The functional and biological effects of systemic dexamethasone on mice with facial nerve crushing injury.

BACKGROUND: Corticosteroid therapy is commonly recommended for acute facial nerve weakness; however, its effectiveness in treating traumatic nerve injuries remains controversial. This study investigated the functional recovery and cellular effects of systemic dexamethasone administration after facial nerve injury. METHODS: C57BL/6 mice were assigned to two groups by intraperitoneal injection: the phosphate-buffered saline group and the dexamethasone group. Facial nerve crush injury was induced, followed by the functional grading of recovery. Cellular effects were investigated using transmission electron microscopy, flow cytometry, immunofluorescence, and intravital imaging. RESULTS: Macrophage infiltration into the facial nerves was significantly inhibited by systemic dexamethasone administration. However, dexamethasone group slightly delayed the functional recovery of the facial nerve compared to the PBS group. In addition, the morphological changes in the nerve were not significantly different between the two groups at 14 days post-injury. Macrophage migration analysis in the intravital imaging also showed no difference between groups. CONCLUSIONS: In summary, systemic dexamethasone successfully inhibited leukocyte infiltration; however, functional recovery was delayed compared to the PBS control group. Clinically, these findings indicate that more evidence and research are required to use steroid pulse therapy for the treatment of traumatic facial nerve injuries.

Therapeutic effect of oncolytic adenovirus expressing relaxin in radioresistant oral squamous cell carcinoma.

Radioresistance is one of the main determinants of treatment outcome in oral squamous cell carcinoma (OSCC), and treatment of radioresistant OSCC is difficult due to cross resistance to other conventional treatments. We aimed to identify whether genetically modified oncolytic adenovirus expressing relaxin (RLX), which affects collagen metabolism, can effectively inhibit growth of the radioresistant OSCC. Therapeutic effect of oncolytic adenovirus was compared between radiosensitive and radioresistant OSCC cell lines in vitro and in vivo, and spread of adenovirus throughout the tumor mass was verified by immunohistochemistry (IHC). Oncolytic adenovirus effectively killed cancer cells and there was no significant difference in the cytotoxic effect between radiosensitive and radioresistant OSCC cell lines. In animal experiments, the adenovirus significantly reduced the size of tumor, and there was no significant difference between radiosensitive and radioresistant OSCC. In IHC, RLX expressing adenovirus showed better proliferation and eliminated collagens more effectively compared to RLX nonexpressing adenovirus. These findings suggested that genetically modified oncolytic adenovirus can effectively inhibit growth of the radioresistant OSCC and might be a new therapeutic option in radioresistant OSCC.

Invasive breast cancer induces laminin-332 upregulation and integrin ß4 neoexpression in myofibroblasts to confer an anoikis-resistant phenotype during tissue remodeling.

INTRODUCTION: Although development of anoikis-resistant myofibroblasts during tissue remodeling is known to be associated with tumor invasion, the mechanism by which myofibroblasts become resistant to anoikis is unknown. We previously demonstrated laminin-332 upregulation in the fibrosis around invasive ductal carcinoma (IDC). Because laminin-332 promotes cell survival through binding to integrins, we hypothesized that invasive breast cancer cells confer an anoikis-resistant phenotype on myofibroblasts by upregulating laminin-332 expression during tissue remodeling. Here, we demonstrate that invasive breast cancer cells induce laminin-332 upregulation and integrin ß4 neoexpression in myofibroblasts to confer an anoikis-resistant phenotype. METHODS: Three types of fibroblasts were isolated from the tumor burden, the fibrosis, and normal tissue of patients with early stage IDC (less than 10 mm diameter), designated cancer-associated fibroblasts (CAFs), interface fibroblasts (InFs), and normal breast fibroblasts (NBFs), respectively. To investigate direct and indirect crosstalk with tumor cells, fibroblasts were co-cultured with invasive MDA-MB-231 or noninvasive MCF7 cells or in conditioned medium. Anoikis resistance of fibroblasts was measured by cell viability and caspase-3 activity after incubation on poly-HEMA coated plates for 72 hours. Involvement of laminin-332/integrin α3ß1 or α6ß4 signaling in anoikis resistance was confirmed by treatment with purified laminin-332 or blocking antibodies against laminin-332, integrin ß1, or integrin ß4. RESULTS: MDA-MB-231 cells induced laminin-332 upregulation and integrin ß4 neoexpression in fibroblasts, leading to anoikis resistance. InFs showed a higher endogenous level of laminin-332 than did CAFs and NBFs. After stimulation with MDA-MB-231-conditioned medium, laminin-332 expression of InFs was dramatically increased and maintained under anoikis conditions. Laminin-332 upregulation was also observed in CAFs and NBFs, but at a lower level than in InFs. Laminin-332 induced Akt (Ser473) phosphorylation by binding to integrin α3ß1. Integrin ß4 neoexpression induced laminin-332-independent Rac1 activation and promoted anoikis resistance in fibroblasts approximately twofold more effectively than did laminin-332, regardless of the type of fibroblast. In addition, integrin ß4 expression suppressed fibroblast aggregation in conditions of anoikis. CONCLUSION: Invasive breast cancer cells confer an anoikis-resistant phenotype on myofibroblasts during tissue remodeling by inducing laminin-332 upregulation and integrin ß4 neoexpression. Interface fibroblasts appear to be the primary myofibroblasts that interact with invasive tumor cells during tissue remodeling.

The Time Course of Monocytes Infiltration After Acoustic Overstimulation.

Cochlea macrophages regulate cochlea inflammation and may harbors the potentials to protect hearing function from injury, including acoustic overstimulation. Cochlea macrophage numbers increase at 3-7 days after acoustic stimulation. However, the exact timing of macrophage infiltration and maturation from inflammatory monocytes is unclear. Furthermore, neutrophils may also be involved in this process. Therefore, in this study, we investigated time-dependent immune cell infiltration, macrophage transformation, and neutrophil involvement following acoustic stimulation. Flow cytometry and immunofluorescence were conducted in C-X3-C motif chemokine receptor 1 (CX3CR1)+/GFP mice after acoustic overstimulation (at baseline and at 1, 2, 3, and 5 days after exposure to 120 dB for 1 h) to identify inflammatory monocytes in the cochlea. RNA-sequencing and quantitative polymerase chain reaction were performed to identify differentially expressed genes. Inflammatory monocytes infiltrated into the lower portion of the lateral wall within 2 days after acoustic overstimulation (dpn), followed by transformation into macrophages at 3-5 dpn via CX3CR1 upregulation and Ly6C downregulation. In addition, inflammatory monocytes were aggregated inside the collecting venule only at 1 dpn. Neutrophils were not a major type of phagocyte during this response. The gene encoding C-C motif chemokine ligand 2 gene was significantly upregulated as early as 3 h after acoustic overstimulation. Given these results, treatment to control immune response after a noise-induced hearing loss should be applied as soon as possible.

LCCL peptide cleavage after noise exposure exacerbates hearing loss and is associated with the monocyte infiltration in the cochlea.

Acoustic trauma induces an inflammatory response in the cochlea, resulting in debilitating hearing function. Clinically, amelioration of inflammation substantially prevents noise-induced hearing loss. The Limulus factor C, Cochlin, and Lgl1 (LCCL) peptide plays an important role in innate immunity during bacteria-induced inflammation in the cochlea. We aimed to investigate the LCCL-induced innate immune response to noise exposure and its impact on hearing function. METHODS: We used Coch (encodes cochlin harboring LCCL peptide) knock-out and p.G88E knock-in mice to compare the immune responses before and after noise exposure. We explored their hearing function and hair cell degeneration. Moreover, we investigated distinct characteristics of immune responses upon noise exposure using flow cytometry and RNA sequencing. RESULTS: One day after noise exposure, the LCCL peptide cleaved from cochlin increased over time in the perilymph space. Both Coch-/- and CochG88E/G88E mutant mice revealed more preserved hearing following acoustic trauma compared to wild-type mice. The outer hair cells were more preserved in Coch-/- than in wild-type mice upon noise exposure. The RNA sequencing data demonstrated significantly upregulated cell migration gene ontology in wild-type mice than in Coch-/- mice following noise exposure, indicating that the infiltration of immune cells was dependent on cochlin. Notably, infiltrated monocytes from blood (C11b+/Ly6G-/Ly6C+) were remarkably higher in wild-type mice than in Coch-/- mice at 1 day after noise exposure. CONCLUSIONS: Noise-induced hearing loss was attributed to over-stimulated cochlin, and led to the cleavage and secretion of LCCL peptide in the cochlea. The LCCL peptide recruited more monocytes from the blood vessels upon noise stimulation, thus highlighting a novel therapeutic target for noise-induced hearing loss.

Panel of candidate biomarkers for renal cell carcinoma.

The timely diagnosis and therapeutic monitoring of human renal cell carcinoma (RCC) is limited by the lack of specific biomarkers. To identify candidate RCC biomarkers, we used 2-DE gel electrophoresis with mass spectrometry and 2-DE spot intensity-based ROC analysis to analyze 18 sets of paired normal and RCC tumor tissue including conventional, papillary, and chromophobe subtypes. Validation was performed with RCC patient plasma samples and confirmed by clustergram, shRNA, and immunohistochemistry assays. Cardinal candidates were evaluated by ELISA. The leading candidate biomarker that was upregulated in RCC samples according to the clustergram and validation analysis was nicotinamide N-methyltransferase (NNMT) (13/15, P < 0.0001). Other upregulated candidate biomarkers that were identified by this method include ferritin, hNSE, NM23, secretagogin, and L-plastin. The upregulation of NNMT in RCC was confirmed by immunoblotting and immunohistochemistry. Analysis of fractionated membrane-associated proteins identified CAP-G, mitofillin, tubulin alpha, RBBP7, and HSP27. Of these, RBBP7 and HSP27 were highly expressed in the chromophobe subtype of RCC (3/3) but were absent from conventional RCC (0/3). The triple combination of the NNMT, FTL, and hNSE biomarkers had the highest predictive capacity of 0.993, while NNMT was the single, most powerful candidate diagnostic biomarker for all types of RCC.

Nuclear localization of Nm23-H1 in head and neck squamous cell carcinoma is associated with radiation resistance.

BACKGROUND: Although radiation resistance is a primary issue in radiation therapy, attempts to find predictors of radiation resistance have met with little success. The authors therefore aimed to determine predictors for radiation resistance to improve the prognosis of head and neck squamous cell carcinoma (HNSCC). METHODS: HNSCC cell lines, SCC15, SCC25, and QLL1, irradiated with an acute dose of 4 grays (Gy) (RR-4), a cumulative dose of 60 Gy (RR-60), and a booster dose of 4 Gy over 60 Gy (RR-60 + 4), were used with nonirradiated cell lines. Those were used in cDNA microarray, proteomics, Western blotting, and immunofluorescence, respectively. One hundred five HNSCC tissue samples with radiation resistance were analyzed by immunohistochemistry. RESULTS: Western blot analysis of RR-60 cell lines was identical to the data of Nm23-H1 overexpression by cDNA array and proteomic screening. Immunofluorescence demonstrated significant nuclear translocation of Nm23-H1 in RR-4 and RR-60 cell lines, and less but still intense nuclear shuttling in RR-60 + 4. Similarly, Nm23-H1 nuclear localization was observed in 20% (21 of 105) of tissue samples. Univariate analysis demonstrated that Nm23-H1 nuclear localization was strongly associated with overall and recurrence-free survival. Multivariate stepwise Cox regression analysis showed that Nm23-H1 nuclear localization (odds ratio [OR], 7.48) and N stage (OR, 2.13) were associated with overall survival, and Nm23-H1 nuclear localization (OR, 3.02), T stage (OR, 1.43), and insufficient tumor margin (OR, 3.27) were associated with recurrence-free survival. CONCLUSIONS: Overexpression of Nm23-H1, specifically its nuclear translocation, may be a powerful predictor of radiation resistance in HNSCC.