Insights into Melanoma Fibroblast Populations and Therapeutic Strategy Perspectives: Friends or Foes?

Cross-Talk Between Cancer and Its Cellular Environment-A Role in Cancer Progression

The tumor microenvironment is a dynamic and complex three-dimensional network comprising the extracellular matrix and diverse non-cancerous cells, including fibroblasts, adipocytes, endothelial cells and various immune cells (lymphocytes T and B, NK cells, dendritic cells, monocytes/macrophages, myeloid-derived suppressor cells, and innate lymphoid cells). A constantly and rapidly growing number of studies highlight the critical role of these cells in shaping cancer survival, metastatic potential and therapy resistance. This review provides a synthesis of current knowledge on the modulating role of the cellular microenvironment in cancer progression and response to treatment.

Smart Ultrasound-responsive Polymers for Drug Delivery: An Overview on Advanced Stimuli-sensitive Materials and Techniques

In recent years, a notable advancement has occurred in the domain of drug delivery systems via the integration of intelligent polymers that respond to ultrasound. The implementation of this groundbreaking methodology has significantly revolutionised the controlled and precise delivery of therapeutic interventions. An in-depth investigation is conducted into the most recent developments in ultrasonic stimulus-responsive materials and techniques for the purpose of accomplishing precise medication administration. The investigation begins with an exhaustive synopsis of the foundational principles underlying drug delivery systems that react to ultrasonic stimuli, focusing specifically on the complex interplay between polymers and ultrasound waves. Significant attention is devoted to the development of polymers that demonstrate tailored responsiveness to ultrasound, thereby exemplifying their versatility in generating controlled drug release patterns. Numerous classifications of intelligent polymers are examined in the discussion, including those that react to variations in temperature, pH, and enzymes. When coupled with ultrasonic stimuli, these polymers offer a sophisticated framework for the precise manipulation of drug release in terms of both temporal and spatial dimensions. The present study aims to examine the synergistic effects of responsive polymers and ultrasound in overcoming biological barriers such as the blood-brain barrier and the gastrointestinal tract. By doing so, it seeks to shed light on the potential applications of these materials in intricate clinical scenarios. The issues and future prospects of intelligent ultrasound-responsive polymers in the context of drug delivery are critically analysed in this article. The objective of this study is to offer valuable perspectives on the challenges that must be overcome to enable the effective implementation of these technologies. The primary objective of this comprehensive review is to furnish researchers, clinicians, and pharmaceutical scientists with a wealth of information that will serve as a guide for forthcoming developments in the development and enhancement of intelligent drug delivery systems that employ ultrasound-responsive polymers to attain superior therapeutic outcomes.

Fabrication of heterocellular spheroids with controllable core-shell structure using inertial focusing effect for scaffold-free 3D cell culture models

Three-dimensional (3D) cell culture models capable of emulating the biological functions of natural tissues are pivotal in tissue engineering and regenerative medicine. Despite progress, the fabrication ofin vitroheterocellular models that mimic the intricate structures of natural tissues remains a significant challenge. In this study, we introduce a novel, scaffold-free approach leveraging the inertial focusing effect in rotating hanging droplets for the reliable production of heterocellular spheroids with controllable core-shell structures. Our method offers precise control over the core-shell spheroid's size and geometry by adjusting the cell suspension density and droplet morphology. We successfully applied this technique to create hair follicle organoids, integrating dermal papilla cells within the core and epidermal cells in the shell, thereby achieving markedly enhanced hair inducibility compared to mixed-structure models. Furthermore, we have developed melanoma tumor spheroids that accurately mimic the dynamic interactions between tumor and stromal cells, showing increased invasion capabilities and altered expressions of cellular adhesion molecules and proteolytic enzymes. These findings underscore the critical role of cellular spatial organization in replicating tissue functionalityin vitro. Our method represents a significant advancement towards generating heterocellular spheroids with well-defined architectures, offering broad implications for biological research and applications in tissue engineering.

Skin Cancer Microenvironment: What We Can Learn from Skin Aging?

Aging is a natural intrinsic process associated with the loss of fibrous tissue, a slower cell turnover, and a reduction in immune system competence. In the skin, the continuous exposition of environmental factors superimposes extrinsic damage, mainly due to ultraviolet radiation causing photoaging. Although not usually considered a pathogenic event, photoaging affects cutaneous biology, increasing the risk of skin carcinogenesis. At the cellular level, aging is typified by the rise of senescence cells a condition characterized by reduced or absent capacity to proliferate and aberrant hyper-secretory activity. Senescence has a double-edged sword in cancer biology given that senescence prevents the uncontrolled proliferation of damaged cells and favors their clearance by paracrine secretion. Nevertheless, the cumulative insults and the poor clearance of injured cells in the elderly increase cancer incidence. However, there are not conclusive data proving that aged skin represents a permissive milieu for tumor onset. On the other hand, tumor cells are capable of activating resident fibroblasts onto a pro-tumorigenic phenotype resembling those of senescent fibroblasts suggesting that aged fibroblasts might facilitate cancer progression. This review discusses changes that occur during aging that can prime neoplasm or increase the aggressiveness of melanoma and non-melanoma skin cancer.

Head-to-Head Comparison of [68Ga]Ga-DOTA.SA.FAPi and [68Ga]Ga-DOTANOC Positron Emission Tomography/Computed Tomography Imaging for the Follow-Up Surveillance of Patients with Medullary Thyroid Cancer

Background: A theranostic probe for accurate staging and treatment is crucial for the management of medullary thyroid cancers (MTCs). The abundance of stroma in most of thyroid cancers, including MTC, opens new avenues for selecting cancer-associated fibroblasts (CAFs) as new molecular imaging and therapeutic targets. [68Ga]Ga-labeled fibroblast activation protein inhibitor (FAPi) molecules have gained importance as alternative molecular imaging agents in the imaging of thyroid cancers. The purpose of this study was to compare the detection efficiency of primary and metastatic lesions of MTCs between [68Ga]Ga-DOTA.SA.FAPi and [68Ga]Ga-DOTANOC positron emission tomography (PET) radiotracers. Materials and Methods: In this retrospective study, [68Ga]Ga-DOTANOC and [68Ga]Ga-DOTA.SA.FAPi PET/CT (computed tomography) images were compared using patient-based and lesion-based analysis in patients with MTC for follow-up assessment. The quantitative assessment included comparing standardized uptake values corrected for lean body mass (SULpeak) and tumor-to-background ratios (TBR). The findings on both scans were validated with the morphological findings of the diagnostic CT. Results: Twenty-seven patients (21 males and 6 females) with a mean age of 42.4 ± 13.2 years (range 14-66 years) were included in the study. [68Ga]Ga-DOTA.SA.FAPi had similar sensitivities as that of [68Ga]Ga-DOTANOC PET/CT for detecting primary tumors (100% [18 of 18] vs. 94.4% [17 of 18], p = 0.979) involved lymph nodes (98.3% [118 of 120] vs. 95% [114 of 120], p = 0.288), and brain metastases (100%). [68Ga]Ga-DOTA.SA.FAPi demonstrated significantly higher sensitivities than [68Ga]Ga-DOTANOC PET/CT for detecting lung nodules (93.5% [87 of 93] vs. 68.9% [64 of 93], p < 0.0001), liver (100% [105 of 105] vs. 46.4% [49 of 105], p < 0.0001), bone (92.4% [110 of 119] vs. 76.5% [91 of 119], p = 0.001), and pleural metastases 98.2% versus 0%. Higher uptake values and TBR values were reported with [68Ga]Ga-DOTA.SA.FAPi compared with that of [68Ga]Ga-DOTANOC. Conclusion: [68Ga]Ga-DOTA.SA.FAPi outperformed [68Ga]Ga-DOTANOC PET/CT in the detection of distant metastases with both patient-based and lesion-based analysis in MTCs.

Thyroid Cancer and Fibroblasts

Thyroid cancer is the most common type of endocrine cancer, and its prevalence continue to rise. Non-metastatic thyroid cancer patients are successfully treated. However, looking for new therapeutic strategies is of great importance for metastatic thyroid cancers that still lead to death. With respect to this, the tumor microenvironment (TME), which plays a key role in tumor progression, should be considered as a new promising therapeutic target to hamper thyroid cancer progression. Indeed, thyroid tumors consist of cancer cells and a heterogeneous and ever-changing niche, represented by the TME, which contributes to establishing most of the features of cancer cells. The TME consists of extracellular matrix (ECM) molecules, soluble factors, metabolites, blood and lymphatic tumor vessels and several stromal cell types that, by interacting with each other and with tumor cells, affect TME remodeling, cancer growth and progression. Among the thyroid TME components, cancer-associated fibroblasts (CAFs) have gained more attention in the last years. Indeed, recent important evidence showed that thyroid CAFs strongly sustain thyroid cancer growth and progression by producing soluble factors and ECM proteins, which, in turn, deeply affect thyroid cancer cell behavior and aggressiveness. Hence, in this article, we describe the thyroid TME, focusing on the desmoplastic stromal reaction, which is a powerful indicator of thyroid cancer progression and an invasive growth pattern. In addition, we discuss the origins and features of the thyroid CAFs, their influence on thyroid cancer growth and progression, their role in remodeling the ECM and their immune-modulating functions. We finally debate therapeutic perspectives targeting CAFs.