Ion channels and their role in chemo-resistance.

Ion channels play a crucial role in cellular signaling, homeostasis, and generation of electrical and chemical signals. Aberrant expression and dysregulation of ion channels have been associated with cancer development and resistance to conventional cancer treatment such as chemotherapy. Several molecular mechanisms have been proposed to explain this phenomenon. Including evasion of apoptosis, decreased drug accumulation in cancer cells, detoxifying and activation of alternative escape pathways such as autophagy. Each of these mechanisms leads to a reduction of the therapeutic efficacy of administered drugs, causing more difficulty in cancer treatment. This review highlights the linkages between ion channels and resistance to chemotherapy. Furthermore, it elaborates their molecular mechanisms and the potential of being therapeutic targets in clinical management.

Epidemiologic and histopathological evaluation of unclassified gingival papules in Urmia, Iran.

Objectives: Unclassified gingival papules might be mistaken with other malignant lesions as they resemble some other oral lesions. The present study demonstrates epidemiologic and histopathological characteristics of the gingival unclassified papules in the patients referred to Urmia Dental School, Iran. Materials and Methods: A cross sectional descriptive study design was conducted among 500 pateints in Urmai university of medical sciences, Iran. The participant's demographic data and medical history were obtained using clinical examinations and a questionnaire. Histopathological assessments were done in two specimens. The effect of the possible factors on the incidence of gingival papules was statistically assessed by Fisher's exact test. Results: Among 500 participants, 340 (68%) demonstrated unclassified gingival papules (40.9% males, 59.1% females; mean age of 34.9 years). No significant differences were found regarding the effect of gender, smoking, mouth breathing, history of skin disease or pregnancy on the incidence of gingival papules. However, the breastfeeding females (P < 0.004) or those using contraceptive pills (P < 0.02) showed lower frequency of papules' incidence. Among 340 papules, 332 (97.6%) were white in color, 337 (99.1%) were well defined and 331 (97.3%) were observed in the keratinized gingiva. 207 (60.9%) were multiple and 133 (39.1%) were single lesions. The papules showed healthy tissues similar to gingival tissue; however, abundant collagen bundles were irregular and close to the surface, which was covering by stratified squamous epithelium. Conclusion: Gingival papules are common findings in patients referring to Urmia Dental School; the lesions were almost white in color, well defined and appeared in the keratinized gingiva. The lesions were a variation of normal oral structures with no treatment requirements.

Evaluation of HER2/neu expression in different types of salivary gland tumors: a systematic review and meta-analysis.

This study is a systematic review and meta-analysis to assess the overexpression rate of HER2 in patients with salivary gland tumors. We included peer-reviewed publications from 1995 to 2020, indexed in medical databases, using search terms such as "human epidermal growth factor receptor 2 (HER2)" and "salivary gland tumors", and extracted relevant data. The extracted data were analyzed with RevMan 5.3 software. Intra-and intergroup post hoc analyses of outcome variables were performed using t-tests, and the rates of HER2 positivity among studies were evaluated. 80 studies were included in the analysis. The positive rates of HER2 ranged from 3.3% to 84.0% and 1% to 9% in malignant and benign subtypes, respectively. The highest HER2 overexpression rate among malignant tumors was in salivary ductal carcinomas (SDC), with a 45% positive rate (CI 95%: 21.9-70.3%). Mucoepidermoid carcinoma (MEC) had the highest positive rate of 84% (CI 95%: 74.1-90.0%). Among benign salivary gland tumors, the highest rate was found in myoepithelioma, with a positive rate of 9% (CI 95%: 1.7-33.6%). The highest rate of HER2 overexpression is present in malignant subtypes of salivary gland tumors, more specifically in salivary ductal carcinoma, mucoepidermoid carcinomas, salivary duct carcinoma in situ, and carcinoma ex pleomorphic adenoma.

Current Definitions and Clinical Implications of Biomarkers in Graft-versus-Host Disease.

Hematopoietic cell transplantation (HCT) is a potentially curative treatment for many hematologic and nonhematologic disorders. Graft-versus-host-disease (GVHD) in its acute or chronic form remains the most important nonrelapse post-HCT complication. Biomarkers offer objective, unbiased information on systemic disorders, and significant attention has focused on identifying biomarkers for GVHD. Ideally, a GVHD biomarker is actionable, with the results of biomarker testing used to guide clinical management of disease and clinical trial design. Although many GVHD biomarkers have been identified, none have been properly qualified for clinical use. The National Institutes of Health (NIH) and Food and Drug Administration (FDA) have provided biomarker subtype definitions; however, confusion remains about the proper definition and application of these subtypes in the HCT field. The 2014 NIH consensus development project provided a framework for the development of biomarkers for clinical practice. This review aims to clarify the biomarker subtype definitions and reemphasize the developmental framework. Armed with this knowledge, clinicians can properly translate GVHD biomarkers for clinical use.

Selenium-Enriched Saccharomyces cerevisiae Reduces the Progression of Colorectal Cancer.

Colorectal cancer is one of the most common causes of mortality in the world while malnutrition is responsible for one third of the problem. Selenium has been recommended for prevention of colorectal cancer. The present study was conducted to investigate the effect of selenium-enriched Saccharomyces cerevisiae in reducing colorectal cancer progression in rats. Five groups of 170-200-g weight rats (n = 40) including healthy and cancer controls, Saccharomyces cerevisiae, selenium, and selenium-enriched Saccharomyces cerevisiae-treated groups were examined. All animals except healthy control group received 40 mg 1,2-dimethylhydrazine (DMH) per kilogram weight of rat twice a week. The healthy group received normal saline, and synchronously, selenium group received soluble selenium (4 mg/mL), Saccharomyces cerevisiae and selenium-enriched groups received yeast with the density of 5 × 108 CFU/mL by daily gavage. All treatments were carried out for 5 weeks after the last injection. Animals were autopsied, and aberrant crypt foci (ACF) of ejected colon were studied in the 40th week. Microscopic sections were prepared for hematoxylin and eosin. Furthermore, immunohistochemical staining of CD31, BCL2, and P53 antibodies was performed. Macroscopic and microscopic evaluations showed that DMH had the least destructive effect in selenium-enriched Saccharomyces cerevisiae group compared to other groups. Selenium-enriched Saccharomyces cerevisiae reduces colorectal cancer progression by various mechanisms such as reduction in the number and size of ACF and alteration in the function of the proteins such as P53, BCL2, and CD31.