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Collagen has shown promising potential in biomedical fields due to its high biocompatibility, abundance of resources, ease of flexible modification, and potential for active targeting. The biomedical capacity is largely influenced by their unique structure and properties. Collagen is typically extracted from tissues and organs that are commonly discarded as waste. The extraction of collagen from agricultural and sideline resources is an environmentally friendly method for utilizing byproducts and generating high-value products. The extraction methods can significantly impact the structure and composition. Collagens can be cross-linked using external reagents or techniques to enhance their strength and meet growing demands. This review will discuss the recent advancements in collagen-based biomaterials for chronic wound healing, bone regeneration, and cornea defect repair, focusing on extraction and modification strategies. We are dedicated to bridging the gap between the pretreatment of collagens in various processes and their specific applications. This will facilitate the scientific design and optimal utilization of collagen-based biomaterials for tissue regeneration. This review provides readers with a comprehensive understanding of the advancements in extraction methods, cross-linking strategies, and the biomedical applications of collagen. [ABSTRACT FROM AUTHOR]

Background: Basal cell carcinoma (BCC) is the most common type of skin cancer with an increasing incidence worldwide that imposes a considerable burden on public health. C-X-C chemokine receptor (CXCR4) plays a vital role in initiation, progression and metastasis of several types of cancers. The aim of the present study was to investigate the expression and clinical significance of CXCR4 in BCC. Methods: In this study, 80 samples of primary BCC were assessed for CXCR4 expression using immunohistochemistry. The mRNA and protein expression levels of CXCR4 were evaluated by real-time reverse transcription polymerase chain reaction and Western blot analysis, respectively. Results: CXCR4-positive staining was detected in 70% of BCC samples. Overexpression of CXCR4 was significantly associated with tumor size (>2 vs. 2 cm, p = 0.002) and pathological type (invasive vs. noninvasive, p = 0.007). CXCR4 was also upregulated at transcriptional and translational levels. Conclusion: Our study revealed that the expression of CXCR4 was associated with progression and invasion in patients with BCC. It may be a considerable biomarker to assess invasiveness of nasal-surface BCC and to guide clinical management of such tumors. © 2014 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Paclitaxel has been proved to be active in treatment and larynx preservation of HNSCC, however, the fact that about 20-40% patients do not respond to paclitaxel makes it urgent to figure out the biomarkers for paclitaxel-based treatment in Hypopharynx cancer (HPC) patients to improve the therapy effect. In this work, Fadu cells, treated or untreated with low dose of paclitaxel for 24 h, were applied to DNA microarray chips. The differential expression in mRNAs and miRs was analyzed and the network between expression-altered mRNAs and miRs was constructed. Differentially expressed genes were mainly enriched in superpathway of cholesterol biosynthesis (ACAT2, MSMO1, LSS, FDFT1 and FDPS etc.), complement system (C3, C1R, C1S, CFR and CFB etc.), interferon signaling (IFIT1, IFIT3, IFITM1 and MX1 etc.), mTOR signaling (MRAS, PRKAA2, PLD1, RND3 and EIF4A1 etc.) and IGF1 signaling (MRAS, IGFBP7, JUN and FOS etc.), most of these pathways are implicated in tumorigenesis or chemotherapy resistance. The first three pathways were predicted to be suppressed, while the last two pathways were predicted to be induced by paclitaxel, suggesting the combination therapy with mTOR inhibition and paclitaxel might be better than single one. The dramatically expression-altered miRs were miR-112, miR-7, miR-1304, miR-222*, miR-29b-1* (these five miRs were upregulated) and miR-210 (downregulated). The 26 putative target genes mediated by the 6 miRs were figured out and the miR-gene network was constructed. Furthermore, immunoblotting assay showed that ERK signaling in Fadu cells was active by low dose of paclitaxel but repressed by high dose of paclitaxel. Collectively, our data would provide potential biomarkers and therapeutic targets for paclitaxel-based therapy in HPC patients.

Paclitaxel is a widely used chemotherapy drug for advanced laryngeal cancer patients. However, the fact that there are 20-40% of advanced laryngeal cancer patients do not response to paclitaxel makes it necessary to figure out potential biomarkers for paclitaxel sensitivity prediction. In this work, Hep2, a laryngeal cancer cell line, untreated or treated with lower dose of paclitaxel for 24 h, was applied to DNA microarray chips for gene and miR expression profile analysis. Expression of eight genes altered significantly following paclitaxel treatment, which was further validated by quantitative real-time PCR. Four up-regulated genes were ID2, BMP4, CCL4 and ACTG2, in which ID2 and BMP4 were implicated to be involved in several drugs sensitivity. While the down-regulated four genes, MAPK4, FASN, INSIG1 and SCD, were mainly linked to the endoplasmic reticulum and fatty acid biosynthesis, these two cell processes that are associated with drug sensitivity by increasing evidences. After paclitaxel treatment, expression of 49 miRs was significantly altered. Within these miRs, the most markedly expression-changed were miR-31-star, miR-1264, miR-3150b-5p and miR-210. While the miRs putatively modulated the mRNA expression of the most significantly expression-altered genes were miR-1264, miR-130a, miR-27b, miR-195, miR-1291, miR-214, miR-1277 and miR-1265, which were obtained by miR target prediction and miRNA target correlation. Collectively, our study might provide potential biomarkers for paclitaxel sensitivity prediction and drug resistance targets in laryngeal cancer patients.

Objective: To investigate the expression of hypoxia-inducible factor-1alpha (HIF-1alpha) and cyclooxygenase-2 (COX-2) in laryngeal squamous cell carcinoma (LSCC), while determine their relationship with clinicopathologic characteristics and prognosis., Methods: Tumor tissues were obtained from 60 patients who underwent resection of laryngeal carcinoma in Affiliated First People's Hospital of Shanghai Jiaotong University. Immunohistochemistry (Envision DAKO) was used to detect the expressions of HIF-1alpha and COX-2 in the tumor tissues. As control group, 15 cases of atypical hyperplasia, 10 cases of leukoplakia of vocal cord and 10 cases of polyp of vocal cord were studied. All patients were regularly followed up and the clinical data were collected systematically., Results: Positive staining rates of HIF-1alpha and COX-2 were 95.0% (57/60) and 98.3% (59/60), respectively in all 60 specimen of LSCC. The positive expressions in LSCC were significantly higher than those in atypical hyperplasia, leukoplakia and polyp of vocal cord ( Fisher's exact test, P < 0.01). The expression of HIF-1alpha was correlated with COX-2 in LSCC (r = 0.526, P < 0.01). High level expressions of HIF-1alpha and COX-2 were 35.0% (21/60) and 38.3% (23/60) respectively. High level expression of HIF-1alpha was significantly correlated with clinical stages (chi2 = 4.331, P < 0.05) and lymph nodes metastases (Fisher's exact test, P < 0.05). High level expression of COX-2 was significantly correlated with clinical stage (chi2 = 8.539, P < 0.01) and T stages (chi2 = 6.792, P < 0.01). With univariate analysis, high level expressions of HIF-1alpha and COX-2 were significantly associated with a worse overall survival (chi2 = 6.003, P < 0.05 and chi2 = 9.489, P < 0.01, respectively) and disease-free survival (chi2 = 5.010, P < 0.05 and chi2 = 6.102, P < 0.05, respectively). With multivariate analysis, recurrence and high level expression of COX-2 were two unfavorable prognostic factors (RR = 7.104, P = 0.003; RR = 5.714, P = 0.008)., Conclusions: The expressions of HIF-1alpha and COX-2 played an important role in the process of tumorigenesis and development of LSCC, The expression of HIF-1alpha was correlated with COX-2 in LSCC. COX-2 and recurrence were probably significant risk factors for prognosis of LSCC.