Fariba Moeinpour

MECHANISM OF THE ANTI-INFLAMMATORY EFFECT OF 17β-ESTRADIOL ON BRAIN FOLLOWING TRAUMA-HEMORRHAGE

ABSTRACT Although 17&bgr;-estradiol (E2) is reported to improve the inflammatory response after trauma-hemorrhage (T-H), it remains unknown whether E2 plays any role in the central nervous system after T-H. Microglial cells, resident central macrophages, are thought to play a central role in exacerbating cell-mediated inflammation. We hypothesized that T-H up-regulates microglial cell-mediated inflammatory response in the brain, and E2 produces central anti-inflammatory effects via negative regulation of microglial cells. Male Sprague-Dawley rats were subjected to sham operation (cannulation plus laparotomy) or T-H (midline laparotomy; mean blood pressure, 35 ± 5 mmHg for 90 min followed by resuscitation) and immediately killed after resuscitation. Rats received vehicle or E2 (1 mg/kg body weight i.v.) at the onset of resuscitation. In other experiments, minocycline (40 mg/kg body weight i.p.), microglia inhibitor, was administered 1 h before T-H to prevent inflammatory response in the microglia after T-H. The plasma and hypothalamic tumor necrosis factor (TNF-&agr;) levels were increased, along with the activation of microglial cells in T-H rats compared with shams. Furthermore, T-H increased microglial TNF-&agr; productive capacity in vitro. 17&bgr; administration after T-H prevented these inflammatory responses. In rats pretreated with minocycline, decreased microglial TNF-&agr; production and hypothalamic TNF-&agr; levels were observed, but plasma TNF-&agr; levels were not altered after T-H. Thus, T-H induces inflammatory responses even in the hypothalamus, and E2 seems to be a useful adjunct for down-regulating microglial cell-mediated inflammatory response after T-H.

Lack of effect of metformin on mammary carcinogenesis in nondiabetic rat and mouse models.

Epidemiologic studies have shown that diabetics receiving the biguanide metformin, as compared with sulfonylureas or insulin, have a lower incidence of breast cancer. Metformin increases levels of activated AMPK (AMP-activated protein kinase) and decreases circulating IGF-1; encouraging its potential use in both cancer prevention and therapeutic settings. In anticipation of clinical trials in nondiabetic women, the efficacy of metformin in nondiabetic rat and mouse mammary cancer models was evaluated. Metformin was administered by gavage or in the diet, at a human equivalent dose, in standard mammary cancer models: (i) methylnitrosourea (MNU)-induced estrogen receptor–positive (ER+) mammary cancers in rats, and (ii) MMTV-Neu/p53KO ER− (estrogen receptor–negative) mammary cancers in mice. In the MNU rat model, metformin dosing (150 or 50 mg/kg BW/d, by gavage) was ineffective in decreasing mammary cancer multiplicity, latency, or weight. Pharmacokinetic studies of metformin (150 mg/kg BW/d, by gavage) yielded plasma levels (Cmax and AUC) higher than humans taking 1.5 g/d. In rats bearing small palpable mammary cancers, short-term metformin (150 mg/kg BW/d) treatment increased levels of phospho-AMPK and phospho-p53 (Ser20), but failed to reduce Ki67 labeling or expression of proliferation-related genes. In the mouse model, dietary metformin (1,500 mg/kg diet) did not alter final cancer incidence, multiplicity, or weight. Metformin did not prevent mammary carcinogenesis in two mammary cancer models, raising questions about metformin efficacy in breast cancer in nondiabetic populations. Cancer Prev Res; 8(3); 231–9. ©2015 AACR.

Quantitative analysis of growth factors from a second filter using the Reamer-Irrigator-Aspirator system: description of a novel technique.

Use of the Reamer-Irrigator-Aspirator (RIA) as a source of autogenous bone graft in the treatment of nonunions is increasing. We report on our novel technique of using a second filter containing beta-tricalcium phosphate (TCP) as a graft extender while using the RIA system. We also quantify growth factor concentrations in the collections from the TCP filter. A second filter attached in series with the standard RIA filtration system yields TCP with substantial concentrations of bioactive proteins that are equal to those seen in the bone graft that is harvested in the first filter.

Lack of chemopreventive efficacy of metformin in rodent models of urinary bladder, head and neck, and colon/intestine cancer

Metformin is a biguanide employed in treating type II diabetes. Its potential efficacy for treating cancer has been demonstrated epidemiologically (lower cancer incidence in metformin users compared with users of sulfonylureas or insulin) and mechanistically, primarily in cell culture. Metformin decreases the levels of insulin-like growth factor 1 and secondarily inhibits the mammalian target of rapamycin pathway to exhibit anticancer effects. The current study examined its cancer preventive efficacy in multiple standard in situ arising cancer models. Metformin was administered orally by gavage or in the diet, at human equivalent doses, in numerous cancer models. In the hydroxybutyl(butyl)nitrosamine-induced model of invasive urinary bladder cancer, metformin (50 or 150 mg/kg body weight/day, intragastric) was ineffective despite high urinary concentrations of metformin. Metformin (250 or 500 ppm in diet) failed to decrease the incidence or invasiveness of squamous cell cancer of the tongue in a 4-nitroquinoline-1-(4NQO)-induced model. Finally, in the Min mouse model of gastrointestinal cancer, metformin (400 or 1,200 ppm in diet) was ineffective. Notably, a slight increase in intestinal tumor multiplicity was observed at the higher dose. Therefore, metformin lacked efficacy in multiple standard cancer models in non-diabetic rodents. This lack of efficacy may discourage any large phase clinical cancer trials in non-diabetic individuals in the absence of clear phase-II studies.

Abstract P3-11-04: Metabolic profiles in female Sprague-Dawley rats receiving either a standard (4% fat) or Western (20% fat) diet and changes in rats bearing mammary cancers

The methylnitrosourea(MNU)-induced model of ER + mammary cancers in female Sprague-Dawley rats has been routinely used in our laboratories for screening chemopreventive agents. We recently reported that metformin was ineffective in preventing mammary cancers in this model when given to rats on a standard diet (Thompson, et al, Cancer Prev Res. 2015;8:231-9). In this study, we evaluated metformin in rats placed on either standard diet (4% fat) or a Western diet (20% fat, low calcium). As fat calories, these diets were 8% and 42%, respectively. The rats were placed on standard diet or Western diet at 43 days of age, given MNU (via the jugular vein) once at 50 days of age, and administered metformin or vehicle at 57 days of age for the remainder of the study. Serum of the rats in the various groups was obtained at 78 days of age, and at the end of the study (when mammary tumors were present). The levels of approximately 500 metabolites were compared in the serum based on data obtained by Metabolon (Research Triangle Park, NC). These studies showed that each of the four groups [(standard diet (early and late) or Western diet (early and late)] yielded four clearly distinct patterns based on an unsupervised principal component analysis. Certain of the metabolites which were differentially expressed in serum from standard vs Western diets at the early time point were alpha-10-undecanoate, 13-methylmyristic acid, 4-hydroxy-benzoate, 2-amino-heptanpate, tocopherol, and nicotinamide. Certain of these were fatty acids and lipid soluble vitamins that one would expect to be altered. Comparing serum from standard vs Western diets at the late time point confirmed many of these metabolic differences. We also compared serum from the early and late time points since the latter serums were typically from animals with a significant number of mammary cancers. We observed a number of metabolite changes including 4-hydroxy-butyrate, acetyl-carnitine, oxalate, and threonate. These cancer- related profiles will be discussed at greater lengths. Altered profiles caused by the administration of metformin and other chemopreventive agents will also be discussed. Of interest, metformin was consistently ineffective in preventing mammary cancers in rats given either standard or Western diet. Supported by NCI contract HHSN261201200021I. Citation Format: Thompson MD, Grubbs CJ, Moeinpour F, Steele VE, Miller MS, Lubet RA. Metabolic profiles in female Sprague-Dawley rats receiving either a standard (4% fat) or Western (20% fat) diet and changes in rats bearing mammary cancers. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P3-11-04.

Abstract 2626: Metabolic profiles and potential pharmacodynamic biomarkers in female Sprague-Dawley rats on a standard (4% fat) or Western (20% fat) diet and treated with known active or inactive chemopreventive agents

Proceedings: AACR 107th Annual Meeting 2016; April 16-20, 2016; New Orleans, LA The methylnitrosourea (MNU) - induced model of ER+ mammary cancers in female Sprague-Dawley rats has been routinely used in our laboratories for screening chemopreventive agents. In this study, we evaluated multiple known effective [tamoxifen, Targretin (an RXR agonist), Iressa (EGFR1 inhibitor)] or ineffective agents (Lipitor, metformin) in rats placed on either standard diet (20% fat) or a Western diet (20% fat, low calcium) at 43 days of age (DOA). Rats were given MNU at 50 DOA and administered the various agents or vehicle beginning at 57 DOA until the end of the study. Palpation of the rats showed that agents yielded the same results in rats on either diets. Somewhat surprisingly, metformin was ineffective in rats on either diet; confirming our lack of efficacy in a standard diet (Thompson, et al, Cancer Prev Res., 2015). To look for potential pharmacodynamics biomarkers, serum was obtained from the various groups at 78 days of age and at sacrifice; when a large tumor burden was observed in rats given vehicle, Lipitor, or metformin. Levels of approximately 500 metabolites were compared in the serum (Metabolon Research, Research Triangle Park, NC). We initially looked for metabolite changes related to different diets and found differential expression of alpha 10-undecanoate, 13-methylmyristic acid, 4-hydrox-benzoate, 2-amino-heptanpate, tocopherol and nicotinamide when comparing serum from rats on Western vs standard diets. Interestingly, each of the highly effective agents (tamoxifen, Targretin, and Iressa) yielded metabolic profiles that were strikingly different from rats given vehicle; based on unsupervised analysis. These metabolites become potential pharmacodynamic biomarkers for the highly effective doses of these agents. In contrast, the two negative agents did not yield a similar dichotomy between treated and vehicle serum. One could determine, however, metabolites which differed between metformin or Lipitor treated rats vs vehicle treated rats when performing a supervised analysis. We also compared serum for the early and late time points with either diet since the latter serum was from animals with a significant number of mammary cancers. We observed a number of metabolite changes including 4-OH butyrate, acetyl carnitine, oxalate, and threonate. These cancer related profiles will be discussed at greater length; in addition to the altered profiles caused by the administration of the various chemopreventive agents. Supported by NCI contract HHSN261201200021I. Citation Format: Matthew D. Thompson, Clinton J. Grubbs, Vernon E. Steele, Mark S. Miller, Fariba Moeinpour, Edward D. Karoly, Ronald A. Lubet. Metabolic profiles and potential pharmacodynamic biomarkers in female Sprague-Dawley rats on a standard (4% fat) or Western (20% fat) diet and treated with known active or inactive chemopreventive agents. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 2626.

Abstract 4657: Targeting STAT3 for mammary cancer prevention in MMTV/Neu mice employing the antagonist GLG-302

Proceedings: AACR 106th Annual Meeting 2015; April 18-22, 2015; Philadelphia, PA GLG-302 (S3I-201, NSC 74859) from the National Cancer nstitute chemical libraries was identified as a STAT3 antagonist using structure-based virtual screening with a computer model of the Stat3 SH2 domain bound to its Stat3 phosphotyrosine peptide derived from the x-ray crystal structure of the Stat3 homodimer. In addition to preclinical therapeutic efficacy in breast, glioma, and pancreatic cancer, it ameliorated the resistance to cetuximab and doxorubicin in models of liver cancer. It was well tolerated in mice, rats and dogs in pilot safety studies. Since our laboratories have shown that activated STAT3 is present in normal mammary tissue of young mice and mammary cancers, we evaluated the efficacy of GLG-302, given orally, for its preventive activity in female MMTV-Neu mice that develop spontaneous estrogen receptor negative (ER−) mammary cancers. Previous studies had shown that acute dosing with GLG-302 would suppress the growth of established mammary cancers in mouse models at tolerable doses. We conducted a dose selection study lasting 3 months indicating that doses of GLG-302 as high as 500 mg/kg BW/day (administered by gavage 5X/week) would not alter body weights or induce other signs of toxicity. Proliferation rates (Ki67) in the mammary glands of the mice, determined after 2 weeks and after 3 months of GLG-302 administration, revealed that this dose of the agent caused reductions of 66% and 55%, respectively. A cancer prevention efficacy study was then initiated that included the following groups (15 mice/group); Group 1, GLG-302 (500 mg/kg BW/day); Group 2, GLG-302 (250 mg/kg BW/day); Group 3, GLG-302 (125 mg/kg BW/day); Group 4, Lapatinib (100 mg/kg BW/day) as a positive control; and Group 5, no treatment. Treatment (5X/week) was initiated when the mice were 65 days of age, and will continue for 10 months. Mammary tumors are detected by palpation of the mice 2X/week. The study is currently 5 months after the initial GLG-302 treatment. Average palpable mammary tumor number in each group is: Group 1, 0.07; Group 2, 0.33, Group 3, 0.50, Group 4, 0.08, and Group 5, 1.20. The 94% reduction in the average number of mammary tumors observed in mice receiving the high dose of GLG-302 compared to that in the no treatment group; and is comparable to the reduction observed following treatment with lapatinib. No body weight loss or other toxicity has been observed. In conclusion, IHC data demonstrated that GLG-302 can target the normal mammary epithelial cells of the mouse mammary gland during well-tolerated chronic dosing of the agent. Furthermore, current data in the prevention study has demonstrated a dose-dependent decrease in spontaneous mammary tumors in female MMTV/Neu mice. Additional studies using GLG-302 are ongoing in the dimethylbenzanthracene-induced mammary cancer (ER+) rat model, and will be presented. Studies supported by NCI contract HHSN261201200021I. Citation Format: Robert H. Shoemaker, Michael W. Lovell, John J. Whalen, Fariba Moeinpour, Clinton J. Grubbs. Targeting STAT3 for mammary cancer prevention in MMTV/Neu mice employing the antagonist GLG-302. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4657. doi:10.1158/1538-7445.AM2015-4657

Sex hormones and gender effects following trauma-hemorrhage.

Trauma is the leading cause of death in the industrialized world between the ages of one and 40. A number of risk factors including age and gender have been implicated in this regard. It is therefore not surprising that the majority of trauma victims are young males. Their mortality rate following trauma is not only higher compared to females, but they are also more prone to subsequent sepsis. Age and gender are therefore important factors in the prevalence of traumatic injury as well as in susceptibility to subsequent septic complications.