Search

The cornerstone in the treatment of locally advanced rectal cancer (LARC) is neoadjuvant chemoradiotherapy (nCRT) followed by total mesorectal excision. Reliable predictors of response to nCRT in LARC remain an unmet need in colorectal cancer research. This study used high throughput DNA analysis to investigate genetic differences between highly responsive tumors and tumors resistant to nCRT.

Background: Our previous study has identified variant rs745430558 in the SMAD4 gene promoter as potential biomarker for adenocarcinoma of the pancreas. The allele delTT (10T instead of 12T) was present in malignant pancreatic tissue with a prevalence of 88%. As analysis of cfDNA in liquid biopsy represents a noninvasive approach for the diagnosis and monitoring of malignancies, the aim of this study was to determine the presence of 12T and 10T alleles in the peripheral blood of patients with suspected pancreatic malignancy. Material and Methods: The study was performed using cell-free DNA (cfDNA) isolated from the serum of 15 patients with morphological alterations of the pancreas. The presence of 12T and 10T alleles was assessed by allele specific quantitative real-time PCR. Results: Of 15 analyzed samples, 13 were diagnosed with adenocarcinoma of the pancreas (AcP), 1 with neuroendocrine tumor (NET), and 1 with pancreatitis. The 10T allele was present in 84.7% of cases with AcP and also in the sample from the patient with NET. In patient with pancreatitis only the 12T allele was detected. Conclusion: Our research has shown that the results of liquid biopsy of patients with AcP are in agreement with tissue specimens analysis. Targeted detection of the rs745430558 10T variant in patients with suspected pancreatic malignancies could be a potential biomarker for diagnosis of AcP in the future.

Colorectal cancer (CRC) is a heterogeneous disease that ranks third and second globally in terms of incidence and mortality rates, respectively. Five-year survival of patients with CRC is approximately 90% if diagnosed in the early stages, and only 13% if the advance disease is present. About 25% of patients already have CRC metastases (mCRC) with the primary CRC diagnosis, while half of the patients will develop metastases with further disease progression. The most common organ in which CRC metastasizes is the liver (colorectal cancer liver metastasis, CRLM). Almost half of CRC patients will die due to complications caused by the presence of metastases, so it is extremely important to discover new therapeutic approaches, as well as prognostic and predictive biomarkers, in order to reduce such a high mortality rate. In the era of personalized medicine, various treatment modalities are available to CRC and mCRC patients, including resective surgery, systemic chemotherapy, and novel targeted biologics, which significantly improved the outcome of CRC patients. The main goal of neoadjuvant systemic chemotherapy is to render currently unresectable disease amenable to resection. The standard cytotoxic drugs used in systemic chemotherapy for the treatment of CRC are: 5-fluorouracil (5-FU), oxaliplatin, and irinotecan applied as single agents or combined. It has been shown that the combination of systemic chemotherapy with targeted biological agents (e.g., bevacizumab which targets vascular endothelial growth factor) leads to a better therapy response compared to the use of systemic chemotherapy alone. MicroRNA (miRNA) molecules belong to a large class of small regulatory non-coding single-stranded RNA molecules that exert negative post-transcriptional regulation of gene expression. MiRNAs are involved in the regulation of fundamental cellular processes such as cell proliferation, differentiation and death, thus these molecules have been proposed as one of the regulators of

Kolorektalni karcinom predstavlja heterogenu bolest koja zauzima treće i drugo mesto na svetu po stepenu incidence i stopi mortaliteta, respektivno. Poznato je da mikroRNK molekuli imaju ključne uloge u procesu patogeneze, progresije i metastaziranja kolorektalnog karcinoma, ali i rezistenciji na hemioterapiju. U različitim tumorima je pokazano da hsa-miR-93-5p može imati onkogenu, ali i tumor-supresorsku ulogu. Ovaj rad ima za cilj da predstavi dosadašnja saznanja o ulozi hsa-miR-93-5p u procesima vezanim za kolorektalnu karcinogenezu, metastaziranje i odgovor na hemioterapiju kod pacijenata sa kolorektalnim karcinomom. Rad takođe razmatra hsa-miR-93-5p kao potencijalni prognostički i prediktivni biomarker i primenu ovog molekula u kliničkoj praksi., Colorectal cancer is a heterogeneous disease that ranks third and second globally in terms of incidence and mortality rates, respectively. MicroRNAs have been implicated in the growth, progression, metastasis and response to therapy of different tumors, including colorectal cancer. Hsa-miR-93-5p has been reported to have oncogenic and tumor-suppressive roles in different tumor kinds. This review article aims to present the current knowledge on the role of hsa-miR-93-5p in the processes related to colorectal carcinogenesis, metastasis and response to chemotherapy in patients with primary and metastatic colorectal cancer. Also, the role of hsa-miR-93-5p as a potential prognostic and predictive biomarker and application of this molecule in the clinical practice is described.

In colorectal cancer (CRC), inactivation of SMAD4 occurs early in the disease development and SMAD4 represents one of key driver genes in progression and metastasis. Loss of SMAD4 protein expression is a relatively common feature of sporadic colorectal cancers, and it was observed to be even more frequent in tumors of patients with early onset disease and also more frequent in microsatellite stable tumors. Pathogenic variants in the SMAD4 gene are usually missense or nonsense mutations, and they are more frequent in the C-terminal domain. The aim of this study was to perform genetic analysis of SMAD4 C-terminal domain in colorectal cancer patients with early onset disease and microsatellite stable tumors. This pilot study was conducted with a purpose of investigating if such genetic screening strategy would be useful for diagnostic purposes in this specific subgroup of CRC patients. The study was conducted in a selected set of DNA samples extracted from the tumors of CRC patients who had less than 50 years at the time of diagnosis. Genetic analysis of C-terminal domain has encompassed analysis of exons 9, 10, 11 and 12 of the SMAD4 gene by PCR and direct DNA sequencing. Among the twenty analyzed tumor DNAs, one sample was found to harbor a SMAD4 variant: NC_000018.9:g.48591918C gt T; (NM005359.5: c.1081C gt T; Arg361Cys). The variant was discovered in exon 9, affecting the codon 361, which represents a mutational hot spot within the SMAD4 gene. This variant was discovered in homozygous state in the tumor of a 47 yr old female with T3 stage carcinoma of the right colon. Considering the incidence and functional consequences of SMAD4 exon 9 variants, the screening of this region could be a useful low cost strategy for the genetic analysis of colorectal tumors from patients with early onset disease, as well as for susceptibility testing.

This study aimed to examine the expression pattern of tumoral and circulating miR-93-5p in patients with colorectal cancer (CRC) liver metastasis (CRLM) and to explore its predictive and prognostic potential. CRLM tissue, surrounding non-tumor liver tissue, and serum were obtained from 35 patients with CRLM. The expression pattern of tissue and circulating miR-93-5p in patients with CRLM was determined using quantitative polymerase chain reaction, using miR-16-5p for normalization. Sample-based cut-off values for CRLM and serum miR-93-5p expression were calculated using Receiver Operating Characteristic curve analysis to stratify the patients into high and low miR-93-5p expression groups which were that compared with patients??? clinicopathological data, therapy response, one-year disease-free survival, and disease recurrence. Relative miR-93-5p expression was higher in CRLM in comparison to the non-metastatic liver tissue (p lt 0.001). CRLM miR-93-5p expression showed moderate negative correlation with carcinoembryonic antigen levels (r=???0.406; p=0.016). There were no differences in high-/low-miR-93-5p expression and therapy responders vs. non-responders, which was confirmed in vitro using metastatic and normal colonic cells SW620 and HCEC-1CT, respectively. No difference was observed in one-year recurrence-free survival in patients with high vs. low miR-93-5p expression in CRLM or serum. However, high miR-93-5p serum levels were significantly associated with early disease recurrence (p=0.035). In conclusion, miR-93-5p serum levels could be potentially used as a prognostic factor for early disease recurrence in CRLM patients.

Cerium oxide nanoparticles (nCeO2) have widespread applications, but they can be hazardous to the environment. Some reports indicate the toxic effect of nCeO2 on tested animals, but literature data are mainly contradictory. Coating of nCeO2 can improve their suspension stability and change their interaction with the environment, which can consequently decrease their toxic effects. Herein, the exopolysaccharides levan and pullulan, due to their high water solubility, biocompatibility, and ability to form film, were used to coat nCeO2. Additionally, the monosaccharide glucose was used, since it is a common material for nanoparticle coating. This is the first study investigating the impact of carbohydrate-coated nCeO2 in comparison to uncoated nCeO2 using different model organisms. The aim of this study was to test the acute toxicity of carbohydrate-coated nCeO2 on the bacterium Vibrio fischeri NRRL B-11177, the crustacean Daphnia magna, and zebrafish Danio rerio. The second aim was to investigate the effects of nCeO2 on respiration in Daphnia magna which was performed for the first time. Finally, it was important to see the relation between Ce bioaccumulation in Daphnia magna and Danio rerio and other investigated parameters. Our results revealed that the coating decreased the toxicity of nCeO2 on Vibrio fischeri. The coating of nCeO2 did not affect the nanoparticles’ accumulation/adsorption or mortality in Daphnia magna or Danio rerio. Monitoring of respiration in Daphnia magna revealed changes in CO2 production after exposure to coated nCeO2, while the crustacean's O2 consumption was not affected by any of the coated nCeO2. In summary, this study revealed that, at 200 mg L−1, uncoated and carbohydrate-coated nCeO2 are not toxic for the tested organisms, however, the CO2 production in Daphnia magna is different when they are treated with coated and uncoated nCeO2. The highest production was in glucose and levan-coated nCeO2 according to their highest suspension stabi

SMAD4 protein loss is a relatively common feature of sporadic colorectal cancers (CRC), and it was observed to be even more frequent in early-age onset CRC patients and microsatellite stable (MSS) tumors. Pathogenic variants in the SMAD4 gene are usually missense or nonsense mutations, and they are more frequent in the C-terminal domain. The aim of this study was to perform genetic analysis of SMAD4 C-terminal domain of MSS early-age onset CRC patients. This pilot study was conducted with a purpose of investigating if such genetic screening strategy would be useful for diagnostic purposes in this specific subgroup of CRC patients.

Purpose: There are limited data on expression of epithelial-mesenchymal transition (EMT) markers in patients with colorectal liver metastases (CRLM). The study aim was to evaluate the expression and prognostic significance of E-cadherin (CDH1), fibronectin (FN1) and vimentin (VIM) in patients with CRLM after curative-intent liver resection. Patients and Methods: Thirty patients with CRLM managed by curative-intent liver resection were included in this prospective pilot study. Blood samples, colorectal liver metastases and surrounding non-tumor liver tissue were collected. Expression of CDH1, FN1 and VIM was analyzed by quantitative real-time polymerase chain reaction. Expression in CRLM and non-tumor liver tissue was compared, while expression in serum was correlated with CRLM expression. One-year recurrence-free survival was compared between patients with low and high CDH1, FN1 and VIM expression. Results: The expression of CDH1 was similar in CRLM and non-tumor liver tissues, while FN1 and VIM expression was significantly lower in metastatic tissue (P=0.003 and pP lt 0.001, respectively). Serum expression of CDH1 and VIM was detected in 66.7% and 93.3% of patients, respectively, while FN1 was not detected in any of the patients. The correlation of CDH1 and VIM expression between CRLM and serum was not statistically significant. Decreased CDH1 expression in CRLM and decreased VIM expression in serum were associated with early recurrence after surgical treatment of CRLM. Conclusion: Lower expression of CDH1 in CRLM and lower serum expression of VIM were found to be associated with early recurrence after liver resection for CRLM.

Metastatic colorectal cancer (mCRC) patients are treated with standard chemotherapeutic drugs in the form of FOLFOX and FOLFIRI regimens. There are no reliable markers that could predict response to chemotherapy for mCRC. TGF-beta signaling which interacts with microRNA (miRNA) network has important roles in tumor progression and chemotherapy resistance, thus the interplay between TGF-beta signaling and miRNAs could be crucial for treatment response. The aim of this study was to analyze the effect of chemotherapy for mCRC on TGF-beta signaling and related miRNAs. Hsa-miR-17-5p, hsa-miR-21-5p and hsa-miR-93-5p were selected out of 316 miRNAs with multiple targets within the TGF-beta signaling by in silico analysis. SW620 cells were treated with chemotherapeutic drugs for mCRC for 1, 3 and 6 days and expression of selected miRNAs, PAI-1, CDH1 and VIM was measured. Expression of TGF-beta signaling-related hsa-miR-17-5p, hsa-miR-21-5p and hsa-miR-93-5p was time-dependently altered in SW620 cells treated with chemotherapeutics for mCRC. The expression of hsa-miR-93-5p remained downregulated after 6 days under combined treatments FOX and FIRI as well as the hsa-miR-17-5p expression under FIRI. Chemotherapy regimens for mCRC increased expression of a major TGF-beta signaling target gene PAI-1, independently of the selected miRNAs expression. These treatments also increased the expression of epithelial-mesenchymal transition (EMT) markers CDH1 and VIM on day 3 resulting in decrease of mesenchymal-like characteristics. However, their expression returned close to basal level on day 6. In conclusion, after initial response to chemotherapeutic drugs SW620 cells start to return close to the basal mesenchymal state while the long-term downregulated expression pattern of hsa-miR-93-5p and hsa-miR-17-5p makes them candidates worth testing as biomarkers for monitoring combined chemotherapeutic treatments therapy response in mCRC patients.

The use of nanomaterials in various commercial products and industrial processes has increased. Although the application of nanoparticles has great importance, some of them can be risky to human health and the environment. Cerium oxide nanoparticles CeO2 have been extensively investigated due to the excellent oxygen storage capacities on the basis of the redox transition between Ce3+ and Ce4+ and formation of oxygen vacancies on their surface. The effect of CeO2 on individual organisms and the ecosystem in general are not sufficiently explored. In this research we used CeO2, naked and coated with three different carbohydrates (glucose, pullulan or levan), to study their effect in three different model systems. We analyzed bioluminescence in gram-negative bacterium Vibrio fischeri, and acute toxicity in crustacean Daphnia magna and zebrafish Danio rerio. In all experiments the concentration of CeO2 nanoparticles was 200 mg/L. For all used types of nanoparticles, we observed bioluminescence inhibition of around 20%. The mortality rate of treated D. magna was 6.7% for glucose coated CeO2, 9.2% for naked and pullulan coated CeO2 and 18.2% for levan coated CeO2. Despite the adherence of nanoparticles aggregates to the outer surface of the chorion, no acute toxicity was observed for zebrafish embryos during the first 72 hours post fertilization. We also haven’t observed increased level of abnormalities among treated embryos during the first 72 hours post fertilization. In this study, we haven’t observed any toxic effect of CeO2 nanoparticles, but the extent of the nanoparticles’ uptake by the organism remains to be investigated. The effect of chronic exposure to CeO2 should also be analyzed.

Cucurbitacin E (CucE) is a highly oxidized steroid consisting of a tetracyclic triterpene. It is a member of a Cucurbitacin family of biomolecules that are predominantly found in Cucurbitaceae plants. CucE has already been identified as a potent anti-inflammatory compound. Here, its effects on CD4(+) T helper (Th) cells and macrophages, as the major encephalitogenic cells in the autoimmunity of the central nervous system, were investigated. Production of major pathogenic Th cell cytokines: interferon-gamma and interleukin-17 were inhibited under the influence of CucE. The effects of CucE on CD4+ T cells were mediated through the modulation of aryl hydrocarbon receptor, STAT3, Na kappa B, p38 MAPK, and miR-146 signaling. Further, production of nitric oxide and reactive oxygen species, as well as phagocytic ability, were inhibited in macrophages treated with CucE. These results imply that CucE possesses powerful antiencephalitogenic activity.