AS101 is an organotellurium compound with multifaceted immunoregulatory properties that is remarkable for its lack of toxicity. We tested the therapeutic effect of AS101 in experimental autoimmune uveitis (EAU), a model for human autoimmune uveitis. Unexpectedly, treatment with AS101 elicited Treg generation in vivo in otherwise unmanipulated mice. Mice immunized for EAU with the retinal antigen IRBP and treated with AS101 developed attenuated disease, as did AS101-treated recipients of retina-specific T cells activated in vitro. In both settings, eyeinfiltrating effector T cells were decreased, whereas regulatory T (Treg) cells in the spleen were increased. Mechanistic studies in vitro revealed that AS101 restricted polarization of retinaspecific T cells towards Th1 or Th17 lineage by repressing activation of their respective lineagespecific transcription factors and downstream signals. Retina-specific T cells polarized in vitro towards Th1 or Th17 in the presence of AS101 had impaired ability to induce EAU in naïve recipients. Finally, AS101 promoted differentiation of retina-specific T cells to Tregs in vitro independently of TGF-β. We conclude that AS101 modulates autoimmune T cells by inhibiting acquisition and expression of effector function and by promoting Treg generation, and suggest that AS101 could be useful as a therapeutic approach for autoimmune uveitis.

Diabetic nephropathy (DN) is characterized by proliferation of mesangial cells, mesangial expansion, hypertrophy and extracellular matrix accumulation. Previous data have cross-linked PKB (AKT) to TGFβ induced matrix modulation. The non-toxic compound AS101 has been previously shown to favorably affect renal pathology in various animal models and inhibits AKT activity in leukemic cells. Here, we studied the pharmacological properties of AS101 against the progression of rat DN and high glucose-induced mesangial dysfunction. In-vivo administration of AS101 to Streptozotocin injected rats didn’t decreased blood glucose levels but ameliorated kidney hypotrophy, proteinuria and albuminuria and downregulated cortical kidney phosphorylation of AKT, GSK3β and SMAD3. AS101 treatment of primary rat glomerular mesangial cells treated with high glucose significantly reduced their elevated proliferative ability, as assessed by XTT assay and cell cycle analysis. This reduction was associated with decreased levels of p-AKT, increased levels of PTEN and decreased p-GSK3β and p-FoxO3a expression. Pharmacological inhibition of PI3K, mTORC1 and SMAD3 decreased HG-induced collagen accumulation, while inhibition of GSK3β did not affect its elevated levels. AS101 also prevented HG-induced cell growth correlated to mTOR and (rp)S6 de-phosphorylation. Thus, pharmacological inhibition of the AKT downstream pathway by AS101 has clinical potential in alleviating the progression of diabetic nephropathy.

Background: Several multigene assays are available for managing ER-positive, HER2-negative early stage breast cancer but with little direct comparative information within this patient population. Existing evidence suggests that current multigene assays provide broadly equivalent risk information for the population of women with ER-positive, HER2-negative breast cancers. However, for the individual patient tests may provide differing risk categorization (Bartlett et al, JNCI 2016). We have previously demonstrated the prognostic value of different commercially available tests including Prosigna (ROR) and Oncotype Dx (RS) (Dowsett et al, JCO 2013; Sestak et al, JAMA Onc 2018). Here, we investigate risk classification and 10-year DR rates in patients that had discordant risk categorization between ROR and RS. Methods: A total of 663 postmenopausal women with ER-positive, HER2-negative, node-negative early stage breast cancer from the TransATAC study for whom both signatures were available were included in this analysis. The primary endpoint was distant recurrence (DR). Predefined ROR cut-off points for low/intermediate and intermediate/high of 40/60 were used. Comparisons were made using two sets of RS cut-off points 1) TailoRX cut-off points of 10/25 and 2) original cut-off points of 18/31. Kaplan-Meier curves were used to estimate the mean risk of DR after 10 years of follow-up in predefined risk groups. Results: Using original RS cut-off points, 25 patients (3.8%) had a high-low discordance compared to ROR, with a total of 295 (44.5%) discordant cases. Using the TailoRx cut-off points, 40 patients (6.0%) had a high-low discordance compared to ROR, with a total of 396 (59.7%) discordant cases. Applying original RS cut-off points, patients categorized into ROR low but into intermediate or high by RS (86/365 (23.6%)) had a 10-year DR rate of only 6.3% (2.7-14.6) (Table). In contrast, patients categorized into RS low but into intermediate or high by ROR (144/423 (48.6%)) had a 10-year DR rate of 13.4% (8.3-21.2). Using the TailoRx cut-off points, patients categorized into ROR low but into intermediate or high by RS (261/365 (71.5%)) had a 10-year DR rate of 2.9% (1.4-5.9), while patients with an RS low but intermediate or high by ROR (62/166 (37.3%)) had a 10-year DR rate of 18.2% (10.2-31.2) (Table). Conclusion: Discordance in risk categorization at the individual patient-level between commercially available multigene assays for early stage breast cancer is not uncommon. Our results show that node-negative patients that were classified by ROR as low risk, regardless of RS risk stratification, had an excellent 10-year DR risk with endocrine therapy alone. In contrast, patients that were classified as RS low risk by either cut-off points but were classified as intermediate or high risk by ROR had a significantly worse 10-year outcome. Our results indicate that ROR better categorized women with node negative disease into respective risk groups. Risk stratification and 10-year DR risk (%) according to ROR and RS cut-off points.ROR cut-offsLow (N=365)Intermediate/High(N=298)Original RS cut-offsNumber10-year risk (%)Number10-year risk (%)Low (N=423)2791.5%14413.4%Intermediate/High (N=240)866.3%15424.8%TailoRx cut-offsLow (N=166)1042.1%6218.2%Intermediate/High (N=497)2612.9%23619.5% Citation Format: Ivana Sestak, Sean Ferree, Itay Shemesh, Wesley Buckingham, Jack Cuzick, Mitchell Dowsett. Discordant classification and outcomes between Prosigna and Oncotype Dx Recurrence Score for ER-positive, HER2-negative, node-negative breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr P5-06-05.

e12109 Background: Trastuzumab targets HER2 directly as well as contributes to activation of the immune system against the tumor. We investigated the utility of BC molecular signatures and ISP as predictors of pCR to NAC+T in HER2+ BC pts. Methods: The analysis included 73 consecutive HER2+ BC pts with pathological samples at diagnosis, who received NAC+T. RNA was extracted from 73/22 biopsy/surgical specimens (FFPE). RNA was analyzed using NanoString PanCancer Immunoncology 360 (IO360) panel with PAM50 spike-in. Raw gene counts were log2-transformed and normalized (using housekeeping genes). The analysis assessed 47 gene signatures including immune related and PAM50 signatures. Signatures were computed after removing samples with low expression of the housekeeping genes and normalization. Signature scores range from ~0 to 10 and have an average value of 5 in tumor samples from The Cancer Genome Atlas. Results: Overall, 46% of the pts achieved pCR; of 13 pts who were IHC 2+ and FISH positive, one achieved pCR. Significant associations were found between response to NAC+T (pCR, no response) and molecular signatures/ISP from the initial biopsy (Table). For pts who did not experience pCR and who underwent surgery, paired sample analysis was performed assessing molecular signatures/ISP in the initial biopsy sample vs the surgical sample. This analysis demonstrated a significant increase post-treatment (compared to the initial biopsy sample) in Risk of Recurrence (ROR) score (p=.036), interferon (IFN) downstream signature (p=.038), and antigen‐processing machinery (APM) loss (p=.002). Conclusions: Combining molecular BC signatures and ISP on biopsy samples may have a predictive value in HER2+BC pts for whom NAC+T is considered. Luminal A pts and IHC 2+ (FISH positive) are unlikely to achieve pCR with NAC+T. [Table: see text]

AS101 is an organotellurium compound with multifaceted immunoregulatory properties that is remarkable for its lack of toxicity. We tested the therapeutic effect of AS101 in experimental autoimmune uveitis (EAU), a model for human autoimmune uveitis. Unexpectedly, treatment with AS101 elicited Treg generation in vivo in otherwise unmanipulated mice. Mice immunized for EAU with the retinal antigen IRBP and treated with AS101 developed attenuated disease, as did recipients of retina-specific T cells activated in vitro in the presence of AS101. In both settings, eye-infiltrating effector T cells were decreased, whereas regulatory T (Treg) cells in the spleen were increased. Mechanistic studies in vitro revealed that AS101 restricted polarization of retina-specific T cells towards Th1 or Th17 lineage by repressing activation of their respective lineage-specific transcription factors and downstream signals. Retina-specific T cells polarized in vitro towards Th1 or Th17 in the presence of AS101 had impaired ability to induce EAU in naïve recipients. Finally, AS101 promoted differentiation of retina-specific T cells to Tregs in vitro independently of TGF-β. We conclude that AS101 modulates autoimmune T cells by inhibiting acquisition and expression of effector function and by promoting Treg generation, and suggest that AS101 could be useful as a therapeutic approach for autoimmune uveitis.