Cancer-associated fibroblasts do not respond to combined irradiation and kinase inhibitor treatment

Research progress on prognostic factors of gallbladder carcinoma

BACKGROUND

Gallbladder carcinoma is the most common malignant tumor of the biliary system, and has a poor overall prognosis. Poor prognosis in patients with gallbladder carcinoma is associated with the aggressive nature of the tumor, subtle clinical symptoms, ineffective adjuvant treatment, and lack of reliable biomarkers.

PURPOSE

Therefore, evaluating the prognostic factors of patients with gallbladder carcinoma can help improve diagnostic and treatment methods, allowing for tailored therapies that could benefit patient survival.

METHODS

This article systematically reviews the factors affecting the prognosis of gallbladder carcinoma, with the aim of evaluating prognostic risk in patients.

CONCLUSION

A comprehensive and in-depth understanding of prognostic indicators affecting patient survival is helpful for assessing patient survival risk and formulating personalized treatment plans.

Ionizing radiation-induced "zombie" carcinoma-associated fibroblasts with suppressed pro-radioresistance on OSCC cells

OBJECTIVES

This study was to investigate the effect of ionizing radiation (IR) on oral carcinoma-associated fibroblasts (CAFs) and to further explore subsequent effects of IR-induced "zombie" CAFs on oral squamous cell carcinoma (OSCC) cells.

MATERIALS AND METHODS

Three primary CAFs and one primary normal-associated fibroblasts (NAFs) were separated from human OSCC and normal oral mucosa tissues, identified by immunocytochemistry. Cells were exposed to IR by X-ray irradiator under different doses. The DNA damage, proliferation, and migration of irradiated CAFs were, respectively, detected by immunofluorescence and wound healing assay, while senescence was detected by β-galactosidase staining. Finally, the effect of irradiated CAFs on biological behavior and radioresistance of Cal-27 cells were determined via assays mentioned above.

RESULTS

Oral CAFs were sensitive to IR with DNA damage increasing and proliferation decreasing. 18 Gy IR could not kill oral CAFs but induce them to "zombies," with arrested proliferation, increased senescence, and reduced migration. "Zombie" CAFs (zCAFs) could enhance proliferation, migration, and invasion of Cal-27 cells, and show suppressed pro-radioresistance by reducing DNA damage and facilitating survival.

CONCLUSIONS

IR-induced zCAFs could continuously promote radioresistance of OSCC cells though being suppressed, suggesting the potential promoting effect on tumor relapse post-radiotherapy that needed further exploring.

Cancer-Associated Fibroblast Functions as a Road-Block in Cancer Therapy

The journey of a normal resident fibroblast belonging to the tumor microenvironment (TME) from being a tumor pacifier to a tumor patron is fascinating. We introduce cancer-associated fibroblast (CAF) as a crucial component of the TME. Activated-CAF partners with tumor cells and all components of TME in an established solid tumor. We briefly overview the origin, activation, markers, and overall functions of CAF with a particular reference to how different functions of CAF in an established tumor are functionally connected to the development of resistance to cancer therapy in solid tumors. We interrogate the role of CAF in mediating resistance to different modes of therapies. Functional diversity of CAF in orchestrating treatment resistance in solid tumors portrays CAF as a common orchestrator of treatment resistance; a roadblock in cancer therapy.

Portrait of a CAF: The story of cancer-associated fibroblasts in head and neck cancer

Complex interactions take place during cancer formation and progression. In this regard, there has been increasing focus on the non-malignant cells that make up the tumour microenvironment (TME), and how they interact with malignant tumour cells. TME is highly heterogeneous and has a major influence on tumour behaviour and therapy response. Cancer-associated fibroblasts (CAFs), one of the main components of the TME, establish dangerous liaisons with cancer cells and other components of the TME to shape a tumour-supportive environment in many types of cancer. Head and neck squamous cell carcinoma (HNSCC) encompass the malignant neoplasms arising from the mucosal lining of the oral cavity, pharynx and larynx. The TME of HNSCC contributes to tumour progression and this stromal compartment may be an interesting target for treatment. There is an emerging picture of the behaviour of CAFs in HNSCC; how they affect and are affected by the TME. We aim to summarise and discuss the current understanding of CAFs in head and neck cancer, exploring CAF activation and heterogeneity, and interaction with cancer cells and other cells within the TME.

Organotypic Co-Cultures as a Novel 3D Model for Head and Neck Squamous Cell Carcinoma

Background: Head and neck squamous cell carcinomas (HNSCC) are phenotypically and molecularly heterogeneous and frequently develop therapy resistance. Reliable patient-derived 3D tumor models are urgently needed to further study the complex pathogenesis of these tumors and to overcome treatment failure. Methods: We developed a three-dimensional organotypic co-culture (3D-OTC) model for HNSCC that maintains the architecture and cell composition of the individual tumor. A dermal equivalent (DE), composed of healthy human-derived fibroblasts and viscose fibers, served as a scaffold for the patient sample. DEs were co-cultivated with 13 vital HNSCC explants (non-human papillomavirus (HPV) driven, n = 7; HPV-driven, n = 6). Fractionated irradiation was applied to 5 samples (non-HPV-driven, n = 2; HPV-driven n = 3). To evaluate expression of ki-67, cleaved caspase-3, pan-cytokeratin, p16^INK4a, CD45, ∝smooth muscle actin and vimentin over time, immunohistochemistry and immunofluorescence staining were performed Patient checkup data were collected for up to 32 months after first diagnosis. Results: All non-HPV-driven 3D-OTCs encompassed proliferative cancer cells during cultivation for up to 21 days. Proliferation indices of primaries and 3D-OTCs were comparable and consistent over time. Overall, tumor explants displayed heterogeneous growth patterns (i.e., invasive, expansive, silent). Cancer-associated fibroblasts and leukocytes could be detected for up to 21 days. HPV DNA was detectable in both primary and 3D-OTCs (day 14) of HPV-driven tumors. However, p16^INK4a expression levels were varying. Morphological alterations and radioresistant tumor cells were detected in 3D-OTC after fractionated irradiation in HPV-driven and non-driven samples. Conclusions: Our 3D-OTC model for HNSCC supports cancer cell survival and proliferation in their original microenvironment. The model enables investigation of invasive cancer growth and might, in the future, serve as a platform to perform sensitivity testing upon treatment to predict therapy response.

Cancer-associated fibroblast regulation of tumor neo-angiogenesis as a therapeutic target in cancer

Adequate blood supply is essential for tumor survival, growth and metastasis. The tumor microenvironment (TME) is dynamic and complex, comprising cancer cells, cancer-associated stromal cells and their extracellular products. The TME serves an important role in tumor progression. Cancer-associated fibroblasts (CAFs) are the principal component of stromal cells within the TME, and contribute to tumor neo-angiogenesis by altering the proteome and degradome. The present paper reviews previous studies of the molecular signaling pathways by which CAFs promote tumor neo-angiogenesis and highlights therapeutic response targets. Also discussed are potential strategies for antitumor neo-angiogenesis to improve tumor treatment efficacy.

Inhibition of ERK1/2 or AKT Activity Equally Enhances Radiation Sensitization in B16F10 Cells

Background

The aim of the study was to evaluate the radiation sensitizing ability of ERK1/2, PI3K-AKT and JNK inhibitors in highly radiation resistant and metastatic B16F10 cells which carry wild-type Ras and Braf.

Methods

Mouse melanoma cell line B16F10 was exposed to 1.0, 2.0 and 3.0 Gy of electron beam radiation. Phosphorylated ERK1/2, AKT and JNK levels were estimated by ELISA. Cells were exposed to 2.0 and 3.0 Gy of radiation with or without prior pharmacological inhibition of ERK1/2, AKT as well as JNK pathways. Cell death induced by radiation as well as upon inhibition of these pathways was measured by TUNEL assay using flow cytometry.

Results

Exposure of B16F10 cells to 1.0, 2.0 and 3.0 Gy of electron beam irradiation triggered an increase in all the three phosphorylated proteins compared to sham-treated and control groups. B16F10 cells pre-treated with either ERK1/2 or AKT inhibitors equally enhanced radiation-induced cell death at 2.0 as well as 3.0 Gy (P < 0.001), while inhibition of JNK pathway increased radiation-induced cell death to a lesser extent. Interestingly combined inhibition of ERK1/2 or AKT pathways did not show additional cell death compared to individual ERK1/2 or AKT inhibition. This indicates that ERK1/2 or AKT mediates radiation resistance through common downstream molecules in B16F10 cells.

Conclusions

Even without activating mutations in Ras or Braf genes, ERK1/2 and AKT play a critical role in B16F10 cell survival upon radiation exposure and possibly act through common downstream effector/s.

Cancer stem cells and signaling pathways in radioresistance

Radiation therapy (RT) is one of the most important strategies in cancer treatment. Radioresistance (the failure to RT) results in locoregional recurrence and metastasis. Therefore, it is critically important to investigate the mechanisms leading to cancer radioresistance to overcome this problem and increase patients' survival. Currently, the majority of the radioresistance-associated researches have focused on preclinical studies. Although the exact mechanisms of cancer radioresistance have not been fully uncovered, accumulating evidence supports that cancer stem cells (CSCs) and different signaling pathways play important roles in regulating radiation response and radioresistance. Therefore, targeting CSCs or signaling pathway proteins may hold promise for developing novel combination modalities and overcoming radioresistance. The present review focuses on the key evidence of CSC markers and several important signaling pathways in cancer radioresistance and explores innovative approaches for future radiation treatment.

Long-term changes in the properties of skin-derived fibroblasts following irradiation of the head and neck

The tumor stroma performs an important role in carcinogenesis. It predominantly consists of fibroblasts and the connective tissue produced by them, and undergoes a multitude of interactions with the surrounding cancer cells. Since irradiation is part of the majority of therapeutic strategies for head and neck squamous cell carcinoma, more information regarding the effects of a previous irradiation on the tumor stroma is desirable. In the present study, fibroblasts were cultivated from human non-irradiated and pre-irradiated skin of the neck for 48 h. Subsequently, analyses of cell viability, apoptosis, necrosis and motility were conducted via MTT assay, Annexin V/propidium iodide staining, electronic cell counting for 4 consecutive days, and scratch assay. Pre-irradiated fibroblasts exhibited a significantly slower growth rate as well as increased rates of apoptosis and necrosis. They also exhibited significantly decreased motility compared with non-irradiated fibroblasts. These results indicated the long-term effects of irradiation on fibroblasts, which may affect cancer recurrence in the irradiated region via the tumor stroma. More information, such as that regarding the secretory capacities of pre-irradiated fibroblasts, is required to evaluate the possible therapeutic implications of these findings.

[Preclinical models in head and neck tumors : Evaluation of cellular and molecular resistance mechanisms in the tumor microenvironment]

Because head and neck squamous cell carcinomas (HNSCC) are characterized by a distinct intertumorigenic and intratumorigenic heterogeneity, they often show substantial differences in the response to established therapy strategies. At present, a multitude of biologics and new pharmacological compounds for targeted therapies are available that allow more efficient and less toxic treatment. There is increasing pressure to establish predictive assays not only for ex ante analysis of the individual patient response to combined chemoradiotherapy and targeted therapies but also for investigation of the efficacy of new drugs. In this respect it is essential to maintain the pathophysiological tissue composition as it is known that paracrine tumor-stroma cell interactions may influence tumor reactivity to treatment. More complex models for individualized sensitivity testing have recently been described and the results are promising to pave the way for personalized cancer therapy. This review article focuses on different systems for maintaining the tumor microenvironment and hence the individual cellular composition, such as 3D organotypic models, organotypic multicellular spheroids, patient-derived xenografts and ex vivo tissue cultures and discusses the advantages and disadvantages in terms of translation into clinical application.

Differences in tumor stroma derived from irradiated versus non-irradiated fibroblasts in a co-culture model with head and neck squamous cell carcinoma

Cancer cells have a variety of interactions with neighboring connective tissue, and this activity primarily involves fibroblasts. Co-culture of fibroblasts derived from human skin with cancer cells results in the conversion of fibroblasts into cancer-associated fibroblasts, which are known to support tumor growth and invasiveness. To evaluate the effect of radiation on tumor-fibroblast interactions, the present study co-cultivated fibroblasts from pre-irradiated and non-irradiated human skin with FaDu head and neck squamous cell carcinoma cells for 3 days. Subsequently, cells were analyzed for tumor viability, apoptosis, and secretion of interleukin (IL)-6 and -8 by performing an MTT assay, Annexin V-propidium iodide test and enzyme-linked immunosorbent assay, respectively. Co-culture of FaDu cells with pre-irradiated fibroblasts resulted in a significant decrease in tumor viability, a notable increase in apoptosis and significantly lower levels of IL-8 compared with FaDu cells cultured with non-irradiated fibroblasts. Therefore, we propose that pre-irradiation changes the properties of fibroblasts and their effects on co-cultivated tumor cells, and, thus may lead to an improved understanding of the therapeutic options for patients that have already undergone irradiation.

TNF-α and IGF-1 differentially modulate ionizing radiation responses of lung cancer cell lines

The mechanism by which tumor microenvironment derived cytokine network modulates therapy response is of great concern in lung cancer but is not completely understood. In this study, we evaluated the effects of tumor necrosis factor α (TNF-α) and insulin-like growth factor 1 (IGF-1) on response of lung cancer cell lines to ionizing radiation (IR). While TNF-α increased radio sensitivity and inhibited cell migration, treatment with IGF-1 promoted cell growth and increased migration. These effects of TNF- α were mediated by increased immediate activation of stress-activated protein kinases (SAPK)/jun amino-terminal kinases (JNK) and p38. IR induced DNA damage was increased by TNF- α and not altered by IGF-1. However, in IGF-1 treated cells, there was decreased γ- H2AX along with an increase in mitotic index, resulting in abnormal chromosomal segregation in the cells. Bio informatics analysis of 982 lung cancer patients revealed that higher expression of TNF- α was associated with low risk of cancer progression while overexpression of IGF-1 was correlated with high risk. Collectively, these results reveal that the cytokines in the tumor microenvironment differentially modulate radiation therapy through a variety of signaling mechanisms.

Pirfenidone enhances the efficacy of combined radiation and sunitinib therapy

Radiotherapy is a widely used treatment for many tumors. Combination therapy using anti-angiogenic agents and radiation has shown promise; however, these combined therapies are reported to have many limitations in clinical trials. Here, we show that radiation transformed tumor endothelial cells (ECs) to fibroblasts, resulting in reduced vascular endothelial growth factor (VEGF) response and increased Snail1, Twist1, Type I collagen, and transforming growth factor (TGF)-β release. Irradiation of radioresistant Lewis lung carcinoma (LLC) tumors greater than 250 mm³ increased collagen levels, particularly in large tumor vessels. Furthermore, concomitant sunitinib therapy did not show a significant difference in tumor inhibition versus radiation alone. Thus, we evaluated multimodal therapy that combined pirfenidone, an inhibitor of TGF-induced collagen production, with radiation and sunitinib treatment. This trimodal therapy significantly reduced tumor growth, as compared to radiation alone. Immunohistochemical analysis revealed that radiation-induced collagen deposition and tumor microvessel density were significantly reduced with trimodal therapy, as compared to radiation alone. These data suggest that combined therapy using pirfenidone may modulate the radiation-altered tumor microenvironment, thereby enhancing the efficacy of radiation therapy and concurrent chemotherapy.