Chromosomal instability and its effect on cell lines

α-Fodrin-CENP-E interaction is critical for pancreatic cancer progression and drug response

α-Fodrin, a known scaffolding protein for cytoskeleton stabilization, performs various functions including cell adhesion, cell motility, DNA repair and apoptosis. Based on our previous results revealing its role in mitosis in glioblastoma, we have examined its effect in pancreatic cancer, which is often linked to mitotic aberrations including aneuploidy and chromosome instability. Here, we show that the expression of α-Fodrin increases in pancreatic adenocarcinoma tissues compared to its normal counterpart, suggesting its tumor promoting role. shRNA-mediated knock-down of α-Fodrin significantly reduces the xenograft growth in immunocompromised mice underscoring the importance of α-Fodrin in tumor progression. CENP-E (centromere-associated protein E) is a motor protein essential for chromosomal alignment and segregation during mitosis. We have found that α-Fodrin interacts with CENP-E to recruit it to the kinetochore and depletion of α-Fodrin has a crucial role in controlling aneuploidy. As these mitotic defects can lead to apoptosis, we have further evaluated the activation of possible upstream pathways. Paclitaxel, a chemotherapeutic agent that stabilizes microtubules, disrupts mitosis and induces apoptosis. We found that Paclitaxel triggered stronger activation of JNK, ERK, and P38 MAPKs, altered BCL2/BAX ratios, cytochrome C release causing increased apoptosis in α-Fodrin knockdown cells compared to cells with wild-type α-Fodrin. This enhanced sensitivity to paclitaxel is consistent with improved survival in pancreatic cancer patients with low α-Fodrin (SPTAN1) and low CENP-E expression compared to poor prognosis with high expressions of both the genes. Taken together, this study provides the molecular mechanism by which α-Fodrin - CENP-E axis regulates pancreatic cancer progression and drug response.

Optimized toolkit for the manipulation of immortalized axolotl fibroblasts

The axolotl salamander model has broad utility for regeneration studies, but this model is limited by a lack of efficient cell-culture-based tools. The Axolotl Limb-1 (AL-1) fibroblast line, the only available immortalized axolotl cell line, was first published over 20 years ago, but many established molecular biology techniques, such as lipofectamine transfection, CRISPR-Cas9 mutagenesis, and antibiotic selection, work poorly or remain untested in AL-1 cells. Innovating technologies to manipulate AL-1 cells in culture and study their behavior following transplantation into the axolotl will complement in-vivo studies, decrease the number of animals used, and enable the faster, more streamlined investigation of regenerative biology questions. Here, we establish transfection, mutagenesis, antibiotic selection, and in-vivo transplantation techniques in axolotl AL-1 cells. These techniques will enable efficient culture with AL-1 cells and guide future tool development for the culture and manipulation of other salamander cell lines.

Opportunities of patient-derived organoids in drug development

Various model systems are utilised during drug development starting from basic research, moving to preclinical research and development for clinical applications in order to identify new drugs to improve human health. However, there are characteristics of humans that are not captured by established models. Such models include homogeneous two-dimensional (2D) cell lines, which lack cellular heterogeneity and physiological relevance, and species differences of animal models. Organoids can mitigate these differences by providing more physiologically relevant three-dimensional (3D) cell models that resemble the molecular state in healthy and pathological tissue. This review presents exemplary approaches using patient-derived organoids (PDOs) that have been developed and the new opportunities that are evolving in drug development with a focus on patient adult stem cell (ASC)-derived organoids. These demonstrate the potential of PDOs used alongside established cell and animal models to improve drug development from basic research to clinical applications such as personalised medicine.

PICH, A protein that maintains genomic stability, can promote tumor growth

Genomic instability is regardedas a hallmark of cancer cells. It can be presented in many ways, among which chromosome instability has received attention. Ultrafine anaphase bridges are a typeof chromatin bridges, the untimely resolution of which can also lead to chromosome instability. PICH can play a role in maintaining chromosome stability by regulating chromosome morphologyand resolving ultrafine anaphase bridges. Recently, PICH has been found to be overexpressed in various cancers. Overexpression of PICH is related to the proliferation of tumors and poor prognosis. In this article, we consider that PICH can maintain genomic stability by regulating appropriate chromosome structure, ensuring proper chromosome segregation, and facilitating replication fork reversal. We summarize how PICH regulates chromosome stability, how PICH resolves Ultrafine anaphase bridges with other proteins, and how PICH promotes tumor progression.

Cultivated meat microbiological safety considerations and practices

Cultivated meat, produced using cell culture technology, is an alternative to conventional meat production that avoids the risks from enteric pathogens associated with animal slaughter and processing. Cultivated meat therefore has significant theoretical microbiological safety advantages, though limited information is available to validate this. This review discusses sources and vectors of microbial contamination throughout cultivated meat production, introduces industry survey data to evaluate current industry practices for monitoring and mitigating these hazards, and highlights future research needs. Industry survey respondents reported an average microbiological contamination batch failure rate of 11.2%. The most common vectors were related to personnel, equipment, and the production environment, while the most commonly reported type of microbiological contaminant was bacteria. These will likely remain prominent vectors and source organisms in commercial-scale production but can be addressed by a modified combination of existing commercial food and biopharmaceutical production safety systems such as Hazard Analysis and Critical Control Points (HACCP), Good Manufacturing Practices (GMP), and Good Cell Culture Practice (GCCP). As the sector matures and embeds these and other safety management systems, microbiological contamination issues should be surmountable. Data are also included to investigate whether the limited microbiome of cultivated products poses a novel food safety risk. However, further studies are needed to assess the growth potential of microorganisms in different cultivated meat products, taking into account factors such as their composition, pH, water activity, and background microflora.

Genetic Characteristics of the Rat Fibroblast Cell Line Rat-1

The Rat-1 cell line was established as a subclone of the parental rat fibroblastoid line F2408, derived from Fisher 344 rat embryos. Rat-1 cells are widely used in various research fields, especially in cancer biology, to study the effects of oncogenes on cell proliferation. They are also crucial for investigating signal transduction pathways and play a key role in drug testing and pharmacological studies due to their rapid proliferation. Therefore, Rat-1 cells are an indispensable research tool. While some cytogenetic information on their basic chromosomal features is available, detailed genomic analyses, such as karyotype analysis, short tandem repeat (STR) profiling, and whole-genome sequencing, have not been thoroughly conducted. As a result, the genetic stability and potential variations in Rat-1 cells over extended culture periods are poorly understood. This lack of comprehensive genetic characterization can limit the interpretation of experimental results and requires caution when generalizing findings from studies using this cell line. In this study, we describe the genetic characterization of the Rat-1 cell line. We established a karyotype, performed multicolor fluorescence in situ hybridization (mFISH), identified chromosomal losses and gains, and defined an STR profile for Rat-1 with 31 species-specific markers. Interestingly, the chromosomal imbalances found in Rat-1 cells resemble those found in human epithelioid sarcoma or liposarcoma. Additionally, we analyzed the transcriptome of Rat-1 cells through mRNA sequencing (mRNA-Seq) using next-generation sequencing (NGS). Finally, typical features of these fibroblastic cells were determined using electron microscopy, Western blotting, and fluorescent phalloidin conjugates.

Macrophage variants in laboratory research: most are well done, but some are RAW

Macrophages play a pivotal role in the innate immune response. While their most characteristic function is phagocytosis, it is important not to solely characterize macrophages by this activity. Their crucial roles in body development, homeostasis, repair, and immune responses against pathogens necessitate a broader understanding. Macrophages exhibit remarkable plasticity, allowing them to modify their functional characteristics in response to the tissue microenvironment (tissue type, presence of pathogens or inflammation, and specific signals from neighboring cells) swiftly. While there is no single defined "macrophage" entity, there is a diverse array of macrophage types because macrophage ontogeny involves the differentiation of progenitor cells into tissue-resident macrophages, as well as the recruitment and differentiation of circulating monocytes in response to tissue-specific cues. In addition, macrophages continuously sense and respond to environmental cues and tissue conditions, adjusting their functional and metabolic states accordingly. Consequently, it is of paramount importance to comprehend the heterogeneous origins and functions of macrophages employed in in vitro studies, as each available in vitro macrophage model is associated with specific sets of strengths and limitations. This review centers its attention on a comprehensive comparison between immortalized mouse macrophage cell lines and primary mouse macrophages. It provides a detailed analysis of the strengths and weaknesses inherent in these in vitro models. Finally, it explores the subtle distinctions between diverse macrophage cell lines, offering insights into numerous factors beyond the model type that can profoundly influence macrophage function.

Chromosomal instability: a key driver in glioma pathogenesis and progression

Chromosomal instability (CIN) is a pivotal factor in gliomas, contributing to their complexity, progression, and therapeutic challenges. CIN, characterized by frequent genomic alterations during mitosis, leads to genetic abnormalities and impacts cellular functions. This instability results from various factors, including replication errors and toxic compounds. While CIN's role is well documented in cancers like ovarian cancer, its implications for gliomas are increasingly recognized. CIN influences glioma progression by affecting key oncological pathways, such as tumor suppressor genes (e.g., TP53), oncogenes (e.g., EGFR), and DNA repair mechanisms. It drives tumor evolution, promotes inflammatory signaling, and affects immune interactions, potentially leading to poor clinical outcomes and treatment resistance. This review examines CIN's impact on gliomas through a narrative approach, analyzing data from PubMed/Medline, EMBASE, the Cochrane Library, and Scopus. It highlights CIN's role across glioma subtypes, from adult glioblastomas and astrocytomas to pediatric oligodendrogliomas and astrocytomas. Key findings include CIN's effect on tumor heterogeneity and its potential as a biomarker for early detection and monitoring. Emerging therapies targeting CIN, such as those modulating tumor mutation burden and DNA damage response pathways, show promise but face challenges. The review underscores the need for integrated therapeutic strategies and improved bioinformatics tools like CINdex to advance understanding and treatment of gliomas. Future research should focus on combining CIN-targeted therapies with immune modulation and personalized medicine to enhance patient outcomes.

From Pluripotent Stem Cells to Organoids and Bioprinting: Recent Advances in Dental Epithelium and Ameloblast Models to Study Tooth Biology and Regeneration

Ameloblasts are the specialized dental epithelial cell type responsible for enamel formation. Following completion of enamel development in humans, ameloblasts are lost and biological repair or regeneration of enamel is not possible. In the past, in vitro models to study dental epithelium and ameloblast biology were limited to freshly isolated primary cells or immortalized cell lines, both with limited translational potential. In recent years, large strides have been made with the development of induced pluripotent stem cell and organoid models of this essential dental lineage - both enabling modeling of human dental epithelium. Upon induction with several different signaling factors (such as transforming growth factor and bone morphogenetic proteins) these models display elevated expression of ameloblast markers and enamel matrix proteins. The advent of 3D bioprinting, and its potential combination with these advanced cellular tools, is poised to revolutionize the field - and its potential for tissue engineering, regenerative and personalized medicine. As the advancements in these technologies are rapidly evolving, we evaluate the current state-of-the-art regarding in vitro cell culture models of dental epithelium and ameloblast lineage with a particular focus toward their applicability for translational tissue engineering and regenerative/personalized medicine.

An integrated toolkit for human microglia functional genomics

BACKGROUND

Microglia, the brain's resident immune cells, play vital roles in brain development, and disorders like Alzheimer's disease (AD). Human iPSC-derived microglia (iMG) provide a promising model to study these processes. However, existing iMG generation protocols face challenges, such as prolonged differentiation time, lack of detailed characterization, and limited gene function investigation via CRISPR-Cas9.

METHODS

Our integrated toolkit for in-vitro microglia functional genomics optimizes iPSC differentiation into iMG through a streamlined two-step, 20-day process, producing iMG with a normal karyotype. We confirmed the iMG's authenticity and quality through single-cell RNA sequencing, chromatin accessibility profiles (ATAC-Seq), proteomics and functional tests. The toolkit also incorporates a drug-dependent CRISPR-ON/OFF system for temporally controlled gene expression. Further, we facilitate the use of multi-omic data by providing online searchable platform that compares new iMG profiles to human primary microglia: https://sherlab.shinyapps.io/IPSC-derived-Microglia/ .

RESULTS

Our method generates iMG that closely align with human primary microglia in terms of transcriptomic, proteomic, and chromatin accessibility profiles. Functionally, these iMG exhibit Ca2 + transients, cytokine driven migration, immune responses to inflammatory signals, and active phagocytosis of CNS related substrates including synaptosomes, amyloid beta and myelin. Significantly, the toolkit facilitates repeated iMG harvesting, essential for large-scale experiments like CRISPR-Cas9 screens. The standalone ATAC-Seq profiles of our iMG closely resemble primary microglia, positioning them as ideal tools to study AD-associated single nucleotide variants (SNV) especially in the genome regulatory regions.

CONCLUSIONS

Our advanced two-step protocol rapidly and efficiently produces authentic iMG. With features like the CRISPR-ON/OFF system and a comprehensive multi-omic data platform, our toolkit equips researchers for robust microglial functional genomic studies. By facilitating detailed SNV investigation and offering a sustainable cell harvest mechanism, the toolkit heralds significant progress in neurodegenerative disease drug research and therapeutic advancement.

Preclinical Models of Neuroblastoma-Current Status and Perspectives

Preclinical in vitro and in vivo models remain indispensable tools in cancer research. These classic models, including two- and three-dimensional cell culture techniques and animal models, are crucial for basic and translational studies. However, each model has its own limitations and typically does not fully recapitulate the course of the human disease. Therefore, there is an urgent need for the development of novel, advanced systems that can allow for efficient evaluation of the mechanisms underlying cancer development and progression, more accurately reflect the disease pathophysiology and complexity, and effectively inform therapeutic decisions for patients. Preclinical models are especially important for rare cancers, such as neuroblastoma, where the availability of patient-derived specimens that could be used for potential therapy evaluation and screening is limited. Neuroblastoma modeling is further complicated by the disease heterogeneity. In this review, we present the current status of preclinical models for neuroblastoma research, discuss their development and characteristics emphasizing strengths and limitations, and describe the necessity of the development of novel, more advanced and clinically relevant approaches.