TGF-β promotes heterogeneity and drug resistance in squamous cell carcinoma

Bioprinted Fibroblast Mediated Heterogeneous Tumor Microenvironment for Studying Tumor-Stroma Interaction and Drug Screening

Cancer-associated fibroblasts (CAFs) are crucial stromal cells in the tumor microenvironment, affecting cancer growth, angiogenesis, and matrix remodeling. Developing an effective in vitro tumor model that accurately recapitulates the dynamic interplay between tumor and stromal cells remains a challenge. In this study, a 3D bioprinted fibroblast - mediated heterogeneous breast tumor model was created, with tumor cells and fibroblasts in a bionic matrix. The impact of transforming growth factor-β （TGF-β） on the dynamic transformation of normal fibroblasts into CAFs and its subsequent influence on tumor cells is further investigated. These findings reveales a profound correlation between CAFs and several critical biological processes, including epithelial-mesenchymal transition (EMT), extracellular matrix (ECM) remodeling, gene expression profiles, and tumor progression. Furthermore, tumor models incorporating CAFs exhibits reduced drug sensitivity compared to models containing tumor cells alone or models co-cultured with normal fibroblasts. These results underscore the potential of the in vitro fibroblast-mediated heterogeneous tumor model to simulate real-life physiological conditions, thereby offering a more effective drug screening platform for elucidating tumor pathogenesis and facilitating drug design prior to animal and clinical trials. This model's establishment promotes the understanding of tumor-stromal interactions and their therapeutic implications.

CD133+PD-L1+ cancer cells confer resistance to adoptively transferred engineered macrophage-based therapy in melanoma

Adoptive transfer of genetically or nanoparticle-engineered macrophages represents a promising cell therapy modality for treatment of solid tumor. However, the therapeutic efficacy is suboptimal without achieving a complete tumor regression, and the underlying mechanism remains elusive. Here, we discover a subpopulation of cancer cells with upregulated CD133 and programmed death-ligand 1 in mouse melanoma, resistant to the phagocytosis by the transferred macrophages. Compared to the CD133-PD-L1- cancer cells, the CD133+PD-L1+ cancer cells express higher transforming growth factor-β signaling molecules to foster a resistant tumor niche, that restricts the trafficking of the transferred macrophages by stiffened extracellular matrix, and inhibits their cell-killing capability by immunosuppressive factors. The CD133+PD-L1+ cancer cells exhibit tumorigenic potential. The CD133+PD-L1+ cells are further identified in the clinically metastatic melanoma. Hyperthermia reverses the resistance of CD133+PD-L1+ cancer cells through upregulating the 'eat me' signal calreticulin, significantly improving the efficacy of adoptive macrophage therapy. Our findings demonstrate the mechanism of resistance to adoptive macrophage therapy, and provide a de novo strategy to counteract the resistance.

Exploring the potential of TGFβ as a diagnostic marker and therapeutic target against cancer

Transforming Growth Factor-beta (TGF-β) is a multifunctional cytokine that exerts its biological effects through a complex process of activation and signaling. Initially synthesized in an inactive form bound to latency-associated peptide (LAP), TGF-β requires release from the extracellular matrix via proteolytic cleavage or integrin-mediated activation to engage with its receptors. Once active, TGF-β binds to type II receptor (TβRII), which then phosphorylates and activates type I receptor (TβRI), triggering downstream signaling cascades, including both Smad-dependent and non-Smad pathways. These signaling cascades regulate key processes like cell growth, differentiation, migration, and immune response modulation, thereby influencing tumor development, progression, and treatment outcomes. This review discusses the complex signaling pathways of TGF-β in cancer, including its interactions with other signaling molecules and its involvement in epithelial-mesenchymal transition (EMT) and in evading immune surveillance. Moreover, dysregulated TGF-β signaling due to alterations in receptor expression, mutations in key signaling proteins such as TβRII and Smads, and aberrant activation of non-canonical pathways, contributes significantly to tumor aggressiveness, metastasis, and therapy resistance. The article emphasizes the potential of TGF-β as a diagnostic biomarker for cancer, highlighting its use in early detection, prognosis assessment, and monitoring treatment response. Additionally, it underscores various therapeutic strategies targeting TGF-β, such as small molecule inhibitors, monoclonal antibodies, immunotherapies, and evaluates their efficacy and limitations in preclinical and clinical settings. Finally, the review provides a comprehensive analysis of TGF-β's role as both a diagnostic tool and a therapeutic target, while also discussing the challenges and opportunities in targeting TGF-β signaling for improving cancer treatment outcomes.

Stemness in solid malignancies: coping with immune attack

Immunotherapy has become a key new pillar of cancer treatment, and this has sparked interest in understanding mechanisms of cancer immune evasion. It has long been appreciated that cancers are constituted by heterogeneous populations of tumour cells. This feature is often fuelled by specialized cells that have molecular programs resembling tissue stem cells. Although these cancer stem cells (CSCs) have capacity for unlimited self-renewal and differentiation, it is increasingly evident that some CSCs are capable of achieving remarkable immune resistance. Given that most immunotherapy regiments have overlooked CSC-specific immune-evasive mechanisms, many current treatment strategies often lead to cancer relapse. This Review focuses on advancements in understanding how CSCs in solid tumours achieve their unique immune-evasive properties, enabling them to drive tumour regrowth. Moreover, as cancers often arise from tissue stem cells that acquired oncogenic mutations, we discuss how tissue stem cells undergoing malignant transformation activate intrinsic immune-evasive mechanisms and establish close interactions with suppressive immune cells to escape immune surveillance. In addition, we summarize how in advanced disease stages, CSCs often hijack features of normal stem cells to resist antitumour immunity. Finally, we provide insights in how to design a new generation of cancer immunotherapies to ensure elimination of CSCs.

Oleanolic acid inhibits aldo-keto reductase family 1 member B10-induced cancer stemness and avoids cisplatin-based chemotherapy resistance via the Snail signaling pathway in oral squamous cell carcinoma cell lines

Background/purpose

Oral squamous cell carcinoma (OSCC) is a common malignancy often associated with poor prognosis due to chemoresistance. In this study, we investigated whether arecoline, a major alkaloid in betel nuts, can stimulate aldo-keto reductase family 1 member B10 (AKR1B10) levels in OSCC, promoting cancer stemness and leading to resistance to cisplatin (CDDP)-based chemotherapy.

Materials and methods

Gain- and Loss- of AKR1B10 functions were analyzed using WB and q-PCR of OSCC cells. Stemness, epithelial mesenchymal transition (EMT) markers, and CDDP drug resistance in overexpressed AKR1B10 were also identified.

Results

Upregulated AKR1B10 in OSCC significantly increased cell motility and aggregation. The results also showed that the canonical TGF-β1-Smad3 pathway was involved in arecoline-induced AKR1B10 expression, further increasing cancer stemness with CDDP resistance via the Snail-dependent EMT pathway. Moreover, oleanolic acid (OA) and ROS/RNS (reactive oxygen/nitrogen species) inhibitors effectively reversed AKR1B10-induced CDDP-resistance.

Conclusion

Arecoline-induced ROS/RNS to hyper-activate AKR1B10 in tumor sphere cells via the TGF-β1-Smad3 pathway. Furthermore, AKR1B10 enhanced CDDP resistance in OSCC cells via EMT-inducing markers. Finally, Finally, OA may efficiently target CDDP resistance, reverse stemness in OSCC cells, and have the potential as a novel anticancer drug.

Nrf2 Signaling in Renal Cell Carcinoma: A Potential Candidate for the Development of Novel Therapeutic Strategies

Renal cell carcinoma (RCC) is the most common type of kidney cancer arising from renal tubular epithelial cells and is characterized by a high aggressive behavior and invasiveness that lead to poor prognosis and high mortality rate. Diagnosis of RCC is generally incidental and occurs when the stage is advanced and the disease is already metastatic. The management of RCC is further complicated by an intrinsic resistance of this malignancy to chemotherapy and radiotherapy, which aggravates the prognosis. For these reasons, there is intense research focused on identifying novel biomarkers which may be useful for a better prognostic assessment, as well as molecular markers which could be utilized for targeted therapy. Nuclear factor erythroid 2-related factor 2 (Nrf2) is a transcriptional factor that has been identified as a key modulator of oxidative stress response, and its overexpression is considered a negative prognostic feature in several types of cancers including RCC, since it is involved in various key cancer-promoting functions such as proliferation, anabolic metabolism and resistance to chemotherapy. Given the key role of Nrf2 in promoting tumor progression, this enzyme could be a promising biomarker for a more accurate prediction of RCC course and it can also represent a valuable therapeutic target. In this review, we provide a comprehensive literature analysis of studies that have explored the role of Nrf2 in RCC, underlining the possible implications for targeted therapy.

Lung-resident alveolar macrophages regulate the timing of breast cancer metastasis

Breast disseminated cancer cells (DCCs) can remain dormant in the lungs for extended periods, but the mechanisms limiting their expansion are not well understood. Research indicates that tissue-resident alveolar macrophages suppress breast cancer metastasis in lung alveoli by inducing dormancy. Through ligand-receptor mapping and intravital imaging, it was found that alveolar macrophages express transforming growth factor (TGF)-β2. This expression, along with persistent macrophage-cancer cell interactions via the TGF-βRIII receptor, maintains cancer cells in a dormant state. Depleting alveolar macrophages or losing the TGF-β2 receptor in cancer cells triggers metastatic awakening. Aggressive breast cancer cells are either suppressed by alveolar macrophages or evade this suppression by avoiding interaction and downregulating the TGF-β2 receptor. Restoring TGF-βRIII in aggressive cells reinstates TGF-β2-mediated macrophage growth suppression. Thus, alveolar macrophages act as a metastasis immune barrier, and downregulation of TGF-β2 signaling allows cancer cells to overcome macrophage-mediated growth suppression.

Energy Landscape Reveals the Underlying Mechanism of Cancer-Adipose Conversion in Gene Network Models

Cancer is a systemic heterogeneous disease involving complex molecular networks. Tumor formation involves an epithelial-mesenchymal transition (EMT), which promotes both metastasis and plasticity of cancer cells. Recent experiments have proposed that cancer cells can be transformed into adipocytes via a combination of drugs. However, the underlying mechanisms for how these drugs work, from a molecular network perspective, remain elusive. To reveal the mechanism of cancer-adipose conversion (CAC), this study adopts a systems biology approach by combing mathematical modeling and molecular experiments, based on underlying molecular regulatory networks. Four types of attractors are identified, corresponding to epithelial (E), mesenchymal (M), adipose (A) and partial/intermediate EMT (P) cell states on the CAC landscape. Landscape and transition path results illustrate that intermediate states play critical roles in the cancer to adipose transition. Through a landscape control approach, two new therapeutic strategies for drug combinations are identified, that promote CAC. These predictions are verified by molecular experiments in different cell lines. The combined computational and experimental approach provides a powerful tool to explore molecular mechanisms for cell fate transitions in cancer networks. The results reveal underlying mechanisms of intermediate cell states that govern the CAC, and identified new potential drug combinations to induce cancer adipogenesis.

Cancer stem cells: Masters of all traits

Cancer is a heterogeneous disease, which contributes to its rapid progression and therapeutic failure. Besides interpatient tumor heterogeneity, tumors within a single patient can present with a heterogeneous mix of genetically and phenotypically distinct subclones. These unique subclones can significantly impact the traits of cancer. With the plasticity that intratumoral heterogeneity provides, cancers can easily adapt to changes in their microenvironment and therapeutic exposure. Indeed, tumor cells dynamically shift between a more differentiated, rapidly proliferating state with limited tumorigenic potential and a cancer stem cell (CSC)-like state that resembles undifferentiated cellular precursors and is associated with high tumorigenicity. In this context, CSCs are functionally located at the apex of the tumor hierarchy, contributing to the initiation, maintenance, and progression of tumors, as they also represent the subpopulation of tumor cells most resistant to conventional anti-cancer therapies. Although the CSC model is well established, it is constantly evolving and being reshaped by advancing knowledge on the roles of CSCs in different cancer types. Here, we review the current evidence of how CSCs play a pivotal role in providing the many traits of aggressive tumors while simultaneously evading immunosurveillance and anti-cancer therapy in several cancer types. We discuss the key traits and characteristics of CSCs to provide updated insights into CSC biology and highlight its implications for therapeutic development and improved treatment of aggressive cancers.

Unveiling stem-like traits and chemoresistance mechanisms in ovarian cancer cells through the TGFβ1-PITX2A/B signaling axis

Ovarian cancer (OC) is the deadliest gynecological malignancy, having a high mortality rate due to its asymptomatic nature, chemoresistance, and recurrence. However, the proper mechanistic knowledge behind these phenomena is still inadequate. Cancer recurrence is commonly observed due to cancer stem cells which also show chemoresistance. We aimed to decipher the molecular mechanism behind chemoresistance and stemness in OC. Earlier studies suggested that PITX2, a homeobox transcription factor and, its different isoforms are associated with OC progression upon regulating different signaling pathways. Moreover, they regulate the expression of drug efflux transporters in kidney and colon cancer, rendering chemoresistance properties in the tumor cell. Considering these backgrounds, we decided to look for the role of PITX2 isoforms in promoting stemness and chemoresistance in OC cells. In this study, PITX2A/B has been shown to promote stemness and to enhance the transcription of ABCB1. PITX2 has been discovered to augment ABCB1 gene expression by directly binding to its promoter. To further investigate the regulatory mechanism of PITX2 gene expression, we found that TGFβ signaling could augment the PITX2A/B expression through both SMAD and non-SMAD signaling pathways. Collectively, we conclude that TGFβ1-activated PITX2A/B induces stem-like features and chemoresistance properties in the OC cells.

Innovative optical imaging strategies for monitoring immunotherapy in the tumor microenvironments

BACKGROUND

The tumor microenvironment (TME) plays a critical role in cancer progression and response to immunotherapy. Immunotherapy targeting the immune system has emerged as a promising treatment modality, but challenges in understanding the TME limit its efficacy. Optical imaging strategies offer noninvasive, real-time insights into the interactions between immune cells and the TME.

OBJECTIVE

This review assesses the progress of optical imaging technologies in monitoring immunotherapy within the TME and explores their potential applications in clinical trials and personalized cancer treatment.

METHODS

This is a comprehensive literature review based on the advances in optical imaging modalities including fluorescence imaging (FLI), bioluminescence imaging (BLI), and photoacoustic imaging (PAI). These modalities were analyzed for their capacity to provide high-resolution, real-time imaging of immune cell dynamics, tumor vasculature, and other critical components of the TME.

RESULTS

Optical imaging techniques have shown significant potential in tracking immune cell infiltration, assessing immune checkpoint inhibitors, and visualizing drug delivery within the TME. Technologies like FLI and BLI are pivotal in tracking immune responses in preclinical models, while PAI provides functional imaging with deeper tissue penetration. The integration of these modalities with immunotherapy holds promise for improving treatment monitoring and outcomes.

CONCLUSION

Optical imaging is a powerful tool for understanding the complexities of the TME and optimizing immunotherapy. Further advancements in imaging technologies, combined with nanomaterial-based approaches, could pave the way for enhanced diagnostic accuracy and therapeutic efficacy in cancer treatment.

Stabilization of TGF-β Receptor 1 by a Receptor-Associated Adaptor Dictates Feedback Activation of the TGF-β Signaling Pathway to Maintain Liver Cancer Stemness and Drug Resistance

Dysregulation of the transforming growth factor-β (TGF-β) signaling pathway regulates cancer stem cells (CSCs) and drug sensitivity, whereas it remains largely unknown how feedback regulatory mechanisms are hijacked to fuel drug-resistant CSCs. Through a genome-wide CRISPR activation screen utilizing stem-like drug-resistant properties as a readout, the TGF-β receptor-associated binding protein 1 (TGFBRAP1) is identified as a TGF-β-inducible positive feedback regulator that governs sensitivity to tyrosine kinase inhibitors (TKIs) and promotes liver cancer stemness. By interacting with and stabilizing the TGF-β receptor type 1 (TGFBR1), TGFBRAP1 plays an important role in potentiating TGF-β signaling. Mechanistically, TGFBRAP1 competes with E3 ubiquitin ligases Smurf1/2 for binding to TGFΒR1, leading to impaired receptor poly-ubiquitination and proteasomal degradation. Moreover, hyperactive TGF-β signaling in turn up-regulates TGFBRAP1 expression in drug-resistant CSC-like cells, thereby constituting a previously uncharacterized feedback mechanism to amplify TGF-β signaling. As such, TGFBRAP1 expression is correlated with TGFΒR1 levels and TGF-β signaling activity in hepatocellular carcinoma (HCC) tissues, as well as overall survival and disease recurrence in multiple HCC cohorts. Therapeutically, blocking TGFBRAP1-mediated stabilization of TGFBR1 by selective inhibitors alleviates Regorafenib resistance via reducing CSCs. Collectively, targeting feedback machinery of TGF-β signaling pathway may be an actionable approach to mitigate drug resistance and liver cancer stemness.

Cancer stem cells release interleukin-33 within large oncosomes to promote immunosuppressive differentiation of macrophage precursors

In squamous cell carcinoma (SCC), macrophages responding to interleukin (IL)-33 create a TGF-β-rich stromal niche that maintains cancer stem cells (CSCs), which evade chemotherapy-induced apoptosis in part via activation of the NRF2 antioxidant program. Here, we examined how IL-33 derived from CSCs facilitates the development of an immunosuppressive microenvironment. CSCs with high NRF2 activity redistributed nuclear IL-33 to the cytoplasm and released IL-33 as cargo of large oncosomes (LOs). Mechanistically, NRF2 increased the expression of the lipid scramblase ATG9B, which exposed an "eat me" signal on the LO surface, leading to annexin A1 (ANXA1) loading. These LOs promoted the differentiation of AXNA1 receptor+ myeloid precursors into immunosuppressive macrophages. Blocking ATG9B's scramblase activity or depleting ANXA1 decreased niche macrophages and hindered tumor progression. Thus, IL-33 is released from live CSCs via LOs to promote the differentiation of alternatively activated macrophage, with potential relevance to other settings of inflammation and tissue repair.

Single-cell decoding of drug induced transcriptomic reprogramming in triple negative breast cancers

BACKGROUND

The encoding of cell intrinsic drug resistance states in breast cancer reflects the contributions of genomic and non-genomic variations and requires accurate estimation of clonal fitness from co-measurement of transcriptomic and genomic data. Somatic copy number (CN) variation is the dominant mutational mechanism leading to transcriptional variation and notably contributes to platinum chemotherapy resistance cell states. Here, we deploy time series measurements of triple negative breast cancer (TNBC) single-cell transcriptomes, along with co-measured single-cell CN fitness, identifying genomic and transcriptomic mechanisms in drug-associated transcriptional cell states.

RESULTS

We present scRNA-seq data (53,641 filtered cells) from serial passaging TNBC patient-derived xenograft (PDX) experiments spanning 2.5 years, matched with genomic single-cell CN data from the same samples. Our findings reveal distinct clonal responses within TNBC tumors exposed to platinum. Clones with high drug fitness undergo clonal sweeps and show subtle transcriptional reversion, while those with weak fitness exhibit dynamic transcription upon drug withdrawal. Pathway analysis highlights convergence on epithelial-mesenchymal transition and cytokine signaling, associated with resistance. Furthermore, pseudotime analysis demonstrates hysteresis in transcriptional reversion, indicating generation of new intermediate transcriptional states upon platinum exposure.

CONCLUSIONS

Within a polyclonal tumor, clones with strong genotype-associated fitness under platinum remained fixed, minimizing transcriptional reversion upon drug withdrawal. Conversely, clones with weaker fitness display non-genomic transcriptional plasticity. This suggests CN-associated and CN-independent transcriptional states could both contribute to platinum resistance. The dominance of genomic or non-genomic mechanisms within polyclonal tumors has implications for drug sensitivity, restoration, and re-treatment strategies.

CYR61 confers chemoresistance by upregulating survivin expression in triple-negative breast cancer

Cysteine-rich angiogenic inducer 61 (CYR61) is a protein from the CCN family of matricellular proteins that play diverse regulatory roles in the extracellular matrix. CYR61 is involved in cell adhesion, migration, proliferation, differentiation, apoptosis, and senescence. Here, we show that CYR61 induces chemoresistance in triple-negative breast cancer (TNBC). We observed that CYR61 is overexpressed in TNBC patients, and CYR61 expression correlates negatively with the survival of patients who receive chemotherapy. CYR61 knockdown reduced cell migration, sphere formation and the cancer stem cell (CSC) population and increased the chemosensitivity of TNBC cells. Mechanistically, CYR61 activated Wnt/β-catenin signaling and increased survivin expression, which are associated with chemoresistance, the epithelial-mesenchymal transition, and CSC-like phenotypes. Altogether, our study demonstrates a novel function of CYR61 in chemotherapy resistance in breast cancer.

Global trends in research of nasopharyngeal carcinoma: a bibliometric and visualization analysis

Objective

This study aims to assess the current research status, focus areas, and developmental trends in nasopharyngeal carcinoma (NPC) through a bibliometric analysis.

Methods

Articles focusing on NPC published from 2000 to 2023 were retrieved from the Web of Science database. VOSviewer and CiteSpace were used for bibliometric and visual analysis.

Results

A total of 14516 related publications were retrieved. There has been a steady increase in the number of NPC-related publications from 2000 to 2023. China was the dominant country in this field with 8948 papers (61.64%), followed by the USA (2234, 15.39%). Sun Yat-sen University was the most influential institution, while Ma J was the most prolific author. Furthermore, Head And Neck-journal For The Sciences And Specialties Of The Head And Neck was the most prolific journal. International Journal of Radiation Oncology Biology Physics had the highest total citation counts. "Introduction chemotherapy", "Concurrent chemotherapy", "Epithelial-mesenchymal transition", "Cancer stem cells", "MicroRNAs", "LncRNA", "Exosomes", and "Biomarker" were the most common keywords. The reference "Chen YP, 2019, Lancet" had the highest citations and strong outbreak value.

Conclusion

The past two decades have witnessed a significant increase in research on NPC. The optimization of treatment mode is the most widely studied aspect at present. The mechanism of occurrence and development and the most favorable diagnostic and therapeutic targets are the research hotspots in the future.

Overcoming Resistance to Standard-of-Care Therapies for Head and Neck Squamous Cell Carcinomas

Although there have been some advances during in recent decades, the treatment of head and neck squamous cell carcinoma (HNSCC) remains challenging. Resistance is a major issue for various treatments that are used, including both the conventional standards of care (radiotherapy and platinum-based chemotherapy) and the newer EGFR and checkpoint inhibitors. In fact, all the non-surgical treatments currently used for HNSCC are associated with intrinsic and/or acquired resistance. Herein, we explore the cellular mechanisms of resistance reported in HNSCC, including those related to epigenetic factors, DNA repair defects, and several signaling pathways. This article discusses these mechanisms and possible approaches that can be used to target different pathways to sensitize HNSCC to the existing treatments, obtain better responses to new agents, and ultimately improve the patient outcomes.

NANOS1 restricts oral cancer cell motility and TGF-ß signaling

Oral squamous cell carcinoma (OSCC) is the most frequent type of cancer of the head and neck area accounting for approx. 377,000 new cancer cases every year. The epithelial-to-mesenchymal transition (EMT) program plays an important role in OSCC progression and metastasis therefore contributing to a poor prognosis in patients with advanced disease. Transforming growth factor beta (TGF-ß) is a powerful inducer of EMT thereby increasing cancer cell aggressiveness. Here, we aimed at identifying RNA-binding proteins (RBPs) that affect TGF-ß-induced EMT. To this end we treated oral cancer cells with TGF-ß and identified a total of 643 significantly deregulated protein-coding genes in response to TGF-ß. Of note, 19 genes encoded RBPs with NANOS1 being the most downregulated RBP. Subsequent cellular studies demonstrated a strong inhibitory effect of NANOS1 on migration and invasion of SAS oral cancer cells. Further mechanistic studies revealed an interaction of NANOS1 with the TGF-ß receptor 1 (TGFBR1) mRNA, leading to increased decay of this transcript and a reduced TGFBR1 protein expression, thereby preventing downstream TGF-ß/SMAD signaling. In summary, we identified NANOS1 as negative regulator of TGF-ß signaling in oral cancer cells.

Carbamate compounds induced toxic effects by affecting Nrf2 signaling pathways

Carbamate (CBs) is a class of insecticides which is being known as an important cause of intentional or accidental poisoning. CBs, cause carbamylation of acetylcholinesterase at neuronal synapses and neuromuscular junction. Exposure to CBs through skin contact, inhalation, or ingestion can result in significant cholinergic toxicity. This is due to the elevation of acetylcholine levels at ganglionic synapses found in both the sympathetic and parasympathetic nervous systems, as well as muscarinic receptors located in target organs of the parasympathetic nervous system, nicotinic receptors situated in skeletal muscle tissue, and the central nervous system. The association between human illnesses and environmental exposures to CBs have been extensively studied in several studies. Although CBs-triggered toxicity leads to overproduction of reactive oxygen species (ROS), the detailed association between the toxicity under CBs exposure and NFE2-related factor 2 (Nrf2) signaling pathways has not been completely clarified. In this review we aimed to summarize the latest findings on the functional interrelationship between carbamates compounds and Nrf2 signaling.

Suppression of lysosome metabolism-meditated GARP/TGF-β1 complexes specifically depletes regulatory T cells to inhibit breast cancer metastasis

Regulatory T cells (Tregs) prevent autoimmunity and contribute to cancer progression. They exert contact-dependent inhibition of immune cells through the production of active transforming growth factor-β1 (TGF-β1). However, the absence of a specific surface marker makes inhibiting the production of active TGF-β1 to specifically deplete human Tregs but not other cell types a challenge. TGF-β1 in an inactive form binds to Tregs membrane protein Glycoprotein A Repetitions Predominant (GARP) and then activates it via an unknown mechanism. Here, we demonstrated that tumour necrosis factor receptor-associated factor 3 interacting protein 3 (TRAF3IP3) in the Treg lysosome is involved in this activation mechanism. Using a novel naphthalenelactam-platinum-based anticancer drug (NPt), we developed a new synergistic effect by suppressing ATP-binding cassette subfamily B member 9 (ABCB9) and TRAF3IP3-mediated divergent lysosomal metabolic programs in tumors and human Tregs to block the production of active GARP/TGF-β1 for remodeling the tumor microenvironment. Mechanistically, NPt is stored in Treg lysosome to inhibit TRAF3IP3-meditated GARP/TGF-β1 complex activation to specifically deplete Tregs. In addition, by promoting the expression of ABCB9 in lysosome membrane, NPt inhibits SARA/p-SMAD2/3 through CHRD-induced TGF-β1 signaling pathway. In addition to expose a previously undefined divergent lysosomal metabolic program-meditated GARP/TGF-β1 complex blockade by exploring the inherent metabolic plasticity, NPt may serve as a therapeutic tool to boost unrecognized Treg-based immune responses to infection or cancer via a mechanism distinct from traditional platinum drugs and currently available immune-modulatory antibodies.

Single dual-specific anti-PD-L1/TGF-β antibody synergizes with chemotherapy as neoadjuvant treatment for pancreatic ductal adenocarcinoma: a preclinical experimental study

AIMS

Chemotherapy resistance is an important cause of neoadjuvant therapy failure in pancreatic ductal adenocarcinoma (PDAC). BiTP (anti-PD-L1/TGF-β bispecific antibody) is a single antibody that can simultaneously and dually target transforming growth factor-beta (TGF-β) and programmed cell death ligand 1 (PD-L1). We attempted in this study to investigate the efficacy of BiTP in combination with first-line chemotherapy in PDAC.

METHODS

Preclinical assessments of BiTP plus gemcitabine and nab-paclitaxel were completed through a resectable KPC mouse model (C57BL/6J). Spectral flow cytometry, tissue section staining, enzyme-linked immunosorbent assays, Counting Kit-8, transwell, and Western blot assays were used to investigate the synergistic effects.

RESULTS

BiTP combinatorial chemotherapy in neoadjuvant settings significantly downstaged PDAC tumors, enhanced survival, and had a higher resectability for mice with PDAC. BiTP was high affinity binding to targets and reverse chemotherapy resistance of PDAC cells. The combination overcame immune evasion through reprogramming tumor microenvironment via increasing penetration and function of T cells, natural killer cells, and dendritic cells and decreasing the function of immunosuppression-related cells as regulatory T cells, M2 macrophages, myeloid-derived suppressor cells, and cancer-associated fibroblasts.

CONCLUSION

Our results suggest that the BiTP combinatorial chemotherapy is a promising neoadjuvant therapy for PDAC.

Beyond genetics: driving cancer with the tumour microenvironment behind the wheel

Cancer has long been viewed as a genetic disease of cumulative mutations. This notion is fuelled by studies showing that ageing tissues are often riddled with clones of complex oncogenic backgrounds coexisting in seeming harmony with their normal tissue counterparts. Equally puzzling, however, is how cancer cells harbouring high mutational burden contribute to normal, tumour-free mice when allowed to develop within the confines of healthy embryos. Conversely, recent evidence suggests that adult tissue cells expressing only one or a few oncogenes can, in some contexts, generate tumours exhibiting many of the features of a malignant, invasive cancer. These disparate observations are difficult to reconcile without invoking environmental cues triggering epigenetic changes that can either dampen or drive malignant transformation. In this Review, we focus on how certain oncogenes can launch a two-way dialogue of miscommunication between a stem cell and its environment that can rewire downstream events non-genetically and skew the morphogenetic course of the tissue. We review the cells and molecules of and the physical forces acting in the resulting tumour microenvironments that can profoundly affect the behaviours of transformed cells. Finally, we discuss possible explanations for the remarkable diversity in the relative importance of mutational burden versus tumour microenvironment and its clinical relevance.

METTL3-mediated ALDH m6A methylation regulates the malignant behavior of BMI1+ HNSCC stem cells

OBJECTIVES

To reveal the effect and mechanism of methyltransferase-like 3 (METTL3) on cancer stem cells (CSCs) of head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

First, we analyzed 14-HNSCC-patients' scRNA-seq dataset and TCGA dataset of HNSCC. Then, Mettl3 knockout or overexpression mice models were studied via tracing and staining technologies. In addition, we took flow cytometry sorting and sphere formation assays to observe tumorigenicity and used cell transfection and western blotting to verify target protein expression levels. Furthermore, methylated RNA immunoprecipitation sequencing (MeRIP-seq) and MeRIP-quantitative real-time PCR (MeRIP-qPCR) were taken to identify the mechanism of Mettl3 regulating Bmi1+ CSCs in HNSCC.

RESULTS

Due to SOX4 transcriptional regulation, METTL3 regulated the malignant behavior of BMI1+ HNSCC stem cells through cell division pathway. The progression and malignancy of HNSCC were decreased after Mettl3 knocked-out, while increased after Mettl3 knocked-in in Bmi1+ CSCs in vivo. Knockdown of Mettl3 inhibited stemness properties of CSCs in vitro. Mechanically, Mettl3 mediated the m6A modification of ALDH1A3 and ALDH7A1 mRNA in Bmi1+ HNSCC CSCs.

CONCLUSION

Regulated by SOX4, METTL3-mediated ALDH m6A methylation regulates the malignant behavior of BMI1+ HNSCC CSCs through cell division pathway.

SMAD4 endows TGF-β1-induced highly invasive tumor cells with ferroptosis vulnerability in pancreatic cancer

Pancreatic ductal adenocarcinoma (PDAC) is an extremely aggressive malignancy prone to recurrence and metastasis. Studies show that tumor cells with increased invasive and metastatic potential are more likely to undergo ferroptosis. SMAD4 is a critical molecule in the transforming growth factor β (TGF-β) pathway, which affects the TGF-β-induced epithelial-mesenchymal transition (EMT) status. SMAD4 loss is observed in more than half of patients with PDAC. In this study, we investigated whether SMAD4-positive PDAC cells were prone to ferroptosis because of their high invasiveness. We showed that SMAD4 status almost determined the orientation of transforming growth factor β1 (TGF-β1)-induced EMT via the SMAD4-dependent canonical pathway in PDAC, which altered ferroptosis vulnerability. We identified glutathione peroxidase 4 (GPX4), which inhibited ferroptosis, as a SMAD4 down-regulated gene by RNA sequencing. We found that SMAD4 bound to the promoter of GPX4 and decreased GPX4 transcription in PDAC. Furthermore, TGF-β1-induced high invasiveness enhanced sensitivity of SMAD4-positive organoids and pancreas xenograft models to the ferroptosis inducer RAS-selective lethal 3 (RSL3). Moreover, SMAD4 enhanced the cytotoxic effect of gemcitabine combined with RSL3 in highly invasive PDAC cells. This study provides new ideas for the treatment of PDAC, especially SMAD4-positive PDAC.

The roles and mechanisms of TGFB1 in acute myeloid leukemia chemoresistance

Relapsed or Refractory (R/R) Acute Myeloid Leukemia (AML) patients usually have very poor prognoses, and drug-resistance is one of the major limiting factors. In this study, we aimed to explore the functions of Transforming Growth Factor-β1 (TGFB1) in AML drug-resistance. First, TGFB1 levels in serum and bone marrow are higher in R/R patients compared with newly diagnosed patients, this phenomenon could be due to different sources of secreted TGFB1 according to immunohistochemistry of marrow biopsies. Similarly, TGFB1 expression in AML drug-resistant cell lines is higher than that in their parental cell lines, and blocking the TGFB signaling pathway by specific inhibitors decreased resistance to chemotherapeutic agents. On the other hand, exogenous TGFB1 can also promote AML parental cells senescence and chemotherapy resistance. Next, we found SOX4 level is upregulated in drug-resistant cells, and parental cells treated with exogenous TGFB1 induced upregulation of SOX4 levels. Interference of SOX4 expression by siRNA diminished the TGFB1-induced sensitivity to chemotherapeutic agents. Finally, we conduct metabolomic analysis and find Alanine, aspartate and glutamate metabolism pathway, and Glycerophospholipid metabolism pathway are decreased after inhibiting TGFB signaling pathway or interfering SOX4 expression. This study concludes that TGFB1 level in R/R AML patients and drug-resistant strains is significantly increased. Blocking the TGFB signaling pathway can enhance the chemosensitivity of drug-resistant cells by suppressing SOX4 expression and metabolic reprogramming.

Transcription Factors and Markers Related to Epithelial-Mesenchymal Transition and Their Role in Resistance to Therapies in Head and Neck Cancers

Head and neck cancers (HNCs) are heterogeneous and aggressive tumors of the upper aerodigestive tract. Although various histological types exist, the most common is squamous cell carcinoma (HNSCC). The incidence of HNSCC is increasing, making it an important public health concern. Tumor resistance to contemporary treatments, namely, chemo- and radiotherapy, and the recurrence of the primary tumor after its surgical removal cause huge problems for patients. Despite recent improvements in these treatments, the 5-year survival rate is still relatively low. HNSCCs may develop local lymph node metastases and, in the most advanced cases, also distant metastases. A key process associated with tumor progression and metastasis is epithelial-mesenchymal transition (EMT), when poorly motile epithelial tumor cells acquire motile mesenchymal characteristics. These transition cells can invade different adjacent tissues and finally form metastases. EMT is governed by various transcription factors, including the best-characterized TWIST1 and TWIST2, SNAIL, SLUG, ZEB1, and ZEB2. Here, we highlight the current knowledge of the process of EMT in HNSCC and present the main protein markers associated with it. This review focuses on the transcription factors related to EMT and emphasizes their role in the resistance of HNSCC to current chemo- and radiotherapies. Understanding the role of EMT and the precise molecular mechanisms involved in this process may help with the development of novel anti-cancer therapies for this type of tumor.

Harnessing function of EMT in cancer drug resistance: a metastasis regulator determines chemotherapy response

Epithelial-mesenchymal transition (EMT) is a complicated molecular process that governs cellular shape and function changes throughout tissue development and embryogenesis. In addition, EMT contributes to the development and spread of tumors. Expanding and degrading the surrounding microenvironment, cells undergoing EMT move away from the main location. On the basis of the expression of fibroblast-specific protein-1 (FSP1), fibroblast growth factor (FGF), collagen, and smooth muscle actin (-SMA), the mesenchymal phenotype exhibited in fibroblasts is crucial for promoting EMT. While EMT is not entirely reliant on its regulators like ZEB1/2, Twist, and Snail proteins, investigation of upstream signaling (like EGF, TGF-β, Wnt) is required to get a more thorough understanding of tumor EMT. Throughout numerous cancers, connections between tumor epithelial and fibroblast cells that influence tumor growth have been found. The significance of cellular crosstalk stems from the fact that these events affect therapeutic response and disease prognosis. This study examines how classical EMT signals emanating from various cancer cells interfere to tumor metastasis, treatment resistance, and tumor recurrence.

Metabolomic machine learning predictor for diagnosis and prognosis of gastric cancer

Gastric cancer (GC) represents a significant burden of cancer-related mortality worldwide, underscoring an urgent need for the development of early detection strategies and precise postoperative interventions. However, the identification of non-invasive biomarkers for early diagnosis and patient risk stratification remains underexplored. Here, we conduct a targeted metabolomics analysis of 702 plasma samples from multi-center participants to elucidate the GC metabolic reprogramming. Our machine learning analysis reveals a 10-metabolite GC diagnostic model, which is validated in an external test set with a sensitivity of 0.905, outperforming conventional methods leveraging cancer protein markers (sensitivity < 0.40). Additionally, our machine learning-derived prognostic model demonstrates superior performance to traditional models utilizing clinical parameters and effectively stratifies patients into different risk groups to guide precision interventions. Collectively, our findings reveal the metabolic landscape of GC and identify two distinct biomarker panels that enable early detection and prognosis prediction respectively, thus facilitating precision medicine in GC.

Diverse temporal and spatial mechanisms work, partially through Stanniocalcin-1, V-ATPase and senescence, to activate the extracellular ATP-mediated drug resistance in human cancer cells

Introduction

Resistance to drug therapies is associated with a large majority of cancer-related deaths. ATP-binding cassette (ABC) transporter-mediated drug efflux, epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs), glutathione (GSH), senescence, and vacuole-type ATPase (V-ATPase) all contribute to the resistance. We recently showed that extracellular ATP (eATP) induces and regulates EMT, CSC formation, and ABC transporters in human cancer cells and tumors. eATP also consistently upregulates Stanniocalcin-1 (STC1), a gene that significantly contributes to EMT, CSC formation, and tumor growth. We also found that eATP enhances drug resistance in cancer cells through eATP internalization mediated by macropinocytosis, leading to an elevation of intracellular ATP (iATP) levels, induction of EMT, and CSC formation. However, these factors have never been systematically investigated in the context of eATP-induced drug resistance.

Methods

In this study, we hypothesized that eATP increases drug resistance via inducing ABC efflux, EMT, CSCs, STC1, and their accompanied processes such as GSH reducing activity, senescence, and V-ATPase. RNA sequencing, metabolomics, gene knockdown and knockout, and functional assays were performed to investigate these pathways and processes.

Results and discussion

Our study results showed that, in multiple human cancer lines, eATP induced genes involved in drug resistance, elevated ABC transporters' efflux activity of anticancer drugs; generated transcriptomic and metabolic profiles representing a drug resistant state; upregulated activities of GSH, senescence, and V-ATPase to promote drug resistance. Collectively, these newly found players shed light on the mechanisms of eATP-induced as well as STC1- and V-ATPase-mediated drug resistance and offer potential novel targets for combating drug resistance in cancers.

Multifaceted TGF-β signaling, a master regulator: From bench-to-bedside, intricacies, and complexities

Physiological embryogenesis and adult tissue homeostasis are regulated by transforming growth factor-β (TGF-β), an evolutionarily conserved family of secreted polypeptide factors, acting in an autocrine and paracrine manner. The role of TGF-β in inflammation, fibrosis, and cancer is complex and sometimes even contradictory, exhibiting either inhibitory or promoting effects depending on the stage of the disease. Under pathological conditions, especially fibrosis and cancer, overexpressed TGF-β causes extracellular matrix deposition, epithelial-mesenchymal transition, cancer-associated fibroblast formation, and/or angiogenesis. In this review article, we have tried to dive deep into the mechanism of action of TGF-β in inflammation, fibrosis, and carcinogenesis. As TGF-β and its downstream signaling mechanism are implicated in fibrosis and carcinogenesis blocking this signaling mechanism appears to be a promising avenue. However, targeting TGF-β carries substantial risk as this pathway is implicated in multiple homeostatic processes and is also known to have tumor-suppressor functions. There is a need for careful dosing of TGF-β drugs for therapeutic use and patient selection.

Nasopharyngeal carcinoma: current views on the tumor microenvironment's impact on drug resistance and clinical outcomes

The incidence of nasopharyngeal carcinoma (NPC) exhibits significant variations across different ethnic groups and geographical regions, with Southeast Asia and North Africa being endemic areas. Of note, Epstein-Barr virus (EBV) infection is closely associated with almost all of the undifferentiated NPC cases. Over the past three decades, radiation therapy and chemotherapy have formed the cornerstone of NPC treatment. However, recent advancements in immunotherapy have introduced a range of promising approaches for managing NPC. In light of these developments, it has become evident that a deeper understanding of the tumor microenvironment (TME) is crucial. The TME serves a dual function, acting as a promoter of tumorigenesis while also orchestrating immunosuppression, thereby facilitating cancer progression and enabling immune evasion. Consequently, a comprehensive comprehension of the TME and its intricate involvement in the initiation, progression, and metastasis of NPC is imperative for the development of effective anticancer drugs. Moreover, given the complexity of TME and the inter-patient heterogeneity, personalized treatment should be designed to maximize therapeutic efficacy and circumvent drug resistance. This review aims to provide an in-depth exploration of the TME within the context of EBV-induced NPC, with a particular emphasis on its pivotal role in regulating intercellular communication and shaping treatment responses. Additionally, the review offers a concise summary of drug resistance mechanisms and potential strategies for their reversal, specifically in relation to chemoradiation therapy, targeted therapy, and immunotherapy. Furthermore, recent advances in clinical trials pertaining to NPC are also discussed.

Transforming Growth Factor-β/Smad Signaling Inhibits Melanoma Cancer Stem Cell Self-Renewal, Tumor Formation and Metastasis

The secreted protein transforming growth factor-beta (TGFβ) plays essential roles, ranging from cell growth regulation and cell differentiation in both normal and cancer cells. In melanoma, TGFβ acts as a potent tumor suppressor in melanoma by blocking cell cycle progression and inducing apoptosis. In the present study, we found TGFβ to regulate cancer stemness in melanoma through the Smad signaling pathway. We discovered that TGFβ/Smad signaling inhibits melanosphere formation in multiple melanoma cell lines and reduces expression of the CD133+ cancer stem cell subpopulation in a Smad3-dependent manner. Using preclinical models of melanoma, we further showed that preventing Smad3/4 signaling, by means of CRISPR knockouts, promoted both tumorigenesis and lung metastasis in vivo. Collectively, our results define new functions for the TGFβ/Smad signaling axis in melanoma stem-cell maintenance and open avenues for new therapeutic approaches to this disease.

Activation of the TGF-β1/EMT signaling pathway by claudin-1 overexpression reduces doxorubicin sensitivity in small cell lung cancer SBC-3 cells

Small-cell lung cancer (SCLC), which accounts for about 15 % of all lung cancers, progresses more rapidly than other histologic types and is rarely detected at an operable early stage. Therefore, chemotherapy, radiation therapy, or their combination are the primary treatments for this type of lung cancer. However, the tendency to acquire resistance to anticancer drugs is a severe problem. Recently, we found that an intercellular adhesion molecule, claudin (CLDN) 1, known to be involved in the migration and invasion of lung cancer cells, is involved in the acquisition of anticancer drug resistance. In the present study, we investigated the effect of CLDN1 on the anticancer-drug sensitivity of SCLC SBC-3 cells. Since epithelial-mesenchymal transition (EMT), which is involved in cancer cell migration and invasion, is well known for its involvement in anticancer-drug sensitivity via inhibition of apoptosis, we also examined EMT involvement in decreased anticancer-drug sensitivity by CLDN1. Sensitivity to doxorubicin (DOX) in SBC-3 cells was significantly decreased by CLDN1 overexpression. CLDN1 overexpression resulted in increased TGF-β1 levels, enhanced EMT induction, and increased migratory potency of SBC-3 cells. The decreased sensitivity of SBC-3 cells to anticancer drugs upon TGF-β1 treatment suggested that activation of the TGF-β1/EMT signaling pathway by CLDN1 causes the decreased sensitivity to anticancer drugs and increased migratory potency. Furthermore, treatments with antiallergic agents tranilast and zoledronic acid, known EMT inhibitors, significantly mitigated the decreased sensitivity of CLDN1-overexpressing SBC-3 cells to DOX. These results suggest that EMT inhibitors might effectively overcome reduced sensitivity to anticancer drugs in CLDN1-overexpressing SCLC cells.

Progress of Cancer Stem Cells in Retinoblastoma

The theory of cancer stem cells is a breakthrough discovery that offers exciting possibilities for comprehending the biological behavior of tumors. More and more evidence suggests that retinoblastoma cancer stem cells promote tumor growth and are likely to be the origin of tumor formation, drug resistance, recurrence, and metastasis. At present, some progress has been made in the verification, biological behavior, and drug resistance mechanism of retinoblastoma cancer stem cells. This article aims to review the relevant research and explore future development direction.

Panoramic view of key cross-talks underpinning the oral squamous cell carcinoma stemness - unearthing the future opportunities

The clinical management of oral cancer is often frequented with challenges that arise from relapse, recurrence, invasion and resistance towards the cornerstone chemo and radiation therapies. The recent conceptual advancement in oncology has substantiated the role of cancer stem cells (CSC) as a predominant player of these intricacies. CSC are a sub-group of tumor population with inherent adroitness to self-renew with high plasticity. During tumor evolution, the structural and functional reprogramming persuades the cancer cells to acquire stem-cell like properties, thus presenting them with higher survival abilities and treatment resistance. An appraisal on key features that govern the stemness is of prime importance to confront the current challenges encountered in oral cancer. The nurturing niche of CSC for maintaining its stemness characteristics is thought to be modulated by complex multi-layered components encompassing neoplastic cells, extracellular matrix, acellular components, circulatory vessels, various cascading signaling molecules and stromal cells. This review focuses on recapitulating both intrinsic and extrinsic mechanisms that impart the stemness. There are contemplating evidences that demonstrate the role of transcription factors (TF) in sustaining the neoplastic stem cell's pluripotency and plasticity alongside the miRNA in regulation of crucial genes involved in the transformation of normal oral mucosa to malignancy. This review illustrates the interplay between miRNA and various known TF of oral cancer such as c-Myc, SOX, STAT, NANOG and OCT in orchestrating the stemness and resistance features. Further, the cross-talks involved in tumor micro-environment inclusive of cytokines, macrophages, extra cellular matrix, angiogenesis leading pathways and influential factors of hypoxia on tumorigenesis and CSC survival have been elucidated. Finally, external factorial influence of oral microbiome gained due to the dysbiosis is also emphasized. There are growing confirmations of the possible roles of microbiomes in the progression of oral cancer. Given this, an attempt has been made to explore the potential links including EMT and signaling pathways towards resistance and stemness. This review provides a spectrum of understanding on stemness and progression of oral cancers at various regulatory levels along with their current therapeutic knowledge. These mechanisms could be exploited for future research to expand potential treatment strategies.

A PERK-Specific Inhibitor Blocks Metastatic Progression by Limiting Integrated Stress Response-Dependent Survival of Quiescent Cancer Cells

PURPOSE

The integrated stress response (ISR) kinase PERK serves as a survival factor for both proliferative and dormant cancer cells. We aim to validate PERK inhibition as a new strategy to specifically eliminate solitary disseminated cancer cells (DCC) in secondary sites that eventually reawake and originate metastasis.

EXPERIMENTAL DESIGN

A novel clinical-grade PERK inhibitor (HC4) was tested in mouse syngeneic and PDX models that present quiescent/dormant DCCs or growth-arrested cancer cells in micro-metastatic lesions that upregulate ISR.

RESULTS

HC4 significantly blocks metastasis, by killing quiescent/slow-cycling ISRhigh, but not proliferative ISRlow DCCs. HC4 blocked expansion of established micro-metastasis that contained ISRhigh slow-cycling cells. Single-cell gene expression profiling and imaging revealed that a significant proportion of solitary DCCs in lungs were indeed dormant and displayed an unresolved ER stress as revealed by high expression of a PERK-regulated signature. In human breast cancer metastasis biopsies, GADD34 expression (PERK-regulated gene) and quiescence were positively correlated. HC4 effectively eradicated dormant bone marrow DCCs, which usually persist after rounds of therapies. Importantly, treatment with CDK4/6 inhibitors (to force a quiescent state) followed by HC4 further reduced metastatic burden. In HNSCC and HER2+ cancers HC4 caused cell death in dormant DCCs. In HER2+ tumors, PERK inhibition caused killing by reducing HER2 activity because of sub-optimal HER2 trafficking and phosphorylation in response to EGF.

CONCLUSIONS

Our data identify PERK as a unique vulnerability in quiescent or slow-cycling ISRhigh DCCs. The use of PERK inhibitors may allow targeting of pre-existing or therapy-induced growth arrested "persister" cells that escape anti-proliferative therapies.

TGF-β, EMT, and resistance to anti-cancer treatment

Transforming growth factor-β (TGF-β) signaling regulates cell-specific programs involved in embryonic development, wound-healing, and immune homeostasis. Yet, during tumor progression, these TGF-β-mediated programs are altered, leading to epithelial cell plasticity and a reprogramming of epithelial cells into mesenchymal lineages through epithelial-to-mesenchymal transition (EMT), a critical developmental program in morphogenesis and organogenesis. These changes, in turn, lead to enhanced carcinoma cell invasion, metastasis, immune cell differentiation, immune evasion, and chemotherapy resistance. Here, we discuss EMT as one of the critical programs associated with carcinoma cell plasticity and the influence exerted by TGF-β on carcinoma status and function. We further explore the composition of carcinoma and other cell populations within the tumor microenvironment, and consider the relevant outcomes related to the programs associated with cancer treatment resistance.

Localization, tissue biology and T cell state - implications for cancer immunotherapy

Tissue localization is a critical determinant of T cell immunity. CD8+ T cells are contact-dependent killers, which requires them to physically be within the tissue of interest to kill peptide-MHC class I-bearing target cells. Following their migration and extravasation into tissues, T cells receive many extrinsic cues from the local microenvironment, and these signals shape T cell differentiation, fate and function. Because major organ systems are variable in their functions and compositions, they apply disparate pressures on T cells to adapt to the local microenvironment. Additional complexity arises in the context of malignant lesions (either primary or metastatic), and this has made understanding the factors that dictate T cell function and longevity in tumours challenging. Moreover, T cell differentiation state influences how cues from the microenvironment are interpreted by tissue-infiltrating T cells, highlighting the importance of T cell state in the context of tissue biology. Here, we review the intertwined nature of T cell differentiation state, location, survival and function, and explain how dysfunctional T cell populations can adopt features of tissue-resident memory T cells to persist in tumours. Finally, we discuss how these factors have shaped responses to cancer immunotherapy.

NRF3 suppresses squamous carcinogenesis, involving the unfolded protein response regulator HSPA5

Epithelial skin cancers are extremely common, but the mechanisms underlying their malignant progression are still poorly defined. Here, we identify the NRF3 transcription factor as a tumor suppressor in the skin. NRF3 protein expression is strongly downregulated or even absent in invasively growing cancer cells of patients with basal and squamous cell carcinomas (BCC and SCC). NRF3 deficiency promoted malignant conversion of chemically induced skin tumors in immunocompetent mice, clonogenic growth and migration of human SCC cells, their invasiveness in 3D cultures, and xenograft tumor formation. Mechanistically, the tumor-suppressive effect of NRF3 involves HSPA5, a key regulator of the unfolded protein response, which we identified as a potential NRF3 interactor. HSPA5 levels increased in the absence of NRF3, thereby promoting cancer cell survival and migration. Pharmacological inhibition or knock-down of HSPA5 rescued the malignant features of NRF3-deficient SCC cells in vitro and in preclinical mouse models. Together with the strong expression of HSPA5 in NRF3-deficient cancer cells of SCC patients, these results suggest HSPA5 inhibition as a treatment strategy for these malignancies in stratified cancer patients.

Tumor microenvironment diversity and plasticity in cancer multidrug resistance

Multidrug resistance (MDR) poses a significant obstacle to effective cancer treatment, and the tumor microenvironment (TME) is crucial for MDR development and reversal. The TME plays an active role in promoting MDR through several pathways. However, a promising therapeutic approach for battling MDR involves targeting specific elements within the TME. Therefore, this comprehensive review elaborates on the research developments regarding the dual role of the TME in promoting and reversing MDR in cancer. Understanding the complex role of the TME in promoting and reversing MDR is essential to developing effective cancer therapies. Utilizing the adaptability of the TME by targeting novel TME-specific factors, utilizing combination therapies, and employing innovative treatment strategies can potentially combat MDR and achieve personalized treatment outcomes for patients with cancer.

Perivascular niches: critical hubs in cancer evolution

Tumors are heterogeneous ecosystems in which cancer cells coexist within a complex tumor immune microenvironment (TIME). The malignant, stromal, and immune cell compartments establish a plethora of bidirectional cell-cell communication crosstalks that influence tumor growth and metastatic dissemination, which we are only beginning to understand. Cancer cells either co-opt or promote the formation of new blood and lymphatic vessels to cope with their need for nutrients and oxygen. Recent studies have highlighted additional key roles for the tumor vasculature and have identified the perivascular niche as a cellular hub, where intricate and dynamic cellular interactions promote cancer stemness, immune evasion, dormancy, and metastatic spreading. Here, we review these findings, and discuss how they may be exploited therapeutically.

Polysulfide nanoparticles inhibit fibroblast-to-myofibroblast transition via extracellular ROS scavenging and have potential anti-fibrotic properties

This paper is about the effects of reactive oxygen species (ROS) - and of their nanoparticle-mediated extracellular removal - in the TGF-β1-induced differentiation of fibroblasts (human dermal fibroblasts - HDFa) to more contractile myofibroblasts, and in the maintenance of this phenotype. Here, poly(propylene sulfide) (PPS) nanoparticles have been employed on 2D and 3D in vitro models, showing extremely low toxicity and undergoing negligible internalization, thereby ensuring an extracellular-only action. Firstly, PPS nanoparticles abrogated ROS-mediated downstream molecular events such as glutathione oxidation, NF-κB activation, and heme oxidase-1 (HMOX) overexpression. Secondly, PPS nanoparticles were also capable to inhibit, prevent and reverse the TGF-β1-induced upregulation of key biomechanical elements, such as ED-a fibronectin (EF-A FN) and alpha-smooth muscle actin (α-SMA), respectively markers of protomyofibroblastic and of myofibroblastic differentiation. We also confirmed that ROS alone are ineffective promoters of the myofibroblastic transition, although their presence contributes to its stabilization. Finally, the particles also countered TGF-β1-induced matrix- and tissue-level phenomena, e.g., the upregulation of collagen type 1, the development of aberrant collagen type 1/3 ratios and the contracture of HDFa 3D-seeded fibrin constructs. In short, experimental data at molecular, cellular and tissue levels show a significant potential in the use of PPS nanoparticles as anti-fibrotic agents.

TGF-β signaling in health and disease

The TGF-β regulatory system plays crucial roles in the preservation of organismal integrity. TGF-β signaling controls metazoan embryo development, tissue homeostasis, and injury repair through coordinated effects on cell proliferation, phenotypic plasticity, migration, metabolic adaptation, and immune surveillance of multiple cell types in shared ecosystems. Defects of TGF-β signaling, particularly in epithelial cells, tissue fibroblasts, and immune cells, disrupt immune tolerance, promote inflammation, underlie the pathogenesis of fibrosis and cancer, and contribute to the resistance of these diseases to treatment. Here, we review how TGF-β coordinates multicellular response programs in health and disease and how this knowledge can be leveraged to develop treatments for diseases of the TGF-β system.

The Role of Regulatory T Cells in Cancer Treatment Resistance

Despite tremendous progress in cancer treatment in recent years, treatment resistance is still a major challenge for a great number of patients. One of the main causes is regulatory T lymphocytes (Tregs), which suppress excessive inflammatory responses via the secretion of immunosuppressive cytokines and upregulate the immune checkpoints. Their abundance causes an immunosuppressive reprogramming of the tumor environment, which is ideal for tumor growth and drug inefficiency. Hence, regiments that can regain tumor immunogenicity are a promising strategy to overcome Tregs-mediated drug resistance. However, to develop effective therapeutic regimens, it is essential to understand the molecular mechanisms of Treg-mediated resistance. In this article, we gathered a comprehensive summary of the current knowledge on molecular mechanisms and the role of Tregs in cancer treatment resistance, including cancer immunotherapy, targeted therapy, chemotherapy, and radiotherapy.

Tumorigenic effects of human mesenchymal stromal cells and fibroblasts on bladder cancer cells

Background

Patients with muscle-invasive bladder cancer face a poor prognosis due to rapid disease progression and chemoresistance. Thus, there is an urgent need for a new therapeutic treatment. The tumor microenvironment (TME) has crucial roles in tumor development, growth, progression, and therapy resistance. TME cells may also survive standard treatment of care and fire up disease recurrence. However, whether specific TME components have tumor-promoting or tumor-inhibitory properties depends on cell type and cancer entity. Thus, a deeper understanding of the interaction mechanisms between the TME and cancer cells is needed to develop new cancer treatment approaches that overcome therapy resistance. Little is known about the function and interaction between mesenchymal stromal cells (MSC) or fibroblasts (FB) as TME components and bladder cancer cells.

Methods

We investigated the functional impact of conditioned media (CM) from primary cultures of different donors of MSC or FB on urothelial carcinoma cell lines (UCC) representing advanced disease stages, namely, BFTC-905, VMCUB-1, and UMUC-3. Underlying mechanisms were identified by RNA sequencing and protein analyses of cancer cells and of conditioned media by oncoarrays.

Results

Both FB- and MSC-CM had tumor-promoting effects on UCC. In some experiments, the impact of MSC-CM was more pronounced. CM augmented the aggressive phenotype of UCC, particularly of those with epithelial phenotype. Proliferation and migratory and invasive capacity were significantly increased; cisplatin sensitivity was reduced. RNA sequencing identified underlying mechanisms and molecules contributing to the observed phenotype changes. NRF2 and NF-κB signaling was affected, contributing to improved cisplatin detoxification. Likewise, interferon type I signaling was downregulated and regulators of epithelial mesenchymal transition (EMT) were increased. Altered protein abundance of CXCR4, hyaluronan receptor CD44, or TGFβ-signaling was induced by CM in cancer cells and may contribute to phenotypical changes. CM contained high levels of CCL2/MCP-1, MMPs, and interleukins which are well known for their impact on other cancer entities.

Conclusions

The CM of two different TME components had overlapping tumor-promoting effects and increased chemoresistance. We identified underlying mechanisms and molecules contributing to the aggressiveness of bladder cancer cells. These need to be further investigated for targeting the TME to improve cancer therapy.

Lymph Vessels Associate with Cancer Stem Cells from Initiation to Malignant Stages of Squamous Cell Carcinoma

Tumor-associated lymph vessels and lymph node involvement are critical staging criteria in several cancers. In skin squamous cell carcinoma, lymph vessels play a role in cancer development and metastatic spread. However, their relationship with the cancer stem cell niche at early tumor stages remains unclear. To address this gap, we studied the lymph vessel localization at the cancer stem cell niche and observed an association from benign skin lesions to malignant stages of skin squamous cell carcinoma. By co-culturing lymphatic endothelial cells with cancer cell lines representing the initiation and promotion stages, and conducting RNA profiling, we observed a reciprocal induction of cell adhesion, immunity regulation, and vessel remodeling genes, suggesting dynamic interactions between lymphatic and cancer cells. Additionally, imaging analyses of the cultured cells revealed the establishment of heterotypic contacts between cancer cells and lymph endothelial cells, potentially contributing to the observed distribution and maintenance at the cancer stem cell niche, inducing downstream cellular responses. Our data provide evidence for an association of lymph vessels from the early stages of skin squamous cell carcinoma development, opening new avenues for better comprehending their involvement in cancer progression.

Polysaccharides from Lentinus edodes prevent acquired drug resistance to docetaxel in prostate cancer cells by decreasing the TGF-β1 secretion of cancer-associated fibroblasts

Prostate cancer is one of the most prevalent lethal diseases among men globally. In the treatment of prostate cancer, the limited therapeutic efficacy of the standard non-hormonal systemic therapy docetaxel (DTX) represents an important challenge. Cancer-associated fibroblasts (CAFs) play a crucial role in resistance to therapy because of their prevalence and functional pleiotropy in tumor environments. Our previous research revealed that MPSSS, a novel polysaccharide extracted from Lentinus edodes, could significantly attenuate the immunosuppressive function of myeloid suppressor cells and CAFs. In this study, we investigated whether MPSSS could potentiate the efficacy of DTX against prostate cancer by inhibiting CAF-induced chemoresistance and elucidated its underlying mechanisms. The sensitivity of PC-3 prostate cancer cells cultured with conditioned medium derived from CAFs (CAF-CM) to DTX was assessed. The resistance effect induced by CAF-CM was abolished when CAFs were pretreated with MPSSS. Bioinformatic analysis of datasets from the Gene Expression Omnibus database revealed the activation of the transforming growth factor β1 (TGF-β1) signaling pathway in DTX-resistant cells. Based on this finding, we demonstrated that treatment with the TGF-β1 receptor inhibitor SB525334 reversed DTX resistance in CAFs, suggesting that TGF-β1 secreted by CAFs was a crucial intermediary in the development of DTX resistance in PC3 cells. Further research revealed that MPSSS decreases the secretion of TGF-β1 by inhibiting the JAK2/STAT3 pathway via Toll-like receptor 4 in CAFs. Overall, MPSSS might be a potential adjuvant treatment for DTX resistance in prostate cancer.

Comprehensive bioinformatics analysis combined with experimental validation to screen biomarkers for malignant transformation of oral leukoplakia

Oral leukoplakia (OLK) is the most common potentially malignant disorders in the oral cavity. This study aimed to screen the key genes of OLK malignant transformation using the Gene Expression Omnibus (GEO) database and experiments. In this study, the GEO database was employed to screen OLK malignant transformation-related genes, which were subsequently identified with a series of bioinformatic analyses. External validation showed that the model based on LAPTM4B, NR3C1, and COX6A1 had high accuracy in diagnosing OLK malignant transformation. Furthermore, the DMBA-induced potentially malignant disorders and OSCC models in vivo and real-time PCR experiment in vitro further verified the database analysis results. In conclusion, three key genes (LAPTM4B, NR3C1, and COX6A1) were screened as potential biomarkers for the diagnosis and treatment of OLK malignant transformation.

MicroRNAs as the pivotal regulators of cisplatin resistance in head and neck cancers

Although, there is a high rate of good prognosis in early stage head and neck tumors, about half of these tumors are detected in advanced stages with poor prognosis. A combination of chemotherapy, radiotherapy, and surgery is the treatment option in head and neck cancer (HNC) patients. Although, cisplatin (CDDP) as the first-line drug has a significant role in the treatment of HNC patients, CDDP resistance can be observed in a large number of these patients. Therefore, identification of the molecular mechanisms involved in CDDP resistance can help to reduce the side effects and also provides a better therapeutic management. MicroRNAs (miRNAs) as the post-transcriptional regulators play an important role in drug resistance. Therefore, in the present review we investigated the role of miRNAs in CDDP response of head and neck tumors. It has been reported that the miRNAs exerted their roles in CDDP response by regulation of signaling pathways such as WNT, NOTCH, PI3K/AKT, TGF-β, and NF-kB as well as apoptosis, autophagy, and EMT process. The present review paves the way to suggest a non-invasive miRNA based panel marker for the prediction of CDDP response among HNC patients. Therefore, such diagnostic miRNA based panel marker reduces the CDDP side effects and improves the clinical outcomes of these patients following an efficient therapeutic management.

Targeting the mitochondrial calcium uniporter inhibits cancer progression and alleviates cisplatin resistance in esophageal squamous cell carcinoma

Cisplatin is the standard chemotherapeutic drug used for the treatment of esophageal squamous cell carcinoma (ESCC). Acquired cisplatin resistance is the primary obstacle to prolonging patient survival time. Here, the therapeutic effects of mitochondrial calcium uniporter (MCU) inhibition on tumor growth and cisplatin resistance in ESCC were assessed. MCU was stably overexpressed or knocked down in three ESCC cell lines and three cisplatin‑resistant ESCC cell lines. Then, proliferation, migration, and mitochondrial membrane potential (MMP) were measured by colony formation, wound healing, Transwell, and JC‑1 staining assays. MCU, MICU2, MICU1, and PD‑L1 levels were detected through western blotting and immunofluorescence. ESCC and cisplatin‑resistant ESCC xenograft mouse models were established. After MCU knockdown, tumor volume was measured. The expression levels of proliferation markers (CyclinD1 and Ki‑67), MICU1/2, PD‑L1, epithelial-mesenchymal transition (EMT) markers (vimentin, β‑catenin, and E‑cadherin), and the angiogenesis marker CD34 were detected through western blotting, immunohistochemistry, or immunofluorescence. The results showed that MCU overexpression significantly promoted proliferation, migration, and MMP in ESCC cells and cisplatin‑resistant ESCC cells. However, proliferation, migration, and MMP were suppressed following MCU knockdown. In ESCC cells, MCU overexpression markedly increased MICU2, MICU1, and PD‑L1 levels, and the opposite results were observed when MCU was stably knocked down. Similarly, MCU inhibition decreased MICU2, MICU1, and PD‑L1 expression in cisplatin‑resistant ESCC cells. Moreover, MCU knockdown substantially decreased tumor growth, EMT, and angiogenesis in ESCC and cisplatin‑resistant ESCC xenograft mice. Collectively, targeting MCU may inhibit cancer progression and alleviate cisplatin resistance in ESCC.