Novel, isoform-selective, cholecystokinin A receptor antagonist inhibits colon and pancreatic cancers in preclinical models through novel mechanism of action

Colon and pancreatic cancers contribute to 90,000 deaths each year in the USA. These cancers lack targeted therapeutics due to heterogeneity of the disease and multiple causative factors. One important factor that contributes to increased colon and pancreatic cancer risk is gastrin. Gastrin mediates its actions through two G-protein coupled receptors (GPCRs): cholecystokinin receptor A (CCK-A) and CCK-B/gastrin receptor. Previous studies have indicated that colon cancer predominantly expresses CCK-A and responds to CCK-A isoform antagonists. However, many CCK-A antagonists have failed in the clinic due to poor pharmacokinetic properties or lack of efficacy. In the present study, we synthesized a library of CCK-A isoform-selective antagonists and tested them in various colon and pancreatic cancer preclinical models. The lead CCK-A isoform, selective antagonist PNB-028, bound to CCK-A at 12 nM with a 60-fold selectivity towards CCK-A over CCK-B. Furthermore, it inhibited the proliferation of CCK-A-expressing colon and pancreatic cancer cells without affecting the proliferation of non-cancerous cells. PNB-028 was also extremely effective in inhibiting the growth of MAC-16 and LoVo colon cancer and MIA PaCa pancreatic cancer xenografts in immune-compromised mice. Genomewide microarray and kinase-array studies indicate that PNB-028 inhibited oncogenic kinases and angiogenic factors to inhibit the growth of colon cancer xenografts. Safety pharmacology and toxicology studies have indicated that PNB-028 is extremely safe and has a wide safety margin. These studies suggest that targeting CCK-A selectively renders promise to treat colon and pancreatic cancers and that PNB-028 could become the next-generation treatment option

A New Generation of Selective Androgen Receptor Degraders : Our Initial Design, Synthesis, and Biological Evaluation of New Compounds with Enzalutamide-Resistant Prostate Cancer Activity

This research was supported by the Van Vleet Endowed Professorship (D.D.M.), and GTx, Inc. grant (R.N. and D.D.M.) We thank GTx, Inc. for supporting this project and Dr. Dejian Ma of UTHSC, College of Pharmacy for assistance with 2D NMR and HRMS experiments.Peer reviewedPostprin

Pharmacologic activation of estrogen receptor α increases mitochondrial function, energy expenditure, and brown adipose tissue

Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154285/1/fsb2fj201600787rr.pd

Orally Bioavailable Androgen Receptor Degrader, Potential Next-Generation Therapeutic for Enzalutamide-Resistant Prostate Cancer

Acknowledgement. BGS acknowledges work performed at the Center for Nanophase Materials Sciences, a DOE Office of Science User Facility. VB acknowledges Laboratory Directed Research and Development program of Oak Ridge National Laboratory, managed by UTBattelle, LLC, for the U.S. Department of Energy.Peer reviewedPostprin

Androgen receptor agonists increase lean mass, improve cardiopulmonary functions and extend survival in preclinical models of Duchenne muscular dystrophy

© The Author 2017. Duchenne muscular dystrophy (DMD) is a neuromuscular disease that predominantly affects boys as a result of mutation(s) in the dystrophin gene. DMD is characterized by musculoskeletal and cardiopulmonary complications, resulting in shorter life-span. Boys afflicted by DMD typically exhibit symptoms within 3-5 years of age and declining physical functions before attaining puberty. We hypothesized that rapidly deteriorating health of pre-pubertal boys with DMD could be due to diminished anabolic actions of androgens in muscle, and that intervention with an androgen receptor (AR) agonist will reverse musculoskeletal complications and extend survival. While castration of dystrophin and utrophin double mutant (mdx-dm) mice to mimic pre-pubertal nadir androgen condition resulted in premature death, maintenance of androgen levels extended the survival. Non-steroidal selective-AR modulator, GTx-026, which selectively builds muscle and bone was tested in X-linked muscular dystrophy mice (mdx). GTx-026 significantly increased body weight, lean mass and grip strength by 60-80% over vehicle-treated mdx mice. While vehicle-treated castrated mdx mice exhibited cardiopulmonary impairment and fibrosis of heart and lungs, GTx-026 returned cardiopulmonary function and intensity of fibrosis to healthy control levels. GTx-026 elicits its musculoskeletal effects through pathways that are distinct from dystrophin-regulated pathways, making AR agonists ideal candidates for combination approaches. While castration of mdx-dm mice resulted in weaker muscle and shorter survival, GTx-026 treatment increased the muscle mass, function and survival, indicating that androgens are important for extended survival. These preclinical results support the importance of androgens and the need for intervention with AR agonists to treat DMD-affected boys

Novel Selective Agents for the Degradation of Androgen Receptor Variants to Treat Castration-Resistant Prostate Cancer

Acknowledgements: The authors thank Mr. Maron Lee Barrett and Ms. Mayra Star for their technical help. The authors thank Dr. Dejian Ma for his technical help with the NMR studies. The authors thank the UTHSC and St. Jude NMR core for their help with the NMR studies. The authors thank Drs. Robert Getzenberg and Michael Mohler for providing useful comments on the manuscript. The authors thank Ms. Brandy Grimes for her help with tissue procurement. The authors thank Dr. Daniel Johnson of UT BioCore for microarray data analysis and Mr. Lorne Rose of UT-MRC core for microarray studies. Funding Source: The research presented in this manuscript was supported by a research funding provided by GTx, Inc. Memphis, TN to R. Narayanan and by a research funding provided by West Cancer Center to R. Narayanan.Peer reviewedPostprin

Reducing FLI1 levels in the MRL/lpr lupus mouse model impacts T cell function by modulating glycosphingolipid metabolism.

Systemic Lupus erythematosus (SLE) is an autoimmune disease caused, in part, by abnormalities in cells of the immune system including B and T cells. Genetically reducing globally the expression of the ETS transcription factor FLI1 by 50% in two lupus mouse models significantly improves disease measures and survival through an unknown mechanism. In this study we analyze the effects of reducing FLI1 in the MRL/lpr lupus prone model on T cell function. We demonstrate that adoptive transfer of MRL/lpr Fli1(+/+) or Fli1(+/-) T cells and B cells into Rag1-deficient mice results in significantly decreased serum immunoglobulin levels in animals receiving Fli1(+/-) lupus T cells compared to animals receiving Fli1(+/+) lupus T cells regardless of the genotype of co-transferred lupus B cells. Ex vivo analyses of MRL/lpr T cells demonstrated that Fli1(+/-) T cells produce significantly less IL-4 during early and late disease and exhibited significantly decreased TCR-specific activation during early disease compared to Fli1(+/+) T cells. Moreover, the Fli1(+/-) T cells expressed significantly less neuraminidase 1 (Neu1) message and decreased NEU activity during early disease and significantly decreased levels of glycosphingolipids during late disease compared to Fli1(+/+) T cells. FLI1 dose-dependently activated the Neu1 promoter in mouse and human T cell lines. Together, our results suggest reducing FLI1 in lupus decreases the pathogenicity of T cells by decreasing TCR-specific activation and IL-4 production in part through the modulation of glycosphingolipid metabolism. Reducing the expression of FLI1 or targeting the glycosphingolipid metabolic pathway in lupus may serve as a therapeutic approach to treating lupus

<i>Fli1</i>^<i>+/-</i> T cells have significantly lower levels of Neuraminidase 1 (<i>Neu1</i>) message and NEU activity compared to <i>Fli1</i>^<i>+/+</i> T cells during early disease.

<p>cDNA was amplified from RNA isolated from T cells of MRL/lpr <i>Fli1</i>^<i>+/+</i> and <i>Fli1</i>^<i>+/-</i> 10-12 week-old mice (A) and 17-18 week-old mice (C). <i>Neu1</i> and <i>Neu3</i> message levels were measured by real-time PCR and normalized to <i>β-actin</i> levels. B) NEU activity was measured as described in the methods. Relative levels in the NEU activity assay were calculated to combine all animals across experiments as described in the methods. The ‘n’ represents data from individual animals and p values are provided within the figure.</p

<i>Fli1</i>^<i>+/-</i> T cells have significantly lower levels of Neuraminidase 1 (<i>Neu1</i>) message and NEU activity compared to <i>Fli1</i>^<i>+/+</i> T cells during early disease.

<p>cDNA was amplified from RNA isolated from T cells of MRL/lpr <i>Fli1</i>^<i>+/+</i> and <i>Fli1</i>^<i>+/-</i> 10-12 week-old mice (A) and 17-18 week-old mice (C). <i>Neu1</i> and <i>Neu3</i> message levels were measured by real-time PCR and normalized to <i>β-actin</i> levels. B) NEU activity was measured as described in the methods. Relative levels in the NEU activity assay were calculated to combine all animals across experiments as described in the methods. The ‘n’ represents data from individual animals and p values are provided within the figure.</p

Glycosphingolipid levels are significantly reduced in T cells from late disease stage MRL/lpr <i>Fli1</i>^<i>+/-</i> compared to MRL/lpr <i>Fli1</i>^<i>+/+</i> mice.

<p>Glycosphingolipids lactosylceramide (LacCer) (A) and glucosylceramide (GluCer) (B) were measured by SFC/MS/MS in unstimulated or anti-CD3/CD28 stimulated T cells isolated from 17–18 week-old MRL/lpr mice. *p<0.05, **p<0.01, #p<0.005, # #p<0.001. The ‘n’ represents data from individual animals.</p