Investigation of the potential of miRNA candidates as non-invasive biomarkers for the diagnosis and follow-up of colorectal cancer.

BACKGROUND: Colorectal cancer (CRC) is the third most common cancer worldwide, and despite advances in treatment, molecular biomarkers are needed for both early diagnosis and prognosis monitoring. It is known that microRNAs (miRNA), one of the epigenetic mechanisms, are effective in the initiation and development of cancer by regulating the activity of tumor suppressors and/or oncogenes. In this study, the potential of the molecules let-7, miRNA125b, and miRNA30a, which are known to play a role in cellular processes, as biomarkers for colorectal cancer and their molecular mechanisms were investigated in this model. The aim was to evaluate the diagnostic, prognostic, and predictive utility of the target miRNAs in colorectal cancer patients. MATERIAL AND METHODS: The expression changes of miRNAs let-7, miRNA125b, and miRNA30a were investigated by miRNAs isolation and cDNA synthesis from the serum samples of 60 patients diagnosed with CRC or from the serum samples of 20 healthy individuals. The calculation was performed using the quantitative real-time polymerase chain reaction method to determine the expression level. The results were compared with clinical parameters. RESULT: An 8-fold decrease in the expression of let-7 and miRNA125b and a 60-fold decrease in the expression of miRNA30a were found in the serum samples of patients diagnosed with colorectal cancer (CRC) compared to the healthy group. A decrease in let-7 was observed in 53.3%, miRNA125b in 58.3%, and miRNA30a in 55% of patients. A significant correlation was found between the reduced expression status and the stage, lymph nodes, local recurrence, and metastasis (p < 0.05). The ROC analysis showed that the miRNA30a level could be a diagnostic biomarker for CRC (p < 0.001). No significant impact of target miRNA expression changes on overall disease survival was observed. CONCLUSION: It is thought that the target miRNA30a can be used for early diagnosis and screening and that the target miRNA let-7, miRNA125b, and miRNA30a can be used as non-invasive biomarkers for disease follow-up, with larger patient studies being conducted on CRC patients.

Serum folate and vitamin B12 levels in cutaneous melanoma.

BACKGROUND: Vitamin B12 and folate are the major micronutrients that play significant roles in DNA synthesis. Epidemiological studies and clinical evidences displayed alterations in serum concentrations folate and of vitamin B12 in various human malignancies, yet their roles in patients with melanoma have yet to be understood. OBJECTIVE: To assess circulating vitamin B12 and folate concentrations of patients with melanoma and compare them with other malignant tumors and healthy subjects. METHODS: A total of 98 skin melanoma cases from university clinic were enrolled into the study. Serum vitamin B12 and folate concentrations were analyzed by electrochemiluminescence binding assay. RESULTS: Circulating levels of vitamin B12 in patients with melanoma were similar compared with other malignancies and healthy controls (P > .05). However, melanoma cases had significantly lower serum folate concentrations than healthy control group (P = .04). Melanoma patients with metastatic disease (P = .001) and with short history of disease (P = .05), and those who had active diseases in course of the study (P = .04) had low serum folate concentrations. CONCLUSION: Serum levels of folate were found significantly lower in melanoma cases, and this association was stronger for patients with metastatic melanoma; however, no such association was found between melanoma and serum vitamin B12 levels.

Effect of intraperitoneal cetuximab administration on colonic anastomosis and early postoperative adhesion formation in a rat model.

OBJECTIVE: We aimed to evaluate the effect of intraperitoneal cetuximab administration on the healing of anastomosis and development of early adhesion formation in a rat model. MATERIALS AND METHODS: Twenty-four female rats were used. A colon segment was resected and end-to-end anastomosis was performed. The rats were randomized into three groups after the performance of colonic anastomosis and received 10 mL of intraperitoneal solution including study drugs after closure of abdominal cavity: normal saline was administered to the normal saline group (n=8), cetuximab (400 mg/m(2)) was administered to the postoperative 1 group (n=8) 1 day after surgery, and cetuximab (400 mg/m(2)) was administered to the peroperative group (n=8) during surgery. RESULTS: The mean adhesion grade was 2.63±0.92, and 0.50±0.76 and 0.63±0.74 for control and test groups, respectively. Cetuximab reduced adhesion formation in test groups (p<0.05). When all groups were compared, it was found that vascular endothelial growth factor levels decreased significantly only in the abdomen (p<0.05). Hydroxyproline levels and anastomosis bursting pressure were examined, and a statistical difference was found between groups (hydroxyproline p<0.05, bursting pressure p<0.05). However, when postoperative 1 day group was compared with the control group, it was found that there was no difference between groups according to these parameters (p>0.05), but when peroperative group was compared with the control group a significant decrease was observed in both parameters. Histopathological healing score was also evaluated. No statistical difference between groups was found. CONCLUSION: Twenty-four hours later from the operation, intraperitoneal cetuximab therapy may be a safe and feasible treatment for metastatic colorectal patients.

Circulating serum levels of angiopoietin-1 and angiopoietin-2 in nasopharynx and larynx carcinoma patients.

We aimed to determine the serum levels of angiogenic factors, namely angiopoietins, in nasopharyngeal and laryngeal carcinoma patients. We also aimed to seek the relation of these molecules with tumor grade and their utility as diagnostic biomarkers. We evaluated angiopoietin 1 and 2 levels innasopharynx and larynx cancer patients before treatment. Angiopoietin 2 levels were significantly elevated in larynx carcinoma patients and tended to be elevated in nasopharynx cancer patients compared with healthy controls. However, angiopoietin 1 levels were similar in cancer patients and controls. Angiopoietin 1 levels were significantly higher in nasopharyngeal cancer patients with advanced stages compared to earlier stages. On the other hand, angiopoietin 2 levels were similar in advanced and earlier stage cancer patients.

For which cancer types can neuron-specific enolase be clinically helpful in Turkish patients?

BACKGROUND: The aim of the present study was to evaluate the serum neuron-specific enolase (NSE) levels in patients with prostate cancer, Hodgkin lymphoma, lung cancer and peripheral nerve tumors. MATERIALS AND METHODS: NSE levels were determined by ELISA in the sera of 100 prostate cancer, 47 Hodgkin lymphoma, 35 lung cancer and 35 peripheral nerve tumor patients and also in 132 healthy controls. RESULTS: The median levels of serum NSE were elevated in patients with lung cancer (p=0.018) and peripheral nerve tumors (p=0.008). NSE levels in prostate cancer and Hodgkin lymphoma patients were higher than the controls but there was no statistically significant difference (p>0.05). CONCLUSIONS: We conclude that NSE may be applied in routine to gain insight about the clinical statuses of various cancer patients, but more studies are needed to determine the organ specificity.

Effects of intraperitoneal bevacizumab administration on colonic anastomosis and early postoperative adhesion formation.

AIM: The purpose of this study is to investigate the effect of intraperitoneal (IP) bevacizumab on colonic anastomosis and evaluate the effects on early postoperative adhesion formation. MATERIALS AND METHODS: A total of 24 mature female Sprague-Dawley rats were used for this study. Rats were randomly assigned to a control group that received saline (n = 8) or to experimental groups (n = 8 each) that received bevacizumab at a dose of 2.5 mg/kg (group 1) or 5 mg/kg (group 2). Animals were killed humanely on the seventh day after operation, and measurements of anastomotic strength and biochemical variables were performed. RESULTS: The mean adhesion grade was 2.63 ± 0.92, and 1 ± 0.93 and 0.75 ± 0.71 for the control and test groups, respectively. Bevacizumab significantly reduced adhesion formation in both low-dose and high-dose IP applications (P < .05). When all groups were compared, it was found that VEGF levels decreased significantly only in the tissue (P = .001), whereas there was no significant difference in the blood and the IP fluid (P = .73 and .08, respectively). We evaluated hydroxyproline levels, anastomosis bursting pressure, and histopathological healing scores. When each of these parameters were examined, there was statistical difference between groups (P = .01, .004, and .01, respectively). It was found that these parameters significantly decreased depending on increasing drug dose. CONCLUSION: IP administration of bevacizumab effectively reduced the formation of adhesions and caused significant impairment of anastomotic wound healing when standard doses were administered (5 mg/kg), but the 2.5-mg/kg dosage did not affect the anastomotic wound healing and also effectively reduced the formation of adhesions.

Markers of bone metastases in breast and lung cancers.

AIM AND BACKGROUND: The aim of the present study was to evaluate correlations between serum osteocalcin, osteoprotegerin and NTX (Cross-linked N-telopeptides of Type I Collagen) and urinary NTX in breast and lung cancer patients with bone metastases. These four markers are considered to have important roles in bone formation, resorption and metastases. METHODS: Four markers were determined in the sera of 60 breast cancer and 21 lung cancer patients and healthy controls (n=30). Serum levels were studied using ELISA and EIA. RESULTS: The median levels of serum osteoprotegerin (p<0.001) and osteocalcin (p=0.003) were higher in patients. Significant correlations were observed between the serum NTX-osteocalcin (r=0.431; p<0.001), serum NTX- osteoprotegerin (r=0.42; p=0.003) and serum NTX - urine NTX (r=0.255; p=0.022). CONCLUSION: We conclude that osteocalcin, osteoprotegerin and NTX are independent diagnostic tools. Due to the ease of urine collection, urine NTX may be applied routinely to allow early detection of bone metastases and indicate progression of the disease.

Utility of serum and urine uPAR levels for diagnosis of breast cancer.

Malignant tumors have a capacity to degrade the extracellular matrix by controlled proteolysis. One system involved in these processes is the urokinase-type plasminogen activator (uPA) system. uPAR levels are elevated in tumors from several types of cancer. Our study was planned to investigate serum and urine levels of uPAR in breast cancer patients (n=180) and healthy controls (n=60) by ELISA. Serum (p<0.001) and urine (p<0.001) uPAR values in the patients were both significantly elevated. High serum and urine levels of uPAR can be used as diagnostic tools in lymph node positive patients.

Lack of diagnostic potential of Dickkopf-1 in colon and rectum cancers.

The Wnt/b-catenin signalling pathway plays crucial roles in development and its aberrant activation is an initial and crucial event in the majority of colon cancers. The Dickkopf-1 (Dkk-1) gene encodes an extracellular Wnt inhibitor that blocks the formation of signalling receptor complexes at the plasma membrane. Here, we report the serum levels of Dkk1 in colorectal cancer patients without any therapy. The levels were determined by enzyme-linked immunosorbent assay (ELISA) in 135 colon and 160 rectum cancer patients, as well as 90 healthy subjects. Data analyses were performed using SPSS software (SPSS 16, Chicago, IL). There were no significant differences among the groups for Dkk-1 (p=0.363). In conclusion, the present study did not confirm that serum Dkk-1 levels could have any diagnostic potential in colon and rectum cancers.

Variations in systemic biomarkers of oxidative/nitrosative stress and DNA damage before and during the consequent two cycles of chemotherapy in breast cancer patients.

BACKGROUND: Previous studies have suggested the importance of redox regulation in carcinogenesis. The aim of this study was to evaluate the prognostic role of altered redox homeostasis and oxidative DNA damage in patients with breast carcinoma before and during two cycles of chemotherapy. METHODS: This study included 30 patients whose serum samples were obtained on admission before treatment, and after the first and second cycles of chemotherapy, and 20 controls. We investigated serum total antioxidant status (TAS), thiobarbituric acid reacting substances (TBARS), total nitrite/nitrate (NOx), nitrotyrosine (NT), and 8-hydroxydeoxy-guanosine (8-OHdG), as well as antioxidant enzyme activities, such as glutathione peroxidase (GPx), glutathione reductase (GRx). RESULTS: TBARS, NOx, NT and 8-OHdG concentrations were significantly increased, while antioxidant enzyme activities and TAS were significantly decreased in patients when compared to controls. A concurrent increase in TBARS, NOx, NT, and 8-OHdG and a decrease in antioxidant enzyme activities and TAS were also seen after chemotherapy. No difference was observed in the second cycle of chemotherapy when compared with the first course. CONCLUSIONS: In conclusion, decreased activities of these antioxidant enzymes and low TAS concentrations observed in our study might be due to the depletion of the antioxidant defense system to combat the free radical storm produced by chemotherapy. We suggest that the increased 8-OHdG and other oxidative/nitrosative stress products that we have measured in breast cancer patients may be prognostic risk factors for the magnitude of oxidation in serum.

Serum levels of interleukin-6 and interleukin-10 in Turkish patients with aggressive non-Hodgkin's lymphoma.

There exists strong evidence that tumor growth can be actively controlled by the host immune system and interleukins are known to play a significant role in immune response regulation. Inflammatory cytokines play important roles in the pathogenesis of lymphomas. This study was conducted to investigate the serum levels of IL-6 and IL-10 in patients with aggressive non-Hodgkin's lymphoma (A-NHL) and the relationships with prognostic parameters and therapy. These serum factors were measured in 46 A-NHL patients pathologically verified before and after chemotherapy in comparison with 21 healthy controls using enzyme-linked immunosorbent assays (ELISAs). There were significant differences in the serum IL-10 and IL-6 levels between A-NHL patients and controls (p= 0.038 and p<0.001, respectively). None of the prognostic parameters analyzed was significantly correlated with the serum IL-6 concentrations. This was also true for serum IL-10 values, except for LDH and bone marrow involvement. Serum IL-10 levels were elevated in the group of patients with high level LDH compared with the group of patients with a normal level (p= 0.017). Also, serum IL-10 levels were significantly different in the presence or absence of bone marrow involvement (p= 0.016). In addition, we found a significant relationship between the serum levels of serum levels of IL-6 and IL-10 in patients with A-NHL (r= 0.47, p<0.001). We found that serum IL-10 levels decreased due to chemotherapy effect independent of the chemotherapy response (p= 0.027). However, serum IL-6 levels were not changed. In conclusion, our data suggest that higher serum IL-6 and IL-10 levels can be useful for diagnosis of A-NHL. However, our sample size is small, and larger scale research is needed in this field to provide new knowledge.

Serum levels of angiogenic factors in early breast cancer remain close to normal.

The study which we performed was to determine serum concentrations of angiogenic factors including VEGF, angiogenin and TGF-beta 1 in early stage breast cancer patients. These parameters were measured by ELISA in sera of 90 patients with breast cancer and 75 healthy controls. The mean serum VEGF concentration in patients compared to controls was not significantly different (0.33ng/mL vs 0.43ng/mL, respectively; p=0.156). Likewise, the insignificant change in mean values in patients vs controls was also observed for serum TGF-beta 1 (0.19ng/mL vs 0.19ng/mL, respectively; p=0.215) and serum angiogenin (243.24ng/mL vs 244.5ng/mL, respectively; p=0.976). Statistically significant correlation was found only between the tests, such as VEGF and angiogenin in patients who were included in the study (p<0.001). In conclusion, we couldn't find any diagnostic value between the early stage breast cancer and the three angiogenic parameters.

Serum levels of intercellular adhesion molecule ICAM-1 and E-selectin in advanced stage non-small cell lung cancer.

Cell adhesion is a basic count in inter- and intra-cellular communication and plays an important role in tumor progression. This study was conducted to investigate the serum levels of intercellular adhesion molecule (ICAM-1) and E-selectin in patients with advanced stage non-small cell lung cancer (NSCLC) and the relationships with known prognostic parameters and therapy. These serum factors were measured of 57 NSCLC patients pathologically verified before and after chemotherapy in comparison with 24 healthy controls by using ELISA method. Serum levels of ICAM-1 were increased significantly in NSCLC patients compared with the healthy controls (P = 0.006). However, serum E-selectin levels were not significantly different from healthy control groups (0.643). No statistically significant relationships were found between investigated all serum parameters and various characteristics of patients, and the diseases such as stage and tumor burden. Likewise, we also found no correlation between serum ICAM-1 and E-selectin (P = 0.78). We found that serum ICAM-1 levels were decreased owing to the chemotherapy effect, independently from chemotherapy response. However, serum E-selectin levels were not changed by the chemotherapy effect. The median survival of all patients was 11.9 months and 1-year survival rate was 47.6%. We found that patients performance status (P = 0.013), age (P = 0.015), and weight loss (P = 0.007) were prognostic factors for survival. Serum E-selectin levels showed a trend (P = 0.08) related to worse prognosis, however serum ICAM-1 levels were determined as ineffective on survival (P = 0.11). Multivariate analysis revealed that only weight loss (P = 0.005) and E-selectin levels (P = 0.002) remained as an independent prognostic factor for survival in patients with advanced NSCLC. In conclusion, our data suggest that higher serum ICAM-1 can be useful for diagnosis while E-selectin levels have prognostic significance and could be a potential prognostic factor in NSCLC patients.

Serum levels of apoptosis biomarkers, survivin and TNF-alpha in nonsmall cell lung cancer.

CONTEXT: This study was conducted to investigate the prognostic role and the effects of chemotherapy on serum apoptosis biomarkers consisting of survivin and tumor necrosis factor alpha (TNF-alpha) in patients with advanced stage nonsmall cell lung cancer (NSCLC). MATERIALS AND METHODS: Fifty-seven patients with newly diagnosed NSCLC were enrolled into study. Performance status was 0 or 1 in 47 patients and 2 in 10 patients. Thirty-two of them were no or less than 10% weight loss. Patients were treated with platinum-based chemotherapy. Serum levels of TNF-alpha and survivin were determined by enzyme-linked immunosorbent assay (ELISA) technique. RESULTS: While serum survivin levels in patients were not significantly different from controls (p=0.321), serum TNF-alpha levels in patients were found significantly higher than in controls (p=0.029). We found that serum TNF-alpha levels were increased (p<0.001), whereas serum levels of survivin (p=0.025) were decreased by the chemotherapy effects. The changes of the TNF-alpha and survivin serum levels due to chemotherapy effect showed a significant negative correlation (r=-0.36 p=0.007). The increase of serum TNF-alpha levels was independent from chemotherapy response; however, the reduction of serum survivin levels was found only significant in the chemoresponsive group (p=0.039). While older age, weight loss and performance status yielded prognostic value, neither TNF-alpha nor survivin levels proved to be significant for survival. CONCLUSION: Our findings suggest that the reduction in the serum survivin levels of advanced NSCLC patients after chemotherapy can be used as a predictor of response to the chemotherapy but not that of survival.

Serum IL-8 and IL-12 levels in breast cancer.

Interleukins (ILs) are known to play a fundamental role in cancer. We investigated the serum levels of IL-8 and IL-12, in breast cancer patients, and their relationship with the prognostic parameters and therapy. Forty eight patients with pathologically verified breast carcinoma and 21 healthy controls were enrolled into the study. Serum samples were obtained at baseline and after two cycles of chemotherapy. Serum IL-8 and IL-12 levels were determined using enzyme-linked immunosorbent assay (ELISA). There was no significant difference in the baseline serum IL-8 and IL-12 levels between breast cancer patients and healthy controls (p = 0.365 and p = 0.871, respectively), no significant correlation between the prognostic parameters and the serum IL-8, IL-12 levels. However, in the subgroup consisting of metastatic breast cancer patients, baseline serum IL-8 levels were significantly higher compared with non-metastatic disease (p = 0.047). Anthracycline-based chemotherapy and the addition of taxane did not change the levels of both serum IL-8 and IL-12. Serum IL-8 level may be useful in determining metastatic breast cancer. Larger studies are needed to confirm this finding.