Cellular Interactions in the Tumor Microenvironment: The Role of Secretome

Decoding the complex web: cellular and molecular interactions in the lung tumour microenvironment

The lung tumour microenvironment (TME) or stroma is a dynamic space of numerous cells and their released molecules. This complicated web regulates tumour progression and resistance to different modalities. Lung cancer cells in conjunction with their stroma liberate a wide range of factors that dampen antitumor attacks by innate immunity cells like natural killer (NK) cells and also adaptive responses by effector T cells. These factors include numerous growth factors, exosomes and epigenetic regulators, and also anti-inflammatory cytokines. Understanding the intricate interactions between tumour cells and various elements within the lung TME, such as immune and stromal cells can help provide novel strategies for better management and treatment of lung malignancies. The current article discusses the complex network of cells and signalling molecules, which mediate communications in lung TME. By elucidating these multifaceted interactions, we aim to provide insights into potential therapeutic targets and strategies for lung cancer treatment.

Heat shock protein family D member 1 mediates lung cancer cell‑induced angiogenesis of endothelial cells

Angiogenesis is a crucial process in lung cancer growth and progression. Heat shock protein family D member 1 (HSPD1 or HSP60) plays a significant role in promoting lung cancer development, but its role in angiogenesis remains largely unexplored. The present study aimed to investigate the involvement of HSPD1 in lung cancer cell-induced angiogenesis using indirect co-culture experiments. Secretomes were collected from stable HSPD1-knockdown A549 lung cancer cells [short hairpin (sh)HSPD1-A549 cells] and scramble control cells (shControl-A549 cells) and used to treat human endothelial EA.hy926 cells. Effects of the secretomes on key steps of angiogenesis, including endothelial cell proliferation, migration, invasion, aggregation and tube formation, were assessed using BrdU incorporation, wound healing, Transwell invasion, hanging-drop and Matrigel tube formation assays, respectively. The amount of vascular endothelial growth factor (VEGF) secreted by EA.hy926 cells was determined using ELISA. The correlation of VEGFA expression with HSPD1 expression and overall survival in patients with lung adenocarcinoma was evaluated using bioinformatics analysis. The results revealed that the shControl-A549 secretome markedly stimulated endothelial cell proliferation, migration, invasion, aggregation, tube formation and VEGF secretion, whereas the shHSPD1-A549 secretome had no significant effects on these processes. VEGFA expression was markedly associated with HSPD1 expression and overall survival in patients with lung adenocarcinoma. In conclusion, the findings highlighted the role of HSPD1 in promoting angiogenesis capability of endothelial cells, potentially through VEGF-mediated pathways. Targeting HSPD1 may represent a promising therapeutic strategy to inhibit angiogenesis and improve clinical outcomes in lung cancer patients.

Current Understanding of Therapeutic and Diagnostic Applications of Exosomes in Pancreatic Cancer

ABSTRACT

Unusual symptoms, rapid progression, lack of reliable early diagnostic biomarkers, and lack of efficient treatment choices are the ongoing challenges of pancreatic cancer. Numerous research studies have demonstrated the correlation between exosomes and various aspects of pancreatic cancer. In light of these facts, exosomes possess the potential to play functional roles in the treatment, prognosis, and diagnosis of the pancreatic cancer. In the present study, we reviewed the most recent developments in approaches for exosome separation, modification, monitoring, and communication. Moreover, we discussed the clinical uses of exosomes as less invasive liquid biopsies and drug carriers and their contribution to the control of angiogenic activity of pancreatic cancer. Better investigation of exosome biology would help to effectively engineer therapeutic exosomes with certain nucleic acids, proteins, and even exogenous drugs as their cargo. Circulating exosomes have shown promise as reliable candidates for pancreatic cancer early diagnosis and monitoring in high-risk people without clinical cancer manifestation. Although we have tried to reflect the status of exosome applications in the treatment and detection of pancreatic cancer, it is evident that further studies and clinical trials are required before exosomes may be employed as a routine therapeutic and diagnostic tools for pancreatic cancer.

Gastric Cancer Models Developed via GelMA 3D Bioprinting Accurately Mimic Cancer Hallmarks, Tumor Microenvironment Features, and Drug Responses

Current in vitro models for gastric cancer research, such as 2D cell cultures and organoid systems, often fail to replicate the complex extracellular matrix (ECM) found in vivo. For the first time, this study utilizes a gelatin methacryloyl (GelMA) hydrogel, a biomimetic ECM-like material, in 3D bioprinting to construct a physiologically relevant gastric cancer model. GelMA's tunable mechanical properties allow for the precise manipulation of cellular behavior within physiological ranges. Genetic and phenotypic analyses indicate that the 3D bioprinted GelMA (3Db) model accurately mimics the clinical tumor characteristics and reproduces key cancer hallmarks, such as cell proliferation, invasion, migration, angiogenesis, and the Warburg effect. Comparisons of gene expression and drug responses between the 3Db model and patient-derived xenograft models, both constructed from primary gastric cancer cells, validate the model's clinical relevance. The ability of the 3Db model to closely simulate in vivo conditions highlights its crucial role in identifying treatment targets and predicting patient-specific responses, showcasing its potential in high-throughput drug screening and clinical applications. This study is the first to report the pivotal role of GelMA-based 3D bioprinting in advancing gastric cancer research and regenerative medicine.

Evaluation of the Therapeutic Efficacy of Moist Wound Healing After Fractional CO2 Laser Surgery

BACKGROUND

With the popularization of laser therapy, an increasing number of patients are undergoing fractional CO2 laser therapy. It is particularly important to exercise caution and accelerate wound healing after laser surgery.

AIMS

This study aimed to examine the clinical efficacy of moist wound healing after fractional CO2 laser therapy.

PATIENTS/METHODS

A total of 15 individuals volunteered to undergo fractional CO2 laser therapy. The facial skin was irradiated with a fractional CO2 laser in the deep mode, with an energy of 15 mJ/cm2 and a density of 5%. The left and right sides of the faces were considered the observation and control groups, respectively. After laser therapy, medical cold compress patches were applied on the skin in the control group once a day for approximately 10-15 min, whereas erythromycin ophthalmic ointment was applied on the skin in the observation group 6 times daily for wound care. The wound healing time, duration of erythema, and occurrence of adverse reactions were monitored in both groups.

RESULTS

The observation and control groups received different nursing interventions. The time to regression of erythema and swelling was significantly shorter in the observation group than in the control group. In addition, the scab formed at the wound site was thinner, and shedding was faster in the observation group than in the control group. The Clinical Erythema Assessment score of the observation group was significantly lower than that of the control group (p < 0.05). The wound healing time was 5.73 ± 0.70 days in the observation group and 7.73 ± 0.72 days in the control group, with the difference being statistically significant (p < 0.05). After 30 min and 12 h of nursing intervention, the Visual Analog Scale score of the observation group was significantly lower than that of the control group (p < 0.05). However, after 24 h of treatment, neither group showed significant pain. Both groups showed varying degrees of acne, pustules, and exudation, which subsided within 7 days. Furthermore, the control group had 2 cases of mild pigmentation, which resolved within 3 months. Neither group experienced adverse reactions such as skin infection, depigmentation, or scar formation.

CONCLUSION

Moist healing therapy can accelerate wound healing and reduce the duration of erythema and edema after fractional CO2 laser therapy, demonstrating potential clinical application value.

Bioinformatics analysis of PSAT1 loss identifies downstream pathways regulated in EGFR mutant NSCLC and a selective gene signature for predicting the risk of relapse

The majority of malignant tumors exhibit an altered metabolic phenotype that ultimately provides the required energy and molecular precursors necessary for unregulated cell division. Within this, phosphoserine aminotransferase 1 (PSAT1) is involved in de novo serine biosynthesis and its activity promotes various biochemical processes, including one-carbon metabolism. It also directly generates α-ketoglutarate (α-KG), a Kreb cycle intermediate and epigenetic-regulating metabolite. Prior studies examining PSAT1 depletion have identified individual affected downstream pathways, such as GSK3β and E2F, in several cancer types, including non-small-cell lung cancer (NSCLC). However, global gene expression examination in response to PSAT1 loss, particularly in EGFR mutant NSCLC, has not been unexplored. Transcriptional profiling of EGFR mutant NSCLC cells with or without stable knock-down of PSAT1 identified differentially expressed genes (DEGs) enriched in several metabolic pathways required for cell division, including amino acid and nucleotide biosynthesis. Supplementation studies involving non-essential amino acids, nucleosides and α-KG partially restored defects in anchorage-independent growth due to the knockdown of PSAT1. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology enrichment analysis identified potential impacts on actin cytoskeleton arrangement and β-catenin activity, which were rescued by PSAT1 re-expression. Finally, a comparative analysis of PSAT1 DEGs against transcripts enriched in patient EGFR mutant lung tumors identified a gene signature that is associated with overall and relapse-free survival (RFS) and was able to distinguish low or high-risk populations for RFS in early-stage EGFR mutant NSCLC. Overall, investigating genes altered by PSAT1 loss confirmed known PSAT1-regulated cellular pathways, identified a previously unknown role in the mediation of cytoskeleton arrangement in EGFR mutant NSCLC cells and allowed for the characterization of a gene signature with putative predictive potential for RFS in early-stage disease.

A Comprehensive Analysis of Moist Versus Non-Moist Dressings for Split-Thickness Skin Graft Donor Sites: A Systematic Review and Meta-Analysis

Background and Aims

This systematic review and meta-analysis evaluate the efficacy of moist versus non-moist dressings for split-thickness skin graft (STSG) donor sites, focusing on time to healing, pain management, and adverse events to guide clinical practice.

Methods

A comprehensive literature search was conducted across databases including Ovid/MEDLINE, Embase, Cochrane CENTRAL, Cochrane Database of Systematic Reviews, and Scopus up to November 28, 2023. The study adhered to PRISMA guidelines. Eligible randomized controlled trials (RCTs) were assessed for quality using the Newcastle-Ottawa Scale and Cochrane risk-of-bias tool, with meta-analysis performed using the DerSimonian and Laird random-effects model.

Results

Out of 464 identified studies, 16 RCTs involving 1129 patients were included. Moist dressings such as Tegaderm, Hydrocolloid, Alginate, polyurethane, and hydrofiber showed a faster mean time to healing compared to non-moist dressings like Mepitel and paraffin-impregnated gauze. Hydrocolloid dressings were particularly effective in accelerating wound healing. Additionally, moist dressings were associated with lower pain levels during dressing removal and had comparable rates of adverse events.

Conclusion

The evidence strongly supports the use of moist dressings, particularly Hydrocolloid, for STSG donor site coverage. These dressings promote faster healing and superior pain management. The study highlights the need for further research to address existing limitations and refine recommendations for optimal wound care interventions.

Glioblastoma cells alter brain endothelial cell homeostasis and tight junction protein expression in vitro

BACKGROUND

Glioblastoma (GBM) is an aggressive therapy-resistant brain tumour that may impacts the integrity of the blood-brain barrier (BBB). The BBB is a protective barrier of the central nervous system formed mainly by endothelial cells. This study aimed to investigate the in vitro effect of GBM cells on the BBB.

METHODS

Brain endothelial (bEnd.3) cells were used as a model of the BBB. Glioblastoma-conditioned media (CM) was extracted at the 48-h (h) time-point from the U87 GBM cells and diluted to 40% with fresh media. The effect of the U87-CM collected at 48 h on bEnd.3 cell growth was evaluated following 48 and 72 h of treatment using the xCELLigence system. Additionally, bEnd.3 cell growth was also investigated in a U87 and bEnd.3 co-culture model continuously for 48 h using the xCELLigence system. The migration of bEnd.3 cells was assessed following 48 and 72 h using the migration scratch assay. The barrier integrity was evaluated continuously for 1 h using the transwell permeability, and the tight junction (TJ) protein expression was evaluated using Western blot assay following 48 and 72 h.

RESULTS

There was a significant decrease in bEnd.3 cell growth following 32 h (p < 0.05), 40 h (p < 0.01), and 48 h (p < 0.001) of treatment with U87-CM, while co-culturing of bEnd.3 and U87 cells increased cell growth following 16 h (p < 0.05), 24 h (p < 0.001), 32 h (p < 0.01), 40 h (p < 0.001), and 48 h (p < 0.001). The migration of bEnd.3 cells significantly increased following both 24 (p < 0.05) and 48 h (p < 0.01) of treatment with U87-CM. The permeability of bEnd.3 cells co-cultured with U87 for 48 h was significantly increased (p < 0.05) at the 15- and 30-min time points. Furthermore, the expression of ZO-1 and occludin was significantly increased (p < 0.05) in both bEnd.3 cells treated with U87-CM as well as bEnd.3 cells co-cultured with U87 cells.

CONCLUSION

The current findings suggest that U87 cells alter the integrity of bEnd.3 cells possibly through the secretomes in the CM and through cell-cell interactions in co-culture models. This may assist in the understanding of the mechanisms by which GBM affects the BBB, which may aid in the management thereof.

Unlocking the Secrets of Extracellular Vesicles: Orchestrating Tumor Microenvironment Dynamics in Metastasis, Drug Resistance, and Immune Evasion

Extracellular vehicles (EVs) are gaining increasing recognition as central contributors to the intricate landscape of the tumor microenvironment (TME). This manuscript provides an extensive examination of the multifaceted roles played by EVs in shaping the TME, with a particular emphasis on their involvement in metastasis, drug resistance, and immune evasion. Metastasis, the process by which cancer cells disseminate to distant sites, remains a formidable challenge in cancer management. EVs, encompassing exosomes and microvesicles, have emerged as critical participants in this cascade of events. They facilitate the epithelial-to-mesenchymal transition (EMT), foster pre-metastatic niche establishment, and enhance the invasive potential of cancer cells. This manuscript delves into the intricate molecular mechanisms underpinning these processes, underscoring the therapeutic potential of targeting EVs to impede metastasis. Drug resistance represents a persistent impediment to successful cancer treatment. EVs are instrumental in intrinsic and acquired drug resistance, acting as mediators of intercellular communication. They ferry molecules like miRNAs and proteins, which confer resistance to conventional chemotherapy and targeted therapies. This manuscript scrutinizes the diverse strategies employed by EVs in propagating drug resistance while also considering innovative approaches involving EV-based drug delivery systems to counteract this phenomenon. Immune evasion is a hallmark of cancer, and EVs are central in sculpting the immunosuppressive milieu of the TME. Tumor-derived EVs thwart immune responses through various mechanisms, including T cell dysfunction induction, the expansion of regulatory T cells (Tregs), and polarization of macrophages towards an immunosuppressive phenotype. In addition, the manuscript explores the diagnostic potential of EVs as biomarkers and their role as therapeutic agents in immune checkpoint blockade therapies. This manuscript provides a comprehensive overview of EV's pivotal role in mediating intricate interactions within the TME, ultimately influencing cancer progression and therapeutic outcomes. A profound understanding of EV-mediated processes in metastasis, drug resistance, and immune evasion opens up promising avenues for developing innovative therapeutic strategies and identifying valuable biomarkers in the ongoing battle against cancer.

Balancing the Scales: The Dual Role of Interleukins in Bone Metastatic Microenvironments

Bone metastases, a common and debilitating consequence of advanced cancers, involve a complex interplay between malignant cells and the bone microenvironment. Central to this interaction are interleukins (ILs), a group of cytokines with critical roles in immune modulation and inflammation. This review explores the dualistic nature of pro-inflammatory and anti-inflammatory interleukins in bone metastases, emphasizing their molecular mechanisms, pathological impacts, and therapeutic potential. Pro-inflammatory interleukins, such as IL-1, IL-6, and IL-8, have been identified as key drivers in promoting osteoclastogenesis, tumor proliferation, and angiogenesis. These cytokines create a favorable environment for cancer cell survival and bone degradation, contributing to the progression of metastatic lesions. Conversely, anti-inflammatory interleukins, including IL-4, IL-10, and IL-13, exhibit protective roles by modulating immune responses and inhibiting osteoclast activity. Understanding these opposing effects is crucial for developing targeted therapies aimed at disrupting the pathological processes in bone metastases. Key signaling pathways, including NF-κB, JAK/STAT, and MAPK, mediate the actions of these interleukins, influencing tumor cell survival, immune cell recruitment, and bone remodeling. Targeting these pathways presents promising therapeutic avenues. Current treatment strategies, such as the use of denosumab, tocilizumab, and emerging agents like bimekizumab and ANV419, highlight the potential of interleukin-targeted therapies in mitigating bone metastases. However, challenges such as therapeutic resistance, side effects, and long-term efficacy remain significant hurdles. This review also addresses the potential of interleukins as diagnostic and prognostic biomarkers, offering insights into patient stratification and personalized treatment approaches. Interleukins have multifaceted roles that depend on the context, including the environment, cell types, and cellular interactions. Despite substantial progress, gaps in research persist, particularly regarding the precise mechanisms by which interleukins influence the bone metastatic niche and their broader clinical implications. While not exhaustive, this overview underscores the critical roles of interleukins in bone metastases and highlights the need for continued research to fully elucidate their complex interactions and therapeutic potential. Addressing these gaps will be essential for advancing our understanding and treatment of bone metastases in cancer patients.

Cetuximab chemotherapy resistance: Insight into the homeostatic evolution of head and neck cancer (Review)

The complex evolution of genetic alterations in cancer that occurs in vivo is a selective process involving numerous factors and mechanisms. Chemotherapeutic agents that prevent the growth and spread of cancer cells induce selective pressure, leading to rapid artificial selection of resistant subclones. This rapid evolution is possible because antineoplastic drugs promote alterations in tumor‑cell metabolism, thus creating a bottleneck event. The few resistant cells that survive in this new environment obtain differential reproductive success that enables them to pass down the newly selected resistant gene pool. The present review aims to summarize key findings of tumor evolution, epithelial‑mesenchymal transition and resistance to cetuximab therapy in head and neck squamous cell carcinoma.

CD3 and CD20 Expressions and Infiltrating Patterns in Salivary Gland Tumors

Tumor-infiltrating lymphocytes (TILs) represent a subset of immunological constituents within the tumor microenvironment that can influence cancer growth. We retrospectively evaluate the density and pattern of CD3 and CD20 expression in salivary gland tumors and their relation to clinical pathologic parameters. A total of 44 formalin-fixed paraffin-embedded blocks of salivary gland tumors were included. These tumors were stained immunohistochemically with CD3 and CD20. The chi-square test was used to relate immune scoring, intensity, and clinical pathological parameters to different salivary tumors. p-value < 0.05 was considered statistically significant. The intra-tumoral CD3 infiltrating count was high and diffused in (71.4%) of pleomorphic adenomas (PAs) followed by mucoepidermoid carcinomas (MECs) (66.7%). At the same time, adenoid cystic carcinomas (AdCCs) exhibited significantly low infiltration (71.4%) (p = 0.046). The three types of tumors exhibited high tumor-infiltrating counts diffused in peripheral areas with significant differences between malignant tumors (p = 0.047). The intra-tumoral CD20 infiltrating count significantly differed among the tumors (p = 0.002); it was low in all PAs and AdCCs, while MECs showed an equal percentage of expression. However, in the peripheral area, PAs and MECs exhibited significantly (p = 0.007) high infiltrating counts (69.2% and 84.6), and the lowest infiltrating count was predominantly found for AdCCs. The two markers had a significant positive correlation between the mean of CD3 in the intra-tumoral and peripheral regions and CD20 in the peripheral zone across the total samples. In conclusion, the density of CD3 expression is notably higher than CD20 across tumor types. PAs and MECs showed high-density scores, while AdCCs were characterized by low scores. TIL expression was found to be significantly associated with patients' outcomes in the intra-tumoral area.

The secretome from human-derived mesenchymal stem cells augments the activity of antitumor plant extracts in vitro

Cancer is understood as a multifactorial disease that involve multiple cell types and phenotypes in the tumor microenvironment (TME). The components of the TME can interact directly or via soluble factors (cytokines, chemokines, growth factors, extracellular vesicles, etc.). Among the cells composing the TME, mesenchymal stem cells (MSCs) appear as a population with debated properties since it has been seen that they can both promote or attenuate tumor progression. For various authors, the main mechanism of interaction of MSCs is through their secretome, the set of molecules secreted into the extracellular milieu, recruiting, and influencing the behavior of other cells in inflammatory environments where they normally reside, such as wounds and tumors. Natural products have been studied as possible cancer treatments, appealing to synergisms between the molecules in their composition; thus, extracts obtained from Petiveria alliacea (Anamu-SC) and Caesalpinia spinosa (P2Et) have been produced and studied previously on different models, showing promising results. The effect of plant extracts on the MSC secretome has been poorly studied, especially in the context of the TME. Here, we studied the effect of Anamu-SC and P2Et extracts in the human adipose-derived MSC (hAMSC)-tumor cell interaction as a TME model. We also investigated the influence of the hAMSC secretome, in combination with these natural products, on tumor cell hallmarks such as viability, clonogenicity, and migration. In addition, hAMSC gene expression and protein synthesis were evaluated for some key factors in tumor progression in the presence of the extracts by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Multiplex, respectively. It was found that the presence of the hAMSC secretome did not affect the cytotoxic or clonogenicity-reducing activities of the natural extracts on cancer cells, and even this secretome can inhibit the migration of these tumor cells, in addition to the fact that the profile of molecules can be modified by natural products. Overall, our findings demonstrate that hAMSC secretome participation in TME interactions can favor the antitumor activities of natural products.

Filament coating system assists recovery of ablative fCO2 laser treatment: A split-face clinical observation

BACKGROUND

The current nursing procedure after fractional carbon dioxide (fCO2) is complex and needs to be optimized. The present study was conducted to evaluate the assisting effect of filament coating system after fCO2 laser treatment.

METHODS

Chinese individuals aged from 18 to 65 years diagnosed as photoaging or atrophic acne scar were recruited and each participant was treated with one single pass of fCO2 laser. A split face was randomly assigned as treatment side or control side. For control side, conventional procedure was topically applied respectively, including desonide cream two times for 3 days, fusidic acid cream two times for 7 days, and recombinant human epidermal growth factor (RhEGF) gel four times for 7 days; for treating side, a filament coating system was applied immediately after one application of fusidic acid cream, desonide cream and RhEGF, and removed 3 h later, for 3 days. Erythema, edema, crust, and pain on both sides were scored from 0 to 10 before and 1, 2, 4, and 7 days after fCO2 laser treatment. Stratum corneum hydration (SCH) and sebum of forehead and cheek on both sides were also measured by using Corneometer-Sebumeter.

RESULTS

Twenty photoaging and 11 atrophic acne scar participants finished the observation. All of them complained of erythema, edema, crust, and pain after fCO2 laser treatment, and the scores decreased as time passed by. There were no statistical significances of erythema, edema, crust, pain, SCH, and sebum between treating side and control side at each observation time.

CONCLUSION

Filament coating system was effective, safe, convenient, and economic in assisting recovery of ablative fCO2 laser, which might be a new option for additional nursing procedure.

Roles for epithelial integrin α3β1 in regulation of the microenvironment during normal and pathological tissue remodeling

Integrin receptors for the extracellular matrix activate intracellular signaling pathways that are critical for tissue development, homeostasis, and regeneration/repair, and their loss or dysregulation contributes to many developmental defects and tissue pathologies. This review will focus on tissue remodeling roles for integrin α3β1, a receptor for laminins found in the basement membranes (BMs) that underlie epithelial cell layers. As a paradigm, we will discuss literature that supports a role for α3β1 in promoting ability of epidermal keratinocytes to modify their tissue microenvironment during skin development, wound healing, or tumorigenesis. Preclinical and clinical studies have shown that this role depends largely on ability of α3β1 to govern the keratinocyte's repertoire of secreted proteins, or the "secretome," including 1) matrix proteins and proteases involved in matrix remodeling and 2) paracrine-acting growth factors/cytokines that stimulate other cells with important tissue remodeling functions (e.g., endothelial cells, fibroblasts, inflammatory cells). Moreover, α3β1 signaling controls gene expression that helps epithelial cells carry out these functions, including genes that encode secreted matrix proteins, proteases, growth factors, or cytokines. We will review what is known about α3β1-dependent gene regulation through both transcription and posttranscriptional mRNA stability. Regarding the latter, we will discuss examples of α3β1-dependent alternative splicing (AS) or alternative polyadenylation (APA) that prevents inclusion of cis-acting mRNA sequences that would otherwise target the transcript for degradation via nonsense-mediated decay or destabilizing AU-rich elements (AREs) in the 3'-untranslated region (3'-UTR). Finally, we will discuss prospects and anticipated challenges of exploiting α3β1 as a clinical target for the treatment of cancer or wound healing.

Secretome processing for proteomics: A methods comparison

The cancer cell secretome comprises a treasure-trove for biomarkers since it reflects cross-talk between tumor cells and their surrounding environment with high detectability in biofluids. In this study, we evaluated six secretome sample processing workflows coupled to single-shot mass spectrometry: (1) Protein concentration by ultrafiltration with a molecular weight cut-off (MWCO) filter and sample preparation through in-gel digestion (IGD); (2) Acetone protein precipitation coupled to IGD; (3) MWCO filter-based protein concentration followed by to in-solution digestion (ISD); (4) Acetone protein precipitation coupled to ISD; (5) Direct ISD; (6) Secretome lyophilization and ISD. To this end, we assessed workflow triplicates in terms of total number of protein identifications, unique identifications, reproducibility of protein identification and quantification and detectability of small proteins with important functions in cancer biology such as cytokines, chemokines, and growth factors. Our findings revealed that acetone protein precipitation coupled to ISD outperformed the other methods in terms of the number of identified proteins (2246) and method reproducibility (correlation coefficient between replicates (r = 0.94, CV = 19%). Overall, especially small proteins such as those from the classes mentioned above were better identified using ISD workflows. Concluding, herein we report that secretome protein precipitation coupled to ISD is the method of choice for high-throughput secretome proteomics via single shot nanoLC-MS/MS.

New insights into the role of the oral leukoplakia microenvironment in malignant transformation

Oral leukoplakia is the most frequent and potentially malignant lesion of the oral cavity. Although dysplasia grading remains the main factor for risk assessment, challenges persist in determining the exact risk of transformation, and the literature has focused on studying alternative biomarkers. The interaction between dysplastic epithelial cells and the microenvironment starts early, and the communication is mainly mediated by lymphocytes, inflammatory factors, fibroblasts, and the extracellular matrix, leading to dysplastic progression. Leukoplakia-infiltrating leukocytes (LILs) and leukoplakia-associated fibroblasts (LAFs) play crucial roles in the dysplastic microenvironment. The immune response is related to intraepithelial T lymphocyte infiltration, mechanisms of immunosuppression coordinated by regulatory T cells, M2 macrophage polarization, and increased numbers of Langerhans cells; in contrast, fibroblastic and extracellular matrix factors are associated with increased numbers of pro-tumorigenic myofibroblasts, increased expression of metalloproteinases vs. decreased expression of TIMPs, and increased expression of chemokines and other inflammatory mediators. The microenvironment offers insights into the progression of leukoplakia to carcinoma, and understanding the complexity of the oral microenvironment in potentially malignant diseases aids in determining the risk of malignant transformation and proposing new therapeutic alternatives.

Inhibition of CSF-1R and IL-6R prevents conversion of cDC2s into immune incompetent tumor-induced DC3s boosting DC-driven therapy potential

The human dendritic cell (DC) family has recently been expanded by CD1c+CD14+CD163+ DCs, introduced as DC3s. DC3s are found in tumors and peripheral blood of cancer patients. Here, we report elevated frequencies of CD14+ cDC2s, which restore to normal frequencies after tumor resection, in non-small cell lung cancer patients. These CD14+ cDC2s phenotypically resemble DC3s and exhibit increased PD-L1, MERTK, IL-10, and IDO expression, consistent with inferior T cell activation ability compared with CD14- cDC2s. In melanoma patients undergoing CD1c+ DC vaccinations, increased CD1c+CD14+ DC frequencies correlate with reduced survival. We demonstrate conversion of CD5+/-CD1c+CD14- cDC2s to CD14+ cDC2s by tumor-associated factors, whereas monocytes failed to express CD1c under similar conditions. Targeted proteomics identified IL-6 and M-CSF as dominant drivers, and we show that IL-6R and CSF1R inhibition prevents tumor-induced CD14+ cDC2s. Together, this indicates cDC2s as direct pre-cursors of DC3-like CD1c+CD14+ DCs and provides insights into the importance and modulation of CD14+ DC3s in anti-tumor immune responses.

Decoding the Tumour Microenvironment: Molecular Players, Pathways, and Therapeutic Targets in Cancer Treatment

The tumour microenvironment (TME) is a complex and constantly evolving collection of cells and extracellular components. Cancer cells and the surrounding environment influence each other through different types of processes. Characteristics of the TME include abnormal vasculature, altered extracellular matrix, cancer-associated fibroblast and macrophages, immune cells, and secreted factors. Within these components, several molecules and pathways are altered and take part in the support of the tumour. Epigenetic regulation, kinases, phosphatases, metabolic regulators, and hormones are some of the players that influence and contribute to shaping the tumour and the TME. All these characteristics contribute significantly to cancer progression, metastasis, and immune escape, and may be the target for new approaches for cancer treatment.

Tumour response to hypoxia: understanding the hypoxic tumour microenvironment to improve treatment outcome in solid tumours

Hypoxia is a common feature of solid tumours affecting their biology and response to therapy. One of the main transcription factors activated by hypoxia is hypoxia-inducible factor (HIF), which regulates the expression of genes involved in various aspects of tumourigenesis including proliferative capacity, angiogenesis, immune evasion, metabolic reprogramming, extracellular matrix (ECM) remodelling, and cell migration. This can negatively impact patient outcomes by inducing therapeutic resistance. The importance of hypoxia is clearly demonstrated by continued research into finding clinically relevant hypoxia biomarkers, and hypoxia-targeting therapies. One of the problems is the lack of clinically applicable methods of hypoxia detection, and lack of standardisation. Additionally, a lot of the methods of detecting hypoxia do not take into consideration the complexity of the hypoxic tumour microenvironment (TME). Therefore, this needs further elucidation as approximately 50% of solid tumours are hypoxic. The ECM is important component of the hypoxic TME, and is developed by both cancer associated fibroblasts (CAFs) and tumour cells. However, it is important to distinguish the different roles to develop both biomarkers and novel compounds. Fibronectin (FN), collagen (COL) and hyaluronic acid (HA) are important components of the ECM that create ECM fibres. These fibres are crosslinked by specific enzymes including lysyl oxidase (LOX) which regulates the stiffness of tumours and induces fibrosis. This is partially regulated by HIFs. The review highlights the importance of understanding the role of matrix stiffness in different solid tumours as current data shows contradictory results on the impact on therapeutic resistance. The review also indicates that further research is needed into identifying different CAF subtypes and their exact roles; with some showing pro-tumorigenic capacity and others having anti-tumorigenic roles. This has made it difficult to fully elucidate the role of CAFs within the TME. However, it is clear that this is an important area of research that requires unravelling as current strategies to target CAFs have resulted in worsened prognosis. The role of immune cells within the tumour microenvironment is also discussed as hypoxia has been associated with modulating immune cells to create an anti-tumorigenic environment. Which has led to the development of immunotherapies including PD-L1. These hypoxia-induced changes can confer resistance to conventional therapies, such as chemotherapy, radiotherapy, and immunotherapy. This review summarizes the current knowledge on the impact of hypoxia on the TME and its implications for therapy resistance. It also discusses the potential of hypoxia biomarkers as prognostic and predictive indictors of treatment response, as well as the challenges and opportunities of targeting hypoxia in clinical trials.

Migrasomal autophagosomes relieve endoplasmic reticulum stress in glioblastoma cells

BACKGROUND

Glioblastoma (GBM) is more difficult to treat than other intractable adult tumors. The main reason that GBM is so difficult to treat is that it is highly infiltrative. Migrasomes are newly discovered membrane structures observed in migrating cells. Thus, they can be generated from GBM cells that have the ability to migrate along the brain parenchyma. However, the function of migrasomes has not yet been elucidated in GBM cells.

RESULTS

Here, we describe the composition and function of migrasomes generated along with GBM cell migration. Proteomic analysis revealed that LC3B-positive autophagosomes were abundant in the migrasomes of GBM cells. An increased number of migrasomes was observed following treatment with chloroquine (CQ) or inhibition of the expression of STX17 and SNAP29, which are involved in autophagosome/lysosome fusion. Furthermore, depletion of ITGA5 or TSPAN4 did not relieve endoplasmic reticulum (ER) stress in cells, resulting in cell death.

CONCLUSIONS

Taken together, our study suggests that increasing the number of autophagosomes, through inhibition of autophagosome/lysosome fusion, generates migrasomes that have the capacity to alleviate cellular stress.

Microfluidics enabled multi-omics triple-shot mass spectrometry for cell-based therapies

In recent years, cell-based therapies have transformed medical treatment. These therapies present a multitude of challenges associated with identifying the mechanism of action, developing accurate safety and potency assays, and achieving low-cost product manufacturing at scale. The complexity of the problem can be attributed to the intricate composition of the therapeutic products: living cells with complex biochemical compositions. Identifying and measuring critical quality attributes (CQAs) that impact therapy success is crucial for both the therapy development and its manufacturing. Unfortunately, current analytical methods and tools for identifying and measuring CQAs are limited in both scope and speed. This Perspective explores the potential for microfluidic-enabled mass spectrometry (MS) systems to comprehensively characterize CQAs for cell-based therapies, focusing on secretome, intracellular metabolome, and surfaceome biomarkers. Powerful microfluidic sampling and processing platforms have been recently presented for the secretome and intracellular metabolome, which could be implemented with MS for fast, locally sampled screening of the cell culture. However, surfaceome analysis remains limited by the lack of rapid isolation and enrichment methods. Developing innovative microfluidic approaches for surface marker analysis and integrating them with secretome and metabolome measurements using a common analytical platform hold the promise of enhancing our understanding of CQAs across all "omes," potentially revolutionizing cell-based therapy development and manufacturing for improved efficacy and patient accessibility.

Inhibition of ERO1a and IDO1 improves dendritic cell infiltration into pancreatic ductal adenocarcinoma

Introduction

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal and treatment resistant cancers. Due to its desmoplastic and hypoxic nature along with an abundance of myeloid cell infiltration and scarce T cell infiltration, PDAC is considered a cold tumor.

Methods

Here we sought to investigate myeloid cell infiltration and composition in PDAC spheroids by targeting the hypoxia-associated pathways endoplasmic reticulum oxidoreductase 1 alpha (ERO1a) and indoleamine 2,3-dioxygenase 1 (IDO1). Using MiaPaCa2 spheroids with hypoxic core, we assessed the roles of ERO1a and IDO1 inhibition in modulating monocyte infiltration and differentiation, followed by characterizing immunomodulatory factors secreted using LC-MS/MS.

Results

Inhibition of ERO1a and IDO1 significantly improved monocyte infiltration and differentiation into dendritic cells. LC-MS/MS analysis of the PDAC spheroid secretome identified downregulation of hypoxia and PDAC pathways, and upregulation of antigen presentation pathways upon inhibition of ERO1a and IDO1. Furthermore, immunomodulatory factors involved in immune infiltration and migration including interleukin-8, lymphocyte cytosolic protein 1, and transgelin-2, were upregulated upon inhibition of ERO1a and IDO1.

Discussion

Collectively, our results show that inhibition of ERO1a and IDO1 modulates the tumor microenvironment associated with improved monocyte infiltration and differentiation into dendritic cells to potentially influence therapeutic responses in patients with PDAC.

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.

Single-cell sequencing highlights heterogeneity and malignant progression in actinic keratosis and cutaneous squamous cell carcinoma

Cutaneous squamous cell carcinoma (cSCC) is the second most frequent of the keratinocyte-derived malignancies with actinic keratosis (AK) as a precancerous lesion. To comprehensively delineate the underlying mechanisms for the whole progression from normal skin to AK to invasive cSCC, we performed single-cell RNA sequencing (scRNA-seq) to acquire the transcriptomes of 138,982 cells from 13 samples of six patients including AK, squamous cell carcinoma in situ (SCCIS), cSCC, and their matched normal tissues, covering comprehensive clinical courses of cSCC. We identified diverse cell types, including important subtypes with different gene expression profiles and functions in major keratinocytes. In SCCIS, we discovered the malignant subtypes of basal cells with differential proliferative and migration potential. Differentially expressed genes (DEGs) analysis screened out multiple key driver genes including transcription factors along AK to cSCC progression. Immunohistochemistry (IHC)/immunofluorescence (IF) experiments and single-cell ATAC sequencing (scATAC-seq) data verified the expression changes of these genes. The functional experiments confirmed the important roles of these genes in regulating cell proliferation, apoptosis, migration, and invasion in cSCC tumor. Furthermore, we comprehensively described the tumor microenvironment (TME) landscape and potential keratinocyte-TME crosstalk in cSCC providing theoretical basis for immunotherapy. Together, our findings provide a valuable resource for deciphering the progression from AK to cSCC and identifying potential targets for anticancer treatment of cSCC.

Mesenchymal Stem Cells: Their Role in the Tumor Microenvironment

Mesenchymal stem cells (MSCs) have been seen for years as great candidates for treating different diseases and an alternative to embryonic stem cells due to their differentiation capacity in vitro. More recent research has focused on their ability to modulate the immune response and regeneration at sites associated with inflammation, activities attributable to the release of trophic factors into the extracellular medium, a set of components known as the secretome. It has been possible to demonstrate the presence of these cells within the tumor microenvironment, which is associated with their tropism for sites of inflammation; however, their role here needs to be clarified. In different investigations, the feasibility of using MSCs or their secretome to treat cancer has been sought, with these results being ambiguous. It has been described that MSCs can be activated and present various phenotypes, which could explain the divergence in their action; however, these activation mechanisms and the different phenotypes still need to be well known. This review explores MSCs and their use in regenerative medicine with a targeted approach to cancer. Impact Statement This text addresses the diverging findings on the role of mesenchymal stem cells in the tumor microenvironment and discrepancies on the use of these cells as cancer treatment, separating the direct use of the cells from the use of the secretome. Multiple authors refer equally to the cells and their secretome to conclude on the positive or negative outcome, without taking into consideration how the cells are affected by their surroundings.

Synergistic inhibition of NUDT21 by secretory S100A11 and exosomal miR-487a-5p promotes melanoma oligo- to poly-metastatic progression

Although early diagnosis and therapeutic advances have transformed the living quality and outcome of cancer patients, the poor prognosis for metastatic patients has not been significantly improved. Mechanisms underlying the complexity of metastasis cannot be simply determined by the straightforward 'cause-and-effect relationships'. We have developed a 'dry-lab-driven knowledge discovery and wet-lab validation' approach to embrace the complexity of cancer and metastasis. We have revealed for the first time that polymetastatic (POL) melanoma cells can utilize both the secretory protein pathway (S100A11-Sec23a) and the exosomal crosstalk (miR-487a-5p) to transfer their 'polymetastatic competency' to the oligometastatic (OL) melanoma cells, via synergistic co-targeting of the tumor-suppressor Nudt21. The downstream deregulated glycolysis was verified to regulate metastatic colonization efficiency. Further, two gene sets conferring independent prognosis in melanoma were identified, which have the potential for clinical translation and merit future clinical validation.

A Subset of Colon Cancer Cell Lines Displays a Cytokine Profile Linked to Angiogenesis, EMT and Invasion Which Is Modulated by the Culture Conditions In Vitro

Colorectal cancer (CRC) is one of the deadliest cancers worldwide. The dysregulation of secretory pathways is a crucial driver of CRC progression, since it modulates cell proliferation, angiogenesis and survival. This study explores the changes in the CRC cytokine profile depending on the culture conditions and the presence of fibroblasts and macrophages as cellular components of the tumor microenvironment in 2D and in 3D formed spheroids. Upon analysis of 45 different cytokines, chemokines and growth factors, 20 CRC cell lines were categorized into high and low secretors. In the high secretor group cytokines related to angiogenesis, EMT and invasion were significantly upregulated. LIF and HFG were identified as the best discriminator between both groups. Independent of this grouping, the addition of normal as well as cancer-associated fibroblasts had a similar impact on the cytokine profile by increasing the total amount of secreted cytokines in most of the investigated cell lines. In contrast, the differentiation and polarization of macrophages was modulated differently by normal vs. cancer-associated fibroblasts. In summary, we identified two groups of CRC cell lines that differ in their cytokine profile. The dependance of this profile was analyzed in detail-not only from the tumor cell line but as well from the culture condition in vitro. Key cytokines that discriminate the two groups were identified and their importance as promising biomarker candidates for CRC discussed.

The Inhibition of the FGFR/PI3K/Akt Axis by AZD4547 Disrupts the Proangiogenic Microenvironment and Vasculogenic Mimicry Arising from the Interplay between Endothelial and Triple-Negative Breast Cancer Cells

Vasculogenic mimicry (VM), a process in which aggressive cancer cells form tube-like structures, plays a crucial role in providing nutrients and escape routes. Highly plastic tumor cells, such as those with the triple-negative breast cancer (TNBC) phenotype, can develop VM. However, little is known about the interplay between the cellular components of the tumor microenvironment and TNBC cells' VM capacity. In this study, we analyzed the ability of endothelial and stromal cells to induce VM when interacting with TNBC cells and analyzed the involvement of the FGFR/PI3K/Akt pathway in this process. VM was corroborated using fluorescently labeled TNBC cells. Only endothelial cells triggered VM formation, suggesting a predominant role of paracrine/juxtacrine factors from an endothelial origin in VM development. Via immunocytochemistry, qPCR, and secretome analyses, we determined an increased expression of proangiogenic factors as well as stemness markers in VM-forming cancer cells. Similarly, endothelial cells primed by TNBC cells showed an upregulation of proangiogenic molecules, including FGF, VEGFA, and several inflammatory cytokines. Endothelium-dependent TNBC-VM formation was prevented by AZD4547 or LY294002, strongly suggesting the involvement of the FGFR/PI3K/Akt axis in this process. Given that VM is associated with poor clinical prognosis, targeting FGFR/PI3K/Akt pharmacologically may hold promise for treating and preventing VM in TNBC tumors.

Modulation of cellular transcriptome and proteome composition by azidohomoalanine-implications on click chemistry-based secretome analysis

The analysis of the secretome provides important information on proteins defining intercellular communication and the recruitment and behavior of cells in specific tissues. Especially in the context of tumors, secretome data can support decisions for diagnosis and therapy. The mass spectrometry-based analysis of cell-conditioned media is widely used for the unbiased characterization of cancer secretomes in vitro. Metabolic labeling using azide-containing amino acid analogs in combination with click chemistry facilitates this type of analysis in the presence of serum, preventing serum starvation-induced effects. The modified amino acid analogs, however, are less efficiently incorporated into newly synthesized proteins and may perturb protein folding. Combining transcriptome and proteome analysis, we elucidate in detail the effects of metabolic labeling with the methionine analog azidohomoalanine (AHA) on gene and protein expression. Our data reveal that 15-39% of the proteins detected in the secretome displayed changes in transcript and protein expression induced by AHA labeling. Gene Ontology (GO) analyses indicate that metabolic labeling using AHA leads to induction of cellular stress and apoptosis-related pathways and provide first insights on how this affects the composition of the secretome on a global scale. KEY MESSAGES: Azide-containing amino acid analogs affect gene expression profiles. Azide-containing amino acid analogs influence cellular proteome. Azidohomoalanine labeling induces cellular stress and apoptotic pathways. Secretome consists of proteins with dysregulated expression profiles.

Emerging organoid-immune co-culture models for cancer research: from oncoimmunology to personalized immunotherapies

In the past decade, treatments targeting the immune system have revolutionized the cancer treatment field. Therapies such as immune checkpoint inhibitors have been approved as first-line treatment in a variety of solid tumors such as melanoma and non-small cell lung cancer while other therapies, for instance, chimeric antigen receptor (CAR) lymphocyte transfer therapies, are still in development. Although promising results are obtained in a small subset of patients, overall clinical efficacy of most immunotherapeutics is limited due to intertumoral heterogeneity and therapy resistance. Therefore, prediction of patient-specific responses would be of great value for efficient use of costly immunotherapeutic drugs as well as better outcomes. Because many immunotherapeutics operate by enhancing the interaction and/or recognition of malignant target cells by T cells, in vitro cultures using the combination of these cells derived from the same patient hold great promise to predict drug efficacy in a personalized fashion. The use of two-dimensional cancer cell lines for such cultures is unreliable due to altered phenotypical behavior of cells when compared with the in vivo situation. Three-dimensional tumor-derived organoids, better mimic in vivo tissue and are deemed a more realistic approach to study the complex tumor-immune interactions. In this review, we present an overview of the development of patient-specific tumor organoid-immune co-culture models to study the tumor-specific immune interactions and their possible therapeutic infringement. We also discuss applications of these models which advance personalized therapy efficacy and understanding the tumor microenvironment such as: (1) Screening for efficacy of immune checkpoint inhibition and CAR therapy screening in a personalized manner. (2) Generation of tumor reactive lymphocytes for adoptive cell transfer therapies. (3) Studying tumor-immune interactions to detect cell-specific roles in tumor progression and remission. Overall, these onco-immune co-cultures might hold a promising future toward developing patient-specific therapeutic approaches as well as increase our understanding of tumor-immune interactions.

Genomic Interplay between Neoneurogenesis and Neoangiogenesis in Carcinogenesis: Therapeutic Interventions

Angiogenesis, the generation of new blood vessels, is one of the hallmarks of cancer. The growing tumor requires nutrients and oxygen. Recent evidence has shown that tumors release signals to attract new nerve fibers and stimulate the growth of new nerve fibers. Neurogenesis, neural extension, and axonogenesis assist in the migration of cancer cells. Cancer cells can use both blood vessels and nerve fibers as routes for cells to move along. In this way, neurogenesis and angiogenesis both contribute to cancer metastasis. As a result, tumor-induced neurogenesis joins angiogenesis and immunosuppression as aberrant processes that are exacerbated within the tumor microenvironment. The relationship between these processes contributes to cancer development and progression. The interplay between these systems is brought about by cytokines, neurotransmitters, and neuromodulators, which activate signaling pathways that are common to angiogenesis and the nervous tissue. These include the AKT signaling pathways, the MAPK pathway, and the Ras signaling pathway. These processes also both require the remodeling of tissues. The interplay of these processes in cancer provides the opportunity to develop novel therapies that can be used to target these processes.

Integrated technologies for continuous monitoring of organs-on-chips: Current challenges and potential solutions

Organs-on-chips (OoCs) are biomimetic in vitro systems based on microfluidic cell cultures that recapitulate the in vivo physicochemical microenvironments and the physiologies and key functional units of specific human organs. These systems are versatile and can be customized to investigate organ-specific physiology, pathology, or pharmacology. They are more physiologically relevant than traditional two-dimensional cultures, can potentially replace the animal models or reduce the use of these models, and represent a unique opportunity for the development of personalized medicine when combined with human induced pluripotent stem cells. Continuous monitoring of important quality parameters of OoCs via a label-free, non-destructive, reliable, high-throughput, and multiplex method is critical for assessing the conditions of these systems and generating relevant analytical data; moreover, elaboration of quality predictive models is required for clinical trials of OoCs. Presently, these analytical data are obtained by manual or automatic sampling and analyzed using single-point, off-chip traditional methods. In this review, we describe recent efforts to integrate biosensing technologies into OoCs for monitoring the physiologies, functions, and physicochemical microenvironments of OoCs. Furthermore, we present potential alternative solutions to current challenges and future directions for the application of artificial intelligence in the development of OoCs and cyber-physical systems. These "smart" OoCs can learn and make autonomous decisions for process optimization, self-regulation, and data analysis.

Exploring the macromolecules for secretory pathway in cancer disease

Secretory proteins play an important role in the tumor microenvironment and are widely distributed throughout tumor tissues. Tumor cells secrete a protein that mediates communication between tumor cells and stromal cells, thereby controlling tumor growth and affecting the success of cancer treatments in the clinic. The cancer secretome is produced by various secretory pathways and has a wide range of applications in oncoproteomics. Secretory proteins are involved in cancer development and tumor cell migration, and thus serve as biomarkers or effective therapeutic targets for a variety of cancers. Several proteomic strategies have recently been used for the analysis of cancer secretomes in order to gain a better understanding and elaborate interpretation. For instance, the development of exosome proteomics, degradomics, and tumor-host cell interaction provide clear information regarding the mechanism of cancer pathobiology. In this chapter, we emphasize the recent advances in secretory protein and the challenges in the field of secretome analysis and their clinical applications.

Cancer secretome: finding out hidden messages in extracellular secretions

Secretome analysis has gained popularity recently as a very well-designed proteomic approach that is being used to study various interactions and their effects on cellular activity. This analysis is especially helpful while studying the effects of the cells on their microenvironment, paracrine and autocrine processes, their therapeutic purposes, and as a new diagnostic perspective. Cancer is a condition rather than a specific type of disease and is still yet to be fully understood. Cancer secretome is a fairly new concept that is being implemented to examine the interactions taking place in the tumor microenvironment and can help to understand the phenomena like induction of tumorigenesis, stimulation of immune cells, etc. The secretome analysis helps to gain a different perspective on the existing knowledge on cancer and its effects. The recent advances in secretome studies are directed toward secreted components as drug targets, biomarkers, and companion tools for diagnostic and prognostic purposes in cancer. This review aims to find the interactors in different types of cancer and understand the existing unstructured secretome data and its application in prognosis, diagnosis, and in biomarker study.

Reprogramming of cancer-associated fibroblasts by apoptotic cancer cells inhibits lung metastasis via Notch1-WISP-1 signaling

The interplay between apoptotic cancer cells and the tumor microenvironment modulates cancer progression and metastasis. Cancer-associated fibroblasts (CAFs) play a crucial role in promoting these events through paracrine communication. Here, we demonstrate that conditioned medium (CM) from lung CAFs exposed to apoptotic cancer cells suppresses TGF-β1-induced migration and invasion of cancer cells and CAFs. Direct exposure of CAFs to apoptotic 344SQ cells (ApoSQ) inhibited CAF migration and invasion and the expression of CAF activation markers. Enhanced secretion of Wnt-induced signaling protein 1 (WISP-1) by CAFs exposed to ApoSQ was required for these antimigratory and anti-invasive effects. Pharmacological inhibition of Notch1 activation or siRNA-mediated Notch1 silencing prevented WISP-1 production by CAFs and reversed the antimigratory and anti-invasive effects. Enhanced expression of the Notch ligand delta-like protein 1 on the surface of ultraviolet-irradiated apoptotic lung cancer cells triggered Notch1-WISP-1 signaling. Phosphatidylserine receptor brain-specific angiogenesis inhibitor 1 (BAI1)-Rac1 signaling, which facilitated efferocytosis by CAFs, participated in crosstalk with Notch1 signaling for optimal production of WISP-1. In addition, a single injection of ApoSQ enhanced WISP-1 production, suppressed the expression of CAF activation markers in isolated Thy1⁺ CAFs, and inhibited lung metastasis in syngeneic immunocompetent mice via Notch1 signaling. Treatment with CM from CAFs exposed to ApoSQ suppressed tumor growth and lung metastasis, whereas treatment with WISP-1-immunodepleted CM from CAFs exposed to ApoSQ reversed the antitumorigenic and antimetastatic effects. Therefore, treatment with CM from CAFs exposed to apoptotic lung cancer cells could be therapeutically applied to suppress CAF activation, thereby preventing cancer progression and metastasis.

Research progress on anti-ovarian cancer mechanism of miRNA regulating tumor microenvironment

Ovarian cancer is the most deadly malignancy among women, but its complex pathogenesis is unknown. Most patients with ovarian cancer have a poor prognosis due to high recurrence rates and chemotherapy resistance as well as the lack of effective early diagnostic methods. The tumor microenvironment mainly includes extracellular matrix, CAFs, tumor angiogenesis and immune-associated cells. The interaction between tumor cells and TME plays a key role in tumorigenesis, progression, metastasis and treatment, affecting tumor progression. Therefore, it is significant to find new tumor biomarkers and therapeutic targets. MicroRNAs are non-coding RNAs that post-transcriptionally regulate the expression of target genes and affect a variety of biological processes. Studies have shown that miRNAs regulate tumor development by affecting TME. In this review, we summarize the mechanisms by which miRNAs affect ovarian cancer by regulating TME and highlight the key role of miRNAs in TME, which provides new targets and theoretical basis for ovarian cancer treatment.

Enhanced Diabetic Wound Healing Using Electrospun Biocompatible PLGA-Based Saxagliptin Fibrous Membranes

Delayed diabetic wound healing is an adverse event that frequently leads to limb disability or loss. A novel and promising vehicle for the treatment of diabetic wounds is required for clinical purposes. The biocompatible and resorbable poly (lactic-co-glycolic acid) (PLGA)-based fibrous membranes prepared by electrospinning that provide a sustained discharge of saxagliptin for diabetic wound healing were fabricated. The concentration of released saxagliptin in Dulbecco’s phosphate-buffered saline was analyzed for 30 days using high-performance liquid chromatography. The effectiveness of the eluted saxagliptin was identified using an endothelial progenitor cell migration assay in vitro and a diabetic wound healing in vivo. Greater hydrophilicity and water storage were shown in the saxagliptin-incorporated PLGA membranes than in the pristine PLGA membranes (both p < 0.001). For diabetic wound healing, the saxagliptin membranes accelerated the wound closure rate, the dermal thickness, and the heme oxygenase-1 level over the follicle areas compared to those in the pristine PLGA group at two weeks post-treatment. The saxagliptin group also had remarkably higher expressions of insulin-like growth factor I expression and transforming growth factor-β1 than the control group (p = 0.009 and p < 0.001, respectively) in diabetic wounds after treatment. The electrospun PLGA-based saxagliptin membranes exhibited excellent biomechanical and biological features that enhanced diabetic wound closure and increased the antioxidant activity, cellular granulation, and functionality.

Cancer-associated inflammation: pathophysiology and clinical significance

Purpose

Cancer cells, despite stemming from the own cells of their host, usually elicit an immune response. This response usually enables elimination of cancer at its earliest stages. However, some tumors develop mechanisms of escaping immune destruction and even profiting from tumor-derived inflammation.

Methods

We summarized the roles of different immune cell populations in various processes associated with cancer progression and possible methods of reshaping tumor-associated inflammation to increase the efficacy of cancer therapy.

Results

Changes in various signaling pathways result in attraction of immunosuppressive, pro-tumorigenic cells, such as myeloid-derived suppressor cells, tumor-associated macrophages, and neutrophils, while at the same time suppressing the activity of lymphocytes, which have the potential of destroying cancer cells. These changes promote tumor progression by increasing angiogenesis and growth, accelerating metastasis, and impairing drug delivery to the tumor site.

Conclusion

Due to its multi-faceted role in cancer, tumor-associated inflammation can serve as a valuable therapy target. By increasing it, whether through decreasing overall immunosuppression with immune checkpoint inhibitor therapy or through more specific methods, such as cancer vaccines, oncolytic viruses, or chimeric antigen receptor T cells, cancer-derived immunosuppression can be overcome, resulting in immune system destroying cancer cells. Even changes occurring in the microbiota can influence the shape of antitumor response, which could provide new attractive diagnostic or therapeutic methods. Interestingly, also decreasing the distorted tumor-associated inflammation with non-steroidal anti-inflammatory drugs can lead to positive outcomes.

Antibody-mediated blockade for galectin-3 binding protein in tumor secretome abrogates PDAC metastasis

The major challenges in pancreatic ductal adenocarcinoma (PDAC) management are local or distant metastasis and limited targeted therapeutics to prevent it. To identify a druggable target in tumor secretome and to explore its therapeutic intervention, we performed a liquid chromatography-tandem mass spectrometry (LC-MS/MS)-based proteomic analysis of tumors obtained from a patient-derived xenograft model of PDAC. Galectin-3 binding protein (Gal-3BP) is identified as a highly secreted protein, and its overexpression is further validated in multiple PDAC tumors and primary cells. Knockdown and exogenous treatment of Gal-3BP showed that it is required for PDAC cell proliferation, migration, and invasion. Mechanistically, we revealed that Gal-3BP enhances galectin-3-mediated epidermal growth factor receptor signaling, leading to increased cMyc and epithelial-mesenchymal transition. To explore the clinical impact of these findings, two antibody clones were developed, and they profoundly abrogated the metastasis of PDAC cells in vivo. Altogether, our data demonstrate that Gal-3BP is an important therapeutic target in PDAC, and we propose its blockade by antibody as a therapeutic option for suppressing PDAC metastasis.

Interplay Between Immune and Cancer-Associated Fibroblasts: A Path to Target Metalloproteinases in Penile Cancer

Extracellular matrix (ECM) remodeling and inflammation have been reported in penile carcinomas (PeCa). However, the cell types and cellular crosstalk involved in PeCa are unexplored. We aimed to characterize the complexity of cells and pathways involved in the tumor microenvironment (TME) in PeCa and propose target molecules associated with the TME. We first investigated the prognostic impact of cell types with a secretory profile to identify drug targets that modulate TME-enriched cells. The secretome analysis using the PeCa transcriptome revealed the enrichment of inflammation and extracellular matrix pathways. Twenty-three secreted factors were upregulated, mainly collagens and matrix metalloproteinases (MMPs). The deregulation of collagens and MMPs was confirmed by Quantitative reverse transcription - polymerase chain reaction (RT-qPCR). Further, the deconvolution method (digital cytometry) of the bulk samples revealed a high proportion of macrophages and dendritic cells (DCs) and B cells. Increased DCs and B cells were associated with better survival. A high proportion of cancer-associated fibroblasts (CAFs) was observed in low-survival patients. Patients with increased CAFs had decreased immune cell proportions. The treatment with the MMP inhibitor GM6001 in CAF cells derived from PeCa resulted in altered cell viability. We reported a crosstalk between immune cells and CAFs, and the proportion of these cell populations was associated with prognosis. We demonstrate that a drug targeting MMPs modulates CAFs, expanding the therapeutic options of PeCa.

Extracellular Hsp90α Supports the ePKM2-GRP78-AKT Axis to Promote Tumor Metastasis

Tumor-secreted proteins can provide numerous molecular targets for cancer diagnosis and treatment. Of note, pyruvate kinase M2 (PKM2) is secreted by tumor cells to promote malignant progression, while its regulatory mechanism or the interacting network remains uncovered. In the present study, we identified extracellular heat shock protein 90 alpha (eHsp90α) as one potential interacting protein of ePKM2 by mass spectrometry (MS), which was further verified by pull-down and co-immunoprecipitation analysis. Later, we found that eHsp90α enhanced the effect of ePKM2 on migration and invasion of lung cancer cells. Blocking of Hsp90α activity, on the other hand, attenuated tumor migration or invasion induced by ePKM2. Eventually, the in vivo role of Hsp90α in regulating ePKM2 activity was validated by the mouse xenograft tumor model. Mechanistically, we found that eHsp90α binds to and stabilizes ePKM2 to protect it from degradation in the extracellular environment. Besides, eHsp90α promoted the interaction of ePKM2 with cell surface receptor GRP78, which leads to the activation of the ePKM2/GRP78/AKT axis. Collectively, we unraveled the novel molecular mechanism of eHsp90α in regulating ePKM2 activity during tumor progression, which is beneficial for the development of new treatments against lung cancer.

M-CSF as a therapeutic target in BRAFV600E melanoma resistant to BRAF inhibitors

BACKGROUND

Disseminated BRAF^V600E melanoma responds to BRAF inhibitors (BRAFi) but easily develops resistance with poor prognosis. Secretome plays a pivotal role during tumour progression causing profound effects on therapeutic efficacy. Secreted M-CSF is involved in both cytotoxicity suppression and tumour progression in melanoma. We aimed to analyse the M-CSF contribution in resistant metastatic melanoma to BRAF-targeted therapies.

METHODS

Conditioned media from melanoma cells were analysed by citoarray. Viability and migration/invasion assays were performed with paired melanoma cells and tumour growth in xenografted SCID mice. We evaluated the impact of M-CSF plasma levels with clinical prognosis from 35 metastatic BRAF^V600E-mutant melanoma patients.

RESULTS

BRAFi-resistant melanoma cells secretome is rich in pro-tumour cytokines. M-CSF secretion is essential to induce a Vemurafenib-resistant phenotype in melanoma cells. Further, we demonstrated that M-CSF mAb in combination with Vemurafenib and autophagy blockers synergistically induce apoptosis, impair migration and reduce tumour growth in BRAFi-resistant melanoma cells. Interestingly, lower M-CSF plasma levels are associated with better prognosis in metastatic melanoma patients.

CONCLUSIONS

Secreted M-CSF induces a BRAFi-resistant phenotype and means worse prognosis in BRAF^V600E metastatic melanoma patients. These results identify secreted M-CSF as a promising therapeutic target toward BRAFi-resistant melanomas.

Comparing the Secretomes of Chemorefractory and Chemoresistant Ovarian Cancer Cell Populations

High-grade serous ovarian cancer (HGSOC) constitutes the majority of all ovarian cancer cases and has staggering rates of both refractory and recurrent disease. While most patients respond to the initial treatment with paclitaxel and platinum-based drugs, up to 25% do not, and of the remaining that do, 75% experience disease recurrence within the subsequent two years. Intrinsic resistance in refractory cases is driven by environmental stressors like tumor hypoxia which alter the tumor microenvironment to promote cancer progression and resistance to anticancer drugs. Recurrent disease describes the acquisition of chemoresistance whereby cancer cells survive the initial exposure to chemotherapy and develop adaptations to enhance their chances of surviving subsequent treatments. Of the environmental stressors cancer cells endure, exposure to hypoxia has been identified as a potent trigger and priming agent for the development of chemoresistance. Both in the presence of the stress of hypoxia or the therapeutic stress of chemotherapy, cancer cells manage to cope and develop adaptations which prime populations to survive in future stress. One adaptation is the modification in the secretome. Chemoresistance is associated with translational reprogramming for increased protein synthesis, ribosome biogenesis, and vesicle trafficking. This leads to increased production of soluble proteins and extracellular vesicles (EVs) involved in autocrine and paracrine signaling processes. Numerous studies have demonstrated that these factors are largely altered between the secretomes of chemosensitive and chemoresistant patients. Such factors include cytokines, growth factors, EVs, and EV-encapsulated microRNAs (miRNAs), which serve to induce invasive molecular, biophysical, and chemoresistant phenotypes in neighboring normal and cancer cells. This review examines the modifications in the secretome of distinct chemoresistant ovarian cancer cell populations and specific secreted factors, which may serve as candidate biomarkers for aggressive and chemoresistant cancers.

Cytokine and Chemokine Receptor Patterns of Human Malignant Melanoma Cell Lines

Cytokine and chemokine receptors can promote tumor progression, invasion, and metastasis development by inducing different intracellular signaling pathways. The aim of this study was to determine the cytokine and chemokine receptor gene expression patterns in human melanoma cell lines. We found a large set of cytokine and chemokine receptor genes that were significantly differentially expressed between melanoma cell lines that originated from different subtypes of primary melanomas as well as cell lines that originated from melanoma metastases. The relative expressions of two receptor genes (CCR2 and TNFRSF11B) were positively correlated with the invasive potential of the cell lines, whereas a negative correlation was observed for the TNFRSF14 gene expression. We also found a small set of receptor genes that exhibited a significantly decreased expression in association with a BRAFV600E mutation. Based on our results, we assume that the analyzed cytokine and chemokine receptor collection may provide potential to distinguish the different subtypes of melanomas, helping us to understand the biological behavior of BRAFV600E-mutated melanoma cells.

Cancer-Associated Fibroblasts: Mechanisms of Tumor Progression and Novel Therapeutic Targets

Simple Summary

The tumor microenvironment plays an important role in determining the biological behavior of several of the more aggressive malignancies. Among the various cell types evident in the tumor “field”, cancer-associated fibroblasts (CAFs) are a heterogenous collection of activated fibroblasts secreting a wide repertoire of factors that regulate tumor development and progression, inflammation, drug resistance, metastasis and recurrence. Insensitivity to chemotherapeutics and metastatic spread are the major contributors to cancer patient mortality. This review discusses the complex interactions between CAFs and the various populations of normal and neoplastic cells that interact within the dynamic confines of the tumor microenvironment with a focus on the involved pathways and genes.

Abstract

Cancer-associated fibroblasts (CAFs) are a heterogenous population of stromal cells found in solid malignancies that coexist with the growing tumor mass and other immune/nonimmune cellular elements. In certain neoplasms (e.g., desmoplastic tumors), CAFs are the prominent mesenchymal cell type in the tumor microenvironment, where their presence and abundance signal a poor prognosis in multiple cancers. CAFs play a major role in the progression of various malignancies by remodeling the supporting stromal matrix into a dense, fibrotic structure while secreting factors that lead to the acquisition of cancer stem-like characteristics and promoting tumor cell survival, reduced sensitivity to chemotherapeutics, aggressive growth and metastasis. Tumors with high stromal fibrotic signatures are more likely to be associated with drug resistance and eventual relapse. Clarifying the molecular basis for such multidirectional crosstalk among the various normal and neoplastic cell types present in the tumor microenvironment may yield novel targets and new opportunities for therapeutic intervention. This review highlights the most recent concepts regarding the complexity of CAF biology including CAF heterogeneity, functionality in drug resistance, contribution to a progressively fibrotic tumor stroma, the involved signaling pathways and the participating genes.

The acidic tumour microenvironment: Manipulating the immune response to elicit escape

The success of cancer treatment relies on the composition of the tumour microenvironment which is comprised of tumour cells, blood vessels, stromal cells, immune cells, and extracellular matrix components. Barriers to effective cancer treatment need to be overcome, and the acidic microenvironment of the tumour provides a key target for treatment. This review intends to provide an overview of the effects that low extracellular pH has on components of the tumour microenvironment and how they contribute to immune escape. Further, potential therapeutic targets will be discussed.

Secreted protein markers in oral squamous cell carcinoma (OSCC)

Background

Oral squamous cell carcinoma (OSCC) is a main cause of oral cancer mortality and morbidity in central south Asia. To improve the clinical outcome of OSCC patients, detection markers are needed, which are preferably non-invasive and thus independent of a tissue biopsy.

Methods

In the present study, we aimed to identify robust candidate protein biomarkers for non-invasive OSCC diagnosis. To this end, we measured the global protein profiles of OSCC tissue lysates to matched normal adjacent mucosa samples (n = 14) and the secretomes of nine HNSCC cell lines using LC–MS/MS-based proteomics.

Results

A total of 5123 tissue proteins were identified, of which 205 were robustly up- regulated (p-value < 0.01, fold change > + 2) in OSCC-tissues compared to normal adjacent tissues. The biological process “Secretion” was highly enriched in this set of proteins. Other upregulated biological pathways included “Unfolded Protein Response”, “Spliceosomal complex assembly”, “Protein localization to endosome” and “Interferon Gamma Response”. Transcription factor analysis implicated Creb3L1, ESRRA, YY, ELF2, STAT1 and XBP as potential regulators. Of the 205 upregulated tissue proteins, 132 were identified in the cancer cell line secretomes, underscoring their potential use as non-invasive biofluid markers. To further prioritize our candidate markers for non-invasive OSCC detection, we integrated our data with public biofluid datasets including OSCC saliva, yielding 25 candidate markers for further study.

Conclusions

We identified several key proteins and processes that are associated with OSCC tissues, underscoring the importance of altered secretion. Cancer-associated OSCC secretome proteins present in saliva have potential to be used as novel non-invasive biomarkers for the diagnosis of OSCC.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12014-022-09341-5.

Cancer exosomes and natural killer cells dysfunction: biological roles, clinical significance and implications for immunotherapy

Tumor-derived exosomes (TDEs) play pivotal roles in several aspects of cancer biology. It is now evident that TDEs also favor tumor growth by negatively affecting anti-tumor immunity. As important sentinels of immune surveillance system, natural killer (NK) cells can recognize malignant cells very early and counteract the tumor development and metastasis without a need for additional activation. Based on this rationale, adoptive transfer of ex vivo expanded NK cells/NK cell lines, such as NK-92 cells, has attracted great attention and is widely studied as a promising immunotherapy for cancer treatment. However, by exploiting various strategies, including secretion of exosomes, cancer cells are able to subvert NK cell responses. This paper reviews the roles of TDEs in cancer-induced NK cells impairments with mechanistic insights. The clinical significance and potential approaches to nullify the effects of TDEs on NK cells in cancer immunotherapy are also discussed.