The aberrant expression of HER family members and cancer stem cells (CSCs) have been associated with tumour progression and resistance to therapy. At present, several HER inhibitors have been approved for the treatment of patients with a range of cancers but not for the treatment of patients with hepatocellular carcinoma (HCC). The present study investigated the co‑expression and prognostic significance of HER family members, type‑III deletion mutant EGFR (EGFRvIII), and the putative CSC biomarkers CD44 and epithelial cell adhesion molecule (EpCAM) in 43 patients with HCC. The relative expression of these biomarkers was determined using immunohistochemistry. At a cut off value of >5% of tumour cells stained for these biomarkers, 35% [wild‑type (wt)EGFR], 58% (HER‑2), 0% (HER‑3), 19% (HER‑4), 26% (EGFRvIII), 40% (CD44) and 33% (EpCAM) of patients were positive. In 23, 14 and 9% of the patients, wtEGFR expression was accompanied by co‑expression with HER‑2, EGFRvIII and HER‑2/EGFRvIII, respectively. EGFRvIII expression, membranous expression of CD44 and co‑expression of wtEGFR/EGFRvIII were associated with poor overall survival (OS). By contrast, cytoplasmic CD44 expression was associated with a longer OS time. The present study also investigated the effect of several agents targeting one or more members of the HER family, other growth factor receptors and cell signalling proteins on the proliferation of HCC cell lines. Among agents targeting one or more members of the HER family, the pan‑HER family blocker afatinib was the most effective, inhibiting the proliferation of three out of seven human liver cancer cell lines (LCCLs), while the CDK inhibitor dinacicilib was the most effective agent, inhibiting the proliferation of all human LCCLs tested. Taken together, the present results suggested that EGFRvIII expression and its co‑expression with wtEGFR or CD44 was of prognostic significance. These results also support further investigations of the therapeutic potential of drugs targeting EGFRvIII and other members of the HER family in patients with HCC.

Of various human epidermal growth factor receptor (HER) inhibitors, only the anti-HER2 monoclonal antibody (mAb) Herceptin/trastuzumab and the antibody-drug conjugate trastuzumab deruxtecan (T-Dxd) has been approved for the treatment of patients with stomach cancer. However, the duration of response may be short in many patients, with tumor heterogeneity being one contributing factor.
We investigated the effect of various types of targeted agents on growth in vitro and migration of a panel of human stomach cancer cells (HSCCLs) and the impact of cell proliferation rate on the anti-tumor activities of these agents. We also investigated the association between the cell surface expression of the HER family members, hepatocyte growth factor receptor (c-Met), anaplastic lymphoma kinase (ALK)7 and cancer stem cell markers CD44 and CD133, and the response to the targeted agents.
Of the 18 agents examined, the cyclin dependent kinase (CDK) 1/2/5/9 inhibitor dinaciclib was the most effective and inhibited the growth of all human HSCCLs at 50% inhibitory concentration (IC50) values between 9 nM to 23 nM. Of various HER inhibitors, the irreversible pan-HER family inhibitors (e.g., afatinib) were more effective than the reversible dual epidermal growth factor receptor (EGFR)/HER2 tyrosine kinase inhibitor (TKI) lapatinib and the EGFR-specific TKI erlotinib in inhibiting the growth of HSCCLs. Of agents targeting different downstream cell signaling molecules, dasatinib targeting Ab1/Src/C-Kit, trametinib targeting MERK1/2 and miransertib targeting AKT1/2/3 inhibited growth of majority of HSCCLs, with the IC50 values ranging from 2 nM to 7 µM. Many of these agents were more effective in inhibiting the growth of HSCCLs when they were proliferating at a slower rate. Treatment with neratinib, afatinib, dinaciclib, dasatinib, stattic, miransertib and paclitaxel significantly inhibited migration of stomach cancer cells. Interestingly, treatment with a combination of afatinib and dasatinib or afatinib and miransertib resulted in synergistic and additive growth inhibition of stomach cancer cells.
These results suggest that treatment with a combination of these agents may be of therapeutic value in stomach cancer and warrants further investigations.
Copyright 2024, Al-Janaby et al.

Human dental pulp stem cells (hDPSCs) promote recovery after ischemic stroke; however, the therapeutic efficacy is limited by the poor survival of transplanted cells. For in vitro experiments in the present study, we used oxygen-glucose deprivation/reoxygenation in hDPSCs to mimic cell damage induced by ischemia/reperfusion. We found that miRNA-34a-5p (miR-34a) was elevated under oxygen-glucose deprivation/reoxygenation conditions in hDPSCs. Inhibition of miR-34a facilitated the proliferation and antioxidant capacity and reduced the apoptosis of hDPSCs. Moreover, dual-luciferase reporter gene assay showed WNT1 and SIRT1 as the targets of miR-34a. In miR-34a knockdown cell lines, WNT1 suppression reduced cell proliferation, and SIRT1 suppression decreased the antioxidant capacity. Together, these results indicated that miR-34a regulates cell proliferation and antioxidant stress via targeting WNT1 and SIRT1, respectively. For in vivo experiments, we injected genetically modified hDPSCs (anti34a-hDPSCs) into the brains of mice. We found that anti34a-hDPSCs significantly inhibited apoptosis, reduced cerebral edema and cerebral infarct volume, and improved motor function in mice. This study provides new insights into the molecular mechanism of the cell proliferation and antioxidant capacity of hDPSCs, and suggests a potential gene that can be targeted to improve the survival rate and efficacy of transplanted hDPSCs in brain after ischemic stroke.

Fibrolamellar carcinoma (FLC) is a lethal primary liver cancer, affecting young patients in absence of chronic liver disease. Molecular understanding of FLC tumorigenesis is limited, partly due to the scarcity of experimental models. Here, we CRISPR-engineer human hepatocyte organoids to recreate different FLC backgrounds, including the predominant genetic alteration, the DNAJB1-PRKACA fusion, as well as a recently reported background of FLC-like tumors, encompassing inactivating mutations of BAP1 and PRKAR2A. Phenotypic characterizations and comparisons with primary FLC tumor samples revealed mutant organoid-tumor similarities. All FLC mutations caused hepatocyte dedifferentiation, yet only combined loss of BAP1 and PRKAR2A resulted in hepatocyte transdifferentiation into liver ductal/progenitor-like cells that could exclusively grow in a ductal cell environment. BAP1-mutant hepatocytes represent primed cells attempting to proliferate in this cAMP-stimulating environment, but require concomitant PRKAR2A loss to overcome cell cycle arrest. In all analyses, DNAJB1-PRKACAfus organoids presented with milder phenotypes, suggesting differences between FLC genetic backgrounds, or for example the need for additional mutations, interactions with niche cells, or a different cell-of-origin. These engineered human organoid models facilitate the study of FLC.
© 2023. The Author(s).

Embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) have distinct origins: ESCs are derived from pre-implanted embryos while iPSCs are reprogrammed somatic cells. Both have their own characteristics and lineage specificity, and both are valuable tools for studying human neurological development and disease. Thus far, few studies have analyzed how differences between stem cell types influence mitochondrial function and mitochondrial DNA (mtDNA) homeostasis during differentiation into neural and glial lineages. In this study, we compared mitochondrial function and mtDNA replication in human ESCs and iPSCs at three different stages - pluripotent, neural progenitor and astrocyte. We found that while ESCs and iPSCs have a similar mitochondrial signature, neural and astrocyte derivations manifested differences. At the neural stem cell (NSC) stage, iPSC-NSCs displayed decreased ATP production and a reduction in mitochondrial respiratory chain (MRC) complex IV expression compared to ESC-NSCs. IPSC-astrocytes showed increased mitochondrial activity including elevated ATP production, MRC complex IV expression, mtDNA copy number and mitochondrial biogenesis relative to those derived from ESCs. These findings show that while ESCs and iPSCs are similar at the pluripotent stage, differences in mitochondrial function may develop during differentiation and must be taken into account when extrapolating results from different cell types.Abbreviation: BSA: Bovine serum albumin; DCFDA: 2',7'-dichlorodihydrofluorescein diacetate; DCX: Doublecortin; EAAT-1: Excitatory amino acid transporter 1; ESCs: Embryonic stem cells; GFAP: Glial fibrillary acidic protein; GS: Glutamine synthetase; iPSCs: Induced pluripotent stem cells; LC3B: Microtubule-associated protein 1 light chain 3β; LC-MS: Liquid chromatography-mass spectrometry; mito-ROS: Mitochondrial ROS; MMP: Mitochondrial membrane potential; MRC: Mitochondrial respiratory chain; mtDNA: Mitochondrial DNA; MTDR: MitoTracker Deep Red; MTG: MitoTracker Green; NSCs: Neural stem cells; PDL: Poly-D-lysine; PFA: Paraformaldehyde; PGC-1α: PPAR-γ coactivator-1 alpha; PPAR-γ: Peroxisome proliferator-activated receptor-gamma; p-SIRT1: Phosphorylated sirtuin 1; p-ULK1: Phosphorylated unc-51 like autophagy activating kinase 1; qPCR: Quantitative PCR; RT: Room temperature; RT-qPCR: Quantitative reverse transcription PCR; SEM: Standard error of the mean; TFAM: Mitochondrial transcription factor A; TMRE: Tetramethylrhodamine ethyl ester; TOMM20: Translocase of outer mitochondrial membrane 20.