Tumors In Rats Research Articles

Carcinogenicity Assessment of Inotersen in Tg.rasH2 Mice and Sprague-Dawley Rats: Implications for 2'-MOE Antisense Oligonucleotides

Inotersen, a 2’-O-(2-methoxyethyl) modified antisense oligonucleotide (2’-MOE ASO), is approved for the treatment of hereditary transthyretin-mediated amyloidosis (hATTR). It underwent a comprehensive nonclinical safety evaluation, including safety pharmacology, repeat-dose toxicity, genotoxicity, reproductive and development toxicity, and carcinogenicity studies. Tumorigenic potential was assessed through dedicated carcinogenicity studies in transgenic rasH2 (Tg.rasH2) mice and Sprague Dawley (SD) rats. In the 26-week Tg.rasH2 mouse study, inotersen and a mouse-active surrogate (ISIS 401724) were administered as weekly subcutaneous (SC) doses up to 80 mg/kg and 30 mg/kg, respectively. Proinflammatory effects and ASO accumulation in the liver and kidney, both well-documented class effects, were observed; however, no treatment-related neoplasms were noted. Similarly, the mouse surrogate did not induce any treatment-related neoplasms. In the 2-year SD rat carcinogenicity study, inotersen was administered as weekly SC doses up to 6 mg/kg. The primary dose-limiting effect at doses ≥2 mg/kg/week was an increased incidence of chronic progressive nephropathy (CPN), which contributed to decreased survival at the 6 mg/kg/week dose level. Notably, no renal neoplasia was associated with the increased CPN. Increasing mononuclear cell infiltrates at the injection site were linked to an increased incidence of subcutaneous fibrosarcoma at doses ≥2 mg/kg/week. This inflammation-associated injection site tumor in rats administered inotersen has limited relevance for humans. Additionally, the long-term assessment of ASO effects in rats is somewhat limited due to the ASO exacerbation of CPN and its impact on survival. There was no evidence of genotoxicity in vitro or in vivo at limit doses. Collectively, these data support a conclusion that a single carcinogenicity assessment in the Tg.rasH2 mouse, along with data from chronic toxicology studies in the rodent and nonrodent, is sufficient to assess carcinogenic potential for this drug class.

Melanocortin-4 receptor antagonist TCMCB07 alleviates chemotherapy-induced anorexia and weight loss in rats.

Cancer patients undergoing chemotherapy often experience anorexia and weight loss that substantially deteriorates overall health, reduces treatment tolerance and quality of life, and worsens oncologic outcomes. There are currently few effective therapeutic options to mitigate these side effects. The central melanocortin system, which plays a pivotal role in regulating appetite and energy homeostasis, presents a logical target for treating anorexia and weight loss. In this preclinical study, we evaluated the efficacy of TCMCB07, a synthetic antagonist of the melanocortin-4 receptor, in mitigating anorexia and weight loss in several rat models of chemotherapy: cisplatin, 5-fluorouracil, cyclophosphamide, vincristine, doxorubicin, and a combination of irinotecan and 5-fluorouracil. Our results indicate that peripheral administration of TCMCB07 improved appetite, stabilized body weight, preserved fat and heart mass, and slightly protected lean mass after multiple cycles of chemotherapy. Furthermore, combining TCMCB07 with a growth differentiation factor 15 antibody enhanced treatment effectiveness. Similar effects from TCMCB07 treatment were observed in a rat tumor model following combination chemotherapy. No notable adverse effects nor increased chemotherapy-related toxicities were observed with TCMCB07 treatment. These findings suggest that peripheral administration of TCMCB07 holds promise as a therapeutic approach for alleviating chemotherapy-induced anorexia and weight loss, potentially benefiting numerous patients undergoing chemotherapy.

Anti-tumor property of Argemone mexicana leaves methanol extracts against 7, 12- Dimethylbenz[a]anthracene (DMBA) induced mammary tumors in experimental rats

Background: Breast cancer is a complex and multistage process. Many natural compounds are available for an effective and efficient alternative method against breast cancer. This study focused on the anti-cancer activity of Argemone mexicana leaf extract on Dimethylbenz[a]anthracene (DMBA)-induced mammary tumors in experimental rats. Materials and Methods: Argemone mexicana Leaves (AML) were collected, extracted by soxhlet apparatus with methanol solvent, and analyzed by Gas Chromatography and Mass-Spectroscopy (GCMS). Healthy Female Sprague-Dawley rats (7-8 weeks and 100 ± 20 g) were divided in five groups and used to induce mammary tumors by DMBA [25 mg/kg/ Subcutaneous (s.c.)]. After developing a palpable nodule (10-12 weeks after DMBA), the rats were treated with AML extract [200 and 400 mg/kg/Body Weight (b.w.)] and Tamoxifen (TAM 10 mg/kg) orally for 12 weeks. Body weight, tumor weight and volume measurements, lipid peroxidation, antioxidant and tumor marker [Carcinoembryonic Antigen (CEA)] levels, and histological investigations were assessed. Results: Following AML treatment, there was a reduction in weight and volume (P< 0.01) of breast tumor, as well as a significant decrease in levels of lipid peroxidation and tumor marker CEA (P < 0.001) and improved Superoxide Dismutase (SOD), Reduced glutathione (GSH), and caspase levels (P < 0.001). In cytological results, AML improved the cellular architecture, and significant restoration in histopathological examinations revealed a tumor with minimal glandular epithelium proliferation, a decrease in mitotic figures, and nuclear alterations. Conclusion: The study suggests that AML extract has a chemoprotective effect against DMBA-induced mammary tumors in experimental animals, specifying its possibility as a therapeutic agent for breast cancer treatment.

Unveiling the Anticarcinogenic Potential of Inula racemosa Hook. f. Root Extract Against DMBA-Induced Mammary Tumour in Sprague Dawley Rats.

The Himalayan plant Inula racemosa has medicinal properties and can be used to prevent or treat cancer. This is because it contains certain chemicals that are known to fight cancer cells with few or no side effects. I. racemosa has been used for this purpose for many years in traditional medicine and has shown promising results. The present study was crafted to explore the suppressive impacts on cellular proliferation of the root extract derived from I. racemosa via in vivo experimentation. I. racemosa (IR) root extract was tested at three different doses (100, 250, and 500 mg/Kg BW) for 18 weeks to assess its anti-neoplastic activity against mammary tumors in female rats. The assessment included various parameters such as hematological and biochemical indices, tumor parameters, oxidative stress analysis, gross and histopathological lesion determination, Masson's trichrome staining, immunohistochemical expression of Ki-67, MMP-9, and VEGF in mammary gland tissues, and molecular docking. The chemopreventive action of IR root extract was demonstrated by the inhibition of tumor parameters (tumor size and tumor volume), minimum changes in the liver (ALT, AST, and ALP) and kidney enzymes (BUN and creatinine), declined lipid peroxidation activity, decline gross, and histological changes in mammary gland tumors, reduced expression of KI-67, MMP-9, and VEGF and maximum binding affinity of isoalantolactone with VEGF through molecular docking. The study suggests that the active constituents (isoalantolactone and alantolactone) of I. racemosa roots have anti-neoplastic activity against mammary tumors, making them a valuable therapeutic regimen for the future.

Promoting effect of sunset yellow on N-methyl N-nitrosourea-induced rat mammary carcinogenesis: Implications of molecular mechanisms

BackgroundNowadays, the use of food additives, such as Sunset Yellow (SY), is growing, which attracted attention to the potential relationship between some diseases and food additives. AimThe study aimed to investigate the role of Sunset Yellow during chemically-induced mammary gland carcinogenesis in Sprague–Dawley rats. Material and methodsThree groups of female rats were intraperitoneally administered with N-methyl-N-nitrosourea (MNU). Group 1 was set on a basal diet. Group 2 was treated with 161.4 mg\\kg\\day Sunset Yellow (SY). Group 3 was given SY at 80.7 mg\\kg\\day. Groups 4–6 were not administered MNU; Group 4 received vehicles only. Groups 5 and 6 were administered SY similarly to groups 2 and 3 respectively. ResultsSunset Yellow at both doses exerted a significant dose-dependent increase in tumor incidences, multiplicities, volumes, and decreased tumor latency as compared with control. Immunolabeling indexes of the proliferating cell nuclear antigen, estrogen receptor alpha, and progesterone receptor were significantly increased after SY treatment. Oxidative stress markers, serum estrogen, progesterone, and prolactin levels were significantly modified by SY treatment. The mRNA expression of estrogen receptor alpha and epidermal growth factor was up-regulated in SY groups versus control. ConclusionCollectively, SY has significantly promoted MNU-induced mammary tumors in rats with underlying mechanisms correlating SY consumption with estrogen disruption and subsequent antioxidative stress discrepancy.

Risk assessment of small organoarsenic species in food.

The European Commission asked EFSA for a risk assessment on small organoarsenic species in food. For monomethylarsonic acid MMA(V), decreased body weight resulting from diarrhoea in rats was identified as the critical endpoint and a BMDL10 of 18.2 mg MMA(V)/kg body weight (bw) per day (equivalent to 9.7 mg As/kg bw per day) was calculated as a reference point (RP). For dimethylarsinic acid DMA(V), increased incidence in urinary bladder tumours in rats was identified as the critical endpoint. A BMDL10 of 1.1 mg DMA(V)/kg bw per day (equivalent to 0.6 mg As/kg bw per day) was calculated as an RP. For other small organoarsenic species, the toxicological data are insufficient to identify critical effects and RPs, and they could not be included in the risk assessment. For both MMA(V) and DMA(V), the toxicological database is incomplete and a margin of exposure (MOE) approach was applied for risk characterisation. The highest chronic dietary exposure to DMA(V) was estimated in 'Toddlers', with rice and fish meat as the main contributors across population groups. For MMA(V), the highest chronic dietary exposures were estimated for high consumers of fish meat and processed/preserved fish in 'Infants' and 'Elderly' age class, respectively. For MMA(V), an MOE of ≥ 500 was identified not to raise a health concern. For MMA(V), all MOEs were well above 500 for average and high consumers and thus do not raise a health concern. For DMA(V), an MOE of 10,000 was identified as of low health concern as it is genotoxic and carcinogenic, although the mechanisms of genotoxicity and its role in carcinogenicity of DMA(V) are not fully elucidated. For DMA(V), MOEs were below 10,000 in many cases across dietary surveys and age groups, in particular for some 95th percentile exposures. The Panel considers that this would raise a health concern.

Temporal and regional expression changes and co-staining patterns of metabolic and stemness-related markers during glioblastoma progression.

Glioblastomas (GBMs) are characterized by high heterogeneity, involving diverse cell types, including those with stem-like features contributing to GBM's malignancy. Moreover, metabolic alterations promote growth and therapeutic resistance of GBM. Depending on the metabolic state, antimetabolic treatments could be an effective strategy. Against this background, we investigated temporal and regional expression changes and co-staining patterns of selected metabolic markers [pyruvate kinase muscle isozyme 1/2 (PKM1/2), glucose transporter 1 (GLUT1), monocarboxylate transporter 1/4 (MCT1/4)] in a rodent model and patient-derived samples of GBM. To understand the cellular sources of marker expression, we also examined the connection of metabolic markers to markers related to stemness [Nestin, Krüppel-like factor 4 (KLF4)] in a regional and temporal context. Rat tumour biopsies revealed a temporally increasing expression of GLUT1, higher expression of MCT1/4, Nestin and KLF4, and lower expression of PKM1 compared to the contralateral hemisphere. Patient-derived tumours showed a higher expression of PKM2 and Nestin in the tumour centre vs. edge. Whereas rare co-staining of GLUT1/Nestin was found in tumour biopsies, PKM1/2 and MCT1/4 showed a more distinct co-staining with Nestin in rats and humans. KLF4 was mainly co-stained with GLUT1, MCT1 and PKM1/2 in rat and human tumours. All metabolic markers yielded individual co-staining patterns among themselves. Co-staining mainly occurred later in tumour progression and was more pronounced in tumour centres. Also, positive correlations were found amongst markers that showed co-staining. Our results highlight a link between metabolic alterations and stemness in GBM progression, with complex distinctions depending on studied markers, time points and regions.

Sophoridine exerts anti-arthritic effects on fibroblast-like synoviocytes and collagen-induced arthritis in rats.

The discovery of alternative medicines with fewer adverse effects is urgently needed for rheumatoid arthritis (RA). Sophoridine (SR), the naturally occurring quinolizidine alkaloid isolated from the leguminous sophora species, has been demonstrated to possess a wide range of pharmacological activities. However, the effect of SR on RA remains unknown. In this study, the collagen-induced arthritis (CIA) rat model and tumor necrosis factor alpha (TNFα)-induced fibroblast-like synoviocytes (FLSs) were utilized to investigate the inhibitory effect of SR on RA. The anti-arthritic effect of SR was evaluated using the CIA rat model in vivo and TNFα-stimulated FLSs in vitro. Mechanistically, potential therapeutic targets and pathways of SR in RA were analyzed through drug target databases and disease databases, and validation was carried out through immunofluorescence, immunohistochemistry, and Western blot. The in vivo results revealed that SR treatment effectively ameliorated synovial inflammation and bone erosion in rats with CIA. The in vitro studies showed that SR could significantly suppress the proliferation and migration in TNFα-induced arthritic FLSs. Mechanistically, SR treatment efficiently inhibited the activation of MAPKs (JNK and p38) and NF-κB pathways in TNFα-induced arthritic FLSs. These findings were further substantiated by Immunohistochemistry results in the CIA rat. SR exerts an anti-arthritic effect in CIA rats through inhibition of the pathogenic characteristic of arthritic FLSs via suppressing NF-κB and MAPKs (JNK and p38) signaling pathways. SR may have a great potential for development as a novel therapeutic agent for RA treatment.

Human cancer genomes harbor the mutational signature of tobacco-specific nitrosamines NNN and NNK.

Tobacco usage is linked to multiple cancer types and accounts for a quarter of all cancer-related deaths. Tobacco smoke contains various carcinogenic compounds, including polycyclic aromatic hydrocarbons (PAH), though the mutagenic potential of many tobacco-related chemicals remains largely unexplored. In particular, the highly carcinogenic tobacco-specific nitrosamines NNN and NNK form pre-mutagenic pyridyloxobutyl (POB) DNA adducts. In the study presented here, we identified genome-scale POB-induced mutational signatures in cell lines and rat tumors, while also investigating their role in human cancer. These signatures are characterized by T>N and C>T mutations forming from specific POB adducts damaging dT and dC residues. Analysis of 2,780 cancer genomes uncovered POB signatures in ∼180 tumors; from cancer types distinct from the ones linked to smoking-related signatures SBS4 and SBS92. This suggests that, unlike PAH compounds, the POB pathway may contribute uniquely to the mutational landscapes of certain hematological malignancies and cancers of the kidney, breast, prostate and pancreas.

CarcSeq detection of lorcaserin-induced clonal expansion of Pik3ca H1047R mutants in rat mammary tissue.

Lorcaserin is a 5-hydroxytryptamine 2C (serotonin) receptor agonist and a nongenotoxic rat carcinogen, which induced mammary tumors in male and female rats in a 2-yr bioassay. Female Sprague Dawley rats were treated by gavage daily with 0, 30, or 100 mg/kg lorcaserin, replicating bioassay dosing but for shorter duration, 12 or 24 wk. To characterize exposure and eliminate possible confounding by a potentially genotoxic degradation product, lorcaserin and N-nitroso-lorcaserin were quantified in dosing solutions, terminal plasma, mammary, and liver samples using ultra-high-performance liquid chromatography-electrospray tandem mass spectrometry. N-nitroso-lorcaserin was not detected, supporting lorcaserin classification as nongenotoxic carcinogen. Mammary DNA samples (n = 6/dose/timepoint) were used to synthesize PCR products from gene segments encompassing hotspot cancer driver mutations, namely regions of Apc, Braf, Egfr, Hras, Kras, Nfe2l2, Pik3ca, Setbp1, Stk11, and Tp53. Mutant fractions (MFs) in the amplicons were quantified by CarcSeq, an error-corrected next-generation sequencing approach. Considering all recovered mutants, no significant differences between lorcaserin dose groups were observed. However, significant dose-responsive increases in Pik3ca H1047R mutation were observed at both timepoints (ANOVA, P < 0.05), with greater numbers of mutants and mutants with greater MFs observed at 24 wk as compared with 12 wk. These observations suggest lorcaserin promotes outgrowth of spontaneously occurring Pik3ca H1047R mutant clones leading to mammary carcinogenesis. Importantly, this work reports approaches to analyze clonal expansion and demonstrates CarcSeq detection of the carcinogenic impact (selective Pik3ca H0147R mutant expansion) of a nongenotoxic carcinogen using a treatment duration as short as 3 months.

Follow-Up Research on NTP’s Clear Evidence on RF Causing Malignant Tumors in Rats [Health Matters

Follow-Up Research on NTP’s Clear Evidence on RF Causing Malignant Tumors in Rats [Health Matters

Mode of action analysis for fluxapyroxad-induced rat liver tumour formation: evidence for activation of the constitutive androstane receptor and assessment of human relevance

The fungicide fluxapyroxad (BAS 700 F) has been shown to significantly increase the incidence of liver tumours in male Wistar rats at dietary levels of 1500 and 3000 ppm and in female rats at a dietary level of 3000 ppm via a non-genotoxic mechanism. In order to elucidate the mode of action (MOA) for fluxapyroxad-induced rat liver tumour formation a series of in vivo and in vitro investigative studies were undertaken. The treatment of male and female Wistar rats with diets containing 0 (control), 50, 250, 1500 and 3000 ppm fluxapyroxad for 1, 3, 7 and 14 days resulted in a dose-dependent increases in relative weight at 1500 and 3000 ppm from day 3 onwards in both sexes, with an increase in relative liver weight being also observed in male rats given 250 ppm fluxapyroxad for 14 days. Examination of liver sections revealed a centrilobular hepatocyte hypertrophy in some fluxapyroxad treated male and female rats. Hepatocyte replicative DNA synthesis (RDS) was significantly increased in male rats given 1500 and 3000 ppm fluxapyroxad for 3 and 7 days and in female rats given 50–3000 ppm fluxapyroxad for 7 days and 250–3000 ppm fluxapyroxad for 3 and 14 days; the maximal increases in RDS in both sexes being observed after 7 days treatment. The treatment of male and female Wistar rats with 250–3000 ppm fluxapyroxad for 14 days resulted in significant increases in hepatic microsomal total cytochrome P450 (CYP) content and CYP2B subfamily-dependent enzyme activities. Male Wistar rat hepatocytes were treated with control medium and medium containing 1–100 μM fluxapyroxad or 500 μM sodium phenobarbital (NaPB) for 4 days. Treatment with fluxapyroxad and NaPB increased CYP2B and CYP3A enzyme activities and mRNA levels but had little effect on markers of CYP1A and CYP4A subfamily enzymes and of the peroxisomal fatty acid β-oxidation cycle. Hepatocyte RDS was significantly increased by treatment with fluxapyroxad, NaPB and 25 ng/ml epidermal growth factor (EGF). The treatment of hepatocytes from two male human donors with 1–100 μM fluxapyroxad or 500 μM NaPB for 4 days resulted in some increases in CYP2B and CYP3A enzyme activities and CYP mRNA levels but had no effect on hepatocyte RDS, whereas treatment with EGF resulted in significant increase in RDS in both human hepatocyte preparations. Hepatocytes from male Sprague-Dawley wild type (WT) and constitutive androstane receptor (CAR) knockout (CAR KO) rats were treated with control medium and medium containing 1–16 μM fluxapyroxad or 500 μM NaPB for 4 days. While both fluxapyroxad and NaPB increased CYP2B enzyme activities and mRNA levels in WT hepatocytes, only minor effects were observed in CAR KO rat hepatocytes. Treatment with both fluxapyroxad and NaPB only increased RDS in WT and not in CAR KO rat hepatocytes, whereas treatment with EGF increased RDS in both WT and CAR KO rat hepatocytes. In conclusion, a series of in vivo and in vitro investigative studies have demonstrated that fluxapyroxad is a CAR activator in rat liver, with similar properties to the prototypical CAR activator phenobarbital. A robust MOA for fluxapyroxad-induced rat liver tumour formation has been established. Based on the lack of effect of fluxapyroxad on RDS in human hepatocytes, it is considered that the MOA for fluxapyroxad-induced liver tumour formation is qualitatively not plausible for humans.

Time Efficient Ultrasound Localization Microscopy Based on A Novel Radial Basis Function 2D Interpolation.

Ultrasound localization microscopy (ULM) allows for the generation of super-resolved (SR) images of the vasculature by precisely localizing intravenously injected microbubbles. Although SR images may be useful for diagnosing and treating patients, their use in the clinical context is limited by the need for prolonged acquisition times and high frame rates. The primary goal of our study is to relax the requirement of high frame rates to obtain SR images. To this end, we propose a new time-efficient ULM (TEULM) pipeline built on a cutting-edge interpolation method. More specifically, we suggest employing Radial Basis Functions (RBFs) as interpolators to estimate the missing values in the 2-dimensional (2D) spatio-temporal structures. To evaluate this strategy, we first mimic the data acquisition at a reduced frame rate by applying a down-sampling (DS = 2, 4, 8, and 10) factor to high frame rate ULM data. Then, we up-sample the data to the original frame rate using the suggested interpolation to reconstruct the missing frames. Finally, using both the original high frame rate data and the interpolated one, we reconstruct SR images using the ULM framework steps. We evaluate the proposed TEULM using four in vivo datasets, a Rat brain (dataset A), a Rat kidney (dataset B), a Rat tumor (dataset C) and a Rat brain bolus (dataset D), interpolating at the in-phase and quadrature (IQ) level. Results demonstrate the effectiveness of TEULM in recovering vascular structures, even at a DS rate of 10 (corresponding to a frame rate of sub-100Hz). In conclusion, the proposed technique is successful in reconstructing accurate SR images while requiring frame rates of one order of magnitude lower than standard ULM.

H-ras-targeted genetic therapy remarkably surpassed docetaxel treatment in inhibiting chemically induced hepatic tumors in rats

AimsHepatocellular carcinoma (HCC) is still a leading cause of cancer-related death worldwide. But its chemotherapeutic options are far from expectation. We here compared H-ras targeted genetic therapy to a commercial docetaxel formulation (DXT) in inhibiting HCC in rats. Main methodsAfter the physicochemical characterization of phosphorothioate-antisense oligomer (PS-ASO) against H-ras mutated gene, the PS-ASO-mediated in vitro hemolysis, in vivo hepatic uptake, its pharmacokinetic profile, tissue distribution in some highly perfused organs, its effect in normal rats, antineoplastic efficacy in carcinogen-induced HCC in rats were evaluated and compared against DXT treatment. Mutated H-ras expression by in situ hybridization, hep-par-I, CK-7, CD-15, p53 expression patterns by immunohistochemical methods, scanning electron microscopic evaluation of hepatic architecture, various hepatic marker enzyme levels and caspase-3/9 apoptotic enzyme activities were also carried out in the experimental rats. Key findingsPS-ASO showed low in vitro hemolysis (<3 %), and had a sustained PS-ASO blood residence time in vivo compared to DTX, with a time-dependent hepatic uptake. It showed no toxic manifestations in normal rats. PS-ASO distribution was although initially less in the lung than liver and kidney, but at 8 h it accumulated more in lung than kidney. Antineoplastic potential of PS-ASO (treated for 6 weeks) excelled in inhibiting chemically induced tumorigenesis compared to DTX in rats, by inhibiting H-ras gene expression, some immonohistochemical modulations, and inducing caspase-3/9–mediated apoptosis. It prevented HCC-mediated lung metastatic tumor in the experimental rats. SignificancePS-ASO genetic therapy showed potential to inhibit HCC far more effectively than DXT in rats.

Abstract 759: Soy protein diet changes metabolic profile in liver of 7,12-dimethylbenz(α)anthracene (DMBA)-induced mammary tumors in obese zucker rats

Abstract Obesity is associated with the risk of certain types of cancers development including breast cancer. Previously, we reported that obesity increased mammary tumor development using obese Zucker rat model. Several studies have shown the health benefit of soy protein consumption. However, the effects of soy protein diet on liver of mammary tumor for oxidative stress and DNA reaction is less known. We used DMBA induced-mammary tumor model to investigate the effects of soy protein diet on pro-oxidative environment and oxidative DNA modification in liver of obese DMBA mammary tumors rats. Female obese zucker rats (n=45) were either fed casein as control (OC; n=20) or soy protein isolate (OS; n=25), received DMBA (65mg/kg BW) at the age 50 days and sacrificed 20 weeks later. We used HPLC-ECD, HPLC-UV and LC-MS techniques for liver metabolic analysis. Comparing liver of OS vs. OC, soy protein 1) decreased the level of Methionine (P&amp;lt;0.02), increased 2) free reduced Homocysteine (P&amp;lt;0.02), 3) S-Adenosylmethionine (SAM, P&amp;lt;0.03), 4) S-Adenosyhomocysteine (SAH, P&amp;lt;0.001) and 5) 5methyl-Cytosine (5mC, P&amp;lt;0.03). Also, soy protein decreased (P&amp;lt;0.003) level of free oxidized Glutathione (GSSG), increased (P&amp;lt;0.02) GSH/GSSG oxidative stress ratio, without any changes a level of free reduced Glutathione (GSH), followed decrease (P&amp;lt;0.04) in liver DNA level of 8-OH-Guanosine (8-OH-G) and level (P&amp;lt;0.02) of 5hmethyl-Cytosine (5hmC). Our results shows soy protein diet capable change liver metabolism: a. Modify a methylation status by increasing levels of SAM (universal methyl group donor) following global liver DNA hypermethylation (5mC), and SAH (methylases inhibitor); b. Alleviate level of oxidative stress in liver by decreasing level of GSSG (not active glutathione), increasing GSH/GSSG ratio (antioxidative capacities), following lower ROS liver DNA damages by decrease levels of 8-OH-G and 5hmC. In conclusion, using obese DMBA-induced mammary tumor Zucker rat model, soy diet making a complex and significantly modification of metabolic conditions in liver affecting both methionine cycle and transsulfuration metabolic pathways. Citation Format: Reza Hakkak, Stepan Melnyk. Soy protein diet changes metabolic profile in liver of 7,12-dimethylbenz(α)anthracene (DMBA)-induced mammary tumors in obese zucker rats [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 759.

Abstract 7299: Preventing CRC progression in FAP rat model using a combinational targeting of TRAIL signaling and inflammation

Abstract Colorectal Cancer (CRC) is among the leading causes of mortality globally, with high incidence rates in developed countries including the US. While FAP patients are prone to develop CRC in their lifetime, recent rising trends among young adults is also a major concern. Hence, preventing CRC would aid in reducing cancer mortality, especially in high-risk FAP patients for which there are no FDA approved preventive agents. Here, we evaluated TRAIL-inducing, orally active small molecule ONC201, alone and in combination with the NSAID naproxen (NAP) for CRC prevention in the PIRC rat model representing FAP cohort. Male PIRC rats were bred inhouse and randomized by age into placebo and intervention groups (N=15). Starting at 6 weeks of age, experimental groups were administered either ONC201 alone by gavage [25mg/kg; 2X/week or 50mg/kg; 1X/week]; NAP in AIN-76A diet [200 ppm; continuously or 1 week ON/OFF]; or a combination of both agents, while placebo group received vehicle only. After 26 weeks of treatment, rats were euthanized and intestines were evaluated for tumor incidence and multiplicity. H&amp;E stained colonic tumor sections were histologically classified as hyperplastic polyps, adenomas (AD), and adenocarcinomas (ADCA). Gross tumor data indicated significant reduction in colonic polyps in both the NAP alone and NAP+ONC201 groups without any overt-toxicites. Histological analyses also demonstrated strong suppression of AD progression to ADCA as well as a significant decrease in the number of ADs and ADCAs (p&amp;lt;0.05) in the treatment groups compared to the placebo. ONC201 regimens modestly reduced AD (19%-27% less, p&amp;lt;0.05) but showed strong inhibition of ADCA (45%-59% less, p&amp;lt;0.0001). A significant reduction of AD and ADCA was seen in NAP continuous (54% &amp; 87% less respectively; p&amp;lt;0.0001) and intermittent (34% &amp; 68% less respectively; p&amp;lt;0.0001) dosing regimens. As anticipated, the NAP continuous treatment had better efficacy than the intermittent dosing regimen. Notably, the combination treatment showed &amp;gt;90% (p&amp;lt;0.0001) inhibition of ADCA and 40%-57% (p&amp;lt;0.0001) inhibition of ADs. Importantly, ONC201+ NAP treatment also resulted in an additional 45% - 70% reduction of ADCA (p&amp;lt;0.0001) when compared to the NAP alone treatment. Thus, our data showed that the combination groups with NAP intermittent dosing demonstrated ~90% inhibition of ADCA, suggesting the synergistic effect of the two agents in preventing CRC progression. Molecular analysis of the rat tumors and additional analyses in in-vitro tumoroid models suggested induction of TRAIL (TRAIL, DR5, FADD), increased apoptosis (Caspases), and a decrease in proliferation markers (PCNA, Cyclin D1) and pro-inflammatory cytokines (IL1b, IL13 etc.). Our data suggests NAP/ONC201 combo has no toxicities, warranting further investigation of CRC interception in high-risk FAP patients (Funding by NCI-PREVENT 75N91019D00020-75N91020F00004). Citation Format: Venkateshwar Madka, Gopal Pathuri, Karthikkumar Venkatachalam, Surya P. Singh, Anil Singh, Nicole Stratton, Stanley Lightfoot, Shizuko Sei, Mark S. Miller, Chinthalapally V. Rao. Preventing CRC progression in FAP rat model using a combinational targeting of TRAIL signaling and inflammation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 7299.

Evaluating the mode of action of perfluorooctanoic acid-induced liver tumors in male Sprague-Dawley rats using a toxicogenomic approach

The mode of action (MOA) underlying perfluorooctanoic acid (PFOA)-induced liver tumors in rats is proposed to involve peroxisome proliferator-activated receptor α (PPARα) agonism. Despite clear PPARα activation evidence in rodent livers, the mechanisms driving cell growth remain elusive. Herein, we used dose-responsive apical endpoints and transcriptomic data to examine the proposed MOA. Male Sprague-Dawley rats were treated with 0, 1, 5, and 15 mg/kg PFOA for 7, 14, and 28 days via oral gavage. We showed PFOA induced hepatomegaly along with hepatocellular hypertrophy in rats. PPARα was activated in a dose-dependent manner. Toxicogenomic analysis revealed six early biomarkers (Cyp4a1, Nr1d1, Acot1, Acot2, Ehhadh, and Vnn1) in response to PPARα activation. A transient rise in hepatocellular DNA synthesis was demonstrated while Ki-67 labeling index showed no change. Transcriptomic analysis indicated no significant enrichment in pathways related to DNA synthesis, apoptosis, or the cell cycle. Key cyclins including Ccnd1, Ccnb1, Ccna2, and Ccne2 were dose-dependently suppressed by PFOA. Oxidative stress and the nuclear factor-κB signaling pathway were unaffected. Overall, evidence for PFOA-induced hepatocellular proliferation was transient within the studied timeframe. Our findings underscore the importance of considering inter-species differences and chemical-specific effects when evaluating the carcinogenic risk of PFOA in humans.

Genetic profiling of rat gliomas and cardiac schwannomas from life-time radiofrequency radiation exposure study using a targeted next-generation sequencing gene panel.

The cancer hazard associated with lifetime exposure to radiofrequency radiation (RFR) was examined in Sprague Dawley (SD) rats at the Ramazzini Institute (RI), Italy. There were increased incidences of gliomas and cardiac schwannomas. The translational relevance of these rare rat tumors for human disease is poorly understood. We examined the genetic alterations in RFR-derived rat tumors through molecular characterization of important cancer genes relevant for human gliomagenesis. A targeted next-generation sequencing (NGS) panel was designed for rats based on the top 23 orthologous human glioma-related genes. Single-nucleotide variants (SNVs) and small insertion and deletions (indels) were characterized in the rat gliomas and cardiac schwannomas. Translational relevance of these genetic alterations in rat tumors to human disease was determined through comparison with the Catalogue of Somatic Mutations in Cancer (COSMIC) database. These data suggest that rat gliomas resulting from life-time exposure to RFR histologically resemble low grade human gliomas but surprisingly no mutations were detected in rat gliomas that had homology to the human IDH1 p.R132 or IDH2 p.R172 suggesting that rat gliomas are primarily wild-type for IDH hotspot mutations implicated in human gliomas. The rat gliomas appear to share some genetic alterations with IDH1 wildtype human gliomas and rat cardiac schwannomas also harbor mutations in some of the queried cancer genes. These data demonstrate that targeted NGS panels based on tumor specific orthologous human cancer driver genes are an important tool to examine the translational relevance of rodent tumors resulting from chronic/life-time rodent bioassays.

Exploration of tumor growth regression of quinoa and chia oil nanocapsules via the control of PIK3CA and MYC expression, anti-inflammation and cell proliferation inhibition, and their hepatorenal safety in rat breast cancer model

BackgroundThe second most common cancer in the world is breast cancer. Chemotherapy is used to treat breast cancer, but instances of multidrug resistance, targets that are not selective, and physicochemical issues raise doubts about its efficacy. So, the exploration of chemopreventive agents from efficient natural sources has been required. The chia and quinoa seeds have health-promoting activities that include cardio-protective, antidiabetic, and anticancer effects. Given the paramount importance of their oils and their potential bioactivities, this work aimed to assess the repressive effect of their oil nanocapsules against mammary tumors in rats. Rat models of chemically induced mammary tumors were gavaged with chia and quinoa nanocapsules for one month. The repressive effect of nanocapsules was studied by quantifying TNF-α, assessing the gene expression of proto-oncogenes (PIK3CA and MYC) using qRT-PCR, and analyzing the cell cycle in mammary tissue.ResultsThe studies clarified that the inhibition of tumors in response to quinoa and chia nanocapsules was associated with a reduction in TNF-α levels, proliferation capability, and motivation for apoptosis. Furthermore, quinoa and chia nanocapsule management repressed the activation of the MYC and PIK3CA genes. As well as nanocapsules modulated the liver enzymes and kidney function alterations induced in mammary tumor animals. Meanwhile, both oils' nanocapsules do not have an impact on the liver and kidneys of healthy rats.ConclusionsThe findings indicate that quinoa and chia nanocapsules are safe and can reduce tumor growth, suggesting a potential natural therapeutic target for breast cancer treatment.

Study on the therapeutic effect and some immune factors by methotrexate modified superparamagnetic nanoparticles in rat mammary tumors.

Objective: this study investigates the efficacy, immunological impact, and preliminary safety of methotrexate (MTX) modified magnetic Fe3O4 nanoparticles in thermochemotherapy for mammary tumors in rats. Methods: transmission electron microscopy images revealed that the MTX-modified magnetic Fe3O4 nanoparticles are nearly spherical, approximately 10 nm in diameter. Chemically co-precipitated PEI-modified magnetic nanoparticles were utilized for thermotherapy, while MTX-modified nanoparticles were employed for thermochemotherapy. These nanoparticles were locally injected into the Walker-256 tumor tissues of Wistar rats. The experimental design included twelve groups, encompassing various protocols of thermotherapy and thermochemotherapy at 47 °C and 42 °C, a group receiving only MTX nanoparticle chemotherapy, and several control groups. The biodistribution of residual magnetic nanoparticles was assessed in vital organs such as the heart, liver, lungs, kidneys, and brain. Results: demonstrated that these magnetic nanoparticles primarily accumulated in the tumor's central region and were unevenly distributed at the margins. The nanoparticles were capable of penetrating tumor cells but were more dispersed around them. Importantly, no residual magnetic nanoparticles were detected in vital organs. Significant tumor reduction and prolonged survival times were observed in the 47 °C thermochemotherapy group, the 47 °C thermotherapy group and the repeated 42 °C thermochemotherapy group. Additionally, significant increases in IL-2 and IFN-γ levels, along with a decrease in IL-4 levels, were detected in the 47 °C thermochemotherapy and 47 °C thermotherapy groups. Conclusion: MTX-modified Fe3O4 magnetic nanoparticles demonstrate potential as an effective medium for thermochemotherapy. They are safe, tolerable, contribute to prolonged survival, and enhance immune functions in tumor-bearing rats without leaving residues in vital organs. These results provide a promising foundation for future cancer treatment research.