miR155 deficiency reduces breast tumor burden in the MMTV-PyMT mouse model.

miRNA155 (miR155) has emerged as an important regulator of breast cancer (BrCa) development. Studies have consistently noted an increase in miR155 levels in serum and/or tissues in patients with BrCa. However, what is less clear is whether this increase in miR155 is a reflection of oncogenic or tumor suppressive properties.

Impact of weight loss and partial weight regain on immune cell and inflammatory markers in adipose tissue in male mice.

Weight fluctuations are common among individuals with obesity and are associated with increased morbidity. We examined adipose tissue immune and inflammatory markers in mice following weight loss and partial weight regain. Male C57BL/6 mice were randomized into four groups ( = 8-10/group): low-fat diet for 32 wk (LFD), high-fat diet for 32 wk (HFD), LFD for 28 wk and then changed to a HFD for 4 wk (LFD→H), and HFD for 21 wk and then changed to LFD for 7 wk and then changed to HFD for 4 wk (HFD→L→H).

Effects of high fat diet-induced obesity on mammary tumorigenesis in the PyMT/MMTV murine model.

Clinical studies provide strong evidence that obesity and associated adipose tissue (AT) inflammation are risk factors for breast cancer (BrCA); however, mechanistic knowledge of the interaction of obesity, BrCA, and menopausal status has proven to be not only lacking, but contradictory. Obesity-induced inflammation and elevated biosynthesis of estrogens, through aromatase-mediated metabolism of precursors, have been linked with hormone receptor positive (HP) postmenopausal BrCA but not previously associated with premenopausal BrCA risk. Thus, further delineation of the interaction of obesity, inflammation, and aromatase is required for the development of therapeutic treatment options.

miR155 deficiency aggravates high-fat diet-induced adipose tissue fibrosis in male mice.

Noncoding RNAs are emerging as regulators of inflammatory and metabolic processes. There is evidence to suggest that miRNA155 (miR155) may be linked to inflammation and processes associated with adipogenesis. We examined the impact of global miRNA-155 deletion (miR155) on the development of high-fat diet (HFD)-induced obesity.

Loss of monocyte chemoattractant protein-1 expression delays mammary tumorigenesis and reduces localized inflammation in the C3(1)/SV40Tag triple negative breast cancer model.

Monocyte chemoattractant protein 1 (MCP-1) has been implicated as a major modulator in the progression of mammary tumorigenesis, largely due to its ability to recruit macrophages to the tumor microenvironment. Macrophages are key mediators in the connection between inflammation and cancer progression and have been shown to play an important role in tumorigenesis. Thus, MCP-1 may be a potential therapeutic target in inflammatory and difficult-to-treat cancers such as triple negative breast cancer (TNBC).

Weight loss following diet-induced obesity does not alter colon tumorigenesis in the AOM mouse model.

Obesity presents a significant public health concern given its association with increased cancer incidence, unfavorable prognosis, and metastasis. However, there is very little literature on the effects of weight loss, following obesity, on risk for colon cancer or liver cancer. Therefore, we sought to study whether intentional weight loss through diet manipulation was capable of mitigating colon and liver cancer in mice.

High-fat diets rich in saturated fat protect against azoxymethane/dextran sulfate sodium-induced colon cancer.

High-fat-diet (HFD) consumption is associated with colon cancer risk. However, little is known about how the lipid composition of a HFD can influence prooncogenic processes. We examined the effects of three HFDs differing in the percentage of total calories from saturated fat (SF) (6, 12, and 24% of total caloric intake), but identical in total fat (40%), and a commercially available Western diet (26 and 41% saturated and total fat, respectively) on colon cancer development using the azoxymethane (AOM)/dextran sulfate sodium (DSS) murine model.

MicroRNA-155 deletion promotes tumorigenesis in the azoxymethane-dextran sulfate sodium model of colon cancer.

Clinical studies have linked microRNA-155 (miR-155) expression in the tumor microenvironment to poor prognosis. However, whether miR-155 upregulation is predictive of a pro- or antitumorigenic response is unclear, as the limited preclinical data available remain controversial. We examined miR-155 expression in tumor tissue from colon cancer patients.

Lowering the dietary omega-6: omega-3 does not hinder nonalcoholic fatty-liver disease development in a murine model.

It is hypothesized that a high dietary n-6:n-3 (eg, 10-20:1) is partly responsible for the rise in obesity and related health ailments. However, no tightly controlled studies using high-fat diets differing in the n-6:n-3 have tested this hypothesis. The aim of the study was to determine the role that the dietary n-6:n-3 plays in non-alcoholic fatty-liver disease (NAFLD) and colitis development.

Limbal squamous cell carcinoma in Haflinger horses.

Objective: To describe the prevalence of LSCC in Haflinger horses and to analyze affected horses' pedigrees investigating the genetic mode of inheritance.

Animals: Fifteen horses met inclusion criterion of (i) being of the Haflinger breed, as confirmed by North American Haflinger Registry pedigree and (ii) being diagnosed with LSCC, as confirmed by clinical examination by a veterinary ophthalmologist or by histopathology. Pedigrees could not be obtained for four additional horses diagnosed with LSCC that had been identified as Haflingers.

Reducing the dietary omega-6:omega-3 utilizing α-linolenic acid; not a sufficient therapy for attenuating high-fat-diet-induced obesity development nor related detrimental metabolic and adipose tissue inflammatory outcomes.

Aims: To examine the effect of manipulating the omega-6:omega-3 (1∶1, 5∶1, 10∶1, and 20∶1) utilizing only α-linolenic and linoleic acid within a clinically-relevant high-fat diet (HFD) composed of up to seven sources of fat and designed to be similar to the standard American diet (MUFA∶PUFA of 2∶1, 12% and 40% of calories from saturated and total fat, respectively) on body composition, macrophage polarization, inflammation, and metabolic dysfunction in mice.

Methods: Diets were administered for 20 weeks. Body composition and metabolism (HOMA index and lipid profile) were examined monthly.