Carrano, Anna

Abstract Glioma stem cells (GSCs) are considered a major driver of glioblastoma (GBM) progression and are highly resistant to standard cytotoxic treatments. BMP4 has been shown to promote GSC differentiation, enhance radiosensitivity, slow tumor growth, and extend survival in animal models. Despite this promise, BMP4 has yet to achieve clinical impact, owing largely to heterogeneous and nonlinear responses across preclinical experimental systems. To elucidate how BMP4 could function as an effective targeted differentiation therapy in GBM, we develop a mathematical model that describes the growth of a GBM tumor via a hierarchy of GSCs, progenitor and terminally differentiated cells. We parameterize our model using new radiotherapy and proliferation assay data (with and without BMP4 exposure) from twelve patient-derived GSC lines. This integration of model and data allows us, for the first time, to quantitatively capture patient-specific heterogeneity in BMP4 sensitivity. We perform global sensitivity analysis on the model, identifying proliferation rate and GSC self-renewal sensitivity as key determinants of BMP4 efficacy. These parameters act as model-derived biomarkers that distinguish BMP4-responsive tumors from non-responsive ones. In an in silico analysis across a broad cohort of virtual patients, we find that continuous BMP4 delivery from surgical resection through radiotherapy consistently outperforms a single-dose strategy. Virtual clinical trials further show that, without stratification using these model-derived biomarkers, BMP4 yields little observable therapeutic benefit. In contrast, selecting patients with more proliferative, BMP4-responsive GSCs markedly increases the likelihood of observing a significant treatment effect. Citation Format: Nicholas Harbour, Lee Curtin, Loizos Michaelides, Matthew E. Hubbard, Pamela Jackson, Vinitha Rani, Rajappa Kenchappa, Virginea Farias, Anna Carrano, Markus Owen, Alfredo Quinones-Hinojosa, Kristin Swanson. Virtual clinical trials of BMP4 differentiation therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2026; Part 1 (Regular Abstracts); 2026 Apr 17-22; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2026;86(7 Suppl):Abstract nr 6831.

Abstract Glioblastoma (GBM) is the most common malignant primary brain tumor in adults with a median survival of 8-14 months and 5-year survival rate of 6.9%. Its aggressive nature arises mostly from molecular heterogeneity and resistance to standard of care (SOC), including radiation and temozolomide (TMZ). Recurrence is nearly inevitable, driven by highly invasive brain tumor initiating cells (BTICs). Our previous studies revealed that exposing BTICs to cerebrospinal fluid (CSF) from GBM patients increases cell migration and proliferation compared to non-cancer CSF. Transcriptomic analysis identified the upregulation of the SERPINA3 gene, which encodes alpha-1-antichymotrypsin (ACT). Silencing of SERPINA3 reduces BTIC migration and proliferation and abolishes the promigratory response to GBM-derived CSF, highlighting SERPINA3 as a potential therapeutic target. ACT has been reported to bind to DNA, although the implications of this interaction are unknown. We have previously observed higher levels of intranuclear ACT in human GBM compared to non-cancer brain tissues. We hypothesize that the nuclear localization of SERPINA3 in GBM contributes to increased malignancy, opening the possibility of therapeutically targeting its intranuclear transport. Here, we determined the intracellular localization of ACT in BTICs and GBM and compared it to non-cancer tissues. Additionally, we evaluated whether SOC affected intranuclear localization of ACT. Patient-derived BTICs were treated with TMZ, radiation, and a combination of both, to assess changes in ACT expression via Western Blot, PCR, and ICC. A decrease in cell confluency was correlated with a significant decrease (p<0.05) in SERPINA3 mRNA and overall protein expression when BTICs were treated with TMZ alone or in combination. Interestingly, confocal microscopy revealed a significant increase (p<0.05) in its nuclear localization, particularly with TMZ treatment, indicating a change in its intracellular distribution. Overall, nuclear translocation of SERPINA3 increases in response to SOC with potential implications as a treatment resistance mechanism.

Glioblastoma (GBM) is the most prevalent and aggressive malignant primary brain tumor. GBM proximal to the lateral ventricles (LVs) is more aggressive, potentially because of subventricular zone contact. Despite this, cross-talk between GBM and neural stem/progenitor cells (NSC/NPCs) is not well understood. Using cell-specific proteomics, we show that LV-proximal GBM prevents neuronal maturation of NSCs through induction of senescence. In addition, GBM brain tumor–initiating cells (BTICs) increase expression of cathepsin B (CTSB) upon interaction with NPCs. Lentiviral knockdown and recombinant protein experiments reveal that both cell-intrinsic and soluble CTSB promote malignancy-associated phenotypes in BTICs. Soluble CTSB stalls neuronal maturation in NPCs while promoting senescence, providing a link between LV-tumor proximity and neurogenesis disruption. Last, we show LV-proximal CTSB up-regulation in patients, showing the relevance of this cross-talk in human GBM biology. These results demonstrate the value of proteomic analysis in tumor microenvironment research and provide direction for new therapeutic strategies in GBM.

Abstract Glioblastoma (GBM) is the most common primary brain cancer in adults where tumor cell heterogeneity and sex differences influence clinical outcomes. Here, we functionally characterize three male and three female patient-derived GBM cell lines, identify protumorigenic BTICs, and create novel male and female preclinical models of GBM. Cell lines were evaluated on the following features: proliferation, stemness, migration, tumorigenesis, clinical characteristics, and sensitivity to radiation, TMZ, rhTNFSF10 (rhTRAIL), and rhBMP4. All cell lines were classified as GBM according to epigenetic subtyping, were heterogenous and functionally distinct from one another, and re-capitulated features of the original patient tumor. In establishing male and female preclinical models, it was found that two male-derived GBM cell lines (QNS108 and QNS120) and one female-derived GBM cell line (QNS315) grew at a faster rate in female mice brains. One male-derived GBM cell line (QNS108) decreased survival in female mice in comparison with male mice. However, no survival differences were observed for mice injected with a female-derived cell line (QNS315). In summary, a panel of six GBM patient-derived cell lines were functionally characterized, and it was shown that BTIC lines can be used to construct sex-specific models with differential phenotypes for additional studies.

Sex differences have been well identified in many brain tumors. Even though glioblastoma (GBM) is the most common primary malignant brain tumor in adults and has the worst outcome, well-established differences between men and women are limited to incidence and outcome. Little is known about sex differences in GBM at the disease phenotype and genetical/molecular level. This review focuses on a deep understanding of the pathophysiology of GBM, including hormones, metabolic pathways, the immune system, and molecular changes, along with differences between men and women and how these dimorphisms affect disease outcome. The information analyzed in this review shows a greater incidence and worse outcome in male patients with GBM compared with female patients. We highlight the protective role of estrogen and the upregulation of androgen receptors and testosterone having detrimental effects on GBM. Moreover, hormones and the immune system work in synergy to directly affect the GBM microenvironment. Genetic and molecular differences have also recently been identified. Specific genes and molecular pathways, either upregulated or downregulated depending on sex, could potentially directly dictate GBM outcome differences. It appears that sexual dimorphism in GBM affects patient outcome and requires an individualized approach to management considering the sex of the patient, especially in relation to differences at the molecular level.

Abstract Introduction: Glioblastoma (GBM) is the most common and malignant primary brain tumor in adults. The interaction of GBM with the lateral ventricles (LVs) has a significant effect on patient outcome, where LV-proximal GBM results in increased distal recurrence, increased stem cell marker expression, and decreased overall survival compared to LV-distal counterparts. Though the reason for this is unknown, it may be due in part to interaction of GBM with the subventricular zone (SVZ), the largest neurogenic niche. The SVZ contains populations of neural stem cells (NSCs) throughout life that produce many proteins supporting stem cell growth and maintenance. The goal of this project is to identify a bidirectional signaling axis between GBM cells and NSCs and determine its contribution to GBM malignancy. Methods: In vitro, patient-derived GBM brain tumor initiating cells (BTICs) were co-cultured with human fetal NSCs for 48 hours. Both BTICs and NSCs were analyzed for levels of viability, proliferation, migration, and the expression of malignancy-associated factors at a gene and protein level. A method for unbiased cell-specific proteomic labeling was established in vitro by cloning L274G-mutated methionyl tRNA synthetase (MetRS*) into a lentivirus with puromycin resistance. In vivo, Nestin-Cre-ERT2 mice were crossed with the STOPflox R26-MetRS line to establish a tamoxifen-inducible model to label NSC proteins. Results: BTICs co-cultured with NSCs showed increased viability, proliferation, and migration compared to controls. NSCs showed decreased proliferation and increased migration when co-cultured with BTICs. Both show increased levels of malignancy-associated genes and proteins including osteopontin, vimentin, tenascin C, and PDGFA upon co-culture. MetRS*-labeled cells successfully incorporate azide-labeled methionine analog in a cell-specific manner, and labeled proteins are able to be isolated for future proteomic analysis. In vivo, tamoxifen successfully induces the expression of MetRS* and GFP. Conclusion: We have determined that there is a bidirectional signaling axis between NSCs and BTICs that contributes to proliferation, migration, and malignancy-associated factors in GBM. Future studies looking at proteomic changes in both GBM and NSCs using the MetRS* labeling are needed to fully characterize the interaction between these cells in vitro and in vivo to identify new therapeutic targets for LV-associated GBM. Citation Format: Emily S. Norton, Lauren A. Whaley, Anna Carrano, Natanael Zarco, Montserrat A. Lara-Velazquez, Alfredo Quinones-Hinojosa, Hugo Guerrero-Cazares. Exploring the malignancy-promoting interaction between neural stem cells and lateral ventricle-associated glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 3073.

Abstract Background Glioblastomas (GBMs) are the main primary brain tumors in adults with almost 100% recurrence rate. Patients with lateral ventricle proximal GBMs (LV-GBMs) exhibit worse survival compared to distal locations for unknown reasons. One hypothesis is the proximity of these tumors to the cerebrospinal fluid (CSF) and its chemical cues that can regulate cellular phenotype. We therefore investigated the role of CSF on GBM gene expression and the role of a CSF-induced gene, SERPINA3, in GBM malignancy in vitro and in vivo. Methods We utilized human CSF and GBM brain tumor-initiating cells (BTICs). We determined the impact of SERPINA3 expression in glioma patients using The Cancer Genome Atlas (TCGA) database. SERPINA3 expression changes were evaluated at mRNA and protein levels. The effects of knockdown (KD) and overexpression (OE) of SERPINA3 on cell migration, viability and cell proliferation were evaluated. Stem cell characteristics on KD cells were evaluated by differentiation and colony formation experiments. Tumor growth was studied by intracranial and flank injections. Results GBM-CSF increased BTIC migration accompanied by upregulation of the SERPINA3 gene. In patient samples and TCGA data, we observed SERPINA3 to correlate directly with brain tumor grade and indirectly with GBM patient survival. SERPINA3 KD induced a decrease in cell proliferation, migration, invasion, and stem cell characteristics, while SERPINA3 OE increased cell migration. In vivo, SERPINA3 KD BTICs showed increased survival in a murine model. Conclusions SERPINA3 plays a key role in GBM malignancy and its inhibition results in a better outcome using GBM preclinical models.

Abstract Glioblastoma (GBM) is the most common and aggressive primary brain tumor in adults with a median survival of 14 months despite multimodal treatment. Patients with GBM tumors exhibit a post-resection recurrence rate of almost 100%. The tumor recurrence and treatment resistance properties of GBM reside in a stem-like cell population called Brain Tumor Initiating Cells (BTIC). Among primary GBMs, periventricular tumors exhibit worse survival than tumors distal to the lateral ventricles (LV), the cause for this worse outcome is not known. A potential explanation is the proximity of these tumors to the cerebrospinal fluid (CSF) and the neurogenic niche in the sub-ventricular zone (SVZ). Chemotactic signals present in the cerebrospinal fluid (CSF) regulate neural progenitor cells migratory response and differentiation profile. Our preliminary data show that cancer-derived CSF induces an increase in the migration and proliferation of GBM cells when compared to non-cancer CSF. We evaluated the transcriptome of human GBM cells in response to cancer and non-cancer CSF and identified alpha-1-antichymotrypsin (SERPINA3) as one of the genes that show higher over expression upon cancer CSF-stimulation. SERPINA3 is a circulating anti-protease that is produced and released in different tissues such as liver, prostate, lungs, endometrium and brain that is over-expressed in multiple cancers. We hypothesize that the overexpression of SERPINA3 in response to CSF is a contributing factor to the increase malignancy of periventricular GBM tumors. We tested this hypothesis in silico, in vitro and in vivo. Using TCGA and Rembrandt databases we observed a higher expression of SERPINA3 in brain tumor tissue compared to controls with no differences among GBM subtypes. In GBM patients, expression of SERPINA3 negatively affects survival expectancy. In vitro, Using intraoperative samples, we confirmed that SERPINA3 is overexpressed in brain cancer tissue by western-blot and qRT-PCR. Interestingly, we observed a higher nuclear localization of SERPINA3 in cancer tissue and cells. To determine if SERPINA3 has an effect on the malignancy of GBM cells, we silenced its expression using shRNA. SERPINA3 silencing induced a decrease in cell proliferation (p<0.05), as well as migration (p<0.05), and invasion (p<0.05). Remarkably CD133 expression and stem cell markers were decreased when SERPINA3 is silenced. In contrast, the addition of recombinant SERPINA3 induced an increase in cell migration (p<0.05) of GBM cells. Moreover, cancer CSF is no longer able to induce an increase in GBM cell migration in SERPINA3-KD cells (p<0.05). In vivo, mice orthotopically-injected with SERPINA3-KD cells showed a prolonged overall survival (p<0.05). In summary, our results support the hypothesis that SERPINA3 plays a key role in GBM malignancy in response to CSF and its inhibition results in a better outcome using GBM preclinical models. Targeting the CSF-GBM interaction is a potential therapeutic approach that remains to be explored. Citation Format: Montserrat A. Lara Velazquez, Natanael Zarco, Anna Carrano, Jordan Phillips, Paula Schiapparelli, Emily S. Norton, Stephanie Jeanneret, Teresita Corona, Jose Segovia, Kaisorn Chaichana, Yan Asmann, Alfredo Quinones Hinojosa, Hugo Guerrero-Cazares. Cerebrospinal fluid-responsive factor SERPINA3 induces an increase in the malignancy of glioblastoma [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 3780.

Abstract Glioblastoma (GBM), also known as grade IV astrocytoma, is the most common and devastating primary cancer of the central nervous system in adults. Despite the most advanced therapeutic strategies combining surgery, chemotherapy, and radiation, survival expectancy of GBM patients averages 14 months, with a recurrence rate of almost 100%. Remarkably, tumor location has great implications in the prognosis of GBM. Approximately 50-60% of GBM tumors infiltrates or contacts the subventricular zone (SVZ). These patients have significantly worse outcomes, in terms of median overall survival, time to progression and reoccurrence. The reason for the worse prognosis of SVZ-infiltrating tumors is unknown. The SVZ is the largest neurogenic niche in the adult brain, here the differentiation and migration of SVZ cells is regulated by direct contact with the cerebrospinal fluid (CSF). We suggest that CSF contribute to enhance GBM malignant characteristics in SVZ-infiltrating tumors. This study evaluated the impact of CSF exposure on GBM cells proliferation, migration in vitro and in vivo, as well as changes in gene expression profile. We demonstrated that CSF affects the malignancy of GBM cells by increasing their ability to proliferate and migrate. GBM cells stimulated with cancer CSF, non-cancer CSF, or control conditions at different time points (24-72 hrs) were evaluated for viability (by Alamar Blue assay) and proliferation rate (Ki67+ immunostaining), as well as for migratory capabilities (by means of transwell assay and time-lapse microscopy). We recapitulated these CSF effects in vivo using an in vivo model in which both female and male nude mice were implanted with GBM cells in suspension with human cancer or non-cancer CSF in an hydrogel as vehicle (n=8 mice per group). Tumor growth was followed via IVIS imaging and then studied by measuring tumor area on H&E slides and immunohistochemistry staining for Ki67, 21 days after tumor implantation. Animals receiving cancer CSF presented with greater tumor size and Ki67 proliferation index. To further dissect the mechanisms behind these observations, we performed a transcriptome analysis of CSF-treated GBM cells. At the molecular level we observed that cancer CSF induced changes in pathways regulating apoptosis, survival, integrins signaling, angiogenesis, glucose metabolism and response to inflammatory stimuli, all of which might be responsible for the increase in GBM malignancy. Taken together, this study provides direct evidence that CSF is an important player in determining tumor growth and invasion through the activation of complex gene expression patterns characteristic of a malignant phenotype. Understanding the interaction of brain tumors and CSF may lead to new therapeutic strategies that will target the CSF components in GBM patients. Citation Format: Anna Carrano, Jordan Phillipps, Montserrat Lara-Velazquez, Natanael Zarco, Paola Suarez-Meade, Kaisorn Chaichana, Alfredo Quinones-Hinojosa, Yan Asmann, Hugo Guerrero-Cázares. The role of human cerebrospinal fluid in glioblastoma malignancy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1574.