The skin is constantly exposed to exogenous and endogenous sources of reactive oxygen species (ROS). An adequate balance between ROS levels and antioxidant defenses is necessary for the optimal cell and tissue functions, especially for the skin, since it must face additional ROS sources that do not affect other tissues, including UV radiation. Melanocytes are more exposed to oxidative stress than other cells, also due to the melanin production process, which itself contributes to generating ROS. There is an increasing amount of evidence that oxidative stress may play a role in many skin diseases, including melanoma, being the primary cause or being a cofactor that aggravates the primary condition. Indeed, oxidative stress is emerging as another major force involved in all the phases of melanoma development, not only in the arising of the malignancy but also in the progression toward the metastatic phenotype. Furthermore, oxidative stress seems to play a role also in chemoresistance and thus has become a target for therapy. In this review, we discuss the existing knowledge on oxidative stress in the skin, examining sources and defenses, giving particular consideration to melanocytes. Therefore, we focus on the significance of oxidative stress in melanoma, thus analyzing the possibility to exploit the induction of oxidative stress as a therapeutic strategy to improve the effectiveness of therapeutic management of melanoma.
Renal cell carcinoma (RCC) belongs to a heterogenous cancer group arising from renal tubular epithelial cells. Among RCC subtypes, clear cell renal cell carcinoma (ccRCC) is the most common variant, characterized by high aggressiveness, invasiveness and metastatic potential, features that lead to poor prognosis and high mortality rate. In addition, diagnosis of kidney cancer is incidental in the majority of cases, and this results in a late diagnosis, when the stage of the disease is advanced and the tumor has already metastasized. Furthermore, ccRCC treatment is complicated by its strong resistance to chemo- and radiotherapy. Therefore, there is active ongoing research focused on identifying novel biomarkers which could be useful for assessing a better prognosis, as well as new molecules which could be used for targeted therapy. In this light, several novel targeted therapies have been shown to be effective in prolonging the overall survival of ccRCC patients. Thus, the aim of this review is to analyze the actual state-of-the-art on ccRCC diagnosis, prognosis and therapeutic options, while also reporting the recent advances in novel biomarker discoveries, which could be exploited for a better prognosis or for targeted therapy.
5 January 2010 in Reproductive Biology and Endocrinology
Background: Early pregnancy loss can be associated with trophoblast insufficiency and coagulation defects. Thrombomodulin is an endothelial-associated anticoagulant protein involved in the control of hemostasis and inflammation at the vascular beds and it's also a cofactor of the protein C anticoagulant pathway. Discussion: We evaluate the Thrombomodulin expression in placental tissue from spontaneous recurrent miscarriage and voluntary abortion as controls. Thrombomodulin mRNA was determined using real-time quantitative polymerase chain reaction. Reduced expression levels of thrombomodulin were found in recurrent miscarriage group compared to controls (1.82-fold of reduction), that corresponds to a reduction of 45% (from control group Delta CT) of thrombomodulin expression in spontaneous miscarriage group respect the control groups. Summary: We cannot state at present the exact meaning of a reduced expression of Thrombomodulin in placental tissue. Further studies are needed to elucidate the biological pathway of this important factor in the physiopathology of the trophoblast and in reproductive biology.
We investigated expression levels of Nicotinamide N-Methyltransferase (NNMT), an enzyme Involved In the biotransformation of many drugs and xenobiotic comp
1 May 2015 in Cellular Physiology and Biochemistry
Background/Aims: Head and neck squamous cell carcinoma (HNSCC) ranks sixth worldwide for tumor-related mortality. A subpopulation of tumor cells, termed cancer stem cells (CSCs), has the ability to support cancer growth. Therefore, profiling CSC-enriched populations could be a reliable tool to study cancer biology. Methods: We performed phenotypic characterization of 7 HNSCC cell lines and evaluated the presence of CSCs. CSCs from Hep-2 cell line and HNSCC primary cultures were enriched through sphere formation and sphere-forming cells have been characterized both in vitro and in vivo. In addition, we investigated the expression levels of Nicotinamide N-methyltransferase (NNMT), an enzyme overexpressed in several malignancies. Results: CSC markers were markedly expressed in Hep-2 cell line, which was found to be highly tumorigenic. CSC-enriched populations displayed increased expression of CSC markers and a strong capability to form tumors in vivo. We also found an overexpression of CSC markers in tumor formed by CSC-enriched populations. Interestingly, NNMT levels were significantly higher in CSC-enriched populations compared with parental cells. Conclusion: Our study provides an useful procedure for CSC identification and enrichment in HNSCC. Moreover, results obtained seem to suggest that CSCs may represent a promising target for an anticancer therapy.
Oral cancer is the most common tumor of the head and neck region. Its management is based on surgical and systemic therapies. Taste disorders represent the most common side effect of these treatments; indeed, dysgeusia is noted by 70% of oral cancer patients. Despite survival remaining the primary endpoint of cancer patients, taste impairments can cause psychological distress. This comprehensive review describes the last decade’s knowledge from the literature regarding taste alterations in patients with oral and oropharyngeal squamous cell carcinoma. A total of 26 articles in English, including prospective, cross-sectional, and case–control studies, and clinical trials were evaluated. Literature analysis shows that anti-cancer treatments can destroy taste cells, decrease and alter their receptors, and interrupt nerve transmission. Furthermore, the tumour itself can destroy the oral mucosal lining, which encloses the taste buds. Dysgeusia typically occurs in 3–4 weeks of treatments, and usually taste sensation is recovered within 3–12 months. However, some patients exhibit incomplete or no recovery, even several years later. Thus, dysgeusia can become a chronic issue and negatively influence patients’ quality of life, worsening their dysphagia and their nutritional status. Physicians should be focused on preventing oncological treatment-related symptoms, offering the most suitable personalized support during therapy.