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The importance of human papillomavirus (HPV) infection and its role in the progress of cancer have been widely evaluated. The understanding of HPV association with certain cancers, such as cervical cancer, is very well established. A big step forward in the prevention of HPV associated cancers with the use of early detection by screening strategies has also been taken. In the last decade, development of HPV vaccination has reduced the number of cases in HPV infections and infection induced cancers. In this report, we review the HPV pathogenesis and highlight the mechanism of HPV involvement in cancer development.

Purpose The aim of the study is to investigate the regulation of DNA repair genes by microRNAs (miRNAs). miRNAs are short non-coding RNAs that regulate transcriptional and post-transcriptional gene silencing. Several miRNAs that are expressed during preimplantation embryo development have been shown or are predicted to target genes that regulate cell cycle checkpoints and DNA repair in response to DNA damage. Methods This study compares the expression level of 20 miRNAs and 9 target transcripts involved in DNA repair. The statistical significance of differential miRNA expression between oocytes and blastocysts was determined by t test analysis using the GraphPad Prism v6 software. The possible regulatory roles of miRNAs on their target messenger RNAs (mRNAs) were analysed using a Pearson correlation test. Results This study shows for the first time that several miRNAs are expressed in human oocytes and blastocysts that target key genes involved in DNA repair and cell cycle checkpoints. Blastocysts exhibited statistically significant lower expression levels for the majority of miRNAs compared to oocytes (p<0.05). Correlation analyses showed that there was both inverse and direct association between miRNAs and their target mRNAs. Conclusions miRNAs target many mRNAs including ones involved in DNA repair mechanisms. This study suggests that miRNAs and their target mRNAs involved in DNA repair are expressed in preimplantation embryos. Similar to the miRNAs expressed in adult tissues, these miRNAs seem to have regulatory roles on their target DNA repair mRNAs during preimplantation embryo development.

Background/aim: This study analyzed the incidence, trends, and common types of cancer in the Turkish Republic of Northern Cyprus (TRNC). Materials and methods:This study is based on data collected from the office of the North Cyprus Cancer Registry, Ministry of Health, for 2007-2012. Data were arranged on the basis of age group, sex, and cancer site. Age standardized incidence rates (ASRs) were estimated with the world standard population. EVIEWS (version 9) software was used for statistical analysis.Results: Of 1395 registered cases, 52.33% (730) were reported in men and 47.67% (665) in women. The crude incidence rate was 96.41 in men and 101.74 in women. The average annual ASR was 88.88 in men and 87.76 in women with the cumulative rate of 21.47% and 14.69% in men and women, respectively. The most common cancers in men were skin (ASR 15.62), prostate (ASR 11.23), bladder (ASR 11.71), lung (ASR 8.01), and colorectal cancer (ASR 7.61), while in women these were breast (ASR 24.07), thyroid (ASR 14.93), skin (ASR 10.75), colorectal (ASR 6.05), and lymphoma (ASR 4.79). Linear regression analysis confirmed rising trends for both men's (10.79, P ≤ 0.03) and women's (14.67, P ≤ 0.04) cancers. Conclusion:Our findings revealed an increasing trend of cancer incidence in the TRNC. For control and prevention, public awareness of the risk factors and proper screening programs should be recommended.

Active DNA repair pathways are crucial for preserving genomic integrity and are likely among the complex mechanisms involved in the normal development of preimplantation embryos. MicroRNAs (miRNA), short non-coding RNAs, are key regulators of gene expression through the post-transcriptional and post-translational modification of mRNA. The association of miRNA expression with infertility or polycystic ovarian syndrome has been widely investigated; however, there are limited data regarding the importance of miRNA regulation in DNA repair during preimplantation embryo development. In this article, we review normal miRNA biogenesis and consequences of aberrant miRNA expression in the regulation of DNA repair in gametes and preimplantation embryos.

Human papillomaviruses (HPVs)-small, nonenveloped viruses with double-stranded circular DNA-are believed to have a role in the progression of cancer. However, the exact mechanisms are not well established. The interference of HPV proteins, especially E6 and E7, in the cell cycle is considered to be the main pathway. It is still questioned whether the expression of these proteins or the viral load is more important in neoplastic transformation. Furthermore, HPV is believed to adapt mechanisms to evade the host cell immune system; persistent HPV infection may also play a role in oncogenic transformation by causing genomic instability and local immune suppression. These factors may cause accumulation of genomic alterations within the host cell and integration of the viral genome into the host genome. In recent years, epigenetic modifications, such as methylation, have also been considered to take part in neoplastic transformation. All of these alterations to the genome may be favorable to the development of cancer. This article highlights the association of HPV in neoplastic transformation and cancer progression.

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Breast cancer has continued to be a cause of increasing morbidity and mortality in women, being the most common cause of cancer-related deaths among them. Its management using chemotherapy is continually plagued with problems of systemic toxicity, lack of compliance by patients, and inadequate targeting of cancer cells. The future of breast cancer chemotherapy will likely involve the use of biocompatible high cell-targeting capacity drug-delivery vehicles like silk fibroin to ameliorate these problems. The utilization of silk fibroin nanoparticles to deliver cytotoxic drugs provides specificity, optimal entrapment, improved therapeutic index, and maximal breast cancer cell toxicity with minimal or no collateral damage to surrounding normal cells. The silk fibroin obtained from the cocoon of the Bombyx morii worm is processed and degummed to remove the sericin component; it is then made into nanoparticles utilizing the desolvation, ionic gelation, or electrospray method. It is then loaded with an appropriate chemotherapeutic drug (e.g., carboplatin), and characterization is performed using physico-chemical methods such as fourier-transform infrared spectroscopy, dynamic light scattering, or transmission electron microscopy. The nanoparticles are then tested for cytoxicity, and the induction of apoptosis on breast cancer cell lines MC-7 (Her2-) and MDA-MB-453 (Her2+). Toxicity and apoptosis are assessed using the MTT assay and ELISA methods, respectively. Silk fibroin has been demonstrated in various studies to be a very useful tool in specific active or passive drug delivery to target cancer cells, thus ensuring a maximum destruction and minimum damage to normal surrounding cells, which decreases systemic toxicity and enhances drug efficacy.