Biology subjects

Kaseb, A. O.

Publications and source records attributed to Kaseb, A. O..

4 recordsLinked to original sources

bioRxiv2025

Spatial multi-omics and deep learning reveal fingerprints of immunotherapy response and resistance in hepatocellular carcinoma

Despite advances in immunotherapy treatment, nonresponse rates remain high, and mechanisms of resistance to checkpoint inhibition remain unclear. To address this gap, we performed spatial transcriptomic and proteomic profiling on human hepatocellular carcinoma tissues collected before and after immunotherapy. We developed an interpretable, multimodal deep learning framework to extract key cellular and molecular signatures from these data. Our graph neural network approach based on spatial proteomic inputs achieved outstanding performance (ROC-AUC > 0.9) in predicting patient treatment response. Key predictive features and associated spatial transcriptomic profiles revealed the multi-omic landscape of immunotherapy response and resistance. One such feature was an interface niche expressing restrictive extracellular matrix factors that physically separates tumor tissue and lymphoid aggregates in nonresponders. We integrate this and other spatially-resolved signatures into SPARC, a multi-omic "fingerprint" comprising scores for immunotherapy response and resistance mechanisms. This study lays groundwork for future patient stratification and treatment strategies in cancer immunotherapy.

cancer biology↗

bioRxiv2025

Somatostatin Receptor 2 Overexpression in Hepatocellular Carcinoma: Implications for Cancer Biology and Theranostic Applications

(1) BackgroundSomatostatin receptor 2 (SSTR2) is overexpressed in various tumors, including hepatocellular carcinoma (HCC), yet its role in tumorigenesis remains unclear. This study examines the roles of SSTR2 in the molecular pathology of HCC and explores its potential as a target for SSTR2-directed radiopharmaceuticals in this malignancy. (2) MethodsSSTR2 expression was analyzed across 22 malignancies using TNMplot and specifically in HCC through The Human Protein Atlas. Transcriptomic data, protein expression, and copy number alterations in HCC patients with varying SSTR2 levels were compared using The Cancer Genome Atlas (TCGA). Gene Ontology (GO) enrichment analysis was performed using SRplot, while survival analysis was conducted with GEO datasets. (3) ResultsMost HCC patients exhibit moderate levels of SSTR2 expression. Elevated SSTR2 expression is associated with worse overall and disease-specific survival, as well as the activation of pathways involved in tumor growth and metastasis. Furthermore, SSTR2 expression is linked to key oncogenes and receptor tyrosine kinases. (4) ConclusionsSSTR2 in HCC signifies an oncogenic network and represents a promising therapeutic target to inhibit tumor invasion and serve as a theranostic biomarker. HCC patients with elevated SSTR2 expression could benefit from SSTR2-targeted theranostics, enabling enhanced tumor detection and more effective therapy.

cancer biology↗

bioRxiv2024

SSTR2-targeted theranostics in hepatocellular carcinoma

(1) BackgroundWhile the clinical use of radiolabeled somatostatin analogs is established in neuroendocrine tumors, there is significant interest in expanding their use for other somatostatin receptor 2 (SSTR2)-expressing cancers. This study investigates the utility of SSTR2-targeted theranostics in hepatocellular carcinoma (HCC); (2) MethodsWe measured SSTR2 expression in HCC cell lines and clinical samples using qRT-PCR, Western blot, and a public dataset. We evaluated [67Gallium]Ga-DOTATATE uptake, tested [177Lutetium]Lu-DOTATATE cytotoxicity, and assessed [68Gallium]Ga-DOTATATE tumor targeting in HCC animal models and a patient via PET/CT; (3) ResultsSSTR2 expression was confirmed in HCC cell lines and clinical samples. Radioligand uptake studies validated SSTR2-mediated [67Gallium]Ga-DOTATATE uptake, and [177Lutetium]Lu-DOTATATE treatment reduced cell proliferation. [68Gallium]Ga-DOTATATE PET/CT scans detected tumors in animal models and spinal metastases in a patient with HCC; (4) ConclusionThese findings suggest for the first time that SSTR2-based theranostics could have strong implications for detection and treatment of HCC. Simple SummaryThis study investigates the use of SSTR2-targeted theranostics, combining diagnostic and therapeutic approaches, in hepatocellular carcinoma (HCC). We confirmed significant SSTR2 expression in HCC cells and patient samples, showing that radiolabeled compounds such as [67Ga]Ga-DOTATATE and [177Lu]Lu-DOTATATE, commonly used in neuroendocrine tumors, could also target HCC. In preclinical models and a patient case, PET/CT imaging and treatments demonstrated effective tumor detection and shrinkage. These findings suggest that SSTR2-targeted theranostics could offer a novel, targeted method for diagnosing and treating HCC, potentially improving outcomes for patients with this challenging cancer.

cancer biology↗

bioRxiv2023

Angiotensin II receptor inhibition ameliorates liver fibrosis and enhances hepatocellular carcinoma infiltration by effector T cells

Although viral hepatocellular carcinoma (HCC) is declining, non-viral HCC, which often is the end-stage of non-alcoholic or alcoholic steatohepatitis (NASH, ASH), is on an upward trajectory. Immune checkpoint inhibitors (ICI) that block the T cell inhibitory receptor PD-1 were approved for treatment of all HCC types. However, only a small portion of HCC patients show a robust and sustained response to PD-1 blockade, calling for improved understanding of factors that negatively impact response rate and duration and the discovery of new adjuvant treatments that enhance ICI responsiveness. Using a mouse model of NASH-driven HCC, we identified peritumoral fibrosis as a potential obstacle to T cell mediated tumor regression and postulated that anti-fibrotic medications may increase ICI responsiveness. We now show that the angiotensin II receptor inhibitor losartan, a commonly prescribed and safe antihypertensive drug, reduced liver and peritumoral fibrosis and substantially enhanced anti-PD-1 induced tumor regression. Although losartan did not potentiate T cell reinvigoration, it substantially enhanced HCC infiltration by effector CD8+ T cells compared to PD-1 blockade alone. The beneficial effects of losartan correlated with inhibition of TGF-{beta} receptor signaling, collagen deposition and depletion of immunosuppressive fibroblasts. SignificanceImmune checkpoint inhibitors are used in HCC treatment but overall response rates for single agent PD-1/PD-L1 blockers have remained stubbornly low. Using a mouse model of NASH-driven HCC, we show that co-treatment with the safe and inexpensive angiotensin II receptor inhibitor losartan substantially enhanced anti-PD-1 triggered HCC regression. Although losartan did not influence the reinvigoration of exhausted CD8+ T cells it considerably enhanced their intratumoral invasion, which we postulated to be compromised by peritumoral fibrosis. Indeed, the beneficial effect of losartan correlated with inhibition of TGF-{beta} signaling and collagen deposition, and depletion of immunosuppressive fibroblasts. Losartan should be evaluated for its adjuvant activity in HCC patients undergoing PD-1/PD-L1 blocking therapy.

cancer biology↗