Role of cytoblock on pleural effusion for diagnosis of malignant disease

BACKGROUND

Thoracocentesis of pleural effusion is a simple technique for pleural fluid examination through cytology. In addition to cytological examination to assess the nature of pleural fluid content, we can also perform more detailed examinations through cytoblocks of residual fluid. These paraffin-embedded cytoblock samples are important because we can perform examinations as in other bioptic samples. In these samples, immunohistochemical and molecular analyses can be performed.

METHODS

Two hundred fifty-five cytological samples from patients with pleural effusion were examined. In cases in which the presence of malignant cells was identified in the cytological examination, as well as cases that were suspicious but not definitive for the presence of a malignant effusion, a cytoblock was prepared. Histological examination and immunohistochemical analysis were performed.

RESULTS

Among 255 cases with pleural effusion, 152 had the presence of malignant cells and 6 cases were suspicious, but uncertain for the presence of malignant cells, while 86 cases had inflammatory pleural effusion or other pathologies but were not malignant. After histological analysis of the cytoblock and immunohistochemical analysis, we identified 82 malignant tumors of the lung, 8 malignant tumors of the gastrointestinal tract, 15 malignant tumors of the breast, and 6 malignant tumors of the female genital tract, as well as 24 tumors of undetermined origin.

CONCLUSIONS

Cytoblocks are important for the diagnosis of the primary nature of malignant pleural effusions. The highest importance is primary lung tumors, as well as those tumors in which the primary site of the tumor cannot be determined clinically.

AB0097 EFFECT OF CYTOCHROME P450 METABOLITES OF ARACHIDONIC ACID IN RHEUMATOID ARTHRITIS

Background

Arachidonic acid (AA) is a polyunsaturated fatty acid, released in inflammatory disease, such as rheumatoid arthritis (RA). Cyclooxygenase (COX) and lypooxygenase (LOX) pathways have received greater attention than cytochrome P450 (CYP) pathway of AA, which also plays a significant role in RA. AA is a substrate of CYP enzymes through two different pathways: the ω-hydroxylase, and epoxygenase pathways, respectively. The epoxygenase gives rise to epoxyeicosatrienoic acids (EETs) (5,6-EET, 8,9-EET, 11,12-EET, 14,15-EET), whereas ω- hydroxylase produces hydroxyeicosatetraenoic acids (HETEs) [1].

Objectives

The aim of this study is to evaluate the role of Cytochrome P450 metabolites of arachidonic acid and their therapeutic targeting in rheumatoid arthritis.

Methods

Pubmed and Scopus databases were the main databases used to identify all the studies conformed to the eligibility criteria.

Results

CYP enzymes (CYP3A, CYP2C19, CYP2C9, CYP1A2) suppression was observed in the synovial fluid of RA patients with higher IL-6 levels. EETs inhibit bone resorption and osteoclastogenesis, have an important role in blocking inflammation by reducing TNFα, and are negatively linked with pro-inflammatory cytokines (IL-1, IL-6, IL-8)[2]. The anti-inflammatory effects of EETs are potentially attributed to peroxisome proliferator–activated receptor gamma (PPARγ) activation. EETs are also metabolized through soluble epoxide hydrolase (sEH) to dihydroxyeicsatrienoic acids (DHETs), which have a pro-inflammatory activity. On the other hand, 20-HETE deriving from CYP ω-hydroxylase pathway has pro-inflammatory effect [3]. Data have shown that the genetic variations of CYP could affect the individual susceptibility to RA [4].

Conclusion

sEH inhibitors (sEHi) can not only block the inflammation caused by EETs metabolite, but can also act on LOX and COX pathway, and can be used in chronic-phase arthritis to reduce both inflammation, and the pain. In a mouse model of RA, sEHi showed decent RA assessment score improvement [5]. Moreover, data suggest that sEHi inhibit also PGE2 production, and exert an additional anti-inflammatory effect in arthritis. Since NSAIDs can lead to gastric and cardiovascular problems, sEHi are considered a better pharmacological approach in inflammatory rheumatic disease. Despite the failure of some of sEHi to reach clinical trials, we believe that CYP-derived eicosanoids should be further studied as potential target in rheumatic disease. Dual inhibitors sEHI/5-LOX activating protein (FLAP) are also very promising compounds as they can inhibit leukotriene formation, without effecting the levels of anti-inflammatory pro-resolving mediators. In perspective we suggest that multiple ligands targeting different AA pathways or mediators should be further explored as potential targets for designing new compounds to treat RA patients.

References

[1]M. Hoxha, B. Zappacosta. CYP-derived eicosanoids: Implications for rheumatoid arthritis. Prostaglandins Other Lipid Mediat. 146 (2020) 106405.

[2]X. Xu, X.A. Zhang, D.W. Wang, The roles of CYP450 epoxygenases and metabolites, epoxyeicosatrienoic acids, in cardiovascular and malignant diseases, Adv. Drug Deliv. Rev. 63 (8) (2011) 597–609.

[3]D. Panigrahy, A. Kaipainen, E.R. Greene, S. Huang, Cytochrome P450-derived eicosanoids: the neglected pathway in cancer, Cancer Metastasis Rev. 29 (4) (2010) 723–735

[4]S. Puntarulo, A.I. Cederbaum, Production of reactive oxygen species by microsomes enriched in specific human cytochrome P450 enzymes, Free Radic. Biol. Med. 24 (7–8) (1998) 1324–1330

[5]J. Park, M.J. Cho, H.J. Park, Analgesic effects of soluble epoxide hydrolase inhibitor in K/BxN serum transfer arthritis mouse model, Anesth. Pain Med. 14 (2019) 76–94.

Disclosure of Interests

None declared

A case-control study: Evaluating the role of leukotriene receptor antagonists in preventing the cardiovascular and cerebrovascular disease

INTRODUCTION

Leukotriene receptor antagonists (LTRAs) are used as a therapeutic alternative in asthmatic patients. Different animal studies indicate that LTRAs can decrease intimal hyperplasia after vascular injury, and have a protective role in cerebral ischemia.

OBJECTIVE

The aim of this study was to assess the role of leukotriene receptor antagonists in preventing the cardiovascular and ischemic stroke in humans.

MATERIAL AND METHOD

A matched case-control study with a follow up period of three years has been conducted, investigating the effect of the LTRAs in the myocardial infarct (MI) risk, and in the ischemic stroke (IS) risk in asthmatic patients from San Cecilio University Hospital of Granada, and from two Primary Health Care Centers of Granada.

RESULTS

59 cases with MI and 108 cases with IS were included in the study, each of them with an equal number of controls matched by age and sex in each of the two Health Care Centers. Unlike for MI risk, the treatment with LTRAs was associated with a slight trend in reducing the risk of stroke, in both of the primary care controls (Odds ratios: 0.74 (0.37-1.47); 0.82 (0.4-1.67), for the first, and the second Health Centers Controls, respectively), but without reaching a statistical significance.

CONCLUSIONS

The results did not confirm a protective effect of LTRAs on cardiovascular risk as suggested by different animal studies.

Risk of renal cell carcinoma in relation to blood telomere length in a population-based case-control study

Background:

There are few known risk factors for renal cell carcinoma (RCC). Two small hospital-based case–control studies suggested an association between short blood telomere length (TL) and increased RCC risk.

Methods:

We conducted a large population-based case–control study in two metropolitan regions of the United States comparing relative TL in DNA derived from peripheral blood samples from 891 RCC cases and 894 controls. Odds ratios and 95% confidence intervals were estimated using unconditional logistic regression in both unadjusted and adjusted models.

Results:

Median TL was 0.85 for both cases and controls (P=0.40), and no differences in RCC risk by quartiles of TL were observed. Results of analyses stratified by age, sex, race, tumour stage, and time from RCC diagnosis to blood collection were similarly null. In multivariate analyses among controls, increasing age and history of hypertension were associated with shorter TL (P<0.001 and P=0.07, respectively), and African Americans had longer TL than Caucasians (P<0.001).

Conclusion:

These data do not support the hypothesis that blood TL is associated with RCC. This population-based case–control study is, to our knowledge, the largest investigation to date of TL and RCC.

Allergy, asthma and markers of infections among Albanian migrants to Southern Italy

BACKGROUND

Studies of immigrants represent an useful tool to determine the relative relevance of environmental vs genetic factors in causing the reported rapid increase of the prevalence of sensitization and allergic diseases.

METHODS

A total of 152 Albanian migrants to Southern Italy responded to a questionnaire based on the European Community Respiratory Health Survey (ECRHS) and 139 of them underwent skin prick test, and 61 serological assays for total IgE and IgG antibodies against Toxoplasma gondii (TG), herpes simplex virus 1 (HSV-1), hepatitis A virus (HAV) and Helicobacter pylori (HP).

RESULTS

Reported asthma was rare (2/152; 1.3%) and reported nasal allergies rather frequent (24/152; 15.8%). Sensitization to common inhalant allergens occurred in 27/139 (19.4%) subjects. The frequency of skin sensitization to pollen (P = 0.003) and that of hay fever (P = 0.004) increased with the time spent in Apulia. All the 61 sera had antibodies against HAV, 59/61 (96.7%) against HSV-1, 48/61 (78.7%) against HP and 34/61 (55.7%) against TG. The prevalence of skin sensitization and hay fever symptoms were correlated to the duration of residence in Southern Italy.

CONCLUSIONS

Data presented indicate that Albanian migrants to Italy, in spite of the low prevalence of allergic diseases and sensitization in their country of origin, manifest with time an increasing prevalence of sensitization to local allergens and nasal symptoms after immigration to Italy. This would suggest a permanent role of allergen exposure and lifestyle factors in influencing the appearance of sensitization and symptoms of allergic diseases.

Dap (Defective aleurone pigmentation) mutations affect maize aleurone development

Dap (Defective aleurone pigmentation) is the designation for mutations in maize that give rise to a characteristic dappled endosperm phenotype, consisting of patches of purple tissue, of variable size and shape, on a yellow background. Features shared by all Dap mutants are: dominant expression when they are maternally derived, lack of expression or transmission when they originate from pollen, failure to recover homozygous Dap genotypes, reduced frequency of Dap seeds in the progeny of outcrosses of Dap/+ females, association of the dappled phenotype with reduction in seed size. The mutants so far tested, six in all, can be grouped into two classes, one including male-transmissible (MT) isolates not expressed in the endosperm if their contribution is paternal, and a second class of isolates (NMT) that are permanently lost following paternal transmission. We suggest that the NMT mutations are on a chromosome that carries an intercalary deletion. Assuming linkage between the mutant and the deletion, selection against the deficient chromosome during male gametogenesis would account for the failure to recover Dap seeds in the progeny of Dap/+ male parents. We have obtained genetic evidence supporting this hypothesis. This interpretation, however, does not apply to MT alleles. For these, other mechanisms, such as imprinting and/or dosage effects may be proposed. The mutable pattern in the endosperm to which all Dap mutants give rise is an intriguing phenotype which remains to be clarified. An unexpected finding is that aleuronic and subaleuronic cells corresponding to the colourless areas are abnormal in shape and anthocyanin biosynthesis is blocked in these cells. This finding calls for further investigation in light of a possible connection between flavonoid precursors and cell shape.