Absence of inflammatory response from upper airway epithelial cells after X irradiation

Predicting Radiation-Induced Lung Injury in Patients With Lung Cancer: Challenges and Opportunities

Radiation-induced lung injury (RILI) is one of the main dose-limiting toxicities in radiation therapy (RT) for lung cancer. Approximately 10% to 20% of patients show signs of RILI of variable severity. The reason for the wide range of RILI severity and the mechanisms underlying its development are only partially understood. A number of clinical risk factors have been identified that can aid in clinical decision making. Technological advancements in RT and the use of strict organ-at-risk dose constraints have helped to reduce RILI. Predicting patients at risk for RILI may be further improved with a combination of cytokine assessments, γH2AX-assays in leukocytes, or epigenetic markers. A complicating factor is the lack of an objective definition of RILI. Tools such as computed tomography densitometry, fluorodeoxyglucose-positron emission tomography uptake, changes in lung function measurements, and exhaled breath analysis can be implemented to better define and quantify RILI. This can aid in the search for new biomarkers, which can be accelerated by omics techniques, single-cell RNA sequencing, mass cytometry, and advances in patient-specific in vitro cell culture models. An objective quantification of RILI combined with these novel techniques can aid in the development of biomarkers to better predict patients at risk and allow personalized treatment decisions.

p63+Krt5+ basal cells are increased in the squamous metaplastic epithelium of patients with radiation-induced chronic Rhinosinusitis

Background

Squamous metaplasia (SM) is an irreversible form of airway epithelial remodeling. Hyperproliferation of basal cells was observed in squamous metaplastic epithelium of chronically inflamed airway. However, the association of such aberrant proliferation of basal cells with SM in the nasal epithelium after radiation damage remains unclear. The aim of this study was to investigate SM and accompanying levels of p63⁺Krt5⁺ (basal cell markers) cells in the nasal epithelium of patients with radiation-induced chronic rhinosinusitis (CRSr) and patients with chronic rhinosinusitis without nasal polyps (CRSsNP) compared to healthy controls.

Methods

We assessed the prevalence of SM and the expression of p63⁺, Krt5⁺, p63⁺Krt5⁺, and Ki67⁺ cells through immunofluorescence(IF) staining of the inferior turbinate (IT) tissues from patients with CRSr (n = 36), CRSsNP (n = 33) and controls (n = 28).

Results

The prevalence of SM and the number of p63⁺Krt5⁺ cells were both significantly increased in patients with CRSr compared to patients with CRSsNP and controls. The number of Ki67⁺ cells were both significantly increased in patients with CRSr and CRSsNP compared to controls, but the ratio of Ki67⁺ cells to p63⁺Krt5⁺ cells was significantly lower in patients with CRSr compared to patients with CRSsNP. In patients with CRSr, an increased number of p63⁺Krt5+ basal cells was observed in SM epithelium compared to non-SM epithelium.

Conclusion

SM is increased in the nasal epithelium of patients with CRSr, in which aberrant levels of p63⁺Krt5⁺ basal cells serves as an important pathologic feature in the squamous metaplastic epithelium.

Survey of pre-inflammation cytokines levels in radiotherapy-induced-mucositis

Mucositis is a toxic side effect of anti-cancer treatments and is a major focus in cancer research. Pro-inflammatory cytokines have previously been implicated in the pathophysiology of chemotherapy-induced mucositis. The aim of this study was to detect a correlation between serum cytokine levels in head and neck (H and N) cancer patients receiving combined chemo-radiation therapy. Thirty patients with H and N epithelial cancer were recruited to this study. All patients received radiotherapy to the H and N region with doses ranging from 50-70 Gray (Gy). Chemotherapy with cisplatin, carboplatin, 5-fluorouracil and taxanes was given to high-risk patients, using standard chemotherapy protocols. Patients were evaluated for mucositis according to WHO common toxicity criteria and blood samples were drawn for inflammatory (IL-1 and TNF-a) and before and during treatment. The mucositis evaluation demonstrated mucositis grade IV in 33.3% of the patients after the 3rd treatment week. At the end of treatment, the number of patients with grade IV mucositis was less. IL-1 and TNF-alpha did not show any correlation with PEG tube installation. The level of cytokines measured before and during therapy showed decreased TNF-alpha especially after the third week of therapy. No relationship between IL-1 and TNF-alpha, level and mucositis grade was shown.

Differential responses of fibroblasts, non-neoplastic epithelial cells, and oral carcinoma cells to low-level laser therapy

Low-level laser therapy (LLLT) is used in the treatment of chemoradiotherapy- or radiotherapy-induced oropharyngeal mucositis (ORM). In head and neck cancer, tumor cells may lie in the LLLT irradiation field, and LLLT might promote tumor progression. We therefore investigated the effect of LLLT on proliferation, cell cycle distribution, and apoptosis in a human oral carcinoma cell line (SCC-25), non-malignant epithelial cells (BEAS-2B), and fibroblasts in vitro. The cell lines were subjected to LLLT on three consecutive days for 15 min. Cell proliferation was assessed using the MTT assay, cell cycle distribution by flow cytometry and propidium-iodide DNA staining, and apoptosis using an Annexin V-FITC assay. Controls were sham-treated, but not exposed to the laser treatment. LLLT treatment resulted in increased fibroblast proliferation (p < 0.001), whereas decreased cell proliferation was observed after LLLT treatment of BEAS-2B (p = 0.003) and SCC-25 cells (p < 0.001). In SCC-25 cells, an increased percentage of S-phase cells and decreased percentage of G1-phase cells were observed (p < 0.001). Moreover, a proapoptotic effect of LLLT was observed in SCC-25 cells (p = 0.02). LLLT did not exhibit a tumor-promoting effect in this in vitro study.