Role of non-coding RNA networks in leukemia progression, metastasis and drug resistance.

Early-stage detection of leukemia is a critical determinant for successful treatment of the disease and can increase the survival rate of leukemia patients. The factors limiting the current screening approaches to leukemia include low sensitivity and specificity, high costs, and a low participation rate. An approach based on novel and innovative biomarkers with high accuracy from peripheral blood offers a comfortable and appealing alternative to patients, potentially leading to a higher participation rate.Recently, non-coding RNAs due to their involvement in vital oncogenic processes such as differentiation, proliferation, migration, angiogenesis and apoptosis have attracted much attention as potential diagnostic and prognostic biomarkers in leukemia. Emerging lines of evidence have shown that the mutational spectrum and dysregulated expression of non-coding RNA genes are closely associated with the development and progression of various cancers, including leukemia. In this review, we highlight the expression and functional roles of different types of non-coding RNAs in leukemia and discuss their potential clinical applications as diagnostic or prognostic biomarkers and therapeutic targets.

Recent Advances in Head and Neck Tumor Microenvironment-Based Therapy.

Head and neck squamous cell carcinomas (HNSCCs) are a group of heterogeneous aggressive tumors affecting more than half a million patients worldwide annually. While the tobacco- and alcohol-associated HNSCC tumors are declining, human papillomavirus (HPV)-induced tumors are on rise. Despite recent advances in multimodality therapeutic interventions including surgery in combination with chemoradiation therapy (CRT), the overall 5-year survival has not improved more than 50%. The underlying reasons for this dismal prognosis is the intrinsic or acquired resistance to CRT. While previous studies were focused to target tumor cells, recent findings have implicated the involvement of tumor microenvironment (TME) on tumor progression and response to therapy. HNSCC TME includes cancer-associated fibroblasts (CAFs), endothelial cells, immune cells, endocrine cells, and the extracellular matrix (ECM) proteins including collagen and fibronectin. Understanding the crosstalk between TME and cancer cells is important to formulate more effective novel therapies and to overcome resistance mechanisms. Here, we summarized the current literature on recent advances on HNSCC TME with special emphasis on novel cell-cell interactions and therapies currently under development.

P66Shc-rac1 pathway-mediated ROS production and cell migration is downregulated by ascorbic acid.

The oxidative role(s) of p66Shc protein has been increasingly expanded over the last decade. However, its relation with the most potent antioxidant molecule, i.e. ascorbic acid has never been studied. We have previously shown that p66Shc mediates rac1 activation, reactive oxygen species (ROS) production and cell death. Here we studied the effect of ascorbic acid on the pathway involving p66Shc and rac1. Our results indicate a decrease in the expression of p66Shc in a dose- and time-dependent manner. We studied the effect of ascorbic acid on rac1 expression and its activity. Ascorbic acid has no effect on total rac1 expression; however, rac1 activation was inhibited in a dose-dependent manner. Results suggest that the decrease in rac1 activity is mediated through ascorbic acid-modulated p66Shc expression. The decrease in rac1 activity was evident in cells transfected with the p66shc mutant (proline motif mutant, at residues P47 to P50). Our studies indicate that p66Shc-mediated ROS upregulation is significantly decreased in the presence of ascorbic acid. Cell migration experiments point towards the inhibition of p66Shc-rac1-mediated migration in the presence of ascorbic acid. Finally, results are suggestive that ascorbic acid-mediated decrease in Shc expression occurs through an increased Shc ubiquitination. Overall, the study brings out the novel role of ascorbic acid in antioxidant signal transduction.

Association of -675 4G/5G PAI-1 and -2518A/G MCP-1 genetic polymorphisms with polycystic ovary syndrome in Kashmiri women: A case control study.

Background: Polycystic ovarian syndrome (PCOS) is a highly prevalent endocrine disorder among females of fertile age. It has been speculated to be associated with low-grade chronic inflammation like other inflammatory response-driven multifactorial illnesses such as diabetes mellitus (DM) and cancer. Monocyte chemoattractant protein-1 (MCP-1) and plasminogen activator inhibitor-1 (PAI-1) are biomarkers of inflammation and endothelial dysfunction, respectively. These have been found to be elevated in PCOS patients. The current research reveals that single nucleotide polymorphisms (SNPs) in their genes are strongly associated with the elevation of these biomarkers. The goal of this study was to see if there was a link between PAI-1 -675 4G/5G and MCP-1 -2518 A/G polymorphisms with the occurrence of PCOS. Material and Method: This study included 220 PCOS participants and 220 healthy controls. The allele-specific polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) methods were used to investigate PAI-1-675 4G/5G and MCP-1 -2518A/G SNPs, respectively. Results: The -675 4G/5G SNP in the PAI-1 gene was strongly linked to PCOS. The odds ratio (OR) for the 4G/4G genotype was (OR = 3.2; P = 0.001), whereas the OR for the 4G/5G genotype was (OR = 2.39; P = 0.001). The carriers with the 4G/4G and 4G/5G genotypes showed significantly increasing trends in the triglyceride levels (P < 0.05). The genotypic frequency of the -2518 A/G MCP-1 SNP differed significantly between the PCOS patients and healthy controls; the GG genotype remained a strong predictor of PCOS (OR = 8.7; P = 0.01) and the AG genotype (OR = 2.40; P = 0.01), indicating an elevated risk of predisposing women to PCOS. There was a significant variation in the glucose 2-h levels between -2518A/G MCP-1 genotypes with AG heterozygous and GG mutant genotype showing increasing trends of glucose 2-h levels (P < 0.05). Conclusion: Both PAI-1 -675 4G/5G and MCP-1 -2518A/G polymorphisms are associated with predisposition to PCOS and its complications in Kashmiri women.

P66shc and its downstream Eps8 and Rac1 proteins are upregulated in esophageal cancers.

Members of Shc (src homology and collagen homology) family, p46shc, p52shc, p66shc have known to be related to cell proliferation and carcinogenesis. Whereas p46shc and p52shc drive the reaction forward, the role of p66shc in cancers remains to be understood clearly. Hence, their expression in cancers needs to be evaluated carefully so that Shc analysis may provide prognostic information in the development of carcinogenesis. In the present study, the expression of p66shc and its associate targets namely Eps8 (epidermal pathway substrate 8), Rac1 (ras-related C3 botulinum toxin substrate1) and Grb2 (growth factor receptor bound protein 2) were examined in fresh tissue specimens from patients with esophageal squamous cell carcinoma and esophageal adenocarcinoma using western blot analysis. A thorough analysis of both esophageal squamous cell carcinoma and adenocarcinoma showed p66shc expression to be significantly higher in both types of carcinomas as compared to the controls. The controls of adenocarcinoma show a higher basal expression level of p66shc as compared to the controls of squamous cell carcinoma. The expression level of downstream targets of p66shc i.e., eps8 and rac1 was also found to be consistently higher in human esophageal carcinomas, and hence correlated positively with p66shc expression. However the expression of grb2 was found to be equal in both esophageal squamous cell carcinoma and adenocarcinoma. The above results suggest that the pathway operated by p66shc in cancers does not involve the participation of Ras and Grb2 as downstream targets instead it operates the pathway involving Eps8 and Rac1 proteins. From the results it is also suggestive that p66shc may have a role in the regulation of esophageal carcinomas and represents a possible mechanism of signaling for the development of squamous cell carcinoma and adenocarcinoma of esophagus.

Review of the current knowledge on the epidemiology, pathogenesis, and prevention of human papillomavirus infection.

Human papillomavirus (HPV) infection is a central and necessary, although not sufficient, cause of cervical cancer. Besides HPV, the additional multiple risk factors related with the onset of cervical cancer are early-age sexual activities; high number of sexual partners, which is the most salient risk factor; suppression and alteration of the immune status; long-term use of oral contraceptives; and other hormonal influences. The tumor-suppressor proteins p53 and pRb are degraded and destabilized through ubiquitination by viral oncoproteins E6 and E7. Over 95% of cervical cancer cases worldwide test positive for oncogenic HPV DNA. Although cervical screening procedures have been successful in reducing the disease burden associated with HPV infection because of lack of resources or inadequate infrastructure many countries have failed to reduce cervical cancer mortality. Therefore, prevention may be a valuable strategy for reducing the economic and disease burden of HPV infection. At present, two successful prophylactic HPV vaccines are available, quadrivalent (HPV16/18/6/11) 'Gardasil' and bivalent (HPV16/18) 'Cervarix' for vaccinating young adolescent girls at or before the onset of puberty. Recent data indicate that vaccination prevents the development of cervical lesions in women who have not already acquired the vaccine-specific HPV types. Moreover, several therapeutic vaccines that are protein/peptide-based, DNA-based, or cell-based are in clinical trials but are yet to establish their efficacy; these vaccines are likely to provide important future health benefits. The therapeutic vaccination mode of prevention is a promising area of research, as revealed in preclinical trials; however, clinical trials based on large populations are warranted before reaching a valid conclusion. This review summarizes the studies on the epidemiology of HPV infection, the pathogenesis of viral oncoproteins in the oncogenesis of cervical cancer, the economic and health burden of HPV-related diseases, and, finally, focuses on the results of recent clinical vaccination trials.

Molecular linkages between diabetes and Alzheimer's disease: current scenario and future prospects.

After the revolutionary Rotterdam study that suggested there was an increased risk of developing Alzheimer's disease (AD) in patients with type-2 diabetes mellitus (T2DM), a number of studies have provided direct evidence for the linkage between AD and T2DM. In recent years, AD is considered as a neuroendocrine disorder, also referred as type-3 diabetes. There is a growing list of evidence to suggest that, in addition to impaired insulin signaling, there are a number of additional factors that may act as mechanistic links between AD and T2DM. These factors mainly include hypercholesterolemia, dyslipidemia, hypercystinemia, inflammation, impaired insulin signaling and impaired central nervous response to the adipose tissue-derived hormone leptin. Increased cholesterol plays a crucial role in the abnormal metabolism of the amyloid precursor protein, leading to the accumulation of ß-amyloid. In addition to impaired insulin signaling, diabetes has been found to accelerate the appearance of cerebrovascular inflammation and ß-amyloid peptide (Aß) deposition. Increased oxidative stress and production of advanced glycation end products are other probable marker linkages. However, the details of many of these molecular links still require extensive investigation. It is possible that a number of common molecular linkages exist between T2DM and AD. Understanding and analyzing the various molecular linkages between AD and T2DM may shed light on new tools that can be used for the early diagnosis and treatment of AD and also accelerate the identification of T2DM patients who are at high risk of AD.

Phytochemical screening, physicochemical properties, acute toxicity testing and screening of hypoglycaemic activity of extracts of Eremurus himalaicus baker in normoglycaemic Wistar strain albino rats.

In the present study EtOAc, MeOH, and aqueous extracts of Eremurus himalaicus were evaluated for hypoglycaemic effect in normal rats using both oral glucose tolerance test and 14-day oral administration study. Phytochemical and physicochemical screening was also done. In oral glucose tolerance test the aqueous and MeOH extracts of Eremurus himalaicus at a dose level of 500 mg/kg body weight prior to glucose load resulted in a significant fall in blood glucose level within 150 min. of glucose administration. The aqueous extract at a dose level of 250 mg/kg body weight and 500 mg/kg body weight also showed good hypoglycaemic response (P < 0.001); this was followed by MeOH extract at a dose level of 500 mg/kg body weight (P < 0.05), while MeOH extract at dose level of 250 mg/kg body weight and ethyl acetate extract at dose level of 250 mg/kg body weight and 500 mg/kg body weight exhibited insignificant effect. Phytochemical screening of extracts revealed the presence of alkaloids, terpenoids, phenolics, tannins, saponins, cardiac glycosides, and flavonoids. The results indicate that aqueous extract possess significant hypoglycaemic activity in normoglycaemic rats which may be attributed to the above-mentioned chemical constituents.