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Cruz-Monserrate, Z.

Publications and source records attributed to Cruz-Monserrate, Z..

4 recordsLinked to original sources

Ketogenic diet prevents obesity-associated pancreatic cancer independent of weight loss and induces pancreatic metabolic reprogramming

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive cancer with poor outcomes. Obesity is a risk factor for several cancers including PDAC due to metabolic dysregulation and inflammation. The ketogenic diet (KD) can alter metabolism and has been evaluated for its effects on tumor progression in non-obese but not obese PDAC using genetically engineered mouse models (GEMMs). We hypothesized that ketone bodies and a KD alter cell and tumor metabolism. We show that ketone treatments altered pyrimidine metabolism in PDAC cells. Moreover, in an obese PDAC GEMM, KD prevented tumor progression independent of weight loss but promoted PDAC in a non-obese PDAC GEMM. The KD-specific delay of obesity-associated PDAC was associated with pancreatic metabolic shifts in pyrimidine, cysteine and methionine, and arginine and proline pathways. These findings suggest potential benefits of a KD in preventing obesity-associated PDAC, but highlights some risks in non-obese settings.

cancer biology↗

Changes in Plasma Fatty Acid Abundance Related to Chronic Pancreatitis: A Pilot Study

ObjectivesChronic pancreatitis (CP) is an inflammatory disease that affects the absorption of nutrients like fats. Molecular signaling in pancreatic cells can be influenced by fatty acids (FAs) and changes in FA abundance could impact CP-associated complications. Here, we investigated FA abundance in CP compared to controls and explored how CP-associated complications and risk factors affect FA abundance. MethodsBlood and clinical parameters were collected from subjects with (n=47) and without CP (n=22). Plasma was analyzed for relative FA abundance using gas chromatography and compared between controls and CP. Changes in FA abundance due to clinical parameters were also assessed in both groups. ResultsDecreased relative abundance of polyunsaturated fatty acids (PUFAs) and increased monounsaturated fatty acids (MUFAs) were observed in subjects with CP in a sex-dependent manner. The relative abundance of linoleic acid increased, and oleic acid decreased in CP subjects with exocrine pancreatic dysfunction and a history of substance abuse. ConclusionsPlasma FAs like linoleic acid are dysregulated in CP in a sex-dependent manner. Additionally, risk factors and metabolic dysfunction further dysregulate FA abundance in CP. These results enhance our understanding of CP and highlight potential novel targets and metabolism-related pathways for treating CP.

physiology↗

Physical Activity Delays Obesity-Associated Pancreatic Ductal Adenocarcinoma in Mice and Decreases Inflammation

BACKGROUND & AIMSObesity is a risk factor for pancreatic ductal adenocarcinoma (PDAC), a deadly disease with limited preventive strategies. Lifestyle interventions to decrease obesity might prevent obesity-associated PDAC. Here, we examined whether decreasing obesity by increased physical activity (PA) and/or dietary changes would decrease inflammation in humans and prevent PDAC in mice. METHODSCirculating inflammatory-associated cytokines of overweight and obese subjects before and after a PA intervention were compared. PDAC pre-clinical models were exposed to PA and/or dietary interventions after obesity-associated cancer initiation. Body composition, tumor progression, growth, fibrosis, inflammation, and transcriptomic changes in the adipose tissue were evaluated. RESULTSPA decreased the levels of systemic inflammatory cytokines in overweight and obese subjects. PDAC mice on a diet-induced obesity (DIO) and PA intervention, had delayed weight gain, decreased systemic inflammation, lower grade pancreatic intraepithelial neoplasia lesions, reduced PDAC incidence, and increased anti-inflammatory signals in the adipose tissue compared to controls. PA had additional cancer prevention benefits when combined with a non-obesogenic diet after DIO. However, weight loss through PA alone or combined with a dietary intervention did not prevent tumor growth in an orthotopic PDAC model. Adipose-specific targeting of interleukin (IL)-15, an anti-inflammatory cytokine induced by PA in the adipose tissue, slowed PDAC growth. CONCLUSIONSPA alone or combined with diet-induced weight loss delayed the progression of PDAC and reduced systemic and adipose inflammatory signals. Therefore, obesity management via dietary interventions and/or PA, or modulating weight loss related pathways could prevent obesity-associated PDAC in high-risk obese individuals. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=69 SRC="FIGDIR/small/521203v1_ufig1.gif" ALT="Figure 1"> View larger version (28K): org.highwire.dtl.DTLVardef@961f1org.highwire.dtl.DTLVardef@1fd4da7org.highwire.dtl.DTLVardef@f5247aorg.highwire.dtl.DTLVardef@2de0bf_HPS_FORMAT_FIGEXP M_FIG C_FIG

cancer biology↗

Iron and lipocalin-2 modulate cellular responses in the tumor micro-environment of pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic disease with poor outcomes. Iron is known to signal cellular responses, and its levels are regulated by lipocalin-2 (LCN2) expression, a PDAC pro-tumorigenic molecule. However, how iron and LCN2 function in PDAC is unclear. Here we demonstrate that iron levels regulate PDAC cell proliferation, invasion, expression of epithelial to mesenchymal tumor markers, and pro-inflammatory cytokines. Iron chelation increased the expression of the LCN2 receptor SLC22A17 in pancreatic stellate cells and the anti-metastatic gene NDRG1 in PDAC cells. Deletion of Lcn2 in mouse tumor cells modulated the expression of genes involved in extracellular matrix deposition and cell migration. Moreover, cellular iron responses were dependent on the Kras mutation status of cells, and LCN2 expression levels. Deletion of Lcn2 expression in PDAC suggests a protective role against metastasis. Thus, iron modulation and LCN2 blockade could serve as potential therapeutic approaches against PDAC.

cancer biology↗