Experimental Cancer Models Research Articles

Elevated α/β ratio after hypofractionated radiotherapy correlated with DNA damage repairment in an experimental model of prostate cancer.

Our previous study demonstrated that the linear quadratic model appeared to be not well-suited for high dose per fraction due to an observed increase in α/β ratio as the dose per fraction increased. To further validate this conclusion, we draw the cell survival curve to calculate the α/β ratio by the clone formation experiment and then convert the fractionated radiation dose into an equivalent single hypofractionated radiation dose comparing with that on the survival curve. Western Blot and laser confocal immunofluorescence were used to detect the expression of γ-H2AX and RAD51 after different fractionated modes of radiation. We constructed a murine xenograft model, and changes in transplanted tumor volume were used to evaluate the biological effects after different fractionated radiation. The results demonstrated that when fractionated radiation dose was converted into equivalent single hypofractionated radiation dose, the effectiveness of hypofractionated radiation was overestimated. If a larger α/β ratio was used, the discrepancy tended to become smaller. γ-H2AX was higher in 24h after a single high dose radiation than the continuous expression of the DNA repair marker RAD51. This implies more irreparable damage in a single high dose radiation compared with fractionated radiation. In the murine xenograft model, the effectiveness of hypofractionated radiation was also overestimated, and additional fractions of irradiation may be required. The conclusion is that after single hypofractionated radiation, the irreparable damage in cells increased (α value increased) and some repairable sublethal damage (β value) was converted into irreparable damage (α value). When α value increased and β value decreased, the ratio increased.

Sucupira oleoresin-based doxorubicin pH-sensitive nanoemulsions: A potential nanomedicine approach to enhance the safety profile and anticancer activity

Plant derivatives-based nanocarriers as a matrix for delivery of chemotherapeutic drugs are capable of enhancing conventional antitumor drugs' cytotoxicity against cancer cells. Bearing in mind that the use of doxorubicin-loaded sucupira oleoresin nanoemulsions can play a significant role in increasing specificity, and efficacy, whilst improvement the chemotherapy safety profile we hypothesize that this nanocarrier may be a powerful alternative strategy for cancer therapy. Thus, the aimed of this research was to prepare and characterize this nanoemulsion, as well as assess the antitumor activity and toxicity in an experimental murine breast cancer model. In the first place, the phytocompounds present in sucupira oleoresin were identified by Liquid chromatography docked Orbitrap-mass spectrometer. Afterward, the doxorubicin-loaded sucupira oleoresin nanoemulsion was prepared using hot homogenization followed by ultrasonic calibration method. Then, nanoemulsions were characterized in terms of mean diameter, polydispersity, zeta potential, entrapment efficiency, and kinetic release. Toxicity and in vivo antitumor activity were also evaluated. The bioactive compounds found in sucupira oleoresin were terpenes, especially sesqui- and vouacapan diterpenes, which have a wide range of biological activities. The sucupira oleoresin nanoemulsions with or without doxorubicin were stable under refrigeration, monodisperse featuring an average size of around 60 nm, and negative zeta potential. High encapsulation doxorubicin content (98 %) was related to the ion-pair formed between doxorubicin and oleic acid. Stability studies in different biological media suggest that the proposed formulation can remain stable after intravenous administration. Meanwhile, the release outcomes indicate a pH-responsive profile. In vivo studies show that nanoemulsions with a combination of doxorubicin and oleoresin exhibit better efficacy and reduced effects on organs of potential toxicity such as the liver, heart, and intestine as well as less body weight loss likened to the free drug. Owing to promising results, we highlight that the doxorubicin-loaded sucupira oleoresin nanoemulsion could supply gain better insights for the combined breast cancer treatment.

Genes Related to Motility in an Ionizing Radiation and Estrogen Breast Cancer Model

Breast cancer is a major global health concern as it is the primary cause of cancer death for women. Environmental radiation exposure and endogenous factors such as hormones increase breast cancer risk, and its development and spread depend on cell motility and migration. The expression of genes associated with cell motility, such as ADAM12, CYR61, FLRT2, SLIT2, VNN1, MYLK, MAP1B, and TUBA1A, was analyzed in an experimental breast cancer model induced by radiation and estrogen. The results showed that TUBA1A, SLIT2, MAP1B, MYLK, and ADAM12 gene expression increased in the irradiated Alpha3 cell line but not in the control or the malignant Tumor2 cell line. Bioinformatic analysis indicated that FLERT2, SLIT2, VNN1, MAP1B, MYLK, and TUBA1A gene expressions were found to be higher in normal tissue than in tumor tissue of breast cancer patients. However, ADAM12 and CYR61 expressions were found to be higher in tumors than in normal tissues, and they had a negative correlation with ESR1 gene expression. Concerning ESR2 gene expression, there was a negative correlation with CYR61, but there was a positive correlation with FLRT2, MYLK, MAP1B, and VNN1. Finally, a decreased survival rate was observed in patients exhibiting high expression levels of TUBA1A and MAP1B. These genes also showed a negative ER status, an important parameter for endocrine therapy. The genes related to motility were affected by ionizing radiation, confirming its role in the initiation process of breast carcinogenesis. In conclusion, the relationship between the patient’s expression of hormone receptors and genes associated with cell motility presents a novel prospect for exploring therapeutic strategies.

The Effects of Mesenchymal Stem Cells Loaded with Oncolytic Coxsackievirus A21 on Mouse Models of Colorectal Cancer.

Cancer is a major cause of death worldwide. Colorectal cancer is the second most common type. Additional treatments like chemotherapy and radiation therapy may be recommended. Developing new techniques is vital due to drug resistance and a lack of targeted therapies. In this study, the effects of mesenchymal stem cells (MSCs) loaded with oncolytic Coxsackievirus A21 (CVA21) on a mouse model of CRC were investigated. The therapeutic potency of MSCs loaded with oncolytic CVA21 were evaluated in an experimental mouse model of colorectal cancer which received an injection CT26 cells per mouse subcutaneously. Splenocyte proliferation index, lactate dehydrogenase (LDH) assay, nitric oxide (NO) production assessment, and cytokine assay (IFN-γ, IL-4, IL-10, and TGF-β) in the splenocyte supernatant were all used to evaluate the impact of MSCs loaded with CVA21. The results of this study showed that the treatment of a mouse model of colorectal cancer with MSCs loaded with oncolytic CVA21 could significantly suppress the tumor growth, which was accompanied by stimulation of splenocytes proliferation index, an increase of NO and LDH. Also, MSCs loaded with oncolytic CVA21 increased the secretion of IFN-γ and decreased the secretion of IL-4, IL-10, and TGF-β. The results of the current study suggest that MSCs loaded with oncolytic CVA21 therapy for the CRC mouse model may have some potential advantages. On the other hand, the results of the study showed that, in addition to activating the acquired immune system, the use of MSCs loaded with oncolytic CVA21 also stimulates the innate immune system by increasing level of nitric oxide.

Association of Inflammation and Immune Cell Infiltration with Estrogen Receptor Alpha in an Estrogen and Ionizing Radiation-Induced Breast Cancer Model.

Breast cancer is the most diagnosed cancer in the world, and it is the primary cause of cancer death for women. The risk of breast cancer is increased by endogenous factors like hormones and exogenous factors like radiation exposure that causes damage to the mammary epithelial cells leading to an inflammatory response. Chronic inflammation creates a microenvironment composed of, among other factors, chemokines, and interleukins, which promote cancer. The gene expression of the interleukin 1 receptor type 1, the interleukin 1 receptor antagonist, the Interleukin 1 Receptor Accessory Protein, the interleukin 6 cytokine family signal transducer, the C-X-C motif chemokine ligand 3, the C-X-C motif chemokine ligand 5, and the C-X-C motif chemokine ligand 6 were analyzed in an estrogen and radiation experimental breast cancer model. Furthermore, the expression of these genes was correlated with immune cell infiltration, estrogen receptor expression, and their clinical relevance in breast cancer patients based on data provided by The Cancer Genome Atlas database online. Results given by the experimental breast cancer model showed that all genes related to inflammation respond to ionizing radiation alone or in combination with estrogen. On the other hand, the immune response depended on the breast cancer type and on the expression of the gene that encoded the estrogen receptor. Finally, the importance of the expression of these genes in breast cancer is such that high IL1R1 or IL1RAP is strongly related to patient survival. These findings may help to improve the understanding of the role of immune molecules in carcinogenesis and enhance therapeutic approaches.

NT157 as an Anticancer Drug Candidate That Targets Kinase- and Phosphatase-Mediated Signaling

Cancer, characterized by uncontrolled cell growth and metastasis, represents a significant challenge to public health. The IGF1/IGF1R axis plays a pivotal role in tumor proliferation and survival, presenting an attractive target for intervention. NT157, a small molecule tyrphostin, has emerged as a promising inhibitor of this axis, displaying potent antineoplastic effects across various cancer types. This review synthesizes the literature on NT157’s mechanism of action and its impact on cellular processes in experimental cancer models. Initially identified for inducing the serine phosphorylation of IRS1 and IRS2, leading to their degradation and inhibiting the IGF1R signaling cascade, subsequent studies revealed additional targets of NT157, including STAT3, STAT5, and AXL, suggesting a multifaceted mechanism. Experimental evidence demonstrates that NT157 effectively suppresses tumor growth, metastasis, and angiogenesis in diverse cancer models. Additionally, NT157 enhances chemotherapy efficacy in combination therapy. Moreover, NT157 impacts not only tumor cells but also the tumor microenvironment, modulating inflammation and immune responses by targeting cancer-associated fibroblasts, myeloid cells, and immune cells, creating a suppressive milieu hindering tumor progression and metastasis. In conclusion, NT157 exhibits remarkable versatility in targeting multiple oncogenic pathways and hallmarks of cancer, underscoring its potential as a promising therapeutic agent.

Abstract IA001: Cellular and molecular underpinnings of field cancerization and progression to invasive carcinoma in bladder cancer

Abstract Two major concerns in clinical management of bladder cancer are: (i) the high frequency of recurrence; and (ii) the morbidity and mortality associated with progression to invasive disease (invasive urothelial carcinoma, IUC). To gain a better understanding of these issues we have used the murine BBN (N-butyl-N-(4-hydroxylbutyl) nitrosamine) experimental model of bladder cancer, as well as tissue samples from normal human bladders and from bladders of patients at various stages of bladder cancer formation and progression. We have documented in the BBN model a CIS-like stage, prior to invasion, in which clonal expansion from a single cell occupies a significant fraction of the urothelium. With this experimental murine model alongside observations from patient samples and data from The Cancer Genome Atlas (TCGA), we have ascertained that a key event in progression of pre-invasive to invasive carcinoma is the silencing of the Sonic hedgehog (Shh) member of the Hedgehog gene family. Silencing-associated invasion appears due to the loss of SHH-induced differentiation signals, which when present slow growth and block invasion. Despite the consistent loss of SHH expression in invasive murine and human bladder cancers, however, TCGA data show few if any mutations in the SHH gene of IUC cells. Instead, our studies of patient samples and cancer-derived cell lines reveal that the loss of SHH expression is due to tighter chromosomal packaging and reduced accessibility of a bladder-specific enhancer located ~200 kb upstream of the SHH transcription start site. We have found that inhibitors of certain chromatin-modifying enzymes, including an FDA-approved drug, are capable of re-activating SHH expression, and are testing the possibility that these drugs may block or reverse invasion of urothelial carcinoma. The high frequency of bladder cancer recurrence is thought to result from field cancerization, that is, an increased probability of new cancer formation in apparent normal urothelium, even after successful resection of the primary tumor. To understand the basis for this field effect, we compared apparent normal urothelium from cancer patients to truly normal urothelium from bladders never affected by malignancy. We found that apparent normal samples display a dramatically increased basal character in transcriptomic assays, using as a metric of basalization an index constructed from single cell RNA-seq analysis of normal urothelium. We and others have demonstrated previously by lineage tracing and cell ablation studies in the BBN model that IUC arises from basal stem cells of the urothelium. The basalization of urothelium distant from the primary tumor that we observe thus may account for the increased probability of cancer formation in the apparent normal urothelium of bladder cancer patients. We have found that several FDA-approved antagonists of EGF signaling can reverse this basalization in the mouse BBN model as well as in organoid culture, and that these drugs dramatically reduce the formation of tumors following BBN exposure. Citation Format: Philip A. Beachy, Kris B. Prado, Aaron M. Kershner, Karim Mrouj, Bernard M. Kiss, Hua Dong, Ozgu Aydogdu, Ye Tian, Joseph C. Liao. Cellular and molecular underpinnings of field cancerization and progression to invasive carcinoma in bladder cancer [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr IA001.

Lonidamine Induced Selective Acidification and De-Energization of Prostate Cancer Xenografts: Enhanced Tumor Response to Radiation Therapy.

Prostate cancer is a multi-focal disease that can be treated using surgery, radiation, androgen deprivation, and chemotherapy, depending on its presentation. Standard dose-escalated radiation therapy (RT) in the range of 70-80 Gray (GY) is a standard treatment option for prostate cancer. It could be used at different phases of the disease (e.g., as the only primary treatment when the cancer is confined to the prostate gland, combined with other therapies, or as an adjuvant treatment after surgery). Unfortunately, RT for prostate cancer is associated with gastro-intestinal and genitourinary toxicity. We have previously reported that the metabolic modulator lonidamine (LND) produces cancer sensitization through tumor acidification and de-energization in diverse neoplasms. We hypothesized that LND could allow lower RT doses by producing the same effect in prostate cancer, thus reducing the detrimental side effects associated with RT. Using the Seahorse XFe96 and YSI 2300 Stat Plus analyzers, we corroborated the expected LND-induced intracellular acidification and de-energization of isolated human prostate cancer cells using the PC3 cell line. These results were substantiated by non-invasive 31P magnetic resonance spectroscopy (MRS), studying PC3 prostate cancer xenografts treated with LND (100 mg/kg, i.p.). In addition, we found that LND significantly increased tumor lactate levels in the xenografts using 1H MRS non-invasively. Subsequently, LND was combined with radiation therapy in a growth delay experiment, where we found that 150 µM LND followed by 4 GY RT produced a significant growth delay in PC3 prostate cancer xenografts, compared to either control, LND, or RT alone. We conclude that the metabolic modulator LND radio-sensitizes experimental prostate cancer models, allowing the use of lower radiation doses and diminishing the potential side effects of RT. These results suggest the possible clinical translation of LND as a radio-sensitizer in patients with prostate cancer.

Abstract 726: The retinoid X receptor agonist MSU42011 enhances efficacy of anti-PD1 therapy in a HER2+ breast cancer model through a CD4-IL12 axis

Abstract Immunotherapy is rarely effective in breast cancer and most current therapeutic options fail to target the stromal compartment. We have developed a new small molecule, MSU42011, that induces tumor regression in experimental models of Kras-driven lung cancer and HER2+ breast cancer. This tumor regression is dependent on a functional immune system. Here, we dissected the tumor stroma, revealing a CD4 and IL12a dependency for the anti-tumor activity of MSU42011. Cancer immunotherapy responses are mostly driven by CD8 T cells. Using a murine HER2+ tumor model, anti-CD8 antibodies (200ug/mouse) were injected 24 hours before treatment with MSU42011 (100MG/KG in power diet) was started. Mice were maintained on diet for 10 days. Anti-CD8 antibodies were also administered on days 3, 7 and 10. The combination did not affect the inhibition of tumor growth by MSU42011, suggesting that its anti-tumor efficacy is not dependent on CD8 T cells. In contrast, tumors treated with MSU42011 and anti-CD4 antibodies grew (p=0.0016 versus MSU42011 alone) at the same rate as tumors treated with control diet (p=0.0139 versus MS42011). Furthermore, anti-CD4 reversed inhibition of tumor growth by MSU42011 in a carcinogen-induced lung tumor model. Interestingly, MSU42011 increased the levels of IL12 by 4x (p=0.01) and IFN by 8x (p=0.03) compared to the controls. These data suggest that MSU42011 increased Th1 CD4 T cell polarization; the increase in IL12 was lost following CD4 T cell depletion. Following depletion of IL12a with antibodies (loading dose of 1 mg, followed by 0.5mg per mouse IP), tumors treated with the combination of MSU42011 and anti-IL12a antibodies grew at the same rate as the controls. T cell engagement with MSU42011 suggests that this small molecule is a good candidate for combination with immunotherapy. HER2+ MMTV-Neu mice with established tumors were treated with the combination of MSU42011 and anti-PD1 antibodies. Treatment with MSU42011 at 100mg/Kg of diet for 10 days, followed by anti-PD1 antibodies (200ug) twice weekly failed to increase survival. In contrast, 2 doses of anti-PD1 antibodies (300ug), followed by treatment with MSU42011 increased survival by 10 days compared to controls. The tumors in the MSU42011+anti-PD1 group initially grew rapidly, with increased redness and heat, suggesting an enhanced inflammatory response. When anti-PD1 antibodies were given at a lower loading dose (200ug and then 100ug twice weekly) followed by a higher dose of MSU42011 (300 mg/Kg of diet), survival markedly increased (p=0.052). These findings demonstrate that activation of RXR in the stroma can be used to increase the effectiveness of immunotherapy. Citation Format: Ana Sofia Leal, Karen T. Liby. The retinoid X receptor agonist MSU42011 enhances efficacy of anti-PD1 therapy in a HER2+ breast cancer model through a CD4-IL12 axis [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 726.

Activity of zinc oxide and zinc borate nanoparticles against resistant bacteria in an experimental lung cancer model.

Recent research indicates a prevalence of typical lung infections, such as pneumonia, in lung cancer patients. Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter baumannii stand out as antibiotic-resistant pathogens. Given this, there is a growing interest in alternative therapeutic avenues. Boron and zinc derivatives exhibit antimicrobial, antiviral, and antifungal properties. This research aimed to establish the effectiveness of ZnO and ZB NPs in combating bacterial infections in lung cancer cell lines. Initially, this study determined the minimal inhibitory concentration (MIC) and fractional inhibitory concentration (FIC) of zinc oxide nanoparticles (ZnO NPs) and zinc borate (ZB) on chosen benchmark strains. Subsequent steps involved gauging treatment success through a lung cancer-bacteria combined culture and immunohistochemical analysis. The inhibitory impact of ZnO NPs on bacteria was charted as follows: 0.97µg/mL for K. pneumoniae 700603, 1.95µg/mL for P. aeruginosa 27853, and 7.81µg/mL for Acinetobacter baumannii 19,606. In comparison, the antibacterial influence of zinc borate was measured as 7.81µg/mL for Klebsiella pneumoniae 700603 and 500µg/mL for both P. aeruginosa 27853 and A.baumannii 19606. After 24h, the cytotoxicity of ZnO NPs and ZB was analyzed using the MTT technique. The lowest cell viability was marked in the 500µg/mL ZB NPs group, with a viability rate of 48.83% (P < 0.001). However, marked deviations appeared at ZB concentrations of 61.5µg/mL (P < 0.05) and ZnO NPs at 125µg/mL. A synergistic microbial inhibitory effect was observed when ZnO NP and ZB were combined against the bacteria under investigation.

The role of bidirectional communication between the adipokines and the endogenous opioid system in an experimental mouse model of colitis-associated colorectal cancer.

Colorectal cancer (CRC) is one of the leading causes of death globally. Multiple factors may contribute to the pathogenesis of CRC, including the abnormalities in the functioning of the endogenous opioid system (EOS) or adiponectin-related signaling. The aim of our study was to evaluate if differences in the expression of opioid receptors (ORs) influence the development of CRC and if modulation of adiponectin receptors using AdipoRon, a selective AdipoR1 receptor agonist, affects colorectal carcinogenesis. Naltrexone, an opioid receptor antagonist, was injected intraperitoneally every second day for 2weeks, at the dose of 1mg/kg in healthy Balb/C mice to induce changes in ORs expression. CRC was induced by a single intraperitoneal injection of azoxymethane (AOM) and the addition of dextran sodium sulfate (DSS) into drinking water in three-week cycles. The development of CRC was assessed using macro- and microscopic scoring and molecular analysis (RT qPCR, ELISA)after 14 weeks. Naltrexone significantly increased the mRNA expression of Oprm1, Oprd1, and Oprk1 in the mouse colon and in the brain (non-significantly). The pretreatment of mice with naltrexone aggravated the course of CRC (as indicated by tumor area, colon thickness, and spleen weight). The level of circulatory adiponectin was lowered in mice with CRC and increased in the colon as compared with healthy mice. The β-endorphin level was increased in the plasma of mice with CRC and decreased in the colon as compared to healthy mice. AdipoRon, AdipoR1 agonist, worsened the CRC development, and pretreatment with naltrexone enhanced this negative effect in mice. CRC did not affect the expression of the Adipor1 gene, but the Adipor1 level was increased in mice pretreated with naltrexone (AOM/DSS and healthy mice). AdipoRon did not influence the expression of opioid receptors at the mRNA level in the colon of mice with CRC. The mRNA expression of Ptgs2, Il6, Nos2, Il1b, Il18, Gsdmd, and Rela was increased in mice with CRC as compared to the healthy colon. AdipoRon significantly decreased mRNA expression of Ptgs2, Il6, Il1b, and Il18 as compared to CRC mice. EOS and adiponectin-related signaling may play a role in the pathogenesis of CRC and these systems may present some additivity during carcinogenesis.

Tumor-educated Gr1+CD11b+ cells drive breast cancer metastasis via OSM/IL-6/JAK-induced cancer cell plasticity.

Cancer cell plasticity contributes to therapy resistance and metastasis, which represent the main causes of cancer-related death, including in breast cancer. The tumor microenvironment drives cancer cell plasticity and metastasis, and unraveling the underlying cues may provide novel strategies for managing metastatic disease. Using breast cancer experimental models and transcriptomic analyses, we show that stem cell antigen-1 positive (SCA1+) murine breast cancer cells enriched during tumor progression and metastasis had higher in vitro cancer stem cell-like properties, enhanced in vivo metastatic ability, and generated tumors rich in Gr1hiLy6G+CD11b+ cells. In turn, tumor-educated Gr1+CD11b+ (Tu-Gr1+CD11b+) cells rapidly and transiently converted low metastatic SCA1- cells into highly metastatic SCA1+ cells via secreted oncostatin M (OSM) and IL-6. JAK inhibition prevented OSM/IL-6-induced SCA1+ population enrichment, while OSM/IL-6 depletion suppressed Tu-Gr1+CD11b+-induced SCA1+ population enrichment in vitro and metastasis in vivo. Moreover, chemotherapy-selected highly metastatic 4T1 cells maintained high SCA1+ positivity through autocrine IL-6 production, and in vitro JAK inhibition blunted SCA1 positivity and metastatic capacity. Importantly, Tu-Gr1+CD11b+ cells invoked a gene signature in tumor cells predicting shorter overall survival (OS), relapse-free survival (RFS), and lung metastasis in breast cancer patients. Collectively, our data identified OSM/IL-6/JAK as a clinically relevant paracrine/autocrine axis instigating breast cancer cell plasticity and triggering metastasis.

Metronomic cyclophosphamide and metformin inhibited tumor growth and repopulated tumor-infiltrating lymphocytes in an experimental carcinoma model

Metformin is a widely used antidiabetic biguanide. Retrospective data demonstrated the association of metformin use with survival benefit in multiple tumor types. Interest in repurposing metformin to treat cancer has not been translated into encouraging clinical benefit. In animal models, metformin activated cytotoxic T cells and exerted an immune-mediated anticancer effect. The current research was conducted to investigate the possible therapeutic benefit of metformin in combination with metronomic cyclophosphamide in an experimental cancer model. Ehrlich ascites carcinoma was injected into the subcutaneous tissue to induce solid tumors in syngeneic mice. Exponential solid tumor growth ensued and was effectively arrested with the administration of a cytotoxic dose of parenteral cyclophosphamide. Alternatively, oral metformin and continuous, low-dose cyclophosphamide significantly inhibited tumor growth relative to untreated mice. The drug combination was well tolerated. Histopathological examination of the tumor showed an increased number of tumor-infiltrating lymphocytes and enhanced expression of granzyme B by this drug combination. The current data suggests a potential role of metformin and metronomic chemotherapy that warrants further investigation.

Innervation density and types of nerves in prostate cancer.

Innervation of cancerous tissue represents an important pathway enabling the nervous system to influence the processes associated with the initiation, progression, and metastasis of a neoplastic process. In the context of prostate cancer, several papers report the presence of innervation and its modulating effect on the cancer prognosis. However, most of the data are experimental, with limited information on human prostate cancer innervation. Morphometric analysis of archival prostate specimen immunohistochemistry with neural markers PGP9.5 and S100 showed a significant decrease of nerve density in the prostate cancer (n=44) compared to the normal prostate tissue (n=18) and benign prostatic hyperplasia (n=28). Sympathetic nerves were detected with TH, parasympathetic with VAChT, and sensory nerves with SP and CGRP protein detection. Dual immunofluorescence revealed numerous sympathetic nerves in normal prostate and benign prostatic hyperplasia, especially in the peripheral parts. Only a few parasympathetic nerves were found between the glands and in the peripheral parts of the prostate and benign hyperplasia. Sporadic positivity for sensory innervation was present only in approximately 1/10 of nerve fibers, especially in the larger nerves. The pattern of innervation in prostate cancer was analogous to that in normal prostate gland and benign prostatic hyperplasia but there was a significantly lower amount of all nerve types, especially in high-grade carcinoma cases. Although not significant, there was a tendency of decreasing innervation density with increasing Gleason score. Regarding the low density of nerves in prostate carcinoma, the significantly lower PCNA counts in nerves of the cancer specimens cannot be ascribed to lower proliferation activity. Our data confirmed the lower nerve density in the prostate cancer compared to the benign prostate tissue. We could not approve an increased nerve proliferation activity in prostate cancer. All nerve types, most the sympathetic, less the parasympathetic, and the sensory nerves, are present in prostate cancer. The highest nerve density at the periphery of the cancer tissue implies this to be the result of an expansive tumor growth. It is evident that the results of experimental prostate cancer models can be applied to human pathology only to a certain extent. The relation between the range of innervation and the biology of prostate cancer is very complex and will require more detailed information to be applied in therapeutic solutions.

Body weight gain and control: beneficial effect of extra virgin olive oil versus corn oil in an experimental model of mammary cancer

Obesity is a known risk factor for breast cancer, the most common malignancy among women worldwide. We have previously described different effects of high-fat diets on mammary experimental carcinogenesis. In this work, we analyzed the animal growth data obtained in six experimental assays, in healthy and carcinogen-induced rats undergoing different dietary interventions. The animals were fed with three experimental diets administered at different periods of development: a control low-fat diet, and two isocaloric high-fat diets (rich in corn oil or in extravirgin olive oil -EVOO-). Weekly weight throughout the development of 818 animals have been compiled and reanalyzed using adjusted mathematical models. Molecular mechanisms have been investigated: ethanolamides in small intestine, neuropeptides controlling satiety in hypothalamus, and proteins controlling lipid metabolism in adipose and mammary tissues. The results indicated that the effect of diets depended on type of lipid, timing of intervention and health status. The high corn oil diet, but not the high EVOO diet, increased body weight and mass, especially if administered from weaning, in healthy animals and in those that received a moderate dose of carcinogen. The potential protective effect of EVOO on weight maintenance may be related to anorexigenic neuropeptides such as oxytocin and lipolysis/deposition balance in adipose tissue (increasing phospho-PKA, HSL, MGL and decreasing FAS). In animals with cancer, body weight gain was related to the severity of the disease. Taken together, our results suggest that EVOO has a beneficial effect on body weight maintenance in both health and cancer.

Disseminating cells in human oral tumours possess an EMT cancer stem cell marker profile that is predictive of metastasis in image-based machine learning.

Cancer stem cells (CSCs) undergo epithelial-mesenchymal transition (EMT) to drive metastatic dissemination in experimental cancer models. However, tumour cells undergoing EMT have not been observed disseminating into the tissue surrounding human tumour specimens, leaving the relevance to human cancer uncertain. We have previously identified both EpCAM and CD24 as CSC markers that, alongside the mesenchymal marker Vimentin, identify EMT CSCs in human oral cancer cell lines. This afforded the opportunity to investigate whether the combination of these three markers can identify disseminating EMT CSCs in actual human tumours. Examining disseminating tumour cells in over 12,000 imaging fields from 74 human oral tumours, we see a significant enrichment of EpCAM, CD24 and Vimentin co-stained cells disseminating beyond the tumour body in metastatic specimens. Through training an artificial neural network, these predict metastasis with high accuracy (cross-validated accuracy of 87-89%). In this study, we have observed single disseminating EMT CSCs in human oral cancer specimens, and these are highly predictive of metastatic disease.

Capsaicinoids and Their Effects on Cancer: The "Double-Edged Sword" Postulate from the Molecular Scale.

Capsaicinoids are a unique chemical species resulting from a particular biosynthesis pathway of hot chilies (Capsicum spp.) that gives rise to 22 analogous compounds, all of which are TRPV1 agonists and, therefore, responsible for the pungency of Capsicum fruits. In addition to their human consumption, numerous ethnopharmacological uses of chili have emerged throughout history. Today, more than 25 years of basic research accredit a multifaceted bioactivity mainly to capsaicin, highlighting its antitumor properties mediated by cytotoxicity and immunological adjuvancy against at least 74 varieties of cancer, while non-cancer cells tend to have greater tolerance. However, despite the progress regarding the understanding of its mechanisms of action, the benefit and safety of capsaicinoids' pharmacological use remain subjects of discussion, since CAP also promotes epithelial-mesenchymal transition, in an ambivalence that has been referred to as "the double-edge sword". Here, we update the comparative discussion of relevant reports about capsaicinoids' bioactivity in a plethora of experimental models of cancer in terms of selectivity, efficacy, and safety. Through an integration of the underlying mechanisms, as well as inherent aspects of cancer biology, we propose mechanistic models regarding the dichotomy of their effects. Finally, we discuss a selection of in vivo evidence concerning capsaicinoids' immunomodulatory properties against cancer.

Graviola Protects Against Hepatic Toxicity Associated with DMBA induced Breast Cancer via Restoration of Antioxidants and Attenuation of Inflammatory Pathways

Aims: This study documented hepatic tissue's protective activity against oxidative damage mediated experimental models of breast cancer. Background: Gaviola has a long history of improving the protection mechanism against many diseases as an antioxidant and anticancer dietary agent. Objective: The purpose of this study is to establish changes in hepatic profiling, antioxidants, inflammatory cytokine expression, and DMBA-induced hepatic histopathology of mammalian rats. Methods: 7,12-dimethylbenz[a] anthracene (DMBA), PAHs, used orally in female Sprague Dawley rats Fifty-seven days-old with breast cancer single-dose diluted in sesame oil of 20 mg/kg/body weight. The cancer-bearing animals had 45 days gastrogavagated at 200 mg/kg/body weight with Graviola. The serum samples were taken at the end of the experiment. The rats were sacrificed to establish the hepatic protective activity of the Graviola by testing hepatic and oxidative stress markers. Results: Graviola therapy shows that enzymatic and non-enzymatic antioxidants and lipid peroxide levels have increased efficiency and have restored the high activity of hepatic marker enzymes such as ALT, AST, ALP, and GGT. To date, hepatic expression of nuclear factor erythroid 2-like 2 (Nfe2l2) and nuclear factor kappa B subunit 1 (Nfkb1) mediated rats have normalized. In addition, histological observations have demonstrated that Graviola's treatment effectively protects the liver from the oxidative damage caused by DMBA, reinforcing its hepatic defensive nature. Conclusion: Graviola therapy improves the efficiency of both enzymatic and non-enzymatic antioxidants and lipid peroxide levels. It also helps in the restoration of other liver enzymes.

GK-1 effectively reduces angiogenesis and prevents T cell exhaustion in a breast cancer murine experimental model

Breast cancer is the leading malignancy in women worldwide, both in terms of incidence and mortality. Triple-negative breast cancer (TNBC) is the type with the worst clinical outcomes and with fewer therapeutic options than other types of breast cancer. GK-1 is a peptide that in the experimental model of the metastatic 4T1 breast cancer has demonstrated anti-tumor and anti-metastatic properties. Herein, GK-1 (5 mg/kg, i.v.) weekly administrated not only decreases tumor growth and the number of lung macro-metastases but also lung and lymph nodes micro-metastases. Histological analysis reveals that GK-1 reduced 57% of the intra-tumor vascular areas, diminished the leukemoid reaction's progression, and the spleens' weight and length. A significant reduction in VEGF-C, SDF-1, angiopoietin-2, and endothelin-1 angiogenic factors was induced. Moreover, GK-1 prevents T cell exhaustion in the tumor-infiltrating lymphocytes (TILs) decreasing PD-1 expression. It also increased IFN-γ and granzyme-B expression and the cytotoxic activity of CD8+ TILs cells against tumor cells. All these features were found to be associated with a better antitumor response and prognosis. Altogether, these results reinforce the potential of GK-1 to improve the clinical outcome of triple-negative breast cancer immunotherapy. Translation research is ongoing towards its evaluation in humans.

Overview of research progress and application of experimental models of colorectal cancer.

Colorectal cancer (CRC) is the third most common malignancy in terms of global tumor incidence, and the rates of morbidity and mortality due to CRC are rising. Experimental models of CRC play a vital role in CRC research. Clinical studies aimed at investigating the evolution and mechanism underlying the formation of CRC are based on cellular and animal models with broad applications. The present review classifies the different experimental models used in CRC research, and describes the characteristics and limitations of these models by comparing the research models with the clinical symptoms. The review also discusses the future prospects of developing new experimental models of CRC.