A pilot study of virtual Harm Reduction Talking Circles for American Indian and Alaska Native adults with alcohol use disorder.

Prior research suggests that culturally aligned, accessible and lower-barrier interventions are well-placed to align with the needs of American Indian and Alaska Native (AI/AN) people with alcohol use disorder (AUD). Taking into account community members' suggestions and the need for physical distancing during the COVID-19 pandemic, our team developed a protocol for virtual Harm Reduction Talking Circles (HaRTC) to incorporate these points. The aims of this 8-week, single-arm pilot were to initially document feasibility, acceptability, and outcomes associated with attendance at virtual HaRTC, which integrates the accessibility of virtual connection, a lower-barrier harm-reduction approach, and a culturally aligned intervention. Participants (N = 51) were AI/AN people with AUD (current or in remission) across 41 Tribal affiliations and 25 US states. After a baseline interview, participants were invited to attend 8, weekly virtual HaRTC sessions. At the baseline, midpoint and post-test assessments, we collected data on virtual HaRTC acceptability, cultural connectedness, quality of life, and alcohol outcomes. Of the 123 people approached, 63% were interested in and consented to participation. Participants attended an average of 2.1 (SD = 2.02) virtual HaRTC sessions, with 64% of participants attending at least one. On a scale from 1 to 10, participants rated the virtual HaRTC as highly acceptable (M = 9.3, SD = 1.9), effective (M = 8.4, SD = 2.9), culturally aligned (M = 9.2, SD = 1.5), helpful (M = 8.8, SD = 1.9), and conducted in a good way (M = 9.8, SD = 0.5). Although the single-arm study design precludes causal inferences, participants evinced statistically significant decreases in days of alcohol use and alcohol-related harm over the three timepoints. Additionally, both sense of spirituality, which is a factor of cultural connectedness, and health-related quality of life increased over time as a function of the number of HaRTC sessions attended. Virtual HaRTC shows initial feasibility and acceptability as a culturally aligned intervention for AI/AN people with AUD. Future randomized controlled trials will provide a test of the efficacy of this approach.

Promoter-independent regulation of vimentin expression in mammary epithelial cells by val(12)ras and TGFbeta.

The 1,029 series of mammary epithelial cell lines (D6, GP+E, r3 and r3T) are progressively more transformed: the latter two by val(12)ras. These cell lines respond to TGFbeta by undergoing early events of epithelial-mesenchymal transition (EMT), including morphological changes and redistribution of E-cadherin. Tumors formed by r3T cells in the choroid of the eye express vimentin, a late marker of EMT, possibly in response to TGFbeta. In vitro, vimentin expression is induced in all the cell lines by TGFbeta treatment, whereas cytokeratin expression is only slightly affected. Surprisingly, ras transformation results in a 10-fold suppression of vimentin expression. Neither suppression of vimentin by ras transformation nor induction by TGFbeta is mediated by the vimentin promoter in r3T cells. In transient transfection assays, several human vimentin promoter constructs are more active in the low-expressing r3T cell line than in the vimentin-expressing mesenchymal cell line NIH3T3. In the r3T cells, there is no effect of TGFbeta treatment for 9 days on the activity of either promoter. Azacytidine treatment does not affect vimentin expression in either NIH3T3 or r3T, suggesting that promoter methylation is not the mechanism of suppression by ras. Finally, the half-life of the vimentin mRNA is similar in both the r3T cells and NIH3T3 cells. We conclude that the suppression of vimentin expression by ras, and the relief of this suppression by TGFbeta, occurs in a promoter-independent fashion, possibly through sequences in the first or second intron.

Inhibition of growth and metastasis of mouse mammary carcinoma by selective inhibitor of transforming growth factor-beta type I receptor kinase in vivo.

PURPOSE: Transforming growth factor-beta (TGF-beta) suppresses tumor development by inhibiting cellular proliferation, inducing differentiation and apoptosis, and maintaining genomic integrity. However, once tumor cells escape from the tumor-suppressive effects of TGF-beta, they often constitutively overexpress and activate TGF-beta, which may promote tumor progression by enhancing invasion, metastasis, and angiogenesis and by suppressing antitumor immunity. The purpose of this study was to test this hypothesis using TGF-beta pathway antagonists. EXPERIMENTAL DESIGN: We examined the effects of selective TGF-beta type I receptor kinase inhibitors, SD-093 and SD-208, on two murine mammary carcinoma cell lines (R3T and 4T1) in vitro and in vivo. RESULTS: Both agents blocked TGF-beta-induced phosphorylation of the receptor-associated Smads, Smad2 and Smad3, in a dose-dependent manner, with IC50 between 20 and 80 nmol/L. TGF-beta failed to inhibit growth of these cell lines but stimulated epithelial-to-mesenchymal transdifferentiation, migration, and invasiveness into Matrigel in vitro. These effects were inhibited by SD-093, indicating that these processes are partly driven by TGF-beta. Treatment of syngeneic R3T or 4T1 tumor-bearing mice with orally given SD-208 inhibited primary tumor growth as well as the number and size of metastases. In contrast, SD-208 failed to inhibit R3T tumor growth or metastasis in athymic nude mice. Moreover, in vitro anti-4T1 cell cytotoxic T-cell responses of splenocytes from drug-treated animals were enhanced compared with cells from control animals. In addition, SD-208 treatment resulted in a decrease in tumor angiogenesis. CONCLUSION: TGF-beta type I receptor kinase inhibitors hold promise as novel therapeutic agents for metastatic breast cancer.

Selective inhibitors of type I receptor kinase block cellular transforming growth factor-beta signaling.

Transforming growth factor (TGFbeta) is a 25-kDa dimeric polypeptide that plays a key role in a variety of physiological processes and disease states. Blocking TGFbeta signaling represents a potentially powerful and conceptually novel approach to the treatment of disorders in which the signaling pathway is constitutively activated, such as cancer, chronic inflammation with fibrosis and select immune disorders. In this paper, we describe the biological properties of a novel series of quinazoline-derived inhibitors of the type I transforming growth factor receptor kinase (TbetaKIs) that bind to the ATP-binding site and keep the kinase in its inactive conformation. These compounds effectively inhibited TGFbeta-induced Smad2 phosphorylation in cultured cells in vitro with an IC(50) between 20 and 300 nM. Moreover, TbetaKIs were able to broadly block TGFbeta-induced reporter gene activation. Finally, TbetaKIs inhibited TGFbeta-mediated growth inhibition of normal murine mammary epithelial cells (NMuMG) and mink lung epithelial cells (Mv1Lu), and TGFbeta-induced epithelial-mesenchymal transdifferentiation (EMT) of NMuMG cells. Thus, these chemical TbetaKIs have the potential to be further developed as anti-cancer and -fibrosis agents. In addition, they represent valuable new tools for dissecting the biochemical mechanisms of TGFbeta signal transduction and understanding the role of TGFbeta signaling pathways in different physiological and disease processes.