Exploring heterogeneity: a dive into preclinical models of cancer cachexia.

Cancer cachexia (CC) is a multifactorial and complex syndrome experienced by up to 80% of patients with cancer and implicated in ∼40% of cancer-related deaths. Given its significant impact on patients' quality of life and prognosis, there has been a growing emphasis on elucidating the underlying mechanisms of CC using preclinical models. However, the mechanisms of cachexia appear to differ across several variables including tumor type and model and biologic variables such as sex. These differences may be exacerbated by variance in experimental approaches and data reporting. This review examines literature spanning from 2011 to March 2024, focusing on common preclinical models of CC, including Lewis Lung Carcinoma, pancreatic KPC, and colorectal colon-26 and Apcmin/+ models. Our analysis reveals considerable heterogeneity in phenotypic outcomes, and investigated mechanisms within each model, with particular attention to sex differences that may be exacerbated through methodological differences. Although searching for unified mechanisms is critical, we posit that effective treatment approaches are likely to leverage the heterogeneity presented by the tumor and pertinent biological variables to direct specific interventions. In exploring this heterogeneity, it becomes critical to consider methodological and data reporting approaches to best inform further research.

Effect of vitamin E δ-tocotrienol and aspirin on Wnt signaling in human colon cancer stem cells and in adenoma development in APCmin/+ mice.

In this study, we evaluated the effects of vitamin E δ-tocotrienol (DT3) and aspirin on Wnt signaling in human colon cancer stem cells (CCSCs) and in the prevention of adenoma formation in APCmin/+ mice. We found that knockdown of the adenomatous polyposis coli (APC) gene led to subsequent activation of Wnt signaling in colon epithelial cells (NCM460-APCsiRNA) and induction of ß-catenin and its downstream target proteins c-MYC, cyclin D1, and survivin. When aspirin and DT3 were combined, cell growth and survival were inhibited and apoptosis was induced in colon epithelial cells and in CCSCs. However, DT3 and/or aspirin had little or no effect on control normal colon epithelial cells (NCM460-NCsiRNA). The induction of apoptosis was directly related to activation of caspase 8 and cleavage of BID to truncated BID. In addition, DT3 and/or aspirin-induced apoptosis was associated with cleaved PARP, elevated levels of cytosolic cytochrome c and BAX, and depletion of anti-apoptotic protein BCl-2 in CCSCs. The combination of aspirin and DT3 inhibited the self-renewal capacity, Wnt/ß-catenin receptor activity, and expression of ß-catenin and its downstream targets c-MYC, cyclin D1 and survivin in CCSCs. We also found that treatment with DT3 alone or combined with aspirin significantly inhibited intestinal adenoma formation and Wnt/ ß-catenin signaling and induced apoptosis, compared to vehicle, in APCmin/+ mice. Our study demonstrated a rationale for further investigation of the combination of DT3 and aspirin for colorectal cancer prevention and therapy.

Exposure to Microcystin-LR Promotes Colorectal Cancer Progression by Altering Gut Microbiota and Associated Metabolites in APCmin/+ Mice.

Microcystins (MCs), toxins generated by cyanobacteria, feature microcystin-LR (MC-LR) as one of the most prevalent and toxic variants in aquatic environments. MC-LR not only causes environmental problems but also presents a substantial risk to human health. This study aimed to investigate the impact of MC-LR on APCmin/+ mice, considered as an ideal animal model for intestinal tumors. We administered 40 µg/kg MC-LR to mice by gavage for 8 weeks, followed by histopathological examination, microbial diversity and metabolomics analysis. The mice exposed to MC-LR exhibited a significant promotion in colorectal cancer progression and impaired intestinal barrier function in the APCmin/+ mice compared with the control. Gut microbial dysbiosis was observed in the MC-LR-exposed mice, manifesting a notable alteration in the structure of the gut microbiota. This included the enrichment of Marvinbryantia, Gordonibacter and Family_XIII_AD3011_group and reductions in Faecalibaculum and Lachnoclostridium. Metabolomics analysis revealed increased bile acid (BA) metabolites in the intestinal contents of the mice exposed to MC-LR, particularly taurocholic acid (TCA), alpha-muricholic acid (α-MCA), 3-dehydrocholic acid (3-DHCA), 7-ketodeoxycholic acid (7-KDCA) and 12-ketodeoxycholic acid (12-KDCA). Moreover, we found that Marvinbryantia and Family_XIII_AD3011_group showed the strongest positive correlation with taurocholic acid (TCA) in the mice exposed to MC-LR. These findings provide new insights into the roles and mechanisms of MC-LR in susceptible populations, providing a basis for guiding values of MC-LR in drinking water.

Combined effects of radiation and simulated microgravity on intestinal tumorigenesis in C3B6F1 ApcMin/+ mice.

Explorations of the Moon and Mars are planned as future manned space missions, during which humans will be exposed to both radiation and microgravity. We do not, however, know the health effects for such combined exposures. In a ground-based experiment, we evaluated the combined effects of radiation and simulated microgravity on tumorigenesis by performing X-irradiation and tail suspension in C3B6F1 ApcMin/+ mice, a well-established model for intestinal tumorigenesis. Mice were irradiated at 2 weeks of age and underwent tail suspension for 3 or 11 weeks using a special device that avoids damage to the tail. The tail suspension treatment significantly reduced the thymus weight after 3 weeks but not 11 weeks, suggesting a transient stress response. The combination of irradiation and tail suspension significantly increased the number of small intestinal tumors less than 2 mm in diameter as compared with either treatment alone. The combined treatment also increased the fraction of malignant tumors among all small intestinal tumors as compared with the radiation-only treatment. Thus, the C3B6F1 ApcMin/+ mouse is a useful model for assessing cancer risk in a simulated space environment, in which simulated microgravity accelerates tumor progression when combined with radiation exposure.

Astragaloside IV Ameliorates Colonic Adenomatous Polyps Development by Orchestrating Gut Bifidobacterium and Serum Metabolome.

Astragaloside IV (AS-IV), a natural triterpenoid isolated from Astragalus membranaceus, has been used traditionally in Chinese medicine. Previous studies have highlighted its benefits against carcinoma, but its interaction with the gut microbiota and effects on adenomatous polyps are not well understood. This present study investigates the effects of AS-IV on colonic adenomatous polyp (CAP) development in high-fat-diet (HFD) fed [Formula: see text] mice. [Formula: see text] mice were fed an HFD with or without AS-IV or Naringin for 8 weeks. The study assessed CAP proliferation and employed 16S DNA-sequencing and untargeted metabolomics to explore correlations between microbiome and metabolome in CAP development. AS-IV was more effective than Naringin in reducing CAP development, inhibiting colonic proinflammatory cytokines (IL-1[Formula: see text], IL-6, and TNF-[Formula: see text]), tumor associated biomarkers (c-Myc, Cyclin D1), and Wnt/[Formula: see text]-catenin pathway proteins (Wnt3a, [Formula: see text]-catenin). AS-IV also inhibited the proliferative capabilities of human colon cancer cells (HT29, HCT116, and SW620). Multiomics analysis revealed AS-IV increased the abundance of beneficial genera such as Bifidobacterium pseudolongum and significantly modulated serum levels of certain metabolites including linoleate and 2-trans,6-trans-farnesal, which were significantly correlated with the number of CAP. Finally, the anti-adenoma efficacy of AS-IV alone was significantly suppressed post pseudoaseptic intervention in HFD-fed [Formula: see text] mice but could be reinstated following a combined with Bifidobacterium pseudolongum transplant. AS-IV attenuates CAP development in HFD-fed [Formula: see text] mice by regulating gut microbiota and metabolomics, impacting the Wnt3a/[Formula: see text]-catenin signaling pathway. This suggests a potential new strategy for the prevention of colorectal cancer, emphasizing the role of gut microbiota in AS-IV's antitumor effects.

Mechanism of Baoyuan Jiedu Decoction in Alleviating Muscle Atrophy in Apcmin/+ Cachexia Mice / 中国实验方剂学杂志

Objective: To study the effect of Baoyuan Jiedu decoction on serum interleukin-6 (IL-6) content, expression of muscle atrophy F-box 1(Atrogin-1), muscle ring finger-1 (MuRF-1), uncoupling proteins-2 (UCP-2), uncoupling proteins-3 (UCP-3) in Apcmin/+ mice, in order to explore the mechanism in improving muscle atrophy in cancer cachexia model. Method: The 14-week-old Apcmin/+ cachexia mice model was randomly divided into model group, Baoyuan Jiedu decoction group (23 g·kg-1) and megestrol group (0.024 g·kg-1). C57BL/6J mice were normal group, with 10 mice in each group, and given continuous intragastric administration for 12 weeks. The quality of gastrocnemius muscle and the transverse diameter of muscle fibers were measured. The content of IL-6 in serum of Apcmin/+ cachexia mice was detected by enzyme-linked immunosorbent assay (ELISA). The expressions of Atrogin-1, MuRF-1, UCP-2, UCP-3 mRNA and protein in gastrocnemius muscle were detected by Western blot and quantitative real-time fluorescence polymerase chain reaction (Real-time PCR). Result: Compared with the normal group, the weight of gastrocnemius muscle and the transverse diameter of fibers in the model group decreased significantly (PPPPConclusion: Reduction of the concentration of IL-6 in serum and the down-regulation of the expressions of Atrogin-1, MuRF-1, UCP-2 and UCP-3 genes may be the possible mechanism of Baoyuan Jiedu decoction in alleviating muscle atrophy in Apcmin/+ cachexia mice model.

Cancer-preventive Properties of an Anthocyanin-enriched Sweet Potato in the APCMIN Mouse Model

BACKGROUND: Anthocyanin-rich foods and preparations have been reported to reduce the risk of life-style related diseases, including cancer. The SL222 sweet potato, a purple-fleshed cultivar developed in New Zealand, accumulates high levels of anthocyanins in its storage root. METHODS: We examined the chemopreventative properties of the SL222 sweet potato in the C57BL/6J-APC(MIN/+) (APC(MIN)) mouse, a genetic model of colorectal cancer. APC(MIN) and C57BL/6J wild-type mice (n=160) were divided into four feeding groups consuming diets containing 10% SL222 sweet potato flesh, 10% SL222 sweet potato skin, or 0.12% ARE (Anthocyanin rich-extract prepared from SL222 sweet potato at a concentration equivalent to the flesh-supplemented diet) or a control diet (AIN-76A) for 18 weeks. At 120 days of age, the mice were anaesthetised, and blood samples were collected before the mice were sacrificed. The intestines were used for adenoma enumeration. RESULTS: The SL222 sweet potato-supplemented diets reduced the adenoma number in the APC(MIN) mice. CONCLUSIONS: These data have significant implications for the use of this sweet potato variant in protection against colorectal cancer.

Chemopreventive Action of Anthocyanin-rich Black Soybean Fraction in APC(Min/+) Intestinal Polyposis Model

BACKGROUND: Anthocyanins have been shown to inhibit cancer cell growth by suppressing oxidative stress and inflammatory responses. The purpose of this study was to investigate the effects of an anthocyanin-rich extract (AE) from black soybean coat on intestinal carcinogenesis. METHODS: APC(Min/+) mice were fed a diet of 0.2% or 0.5% AE for 7 weeks. We analyzed the number of intestinal tumors, oxidative stress and inflammatory markers associated with beta-catenin and cytosolic phospholipase A2 (cPLA2) signals. The number of intestinal tumors, and cellular expression of beta-catenin were determined. RESULTS: The number of intestinal tumors was significantly lower in mice fed a 0.5% AE diet compared to those of the other groups. Cytosolic beta-catenin expression was significantly decreased in the AE supplemented groups compared to that of the control animals. In addition, mucosa expression of cyclooxygenase-2 and cPLA2 were also significantly decreased in the 0.5% AE group, by 32% and 62%, respectively, compared to the control group. CONCLUSIONS: These results suggest that dietary AE reduced the development of intestinal tumors, possibly through the ability to suppress oxidative stresses, decreasing inflammatory responses mediated by beta-catenin associated signals.

Secondary bile acid induced intestinal adenoma canceration and its effect on intestinal microflora in Apcmin/+ mice / 中华消化杂志

Objective To investigate secondary bile acid induced canceration process of intestinal adenoma and effects on intestinal microflora in Apcmin/+ mice.Methods Forty four-week-old mice (20 Apcmin/+mice and 20 wild-type C57BL/6J mice) were divided into four groups:wild-type control group (regular drinking water),wild-type deoxycholic acid (DOC) group (with 0.2 ％ DOC in drinking water),Apcmin/+ control group and Apcmin/+ DOC group.Fecal pellets of Apcmin/+ mice were collected at 0 week and 12 week after administration.The changes of intestinal microflora were analyzed by pyrosequencing.All mice were sacrificed after 12 weeks.The number,size and location of intestinal adenoma were observed.The pathological type of adenoma was evaluated after hematcxylin-eosin (HE) staining.Proliferating cell nuclear antigen (PCNA) was detected by immunohistochemistry.Cell apoptosis was determined by in situ terminal deoxynucleotidyl transferase mediated dUTP nick end labeling technique (TUNEL).Independent t test was used for the quantitative data comparison between two groups.Results No intestinal tumors were found in the wild-type mice.The total number of intestinal adenoma of Apcmin/+ DOC group significantly increased,compared with that of Apcmin/+ control group (57.00 ± 3.07 vs 21.50± 4.69,t=20.03,P＜0.01),the increase of the adenoma with maximum diameter between 1 to 2 mm was most significant (30.62± 7.73 vs 7.75 ± 4.59,t =8.04,P＜ 0.05),the rate of adenoma canceration also significantly increased compared with that of Apcmin/+ control group.The percentage of PCNA positive cells significantly increased compared with that of Apcmin/+ control group ((90.17 ± 2.14) ％ vs (41.97 ± 4.26) ％,t=31.97,P＜0.01).The percentage of cell apoptosis significantly declined ((1.40± 1.12) ％ vs (7.50 ± 0.65)％,t =14.90,P＜ 0.01).The diversity of intestinal flora of Apcmin/+ DOC group significantly decreased.The ratio of Firmicutes and Bacteroidetes significantly increased compared with control group (0.586 7±0.148 4 vs 0.387 3±0.013 6,t=2.36,P＜0.05).The number of pathogenic bacteria increased in Apcmin/+ DOC group and probiotics significantly decreased.Conclusion DOC can induce intestinal flora imbalance in Apcmin/+ mice and promote intestinal adenoma into adenocarcinoma through increasing tumor cell proliferation and inhibiting cell apoptosis.

Establishment of a transgenic heterozygous mouse model of ApcMin/+pre-cancerosis of colorectal cancer with p110δmutation / 中国病理生理杂志

[ABSTRACT]AIM:Toestablishatransgenicheterozygousmousemodelofprecancerouslesionsofcolorectal cancer with p110δmutation in the C57BL/6J background for serving the studies on colorectal cancer research mediated by p110δ.METHODS:The transgenic heterozygous mice were generated by crossing in p110δD910A/D910A mouse and ApcMin/+mouse, and the genotype was detected by PCR .Compared with ApcMin/+mice, transgenic heterozygous mice ( ApcMin/+;p110δD910A/D910A)were counted, and the number and size of intestine polyps were analyzed after methylene blue staining . The intestinal tissue structure was assessed by HE staining .RESULTS:The transgenic heterozygous mouse model of pre-cancerous lesions of colorectal cancer with p 110δmutation was established .The number and size of polyps in the transgenic heterozygous mice were declined .CONCLUSION: A transgenic heterozygous mouse model of precancerous lesions of colorectal cancer with p 110δmutation was successfully established .The initial phenotype of intestinal tumors in transgenic mice was observed .This model will greatly contribute to the related research of colorectal cancer in mice .

Effects of berberine on the tumor-associated macrophages of intestinal polyps in Apc (Min/+) mice / 中华消化杂志

Objective To investigate the effects of berberine on tumor-associated macrophages (TAM)and the expression of cyclooxygenase-2 (COX-2)of intestinal polyps in Apc(Min/+) mice.Methods A total of 20 Apc(Min/+) mice,four weeks old,were equally divided into the control group and the berberine group,10 in each group.The mice of the control group drank plain water,while the mice of berberine group drank water with 0.1 % berberine.After 12 weeks,all the mice were sacrificed.The intestine and colon were isolated,and the numbers of polyps were counted.The expression of F4/80,inducible nitric oxide synthase-2 (iNOS),macrophage mannose receptor (MR)and COX-2 was detected by immunohisto-chemistry method.The relative expression of COX-2 at protein level was measured by Western blotting. The t test was performed for comparison between two independent groups.Results The total number of intestinal polyps,the number of small intestinal polyps and the number of colon polyps of the berberine group (11 .50±2.05 ,10.50±1 .77 and 1 .00±0.46,respectively)were all less than those of the control group (30.63±1 .69,28.00±2.00 and 2.63±0.74,respectively),and the differences were statistically significant (t=16.727,16.952 and 3.162,P =0.001 ,0.001 and 0.010,respectively).The percentage of F4/80 positive cells in the stroma of polyps of the berberine group ((17.40 ±4.23 )%)was less than that of the control group ((31 .24±6.34)%),and the difference was statistically significant (t =5 .327, P =0.043).The percentage of iNOS positive cells in the stroma of polyps of the berberine group ((7.43± 1 .78 )%) was higher than that of the control group ((2.72±0.68)%), and the difference was statistically significant (t=7.335 ,P =0.004).The percentage of MR positive cells in stroma of polyps of the berberine group ((19.52±1 .54)%)was less than that of the control group ((12.63±0.68)%),and the difference was statistically significant (t=5 .634,P =0.016).The percentage of COX-2 positive cells in stroma of polyps of berberine group ((3.38 ± 0.51 )%)was less than that of the control group ((7.60±0.57 )%),and the difference was statistically significant (t = 7.234,P = 0.001 ).The relative expression of COX-2 at protein level of polyps of the berberine group was lower than that of the control group. Conclusion Berberine may take the role in inhibiting the growth of intestinal polyps in Apc(Min/+) mice through interfering the differentiation of TAM in polyps and suppression the expression of COX-2.

Effects of Cdc20 mutation on growth of mouse embryonic fibroblast / 解剖学报

Objective Investigation of biological characteristics of Cdc 20AAA/+APCmin/+ mouse embryonic fibroblast(MEFs) indicate the effect of Cdc20AAA/+on growth of mouse embryonic fibroblast and the possible mechanism . Methods MEFs of Cdc20AAA/+APCmin/+, Cdc20AAA/+, APCmin/+ and WT genotype were harvested from embryos for analysis.The growth characteristics of Cdc20AAA/+APCmin/+, Cdc20AAA/+,APCmin/+and WT mouse embryonic fibroblast were analyzed through growth curve analysis and foci formation assay .Separation of sister chromatid and the presence of aneuploid were detected by karyotype analysis .Results Cell proliferation assays showed that Cdc 20AAA/+APCmin/+cells grew at an accelerated rate compared with APC min/+MEFs(P<0.01).Foci formation assay showed that the clone forming ability was significantly increased .Cdc20AAA/+APCmin/+MEFs showed a significant increase in the frequency of aneuploid compared with WT MEFs , which had a karyotype of 38 and contained prematurely separated sister chromatids .Conclusion Cdc20 carrying a null allele (Cdc20AAA/+) may accelerate the growth and proliferation of APC min/+MEFs and present the growth characteristics of the tumor cells .The possible mechanism may be associated with chromosome instability .

Inhibitory effects of calcium against intestinal cancer in human colon cancer cells and ApcMin/+ mice

The aim of the study was to investigate the inhibitory effects of calcium against intestinal cancer in vitro and in vivo. We first investigated the effects of calcium treatment in HCT116 and HT29 human colon cancer cells. At the concentration range of 0.8-2.4 mM, calcium significantly inhibited cell growth (by 9-29%), attachment (by 12-26%), invasion (by 15-31%), and migration (by 19-61%). An immunofluorescence microscope analysis showed that the treatment with calcium (1.6 mM) for 24 h increased plasma membrane beta-catenin but decreased nuclear beta-catenin levels in HT29 cells. We then investigated the effect of dietary calcium on intestinal tumorigenesis in ApcMin/+ mice. Mice received dietary treatment starting at 6 weeks of age for the consecutive 8 weeks. The basal control diet contained high-fat (20% mixed lipids by weight) and low-calcium (1.4 mg/g diet) to mimic the average Western diet, while the treatment diet contained an enriched level of calcium (5.2 mg calcium/g diet). The dietary calcium treatment decreased the total number of small intestinal tumors (by 31.4%; P or = 2 mm in diameter, showing a 75.6% inhibition in the small intestinal tumor multiplicity (P < 0.001). Immunohistochemical analysis showed significantly reduced nuclear staining of beta-catenin (expressed as nuclear positivity), but increased plasma membrane staining of beta-catenin, in the adenomas from the calcium-treated groups in comparison to those from the control group (P < 0.001). These results demonstrate intestinal cancer inhibitory effects of calcium both in human colon cancer cells and Apc Min/+ mice. The decreased beta-catenin nuclear localization caused by the calcium treatment may contribute to the inhibitory action.