Disease Progression In Preclinical Models Research Articles

Abstract PS17-06: A phase I trial of the PI3K inhibitor (PI3Ki) copanlisib and fulvestrant in combination with continuous or intermittent abemaciclib in patients with estrogen receptor-positive (ER+), HER2-negative (HER2-) metastatic breast cancer

Abstract Background: Activation of the phosphoinositide 3-kinase (PI3K) pathway is a prominent resistance mechanism to endocrine therapy and CDK4/6 inhibition (CDK4/6i) in ER+, HER2- breast cancer. There is reciprocal crosstalk between PI3K and cell cycle regulatory pathways. Triplet therapy that targets ER, CDK4/6, and PI3K prevents or delays disease progression in preclinical models of ER+, HER2- breast cancer. However, the toxicities of triplet therapy hinder its clinical development. Copanlisib (COP) is an intravenous (IV) PI3Ki with potent activity against α and δ isoforms. Intermittent high-dose PI3Ki is expected to be less toxic and more effective than continuous daily dosing. We set out to determine the recommended phase 2 dose (RP2D) for the COP/Fulvestrant (FUL)/Abemaciclib (ABE) combination. Methods: Eligible patients (pts) included men or women with ER+, HER2- metastatic breast cancer (MBC), with no more than 1 prior chemotherapy in the metastatic setting, and no limits on prior endocrine or targeted therapy. Prior FUL, CDK4/6i and PI3K/mTORi were allowed. Pts with HbA1c >8.5% were excluded. Pts received FUL 500 mg IM standard dosing and COP/ABE at assigned doses. Premenopausal women also received a GnRH agonist. Dose-limiting toxicity (DLT) was assessed during the first 28-day cycle. Adverse events (AEs) were graded according to NCI-CTCAE v5.0. Dose escalation/de-escalation was based on continual reassessment (CRM) and the RP2D was defined as the dose with the highest probability of the DLT rate within the acceptable 25~35%. Results: Between June 2020 and June 2023, 24 pts with ER+, HER2- MBC were enrolled. Table 1 shows the dose levels (DLs) and DLTs. The first 10 pts were enrolled to Part A on two consecutive DLs of COP (DL1: 45 mg IV D1 and D15, n=7; DL2: 45 mg IV D1, D8, and D15, n=3), with ABE fixed at 100 mg PO BID continuously. DL2a exceeded the maximum tolerated dose (MTD). DL1a was tolerable based on Cycle 1 AEs. However, during subsequent cycles, only 1 of the 7 pts in DL1a maintained the intended dose of ABE due to neutropenia, others reduced ABE to 50mg bid (n=5) or discontinued (n=1). This triggered a protocol amendment, adding Part B with ABE administered 5 days on and 2 days off (5-on/2-off) intermittent schedule. 14 pts were enrolled to Part B in 2 consecutive DLs of COP (DL1b: n=7; DL2b: n=7), the same as in Part A. ABE was fixed at 100 mg PO Bid 5-on/2-off. DL2b exceeded the MTD. DL1b was tolerable based on Cycle 1 AEs. In addition, in subsequent cycles, only 1 of 7 pts on DL1b required dose reduction of ABE to 50mg bid. RP2D is therefore defined as DL1b. Grade (G) 4 AEs were rare. The most common all cycle G3 AEs included transient hypertension (45%), rash (30%), anemia (25%), neutropenia (25%), and AST elevation (20%). As of 6/14/2023, 22 pts, with a median of 1 prior metastatic regimen (range 0-5), prior CDK4/6i in 18 (82%), liver mets in 8 (36%), and PIK3CA mutation in 8 (50%) of 16 pts with known mutation status, were evaluable for response. There were 5 partial responses and 3 stable diseases lasting for ≥24 weeks. Clinical benefit rate was 36.4% (8/22, 95%CI: 17.19% ~ 59.34%). Responses were observed in pts regardless of prior CDK4/6i, FUL, or PIK3CA mutation. Conclusion: COP/FUL/intermittent ABE can be safely administered with fair overall tolerability. Preliminary anti-tumor activity was observed, which will be further examined in the randomized phase II trial (NCT 03939897). Table 1 Dose-limiting Toxicities by Dose Level Citation Format: Cynthia Ma, Jingqin Luo, Jessica Moss, Maryann Kwa, Ritesh Parajuli, Katia Khoury, Emily Douglas, Ashley Frith, Caron Rigden, Foluso Ademuyiwa, Shana Thomas, Brittney Haas, Gerburg Wulf, Claire Dees, Rabih Said. A phase I trial of the PI3K inhibitor (PI3Ki) copanlisib and fulvestrant in combination with continuous or intermittent abemaciclib in patients with estrogen receptor-positive (ER+), HER2-negative (HER2-) metastatic breast cancer [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PS17-06.

αGal9Ab Treatment As a Novel Therapy for Blood Cancer

Blood cancers are the most common cancer in children accounting for roughly 28% of all childhood cancers. Of these, acute lymphoblastic leukemia ( ALL) and acute myeloid leukemia ( AML) are the most prevalent. Advancements in treatment regiments for these diseases have led to a 5-year overall survival rate of 90% for pediatric ALL and 65~70% for pediatric AML; however, in patients with relapsed or refractory disease, the overall survival rates decline to 30~50% post-treatment. We have recently demonstrated that antibody-mediated targeting of Galectin-9 ( GAL-9), is highly cytotoxic to human B-ALL cells in vitro and confers a significant degree of protection for disease progression in pre-clinical models of B-ALL (M. Lee et al., Nature Communications, 2022). In unpublished studies, we have subsequently found that anti-GAL-9 antibody ( αGAL-9Ab) treatment is highly cytotoxic to human T-ALL and AML cells. Notably, we have found that human pediatric cell lines are more sensitive to this treatment than those derived from adult patients. Mechanistically, we have uncovered a previously unreported link between GAL-9-mediated regulation of checkpoint kinase 1 ( CHEK1) and anti-apoptotic protein myeloid leukemia 1 ( MCL-1), with αGAL-9Ab treatment leading to a deregulation of both proteins in T-ALL cells. Notably, αGAL-9Ab treatment synergized with multiple CHEK1 inhibitorscurrently being tested in phase I or II clinical trials (GDC-0575, Prexasertib and PF477736) to enhance the in vitro killing of human T-ALL, B-ALL, and AML cells. Furthermore, using xenograft models, we found that single-agent αGAL-9Ab treatment was superior to single-agent chemotherapy and vehicle treatment at conferring protection against T-ALL progression. In conclusion, single-agent αGAL-9Ab treatment appears to be cytotoxic against multiple acute leukemia subtypes ( ALs) and its efficacy is enhanced with CHEK1 inhibition. To validate this novel combinatorial approach for treating ALs, additional studies need to be performed to define the mechanisms of action and further pre-clinical experiments will be invaluable in determining the efficacy and safety of these therapies.

A novel direct adenosine monophosphate kinase activator ameliorates disease progression in preclinical models of Autosomal Dominant Polycystic Kidney Disease

Autosomal dominant polycystic kidney disease (ADPKD) mainly results from mutations in the PKD1 gene which encodes polycystin 1. It is the most common inherited kidney disease and is characterized by a progressive bilateral increase in cyst number and size, often leading to kidney failure. The cellular energy sensor and regulator, adenosine monophosphate stimulated protein kinase (AMPK), has been implicated as a promising new therapeutic target. To address this hypothesis, we determined the effects of a potent and selective clinical stage direct allosteric AMPK activator, PXL770, in canine and patient-derived 3D cyst models and an orthologous mouse model of ADPKD. PXL770 induced AMPK activation and dose-dependently reduced cyst growth in principal-like Madin-Darby Canine Kidney cells stimulated with forskolin and kidney epithelial cells derived from patients with ADPKD stimulated with desmopressin. In an inducible, kidney epithelium-specific Pkd1 knockout mouse model, PXL770 produced kidney AMPK pathway engagement, prevented the onset of kidney failure (reducing blood urea by 47%), decreased cystic index by 26% and lowered the kidney weight to body weight ratio by 35% compared to untreated control Pkd1 knockout mice. These effects were accompanied by a reduction of markers of cell proliferation (-48%), macrophage infiltration (-53%) and tissue fibrosis (-37%). Thus, our results show the potential of direct allosteric AMPK activation in the treatment of ADPKD and support the further development of PXL770 for this indication.

Integrative transcriptomic profiling of a mouse model of hypertension-accelerated diabetic kidney disease.

ABSTRACTThe current understanding of molecular mechanisms driving diabetic kidney disease (DKD) is limited, partly due to the complex structure of the kidney. To identify genes and signalling pathways involved in the progression of DKD, we compared kidney cortical versus glomerular transcriptome profiles in uninephrectomized (UNx) db/db mouse models of early-stage (UNx only) and advanced [UNxplus adeno-associated virus-mediated renin-1 overexpression (UNx-Renin)] DKD using RNAseq. Compared to normoglycemic db/m mice, db/db UNx and db/db UNx-Renin mice showed marked changes in their kidney cortical and glomerular gene expression profiles. UNx-Renin mice displayed more marked perturbations in gene components associated with the activation of the immune system and enhanced extracellular matrix remodelling, supporting histological hallmarks of progressive DKD in this model. Single-nucleus RNAseq enabled the linking of transcriptome profiles to specific kidney cell types. In conclusion, integration of RNAseq at the cortical, glomerular and single-nucleus level provides an enhanced resolution of molecular signalling pathways associated with disease progression in preclinical models of DKD, and may thus be advantageous for identifying novel therapeutic targets in DKD.

2-Hydroxypropyl-β-cyclodextrin is the active component in a triple combination formulation for treatment of Niemann-Pick C1 disease

Niemann-Pick type C1 (NPC1) disease is a fatal neurovisceral disease for which there are no FDA approved treatments, though cyclodextrin (HPβCD) slows disease progression in preclinical models and in an early phase clinical trial. Our goal was to evaluate the mechanism of action of a previously described combination-therapy, Triple Combination Formulation (TCF) – comprised of the histone deacetylase inhibitor (HDACi) vorinostat/HPβCD/PEG – shown to prolong survival in Npc1 mice. In these studies, TCF's benefit was attributed to enhanced vorinostat pharmacokinetics (PK). Here, we show that TCF reduced lipid storage, extended lifespan, and preserved neurological function in Npc1 mice. Unexpectedly, substitution of an inactive analog for vorinostat in TCF revealed similar efficacy. We demonstrate that the efficacy of TCF was attributable to enhanced HPβCD PK and independent of NPC1 protein expression. We conclude that although HDACi effectively reduce cholesterol storage in NPC1-deficient cells, HDACi are ineffective in vivo in Npc1 mice.

Response to: ‘Potential roles for tenascin in (very) early diagnosis and treatment of rheumatoid arthritis’ by Cutolo et al

We thank the authors for their commentary1 on our article which was recently published in the Annals of Rheumatic Diseases .2 Cutolo et al write an extended discussion of the...

Sensitivity and specificity of phospho-Ser129 α-synuclein monoclonal antibodies.

α-Synuclein (α-syn) is an abundant presynaptic protein that is the primary constituent of inclusions that define Lewy body diseases (LBDs). In these inclusions, α-syn is phosphorylated at the serine-129 residue. Antibodies directed to this phosphorylation site are used to measure inclusion abundance and stage disease progression in preclinical models as well as in postmortem tissues in LBDs. While it is critical to reliably identify inclusions, phospho-specific antibodies often cross-react with nonspecific antigens. Four commercially available monoclonal antibodies, two from rabbits (clones EP1536Y and MJF-R13) and two from mice (81a and pSyn#64), have been the most widely used in detecting pS129-α-syn inclusions. Here, we systematically evaluated these antibodies in brain sections and protein lysates from rats and mice. All antibodies detected pS129-α-syn inclusions in the brain that were induced by preformed α-syn fibrils in wild-type rats and mice. Antibody titrations revealed that clones EP1536Y and 81a comparably labeled inclusions in both the perikarya and neuronal processes in contrast to clones MJF-R13 and pSyn#64 that incompletely labeled inclusions at various antibody concentrations. Except for EP1536Y, the clones produced nonspecific diffuse neuropil labeling in α-syn knockout mice as well as mice and rats injected with monomeric α-syn, with some nonspecific staining titrating with pS129-α-syn inclusions. By immunoblot, all the clones cross-reacted with proteins other than α-syn, warranting caution in interpretations of specificity. Clone EP1536Y uniquely and robustly detected endogenous pS129-α-syn in highly soluble protein fractions from the mouse brain. In summary, EP1536Y had the highest sensitivity and specificity for detecting pS129-α-syn.

Epicutaneous Tolerance Induction to a Bystander Antigen Abrogates Colitis and Ileitis in Mice.

Although inflammatory bowel disease (IBD) is a failure in maintaining tolerance to the intestinal microbiota, few studies have investigated the use of immunologic tolerance as a treatment approach for IBD. We hypothesized that induction of immune tolerance at a distal site could suppress intestinal inflammation through a process of bystander regulation. Epicutaneous tolerance was induced by topical application of ovalbumin (OVA) using a Viaskin patch for 48 hours. In some experiments, a single feed of ovalbumin was used to drive epicutaneous tolerance-induced regulatory T cells (Tregs) to the intestine. The mechanism of tolerance induction was tested using neutralizing antibodies against TGF-β, IL-10, and Treg depletion using Foxp3-DTR mice. The capacity of skin-draining Tregs, or epicutaneous tolerance, to prevent or treat experimental IBD was tested using T-cell transfer colitis, dextran sodium sulfate (DSS) colitis, and ileitis in SAMP-YITFc mice. Weight loss, colonic inflammatory cytokines and histology were assessed. Epicutaneous exposure to ovalbumin induced systemic immune tolerance by a TGF-β-dependent, but IL-10 and iFoxp3 Treg-independent mechanism. Skin draining Tregs suppressed the development of colitis. Epicutaneous tolerance to a model antigen prevented intestinal inflammation in the dextran sodium sulfate and SAMP-YITFc models and importantly could halt disease in mice already experiencing weight loss in the T-cell transfer model of colitis. This was accompanied by a significant accumulation of LAP and Foxp3 Tregs in the colon. This is the first demonstration that epicutaneous tolerance to a model antigen can lead to bystander suppression of inflammation and prevention of disease progression in preclinical models of IBD.

Defective glycolysis and the use of 2-deoxy-D-glucose in polycystic kidney disease: from animal models to humans.

Autosomal dominant polycystic kidney disease (ADPKD) is an inherited renal disease characterized by bilateral renal cyst formation. ADPKD is one of the most common rare disorders, accounting for ~10% of all patients with end-stage renal disease (ESRD). ADPKD is a chronic disorder in which the gradual expansion of cysts that form in a minority of nephrons eventually causes loss of renal function due to the compression and degeneration of the surrounding normal parenchyma. Numerous deranged pathways have been identified in the cyst-lining epithelia, prompting the design of potential therapies. Several of these potential treatments have proved effective in slowing down disease progression in pre-clinical animal studies, while only one has subsequently been proven to effectively slow down disease progression in patients, and it has recently been approved for therapy in Europe, Canada and Japan. Among the affected cellular functions and pathways, recent investigations have described metabolic derangement in ADPKD as a major trait offering additional opportunities for targeted therapies. In particular, increased aerobic glycolysis (the Warburg effect) has been described as a prominent feature of ADPKD kidneys and its inhibition using the glucose analogue 2-deoxy-D-glucose (2DG) proved effective in slowing down disease progression in preclinical models of the disease. At the same time, previous clinical experiences have been reported with 2DG, showing that this compound is well tolerated in humans with minimal and reversible side effects. In this work, we review the literature and speculate that 2DG could be a good candidate for a clinical trial in humans affected by ADPKD.

Non Selective Inhibition of COX Activity Reversed Inflammation and Reactive Oxygen Radicals Mediated Prostate Cancer Risk and Decreased Disease Progression in Preclinical Model

Prostate cancer (PCa) represents the most frequent urologic diagnosis in elderly males. We have previously shown that exposure of prostate to lipopolysaccharide (LPS) promotes cancer risk. We investigated the effect of non-selective cyclooxygenase (COX) inhibition on prostate inflammation-mediated cancer risk in vivo. The prostates of male rats were inoculated with E. coli as sources of inflammatory molecules (LPS) and were treated with COX inhibitor, aspirin 2 mg/Kg orally for 14 days or PBS. Oxidative stress was induced with two 2 mls of hydrogen peroxide orally twice daily or PBS for 14 days; they were either treated with COX inhibitor or PBS for another 14 days. Blood was collected and analyzed for acid phosphatase and PSA. Data showed presences of LPS in the prostate of the rats resulted in gradual increase in PSA when compared to control (P P 2O2 had 2.5 fold increase in acid phosphatase (ACP) compared control (P P ity in rats.

Development and reliability of a multi-modality scoring system for evaluation of disease progression in pre-clinical models of osteoarthritis: celecoxib may possess disease-modifying properties

We sought to develop a comprehensive scoring system for evaluation of pre-clinical models of osteoarthritis (OA) progression, and use this to evaluate two different classes of drugs for management of OA. Post-traumatic OA (PTOA) was surgically induced in skeletally mature rats. Rats were randomly divided in three groups receiving either glucosamine (high dose of 192 mg/kg) or celecoxib (clinical dose) or no treatment. Disease progression was monitored utilizing micro-magnetic resonance imaging (MRI), micro-computed tomography (CT) and histology. Pertinent features such as osteophytes, subchondral sclerosis, joint effusion, bone marrow lesion (BML), cysts, loose bodies and cartilage abnormalities were included in designing a sensitive multi-modality based scoring system, termed the rat arthritis knee scoring system (RAKSS). Overall, an inter-observer correlation coefficient (ICC) of greater than 0.750 was achieved for each scored feature. None of the treatments prevented cartilage loss, synovitis, joint effusion, or sclerosis. However, celecoxib significantly reduced osteophyte development compared to placebo. Although signs of inflammation such as synovitis and joint effusion were readily identified at 4 weeks post-operation, we did not detect any BML. We report the development of a sensitive and reliable multi-modality scoring system, the RAKSS, for evaluation of OA severity in pre-clinical animal models. Using this scoring system, we found that celecoxib prevented enlargement of osteophytes in this animal model of PTOA, and thus it may be useful in preventing OA progression. However, it did not show any chondroprotective effect using the recommended dose. In contrast, high dose glucosamine had no measurable effects.

Biomarker system for studying muscle, stem cells, and cancer in vivo

Bioluminescent reporter genes are sensitive in situ tools for following disease progression in preclinical models, albeit they are subject to scattering and absorption in deep tissues. We have generated a bicistronic Cre/LoxP reporter mouse line that pairs the expression of firefly luciferase with quantifiable expression of a human placental alkaline phosphatase that is secreted into the serum (SeAP). With the use of this dual-modality bioreporter with a novel, inducible Pax7-CreER line for tracking muscle satellite cells, we demonstrate the longitudinal kinetics of muscle stem cell turnover, accounting for a doubling of the signal from satellite cell and progeny every 3.93 wk in the transition from adolescence to early adulthood. We also show that this dual-modality bioreporter can be incorporated in preclinical cancer models, whereby SeAP activity is reflective of tumor burden. Thus, this dual bioreporter permits both spatial localization and accurate quantification of biological processes in vivo even when the tissue of interest is deep within the animal.