MicroRNA-193a-3p as a Valuable Biomarker for Discriminating between Colorectal Cancer and Colorectal Adenoma Patients.

Specific markers for colorectal cancer (CRC), preceded by colorectal adenoma (pre-CRC), are lacking. This study aimed to investigate whether microRNAs (miR-19a-3p, miR-92a-3p, miR-193a-3p, and miR-210-3p) from tissues and exosomes are potential CRC biomarkers and compare them to existing biomarkers, namely carcinoembryonic antigen (CEA) and carbohydrate antigen (CA) 19-9. MiRNA was isolated in the samples of 52 CRC and 76 pre-CRC patients. Expression levels were analyzed by RT-qPCR. When comparing pre-CRC and CRC tissue expression levels, only miR-193a-3p showed statistically significant result (p < 0.0001). When comparing the tissues and exosomes of CRC samples, a statistically significant difference was found for miR-193a-3p (p < 0.0001), miR-19a-3p (p < 0.0001), miR-92a-3p (p = 0.0212), and miR-210-3p (p < 0.0001). A receiver-operating characteristic (ROC) curve and area under the ROC curve (AUC) were used to evaluate the diagnostic value of CEA, CA 19-9, and miRNAs. CEA and CA 19-9 had good diagnostic values (AUCs of 0.798 and 0.668). The diagnostic value only of miR-193a-3p was highlighted (AUC = 0.725). The final logistic regression model, in which we put a combination of CEA concentration and the miR-193a-3p expression level in tissues, showed that using these two markers can distinguish CRC and pre-CRC in 71.3% of cases (AUC = 0.823). MiR-193a-3p from tissues could be a potential CRC biomarker.

The Role of Hyperthermia in Potentiation of Anti-Angiogenic Effect of Cisplatin and Resveratrol in Mice Bearing Solid Form of Ehrlich Ascites Tumour.

The aim of this study was to investigate the therapeutic potential of resveratrol in combination with cisplatin on the inhibition of tumour angiogenesis, growth, and macrophage polarization in mice bearing the solid form of an Ehrlich ascites tumour (EAT) that were exposed to whole-body hyperthermia treatment. In addition, we investigated whether a multimodal approach with hyperthermia and resveratrol could abolish cisplatin resistance in tumour cells through the modulation of histone deacetylase (HDAC) activity and levels of heat shock proteins (HSP70/HSP90) and contribute to the direct toxicity of cisplatin on tumour cells. The tumour was induced by injecting 1 × 106 EAT cells subcutaneously (sc) into the thighs of Balb/c mice. The mice were treated with resveratrol per os for five consecutive days beginning on day 2 after tumour injection and/or by injecting cisplatin intraperitoneally (ip) at a dose of 2.5 mg/kg on days 10 and 12 and at a dose of 5 mg/kg on day 15. Immediately thereafter, the mice were exposed to systemic hyperthermia for 15 min at a temperature of 41 °C. The obtained results showed that the administration of resveratrol did not significantly contribute to the antitumour effect of cisplatin and hyperthermia, but it partially contributed to the immunomodulatory effect and to the reduction of cisplatin toxicity and to a slight increase in animal survival. This treatment schedule did not affect microvessel density, but it inhibited tumour growth and modulated macrophage polarization to the M1 phenotype. Furthermore, it abolished the resistance of tumour cells to cisplatin by modulating HDAC activity and the concentration of HSP70 and HSP90 chaperones, contributing to the increased lifespan of mice. However, the precise mechanism of the interaction between resveratrol, cisplatin, and hyperthermia needs to be investigated further.

Resveratrol and its nanocrystals: A promising approach for cancer therapy?

There has been a significant research interest in nanocrystals as a promising technology for improving the therapeutic efficacy of poorly water-soluble drugs, such as resveratrol. Little is known about the interaction of nanocrystals with biological tissue. The aim of this study was to investigate the potential use of resveratrol (RSV) and its nanocrystals (NANO-RSV) as antitumor agents in Ehrlich ascites tumour (EAT)-bearing mice and the interaction of nanocrystals with biological tissue through biochemical and histological changes of kidney, liver and EAT cells. After intraperitoneal injection of 2.5 × 106 cells into the abdominal cavity of mice, treatment of animals was started next day by injecting RSV or NANO-RSV at a dose of either 25 or 50 mg/kg every other day for 14 days. The results show that the administration of resveratrol and its nanocrystals lead to significant reductions in the proliferation of tumour cells in the abdominal cavity, and a reduction of the number of blood vessels in the peritoneum, with low systemic toxicity. In histopathological examinations, greater hepatocellular necrosis and apoptosis, hepatic fibrosis around the central vein and degeneration with minor fatty change were observed with RSV than with NANO-RSV. Inflammation with proximal tubular necrosis and renal glomerulus swelling were also observed, together with slight elevation of several biochemical parameters in both the RSV and NANO-RSV groups. In order to increase the beneficial effects and reduce risks associated with resveratrol nanocrystals, additional factors such as dose, genetic factors, health status, and the nature of the target cells should also be considered.

Non-phosphorylated Tyr-1248 form of human epidermal growth factor receptor 2 (HER2) predicts resistance to trastuzumab therapy and poor disease-free survival of HER2-positive breast cancer patients.

AIM: To determine the predictive value of phosphorylated human epidermal growth factor receptor 2 (pHER2Y1248) status in breast cancer (BC) patients undergoing trastuzumab-based adjuvant therapy. METHODS: Immunohistochemical status of pHER2Y1248, EGFR/HER1, HER3, and HER4 was determined in 124 consecutive HER2-positive BC patients (median age [range]=57 years [49.0-64.0]) treated at the University Hospital for Tumors, Zagreb, between 2008 and 2011. The median follow-up was 84 months (60.0-84.0). Prognostic factors of disease free survival (DFS) rate were evaluated with Kaplan-Meier/log-rank test and Cox regression analysis. RESULTS: pHER2Y1248, HER1, HER3, and HER4 were expressed in 66.1%, 9.7%, 70.2%, and 71.0% of patients, respectively. Disease progression (DP) was observed in 17.1% of pHER2Y1248-positive and 47.6% of pHER2Y1248-negative BCs (P=0.001). Kaplan-Meier analysis showed a worse five-year DFS in pHER2Y1248-negative patients who were older than 60 years (P<0.001) and had positive lymph node status (P<0.001); tumor size >2.0 cm (P<0.001); higher histological grade (P<0.001); HER2E intrinsic subtype (P<0.001), negative hormone receptors (P<0.001); negative HER1 status (P<0.001), positive HER3 (P=0.002); and/or positive HER4 (P=0.002) status. The only negative prognostic factor for five-year DFS in multivariate Cox regression analysis was pHER2Y1248-negative (hazard ratio [HR] 3.6, 95% confidence interval [CI] 1.8-7.2, P<0.001) and lymph node-positive status (HR 3.6, 95% CI 1.3-9.8, P=0.014). CONCLUSION: pHER2Y1248 predicts sensitivity to trastuzumab and a better five-year DFS regardless of any other prognostic parameter. In HER2-positive BC patients. Non-phosphorylated HER2Y1248 is a strong predictor of trastuzumab resistance and a poor DFS.

Impact of oestrogen and progesterone receptor expression in the cancer cells and myometrium on survival of patients with endometrial cancer.

Loss of oestrogen receptor (ER) and progesterone receptor (PR) expression in endometrial cancer cells indicates poor prognosis. The aim of this study was to determine the correlation of ER and PR expression in cancer cells and the surrounding myometrium with the disease progression. Immunohistochemical expression of ER and PR was detected in cancer and myometrial cells of patients with EC. ER was detected in 65.2% of cancer cells and in 88.4% of myometrial cells. PR was detected in 59.4% of cancer cells and in 84.1% of myometrial cells. The 5-year overall survival (OS) was 76.8%. Patients with ER and PR negative EC had a shorter period until recurrence (p = .013 and .043) and shorter OS (p = .011 and .066) than those with ER and PR positive cancer. Negative ER and PR status in EC has an impact on recurrence and poor OS. The status of hormone receptors in myometrium may be useful in disease prognosis. Impact Statement The status of hormone receptors in endometrial cancer has been the subject of numerous studies and loss of hormone receptors indicates higher tumor grade and higher clinical stage, lympho-vascular space invasion and deeper myometrial invasion. Although, the communication between the endometrium and myometrium is crucial under physiological conditions, the status of hormone receptors in the myometrium and its significance in cancer progression is poorly studied. Our results showed that loss of ER in the myometrium indicate poor prognosis. The assessment of hormone receptor status in myometrium might be useful in predicting the course of the disease. Results of our research support the theory that stromal and myometrial cells may contribute to tumorigenesis in endometrial cancer. Better understanding of ER/PR expression in myometrial cells is needed, and our research opens new possibilities for identification of key pathways and new potential target molecules in EC prognosis and treatment. It is probable that future classification of endometrial cancer will rely on molecular sub-typing, where the status of hormone receptors in the myometrium might play an important role.

GSK3ß and Gli3 play a role in activation of Hedgehog-Gli pathway in human colon cancer - Targeting GSK3ß downregulates the signaling pathway and reduces cell proliferation.

The role of Hedgehog-Gli (Hh-Gli) signaling in colon cancer tumorigenesis has not yet been completely elucidated. Here we provide strong evidence of Hh-Gli signaling involvement in survival of colon cancer cells, with the main trigger of activation being deregulated GSK3ß. Our clinical data reveals high expression levels of GSK3ß and Gli3 in human colon cancer tissue samples, with positive correlation between GSK3ß expression and DUKES' stage. Further experiments on colon cancer cell lines have shown that a deregulated GSK3ß upregulates Hh-Gli signaling and positively affects colon cancer cell survival. We show that inhibition of GSK3ß with lithium chloride enhances Gli3 processing into its repressor form, consequently downregulating Hh-Gli signaling, reducing cell proliferation and inducing cell death. Analysis of the molecular mechanisms revealed that lithium chloride enhances Gli3-SuFu-GSK3ß complex formation leading to more efficient Gli3 cleavage and Hh-Gli signaling downregulation. This work proposes that activation of the Hh-Gli signaling pathway in colon cancer cells occurs non-canonically via deregulated GSK3ß. Gli3 seems to be the main pathway effector, highlighting the activator potential of this transcription factor, which is highly dependent on GSK3ß function and fine tuning of the Gli3-SuFu-GSK3ß platform.

A correlation between the expression of estrogen receptors and progesterone receptors in cancer cells and in the myometrium and prognostic factors in endometrial cancer.

Endometrial cancer is the most common gynecological malignancy in Croatia. The aim of this study was to determine the immunohistochemical expression of estrogen receptors (ER) and progesterone receptors (PGR) in cancer cells and in the myometrium and to correlate it with prognostic factors of endometrial carcinoma. ER positivity in carcinoma cell nuclei was found in 42 cases (73.7%) and PGR positivity was found in 39 cases (68.4%). Loss of ER in carcinoma cell nuclei correlated with larger tumor size (p = 0.041), poor carcinoma differentiation (p = 0.012), a more aggressive histological type (p < 0.001), lymphovascular space invasion (p = 0.002) and a higher surgical stage (p = 0.037). Loss of PGR in carcinoma cell nuclei correlated with an increased age in patients (p = 0.009), poor tumor differentiation (p = 0.002), a more aggressive histological type (p < 0.001), lymphovascular space invasion (p = 0.002) and a higher surgical stage (p < 0.001). The lower expression of both receptors did not correlate with the depth of myometrial invasion. Regarding the status of receptors in the myometrium, loss of PGR in the myometrium correlated with a more aggressive histological type (p = 0.005) and a lack of ER in the myometrium tended to correlate with tumor growth (p = 0.059). In conclusion, the loss of both hormone receptors in carcinoma cells and loss of PGR in the myometrium was a predictor of a more aggressive type of endometrial cancer and a poor prognosis.

Understanding and Practices of Oral Hygiene in the Intensive Care Units: Perspectives of Medical Staff at Two University Hospital Centers.

Objective: This study assesses the knowledge, practices, and attitudes of medical staff in intensive care units (ICUs) regarding oral hygiene care for critically ill, bedridden patients. Material and methods: A cross-sectional study included 65 employees from the Intensive Care Units of the Sestre Milosrdnice Clinical Hospital Centre (CHC SM) and the Clinic for Anesthesiology and Intensive Care at the University Clinical Hospital Centre Zagreb (CHC ZG). A self-administered questionnaire was used to assess knowledge, methods, frequency, and attitudes towards oral care for mechanically ventilated patients. The data were examined through descriptive statistical methods, presented in terms of proportions (percentages). For the purpose of comparing the feedback across the two hospital centers and different educational backgrounds, the Chi-square and Fisher's exact tests were employed. Results: Results of a survey of 65 participants (18 from CHC SM and 47 from CHC ZG) revealed a notable disparity in oral hygiene knowledge, with graduate nurses displaying the highest proportion of adequate knowledge (100%) and regular nurses showing the least (30.3%) (p<.001). Although the execution of oral care practices did not vary significantly among the groups, graduate nurses performed oral care more frequently (80% vs. baccalaureate technicians 33.33% and nurses 57.6%, three or more times a day) and demonstrated better proficiency in both mechanical (p=.005) and chemical (p<.001) biofilm management compared to their counterparts. No significant difference was observed in the delivery of oral care to orotracheally intubated patients across different educational levels (p=.127). However, a marked difference was noted in the perception of being adequately trained for such care, with nurses feeling less prepared (12.1%, p<.001). Despite these variances, all respondents recognized the importance of oral hygiene, thus showing a strong dedication to oral health care. Conclusions: This study highlights variability in ICU oral hygiene practices and points to the importance of standardized care protocols and improved training for healthcare staff.

Expression and Prognostic Significance of PD-L1 and NY-ESO1 in Gallbladder Carcinoma.

BACKGROUND/AIM: Gallbladder cancer is a rare malignancy with a very high mortality, usually due to diagnosis in an advanced stage of the disease. Therefore, the aim of this study was to evaluate the clinical significance of cancer/testis antigen 1A (CTAG1A, NY-ESO1) and CD274 molecule (PD-L1, the ligand for programmed cell death protein 1) and their impact on the overall survival of patients with gallbladder cancer. PATIENTS AND METHODS: Using immunohistochemical staining, we determined the expression of NY-ESO1 in tumor cells (positivity: cytoplasmic/nuclear staining of any intensity in ≥50%) and PD-L1 in tumor cells and intratumoral immune cells (positivity: cytoplasmic/membranous staining of any intensity in ≥1%). RESULTS: The median overall survival (OS) of 58 patients with gallbladder cancer in our cohort was 7 months, and depended on the clinical stage of the disease; the 5-year OS rate was 10%. NY-ESO1 was expressed in 69.1% of cases. Immune cells were PD-L1-positive in 36.4% of cases, while tumor cells expressed PD-L1 in only 10.9% of cases. In six cases (10.9%), neither of the studied proteins were expressed. NY-ESO1 expression was negatively correlated with PD-L1 expression in immune cells (p=0.021). NY-ESO1 showed no correlation with any clinicopathological parameters or OS. PD-L1 expression in immune cells was significantly higher in tumors with perineural invasion (rs=0.318; p=0.018) and higher clinical disease stage (rs=0.339; p=0.013) but showed no correlation with OS. CONCLUSION: Patients whose gallbladder cancer expresses NY-ESO1 or PD-L1 might be candidates for immunotherapy.

Nuclear localization of NRF2 in stroma of HER2 positive and triple-negative breast cancer.

Breast cancer is one of the leading causes of cancer-related mortality in women. During tumor growth, periods of hypoxia are followed by reoxygenation due to neovascularisation leading to disturbed redox homeostasis. ROS (Reactive Oxygen Species) produced under hypoxia activate HIF1α. ROS can also activate the major antioxidant transcription factor NRF2, but also cause damage to biomolecules. Lipids are susceptible to peroxidation, as evidenced by the formation of reactive aldehydes, among which, HNE (4-hydroxynonenal) is the most studied one. Knowing that HIF1α (Hypoxia Inducing Factor 1α) is associated with breast cancer malignancy, we aimed to investigate its correlation with HNE and NRF2 (Nuclear factor erythroid 2-related factor 2). Our results show that HIF1α is activated in breast cancer, indicating an increase in ROS but not followed by HNE production. On the other hand, NRF2 was increased in all types of breast cancer suggesting that oxidative stress is present in these pathologies, but also supporting HIF1α. Interestingly, NRF2 was activated in HER2 positive and TNBC, indicating the role of stromal NRF2 in breast cancer malignancy.

New characterization and safety evaluation of human limbal stem cells used in clinical application: fidelity of mitotic process and mitotic spindle morphologies.

BACKGROUND: Limbal stem cells (LSCs) are crucial for the regeneration of the corneal epithelium in patients with limbal stem cell deficiency (LSCD). Thus, LSCs during cultivation in vitro should be in highly homogeneous amounts, while potency and expression of stemness without tumorigenesis would be desirable. Therefore, further characterization and safety evaluation of engineered limbal grafts is required to provide safe and high-quality therapeutic applications. METHODS: After in vitro expansion, LSCs undergo laboratory characterization in a single-cell suspension, cell culture, and in limbal grafts before transplantation. Using a clinically applicable protocol, the data collected on LSCs at passage 1 were summarized, including: identity (cell size, morphology); potency (yield, viability, population doubling time, colony-forming efficiency); expression of putative stem cell markers through flow cytometry, immunofluorescence, and immunohistochemistry. Then, mitotic chromosome stability and normal mitotic outcomes were explored by using live-cell imaging. Finally, impurities, bacterial endotoxins and sterility were determined. RESULTS: Expression of the stemness marker p63 in single-cell suspension and in cell culture showed high values by different methods. Limbal grafts showed p63-positive cells (78.7 ± 9.4%), Ki67 proliferation (41.7 ± 15.9%), while CK3 was negative. Impurity with 3T3 feeder cells and endotoxins was minimized. We presented mitotic spindles with a length of 11.40 ± 0.54 m and a spindle width of 8.05 ± 0.55 m as new characterization in LSC culture. Additionally, live-cell imaging of LSCs (n = 873) was performed, and only a small fraction < 2.5% of aberrant interphase cells was observed; 2.12 ± 2.10% of mitotic spindles exhibited a multipolar phenotype during metaphase, and 3.84 ± 3.77% of anaphase cells had a DNA signal present within the spindle midzone, indicating a chromosome bridge or lagging chromosome phenotype. CONCLUSION: This manuscript provides, for the first time, detailed characterization of the parameters of fidelity of the mitotic process and mitotic spindle morphologies of LSCs used in a direct clinical application. Our data show that p63-positive CK3-negative LSCs grown in vitro for clinical purposes undergo mitotic processes with extremely high fidelity, suggesting high karyotype stability. This finding confirms LSCs as a high-quality and safe therapy for eye regeneration in humans.

Prognostic significance of matrix metalloproteinases 2 and 9 in endometrial cancer.

We investigated the prognostic significance of matrix metalloproteinases 2 (MMP 2) and 9 (MMP 9) in endometrial cancer (EC). The expression of MMP 2 and MMP 9 was analyzed immunohistochemically in 73 primary EC patients. In most cases, the gelatinases were predominantly localized to epithelial cell of tumor origin. In univariate analysis histological type, tumor grade, FIGO (1988) surgical stage and high stromal MMP 2 expression were identified as a significant determinant for EC recurrence, while epithelial MMP 2 expression and epithelial and stromal MMP 9 expression were not. Multivariate analysis revealed a subgroup of patient age > or = 63.6 years with endometrioid adenocarcinoma and papillary serous carcinoma, all FIGO (2009) stage I disease where strong staining of stromal MMP 2 increase risk of EC recurrence (p = 0.037).

Primary Ewing's sarcoma of the kidney: a case report.

Primary adult Ewing's sarcoma is a rare entity. They most commonly occur in children and young adults. 6% of them are localized extraosseously. We present a case of a 51 year old patient with primary renal Ewing's sarcoma and multiple metastases in liver and iliac bone. Patients with metastatic disease are usually treated with aggressive chemotherapy and have a poor outcome. Our patient underwent complete surgical excision of tumour, and was treated with aggressive chemotherapy, respectively. Two and half years after presentation he is well, without any symptoms.

Presence of high-risk HPVs, EBV, and MMTV in human triple-negative breast cancer.

Breast cancer, the most frequent disease amongst women worldwide, accounts for the highest cancer-related mortality rate. Triple-negative breast cancer (TNBC) subtype encompasses ~15% of all breast cancers and lack estrogen, progesterone, and HER2 receptors. Although risk factors for breast cancer are well-known, factors underpinning breast cancer onset and progression remain unknown. Recent studies suggest the plausible role of oncoviruses including human papillomaviruses (HPVs), Epstein-Barr virus (EBV), and mouse mammary tumor virus (MMTV) in breast cancer pathogenesis. However, the role of these oncoviruses in TNBC is still unclear. In the current study, we explored the status of high-risk HPVs, EBV, and MMTV in a well-defined TNBC cohort from Croatia in comparison to 16 normal/non TNBC samples (controls) using polymerase chain reaction assay. We found high-risk HPVs and EBV present in 37/70 (53%) and 25/70 (36%) of the cases, respectively. The most common HPV types are 52, 45, 31, 58 and 68. We found 16% of the samples positive for co-presence of high-risk HPVs and EBV. Moreover, our data revealed that 5/70 (7%) samples are positive for MMTV. In addition, only 2/70 (3%) samples had co-presence of HPVs, EBV, and MMTV without any significant association with the clinicopathological variables. While, 6/16 (37.5%) controls were positive for HPV (p = .4), EBV was absent in all controls (0/16, 0%) (p = .01). In addition, we did not find the co-presence of the oncoviruses in the controls (p > .05). Nevertheless, further investigations are essential to understand the underlying mechanisms of multiple-oncogenic viruses' interaction in breast carcinogenesis, especially TNBC.

DNA and cytogenetic damage in white blood cells of postmenopausal breast cancer patients treated with radiotherapy.

The primary and residual genome damage and its elimination rate were evaluated in peripheral blood lymphocytes of breast cancer patients treated with adjuvant radiotherapy after surgical removal of the tumor by mastectomy or quadrantectomy. The levels of DNA/chromosome damage were estimated before, throughout, as well as after six months, respectively one year after the radiotherapy, using the alkaline comet assay, the chromosome aberration analysis and the cytokinesis-block micronucleus assay. The marked individual differences in the baseline genome damage were observed in patients, which additionally increased until the end of the radiotherapy cycle. The levels of DNA/cytogenetic damage slowly declined during post-irradiation period; although in the majority of subjects they did not return to pre-therapy levels. In addition to the well-established comet parameters, the long-tailed nuclei were also proved as a useful indicator of individual DNA damage and response to radiation. One of the most important observation was that older breast cancer patients, irradiated after mastectomy, had higher values of almost all parameters evaluated. We found positive correlations between the comet assay parameters and the cytogenetic biomarkers that confirmed their complementary value in the assessment of the radiation sensitivity/susceptibility in elderly breast cancer patients. The specific patterns of DNA damage observed in the majority of subjects after a prolonged exposure to ionizing radiation indicate the possibility of adaptive response. Such results may also be linked to the hormesis theory and support previous observations, but the underlying mechanisms should be further investigated on a much larger population.

Cytogenetic follow-up in testicular seminoma patients exposed to adjuvant radiotherapy.

Early stage testicular seminoma is a radiosensitive tumor. Its incidence has significantly increased during the last decade especially in the young population. Although the therapy for testicular seminoma gives very satisfying results, the evaluation of genome damage caused by the therapy is of a great importance in order to recognize possible related health risks. The present study was performed on ten patients diagnosed with seminoma stage I; pT1/2N0M0S0, treated with adjuvant radiotherapy (a radiation dose of 25 Gy divided in 16 fractions) after orchidectomy. To assess the possible existence of an increased baseline DNA/chromosome damage in patients we also selected the appropriate control group often healthy men. The levels of primary DNA/chromosome damage in peripheral blood lymphocytes, as well as the dynamics of their repair were studied using the alkaline comet assay, chromosome aberration and cytokinesis-block micronucleus assay. Altogether four blood samples per patient were collected in the course of the therapy: before and after receiving the first dose of radiotherapy, in the middle of the radiotherapy cycle, and after the last dose of radiotherapy. Other two follow-up blood samples were collected six and twelve months after the cessation of therapy. As observed, the administration of the first radiation dose significantly increased the levels of DNA damage in almost all patients compared to their baseline values. Specific patterns of DNA damage were recorded in samples analyzed in the middle of radiotherapy and after receiving the last dose, indicating the possibility of an adaptive response in some patients. The levels of chromosomal aberrations and the incidence of micronuclei also increased in the course of therapy but gradually declined during the follow-up period. Our results confirmed the existence of post-irradiation damage in peripheral blood lymphocytes (and possibly in other non-target cells) of cancer patients which may represent a risk for the secondary cancer development. Considering that the majority of patients with testicular cancer are of a younger age, they represent a population deserving special attention. As cytogenetic screening may detect high-risk individuals, it might be useful in regular medical monitoring of seminoma patients after the successful therapy.

Evaluation of radioprotective effects of propolis and its flavonoid constituents: in vitro study on human white blood cells.

This in vitro study aimed to evaluate the possible radioprotective effects of the natural substances WSDP, caffeic acid, chrysin and naringin on gamma-irradiated human white blood cells. The effectiveness of tested compounds was evaluated using the alkaline comet assay, the analysis of structural chromosome aberration and the cytokinesis-block micronucleus assay. The results obtained by the alkaline comet study indicate favourable toxicity profiles of propolis and its polyphenolic components, and confirmed the radioprotective abilities comparable to the chemical radioprotector AET. WSDP and its polyphenolic components were able to reduce the number of necrotic cells. None of tested compounds induced significant genotoxicity, but all of them offered a quite measurable protection against DNA damage. WSDP was found to be the most effective in diminishing the levels of primary and more complex cytogenetic DNA damage in white blood cells. Considering its complex composition, to undoubtedly explain the underlying mechanisms of cyto/radioprotective effects, further studies are needed.

Chromosome Missegregation and Aneuploidy Induction in Human Peripheral Blood Lymphocytes In vitro by Low Concentrations of Chlorpyrifos, Imidacloprid and α-Cypermethrin.

Chlorpyrifos, imidacloprid, and α-cypermethrin are some of the most widely used insecticides in contemporary agriculture. However, their low-dose, nontarget genotoxic effects have not been extensively assayed. As one of the most relevant cancer biomarkers, we aimed to assess the aneuploidy due to chromosome missegregation during mitosis. To aim it we treated human lymphocytes in vitro with three concentrations of insecticides equivalents relevant for real scenario exposure assessed by regulatory agencies. We focused on chlorpyrifos as conventional and imidacloprid and α-cypermethrin as sustainable use insecticides. Cytokinesis-blocked micronucleus assay was performed coupled with fluorescence in situ hybridization (FISH) with directly labeled pancentromeric probes for chromosomes 9, 18, X and Y. None of the insecticides induced significant secondary DNA damage in terms of micronuclei (MN), nuclear buds (NB), or nucleoplasmic bridges (NPB). However, significant disbalances in chromosomes 9, 18, X and Y, and in insecticide-treated cells has been observed. According to recent studies, these disbalances in chromosome numbers may be atributted to defect sister chromatid cohesion which contribute to the increase of chromosome missegregation but not to micronuclei incidence. We conclude that tested insecticidal active substances exert chromosome missegregation effects at low concentrations, possibly by mechanism of sister chromatid cohesion. These findings may contribute to future risk assesments and understanding of insecticide mode of action on human genome. Environ. Mol. Mutagen. 60:72-84, 2019. © 2018 Wiley Periodicals, Inc.

Genome damage in oropharyngeal cancer patients treated by radiotherapy.

AIM: To estimate genome damage in oropharyngeal cancer patients before, during, and after radiotherapy and to measure the persistence of caused genome damage relevant in the evaluation of secondary cancer risk. METHODS: DNA damage was evaluated in peripheral blood lymphocytes of 10 oropharyngeal cancer patients using alkaline comet assay, analysis of structural chromosome aberrations, and micronucleus assay. Blood samples were taken 2 hours before irradiation on day 1 of the first radiotherapy cycle, 2 hours after the application of the first dose, in the middle of the radiotherapy cycle, within 2 hours after the last received radiotherapy dose, and after 6 and 12 months after radiotherapy. RESULTS: In most participants, the highest level of primary DNA damage was recorded in blood samples collected after the administration of first radiation dose (mean tail length 25.04+/-6.23 mum). Most patients also had increased frequency of comets with long tail-nucleus (LTN comets) after the administration of the first radiation dose (mean, 10.50+/-7.71 per 100 comets), which remained increased in the middle of radiotherapy (mean, 18.30+/-27.62 per 100 comets). Later on, the levels of primary DNA damage as recorded by the comet assay, slightly diminished. The frequency of structural chromosome aberrations in lymphocytes gradually increased during the radiation cycle (26.50+/-27.72 per 100 metaphases at the end of the therapy), as well as the frequency of micronuclei (mean total number of micronuclei 167.20+/-35.69 per 1000 binuclear cells). CONCLUSION: Oropharyngeal cancer patients had relatively high levels of primary DNA damage in their peripheral blood lymphocytes even before therapy. The frequency of complex structural chromosome aberrations and the frequency of micronuclei increased with the progression of the radiation cycle and the doses delivered. As the frequency of chromosomal aberrations a year after radiotherapy mostly did not return to pre-therapy values, it represents an important risk factor related to the onset of second cancer.

Irinotecan toxicity to human blood cells in vitro: relationship between various biomarkers.

Toxic effects of the antineoplastic drug irinotecan on human blood cells at concentrations of 9.0 microg/ml and 4.6 microg/ml were evaluated in vitro. Using the alkaline and neutral comet assay significantly increased levels of primary DNA damage in lymphocytes were detected. The induction of apoptosis/necrosis, as determined by a fluorescent assay, was also notably increased. Cytogenetic outcomes of the treatment were assessed by the analysis of structural chromosome aberrations and fluorescence in situ hybridization. A significantly higher incidence of chromatid breaks and complex quadriradials was observed. Painted chromosomes 1, 2 and 4 were equally involved in translocations, but only the chromosome 1 was involved in the formation of quadriradials. Sister chromatid exchange analysis was performed in parallel with the analysis of lymphocyte proliferation kinetics. The higher concentration of irinotecan caused almost seven-time increase, while the lower one caused a five-time increase of the basal sister chromatid exchange frequency, accompanied with significant lowering of the lymphocyte proliferation index. Using the cytokinesis-block micronucleus assay, a dose-dependent increase in micronucleus frequency along with the formation of nuclear buds and nucleoplasmic bridges was noticed. Inhibitory effects of irinotecan on enzyme acetylcholinesterase (AChE) were studied in erythrocytes. An IC(50) value of 5.0 x 10(-7) was established. Irinotecan was found to be strong inhibitor of the acetylcholine hydrolysis and to cause a continuous decrease of catalytic activity of AChE. The results obtained on a single donor may contribute to the understanding of irinotecan toxicity, but further in vitro and in vivo studies are essential in order to clarify remaining issues, especially on possible inter-individual variability in genotoxic responses to the drug.