3-nitrotyrosine and Colorectal-Neoplasms

Colorectal cancer as well as colorectal surgery is associated with increased oxidative stress through different mechanisms. In this study the levels of different oxidative stress markers were comparatively assessed in patients who underwent laparoscopic or conventional resection for colorectal cancer.. Sixty patients with colorectal cancer were randomly assigned to undergo laparoscopic (LS) or open surgery (OS). Lipid, protein, RNA, and nitrogen damage was investigated by measuring serum 8-isoprostanes (8-epiPGF2α), protein carbonyls (PC), 8-hydroxyguanosine (8-OHG), and 3-nitrotyrosine (3-NT), respectively. The primary end point of the study was to analyze and compare serum levels of the oxidative stress markers between the groups.. Postoperative serum levels of 8-epiPGF2α, 3-NT, and 8-OHG were significantly lower in the LS group at 24 h after surgery (p < 0.05). At 6 h postoperatively, the levels of 8-epiPGF2α and 3-NT were significantly lower in the LS group (p < 0.05). No difference in the levels of PC was found between the two groups at any time point. In the OS group, postoperative levels of 8-epiPGF2α were significantly lower than the preoperative values (p < 0.01). In the LS group, the postoperative values of 8-epiPGF2α, 3-NT, and 8-OHG were significantly lower than the preoperative values (p < 0.05).. Laparoscopic surgery for colorectal cancer is associated with lower oxidative stress compared to open surgery. 8-epiPGF2α was the most suitable marker for readily defining the oxidative status in patients who underwent surgery for colorectal cancer.

Topics: Aged; Analysis of Variance; Biomarkers; Colectomy; Colorectal Neoplasms; Dinoprost; Double-Blind Method; Female; Guanosine; Humans; Laparoscopy; Male; Oxidative Stress; Postoperative Period; Protein Carbonylation; Tyrosine

Quantification with satisfactory specificity and sensitivity of free 3-Nitro-l-tyrosine (3-NT), 3-Chloro-l-tyrosine (3-CT), and 3-Bromo-l-tyrosine (3-BT) in biological samples as potential inflammation, oxidative stress, and cancer biomarkers is analytically challenging. We aimed at developing a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based method for their simultaneous analysis without an extract purification step by solid-phase extraction. Validation of the developed method yielded the following limits of detection (LOD) and quantification (LOQ) for 3-NT, 3-BT, and 3-CT: 0.030, 0.026, 0.030 ng/mL (LODs) and 0.100, 0.096, 0.098 ng/mL (LOQs). Coefficients of variation for all metabolites and tested concentrations were <10% and accuracy was within 95-105%. Method applicability was tested on colorectal cancer patients during the perioperative period. All metabolites were significantly higher in cancer patients than healthy controls. The 3-NT was significantly lower in advanced cancer and 3-BT showed a similar tendency. Dynamics of 3-BT in the early postoperative period were affected by type of surgery and presence of surgical site infections. In conclusion, a sensitive and specific LC-MS/MS method for simultaneous quantification of free 3-NT, 3-BT, and 3-CT in human plasma has been developed.

Topics: Aged; Biomarkers; Chromatography, Liquid; Colorectal Neoplasms; Female; Humans; Inflammation; Male; Metabolomics; Middle Aged; Nitrosative Stress; Oxidative Stress; Postoperative Complications; Postoperative Period; Prospective Studies; Reactive Oxygen Species; Reproducibility of Results; Sensitivity and Specificity; Surgical Wound Infection; Tandem Mass Spectrometry; Tyrosine

Colorectal laterally spreading tumors (LSTs) are morphologically subdivided into granular (LST-G) and nongranular (LST-NG) categories. We aimed to elucidate the differences in oncogenic characteristics between the two types.. Laterally spreading tumors resected by endoscopic submucosal dissection and surgery from March 2009 to May 2017 were examined for p53 positivity, Ki-67 labeling index (LI), microvessel density, degree of fibrosis, intensities of inducible nitric oxide synthase (iNOS) and nitrotyrosine (NT), and expression of acid mucins. We compared these factors between adenomas, noninvasive cancers, and invasive cancers, both LST-G and LST-NG.. Ninety-three LST-G (53 adenomas [LST-GA] and 40 cancers [LST-GC]) and 55 LST-NG (24 adenomas [LST-NGA] and 31 cancers [LST-NGC]) were evaluated. Although p53 positivity was lower in LST-GA than in LST-NGA (P < 0.001), there was no difference between LST-GC and LST-NGC. Ki-67 LI was higher in LST-NGA than in LST-GA (P < 0.001) and higher in LST-NGC than in LST-GC of noninvasive cancers (P < 0.001). Microvessel density and degree of fibrosis were higher in LST-NGA than in LST-GA (P < 0.001), and intensities of iNOS and NT were also higher in LST-NGA than in LST-GA (P < 0.001). Expression of acid mucins was lower in LST-NGA than in LST-GA (P < 0.001). Although there were significant differences in p53 positivity, Ki-67 LI, microvessel density, degree of fibrosis, intensities of iNOS and NT, and expression of acid mucins between LST-GA and LST-NGA, these factors were only slightly different between LST-GC and LST-NGC of invasive cancers.. Unlike LST-GA, LST-NGA possessed phenotypic features similar to cancer.

Topics: Adenoma; Carcinogenesis; Cohort Studies; Colorectal Neoplasms; Fibrosis; Humans; Intestinal Mucosa; Ki-67 Antigen; Microvessels; Mucins; Neoplasm Invasiveness; Nitric Oxide Synthase Type II; Phenotype; Retrospective Studies; Tumor Suppressor Protein p53; Tyrosine

3-Nitrotyrosine (3-NT), a product of peroxynitrite reaction, is abundantly observed in hepatocytes adjacent to human metastatic colorectal carcinoma. To elucidate its biological significance, we undertook to identify nitric oxide (NO)-producing cells and apoptosis under oxidative stress. We observed strong inducible NO-synthase (iNOS) immunoreactivity in the hepatocytes adjacent to metastatic tumor, revealing an identical pattern to 3-NT immunostaining. Furthermore, intense 3-NT immunostaining of hepatocytes was associated with apoptosis whereas carcinoma cells near those hepatocytes presented high proliferating-cell nuclear antigen. Our results suggest that contact of metastatic tumor induces apoptosis in adjacent hepatocytes through peroxynitrite, thus permitting the proliferation of cancer cells.

Topics: Adenocarcinoma; Aged; Apoptosis; Cell Division; Colorectal Neoplasms; Female; Humans; Immunoenzyme Techniques; Liver Neoplasms; Male; Middle Aged; Nitrates; Nitric Oxide; Nitric Oxide Synthase; Nitric Oxide Synthase Type II; Oxidants; Oxidative Stress; Proliferating Cell Nuclear Antigen; Reactive Oxygen Species; Tyrosine