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Analysis of blood and lymphatic vessel in colorectal cancer is controversial in the literature, possibly due to variations in the methods of analysis. In this study, it was aimed to search for a reliable approach in the quantification of angio- and lymphangiovascular density and area as a prognostic factor and to compare such vessel counts in normal mucosa, adenomas and cancer. A retrospective study was performed on 60 sporadic colorectal cancer, 30 colorectal adenomas, and 10 colorectal non-neoplastic lesions. Archival tissues were submitted to immunohistochemical evaluation using antibodies to CD31, CD34, CD105, VEGF-A, VEGF-C, and D2-40. Microvessel density and total vascular area were determined by computer image analysis and values were compared in the three groups of lesions; the prognostic value of these parameters was evaluated in the group of colorectal cancer. Most markers showed progressive vessel counts from non-neoplastic tissue to carcinoma, both for microvessel density and total vascular area. Only microvessel density determined by CD34 in the central areas of the cancer correlated with recurrence/metastasis (p = 0.04) and survival (p = 0.02). Different methods of quantification (microvessel counting versus estimation of total vascular area), immunohistochemical markers (pan-endothelial marker versus neovessels and lymphatic markers), and areas of analysis (periphery versus inner portions of the lesion) were assessed using image analysis. The results corroborate the increase in vascularization of carcinoma and suggest that microvessel density determined by immunostaining for CD34 in the inner portion of the tumor might represent a prognostically relevant parameter in colorectal cancer.

Background: Asian rust (Phakopsora pachyrhizi) is a common disease in Brazilian soybean fields and it is difficult to control. To identify a biochemical candidate with potential to combat this disease, a new chitinase-like xylanase inhibitor protein (XIP) from coffee (Coffea arabica) (CaclXIP) leaves was cloned into the pGAPZα-B vector for expression in Pichia pastoris., Results: A cDNA encoding a chitinase-like xylanase inhibitor protein (XIP) from coffee (Coffea arabica) (CaclXIP), was isolated from leaves. The amino acid sequence predicts a (β/α)8 topology common to Class III Chitinases (glycoside hydrolase family 18 proteins; GH18), and shares similarity with other GH18 members, although it lacks the glutamic acid residue essential for catalysis, which is replaced by glutamine. CaclXIP was expressed as a recombinant protein in Pichia pastoris. Enzymatic assay showed that purified recombinant CaclXIP had only residual chitinolytic activity. However, it inhibited xylanases from Acrophialophora nainiana by approx. 60% when present at 12:1 (w/w) enzyme:inhibitor ratio. Additionally, CaclXIP at 1.5 μg/μL inhibited the germination of spores of Phakopsora pachyrhizi by 45%., Conclusions: Our data suggests that CaclXIP belongs to a class of naturally inactive chitinases that have evolved to act in plant cell defence as xylanase inhibitors. Its role on inhibiting germination of fungal spores makes it an eligible candidate gene for the control of Asian rust.

Blood and lymphatic vessel proliferation is essential for tumor growth and progression. Most colorectal carcinomas develop from adenomas (adenoma-carcinoma sequence) in a process due to accumulation of molecular genetic alterations. About 5% of adenomatous polyps are expected to become malignant, but data on the differential angiogenic patterns of these lesions in patients with and without concomitant cancer are missing. The aim of the present study is to compare the angiogenic and lymphatic patterns of adenomatous polyps from patients with and without sporadic cancer. Thirty adenomatous polyps (15 from patients with another principal malignant lesion, and 15 from patients without cancer) were submitted to immunohistochemical staining for CD105 (marker for neoangiogenesis) and D2-40 (marker for lymphatic endothelium). Microvessel density and total vascular area were determined by computer image analysis to quantify the immunostained and total areas, and to assess the number of microvessels. Adenomas from patients with carcinoma showed significantly higher values of total vascular area determined by immunostaining for CD105 (cutoff value = 4386 microm(2); P = 0.019) and of lymphatic microvessel density determined by immunostaining with D2-40 (cutoff value = 11.5; P = 0.041) when compared with those from patients without cancer. The present data indicate a significant increase in blood microvascular area and in lymphatic microvascular counts in adenomas removed from patients with cancer.

5-Fluorouracil (5-FU) represents the basis of chemotherapy for colorectal carcinoma, inhibiting thymidylate synthase (TS), an essential enzyme for DNA replication. Previous studies have associated high TS protein expression by tumor cells with poor outcome of patients with colorectal carcinoma, but others have refuted these findings. In view of the potential role of TS as predictive parameter and the lack of consensus in the literature, the present study compared 2 methods: protein expression and gene polymorphism, correlating them with clinicopathological findings. Immunohistochemical detection of TS in tumor cells and detection of gene polymorphism in the blood were performed in 32 patients with colorectal carcinoma treated with 5-FU. No correlation was found between TS protein expression and gene polymorphism. Neither method correlated with survival, tumor staging, and tumor histological grading. This result possibly reflects a complex tumor response to 5-FU therapy, where TS is just one of the involved proteins.

Human haptoglobin is classified into three major phenotypes: Hp1-1, Hp2-1 and Hp2-2; there are two autosomal alleles Hp*1 and Hp*2, and the Hp*1 allele has two subtypes, Hp*1F and Hp*1S. Haptoglobin acts as an antioxidant, preventing hemoglobin-driven oxidative damage. We used the comet assay to examine oxidative damage to DNA induced by hydrogen peroxide in human leukocytes; we also looked for differences in the antioxidant capacity of haptoglobin subtypes. Haptoglobin genotypes were determined through allele-specific polymerase chain reaction, visualized on a polyacrylamide gel. The Hp1-1 genotype had the least DNA damage; this indicates that Hp alleles differ in their protective effects against oxidative damage. Among Hp*1 alleles, Hp*1F was the most protective.

Context: The presence of multiple neoplasms in one patient is an uncommon event. Its occurrence ranges from 1.2% to 4.5% of cancer patients in autopsy and clinical studies. In the present article, cases of synchronous diagnoses of carcinoma and lymphoid neoplasms are reported. The intention of this report was to alert clinicians and pathologists to the possibility of the existence of concomitant neoplasms, in order to prevent inaccurate or delayed diagnosis and staging., Cases: Seven patients (four female and three male) with a median age of 61.4 years were diagnosed as having concomitant epithelial and hematological neoplasms., Discussion and Conclusion: Lymph nodes should be carefully examined when searching for metastases, because of the possibility of a second hematological malignancy. Whenever uncommon suspicious morphological features are seen in such neoplasms, an immunohistochemical analysis is essential.

Hemicellulose is a complex group of heterogeneous polymers and represents one of the major sources of renewable organic matter. Mannan is one of the major constituent groups of hemicellulose in the wall of higher plants. It comprises linear or branched polymers derived from sugars such as D-mannose, D-galactose, and D-glucose. The principal component of softwood hemicellulose is glucomannan. Structural studies revealed that the galactosyl side chain hydrogen interacts to the mannan backbone intramolecularly and provides structural stability. Differences in the distribution of D-galactosyl units along the mannan structure are found in galactomannans from different sources. Acetyl groups were identified and distributed irregularly in glucomannan. Some of the mannosyl units of galactoglucomannan are partially substituted by O-acetyl groups. Some unusual structures are found in the mannan family from seaweed, showing a complex system of sulfated structure. Endohydrolases and exohydrolases are involved in the breakdown of the mannan backbone to oligosaccharides or fermentable sugars. The main-chain mannan-degrading enzymes include beta-mannanase, beta-glucosidase, and beta-mannosidase. Additional enzymes such as acetyl mannan esterase and alpha-galactosidase are required to remove side-chain substituents that are attached at various points on mannan, creating more sites for subsequent enzymatic hydrolysis. Mannan-degrading enzymes have found applications in the pharmaceutical, food, feed, and pulp and paper industries. This review reports the structure of mannans and some biochemical properties and applications of mannan-degrading enzymes.

Objective: It is controversial whether age is associated with higher grade and worse outcome. Some studies have not found age to be related to outcome nor younger age to be associated with better response to therapy., Materials and Methods: The study population consisted of 27 patients aged 55 years or younger and 173 patients 56 years or older submitted to radical prostatectomy. The variables studied were preoperative PSA, time to PSA progression following radical prostatectomy and pathologic findings in surgical specimens: Gleason score, Gleason predominant grade, positive surgical margins, tumor extent, extraprostatic extension (pT3a), and seminal vesicle invasion (pT3b)., Results: Comparing patients aged 55 years or younger and 56 years or older, there was no statistically significant difference for all variables studied: preoperative PSA (p = 0.4417), Gleason score (p = 0.3934), Gleason predominant grade (p = 0.2653), tumor extent (p = 0.1190), positive surgical margins (p = 0.8335), extraprostatic extension (p = 0.3447) and seminal vesicle invasion (p > 0.9999). During the study period, 44 patients (22%) developed PSA progression. No difference was found in the time to biochemical progression between men aged 55 years or younger and 56 years or older., Conclusions: Our findings suggest that age alone do not influence the biological aggressiveness of prostate cancer.