Glutathione level and glutathione-dependent enzyme activities in blood serum of patients with gastrointestinal tract tumors

Human protozoa infection and dysplasia in ulcerative colitis: a neglected aspect in a prominent disease

The chance of getting colorectal cancer (CRC) is higher in people with chronic ulcerative colitis (UC). The impact of parasitic infections on UC is underappreciated. The purpose of this study was to look into the effect of intestinal protozoal infections on the dysplastic changes generated by UC. The research included 152 adult patients with histologically confirmed UC and 152 healthy controls. Fecal samples were examined for the presence of parasites and fecal calprotectin (FC). The enzyme-linked immunosorbent assay measured serum anti-p53 antibodies (p53Abs) and metallothioneins (MTs). The advanced oxidation protein products (AOPPs) and reduced glutathione (GSH) levels were measured by a spectrophotometric method in all subjects. Serum C-reactive protein (CRP) and IL-6 were also measured. In addition, histopathological and immunohistochemical investigations of intestinal tissue were done. Our results exhibited significant increases in FC and CRP, IL-6, AOPPs, MTs, and p53Abs in ulcerative colitis patients with parasitic infections compared to those without parasites. In contrast, GSH levels showed a significant decrease in the same group compared with other groups. Histopathological and immunohistochemical assessments of intestinal tissue signified severe inflammation and strong expression of PD-L1 in patients with parasitic infections compared to others without parasitic infections. Our research indicated a greater frequency of intestinal protozoa in UC patients with elevated inflammatory and dysplastic biomarker levels. This suggests that these parasites may be involved in the etiology of chronic UC and the associated carcinogenetic process. This is the first report of a link between parasitic infections and dysplastic alterations in UC patients.

MnO2 nanoparticles decorated with Ag/Au nanotags for label-based SERS determination of cellular glutathione

A novel stimulus-responsive surface-enhanced Raman scattering (SERS) nanoprobe has been developed for sensitive glutathione (GSH) detection based on manganese dioxide (MnO₂) core and silver/gold nanoparticles (Ag/Au NPs). The MnO₂ core is not only capable to act as a scaffold to amplify the SERS signal via producing "hot spots", but also can be degraded in the presence of the target and thus greatly enhance the nanoprobe sensitivity for sensing of GSH. This approach enables a wide linear range from 1 to 100 µM with a 2.95 µM (3σ/m) detection limit. Moreover, the developed SERS nanoprobe represents great possibility in both sensitive detection of intracellular GSH and even can monitor the change of intracellular GSH level when the stimulant occurs. This sensing system not merely offers a novel strategy for sensitive sensing of GSH, but also provides a new avenue for other biomolecules detection.

A non-canonical sensing pathway mediates Plasmodium adaptation to amino acid deficiency

Eukaryotes have canonical pathways for responding to amino acid (AA) availability. Under AA-limiting conditions, the TOR complex is repressed, whereas the sensor kinase GCN2 is activated. While these pathways have been highly conserved throughout evolution, malaria parasites are a rare exception. Despite auxotrophic for most AA, Plasmodium does not have either a TOR complex nor the GCN2-downstream transcription factors. While Ile starvation has been shown to trigger eIF2α phosphorylation and a hibernation-like response, the overall mechanisms mediating detection and response to AA fluctuation in the absence of such pathways has remained elusive. Here we show that Plasmodium parasites rely on an efficient sensing pathway to respond to AA fluctuations. A phenotypic screen of kinase knockout mutant parasites identified nek4, eIK1 and eIK2-the last two clustering with the eukaryotic eIF2α kinases-as critical for Plasmodium to sense and respond to distinct AA-limiting conditions. Such AA-sensing pathway is temporally regulated at distinct life cycle stages, allowing parasites to actively fine-tune replication and development in response to AA availability. Collectively, our data disclose a set of heterogeneous responses to AA depletion in malaria parasites, mediated by a complex mechanism that is critical for modulating parasite growth and survival.

Selective Inhibition of Cysteine-Dependent Enzymes by Bioorthogonal Tethering

A general approach for the rapid and selective inhibition of enzymes in cells using a common tool compound would be of great value for research and therapeutic development. We previously reported a chemogenetic strategy that addresses this challenge for kinases, relying on bioorthogonal tethering of a pan inhibitor to a target kinase through a genetically encoded non-canonical amino acid. However, pan inhibitors are not available for many enzyme classes. Here, we expand the scope of the chemogenetic strategy to cysteine-dependent enzymes by bioorthogonal tethering of electrophilic warheads. For proof of concept, selective inhibition of two E2 ubiquitin-conjugating enzymes, UBE2L3 and UBE2D1, was demonstrated in biochemical assays. Further development and optimization of this approach should enable its use in cells as well as with other cysteine-dependent enzymes, facilitating the investigation of their cellular function and validation as therapeutic targets.

Plasma Total Antioxidant Capacity and Carbonylated Proteins Are Increased in Pregnant Women with Severe COVID-19

Oxidative stress (OS) induced by SARS-CoV-2 infection may play an important role in COVID-19 complications. However, information on oxidative damage in pregnant women with COVID-19 is limited. Objective: We aimed to compare lipid and protein oxidative damage and total antioxidant capacity (TAC) between pregnant women with severe and non-severe COVID-19. Methods: We studied a consecutive prospective cohort of patients admitted to the obstetrics emergency department. All women positive for SARS-CoV-2 infection by reverse transcription-polymerase chain reaction (RT-qPCR) were included. Clinical data were collected and blood samples were obtained at hospital admission. Plasma OS markers, malondialdehyde (MDA), carbonylated proteins (CP), and TAC; angiogenic markers, fms-like tyrosine kinase-1 (sFlt-1) and placental growth factor (PlGF); and renin-angiotensin system (RAS) markers, angiotensin-converting enzyme 2 (ACE-2) and angiotensin-II (ANG-II) were measured. Correlation between OS, angiogenic, and RAS was evaluated. Results: In total, 57 pregnant women with COVID-19 were included, 17 (28.9%) of which had severe COVID-19; there were 3 (5.30%) maternal deaths. Pregnant women with severe COVID-19 had higher levels of carbonylated proteins (5782 pmol vs. 6651 pmol; p = 0.024) and total antioxidant capacity (40.1 pmol vs. 56.1 pmol; p = 0.001) than women with non-severe COVID-19. TAC was negatively correlated with ANG-II (p < 0.0001) and MDA levels (p < 0.0001) and positively with the sFlt-1/PlGF ratio (p = 0.027). Conclusions: In pregnant women, severe COVID-19 is associated with an increase in protein oxidative damage and total antioxidant capacity as a possible counterregulatory mechanism.

Oxidative and Antioxidative Status Expressed as OSI Index and GSH/GSSG Ratio in Children with Bone Tumors after Anticancer Therapy Completion

Aims. There are no data on the redox status of children with bone tumors in complete disease remission. Therefore, the presented study examined the reduced/oxidized glutathione (GSH/GSSG) ratio, total oxidant capacity (TOC) and total antioxidant capacity (TAC) values as well as the oxidative stress index (OSI) for assessing alterations in the oxidant/antioxidant balance in 35 children with osteosarcoma or Ewing’s sarcoma after anticancer therapy completion (median 14 months) compared with a control group. Methods. GSH, GSSG, TOC, TAC concentrations and bone alkaline phosphatase (BALP) activity were evaluated by immunoenzymatic (ELISA) and enzymatic methods. Results. We found no differences in serum BALP activity between all survivors with bone tumors and the control group. Patients with osteosarcoma after anticancer therapy completion had significantly higher values of TAC, GSH and the GSH/GSSG ratio as well as GSSG than healthy subjects. In patients with Ewing’s sarcoma, we found significantly higher values of TOC concentration compared with healthy children. In addition, survivors with Ewing’s sarcoma had higher TOC concentrations and OSI index values (p < 0.01), but a lower GSH/GSSG ratio (p < 0.05) than survivors with osteosarcoma. A positive correlation between TOC and the post-therapy period was observed in survivors. Conclusions. We found that in survivors with bone tumors, a disturbed balance between prooxidants and antioxidants persists after the completion of anticancer treatment. Moreover, an increased TOC value together with the post-therapy period may suggest increasing oxidative processes in survivors with bone tumors after treatment. Further observations will allow assessment of the relationship between the oxidant/antioxidant status and the predisposition of survivors to bone neoplastic disease recurrence.

Highly selective and sensitive detection of glutathione over cysteine and homocysteine with a turn-on fluorescent biosensor based on cysteamine-stabilized CdTe quantum dots

In this work, cysteamine (CA) stabilized CdTe quantum dots (QDs) (CA-CdTe QDs) and sodium citrate stabilized gold nanoparticles (AuNPs) were prepared. Because of the strong electrostatic interaction and spectral overlap of emission spectrum of CA-CdTe QDs and absorption spectrum of AuNPs, a highly effective fluorescence resonance energy transfer (FRET) system was formed and the fluorescence of CA-CdTe QDs was strongly quenched. The synthesized CA-CdTe and AuNPs were self-assembled to large clusters due to the electrostatic attraction and the fluorescence of CA-CdTe was sharply quenched as a result of FRET. Under the optimum pH of 5.5, the positive GSH could assemble with negative AuNPs through electrostatic interaction and destroy the FRET system of CA-CdTe and AuNPs, due to the red shift of absorption wavelength of AuNPs caused by aggregation. The fluorescence of CA-CdTe recovered, and the recovered fluorescence efficiency shows a linear function against the GSH concentrations from 6.7 nM to 0.40 μM, with a detecting limit of 3.3 nM. The quenched emission of CA-CdTe could be recovered attributed to the aggregation of AuNPs by GSH. Under optimal conditions, the sensing system was successfully applied in the detection of GSH in real human blood plasma samples with a recovery of 99.5-102.3%, showing a promising future for the highly sensitive and selective GSH detection in the human blood plasma samples.

Sensitive detection of glutathione through inhibiting quenching of copper nanoclusters fluorescence

A method for a sensitive fluorescence detection of glutathione was established. Glutathione-stabilized copper nanoclusters (CuNCs) were synthesized via a facile process. These CuNCs showed blue fluorescence with a peak around 450 nm. In the presence of p-benzoquinone (PBQ), the electron transfer from the copper nanoclusters to PBQ quenched the fluorescence of the CuNCs. Glutathione (GSH), as a reducing agent, formed a complex with PBQ. This formation inhibited the quenching from PBQ, and a restored fluorescence was obtained. This interaction provided a fluorescence enhancement for the measurement of GSH. Under the optimal condition, linear responses were obtained toward GSH in the ranges of 0.06-6.0 μM, with a limit of detection at 20 nM. This developed assay was easy in operation with high sensitivity and selectivity. The applicability was approved with successful glutathione measurements in real samples.

Supramolecular grafting of stimuli-responsive, carrier-free, self-deliverable nanoparticles of camptothecin and antisense DNA for combination cancer therapy

A supramolecular approach for the crafting of self-deliverable nanoparticles of antisense DNA and camptothecin for combination cancer therapy is reported.

Increased Oxidative Stress in Gastric Cancer Patients and Their First-Degree Relatives: A Prospective Study from Northeastern Brazil

Background and Aims

First-degree relatives of gastric cancer patients are at increased risk of developing gastric cancer. Increased oxidative stress, including lipid peroxidation, has been associated with gastric carcinogenesis. Whether first-degree relatives of gastric cancer patients have increased oxidative stress remains unknown. We aimed to compare oxidative stress in patients with gastric cancer, their first-degree relatives, and dyspeptic controls.

Methods

A total of 155 patients undergoing upper endoscopy were prospectively enrolled, including 50 with gastric cancer, 49 first-degree relatives of gastric cancer patients, and 56 controls. Serum concentrations of malondialdehyde (MDA) and glutathione) and activities of superoxide dismutase (SOD) and catalase were measured. Multivariate analysis adjusting for sex, age, smoking status, and alcohol consumption was performed.

Results

Lipid peroxidation, as measured by concentration of MDA (nmol/mL), was higher (p = 0.04), and glutathione levels were lower (p < 0.001) in the gastric cancer group compared to controls. There was no difference in the catalase activity among the groups. There was no difference in glutathione and MDA concentration or catalase activity between the different stages of gastric cancer based on the TNM classification. Relatives of gastric cancer patients had higher glutathione concentration (μmol/mL) compared to gastric cancer patients (262.5 vs. 144.6; p = 0.018), while there was no difference in MDA concentration. Catalase and superoxide dismutase activity were lower in the gastric cancer group (3.82 vs. 0.91; p < 0.001 and 1.04 vs. 0.6; p < 0.001) compared to their first-degree relatives. Interestingly, MDA concentration in the first-degree relative group was higher than in the control group (7.9 vs. 5.1; p = 0.03).

Conclusions

In this study, similarly to gastric cancer patients, their first-degree relatives were found to have increased oxidative stress compared to controls. Further studies are warranted to validate this observation and to better understand the role of oxidative stress as a possible biomarker in this population.

Superoxide dismutase and the sigma1 receptor as key elements of the antioxidant system in human gastrointestinal tract cancers

This long-term research was designed to evaluate whether superoxide dismutase (SOD) isoenzymes participate in the development of human gastrointestinal neoplasms and the potential influence of the sigma1 receptor (Sig1R) on the regulation of SOD gene expression during the neoplastic process. The experiments included human tissues from selected gastrointestinal tract tumors (liver cancer, colorectal adenocarcinoma, and colorectal cancer liver metastases). Activity, protein levels, and mRNA levels were determined for SOD isoenzymes and Sig1R. Additionally, markers of oxidative stress (glutathione, lipid peroxidation) were measured. The results showed significant changes in the antioxidant system activity in all examined types of tumors. SOD changed both in healthy cells and in neoplastic cells. The activity and expression of all studied enzymes significantly changed due to the advancement of tumor development. The Sig1R might be an additional regulator of the antioxidant system on which activity might depend on the survival and proliferation of cancer cells. Overall, the study shows that SOD1 and SOD2 are involved not only in the formation of neoplastic changes in the human gastrointestinal tissues (healthy intestine - colon tumor; healthy liver - liver cirrhosis - liver cancer) but also in the development of tumors in the sequence: benign tumor - malignant tumor - metastasis.

The Effectiveness of Glutathione Redox Status as a Possible Tumor Marker in Colorectal Cancer

The role of oxidative stress (OS) in cancer is a matter of great interest due to the implication of reactive oxygen species (ROS) and their oxidation products in the initiation of tumorigenesis, its progression, and metastatic dissemination. Great efforts have been made to identify the mechanisms of ROS-induced carcinogenesis; however, the validation of OS byproducts as potential tumor markers (TMs) remains to be established. This interventional study included a total of 80 colorectal cancer (CRC) patients and 60 controls. By measuring reduced glutathione (GSH), its oxidized form (GSSG), and the glutathione redox state in terms of the GSSG/GSH ratio in the serum of CRC patients, we identified significant changes as compared to healthy subjects. These findings are compatible with the effectiveness of glutathione as a TM. The thiol redox state showed a significant increase towards oxidation in the CRC group and correlated significantly with both the tumor state and the clinical evolution. The sensitivity and specificity of serum glutathione levels are far above those of the classical TMs CEA and CA19.9. We conclude that the GSSG/GSH ratio is a simple assay which could be validated as a novel clinical TM for the diagnosis and monitoring of CRC.

Glutathione-related antioxidant defense system in patients with hypertensive retinopathy

Objective: To analyze the glutathione antioxidant defense system changes in the tear and serum of patients with hypertensive retinopathy (HR) and to establish whether there is an interdependence between their levels and HR degree.

Methods: 90 patients were split into three groups according to the Keith-Wagner-Barker grading of HR: GI–36 patients; GII–35 patients; GIII–19 patients. The concentration of reduced glutathione (GSH) and activities of glutathione peroxidase (GPx) and glutathione reductase (GR) in tear and serum were measured. Results were analyzed by ANOVA, followed by Bonferroni post hoc test. The Spearman correlation coefficient was calculated (p≤0.05 statistically significant).

Results: In serum, the GSH level and GPx activity were not statistically changed between groups with HR degree advancement, unlike the GR activity that was statistically diminished (p=0.018). The values of the studied markers in the tear showed a decrease with the progression of the HR degree. Only serum GSH level correlated with the tear one (r=-0.361, p=0.000), while the enzymes activity did not. A correlation of GPx and GR activity (r=0.417, p=0.000) was identified in tear, while in serum - of GPx activity and GSH level (r=409, p=0.000). Tear GPx and GR levels correlated significantly but with low power with HR degree (r=0.299, p=0.004/ r=0.299, p=0.004).

Conclusion: Statistically significant elevation in tear GPx and GR activity and a tendency of GSH level increase was revealed, being attested, and a direct correlation between GPx and GR activity, as well as of their activity with the HR degree. In serum, the GSH level and the GPx activity did not change accurately, while the GR activity diminished significantly, the identified decrease being correlated with the HR degree.

Abbreviations: HR = hypertensive retinopathy, HTN = hypertension, GSH = reduced glutathione, GPx = glutathione peroxidase, GR = glutathione reductase, GGR = gamma-glutamyl transferase, ROSs = reactive species of oxygen, OS = oxidative stress

Enhanced peroxidase-like activity of Fe3O4-sodium lignosulfonate loaded copper peroxide composites for colorimetric detection of H2O2 and glutathione

In this paper, the composites of Fe₃O₄ modified by sodium lignosulfonate and copper peroxide (Fe₃O₄@CP) were produced by a simple two-step method, and their morphology and composition were featured in Field emission scanning electron microscopy, X-ray powder diffraction, X-ray diffraction and Fourier transform infrared. Then, Fe₃O₄@CP catalyzed the oxidation of colorless 3,3',5,5'-tetramethylbenzidine to blue oxide in the presence of H₂O₂, indicating that it had good catalytic performance. Further, the experimental conditions were optimized, including time, pH, temperature and material concentration. The kinetic analysis results showed that Fe₃O₄@CP exhibited excellent catalytic performance and its catalytic kinetic plot conformed to the Michaelis-Menten equation and the catalytic mechanism was consistent with the ping-pong mechanism. Finally, a H₂O₂ colorimetric assay with a linear range of 0.2-300 μM and a detection limit of 0.11 μM was constructed. In addition, due to the decolorization reaction of ox-TMB with glutathione and the scavenging effect of GSH on hydroxyl radicals (·OH), a glutathione colorimetric assay was further constructed with a linear range of 0.2-40 μM and a detection limit of 0.05 μM. It also verified that the assay had excellent selectivity and stability and could be utilized to detect actual samples.

Oxidant/Antioxidant Status of Breast Cancer Patients in Pre- and Post-Operative Periods

Background and Objectives: The purpose of this study is to evaluate the level of oxidative stress before and after breast cancer surgery. Materials and Methods: Malondialdehyde (MDA) level was tested using a thiobarbituric acid (TBA) assay based on the release of a color complex due to TBA reaction with MDA. The glutathione S-transferase (GST) activity was evaluated by enzymatic conjugation of reduced glutathione (GSH) with 1-chloro-2,4-dinitrobenzene. The level of total glutathione (reduced GSH and oxidized GSSG) was detected using a recycling system by 5,5-dithiobis(2-nitrobenzoic acid). The levels of the indices were determined in the serum of 52 patients before surgery, two hours and five days after surgery, and in 42 healthy women. Results: In the patients over 50 years old the level of MDA was higher after surgery in comparison with before surgery, and GST activity was lower in comparison with the control. The GSH + GSSG level in both ages groups after surgery was lower than in the control. Significant differences of MDA level were detected in patients with stage III after surgery compared to the control. The level of GSH + GSSG was significantly lower in the patients with I–III stages compared to the control. Conclusion: The most expressed changes demonstrate the significance of MDA as a marker to evaluate oxidative stress in breast cancer patients. The degree of oxidative stress depends on the patient’s age and stage of disease. (1) Malondialdehyde can be used as an oxidative stress marker; (2) A higher stage of the disease and older age correspond to a higher rise of malondialdehyde, suggesting more intensive oxidative stress.

An Au@NH2-MIL-125(Ti)-based multifunctional platform for colorimetric detections of biomolecules and Hg2+

Au@NH₂-MIL-125(Ti) was fabricated and explored as a multifunctional platform for sensitive colorimetric detections of biomolecules and Hg²⁺.

The effect of curcumin on lipid peroxidation and selected antioxidants in irradiated rats

The effect of irradiation on oxidants and antioxidants in selected tissues and a possible protective effect of curcumin on these indices were investigated. A total of 28 rats were divided into 3 groups; group 1 was control; group 2 was the irradiation group, saline was administered intraperiotenally (i.p.) for three days and then, 9 Gy gamma irradiation was applied; group 3 was the irradiation + curcumin group: curcumin was given i.p. for three days at 200 mg/kg body weight and then the same dose of irradiation was applied. A significant increase in malondialdehyde (MDA) was detected in the liver, kidney, and brain tissues of the rats as a result of irradiation (P< 0.01). Glutathione peroxidase (GSH-Px) activity in all the tissues (except for kidneys) decreased (P< 0.01), liver SOD (superoxide dismutase) activity decreased (P< 0.05), and GSH (glutathione) levels in kidney and ovary tissues (P< 0.001) significantly increased. While curcumin administration returned the increased MDA levels in the kidneys and brain in result of irradiation to normal (P< 0.01), it did not return the increased MDA levels in the liver tissue to normal (P< 0.001) despite significantly reducing them. While decreased GSH-Px and SOD activity in the liver in result of irradiation increased with the addition of curcumin (P< 0.05), increased GSH levels in the kidneys and ovaries returned to control levels (P< 0.001). When MDA values were examined, it was found that the addition of curcumin protected the liver, kidneys and brain from the oxidative damage caused by irradiation.

Gymnotic delivery and gene silencing activity of reduction-responsive siRNAs bearing lipophilic disulfide-containing modifications at 2'-position

Modified oligoribonucleotides used as siRNAs bearing biolabile disulfide-containing groups at some 2'-positions were synthesized following a post-synthesis transformation of solid-supported 2'-O-acetylthiomethyl RNA, previously described. Thus, the reduction-responsive and lipophilic benzyldithiomethyl (BnSSM) modification was introduced at different locations into siRNAs targeting the Ewing sarcoma EWS-Fli1 protein. Thermal stability, serum stability and response to glutathione treatment of modified siRNAs were thoroughly investigated. Among 17 modified siRNAs, significant gene silencing activities were demonstrated for the 8 most stable siRNAs in serum (half-life > 1 h) when using a transfection reagent. Of special interest, two naked 2'-O-BnSSM siRNAs transfection exhibited a remarkable gene silencing activity after 24 h incubation. These inhibitions are consistent with an efficient gymnotic delivery demonstrated by the presence of the corresponding fluorescent siRNAs within cells.

Synthesis of unsymmetrical disulfanes bearing 1,2,4-triazine scaffold and their in vitro screening towards anti-breast cancer activity

ABSTRACT

A new series of 1,2,4-triazine unsymmetrical disulfanes were prepared and evaluated as anticancer activity compounds against MCF-7 human breast cancer cells with some of them acting as low micromolar inhibitors. Evaluation of the cytotoxicity using an MTT assay, the inhibition of [3H]-thymidine incorporation into DNA demonstrated that these products exhibit cytotoxic effects on breast cancer cells in vitro. The most effective compounds with 59 and 60 µM compared to chlorambucil with 47 µM were disulfanes bearing methyl and methoxy substituent in an aromatic ring. Furthermore, all new 14 compounds were obtained with 22-74% yield via mild and efficient synthesis of the sulfur-sulfur bond formation from thiols and symmetrical disulfanes using 2,3-dichloro-5,6-dicyanobenzoquinone (DDQ). The molecular structure of the newly obtained compounds was confirmed by X-ray analysis. The conformational preferences of disulfide system were characterized using theoretical calculations at DFT level and statistical distributions of C-S-S-C torsion angle values based on the Cambridge Structural Database (CSD). The DFT calculations and CSD searching show two preferential conformations for C-S-S-C torsion angle close to ± 90° and relatively large freedom of rotation on S-S bond in physiological conditions. The molecular docking studies were performed using the human estrogen receptor alpha (ERα) as molecular target to find possible binding orientation and intermolecular interactions of investigated disulfanes within the active site of ERα. The S…H-S and S…H-C hydrogen bonds between sulfur atoms of bisulfide bridge and S-H and C-H groups of Cys530 and Ala350 as protein residues play crucial role in interaction with estrogen receptor for the most anticancer active disulfane.

GRAPHICAL ABSTRACT

Changes of reduced glutathione and glutathione S-transferase levels in colorectal cancer patients undergoing treatment

PURPOSE:

The available data concerning reduced glutathione (GSH) and glutathione S-transferase (GST) levels in colorectal cancer patients during the treatment process are contradictory and insufficient.

METHODS:

Forty patients with metastatic colorectal cancer receiving FOLFOX4 chemotherapy with or without bevacizumab and 40 healthy volunteers were included in the study. Blood samples were taken before treatment, after 2 months and at the end of treatment in the patient group and once in the healthy volunteer group. The levels of GSH and GST in blood serum were evaluated by enzyme-linked immunosorbent assay (ELISA) according to the manufacturer's instructions.

RESULTS:

The serum level of GSH was significantly lower in colorectal cancer patients before treatment than in healthy volunteers (37.84 ± 19.39 μg/mL and 52.78 ± 19.39 μg/mL, respectively; p<0.001). After treatment, the level of GSH increased significantly, while the level of GST decreased significantly. These changes were observed only in the groups of patients with partial or complete response, having metastases only in the liver, receiving FOLFOX4 chemotherapy with bevacizumab, or undergoing resection or radiofrequency ablation of liver metastases.

CONCLUSIONS:

GSH and GST levels change significantly during the treatment process and these changes depend on the response to treatment, treatment type, and site of metastases. Further analysis of the changes in GSH and GST levels during treatment would allow the assessment of the predictive potential of this molecular marker.

Zincke's Salt-Substituted Tetraphenylethylenes for Fluorometric Turn-On Detection of Glutathione and Fluorescence Imaging of Cancer Cells

In this paper, we report Zincke's salt-substituted tetraphenylethylenes 1a and 1b with Cl^- and PF₆^- as counteranions, respectively. The crystal structure of 1b was determined. Both 1a and 1b are almost nonemissive even in the aggregated states. This is attributed to the photoinduced electron transfer from 2,2-bis(4-methoxyphenyl)-1-phenylvinyl-phenyl unit to 1-(2,4-dinitrophenyl) pyridinium unit within 1a and 1b. The results demonstrate that the emissions of 1a and 1b in aqueous solution can be switched on upon either reaction with GSH or light irradiation. On the basis of the reaction between 1a and GSH, 1a can be utilized for the fluorescence turn-on detection of GSH selectively, and GSH with concentration as low as 36.9 nM can be detected. The transformation of 1b into 2 under light irradiation results in the fluorescence imaging of Hela and U2OS cells and phototoxicity toward Hela and U2OS cells after the protonation of pyridine unit in 2 because of the acidic environment of tumor cells. Aggregates of 1b can be up-taken by Hela and U2OS cells and fluorescence imaging has been successfully recorded with CLSM. Moreover, the protonated form of 2 can function as photosensitizer and 1b shows phototoxicity toward tumor cells such as Hela and U2OS cells.

Tumor Acidic Microenvironment Targeted Drug Delivery Based on pHLIP-Modified Mesoporous Organosilica Nanoparticles

Enhancing the tumor-targeting delivery of chemotherapeutic drugs is important yet challenging for improving therapeutic efficacy and reducing the side effects. Here, we first construct a drug delivery system for targeting tumor acidic microenvironment by modification of pH (low) insertion peptide (pHLIP) on mesoporous organosilica nanoparticles (MONs). The MONs has thioether-bridged framework, uniform diameter (60 nm), good biocompatibility, and high doxorubicin (DOX) loading capacity (334 mg/g). The DOX loaded in the pHLIP modified MONs can be released responsive to glutathione and low pH circumstance, ensuring the chemotherapeutic drug exerts higher cytotoxic effects to cancer cells than normal cells because of high intracellular GSH of tumor cells and low pH of tumor microenvironment. Moreover, the engineered MONs exhibit higher cellular uptake in pH 6.5 medium by MDA-MB-231 and MCF-7 cells than the particles decorated with polyethylene glycol (PEG). Importantly, the pHLIP-mosaic MONs with DOX displays better cytotoxic effects against the breast cancer cells in pH 6.5 medium than pH 7.4 medium. The in vivo experiments demonstrate that the pHLIP modified MONs are accumulated in the orthotopic breast cancer via targeting to acidic tumor microenvironment while no serious pathogenic effects was observed. After loading DOX, the pHLIP-modified MONs display better therapeutic effects than the control groups on the growth of MCF-7 breast cancers, showing promise for enhancing chemotherapy.

MnO2 Nanotube-Based NanoSearchlight for Imaging of Multiple MicroRNAs in Live Cells

Sensitive assay and imaging of multiple low-abundance microRNAs (miRNAs) in living cells remain a grand challenge. Herein, based on polyelectrolyte-induced reduction, a facile approach has been proposed to synthesize novel MnO2 nanotubes. Owing to the remarkably strong fluorescence quenching ability, low cytotoxicity, and excellent colloid stability, the as-prepared MnO2 nanotubes showed great potential for simultaneous detection and imaging of multiple miRNAs in vitro and in situ in living cells for the first time. Besides, MnO2 nanotubes can be reduced to Mn2+ by intracellular acid pH or glutathione, which may serve as an activatable contrast reagent for MRI. Therefore, the MnO2 nanotube-based probes, termed "NanoSearchlight", provide a promising, multimodal imaging tool for precise and accurate diagnosis and prognosis of cancers.

A cerium-based metal–organic framework having inherent oxidase-like activity applicable for colorimetric sensing of biothiols and aerobic oxidation of thiols

A cerium-based MOF exhibits oxidase-like activity for colorimetric sensing of biothiols and aerobic oxidation of thiols.

Imbalanced adaptive responses associated with microsatellite instability in cholangiocarcinoma

The adaptive response of the genome protection mechanism occurs in cells when exposed to genotoxic stress due to the overproduction of free radicals via inflammation and infection. In such circumstances, cells attempt to maintain health via several genome protection mechanisms. However, evidence is increasing that this adaptive response may have deleterious effect; a reduction of antioxidant enzymes and/or imbalance in the DNA repair system generates microsatellite instability (MSI), which has procarcinogenic implications. Therefore, the present study hypothesized that MSI caused by imbalanced responses of antioxidant enzymes and/or DNA repair enzymes as a result of oxidative/nitrative stress arising from the inflammatory response is involved in liver fluke-associated cholangiocarcinogenesis. The present study investigated this hypothesis by identifying the expression patterns of antioxidant enzymes, including superoxide dismutase 2 (SOD2) and catalase (CAT), and DNA repair enzymes, including alkyladenine DNA glycosylase (AAG), apurinic endonuclease (APE) and DNA polymerase β (DNA pol β). In addition, the activities of the antioxidant enzymes, SOD2 and CAT, were examined in human cholangiocarcinoma (CCA) tissues using immunohistochemical staining. MSI was also analyzed in human CCA tissues. The resulting data demonstrated that the expression levels of the SOD2 and CAT enzymes decreased. The activities of SOD2 and CAT decreased significantly in the CCA tissues, compared with the hepatic tissue of cadaveric donors. In the DNA repairing enzymes, it was found that the expression levels of AAG and DNA pol β enzymes increased, whereas the expression of APE decreased. In addition, it was found that MSI-high was present in 69% of patients, whereas MSI-low was present in 31% of patients, with no patients classified as having microsatellite stability. In the patients, a MSI-high was correlated with poor prognosis, indicated by a shorter survival rate. These results indicated that the reduction of antioxidant enzymes and adaptive imbalance of base excision repair enzymes in human CCA caused MSI, and may be associated with the progression of cancer.

Inhibition of diethylnitrosamine-induced liver cancer in rats by Rhizoma paridis saponin

Rhizoma Paridis saponin (RPS) had been regarded as the main active components responsible for the anti-tumor effects of the herb Paris polyphylla var. yunnanensis (Franch.) Hand.-Mazz. In the present research, we set up a rat model of diethylnitrosamine (DEN) induced hepatoma to evaluate antitumor effect of RPS. After 20 weeks treatment, rats were sacrificed to perform histopathological examinations, liver function tests, oxidative stress assays and so forth. As a result, DEN-induced hepatoma formation. RPS alleviated levels of liver injury through inhibiting liver tissues of malondialdehyde (MDA) and nitric oxide (NO) formation, increasing superoxide dismutases (SOD) production, and up-regulating expression of GST-α/μ/π in DEN-induced rats. All in all, RPS would be a potent agent inhibiting chemically induced liver cancer in the prospective application.

A highly selective ratiometric fluorescent probe for biothiol and imaging in live cells

A new N-butyl-4-amino-1,8-naphthalimide-based colorimetric and ratiometric fluorescent probe for the detection of biothiols (cysteine, homocysteine, and glutathione) was designed and synthesized.

Selective Fluorescence Detection of Cysteine over Homocysteine and Glutathione Based on a Cysteine-Triggered Dual Michael Addition/Retro-aza-aldol Cascade Reaction

In this work, a cysteine (Cys)-triggered dual Michael addition/retro-aza-aldol cascade reaction has been exploited and utilized to construct a fluorescent probe for Cys for the first time. The resulting fluorescent probe 8-alkynylBodipy 1 contains an activated alkynyl unit as Michael receptor and a Bodipy dye as fluorescence reporter and can highly selectively detect Cys over homocysteine (Hcy)/glutathione (GSH) as well as other amino acids with a significant fluorescence off-on response (∼4500-fold) and an ultralow detection limit (0.38 nM). The high selectivity of 1 for Cys could be attributed to a kinetically favored five-membered cyclic intermediate produced by the dual Michael addition of Cys with the activated alkynyl unit of 1. The big fluorescence off-on response is due to the subsequent retro-aza-aldol reaction of the five-membered cyclic intermediate that results in the release of a highly fluorescent 8-methylBodipy dye 2. The probe has been successfully used to detect and image Cys in serum and cells, respectively.

The development of the LC-MS/MS method based on S-9 biotransformation for detection of metabolites of selected β-adrenolytics in surface water

Pharmaceuticals consumption in Poland is high. One of the most frequently prescribed is cardiovascular drugs. Due to their relatively high hydrophilic properties, they are not completely eliminated during wastewater treatment processes. In contrast to parent compounds, the presence of cardiovascular metabolites is rarely investigated in surface waters. The goal of this paper was to develop the methodology for detection of metabolites of selected beta-blockers: metoprolol, bisoprolol and propranolol. These metabolites were obtained by the incubation of parent compounds with S9 rat's liver fraction and used for the development and optimization of the low resolution LC-MS/MS method. Accurate mass spectrometry measurements were applied for validation of this method. The incubation of the parent compound with S9 fraction resulted only in propranolol's metabolites generation. However, on the basis of hydroxypropranolol, theoretically transitions for mono- and dihydroxy-metoprolol and bisoprolol derivatives were generated for MRM mode and applied for surface water analysis. The analysis revealed the presence of some of the target metabolites in the Vistula river. This work is the first one proposing the application of biotrasformation in the methodology of low resolution LC-MS-MS analysis of metabolites of cardiovascular drugs in surface water.

Protective effects of erdosteine against nephrotoxicity caused by gamma radiation in male albino rats

The aim of this study was focused on investigating the possible protective effect of erdosteine against gamma radiation-induced renal lesions in male albino rats. Twenty-eight albino rats were divided into four equal groups as follows: control group, irradiated group (animals subjected to whole-body gamma irradiation at a dose of 5 Gy), treated group (each rat received 100 mg/kg body weight once daily, orally by gastric tube, erdosteine for 1 week), and treated irradiated group (each rat received 100 mg/kg body weight once daily, orally by gastric tube, erdosteine for 1 week, then exposed to whole-body gamma irradiation at a dose of 5 Gy). The results revealed that the administration of erdosteine to rats before irradiation significantly ameliorated the changes occurred in kidney function (creatinine and urea) compared with irradiated group. Also the changes in serum tumor necrosis factor α, interleukin 1β, and interleukin 6 activities were markedly improved compared with the corresponding values of irradiated group. Kidney catalase and glutathione peroxidase (GPx) activities and reduced glutathione concentration showed approximately normal level when compared with the irradiated group. The histopathological results showed distinctive pattern of renal lesions in irradiated group, while in treated irradiated group the renal tissues showed relatively well-preserved architecture. Erdosteine acts in the kidney as a potent scavenger of free radicals to prevent or ameliorate the toxic effects of gamma irradiation as shown in the biochemical and histopathological changes and might provide substantial protection against radiation-induced inflammatory damage.

Gastroprotective effect of kefir on ulcer induced in irradiated rats

The current study was designed to investigate the protective effect of kefir milk on ethanol-induced gastric ulcers in γ-irradiated rats. The results of the present study revealed that treatment with γ-irradiation and/or ethanol showed a significant increase in ulcers number, total acidity, peptic, H(+)K(+)ATPase, MMP-2 and MMP-9 activities and MDA level, which were accompanied by a significant decrease in the mucus content, the stomach GSH level, the GSH-Px activity and DNA damage. Pre-treatment with kefir milk exert significant improvement in all the tested parameters. Kefir milk exerts comparable effect to that of the antiulcer drug ranitidine. In conclusion, the present study revealed that oral administration of kefir milk prevents ethanol-induced gastric ulcer in γ-irradiated rats that could attribute to its antioxidant, anti-apoptotic and radio-protective activities.

The photodynamic effect of far-red range phthalocyanines (AlPc and Pc green) supported by electropermeabilization in human gastric adenocarcinoma cells of sensitive and resistant type

INTRODUCTION

Electroporation (EP) is commonly applied for effective drug transport thorough cell membranes based on the application of electromagnetic field. When applied with cytostatics, it is called electrochemotherapy (ECT) - a quite new method of cancer treatment. A high-voltage pulse causes the formation of temporary pores in the cell membrane which create an additional way for the intracellular drug transport. In the current work, EP was effectively merged with the already known photodynamic therapy (PDT) to selective photosensitizers' delivery to diseased tissue. The application of electroporation can reduce the dose of applied drug.

RESEARCH OBJECTIVE

The aim of research was to evaluate the effectiveness of photodynamic reaction using two near infrared cyanines (AlPc and Pc green) combined with electroporation in two human gastric adenocarcinoma cell lines.

MATERIALS AND METHODS

Two human cell lines - EPG85-257P (parental) and EPG85-257RDB (resistant to daunorubicin) - of gastric cancer were used. The effect of two photosensitizers (aluminum 1,8,15,22-tetrakis(-phenylthio)-29H,31H-phthalocyanine chloride and Phthalocyanine green) was investigated. The efficiency of EP parameters was assessed by propidium iodide uptake. The viability assay was applied to analyse EP, PDT and EP-PDT effect. Cyanine localization was determined by confocal microscopy. Immunocytochemical evaluation of manganese superoxide dismutase and glutathione S-transferase-pi was determined after applied therapies.

RESULTS

PDT in combination with EP affected the viability of EPG85-257P and EPG85-257RDB cells negatively while both cyanine were used. The most evident changes were observed in the following concentrations: 15, 10 and 5μM. The optimal field strength for enhanced EP-PDT was 800 and 1200V/cm. AlPc distributed selectively in the lysosomes of parental cell line.

CONCLUSIONS

PDT, enhanced by EP, caused decreased viability when compared to the application of PDT alone. Both phthalocyanines found to be more effective after electroporation. Due to the low concentration of light-sensitive compounds and safety of electroporation itself, a treatment plan can be an alternative therapeutic modality against gastric adenocarcinomas.

Matrix metalloproteinases and gastrointestinal cancers: Impacts of dietary antioxidants

The process of carcinogenesis is tightly regulated by antioxidant enzymes and matrix degrading enzymes, namely, matrix metalloproteinases (MMPs). Degradation of extracellular matrix (ECM) proteins like collagen, proteoglycan, laminin, elastin and fibronectin is considered to be the prerequisite for tumor invasion and metastasis. MMPs can degrade essentially all of the ECM components and, most MMPs also substantially contribute to angiogenesis, differentiation, proliferation and apoptosis. Hence, MMPs are important regulators of tumor growth both at the primary site and in distant metastases; thus the enzymes are considered as important targets for cancer therapy. The implications of MMPs in cancers are no longer mysterious; however, the mechanism of action is yet to be explained. Herein, our major interest is to clarify how MMPs are tied up with gastrointestinal cancers. Gastrointestinal cancer is a variety of cancer types, including the cancers of gastrointestinal tract and organs, i.e., esophagus, stomach, biliary system, pancreas, small intestine, large intestine, rectum and anus. The activity of MMPs is regulated by its endogenous inhibitor tissue inhibitor of metalloproteinase (TIMP) which bind MMPs with a 1:1 stoichiometry. In addition, RECK (reversion including cysteine-rich protein with kazal motifs) is a membrane bound glycoprotein that inhibits MMP-2, -9 and -14. Moreover, α2-macroglobulin mediates the uptake of several MMPs thereby inhibit their activity. Cancerous conditions increase intrinsic reactive oxygen species (ROS) through mitochondrial dysfunction leading to altered protease/anti-protease balance. ROS, an index of oxidative stress is also involved in tumorigenesis by activation of different MAP kinase pathways including MMP induction. Oxidative stress is involved in cancer by changing the activity and expression of regulatory proteins especially MMPs. Epidemiological studies have shown that high intake of fruits that rich in antioxidants is associated with a lower cancer incidence. Evidence indicates that some antioxidants inhibit the growth of malignant cells by inducing apoptosis and inhibiting the activity of MMPs. This review is discussed in six subchapters, as follows.

Determination of aerosol oxidative activity using silver nanoparticle aggregation on paper-based analytical devices

Airborne particulate matter (PM) pollution significantly impacts human health, but the cellular mechanisms of PM-induced toxicity remain poorly understood. A leading hypothesis on the effects of inhaled PM involves the generation of cellular oxidative stress. To investigate PM-induced oxidative stress, analytical methods have been developed to study the chemical oxidation of dithiothreitol (DTT) in the presence of PM. Although DTT readily reacts with several forms of reactive oxygen species, this molecule is not endogenously produced in biological systems. Glutathione (GSH), on the other hand, is an endogenous antioxidant that is produced throughout the body and is directly involved in combating oxidative stress in the lungs and other tissues. We report here a new method for measuring aerosol oxidative activity that uses silver nanoparticle (AgNP) aggregation coupled to glutathione (GSH) oxidation in a paper-based analytical device. In this assay, the residual reduced GSH from the oxidation of reduced GSH to its disulfide induces the aggregation of AgNPs on a paper-based analytical device, which produces a reddish-brown product. Two methods for aerosol oxidative reactivity are presented: one based on change in color intensity using a traditional paper-based techniques and one based on the length of the color product formed using a distance-based device. These methods were validated against traditional spectroscopic assays for DTT and GSH that employ Elman's reagent. No significant difference was found between the levels measured by all three GSH methods (our two paper-based devices and the traditional method) at the 95% confidence level. PM reactivity towards GSH was less than towards DTT most likely due to the difference in the oxidation potential between the two molecules.

A dual emission fluorescent probe enables simultaneous detection of glutathione and cysteine/homocysteine

Many studies have shown that glutathione (GSH) and cysteine (Cys) / homocysteine (Hcy) levels are interrelated in biological systems. To unravel the complicated biomedical mechanisms by which GSH and Cys/Hcy are involved in various disease states, probes that display distinct signals in response to GSH and Cys/Hcy are highly desirable. In this work, we report a rhodol thioester (1) that responds to GSH and Cys/Hcy with distinct fluorescence emissions in neutral media. Probe 1 reacts with Cys/Hcy to form the corresponding deconjugated spirolactam via a tandem native chemical ligation (NCL) reaction. This intramolecular spirocyclization leads to the "quinone - phenol" transduction of rhodol dyes, and an excited-state intramolecular proton transfer (ESIPT) process between the phenolic hydroxyl proton and the aromatic nitrogen in the benzothiazole unit occurs upon photoexcitation, thus affording 2-(2'-hydroxyphenyl) benzothiazole (HBT) emission (454 nm). In the case of the tripeptide GSH, only transthioesterification takes place removing the intramolecular photo-induced electron transfer (PET) process caused by the electron deficient 4-nitrobenzene moiety giving rise to a large fluorescence enhancement at the rhodol emission band (587 nm). The simultaneous detection of GSH and Cys/Hcy is attributed to the significantly different rates of intramolecular S,N-acyl shift of their corresponding thioester adducts derived from 1. The utility of probe 1 has been demonstrated in various biological systems including serum and cells.

Oxidative stress-related biomarkers in essential hypertension and ischemia-reperfusion myocardial damage

Cardiovascular diseases are a leading cause of mortality and morbidity worldwide, with hypertension being a major risk factor. Numerous studies support the contribution of reactive oxygen and nitrogen species in the pathogenesis of hypertension, as well as other pathologies associated with ischemia/reperfusion. However, the validation of oxidative stress-related biomarkers in these settings is still lacking and novel association of these biomarkers and other biomarkers such as endothelial progenitor cells, endothelial microparticles, and ischemia modified albumin, is just emerging. Oxidative stress has been suggested as a pathogenic factor and therapeutic target in early stages of essential hypertension. Systolic and diastolic blood pressure correlated positively with plasma F2-isoprostane levels and negatively with total antioxidant capacity of plasma in hypertensive and normotensive patients. Cardiac surgery with extracorporeal circulation causes an ischemia/reperfusion event associated with increased lipid peroxidation and protein carbonylation, two biomarkers associated with oxidative damage of cardiac tissue. An enhancement of the antioxidant defense system should contribute to ameliorating functional and structural abnormalities derived from this metabolic impairment. However, data have to be validated with the analysis of the appropriate oxidative stress and/or nitrosative stress biomarkers.

Status of antioxidant enzyme: glutathione peroxidase and total polyphenol level in plasma of Tunisian patients suffering from colorectal and gastric cancer: interaction with clinical outcome

In our case-control study, we measure the antioxidant status by dosing enzymes involved in oxidant stress in plasma of patients with colorectal and gastric cancer, and in the second step, we investigate the impact of chemotherapy before and after surgery on plasma antioxidant status and polyphenols in patients. Blood serum was collected from patients with stomach and colorectal cancer before conventional treatment, and glutathione peroxidase (GSHPX) enzyme activities and total polyphenols were determined by spectrophotometric methods. In our study, we found a significant decrease in glutathione peroxidase activity in plasma of patients compared with controls (P = 0.02), although we did not find a significant association between total polyphenols and 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) or ABTS in plasma of colorectal and stomach cancer compared with control; furthermore, we observed no significant difference in the average plasma polyphenols in patients treated with chemotherapy before and after surgery. We have shown the decrease in GSHPX activity in plasma of cases with colorectal and gastric cancer, and this decrease reflects that the oxidative stress is associated with tumor tract and related to oxidative metabolism; however, no association was found between total polyphenols and ABTS in our study.

Nitric Oxide is a Potential Diagnostic Marker for Hepatocellular Carcinoma

Hepatocellular carcinoma (HCC) is the fifth most common cancer in men and the seventh most common in women. This cancer varies widely in incidence throughout the world, with rising incidence in Egypt. HCC is considered the second most frequent cause of cancer incidence and mortality among men in Egypt. This study aimed to estimate the serum levels of nitric oxide (NO) and glutathione reductase in order to evaluate their role as oxidative status markers in HCC development and progression. For this purpose, serum levels of these parameters were assessed in 50 HCC patients, and 30 cirrhotic patients in addition to 15 healthy subjects as a control group. In the present study, glutathione reductase activity showed a significant increase in HCC as compared to the control group (P= 0.019). On the other hand, no significant difference was observed between the cirrhotic and HCC patients (P= 0.492). Serum NO was significantly higher in patients with HCC than in cirrhotic patients (P= 0.001) or the control group (P= 0.001), with a sensitivity of (74%) and specificity of (88.89%) at a cut-off level of 614.1 μmol/l. While AFP, alpha-fetoprotein, at a cutoff level of 200 ng/ml had a sensitivity of (52%), the specificity was (100%). Indeed, nitric oxide was high in 62.5% of AFP-negative HCC patients. In conclusion, glutathione reductase has no role in HCC diagnosis. However, nitric oxide is a potential diagnostic marker for HCC. The simultaneous determination of serum nitric oxide and AFP gave significant improvement in the detection of HCC patients compared to that of AFP alone.

A non-surgical method for induction of lung cancer in Wistar rats using a combination of NNK and high dietary fats

Lung cancer is one of the most common malignant neoplasms all over the world. Smoking and a number of constituents of tobacco are responsible for development of lung tumours; however, the deleterious effects of tobacco-derived carcinogen, nitrosamine 4-(methylnitrosoamino)-1-(3-pyridyl)-1-butanone (nicotine-derived nitrosamine ketone (NNK)) remain unmatched. We report the development of a novel rodent model by administering multiple doses of NNK to male Wistar rats and feeding them with high-fat and low-protein diet. Tumour cells in lungs were observed in approximately 98 % rats after 8 months of NNK treatment, as evident by histopathological analysis. This rodent model showed slow progression of lung tumours which has helped us to assess early indicators of oxidative damage in lungs by studying the levels of lipid peroxidation and antioxidant parameters. LPO was elevated by 46.94 %, SOD, CAT, GSH and GR activity was decreased by 48.67 %, 22.04 %, 21.46 % and 20.85 %, respectively in serum of NNK treated rats when compared with control. These findings suggest that increased oxidative stress can represent a risk factor for the development of chronic disease in early future. This new animal model is an attempt to greatly facilitate studies of the pathophysiology, biochemistry and therapy of lung cancer.