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To study telomere maintenance mechanism (TMM) activation during malignant transformation, we compared neurofibroma (NF) and malignant peripheral nerve sheath tumor (MPNST) in the same patient with type-1 neurofibromatosis (NF1), a total of 20 NF-MPNST pairs in 20 NF1 patients. These comparisons minimized genetic bias and contrasted only changes associated with malignant transformation, while subtracting changes that developed upon the transformation of normal cells to the benign tumor. TGF-β superfamily genes were found to activate the PAX and SOX transcription factors, leading to TMM activation. BMPER activates PAX6 through BMP2 and PAX7 through BMP4; BMP15 activates SOX14; and INHBC activates PAX9 and SOX14. The activated PAX and SOX genes sequentially establish the core architecture of the RAD52-dependent alternative lengthening of telomeres (ALT). Specifically, PAX7 activates the recombinase (RAD52) and a negative regulator (SLX4IP). PAX6 and SOX14 activate positive regulators (BLM and BRCA2, respectively). PAX9 and SOX14 activate RAD9B and FEN1, which are responsible for the stability of homologous recombination intermediates and increase, together with RAD52, the telomere length. Telomere elongation achieved by the activation of PAX7 and PAX9 is associated with a poor prognosis. We demonstrated that TGF-β superfamily-induced transcriptional activation pathways activated the RAD52-dependent ALT during malignant transformation of MPNSTs., (© 2024. The Author(s).)

The development of myeloid malignancies is influenced by a range of cell-intrinsic and cell-extrinsic factors, which can be conceptualized using the hallmarks of cancer. Although many facets of myeloid transformation are similar to those in solid tumors, there are also notable differences. Unlike solid tumors, hematologic malignancies typically exhibit fewer genetic mutations, which have been well characterized. However, understanding the cell-extrinsic factors contributing to myeloid malignancies can be challenging due to the complex interactions in the hematopoietic microenvironment. Researchers need to focus on these intricate factors to prevent the early onset of myeloid transformation and develop appropriate interventions. Significance: Myeloid malignancies are common in the elderly, and acute myeloid leukemia has an adverse prognosis in older patients. Investigating cell-extrinsic factors influencing myeloid malignancies is crucial to developing approaches for preventing or halting disease progression and predicting clinical outcomes in patients with advanced disease. Whereas successful intervention may require targeting various mechanisms, understanding the contribution of each cell-extrinsic factor will help prioritize clinical targets., (©2024 American Association for Cancer Research.)

Aberrant expression of cyclin-dependent kinase 5 (Cdk5) has been reported in pituitary adenomas. However, the role of Cdk5 in the tumorigenesis remains unclear. We show that prenatal p25-activated Cdk5 phosphorylates minichromosome maintenance protein 2 (Mcm2), enhancing minichromosome maintenance (MCM) family proteins and driving intermediate lobe-located melanotrope-originated pituitary tumorigenesis. In a mouse model with CaMKII promoter-driven transgenic induction of p25, we observed intermediate lobe-originated pituitary adenoma producing non-functional proopiomelanocortin (POMC)-derived peptides under persistent p25 overexpression. Single-cell RNA sequencing revealed Mcm2 may play an important role during tumor progression. Subsequently, Mcm2 was identified as a potential phosphorylated substrate of Cdk5, mediating the tumorous proliferation of melanotrope cells. Silencing Cdk5 or Mcm2 suppressed cell proliferation and colony formation in the 293T cell lines. Therefore, our findings provide a new mouse model of intermediate lobe-originated pituitary adenoma induced by p25/Cdk5 and unveil a previously unappreciated role of Cdk5 and Mcm2 in pituitary adenoma tumorigenesis., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024. Published by Elsevier Inc.)

Background: Colorectal cancer (CRC) is still a leading cause of cancer deaths worldwide. Thus, identifying the aberrant genes and proteins underlying disease pathogenesis is critical to improve early detection methods and develop novel therapeutic strategies. Chromosome instability (CIN), or ongoing changes in chromosome complements, is a predominant form of genome instability. It is a driver of genetic heterogeneity found in ~85% of CRCs. Although CIN contributes to CRC pathogenesis, the molecular determinants underlying CIN remain poorly understood. Recently, EMI1, an F-box protein, was identified as a candidate CIN gene. In this study, we sought to determine the impact reduced EMI1 expression has on CIN and cellular transformation., Methods: Coupling siRNA-based silencing and CRISPR/Cas9 knockout clones with quantitative imaging microscopy we evaluated the impact reduced EMI1 expression has on CIN and cellular transformation in four colonic epithelial cell contexts., Results: Quantitative imaging microscopy data revealed that reduced EMI1 expression induces increases in CIN phenotypes in both transient (siRNA) and constitutive (CRISPR/Cas9) cell models that are associated with increases in DNA damage and cellular transformation phenotypes in long-term studies., Conclusions: This study determined that reduced EMI1 expression induces CIN and promotes cellular transformation, which is consistent with a role in early CRC development., (© 2024. The Author(s).)

Primary hyperparathyroidism represents the third most prevalent endocrine disease in the general population, consisting of an excessive secretion of parathyroid hormone from one or, more frequently, more of the parathyroid glands, leading to a dysregulation of calcium homeostasis. Schematically, its development occurs primarily by pathophysiological events with genetic mutation, at the germline and/or somatic level, that favor the neoplastic transformation of parathyroid cells and promote their aberrant proliferation, and mutations determining the shift in the PTH "set-point", thus interfering with the normal pathways of PTH secretion and leading to a "resetting" of Ca 2+ -dependent PTH secretion or to a secretion of PTH insensitive to changes in extracellular Ca 2+ levels. Familial syndromic and non-syndromic forms of primary hyperparathyroidism are responsible for approximately 2-5% of primary hyperparathyroidism cases and most of them are inherited forms. The history of the genetic/molecular studies of parathyroid tumorigenesis associated with multiple endocrine neoplasia type 1 syndrome (MEN1) represents an interesting model to understand genetic-epigenetic-molecular aspects underlying the pathophysiology of primary hyperparathyroidism, both in relation to syndromic and non-syndromic forms. This minireview aims to take a quick and simplified look at the MEN1-associated parathyroid tumorigenesis, focusing on the molecular underlying mechanisms. Clinical, epidemiological, and observational studies, as well as specific guidelines, molecular genetics studies, and reviews, have been considered. Only studies submitted to PubMed in the English language were included, without time constraints.

Follicular lymphoma (FL) is the most prevalent indolent B-cell lymphoma entity, often characterized by the t(14;18) BCL2-IGH translocation. The malignancy represents a clinically and biologically highly heterogeneous disease. Most patients have favorable prognoses; however, despite therapeutic advancements, the disease remains incurable, with recurrent relapses or early disease progression. Moreover, transformation to an aggressive histology, most often diffuse large-B-cell lymphoma, remains a critical event in the disease course, which is associated with poor outcomes. Understanding the individual patient's risk of transformation remains challenging, which has motivated much research on novel biomarkers within the past four decades. This review systematically assessed the research on molecular biomarkers in FL transformation and outcome. Following the PRISMA guidelines for systemic reviews, the PubMed database was searched for English articles published from January 1984 through September 2024, yielding 6769 results. The identified publications were carefully screened and reviewed, of which 283 original papers met the inclusion criteria. The included studies focused on investigating molecular biomarkers as predictors of transformation or as prognostic markers of time-related endpoints (survival, progression, etc.). The effects of each biomarker were categorized based on their impact on prognosis or risk of transformation as none, favorable, or inferior. The biomarkers included genetic abnormalities, gene expression, microRNAs, markers of B cells/FL tumor cells, markers of the tumor microenvironment, and soluble biomarkers. This comprehensive review provides an overview of the research conducted in the past four decades, underscoring the persistent challenge in risk anticipation of FL patients.

Nontransformed cells form heterotypic cadherin junctions with adjacent transformed cells to inhibit tumor cell growth and motility. Transformed cells must override this form of growth control, called "contact normalization", to invade and metastasize during cancer progression. Heterocellular cadherin junctions between transformed and nontransformed cells are needed for this process. However, specific mechanisms downstream of cadherin signaling have not been clearly elucidated. Here, we utilized a β-catenin reporter construct to determine if contact normalization affects Wnt signaling in transformed cells. β-catenin driven GFP expression in Src transformed mouse embryonic cells was decreased when cultured with cadherin competent nontransformed cells compared to transformed cells cultured with themselves, but not when cultured with cadherin deficient nontransformed cells. We also utilized a layered culture system to investigate the effects of oncogenic transformation and contact normalization on gene expression and oncogenic Src kinase mediated phosphorylation events. RNA-Seq analysis found that cadherin dependent contact normalization inhibited the expression of 22 transcripts that were induced by Src transformation, and increased the expression of 78 transcripts that were suppressed by Src transformation. Phosphoproteomic analysis of cells expressing a temperature sensitive Src kinase construct found that contact normalization decreased phosphorylation of 10 proteins on tyrosine residues that were phosphorylated within 1 h of Src kinase activation in transformed cells. Taken together, these results indicate that cadherin dependent contact normalization inhibits Wnt signaling to regulate oncogenic kinase activity and gene expression, particularly PDPN expression, in transformed cells in order to control tumor progression., (© 2024. The Author(s).)

The mechanisms involved with the pathogenesis of carcinoma ex pleomorphic adenoma (CXPA) seem to be associated with the accumulation of molecular alterations in the pleomorphic adenoma (PA). In this sense, using array-based comparative genomic hybridization (aCGH) a rare series of 27 cases of CXPA and 14 residual PA (rPA) adjacent to the transformation area, we investigated the profile of the copy number alterations (CNAs) comparing benign residual and transformed areas. The main findings were correlated with the histopathological classification by histologic subtype and degree of invasion. The distribution of losses (p = 0.187) and amplifications (p = 0.172) was not statistically different between rPA and CXPA. The number of gains was increased in the transformed areas compared to the benign residual areas (p = 0.005). PLAG1 gain was maintained along the malignant transformation, as it was observed in both residual PA and CXPA samples, likely being an earlier event during transformation. The amplification of GRB7 and ERBB2 may also be an initial step in the malignant transformation of PA to CXPA (salivary duct carcinoma subtype). Furthermore, the amplification of HMGA2 and RPSAP52 were the most prevalent alterations among the studied samples. It was noteworthy that amplified genes in the transformed areas of the tumors were enriched for biological processes related to immune signaling. In conclusion, our results underscored for the first-time crucial CNAs in CXPA, some of them shared with the residual benign area adjacent to the transformation site. These CNAs included PLAG1 gain, as well as amplification of GRB7, ERBB2, HMGA2, and RPSAP52., (© 2024. The Author(s).)

Small-cell lung cancer (SCLC) transformation accounts for 3-14% of resistance in EGFR-TKI relapsed lung adenocarcinomas (LUADs), with unknown molecular mechanisms and optimal treatment strategies. We performed transcriptomic analyses (including bulk and spatial transcriptomics) and multiplex immunofluorescence on pre-treated samples from LUADs without transformation after EGFR-TKI treatment (LUAD-NT), primary SCLCs (SCLC-P) and LUADs with transformation after EGFR-TKI treatment (before transformation: LUAD-BT; after transformation: SCLC-AT). Our study found that LUAD-BT exhibited potential transcriptomic characteristics for transformation compared with LUAD-NT. We identified several pathways that shifted during transformation, and the transformation might be promoted by epigenetic alterations (such as HDAC10, HDAC1, DNMT3A) within the tumor cells instead of within the tumor microenvironment. For druggable pathways, transformed-SCLC were proved to be less dependent on EGF signaling but more relied on FGF signaling, while VEGF-VEGFR pathway remained active, indicating potential treatments after transformation. We also found transformed-SCLC showed an immuno-exhausted status which was associated with the duration of EGFR-TKI before transformation. Besides, SCLC-AT exhibited distinct molecular subtypes from SCLC-P. Moreover, we constructed an ideal 4-marker model based on transcriptomic and IHC data to predict SCLC transformation, which obtained a sensitivity of 100% and 87.5%, a specificity of 95.7% and 100% in the training and test cohorts, respectively. We provided insights into the molecular mechanisms of SCLC transformation and the differences between SCLC-AT and SCLC-P, which might shed light on prevention strategies and subsequent therapeutic strategies for SCLC transformation in the future., (© 2024. The Author(s).)

Loss-of-function mutations in the tumour suppressor APC are an initial step in intestinal tumorigenesis 1,2 . APC-mutant intestinal stem cells outcompete their wild-type neighbours through the secretion of Wnt antagonists, which accelerates the fixation and subsequent rapid clonal expansion of mutants 3-5 . Reports of polyclonal intestinal tumours in human patients and mouse models appear at odds with this process 6,7 . Here we combine multicolour lineage tracing with chemical mutagenesis in mice to show that a large proportion of intestinal tumours have a multiancestral origin. Polyclonal tumours retain a structure comprising subclones with distinct Apc mutations and transcriptional states, driven predominantly by differences in KRAS and MYC signalling. These pathway-level changes are accompanied by profound differences in cancer stem cell phenotypes. Of note, these findings are confirmed by introducing an oncogenic Kras mutation that results in predominantly monoclonal tumour formation. Further, polyclonal tumours have accelerated growth dynamics, suggesting a link between polyclonality and tumour progression. Together, these findings demonstrate the role of interclonal interactions in promoting tumorigenesis through non-cell autonomous pathways that are dependent on the differential activation of oncogenic pathways between clones., (© 2024. The Author(s).)

Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) play fundamental roles in stem/progenitor cell expansion during homeostasis, and their dysregulation often leads to tissue overgrowth. Here, we show that YAP activation is sufficient to overcome the restriction of global protein synthesis induced by serum starvation, enabling cells to sustain proliferation and survival despite an unfavorable environment. Mechanistically, YAP/TAZ selectively promoted the mTORC1-dependent translation of mRNAs containing 5' terminal oligopyrimidine (5'TOP) motifs, ultimately increasing the cellular polysome content. Interestingly, DNA damage-inducible transcript 4 (DDIT4), a negative regulator of mTORC1, was upregulated by serum starvation but repressed by YAP/TAZ. DDIT4 was sufficient to suppress the translation and transformative potential of uveal melanoma cells, which are often serum unresponsive due to G protein mutations. Our findings reveal a vital role for protein synthesis as a key modality of YAP/TAZ-induced oncogenic transformation and indicate the potential for targeting mTORC1 or translation to treat YAP/TAZ-driven malignancies., (© 2024. The Author(s).)

Our current understanding of epigenetic regulation is deeply rooted in the founding contributions of Dr C. David Allis. In 2002, Allis and colleagues first characterized the lysine methyltransferase activity of the mammalian KMT2A (MLL1), a paradigm-shifting discovery that brings epigenetic dysregulation into focus for many human diseases that carry KMT2A mutations. This review will discuss the current understanding of the multifaceted roles of KMT2A in development and disease, which has paved the way for innovative and upcoming approaches to cancer therapy., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

High grade serous ovarian carcinoma (HGSOC) is the most common and aggressive ovarian malignancy. Accumulating evidence indicates that HGSOC may originate from human fallopian tube epithelial cells (FTECs), although the exact pathogen(s) and/or molecular mechanism underlying the malignant transformation of FTECs is unclear. Here we show that human papillomavirus (HPV), which could reach FTECs via retrograde menstruation or sperm-carrying, interacts with the yes-associated protein 1 (YAP1) to drive the malignant transformation of FTECs. HPV prevents FTECs from natural replicative and YAP1-induced senescence, thereby promoting YAP1-induced malignant transformation of FTECs. HPV also stimulates proliferation and drives metastasis of YAP1-transformed FTECs. YAP1, in turn, stimulates the expression of the putative HPV receptors and suppresses the innate immune system to facilitate HPV acquisition. These findings provide critical clues for developing new strategies to prevent and treat HGSOC., (© 2024. The Author(s).)

Small extracellular vesicles (sEV) transfer cargos between cells and participate in various physiological and pathological processes through their autocrine and paracrine effects. However, the pathological mechanisms employed by sEV-encapsulated microRNA (miRNA) in acute myeloid leukemia (AML) are still obscure. In this study, we aimed to investigate the effects of AML cell-derived sEV (AML-sEV) on AML cells and delineate the underlying mechanisms. We initially used high-throughput sequencing to identify miR-221-3p as the miRNA prominently enriched in AML-sEV. Our findings revealed that miR-221-3p promoted AML cell proliferation and leukemogenesis by accelerating cell cycle entry and inhibiting apoptosis. Furthermore, Gbp2 was confirmed as a target gene of miR-221-3p by dual luciferase reporter assays and rescue experiments. Additionally, AML-sEV impaired the clonogenicity, particularly the erythroid differentiation ability, of hematopoietic stem and progenitor cells. Taken together, our findings reveal how sEV-delivered miRNA contribute to AML pathogenesis, which can be exploited as a potential therapeutic target to attenuate AML progression.

N-Methyl-N'-nitro-N-nitrosoguanidine (MNNG) and Helicobacter pylori might synergistically promote the malignant transformation of human esophageal epithelial cells (HEECs) through inducing DNA double-strand breaks (DSBs) and inhibition of PAXX protein expression. The long noncoding RNA (lncRNA) TUG1 is associated with multiple cancers, and its overexpression can promote cancer by interfering with the functions of oncogenes. LncRNA TUG1 is also associated with DNA methyltransferase 1 (DNMT1) and the epithelial signaling pathway of H. pylori infection. To explore the role of LncRNA TUG1 in the malignant transformation of HEECs induced by H.pylori + MNNG, a stable strain of HEECs with LncRNA TUG1 knockdown (LncRNA TUG1-KD) was constructed using RNA interference technology with lentivirus as a vector. Set up negative controls LncRNA TUG1-NC (null carrier lentivirus was selected to transfect HEECs) and block controls (normal HEECs without exposure). H. pylori + MNNG were added to the LncRNA TUG1-KD and LncRNA TUG1-NC groups for 6 h and then passaged until their malignant transformation. From each group, cells in the early, intermediate, and late stages of malignant transformation were used for the alkaline comet assay and determination of protein expression, including γ-H2AX and PAXX, by western blotting assay to assess DNA damage and repair processes. Clone formation assay in soft agar and nude mouse xenograft model was used to assess malignancy. This study suggests that H. pylori + MNNG promotes the malignant transformation of HEECs by inducing DNA DSBs and inhibiting PAXX expression, and this effect may be alleviated by LncRNA TUG1 knockdown. It elucidates the pathogenesis of EC from the perspective of the combined effect of epigenetic and environmental carcinogens, offering new insights for the comprehensive prevention and treatment of EC., Competing Interests: Declaration of competing interest The authors have declared that no conflict of interest exists., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background: Pancreatic ductal adenocarcinoma (PDAC) features KRAS mutations in approximately 90% of human cases and excessive stromal response, termed desmoplastic reaction. Oncogenic KRAS drives pancreatic carcinogenesis by acting on both epithelial cells and tumor microenvironment (TME). We have previously shown that Homeodomain-Interacting Protein Kinase 2 (HIPK2) cooperates with KRAS in sustaining ERK1/2 phosphorylation in human colorectal cancers. Here, we investigated whether HIPK2 contributes to oncogenic KRAS-driven tumorigenesis in vivo, in the onset of pancreatic cancer., Methods: We employed an extensively characterized model of KRAS G12D -dependent preinvasive PDAC, the Pdx1-Cre;LSL-KRas G12D/+ (KC) mice. In these mice, HIPK2 was inhibited by genetic knockout in the pancreatic epithelial cells (KCH -/- ) or by pharmacologic inactivation with the small molecule 5-IodoTubercidin (5-ITu). The development of preneoplastic acinar-to-ductal metaplasia (ADM), intraepithelial neoplasia (PanIN), and their associated desmoplastic reaction were analyzed., Results: In Hipk2-KO mice (KCH -/- ), ERK phosphorylation was lowered, the appearance of ADM was slowed down, and both the number and pathologic grade of PanIN were reduced compared to Hipk2-WT KC mice. The pancreatic lesion phenotype in KCH -/- mice was characterized by abundant collagen fibers and reduced number of αSMA + and pSTAT3 + desmoplastic cells. These features were reminiscent of the recently described human "deserted" sub-TME, poor in cells, rich in matrix, and associated with tumor differentiation. In contrast, the desmoplastic reaction of KC mice resembled the "reactive" sub-TME, rich in stromal cells and associated with tumor progression. These observations were confirmed by the pharmacologic inhibition of HIPK2 in KC mice., Conclusion: This study demonstrates that HIPK2 inhibition weakens oncogenic KRAS activity and pancreatic tumorigenesis providing a rationale for testing HIPK2 inhibitors to mitigate the incidence of PDAC development in high-risk individuals., (© 2024. The Author(s).)

The ROS1 receptor tyrosine kinase (RTK) possesses the largest extracellular amino-terminal domain (ECD) among the human RTK family, yet the mechanisms regulating its activation are not fully understood. While chimeric ROS1 fusion proteins, resulting from chromosomal rearrangements, are well-known oncogenic drivers, their activation mechanisms also remain underexplored. To elucidate the role of the ROS1 ECD in catalytic regulation, we engineered a series of amino-terminal deletion mutants. Our functional studies compared the full-length ROS1 receptor, the CD74-ROS1 oncogenic fusion, and ECD-deleted ROS1 constructs, identifying the ECD regions that inhibit ROS1 tyrosine kinase activity. Notably, we found that deletion of the ROS1 ECD alone significantly increases constitutive catalytic activation and neoplastic transformation in the absence of an amino-terminal fusion partner, challenging the presumed necessity for a dimerization domain in the activation mechanism of kinase fusions in cancer. Our data suggest that inter-genic deletions resulting in the loss of the ECD may be underappreciated oncogenic drivers in cancer. Furthermore, our studies demonstrate that RNASE7 is not a ligand for the ROS1 receptor as previously reported, confirming that ROS1 remains an orphan receptor. Thus, the discovery of a ROS1 ligand remains an important future priority. These findings highlight the potential for disease-associated somatic aberrations or splice variants that modify the ROS1 ECD to promote constitutive receptor activation, warranting further investigation., (© 2024. The Author(s).)

We previously showed that inhibition of glycolysis in cutaneous squamous cell carcinoma (SCC)-initiating cells had no effect on tumorigenesis, despite the perceived requirement of the Warburg effect, which was thought to drive carcinogenesis. Instead, these SCCs were metabolically flexible and sustained growth through glutaminolysis, another metabolic process frequently implicated to fuel tumorigenesis in various cancers. Here, we focused on glutaminolysis and genetically blocked this process through glutaminase (GLS) deletion in SCC cells of origin. Genetic deletion of GLS had little effect on tumorigenesis due to the up-regulated lactate consumption and utilization for the TCA cycle, providing further evidence of metabolic flexibility. We went on to show that posttranscriptional regulation of nutrient transporters appears to mediate metabolic flexibility in this SCC model. To define the limits of this flexibility, we genetically blocked both glycolysis and glutaminolysis simultaneously and found the abrogation of both of these carbon utilization pathways was enough to prevent both papilloma and frank carcinoma.

The intricate interplay of cancer stem cell plasticity, along with the bidirectional transformation between epithelial-mesenchymal states, introduces further intricacy to offer insights into newer therapeutic approaches. Differentiation therapy, while successful in targeting leukemic stem cells, has shown limited overall success, with only a few promising instances. Using colon carcinoma cell strains with sequential p53/p73 knockdowns, our study underscores the association between p53/p73 and the maintenance of cellular plasticity. Morphological alterations corresponding with cell surface marker expressions, transcriptome analysis and functional assays were performed to access stemness and EMT (Epithelial-Mesenchymal Transition) characteristics in the spectrum of cells exhibiting sequential p53 and p73 knockdowns. Notably, our investigation explores the effectiveness of esculetin in reversing the shift from an epithelial to a mesenchymal phenotype, characterized by stem cell-like traits. Esculetin significantly induces enterocyte differentiation and promotes epithelial cell polarity by altering Wnt axes in Cancer Stem Cell-like cells characterized by high mesenchymal features. These results align with our previous findings in leukemic blast cells, establishing esculetin as an effective differentiating agent in both Acute Myeloid Leukemia (AML) and solid tumor cells., (© 2024. The Author(s).)

Background: Oral squamous cell carcinoma (OSCC) is a prevalent and aggressive form of head and neck cancer, often diagnosed at advanced stages. Elucidating the molecular mechanisms involved in the malignant transformation from normal oral tissue to oral preinvasive lesions (OPL) and primary OSCC could facilitate early diagnosis and improve therapeutic strategies. Methods: Differentially expressed genes (DEGs) were identified from the GSE30784 dataset by comparing normal oral tissue, oral dysplasia, and primary OSCC samples. Cross-validation was performed using an independent RNA-seq dataset, GSE186775. Protein-protein interaction (PPI) network analysis, gene ontology annotation, and pathway enrichment analysis were conducted on the common DEGs. Hub genes were identified, and their prognostic significance was evaluated using survival analysis. Transcription factor (TF) enrichment analysis, cross-validation, and immunohistochemistry analyses were also performed. Results: A total of 226 proteins and 677 interactions were identified in the PPI network, with 34 hub genes, including FN1, SERPINE1, PLAUR, THBS1, and ITGA6. Pathways such as "Formation of the cornified envelope," "Keratinization," and "Developmental biology" were enriched. Overexpression of SERPINE1, PLAUR, THBS1, and ITGA6 correlated with poor prognosis, while upregulation of CALML5 and SPINK5 was associated with favorable outcomes. NFIB emerged as the most significant TF-regulating hub genes. Immunohistochemistry validated ITGA6 overexpression in primary OSCC. Cross-validation using the RNA-seq dataset supported the involvement of critical genes in the malignant transformation process. Conclusion: This study identified vital genes, pathways, and prognostic markers involved in the malignant transformation from normal oral tissue to OPL and primary OSCC, providing insights for early diagnosis and targeted therapy development. Cross-validation with an independent RNA-seq dataset and immunohistochemistry reinforced the findings, supporting the robustness of the identified molecular signatures., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 Shokoofeh Jamshidi et al.)

Arsenic is a widespread carcinogen and an important etiological factor for lung cancer. Dysregulated miRNAs have been implicated in arsenic carcinogenesis and the mechanisms of arsenic-induced dysregulated miRNAs have not been fully elucidated. N 6 -methyladenosine (m 6 A) modification is known to modulate pri-miRNA processing. However, whether m 6 A-mediated pri-miRNA processing is involved in arsenic carcinogenesis is poorly understood. Here, we found that m 6 A modification was significantly increased in arsenite-transformed human bronchial epithelial BEAS-2B cells (0.5 µM arsenite, 16 weeks). Meanwhile, METTL3 was significantly upregulated at week 12 and 16 during cell transformation. The proliferation, migration, invasion, and anchorage-independent growth of arsenite-transformed cells were inhibited by the reduction of m 6 A levels through METTL3 knockdown. Further experiments suggest that the oncogene miR-106b-5p is a potentially essential m 6 A target mediating arsenic-induced lung cancer. miR-106b-5p was observed to be upregulated after exposure to arsenite for 12 and 16 weeks, and the reduction of m 6 A levels caused by METTL3 knockdown inhibited miR-106b-5p maturation in arsenite-transformed cells. What's more, miR-106b-5p overexpression successfully rescued METTL3 knockdown-induced inhibition of the neoplastic phenotypes of transformed cells. Additionally, Basonuclin 2 (BNC2) was uncovered as a potential target of miR-106b-5p and downregulated by METTL3 via enhancing miR-106b-5p maturation. Additionally, the METTL3 inhibitor STM2457 suppressed neoplastic phenotypes of arsenite-transformed BEAS-2B cells by blocking pri-miR-106b methylation. These results demonstrate that m 6 A modification promotes the neoplastic phenotypes of arsenite-transformed BEAS-2B cells through METTL3/miR-106b-5p/BNC2 pathway, providing a new prospective for understanding arsenic carcinogenesis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Liver cancer, recognized as a significant global health issue, is increasingly correlated with Hepatitis B virus (HBV) infection, as evidenced by numerous scientific studies. This study aims to examine the correlation between HBV infection and the development of liver cancer, focusing on using RNA sequencing (RNA-seq) to detect HBV sequences and applying deep learning techniques to estimate the likelihood of oncogenic transformation in individuals with HBV. Our study utilized RNA-seq data and employed Pathseq software and sophisticated deep learning models, including a convolutional neural network (CNN), to analyze the prevalence of HBV sequences in the samples of patients with liver cancer. Our research successfully identified the prevalence of HBV sequences and demonstrated that the CNN model achieved an exceptional Area Under the Curve (AUC) of 0.998 in predicting cancerous transformations. We observed no viral synergism that enhanced the pathogenicity of HBV. A detailed analysis of sequences misclassified by the CNN model revealed that longer sequences were more conducive to accurate recognition. The findings from this study provide critical insights into the management and prognosis of patients infected with HBV, highlighting the potential of advanced analytical techniques in understanding the complex interactions between viral infections and cancer development.

Malignant transformation (MT) is commonly seen in IDH-mutant gliomas. There has been a growing research interest in revealing its underlying mechanisms and intervening prior to MT at the early stages of the transforming process. Here we established a unique pair of matched 3D cell models: 403L, derived from a low-grade glioma (LGG), and 403H, derived from a high-grade glioma (HGG), by utilizing IDH-mutant astrocytoma samples from the same patient when the tumor was diagnosed as WHO grade 2 (tumor mutational burden (TMB) of 3.96/Mb) and later as grade 4 (TMB of 70.07/Mb), respectively. Both cell models were authenticated to a patient's sample retaining endogenous expression of IDH1 R132H. DNA methylation profiles of the parental tumors referred to LGG and HGG IDH-mutant glioma clusters. The immunopositivity of SOX2, NESTIN, GFAP, OLIG2, and beta 3-Tubulin suggested the multilineage potential of both models. 403H was more prompt to cell invasion and developed infiltrative HGG in vivo. The differentially expressed genes (DEGs) from the RNA sequencing analysis revealed the tumor invasion and aggressiveness related genes exclusively upregulated in the 403H model. Pathway analysis showcased an enrichment of genes associated with epithelial-mesenchymal transition (EMT) and Notch signaling pathways in 403H and 403L, respectively. Mass spectrometry-based targeted metabolomics and hyperpolarized (HP) 1- 13 C pyruvate in-cell NMR analyses demonstrated significant alterations in the TCA cycle and fatty acid metabolism. Citrate, glutamine, and 2-HG levels were significantly higher in 403H. To our knowledge, this is the first report describing the development of a matched pair of 3D patient-derived cell models representative of MT and temozolomide (TMZ)-induced hypermutator phenotype (HMP) in IDH-mutant glioma, providing insights into genetic and metabolic changes during MT/HMP. This novel in vitro model allows further investigation of the mechanisms of MT at the cellular level., (© 2024. This is a U.S. Government work and not under copyright protection in the US; foreign copyright protection may apply.)

Normal cells coordinate proliferation and differentiation by precise tuning of gene expression based on the dynamic shifts of the epigenome throughout the developmental timeline. Although non-mutational epigenetic reprogramming is an emerging hallmark of cancer, the epigenomic shifts that occur during the transition from normal to malignant cells remain elusive. Here, we capture the epigenomic changes that occur during tumorigenesis in a prototypic embryonal brain tumor, medulloblastoma. By comparing the epigenomes of the different stages of transforming cells in mice, we identify nuclear factor I family of transcription factors, known to be cell fate determinants in development, as oncogenic regulators in the epigenomes of precancerous and cancerous cells. Furthermore, genetic and pharmacological inhibition of NFIB validated a crucial role of this transcription factor by disrupting the cancer epigenome in medulloblastoma. Thus, this study exemplifies how epigenomic changes contribute to tumorigenesis via non-mutational mechanisms involving developmental transcription factors., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Cancer initiation has long been "unknowable" in biology and medicine. In 1987, however, Moore and our research group observed single hepatocytes and minifoci that were strongly positive for glutathione S-transferase P-form (GST-P) in the rat liver as early as 2 to 3 days after initiation by diethylnitrosamine prior to the induction of GST-P + foci and nodules. The induction of GST-P + single hepatocytes, precursors of GST-P + foci and nodules, was considered genetic. But, the details of the induction mechanism have remained unclear despite various examinations over a long period., Methods: Male Sprague-Dawley rats (aged 6 weeks) were fed a basal diet containing either benzyl isothiocyanate (BITC, 0.5% by wt) or 2-acetylaminofluorene (AAF, 0.04%) ad libitum for appropriate time intervals. All animals were anesthetized and euthanized. The livers obtained were excised, cut into 3- to 4-mm-thick slices and fixed in cold acetone at 4 °C. The liver specimens were then sliced into 25-µm-thick sections in PBS using an automated microtome (Vibratome 1500 Sectioning System, Vibratome Products, NY, USA). Immunocytochemical staining was performed in free solution, and the results were examined via digital light microscopy (Coolscope, Nikon, Tokyo)., Results: 3D analysis using a vibratome showed that GST-P is rapidly excreted into the bile of the liver of animals in response to strong carcinogenic stress caused by promoters or initiators. "Rapid biliary excretion of GST-P" was widely and commonly observed in all hepatocytes, GST-P + single hepatocytes, minifoci, foci and nodules under appropriate conditions. Surprisingly, on the basis of these key findings, a new mechanism of cancer initiation involving the transformation of hepatocytes into GST-P + single hepatocytes and minifoci in animal livers was identified. In addition, the initiation process was determined to be nongenetic because mutation is an invisible rare event., Conclusions: This short review describes several details about breakthrough findings on cancer initiation in rat livers, the application of 3D analysis to other cancers and the importance in the genetic analysis in malignant diseases., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Oncogenic mutations are abundant in the tissues of healthy individuals, but rarely form tumours 1-3 . Yet, the underlying protection mechanisms are largely unknown. To resolve these mechanisms in mouse mammary tissue, we use lineage tracing to map the fate of wild-type and Brca1 -/- ;Trp53 -/- cells, and find that both follow a similar pattern of loss and spread within ducts. Clonal analysis reveals that ducts consist of small repetitive units of self-renewing cells that give rise to short-lived descendants. This offers a first layer of protection as any descendants, including oncogenic mutant cells, are constantly lost, thereby limiting the spread of mutations to a single stem cell-descendant unit. Local tissue remodelling during consecutive oestrous cycles leads to the cooperative and stochastic loss and replacement of self-renewing cells. This process provides a second layer of protection, leading to the elimination of most mutant clones while enabling the minority that by chance survive to expand beyond the stem cell-descendant unit. This leads to fields of mutant cells spanning large parts of the epithelial network, predisposing it for transformation. Eventually, clone expansion becomes restrained by the geometry of the ducts, providing a third layer of protection. Together, these mechanisms act to eliminate most cells that acquire somatic mutations at the expense of driving the accelerated expansion of a minority of cells, which can colonize large areas, leading to field cancerization., (© 2024. The Author(s).)

Multiple myeloma (MM) is the second most common hematological cancer all over the world. Long non-coding RNA (lncRNA) nuclear-enriched autosomal transcript-1 (NEAT1) have been reported to play important roles in the development and progression of multiple human malignancies like MM. However, the functional role and molecular mechanism of NEAT1 in MM progression still needs more support to identify potential targets of MM. In the present study, we focused on the clinical and biological significance of NEAT1 in MM. We demonstrated that NEAT1 was up-regulated in MM tissues and cell line. NEAT1 silencing significantly inhibited cell proliferation and promoted cell apoptosis in vitro. And we illustrated that miR-485-5p was a direct target of NEAT1 and the effect of down-regulated NEAT1 on MM cells was partially reversed by the miR-485-5p antisense oligonucleotide (ASO-miR-485-5p). Further investigation revealed that ABCB8 directly interacted with miR-485-5p. Similarly, in vivo experiments confirmed that down-regulated NEAT1 inhibited tumor growth and ABCB8 expression. Taken together, our results demonstrate for the first time that NEAT1/miR-485-5p/ABCB8 axis may be a key pathway for the development and progression of MM, and they may provide a novel avenue for targeted therapy.

Glycolytic metabolism generates energy and intermediates for biomass production. Tumor-associated glycolysis is upregulated compared to normal tissues in response to tumor cell-autonomous or non-autonomous stimuli. The consequences of this upregulation are twofold. First, the metabolic effects of glycolysis become predominant over those mediated by oxidative metabolism. Second, overexpressed components of the glycolytic pathway (i.e. enzymes or metabolites) acquire new functions unrelated to their metabolic effects and which are referred to as "moonlighting" functions. These functions include induction of mutations and other tumor-initiating events, effects on cancer stem cells, induction of increased expression and/or activity of oncoproteins, epigenetic and transcriptional modifications, bypassing of senescence and induction of proliferation, promotion of DNA damage repair and prevention of DNA damage, antiapoptotic effects, inhibition of drug influx or increase of drug efflux. Upregulated metabolic functions and acquisition of new, non-metabolic functions lead to biological effects that support tumorigenesis: promotion of tumor initiation, stimulation of tumor cell proliferation and primary tumor growth, induction of epithelial-mesenchymal transition, autophagy and metastasis, immunosuppressive effects, induction of drug resistance and effects on tumor accessory cells. These effects have negative consequences on the prognosis of tumor patients. On these grounds, it does not come to surprise that tumor-associated glycolysis has become a target of interest in antitumor drug discovery. So far, however, clinical results with glycolysis inhibitors have fallen short of expectations. In this review we propose approaches that may allow to bypass some of the difficulties that have been encountered so far with the therapeutic use of glycolysis inhibitors., Competing Interests: Declaration of competing interest All authors declare no conflict of interest., (Copyright © 2024. Published by Elsevier Inc.)

Background: Transformed lymphoma occurs when indolent lymphoma transforms into more aggressive lymphoma usually associated with poor prognosis., Methods: In this study, we analysed the immunophenotypes, prognostic factors and outcomes of 35 patients with transformed lymphoma from among 306 marginal zone lymphoma (MZL), 544 follicular lymphoma (FL) and 871 chronic lymphocytic leukaemia/small lymphocytic lymphoma (CLL/SLL) cases. In addition, we performed whole-exome sequencing study of seven transformed MZL (tMZL) cases., Results: Our results demonstrate that the median time from indolent lymphoma diagnosis to transformed DLBCL was 35 months (range, 14-53 months). The 5-year overall survival (OS) and progression-free survival (PFS) rates after histological transformation (HT) were 50% and 26%, respectively. Kaplan-Meier survival analysis revealed that asynchronous HT and transformed CLL/SLL (tCLL/SLL) were significant adverse prognostic factors for OS after DLBCL HT. We identified mutations involvement in chromatin remodelling ( CREBBP and EP300 ) and regulators of NF-κB signalling ( TNFAIP3, BCL10, MYD88, CD79B and CARD11 ) were affected in tMZL., Conclusion: Whole-exome sequencing and copy-number analysis revealed that tMZL derives from the divergent evolution of an ancestral common progenitor clone (CPC). Collectively, this study provides clinicopathological characteristics of three common types of transformed lymphomas and the genetic profile of tMZL with diagnostic and therapeutic implications.

B-cell malignancies, such as chronic lymphocytic leukemia (CLL) and multiple myeloma (MM), remain incurable, with MM particularly prone to relapse. Our study introduces a novel mouse model with active RANK signaling and the TCL1 oncogene, displaying both CLL and MM phenotypes. In younger mice, TCL1 and RANK expression expands CLL-like B1-lymphocytes, while MM originates from B2-cells, becoming predominant in later stages and leading to severe disease progression and mortality. The induced MM mimics human disease, exhibiting features like clonal plasma cell expansion, paraproteinemia, anemia, and kidney and bone failure, as well as critical immunosurveillance strategies that promote a tumor-supportive microenvironment. This research elucidates the differential impacts of RANK activation in B1- and B2-cells and underscores the distinct roles of single versus combined oncogenes in B-cell malignancies. We also demonstrate that human MM cells express RANK and that inhibiting RANK signaling can reduce MM progression in a xenotransplantation model. Our study provides a rationale for further investigating the effects of RANK signaling in B-cell transformation and the shaping of a tumor-promoting microenvironment., (© 2024. The Author(s).)

Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Transformation from non-small cell lung cancer (NSCLC) to small cell lung cancer (SCLC) is rare and is associated with poor prognosis. However, the standard treatment protocols for patients with SCLC transformation remain unknown. Here, we report the case of a patient with advanced EGFR exon 19 deletion (19del) NSCLC who underwent SCLC transformation during targeted therapy. Biopsies and genetic testing were performed to adjust treatment regimens accordingly. The patient responded favorably to a combined treatment regimen comprising etoposide plus cisplatin chemotherapy and adebrelimab plus osimertinib. This case highlights the critical importance of acknowledging tumor heterogeneity in clinical decision-making and identifying potentially effective treatment options for patients with SCLC transformation. Additionally, we reviewed cases of the transformation of NSCLC to SCLC from 2017 to 2023., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Li, Luan, Zhang, Wang, Guo, Lv, Qiu and Zhao.)

Rationale : Immunosuppressive tumor microenvironment (iTME) plays an important role in carcinogenesis, and some macrophage subsets are associated with iTME generation. However, the sub-population characterization of macrophages in oral carcinogenesis remains largely unclear. Here, we investigated the immunosuppressive status with focus on function of a macrophage subset that expressed indoleamine 2,3 dioxygenase 1 (Macro-IDO1) in oral carcinogenesis. Methods : We built a single cell transcriptome atlas from 3 patients simultaneously containing oral squamous cell carcinoma (OSCC), precancerous oral leukoplakia (preca-OLK) and paracancerous tissue (PCA). Through single-cell RNA sequencing and further validation using multicolor immunofluorescence staining and the in vitro / in vivo experiments, the immunosuppressive cell profiles were built and the role of a macrophage subset that expressed indoleamine 2,3 dioxygenase 1 (Macro-IDO1) in the malignant transformation of oral leukoplakia was evaluated. Results : The iTME formed at preca-OLK stage, as evidenced by increased exhausted T cells, Tregs and some special subsets of macrophages and fibroblasts. Macro-IDO1 was predominantly enriched in preca-OLK and OSCC, distributed near exhausted T cells and possessed tumor associated macrophage transformation potentials. Functional analysis revealed the established immunosuppressive role of Macro-IDO1 in preca-OLK and OSCC: enriching the immunosuppression related genes; having an established level of immune checkpoint score; exerting strong immunosuppressive interaction with T cells; positively correlating with the CD8-exhausted. The immunosuppression related gene expression of macrophages also increased in preca-OLK/OSCC compared to PCA. The use of the IDO1 inhibitor reduced 4NQO induced oral carcinogenesis in mice. Mechanistically, IFN-γ-JAK-STAT pathway was associated with IDO1 upregulation in OLK and OSCC. Conclusions : These results highlight that Macro-IDO1-enriched in preca-OLK possesses a strong immunosuppressive role and contributes to oral carcinogenesis, providing a potential target for preventing precancerous legions from transformation into OSCC., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

The early mechanisms of spontaneous tumor initiation that precede malignancy are largely unknown. We show that reduced aPKC levels correlate with stem cell loss and the induction of revival and metaplastic programs in serrated- and conventional-initiated premalignant lesions, which is perpetuated in colorectal cancers (CRCs). Acute inactivation of PKCλ/ι in vivo and in mouse organoids is sufficient to stimulate JNK in non-transformed intestinal epithelial cells (IECs), which promotes cell death and the rapid loss of the intestinal stem cells (ISCs), including those that are LGR5 + . This is followed by the accumulation of revival stem cells (RSCs) at the bottom of the crypt and fetal-metaplastic cells (FMCs) at the top, creating two spatiotemporally distinct cell populations that depend on JNK-induced AP-1 and YAP. These cell lineage changes are maintained during cancer initiation and progression and determine the aggressive phenotype of human CRC, irrespective of their serrated or conventional origin., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Objective: This study aimed to evaluate the effect of exosomes derived from gastric cancer cells on the phenotypic transformation of hepatic stellate cells (HSCs) and the effect of HSC activation on the malignant behavior of gastric cancer cells, including its molecular mechanism., Methods: Exosomes derived from the human gastric adenocarcinoma cell line AGS were extracted and purified by polymer precipitation and ultrafiltration, respectively. The exosomes' morphologic characteristics were observed using transmission electron microscopy, particle size was determined through nanoparticle-tracking analysis, and marker proteins were detected using western blotting. Exosome uptake by LX-2 HSCs was observed through fluorescence-based tracing. Reverse transcription quantitative PCR (RT-qPCR) was used to detect the messenger RNA (mRNA) expression of alpha-smooth muscle actin (α-SMA) and fibroblast activation protein (FAP). Using functional assays, the effects of LX-2 HSC activation on the biological behavior of malignant gastric cancer cells were evaluated. The effects of LX-2 HSC activation on the protein expression of epithelial-mesenchymal transition (EMT)-related genes and β-catenin were evaluated via western blotting., Results: The extracted particles conformed to the definitions of exosomes and were thus considered gastric cancer cell-derived exosomes. Fluorescence-based tracing successfully demonstrated that exosomes were enriched in LX-2 HSCs. RT-qPCR revealed that the mRNA expression of the cancer-associated fibroblast markers α-SMA and FAP was significantly increased. LX-2 HSC activation considerably enhanced gastric cancer cell proliferation, invasion, and migration. Western blotting showed that the expression of the EMT-related epithelial marker E-cadherin was significantly downregulated, whereas the expression of interstitial markers (N-cadherin and vimentin) and β-catenin was remarkably upregulated in gastric cancer cells., Conclusion: Exosomes derived from gastric cancer cells promoted phenotypic transformation of HSCs and activated HSCs to become tumor-associated fibroblasts. Gastric cancer cell-derived cells significantly enhanced gastric cancer cell proliferation, invasion, and migration after HSC activation, which may promote EMT of gastric cancer cells through the Wnt/β-catenin pathway., (Copyright © 2024 Copyright: © 2024 Journal of Cancer Research and Therapeutics.)

Lung cancer remains the leading cause of cancer-related deaths, with cigarette smoking being the most critical factor, linked to nearly 90% of lung cancer cases. NNK, a highly carcinogenic nitrosamine found in tobacco, is implicated in the lung cancer-causing effects of cigarette smoke. Although NNK is known to mutate or activate certain oncogenes, its potential interaction with p27 in modulating these carcinogenic effects is currently unexplored. Recent studies have identified specific downregulation of p27 in human squamous cell carcinoma, in contrast to adenocarcinoma. Additionally, exposure to NNK significantly suppresses p27 expression in human bronchial epithelial cells. Subsequent studies indicates that the downregulation of p27 is pivotal in NNK-induced cell transformation. Mechanistic investigations have shown that reduced p27 expression leads to increased level of ITCH, which facilitates the degradation of Jun B protein. This degradation in turn, augments miR-494 expression and its direct regulation of JAK1 mRNA stability and protein expression, ultimately activating STAT3 and driving cell transformation. In summary, our findings reveal that: (1) the downregulation of p27 increases Jun B expression by upregulating Jun B E3 ligase ITCH, which then boosts miR-494 transcription; (2) Elevated miR-494 directly binds to 3'-UTR of JAK1 mRNA, enhancing its stability and protein expression; and (3) The JAK1/STAT3 pathway is a downstream effector of p27, mediating the oncogenic effect of NNK in lung cancer. These findings provide significant insight into understanding the participation of mechanisms underlying p27 inhibition of NNK induced lung squamous cell carcinogenic effect., (© 2024 The Author(s). Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Aneuploidy is nearly ubiquitous in tumor genomes, but the role of aneuploidy in the early stages of cancer evolution remains unclear. Here, by inducing heterogeneous aneuploidy in non-transformed human colon organoids (colonoids), we investigated how the effects of aneuploidy on cell growth and differentiation may promote malignant transformation. Previous work implicated p53 activation as a downstream response to aneuploidy induction. We found that simple aneuploidy, characterized by 1-3 gained or lost chromosomes, resulted in little or modest p53 activation and cell cycle arrest when compared with more complex aneuploid cells. Single-cell RNA sequencing analysis revealed that the degree of p53 activation was strongly correlated with karyotype complexity. Single-cell tracking showed that cells could continue to divide despite the observation of one to a few lagging chromosomes. Unexpectedly, colonoids with simple aneuploidy exhibited impaired differentiation after niche factor withdrawal. These findings demonstrate that simple aneuploid cells can escape p53 surveillance and may contribute to niche factor-independent growth of cancer-initiating colon stem cells.

Epithelial-mesenchymal transition (EMT) plays a pivotal role in the development and progression of many cancers. Partial EMT (pEMT) could represent a critical step in tumor migration and dissemination. Sarcomatoid renal cell carcinoma (sRCC) is an aggressive form of renal cell carcinoma (RCC) composed of a carcinomatous (sRCC-Ca) and sarcomatous (sRCC-Sa) component. The role of (p)EMT in the progression of RCC to sRCC remains unclear. The aim of this study was to investigate the involvement of (p)EMT in RCC and sRCC. Tissue samples from 10 patients with clear cell RCC (ccRCC) and 10 patients with sRCC were selected. The expression of main EMT markers (miR-200 family, miR-205, SNAI1/2, TWIST1/2, ZEB1/2, CDH1/2, VIM) was analyzed by qPCR in ccRCC, sRCC-Ca, and sRCC-Sa and compared to non-neoplastic tissue and between both groups. Expression of E-cadherin, N-cadherin, vimentin and ZEB2 was analyzed using immunohistochemistry. miR-200c was downregulated in sRCC-Ca compared to ccRCC, while miR-200a was downregulated in sRCC-Sa compared to ccRCC. CDH1 was downregulated in sRCC-Sa when compared to any other group. ZEB2 was downregulated in ccRCC and sRCC compared to corresponding non-neoplastic kidney. A positive correlation was observed between CDH1 expression and miR-200a/b/c. Our results suggest that full EMT is not present in sRCC. Instead, discreet molecular differences exist between ccRCC, sRCC-Ca, and sRCC-Sa, possibly representing distinct intermediary states undergoing pEMT., Competing Interests: Declaration of competing interest The authors declare that there are no conflicts of interest., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

The tumour evolution model posits that malignant transformation is preceded by randomly distributed driver mutations in cancer genes, which cause clonal expansions in phenotypically normal tissues. Although clonal expansions can remodel entire tissues 1-3 , the mechanisms that result in only a small number of clones transforming into malignant tumours remain unknown. Here we develop an in vivo single-cell CRISPR strategy to systematically investigate tissue-wide clonal dynamics of the 150 most frequently mutated squamous cell carcinoma genes. We couple ultrasound-guided in utero lentiviral microinjections, single-cell RNA sequencing and guide capture to longitudinally monitor clonal expansions and document their underlying gene programmes at single-cell transcriptomic resolution. We uncover a tumour necrosis factor (TNF) signalling module, which is dependent on TNF receptor 1 and involving macrophages, that acts as a generalizable driver of clonal expansions in epithelial tissues. Conversely, during tumorigenesis, the TNF signalling module is downregulated. Instead, we identify a subpopulation of invasive cancer cells that switch to an autocrine TNF gene programme associated with epithelial-mesenchymal transition. Finally, we provide in vivo evidence that the autocrine TNF gene programme is sufficient to mediate invasive properties and show that the TNF signature correlates with shorter overall survival of patients with squamous cell carcinoma. Collectively, our study demonstrates the power of applying in vivo single-cell CRISPR screening to mammalian tissues, unveils distinct TNF programmes in tumour evolution and highlights the importance of understanding the relationship between clonal expansions in epithelia and tumorigenesis., (© 2024. The Author(s).)

Neuroendocrine (NE) transformation is a mechanism of resistance to targeted therapy in lung and prostate adenocarcinomas leading to poor prognosis. Up to date, even if patients at high risk of transformation can be identified by the occurrence of Tumor Protein P53 (TP53) and Retinoblastoma Transcriptional Corepressor 1 (RB1) mutations in their tumors, no therapeutic strategies are available to prevent or delay histological transformation. Upregulation of the cell cycle kinase Cell Division Cycle 7 (CDC7) occurred in tumors during the initial steps of NE transformation, already after TP53/RB1 co-inactivation, leading to induced sensitivity to the CDC7 inhibitor simurosertib. CDC7 inhibition suppressed NE transdifferentiation and extended response to targeted therapy in in vivo models of NE transformation by inducing the proteasome-mediated degradation of the MYC Proto-Oncogen (MYC), implicated in stemness and histological transformation. Ectopic overexpression of a degradation-resistant MYC isoform reestablished the NE transformation phenotype observed on targeted therapy, even in the presence of simurosertib. CDC7 inhibition also markedly extended response to standard cytotoxics (cisplatin, irinotecan) in lung and prostate small cell carcinoma models. These results nominate CDC7 inhibition as a therapeutic strategy to constrain lineage plasticity, as well as to effectively treat NE tumors de novo or after transformation. As simurosertib clinical efficacy trials are ongoing, this concept could be readily translated for patients at risk of transformation., (© 2024. The Author(s).)

The clinical impact of therapy-related acute leukemias is increasing with the extension of cancer-related survival; however, the origins remain largely unknown. Acute erythroleukemia (AEL), a rare unfavorable type of myeloid neoplasia, may also develop secondary to cytotoxic therapy. The disorder is featured by specific genetic alterations, most importantly multi-allelic mutations of the TP53 gene. While AEL might appear as a part of the therapy-related MDS/AML, spectrum information regarding the genetic complexity and progression is largely missing. We present two AEL cases arising after cytotoxic therapy and melphalan-based myeloablation/autologous peripheral stem cell transplantation due to multiple myeloma (MM). As stated, multiple pathogenic TP53 variants were present unrelated to preexisting MM, in parallel with uninvolved/wild-type hemopoiesis. Potential mechanisms of leukemic transformation are discussed, which include (1) preexisting preneoplastic hemopoietic stem cells (HSC) serving as the common origin for both MM and AEL, (2) the generation and intramedullary survival of p53-deficient post-chemotherapy HSCs, (3) reinoculation of mobilized autologous TP53 mutated HSCs, and (4) melphalan treatment-related late-onset myelodysplasia/leukemia with newly acquired TP53 mutations.

Most of essential thrombocythemia (ET) patients have the clone harboring a mutation in one of the JAK2, CALR, or MPL gene, and these clones generally acquire additional mutations at transformation to acute myeloid leukemia (AML). However, the proliferation of triple-negative clones has sometimes been observed at AML transformation. To clarify the clonal evolution of ET to AML, we analyzed paired samples at ET and AML transformation in eight patients. We identified that JAK2-unmutated AML clones proliferated at AML transformation in three patients in whom the JAK2-mutated clone was dominant at ET. In two patients, TET2-mutated, but not JAK2-mutated, clones might be common initiating clones for ET and transformed AML. In a patient with JAK2-mutated ET, SMARCC2, UBR4, and ZNF143, but not JAK2, -mutated clones proliferated at AML transformation. Precise analysis using single-cell sorted CD34 + /CD38 - fractions suggested that ET clone with JAK2-mutated and AML clone with TP53 mutation was derived from the common clone with these mutations. Although further study is required to clarify the biological significance of SMARCC2, UBR4, and ZNF143 mutations during disease progression of ET and AML transformation, the present results demonstrate the possibility of a common initial clone involved in both ET and transformed AML., (© 2024. The Author(s).)

Accumulating evidence suggests that caspase-3 plays critical roles beyond apoptosis, serving pro-survival functions in malignant transformation and tumorigenesis. However, the mechanism of non-apoptotic action of caspase-3 in oncogenic transformation remains unclear. In the present study, we show that caspase-3 is consistently activated in malignant transformation induced by exogenous expression of oncogenic cocktail (c-Myc, p53DD, Oct-4, and H-Ras) in vitro as well as in the mouse mammary tumor virus-polyomavirus middle T antigen (MMTV-PyMT) mouse model of breast cancer. Genetic ablation of caspase-3 significantly attenuated oncogene-induced transformation of mammalian cells and delayed breast cancer progression in MMTV-PyMT transgenic mice. Mechanistically, active caspase-3 triggers the translocation of endonuclease G (EndoG) from mitochondria, which migrates to the nucleus, thereby induces phosphorylation of Src-STAT3 signaling pathway to facilitate oncogenic transformation. Taken together, our data suggest that caspase-3 plays pivotal role in facilitating rather than suppressing oncogene-induced malignant transformation of mammalian cells., (© 2024. The Author(s).)

YT521-B homology (YTH) domain family (YTHDF) proteins serve as readers that directly recognise m6A modifications. In this study, we aim to probe the role of YTHDF1 in environmental carcinogen-induced malignant transformation of gastric cells and gastric cancer (GC) carcinogenesis. We established a long-term low-dose MNU-induced malignant transformation model in gastric epithelial cells. In vivo and in vitro experiments were conducted to validate the malignant phenotype and characterise the roles of YTHDF1 and its downstream genes in malignant transformation cells. Additionally, we explored downstream m6A modification targets of YTHDF1 using RNA-sequencing, RNA immunoprecipitation, and proteomics analyses, and conducted validation experiments in cell experiments and clinical samples. Long-term low-dose exposure of MNU converted normal Gges-1 cells into malignant cells. YTHDF1 mRNA and protein expression are increased in MNU-induced malignant cells (p<0.001). Meanwhile, YTHDF1 knockdown inhibits the malignant potential of MNU-treated cells (p<0.01). YTHDF1 knockdown specifically suppresses HSPH1 protein, but not RNA levels. RIP-qPCR validates HSPH1 is the target of YTHDF1 (p<0.01). HSPH1 knockdown impairs the malignant potential of MNU-induced transformed cells. The increased expression of the key regulatory factor YTHDF1 in MNU-induced gastric carcinogenesis affects malignant transformation and tumorigenesis by regulating the translation of downstream HSPH1. These findings provide new potential targets for preventing and treating environmental chemical-induced gastric carcinogenesis., (© 2024 The Authors. Cell Proliferation published by Beijing Institute for Stem Cell and Regenerative Medicine and John Wiley & Sons Ltd.)

Lung cancer is the leading cause of cancer death and includes two major types: non-small-cell lung cancer (NSCLC) and small-cell lung cancer (SCLC), accounting for 85% and 15% of cases, respectively. Non-small-cell lung cancer harboring actionable driver mutations is generally treated with tyrosine kinase inhibitors (TKIs) molecularly targeting individual oncogenes. Although TKIs have greatly contributed to better clinical outcomes, acquired resistance to them inevitably occurs. Histologic or lineage transformation is a rare but well-documented off-target mechanism associated with acquired resistance, and has been identified in settings following treatment with multiple different TKIs and other drugs. It includes neuroendocrine transformation, squamous cell transformation, and epithelial-to-mesenchymal transition. Here, we review the clinicopathologic features of transformed tumors and current understanding of the key genetic alterations and biologic mechanism of lineage transformation in NSCLC, particularly TKI-triggered transformation., (© 2024 The Author(s). Cancer Science published by John Wiley & Sons Australia, Ltd on behalf of Japanese Cancer Association.)

In this commentary, we discuss the investigation into reports of T-cell malignancies following chimeric antigen receptor T-cell therapy. We argue that although these cases should be thoroughly examined, current data suggest that such risks with autologous chimeric antigen receptor T cells are remarkably low compared with other cancer treatments. We also emphasize the importance of continued research, transparent reporting, and participation in postauthorization safety studies., (©2024 American Association for Cancer Research.)

Accounting for 10-20% of breast cancer cases, triple-negative breast cancer (TNBC) is associated with a disproportionate number of breast cancer deaths. One challenge in studying TNBC is its genomic profile: with the exception of TP53 loss, most breast cancer tumors are characterized by a high number of copy number alterations (CNAs), making modeling the disease in whole animals challenging. We computationally analyzed 186 CNA regions previously identified in breast cancer tumors to rank genes within each region by likelihood of acting as a tumor driver. We then used a Drosophila p53-Myc TNBC model to identify 48 genes as functional drivers. To demonstrate the utility of this functional database, we established six 3-hit models; altering candidate genes led to increased aspects of transformation as well as resistance to the chemotherapeutic drug fluorouracil. Our work provides a functional database of CNA-associated TNBC drivers, and a template for an integrated computational/whole-animal approach to identify functional drivers of transformation and drug resistance within CNAs in other tumor types., Competing Interests: Competing interests The authors declare no competing or financial interests., (© 2024. Published by The Company of Biologists Ltd.)

A pervasive view is that undifferentiated stem cells are alone responsible for generating all other cells and are the origins of cancer. However, emerging evidence demonstrates fully differentiated cells are plastic, can be coaxed to proliferate, and also play essential roles in tissue maintenance, regeneration, and tumorigenesis. Here, we review the mechanisms governing how differentiated cells become cancer cells. First, we examine the unique characteristics of differentiated cell division, focusing on why differentiated cells are more susceptible than stem cells to accumulating mutations. Next, we investigate why the evolution of multicellularity in animals likely required plastic differentiated cells that maintain the capacity to return to the cell cycle and required the tumor suppressor p53. Finally, we examine an example of an evolutionarily conserved program for the plasticity of differentiated cells, paligenosis, which helps explain the origins of cancers that arise in adults. Altogether, we highlight new perspectives for understanding the development of cancer and new strategies for preventing carcinogenic cellular transformations from occurring., (© 2024. The Author(s).)

Introduction: Nucleoporin 98 (NUP98) fusion proteins are recurrently found in leukemia and are associated with unfavorable clinical outcomes. They are distributed to the nucleus and contribute to leukemogenesis via aberrant transcriptional regulation. We previously identified NUP98-BPTF (NB) fusion in patients with T-cell acute lymphoblastic leukemia (T-ALL) using next-generation sequencing. The FG-repeat of NUP98 and the PHD finger and bromodomain of bromodomain PHD finger transcription factor (BPTF) are retained in the fusion. Like other NUP98 fusion proteins, NB is considered to regulate genes that are essential for leukemogenesis. However, its target genes or pathways remain unknown., Materials and Methods: To investigate the potential oncogenic properties of the NB fusion protein, we lentivirally transduced a doxycycline-inducible NB expression vector into mouse NIH3T3 fibroblasts and human Jurkat T-ALL cells., Results: NB promoted the transformation of mouse NIH3T3 fibroblasts by upregulating the proto-oncogene Pim1, which encodes a serine/threonine kinase. NB transcriptionally regulated Pim1 expression by binding to its promoter and activated MYC and mTORC1 signaling. PIM1 knockdown or pharmacological inhibition of mTORC1 signaling suppressed NB-induced NIH3T3 cell transformation. Furthermore, NB enhanced the survival of human Jurkat T-ALL cells by inactivating the pro-apoptotic protein BCL2-associated agonist of cell death (BAD)., Conclusion: We demonstrated the pivotal role of NB in cell transformation and survival and identified PIM1as a key downstream target of NB. These findings propose a promising therapeutic strategy for patients with NB fusion-positive leukemia., (© 2024 The Author(s). Cancer Medicine published by John Wiley & Sons Ltd.)

Background: The cell cycle of mammary stem cells must be tightly regulated to ensure normal homeostasis of the mammary gland to prevent abnormal proliferation and susceptibility to tumorigenesis. The atypical cell cycle regulator, Spy1 can override cell cycle checkpoints, including those activated by the tumour suppressor p53 which mediates mammary stem cell homeostasis. Spy1 has also been shown to promote expansion of select stem cell populations in other developmental systems. Spy1 protein is elevated during proliferative stages of mammary gland development, is found at higher levels in human breast cancers, and promotes susceptibility to mammary tumourigenesis when combined with loss of p53. We hypothesized that Spy1 cooperates with loss of p53 to increase susceptibility to tumour initiation due to changes in susceptible mammary stem cell populations during development and drives the formation of more aggressive stem like tumours., Methods: Using a transgenic mouse model driving expression of Spy1 within the mammary gland, mammary development and stemness were assessed. These mice were intercrossed with p53 null mice to study the tumourigenic properties of Spy1 driven p53 null tumours, as well as global changes in signaling via RNA sequencing analysis., Results: We show that elevated levels of Spy1 leads to expansion of mammary stem cells, even in the presence of p53, and an increase in mammary tumour formation. Spy1-driven tumours have an increased cancer stem cell population, decreased checkpoint signaling, and demonstrate an increase in therapy resistance. Loss of Spy1 decreases tumor onset and reduces the cancer stem cell population., Conclusions: This data demonstrates the potential of Spy1 to expand mammary stem cell populations and contribute to the initiation and progression of aggressive, breast cancers with increased cancer stem cell populations., (© 2024. The Author(s).)