CK2 is a pleiotropic, heterotetrameric kinase elevated in numerous cancers and, as such, has garnered much attention as a target for novel antineoplastic agents. Currently, silmitasertib, a selective CK2 inhibitor, has an orphan designation for medulloblastoma and neuroblastoma. Tissue-specific overexpression of the catalytic subunit, CK2α, is sufficient to drive the development of mammary tumors in mice, underlying its potential role in breast oncogenesis. Our lab has demonstrated that CK2β protein expression is associated with endocrine resistance and that targeted disruption of CK2 activity results in ERα proteolysis. Among the factors driving endocrine resistance is overexpression of HER2/EGFR, which contributes to both proliferation and phenotypic plasticity in ER+ breast cancer. Here, we sought to determine the impact of CK2 targeting on HER2/EGFR signaling, phenotypic plasticity, and cell proliferation in endocrine-sensitive and endocrine-resistant breast cancer. Furthermore, we explored the potential of combined lapatinib and CK2-based therapies in decreasing breast cancer proliferation and epithelial-mesenchymal transition (EMT). CK2 subunit expression and function were investigated in ERα-mutant, tamoxifen-resistant MCF-7 Y537S breast cancer cells and additional breast cancer subtypes. CK2 was inhibited pharmacologically using CX-4945 or genetically via shRNA knockdown of CK2β. Cell proliferation, spheroid growth, migration, and EMT markers were assessed using live-cell imaging, wound-healing assays, immunoblotting, and qRT-PCR. Publicly available patient datasets were analyzed to evaluate the prognostic relevance of CSNK2B expression. CK2β expression was significantly upregulated in ERα-mutant breast cancer cells and patient tumors. Pharmacological inhibition or genetic depletion of CK2β suppressed proliferation, spheroid formation, and migration, accompanied by reduced ERK phosphorylation and cyclin D1 expression. CK2β inhibition also attenuated EMT, marked by decreased N-cadherin, vimentin, and EMT transcription factors, while enhancing E-cadherin expression. High CSNK2B expression correlated with poorer relapse-free survival, particularly in ERα+ and HER2-E breast cancers. Notably, CK2β inhibition sensitized breast cancer cells to HER2-targeted therapy. CK2 is a critical regulator of endocrine-resistant breast cancer progression, promoting proliferation, EMT, and therapeutic resistance through ERK/cyclin D1 signaling. Inhibition of CK2 potentiated the effects of lapatinib across several cell lines. Furthermore, shRNA-mediated knockdown of the CK2β subunit phenocopies pharmacological disruption of CK2 and highlights the significance of the regulatory subunit in breast cancer cell biology. Targeting CK2, and, more selectively, CK2β represent a promising approach to overcome endocrine resistance and enhance responsiveness to HER2-directed treatments.

Resistance to endocrine therapy remains a significant clinical hurdle to the management of breast cancer. Mutations in the ESR1 gene (most frequently Y537S) are associated with metastatic disease recurrence in patients previously treated with endocrine therapy. We have shown that silmitasertib, a clinical phase CK2 inhibitor, can inhibit the proliferation of tamoxifen-sensitive and tamoxifen-resistant breast cancer cells in part by disrupting ERα/ERα variant expression. As such, we investigated the antiproliferative and antimigratory efficacy of silmitasertib in CRISPR-edited MCF-7 cells expressing ERαY5237S. Our findings suggest that pharmacological targeting of CK2 may represent an effective strategy in treating ERα-mutated, endocrine therapy-resistant BCa. Using parental MCF-7 and MCF-7 ERαY537S cells, we assessed cell proliferation in the monolayer cultures, as well as 3D spheroid growth and wound healing activity using live cell imaging in the presence of silmitasertib. We measured the impact of CK2 inhibition on established mitogenic pathways by RT-PCR and/or immunoblot analysis (Her2, Cyclin D1, S6/pS6, S27, ERK/pERK). Subsequently, we assessed the efficacy of combined exposure to the HER2/EGFR inhibitor lapatinib with or without silmitasertib in both MCF-7 and MCF-7 Y537S cells. Our studies show that MCF-7 Y537S cells exhibit enhanced sensitivity to both antiproliferative and anti-migratory effects of silmitasertib compared to parental MCF-7 cells. HER2 was also overexpressed in MCF-7 Y537S, and the combination of lapatinib and silmitasertib, revealed an additive effect on cell proliferation. Our studies suggest that the development of ERαY537S mutations in BCa results in enhanced sensitivity to growth inhibition elicited by CK2 blockade. Our studies provide a convincing rationale for the therapeutic targeting of CK2 in the context of ERα-mutated, endocrine-resistant breast cancer. DeZha Robinson, Hogyoung Kim, Alexandra Caroline Dunn, Clark Jules Perkins, Sihyoung Kim, Sichan kim, Emily Lauren Schenk-Smith, Simak Ali, Matthew Burow, Emma Elkins, Christopher Williams. Targeting the Her2 and ERα receptors has a significant impact on therapy-resistant ER-positive breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6768.

Approximately 75% of breast cancer tumors express the estrogen receptor alpha steroid receptor. Canonical estrogen receptors ERα66 and ERβ1 are the main mediators of estrogen-dependent pathophysiology in mammals. However, numerous isoforms have been identified, stimulating unconventional estrogen response pathways leading to complex cellular and tissue responses. Estrogen receptor alpha plays essential roles in the human body, such as the reproductive organs and metabolic and inflammatory systems. Recent studies suggest that a 36 kD variant of ERα (ERα36, ERα isoform 4) may play a role in endocrine therapy resistance in breast carcinoma (BCa). However, a key limitation to discovering the precise role of ERα36 in BCa is the lack of reliable, commercially available antibodies. Most ERα polyclonal antibodies show poor antigen specificity, hindering the evaluation of ERα36 as a clinical biomarker in BCa. Our goal is to develop a reliable monoclonal antibody targeting ERα36, which could facilitate its development as a clinical biomarker in BCa. Here, we describe the development of hybridoma producing an ERα36 monoclonal antibody (34F11) followed by rigorous enrichment (ultrafiltration), purification (fast protein liquid chromatography), and affinity (spectral shift assay) characterization. We assessed the utility of 34F11 antibody in several applications (immunoblot, immunohistochemistry, and fluorescence cytometry). Here, we provide the first comparative characterization of a monoclonal antibody directed toward ERα36 for the potential implementation of biomarker detection in BCa. Alexandra C. Selico Dunn, Hogyoung Kim, DeZha A. Robinson, Sihyoung Kim, Clark J. Perkins, Sichan Kim, Emily L. Smith, Emma Elkins, Christopher Williams. Development of novel monoclonal antibody detection of ERα36 in breast cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 4634.

Female breast cancer accounts for 15.2% of all new cancer cases in the United States, with a continuing increase in incidence despite efforts to discover new targeted therapies. With an approximate failure rate of 85% for therapies in the early phases of clinical trials, there is a need for more translatable, new preclinical in vitro models that include cellular heterogeneity, extracellular matrix, and human-derived biomaterials. Specifically, adipose tissue and its resident cell populations have been identified as necessary attributes for current preclinical models. Adipose-derived stromal/stem cells (ASCs) and mature adipocytes are a normal part of the breast tissue composition and not only contribute to normal breast physiology but also play a significant role in breast cancer pathophysiology. Given the recognized pro-tumorigenic role of adipocytes in tumor progression, there remains a need to enhance the complexity of current models and account for the contribution of the components that exist within the adipose stromal environment to breast tumorigenesis. This review article captures the current landscape of preclinical breast cancer models with a focus on breast cancer microphysiological system (MPS) models and their counterpart patient-derived xenograft (PDX) models to capture patient diversity as they relate to adipose tissue.

The African environment has for millennia been dominated by rampant agents of infections, of which malaria is among the best known, virtually uncontrolled, and associated with lifelong human struggles, ameliorarated by measures as socioeconomicaly affordable. This has led to the emergence of a variety of genetic aberrations, some of which are deleterious, resulting in major disease dysparities, including benign ones like sickle cell disease, and malignancies like the leukaemias, lymphomas, and breast cancer. They include the reduced incidence and the absence of its peak in acute lymphoblastic leukaemia in the first quinquennium of Nigerian children, which is otherwise typically seen in the children of high-income countries. Conversely is the observation in acute myelogenous leukaemia, with its chloroma-associated variant and its incidence peaking in the second quinquennium. This epidemiology is akin to the recent observation of acute myelogenous leukemia among sickle cell disease patients among the people of African descent in California, USA. Chloroma-associated acute myelogenous leukemia, and Burkitt lymphoma are linked with low socioeconomic status, an epidemiological feature that is shared with triple negative breast cancer patients in West Africa and the women of African descent in the United States. While a role for the malaria-associated genetic aberration underlying the Duffy null genotype is confirmed in the diversity of the triple negative breast cancer in the women of West Africa and those of African descent in the United States, it is conceivable, but not yet established in acute myelogenous leukemia. The zoonosis-linked human T-cell lymphotropic virus type 1 infection is associated with at least 17% of non-BL-non-Hodgkin lymphoma in form of its sentinel disease, the adult T-lymphoma/leukemia, but unexpicably much lower than the 50-60% of other major endemic zones of Japan and the African descendants of the Caribeean. This report describes the clinical, laboratory, and epidemiological features of leukemia and lymphoma cases diagnosed between 1982 and 1984 in the city of Ibadan, Nigeria, some of the features of which are reminiscent of the observations of Ludwig Gross’s experiments on environmental influences, such as malnutrition and infections, on animal leukemogenesis. These events are the consequences of the primordial pressures that have shaped human genetics and pathophysiology. Evidence provided in this study, indicating association of increasing socioeconomic status with increasing frequency of the c-ALL subtype, is indicative of the prospects for leukemogenesis of acute lymphoblastic leukemia and its epidemiology in Nigerians. Some findings reported here indicate the influence of the African genetic ancestry in the etiology of acute myelogenous leukemia, while socioecomic status is linked to the etiology of childhood acute lymphoblastic leukemia, as well as a variant of chronic lymphocytic leukemia, and the chloroma-associated acute myelogenous leukemia. These observations are suggestive of the existence of pathways to etiological discoveries in the leukemias. Observations reviewed in this paper reflect examples of changes that have occurred over the past 200 years in the societal perception of health challenges among the new-found communities of colonial Africa and the Americas - from the reductionistic connotations such as in the “virgin-soil theory” - towards that of social determinants of health.

Abstract Adipose tissue plays a critical role in breast cancer incidence, progression, and response to therapy. The development of human derived 3D culture systems can accelerate the understanding of the role of environmental factors in the progression of Breast cancer as well as a model for preclinical studies during drug development. MCF-7 spheroids were cultured in Obatala Sciences’ Obavate and human-derived hydrogels ObaGel® and ObaGel®-ECM and control media. Organoid structure and phenotypic changes were analyzed via live cell imaging on the Incucyte S3. Migration studies were performed and gene expression analysis of EMT markers. Finally, adipocyte-breast cancer cell crosstalk was evaluated using pooled adipocytes co-cultured with MCF-7 spheroids. The results demonstrated that ObaGel® and ObaGel®-ECM 3D cultures support the growth and proliferation of MCF-7 tumorspheres during an extended culture period. In addition, MCF-7 cells exhibit the characteristic morphology of tumorsphere-forming cells when cultured in Obavate, with morphological changes in the ObaGel® and ObaGel®-ECM 3D. ObaGel® and ObaGel®-ECM differentially supports MCF-7 migratory behavior and phenotypic changes characteristic of EMT. Conclusions: Human derived hydrogels are developed to support 3D culture of breast cancer cells and to recapitulate the phenotypic changes associated with their metastatic potential. Furthermore, the use of a human derived 3D coculture system provides a platform for the understanding of adipose tissue-breast cancer cell interactions as it relates to breast cancer initiation, progression, and treatment response. Defining these interactions will support the development of a tool for future use in patient stratification and precision medicine in identifying underlying causes of breast cancer progression and response to treatments. Citation Format: Cecilia G. Sanchez, Katie Hamel, Emma Rogers, Jordan Robinson, Haley Lassiter, Trivia Frazier, Christopher Williams. Human-derived hydrogels to support phenotypic changes in ER+ breast cancer cell line [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4227.

One of the hallmarks of cancer is high levels of DNA replication stress and defects in the DNA damage response (DDR) pathways, which are critical for maintaining genomic integrity. Ataxia telangiectasia and Rad3-related protein (ATR) is a key regulator of the DDR machinery and an attractive therapeutic target, with multiple ATR inhibitors holding significant promise in ongoing clinical studies. Herein, we describe the discovery and characterization of ART0380 (6), a potent and selective ATR inhibitor with a compelling in vitro and in vivo pharmacological profile currently undergoing Phase 2 clinical studies in patients with advanced or metastatic solid tumors as monotherapy and in combination with DNA-damaging agents (NCT04657068 and NCT05798611). ART0380 (6) has a favorable human PK profile suitable for both intermittent and continuous once-daily (QD) dosing, characterized by a dose-proportional increase in exposure and low variability.

Aberrant estrogen receptor (ERα) signaling mediates detrimental effects of tamoxifen including drug resistance and endometrial hyperplasia. ERα36, an alternative isoform of ERα, contributes to these effects. We have demonstrated that CK2 modulates ERα expression and function in breast cancer (BCa). Here, we assess if CX-4945 (CX), a clinical stage CK2 inhibitor, can disrupt ERα66 and ERα36 signaling in BCa. Using live cell imaging, we assessed the antiproliferative effects of CX in tamoxifen-sensitive and tamoxifen-resistant BCa cells in monolayer and/or spheroid cultures. CX-induced alterations in ERα66 and ERα36 mRNA and protein expression were assessed by RT-PCR and immunoblot. Co-immunoprecipitation was performed to determine the differential interaction of ERα isoforms with HSP90 and CK2 upon CX exposure. CX caused concentration-dependent decreases in proliferation in tamoxifen-sensitive MCF-7 and tamoxifen-resistant MCF-7 Tam1 cells and significantly repressed spheroid growth in 3D models. Additionally, CX caused dramatic decreases in endogenous or exogenously expressed ERα66 and ERα36 protein. Silencing of CK2β, the regulatory subunit of CK2, resulted in destabilization and decreased proliferation, similar to CX. Co-immunoprecipitation demonstrated that ERα66/36 show CK2 dependance for interaction with molecular chaperone HSP90. Our findings show that CK2 functions regulate the protein stability of ERα66 and ERα36 through a mechanism that is dependent on CK2β subunit and HSP90 chaperone function. CX may be a component of a novel therapeutic strategy that targets both tamoxifen-sensitive and tamoxifen-resistant BCa, providing an additional tool to treat ERα-positive BCa.

Introduction:Many breast cancer therapeutics target the PI3K/AKT/mTOR oncogenic pathway. Development of resistance to the therapeutics targeting this pathway is a frequent occurrence. Therapeutics targeting p70S6K1, a downstream member of this pathway, have recently gained importance due to its critical role in all types of breast cancer and its status as a prognostic marker. We have developed a new class of p70S6K1 inhibitors that show growth inhibition of MCF7 breast cancer cells. Methods:A series of 6-amido-4-aminoisoindolyn-1,3-dione compounds was developed against p70S6K1 using docking, computational modeling tools, and synthesis of the designed compounds. The p70S6K1 inhibition potency of the compounds was investigated in an initial high-throughput screening followed by IC50 determination for the most active ones. The best compounds were subjected to proliferation assays on MCF7 breast cancer cells. The targeting of p70S6K1 by the compounds was confirmed by studying the phosphorylation status of downstream protein rpS6. Results:In this study, we have identified a new class of compounds as p70S6K1 inhibitors that function as growth inhibitors of MCF7 breast cancer cells. The structural features imparting p70S6K1 inhibition potency to the compounds have been mapped. Our studies indicate that substitutions on the phenacetyl group residing in the cleft A of the protein do not contribute to the inhibition potency. Three compounds (5b, 5d, and 5f) have been identified to have sub-micromolar inhibition potency for p70S6K1. These compounds also exhibited growth inhibition of MCF7 cells by 40%-60% in the presence of estradiol.

Supplementary Materials and Methods Supplementary References Tables S1 to S3 and legends Figures S1 to S4 and legends

Aromatase inhibitors (AIs) are standard treatment for estrogen-dependent postmenopausal breast tumors; however, resistance develops leading to tumor relapse and metastasis. We previously demonstrated that glyceollin inhibits proliferation, survival, and migration of hormone-independent letrozole-resistant breast cancer. Since many AI-resistant tumors remain hormone-dependent, identifying distinctions between estrogen-receptor-positive (ER+) and ER-negative (ER-) AI-resistant tumor response to therapy is critical. We hypothesize that treating ER+ letrozole-resistant T47D breast cancer cells (T47DaromLR) with a combination of 10 μM glyceollin and 0.5 μM lapatinib (a dual EGFR/HER2 inhibitor) will decrease cell proliferation through induction of apoptosis. The T47DaromLR cells were found to overexpress HER2 and MAPK while maintaining aromatase and ER levels compared to their letrozole-sensitive (T47Darom) counterparts. In the absence of estrogen stimulation, glyceollin ± lapatinib had no effect on the proliferation of the T47Darom cells, while glyceollin treatment caused 46% reduction in the proliferation of T47DaromLR cells, which was further diminished when combined with lapatinib. While neither agent influenced cell migration, glyceollin and lapatinib reduced S and G2/M phase cell entry and exclusively induced apoptosis by 1.29-fold in the T47DaromLR cells. Taken together, these results suggest that glyceollins and lapatinib may have potential as a novel combination therapeutic approach for hormone-dependent, letrozole-resistant tumors.

Breast carcinoma (BCa) remains the second most common cause of cancer-related death among American women. Whereas estrogen receptor (ER) expression is typically regarded as a favorable prognostic indicator, a significant proportion of ER(+) patients still experience either de novo or acquired endocrine resistance. Previously, we have shown that the loss of orphan nuclear receptor NURR1 expression is associated with neoplastic transformation of the breast epithelium and shorter relapse-free survival (RFS) among systemically treated breast cancer (BCa) patients. Here, we further ascertain the prognostic value of NURR1 in BCa, and its differential expression among Black and White female BCa patients. We assessed the expression of NURR1 mRNA in BCa patients using the Cancer Genome Atlas (TGCA) and compared the occurrence of basal-like cancer and luminal A breast cancer subtypes. Expression levels were further stratified according to racial identity of the patient. We next assessed the correlation of NURR1 expression with Oncotype DX prognostic markers, and the association of NURR1 expression with relapse free survival in patients treated with endocrine therapy. Our study shows that NURR1 mRNA expression is differentially correlated with luminal A vs. basal-like cancer BCa and is predictive of poor relapse-free survival, confirming a similar trend observed in our previous studies using microarray data. NURR1 expression was positively correlated with expression of Oncotype DX biomarkers associated with estrogen responsiveness, while being inversely correlated with biomarkers associated with cell proliferation. Furthermore, we observed that NURR1 expression was positively associated with greater relapse-free survival at 5 years among patients treated with endocrine therapy. Interestingly, we found that among Black women with luminal A BCa, NURR1 expression was repressed in comparison to White women with the same subtype.

Currently, more than 3.8 million women in the United States are diagnosed with breast cancer which is the second leading cause of cancer-related death in women. The correlation of the ribosomal protein S6 kinase 1 (S6K1) activity and breast cancer is evident from the amplification of S6K1 localized chromosomal region 17q23 in 20% of primary breast cancers. S6K1 is a conserved serine/threonine protein kinase, is the principal kinase effector downstream of the PI3K/mTOR regulatory signaling pathway. Over-expression of S6K1 has been associated with cell transformation and elevated proliferation rates in tumors, poor prognosis and an increased risk of local recurrence. S6K1 has been found to play an important role in the progression of ER-positive (ER+) breast cancer, HER2 positive (HER2+) breast cancer and node-negative premenopausal breast cancer. Inhibition of this kinase can prove to be beneficial for the treatment of several types of breast cancer. Our group has identified new molecules that are derivatives of 6-amido-4-aminoisoindoline-1,3-dione core structure as S6K1 inhibitors with low micromolar inhibition potency (IC50 = 2-5 μM). These compounds also inhibited the growth of HER2+ (SKBR3 and HER2Δ16), ER+ and triple negative breast cancer cells (MDA-MB-231 and MDA-MB-468) with a range of EC50 values (2 - 2000 μM). The EC50 values of growth inhibition of these compounds varied by the type of breast cancer cells and were in direct correlation with the expression levels of S6K1 in those cell lines. These results clearly indicate that high efficacy S6K1 inhibitors can function as potential therapeutics for multiple types of breast cancer. Future work involves in-vivo studies to understand the efficacy and pharmacokinetics of the three compounds. Citation Format: Satyendra Kumar, Rajesh Komati, Shahensha Shaik, Melyssa Bratton, Linh Tran, Rion Sam, Elijah Johnson-Henderson, Breyanah Graham, Christopher WIlliams, Jayalakshmi Sridhar. New derivatives of 1,3-dioxoisoindoline: Potential breast cancer therapeutics that are S6K1 inhibitors [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 343.

Src homology 2 (SH2) domain-containing phosphatase 2 (SHP2) plays a role in receptor tyrosine kinase (RTK), neurofibromin-1 (NF-1), and Kirsten rat sarcoma virus (KRAS) mutant-driven cancers, as well as in RTK-mediated resistance, making the identification of small-molecule therapeutics that interfere with its function of high interest. Our quest to identify potent, orally bioavailable, and safe SHP2 inhibitors led to the discovery of a promising series of pyrazolopyrimidinones that displayed excellent potency but had a suboptimal in vivo pharmacokinetic (PK) profile. Hypothesis-driven scaffold optimization led us to a series of pyrazolopyrazines with excellent PK properties across species but a narrow human Ether-à-go-go-Related Gene (hERG) window. Subsequent optimization of properties led to the discovery of the pyrimidinone series, in which multiple members possessed excellent potency, optimal in vivo PK across species, and no off-target activities including no hERG liability up to 100 μM. Importantly, compound 30 (IACS-15414) potently suppressed the mitogen-activated protein kinase (MAPK) pathway signaling and tumor growth in RTK-activated and KRASmut xenograft models in vivo.

International regulatory agencies such as the Food and Drug Administration have mandated that the scientific community develop humanized microphysiological systems (MPS) as an in vitro alternative to animal models in the near future. While the breast cancer research community has long appreciated the importance of three-dimensional growth dynamics in their experimental models, there are remaining obstacles preventing a full conversion to humanized MPS for drug discovery and pathophysiological studies. This perspective evaluates the current status of human tissue-derived cells and scaffolds as building blocks for an "idealized" breast cancer MPS based on bioengineering design principles. It considers the utility of adipose tissue as a potential source of endothelial, lymphohematopoietic, and stromal cells for the support of breast cancer epithelial cells. The relative merits of potential MPS scaffolds derived from adipose tissue, blood components, and synthetic biomaterials is evaluated relative to the current "gold standard" material, Matrigel, a murine chondrosarcoma-derived basement membrane-enriched hydrogel. The advantages and limitations of a humanized breast cancer MPS are discussed in the context of in-process and destructive read-out assays. Impact statement Regulatory authorities have highlighted microphysiological systems as an emerging tool in breast cancer research. This has been led by calls for more predictive human models and reduced animal experimentation. This perspective describes how human-derived cells, extracellular matrices, and hydrogels will provide the building blocks to create breast cancer models that accurately reflect diversity at multiple levels, that is, patient ethnicity, pathophysiology, and metabolic status.

Obesity, defined as a body mass index of 30 kg/m2 or above, has increased considerably in incidence and frequency within the United States and globally. Associated comorbidities including cardiovascular disease, type 2 diabetes mellitus, metabolic syndrome, and nonalcoholic fatty liver disease have led to a focus on the mechanisms promoting the prevention and treatment of obesity. Commonly utilized in vitro models employ human or mouse preadipocyte cell lines in a 2-dimensional (2D) format. Due to the structural, biochemical, and biological limitations of these models, increased attention has been placed on “organ on a chip” technologies for a 3-dimensional (3D) culture. Herein, we describe a method employing cryopreserved primary human stromal vascular fraction (SVF) cells and a human blood product-derived biological scaffold to create a 3D adipose depot in vitro. The “fat-on-chip” 3D cultures have been validated relative to 2D cultures based on proliferation, flow cytometry, adipogenic differentiation, confocal microscopy/immunofluorescence, and functional assays (adipokine secretion, glucose uptake, and lipolysis). Thus, the in vitro culture system demonstrates the critical characteristics required for a humanized 3D white adipose tissue (WAT) model.

Abstract Src homology 2 domain-containing phosphatase (SHP2) is a phosphatase that mediates signaling downstream of multiple receptor tyrosine kinases (RTK) and is required for full activation of the MAPK pathway. SHP2 inhibition has demonstrated tumor growth inhibition in RTK-activated cancers in preclinical studies. The long-term effectiveness of tyrosine kinase inhibitors such as the EGFR inhibitor (EGFRi), osimertinib, in non–small cell lung cancer (NSCLC) is limited by acquired resistance. Multiple clinically identified mechanisms underlie resistance to osimertinib, including mutations in EGFR that preclude drug binding as well as EGFR-independent activation of the MAPK pathway through alternate RTK (RTK-bypass). It has also been noted that frequently a tumor from a single patient harbors more than one resistance mechanism, and the plasticity between multiple resistance mechanisms could restrict the effectiveness of therapies targeting a single node of the oncogenic signaling network. Here, we report the discovery of IACS-13909, a specific and potent allosteric inhibitor of SHP2, that suppresses signaling through the MAPK pathway. IACS-13909 potently impeded proliferation of tumors harboring a broad spectrum of activated RTKs as the oncogenic driver. In EGFR-mutant osimertinib-resistant NSCLC models with EGFR-dependent and EGFR-independent resistance mechanisms, IACS-13909, administered as a single agent or in combination with osimertinib, potently suppressed tumor cell proliferation in vitro and caused tumor regression in vivo. Together, our findings provide preclinical evidence for using a SHP2 inhibitor as a therapeutic strategy in acquired EGFRi-resistant NSCLC. Significance: These findings highlight the discovery of IACS-13909 as a potent, selective inhibitor of SHP2 with drug-like properties, and targeting SHP2 may serve as a therapeutic strategy to overcome tumor resistance to osimertinib.

Community pharmacists assist patients to manage disease and prevent complications. Despite the enormous challenge the coronavirus disease 2019 (COVID-19) pandemic has dealt to the health care system, community pharmacists have maintained the delivery of critical health services to communities, including those most at risk for COVID-19. Community pharmacists are in a key position to deliver priority pandemic responses including point-of-care testing for chronic disease management, vaccinations, and COVID-19 testing.

The obesity epidemic and its associated comorbidities present a looming challenge to health care delivery throughout the world. Obesity is characterized as a sterile inflammatory process within adipose tissues leading to dysregulated secretion of bioactive adipokines such as adiponectin and leptin, as well as systemic metabolic dysfunction. The majority of current obesity research has focused primarily on preclinical animal models in vivo and two-dimensional cell culture models in vitro. Neither of these generalized approaches is optimal due to interspecies variability, insufficient accuracy with respect to predicting human outcomes, and failure to recapitulate the three-dimensional (3D) microenvironment. Consequently, there is a growing demand and need for more sophisticated microphysiological systems to reproduce more physiologically accurate human white and brown/beige adipose depots. To address this research need, human and murine cell lines and primary cultures are being combined with bioscaffolds to create functional 3D environments that are suitable for metabolically active adipose organoids in both static and perfusion bioreactor cultures. The development of these technologies will have considerable impact on the future pace of discovery for novel small molecules and biologics designed to prevent and treat metabolic syndrome and obesity in humans. Furthermore, when these adipose tissue models are integrated with other organ systems they will have applicability to obesity-related disorders such as diabetes, nonalcoholic fatty liver disease, and osteoarthritis. Impact statement The current review article summarizes the advances made within the organ-onchip field, as it pertains to adipose tissue models of obesity and obesity-related syndromes, such as diabetes, non-alcoholic fatty liver disease, and osteoarthritis. As humanized 3D adipose-derived constructs become more accessible to the research community, it is anticipated that they will accelerate and enhance the drug discovery pipeline for obesity, diabetes, and metabolic diseases by reducing the preclinical evaluation process and improving predictive accuracy. Such developments, applications, and usages of existing technologies can change the paradigm of personalized medicine and create substantial progress in our approach to modern medicine.

Background: Several mechanisms of action have been proposed to explain the apparent antineoplastic functions of metformin, many of which are observed at high concentrations that may not be reflective of achievable tissue concentrations. We propose that metformin at low concentrations functions to inhibit ROS production and inflammatory signaling in breast cancer, thereby reducing metastasis. Methods: Using the highly invasive MDA-MB-231 breast carcinoma model, we ascertained the impact of metformin on cell viability by DNA content analysis and fluorescent dye exclusion. Migration and invasion assays were performed using a modified Boyden chamber assay and metastasis was ascertained using the chorioallantoic membrane (CAM) assay. PGE2 production was measured by Enzyme-Linked Immunosorbent Assay (ELISA). COX2 and ICAM1 levels were determined by flow cytometry immunoassay. Results: Metformin acutely decreased cell viability and caused G2 cell cycle arrest only at high concentrations (10 mM). At 100 µM, however, metformin reduced ICAM1 and COX2 expression, as well as reduced PGE2 production and endogenous mitochondrial ROS production while failing to significantly impact cell viability. Consequently, metformin inhibited migration, invasion in vitro and PGE2-dependent metastasis in CAM assays. Conclusion: At pharmacologically achievable concentrations, metformin does not drastically impact cell viability, but inhibits inflammatory signaling and metastatic progression in breast cancer cells.