GWAS (discovery populations), and the PANDoRA consortium (replication population). We identified four associations that reached study-wide statistical significance in the overall meta-analysis: rs2472632(A) (enhancer variant, OR 1.10, 95%CI 1.06,1.13, p = 5.5 × 10-8), rs17358295(G) (enhancer variant, OR 1.16, 95%CI 1.10,1.22, p = 6.1 × 10-7), rs2232079(T) (TFBS variant, OR 0.88, 95%CI 0.83,0.93, p = 6.4 × 10-6) and rs10025845(A) (TFBS variant, OR 1.88, 95%CI 1.50,1.12, p = 1.32 × 10-5). The SNP with the most significant association, rs2472632, is located in an enhancer predicted to target the coiled-coil domain containing 34 oncogene. Our results provide new insights into genetic risk factors for PDAC by a focused analysis of polymorphisms in regulatory regions and demonstrating the usefulness of functional prioritization to identify loci associated with PDAC risk.

Malignant Bowel Obstruction: A Retrospective Multicenter Cohort Study.

BACKGROUND: Malignant bowel obstruction (MBO) is a serious clinical entity that requires surgical intervention in almost 50% of cases. However, overall survival remains low even for operable cases. The aim of the present study was to investigate the correlation between patients' characteristics, perioperative details, histopathological results and postoperative outcomes of patients who were operated on due to MBO. METHODS: A retrospective search of patients who were operated on due to MBO in a university and a rural hospital was conducted. Patients' characteristics, perioperative details, histopathological results and postoperative outcomes were reported. Univariable and multivariable analysis was performed. RESULTS: Seventy patients were included with a mean age of 76.1 ± 10.6 years. The 30-day mortality rate was 18.6%, the Intensive Care Unit (ICU) admission rate was 17.1% and the mean length of stay (LOS) was 12.4 ± 5.7 days. Postoperative 30-day mortality was associated with increased age, known malignant recurrence, microscopically visible metastatic foci and defunctioning stoma creation. Colorectal malignancy type, sigmoid obstruction and primary anastomosis were correlated with decreased 30-day mortality. In addition, operation at the university hospital led to increased LOS, while stoma creation led to decreased LOS. Finally, ICU admission rates were increased for operations at university hospitals, at least one comorbidity, known malignant recurrence and longer preoperative waiting interval, whereas they were decreased for colorectal primary malignancy type. CONCLUSIONS: Surgery due to MBO leads to increased morbidity and mortality. Therefore, prospective studies are needed to highlight inter-patient differences regarding the best individualized therapeutic strategy.

A Strict Patient Selection Protocol Could Be the Key to Success for Transanal Minimally Invasive Surgery (TAMIS).

OBJECTIVES: In recent years, the local excision of benign rectal lesions or early-stage rectal cancers using minimally invasive surgical techniques has replaced radical interventions that caused impairment in patients' quality of life. The aim of the present study was to investigate the feasibility of transanal minimally invasive surgery (TAMIS), as well as its excision quality, its oncologic outcomes, and its impact on anorectal function. METHODS: Patients who underwent TAMIS at a single colorectal unit of a tertiary university hospital from 2015 until 2020 for benign rectal lesions or early-stage malignant rectal lesions, along with unsuitable patients for radical interventions, were included in the present study. RESULTS: Twenty-five patients underwent TAMIS for rectal lesions. Their median distance from the anal verge was 7 cm (range 4-12 cm) and their median size was 3.8 cm (range 2-6 cm). The median operative duration was 75 minutes (range 30-150 minutes) and the median hospitalization interval was 2 days (range 1-6 days). In addition, the negative resection rate was 100% and the recurrence rate was 4% during an average follow-up period of 30 months (range 3-36 months). Two patients (8%) presented short-term complications, and in 1 patient (4%) a hybrid technique was required. Seventeen patients (68%) reported moderate incontinence symptoms 6 weeks postoperatively that subsided in all patients 3 months postoperatively. CONCLUSIONS: TAMIS seemed to be a feasible technique with adequate oncologic outcomes and high excision quality, which preserved patients' quality of life. The impact of TAMIS on anorectal function after neoadjuvant chemoradiotherapy for rectal cancer should be further investigated, however.

Polymorphic variants involved in methylation regulation: a strategy to discover risk loci for pancreatic ductal adenocarcinoma.

INTRODUCTION: Only a small number of risk factors for pancreatic ductal adenocarcinoma (PDAC) has been established. Several studies identified a role of epigenetics and of deregulation of DNA methylation. DNA methylation is variable across a lifetime and in different tissues; nevertheless, its levels can be regulated by genetic variants like methylation quantitative trait loci (mQTLs), which can be used as a surrogate. MATERIALS AND METHODS: We scanned the whole genome for mQTLs and performed an association study in 14 705 PDAC cases and 246 921 controls. The methylation data were obtained from whole blood and pancreatic cancer tissue through online databases. We used the Pancreatic Cancer Cohort Consortium and the Pancreatic Cancer Case-Control Consortium genome-wide association study (GWAS) data as discovery phase and the Pancreatic Disease Research consortium, the FinnGen project and the Japan Pancreatic Cancer Research consortium GWAS as replication phase. RESULTS: The C allele of 15q26.1-rs12905855 showed an association with a decreased risk of PDAC (OR=0.90, 95% CI 0.87 to 0.94, p=4.93×10-8 in the overall meta-analysis), reaching genome-level statistical significance. 15q26.1-rs12905855 decreases the methylation of a 'C-phosphate-G' (CpG) site located in the promoter region of the RCCD1 antisense (RCCD1-AS1) gene which, when expressed, decreases the expression of the RCC1 domain-containing (RCCD1) gene (part of a histone demethylase complex). Thus, it is possible that the rs12905855 C-allele has a protective role in PDAC development through an increase of RCCD1 gene expression, made possible by the inactivity of RCCD1-AS1. CONCLUSION: We identified a novel PDAC risk locus which modulates cancer risk by controlling gene expression through DNA methylation.

Primary Squamous Cell Carcinoma of Colon and Rectum: A Systematic Review of the Literature.

Background - Objective: Primary colorectal squamous cell carcinoma is an extremely rare neoplasm with an incidence of 0.1 to 0.25 per 1,000 diagnosed colorectal carcinomas.The objective of this study was to evaluate its biological behavior and highlight the role of a surgical approach for its management.MethodsPubMed and Cohrane databases were independently searched (last search: April 10th, 2020) for articles concerning colorectal squamous cell carcinoma in adult population.Results: Seventy-one studies met predefined inclusion criteria and involved 99 patients (54.5% females) with an age of 56.98 ± 12.19 years (mean ± SD). The most frequent site of occurrence was the rectum (63.5%). Open surgery was conducted at 95% of patients, while 21.4% and 30.3% received neoadjuvant and adjuvant therapy respectively.Postoperative complications were developed in 31.3% of patients, while 6.1% died withing the first month following operation. Five-years survival rate was 49.5% (95% CI: 33.7%-63.4%). Female sex (HR: 0.24; 95% CI: 0.11-0.54; p-value: 0.001) and presence of postoperative complications (HR: 4.10; 95%CI: 1.47-1.46; p-value: 0.007) significantly affected the survival.Conclusions Colorectal Squamous Cell Carcinoma is a rare tumor with an aggressive behavior. Surgery is the standard of treatment for the colontumors, while the role of chemoradiotherapy is promising especially for rectal tumors. Further clinical trials are necessary to determine the preferred treatment approach.

Temporal Changes of Low Anterior Resection Syndrome Score after Sphincter Preservation: A Prospective Cohort Study on Repetitive Assessment of Rectal Cancer Patients.

Background: There is a relative shortage of studies directly addressing the postoperative rectal cancer patients' evacuatory dysfunction, as estimated by the low anterior resection syndrome (LARS) score at repeated assessment time-points. The aim of the present study was to prospectively evaluate the incidence of LARS at predefined time intervals during the first 3 years after sphincter preserving rectal cancer surgery and to enlighten the effect of identified risk factors.Materials and methods: Seventy-eight patients, who remained alive and recurrence-free 2 years after (ultra-) low anterior resection were prospectively assessed at 6, 12, 18, 24, 30 and 36 months postoperatively, using the LARS score as bowel dysfunction outcome measure. All patients have completed the 2-year follow-up functional assessment, while 56 and 37 of them have been evaluated up to the 30th and the 36th postoperative month, respectively.Results: The proportion of patients with "major and minor" LARS significantly decreased during the first 3 evaluations (up to 18 months) (74% vs 62% vs 35%, p = 0.0001). The tumor distance from the anal verge and the neoadjuvant radiotherapy were identified as risk factors for high LARS score at 6 months (p < 0.03). The tumor distance remained as risk factor throughout the entire follow-up. All patients with high tumors were alleviated from symptoms reflecting "major" or "minor" LARS at 18 months. Most patients (90%) after radiotherapy showed a high LARS score in the first semester, but improved afterwards.Conclusion: Overall, the LARS score improves in the majority of patients after 18 months, with low tumor height and radiation adversely affecting them. Our results may be useful in more accurately define the postoperative "functional course" of rectal cancer patients and in aiding their consultation on expected functional outcome.

Identification of Recessively Inherited Genetic Variants Potentially Linked to Pancreatic Cancer Risk.

Although 21 pancreatic cancer susceptibility loci have been identified in individuals of European ancestry through genome-wide association studies (GWASs), much of the heritability of pancreatic cancer risk remains unidentified. A recessive genetic model could be a powerful tool for identifying additional risk variants. To discover recessively inherited pancreatic cancer risk loci, we performed a re-analysis of the largest pancreatic cancer GWAS, the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4), including 8,769 cases and 7,055 controls of European ancestry. Six single nucleotide polymorphisms (SNPs) showed associations with pancreatic cancer risk according to a recessive model of inheritance. We replicated these variants in 3,212 cases and 3,470 controls collected from the PANcreatic Disease ReseArch (PANDoRA) consortium. The results of the meta-analyses confirmed that rs4626538 (7q32.2), rs7008921 (8p23.2) and rs147904962 (17q21.31) showed specific recessive effects (p<10-5) compared with the additive effects (p>10-3), although none of the six SNPs reached the conventional threshold for genome-wide significance (p < 5×10-8). Additional bioinformatic analysis explored the functional annotations of the SNPs and indicated a possible relationship between rs36018702 and expression of the BCL2L11 and BUB1 genes, which are known to be involved in pancreatic biology. Our findings, while not conclusive, indicate the importance of considering non-additive genetic models when performing GWAS analysis. The SNPs associated with pancreatic cancer in this study could be used for further meta-analysis for recessive association of SNPs and pancreatic cancer risk and might be a useful addiction to improve the performance of polygenic risk scores.

Association of Genetic Variants Affecting microRNAs and Pancreatic Cancer Risk.

Genetic factors play an important role in the susceptibility to pancreatic cancer (PC). However, established loci explain a small proportion of genetic heritability for PC; therefore, more progress is needed to find the missing ones. We aimed at identifying single nucleotide polymorphisms (SNPs) affecting PC risk through effects on micro-RNA (miRNA) function. We searched in silico the genome for SNPs in miRNA seed sequences or 3 prime untranslated regions (3'UTRs) of miRNA target genes. Genome-wide association data of PC cases and controls from the Pancreatic Cancer Cohort (PanScan) Consortium and the Pancreatic Cancer Case-Control (PanC4) Consortium were re-analyzed for discovery, and genotyping data from two additional consortia (PanGenEU and PANDoRA) were used for replication, for a total of 14,062 cases and 11,261 controls. None of the SNPs reached genome-wide significance in the meta-analysis, but for three of them the associations were in the same direction in all the study populations and showed lower value of p in the meta-analyses than in the discovery phase. Specifically, rs7985480 was consistently associated with PC risk (OR = 1.12, 95% CI 1.07-1.17, p = 3.03 × 10-6 in the meta-analysis). This SNP is in linkage disequilibrium (LD) with rs2274048, which modulates binding of various miRNAs to the 3'UTR of UCHL3, a gene involved in PC progression. In conclusion, our results expand the knowledge of the genetic PC risk through miRNA-related SNPs and show the usefulness of functional prioritization to identify genetic polymorphisms associated with PC risk.

Associations between pancreatic expression quantitative traits and risk of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal cancers. Its poor prognosis is predominantly due to the fact that most patients remain asymptomatic until the disease reaches an advanced stage, alongside the lack of early markers and screening strategies. A better understanding of PDAC risk factors is essential for the identification of groups at high risk in the population. Genome-wide association studies (GWAS) have been a powerful tool for detecting genetic variants associated with complex traits, including pancreatic cancer. By exploiting functional and GWAS data, we investigated the associations between polymorphisms affecting gene function in the pancreas (expression quantitative trait loci, eQTLs) and PDAC risk. In a two-phase approach, we analysed 13 713 PDAC cases and 43 784 controls and identified a genome-wide significant association between the A allele of the rs2035875 polymorphism and increased PDAC risk (P = 7.14 × 10-10). This allele is known to be associated with increased expression in the pancreas of the keratin genes KRT8 and KRT18, whose increased levels have been reported to correlate with various tumour cell characteristics. Additionally, the A allele of the rs789744 variant was associated with decreased risk of developing PDAC (P = 3.56 × 10-6). This single nucleotide polymorphism is situated in the SRGAP1 gene and the A allele is associated with higher expression of the gene, which in turn inactivates the cyclin-dependent protein 42 (CDC42) gene expression, thus decreasing the risk of PDAC. In conclusion, we present here a functional-based novel PDAC risk locus and an additional strong candidate supported by significant associations and plausible biological mechanisms.

Genome-wide scan of long noncoding RNA single nucleotide polymorphisms and pancreatic cancer susceptibility.

Pancreatic ductal adenocarcinoma (PDAC) is projected to become the second cancer-related cause of death by 2030. Identifying novel risk factors, including genetic risk loci, could be instrumental in risk stratification and implementation of prevention strategies. Long noncoding RNAs (lncRNAs) are involved in regulation of key biological processes, and the possible role of their genetic variability has been unexplored so far. Combining genome wide association studies and functional data, we investigated the genetic variability in all lncRNAs. We analyzed 9893 PDAC cases and 9969 controls and identified a genome-wide significant association between the rs7046076 SNP and risk of developing PDAC (P = 9.73 × 10-9 ). This SNP is located in the NONHSAG053086.2 (lnc-SMC2-1) gene and the risk allele is predicted to disrupt the binding of the lncRNA with the micro-RNA (miRNA) hsa-mir-1256 that regulates several genes involved in cell cycle, such as CDKN2B. The CDKN2B region is pleiotropic and its genetic variants have been associated with several human diseases, possibly though an imperfect interaction between lncRNA and miRNA. We present a novel PDAC risk locus, supported by a genome-wide statistical significance and a plausible biological mechanism.

Polygenic and multifactorial scores for pancreatic ductal adenocarcinoma risk prediction.

BACKGROUND: Most cases of pancreatic ductal adenocarcinoma (PDAC) are asymptomatic in early stages, and the disease is typically diagnosed in advanced phases, resulting in very high mortality. Tools to identify individuals at high risk of developing PDAC would be useful to improve chances of early detection. OBJECTIVE: We generated a polygenic risk score (PRS) for PDAC risk prediction, combining the effect of known risk SNPs, and carried out an exploratory analysis of a multifactorial score. METHODS: We tested the associations of the individual known risk SNPs on up to 2851 PDAC cases and 4810 controls of European origin from the PANcreatic Disease ReseArch (PANDoRA) consortium. Thirty risk SNPs were included in a PRS, which was computed on the subset of subjects that had 100% call rate, consisting of 839 cases and 2040 controls in PANDoRA and 6420 cases and 4889 controls from the previously published Pancreatic Cancer Cohort Consortium I-III and Pancreatic Cancer Case-Control Consortium genome-wide association studies. Additional exploratory multifactorial scores were constructed by complementing the genetic score with smoking and diabetes. RESULTS: The scores were associated with increased PDAC risk and reached high statistical significance (OR=2.70, 95% CI 1.99 to 3.68, p=2.54×10-10 highest vs lowest quintile of the weighted PRS, and OR=14.37, 95% CI 5.57 to 37.09, p=3.64×10-8, highest vs lowest quintile of the weighted multifactorial score). CONCLUSION: We found a highly significant association between a PRS and PDAC risk, which explains more than individual SNPs and is a step forward in the direction of the construction of a tool for risk stratification in the population.

Ag/Au Bimetallic Nanoparticles Inhibit Tumor Growth and Prevent Metastasis in a Mouse Model.

PURPOSE: To evaluate the antitumor efficacy of Ag3Au1Trp1:2NPs in a SCID mouse cancer model, with respect to their effect on tumor growth, on tumor's metastatic potential and the underlying molecular mechanism. SUBJECTS AND METHODS: Ag3Au1Trp1:2NPs were radiolabeled with Gallium-68 and the biodistribution was studied in Swiss mice without tumors and in SCID mice bearing tumors. SCID mice received intratumoral Ag3Au1Trp1:2NPs and tumor size was measured using calipers. Lung and liver tissues were extracted and studied microscopically for the detection of any metastatic sites. Changes in the Caspase-3 and TNF-related apoptosis-inducing ligand (TRAIL) were also investigated using real-time PCR and Western blot techniques, respectively. RESULTS: In the 4T1 tumor-bearing SCID mice, Ag3Au1Trp1:2NPs showed quick passive accumulation at tumor sites at 30 mins post-injection. Mice that received the highest dose of NPs (5.6mg/mL) demonstrated a 1.9-fold lower tumor volume compared to that of the control group at 11 days post-injection, while mice that did not receive NPs showed metastatic sites in liver and lung. Extracted tumor tissue of treated mice revealed increased Casp-3 mRNA levels as well as elevated TRAIL protein levels. CONCLUSION: Based on our results, Ag3Au1Trp1:2NPs express anti-tumor and anti-metastatic effects in vivo. Ag3Au1Trp1:2NPs also reach tumor site via the enhancement and retention effect which results in the apoptotic death of cancerous cells selectively via the extrinsic TRAIL-dependent pathway.

The Interplay between Mucosal Microbiota Composition and Host Gene-Expression is Linked with Infliximab Response in Inflammatory Bowel Diseases.

Even though anti-TNF therapy significantly improves the rates of remission in inflammatory bowel disease (IBD) patients, there is a noticeable subgroup of patients who do not respond to treatment. Dysbiosis emerges as a key factor in IBD pathogenesis. The aim of the present study is to profile changes in the gut microbiome and transcriptome before and after administration of the anti-TNF agent Infliximab (IFX) and investigate their potential to predict patient response to IFX at baseline. Mucosal biopsy samples from 20 IBD patients and nine healthy controls (HC) were examined for differences in microbiota composition (16S rRNA gene sequencing) and mucosal gene expression (RT-qPCR) at baseline and upon completion of IFX treatment, accordingly, via an in silico pipeline. Significant differences in microbiota composition were found between the IBD and HC groups. Several bacterial genera, which were found only in IBD patients and not HC, had their populations dramatically reduced after anti-TNF treatment regardless of response. Alpha and beta diversity metrics showed significant differences between our study groups. Correlation analysis revealed six microbial genera associated with differential expression of inflammation-associated genes in IFX treatment responders at baseline. This study shows that IFX treatment has a notable impact on both the gut microbial composition and the inflamed tissue transcriptome in IBD patients. Importantly, our results identify enterotypes that correlate with transcriptome changes and help differentiate IFX responders versus non-responders at baseline, suggesting that, in combination, these signatures can be an effective tool to predict anti-TNF response.

Ag/Au bimetallic nanoparticles induce apoptosis in human cancer cell lines via P53, CASPASE-3 and BAX/BCL-2 pathways.

Au/Ag bimetallic nanoparticles (BNPs) exhibit a wide range of excellent electronic, chemical, biological, mechanical and thermal properties due to synergistic effects. However, critical questions regarding stability, biocompatibility and their cytotoxic effects remain to be answered. In this study, Ag/Au BNPs have been synthesized as "alloy" via a chemical reduction method using double molar excess of tryptophan [ν(M):ν(Trp) = 1:2]. We then estimated their toxicity in HCT116, 4T1, HUH7 and HEK293 cell lines in monocellular and spheroid cultures. Ag/Au nanoparticles with metal ratio 3:1, had the maximal antitumor effect in cancer cell lines, while the toxicity was found significantly decreased in non-cancerous cell lines. Our results were also compared to previous data regarding Ag/Au using single molar excess of tryptophan [ν(M):ν(Trp) = 1:1], suggesting that tryptophan has a protective effect on HEK293 and not in cancer cells. Aiming to investigate the molecular mechanism behind nanopartricles cytotoxicity, we studied the expression of cell cycle and apoptosis related genes on HCT116, 4T1, and HUH7 monocellular culture. Hence, we showed that bimetallic cytotoxicity is mediated via the caspase and the p53/Bax/Bcl-2 apoptotic pathway. In conclusion, our study suggests tryptophan ratio along with metal ratio used in Ag/Au BNPs as a successful way to control the toxicity in cancer cells towards non-cancerous cells, underlying the potency of bimetallic nanoparticles as selective anti-tumor agents.

Identification of Methylation Profiles of Cancer-related Genes in Circulating Tumor Cells Population.

BACKGROUND: We performed an epigenetic analysis of the first exon of the hVIM gene and the SFRP2 in circulating tumor cells (CTCs) and correlation with the corresponding primary colorectal cancer (CRC) tissue. PATIENTS AND METHODS: CTCs detection in 52 colorectal cancer patients was managed by a multi-marker immunomagnetic method with the use of quantum dots (QDs). To determine methylation levels we used high-resolution melting (HRM) technology. RESULTS: In the case of VIM we found 76.9% methylated samples, compared to 53.8% in tissue samples. Regarding SFRP2 promoter methylation levels in tissue and CTCs samples, 67.3% and 73.1%, were found methylated respectively. Correlation analysis of methylation levels with KRAS and BRAF mutations (performed in our previous study) demonstrates that high-methylation epigenotype strongly correlates to BRAF mutation. CONCLUSION: CTCs is a promising diagnostic tool. The combination of genetic mutations and epigenetic aberrations specifically in CTCs, will ameliorate CRC diagnosis in the future.

Functional single nucleotide polymorphisms within the cyclin-dependent kinase inhibitor 2A/2B region affect pancreatic cancer risk.

The CDKN2A (p16) gene plays a key role in pancreatic cancer etiology. It is one of the most commonly somatically mutated genes in pancreatic cancer, rare germline mutations have been found to be associated with increased risk of developing familiar pancreatic cancer and CDKN2A promoter hyper-methylation has been suggested to play a critical role both in pancreatic cancer onset and prognosis. In addition several unrelated SNPs in the 9p21.3 region, that includes the CDNK2A, CDNK2B and the CDNK2B-AS1 genes, are associated with the development of cancer in various organs. However, association between the common genetic variability in this region and pancreatic cancer risk is not clearly understood. We sought to fill this gap in a case-control study genotyping 13 single nucleotide polymorphisms (SNPs) in 2,857 pancreatic ductal adenocarcinoma (PDAC) patients and 6,111 controls in the context of the Pancreatic Disease Research (PANDoRA) consortium. We found that the A allele of the rs3217992 SNP was associated with an increased pancreatic cancer risk (ORhet=1.14, 95% CI 1.01-1.27, p=0.026, ORhom=1.30, 95% CI 1.12-1.51, p=0.00049). This pleiotropic variant is reported to be a mir-SNP that, by changing the binding site of one or more miRNAs, could influence the normal cell cycle progression and in turn increase PDAC risk. In conclusion, we observed a novel association in a pleiotropic region that has been found to be of key relevance in the susceptibility to various types of cancer and diabetes suggesting that the CDKN2A/B locus could represent a genetic link between diabetes and pancreatic cancer risk.

Prediction of response to combination chemotherapy with irinotecan in Greek patients with metastatic colorectal cancer.

BACKGROUND: The aim of our study was to analyze the possible relationships between treatment efficacy, and germinal gene polymorphisms linked to the irinotecan in combination with bevasizumab or panitumumab and capecitabine or 5-FU that has been routinely used in our practice, in the management of metastatic colorectal cancer (CRC). MATERIALS AND METHODS: Ninety-four Greek with histologically proven metastatic CRC were included in the study. Treatment was administered until disease progression or unacceptable toxicity, for a maximum of eight cycles. Patients were stratified into stable disease. (SD) and progressive disease. (PD). Associations between clinical data, KRAS, UGT1A1. (UGT1A1*28) and DPD (IVS14+1 G. > A) polymorphisms, and toxicity were analyzed. RESULTS: Fifty-eight (61.70%) patients were characterized with SD disease and 36 (38.30%) with PD. There were not statistical significant differences between carriers of KRAS mutated alleles between SD and PD groups. No significant difference was found between response rates and toxicity and DPD or UGT1A1 genotypes. Our results suggested that determination of DPD or UGT1A1 genotypes could not be useful for predicting severe toxicity of irinotecan in our population. CONCLUSIONS: The clinical significance of the findings requires replication in larger populations. Furthermore, as 5.FU and irinotecan metabolism is complex, numerous genes in addition to DPD and UGT1A1 should be investigated.