Cytoplasmic L1 Levels in Cancer

In addition to shaping genome diversification over evolutionary time, L1 retrotransposition alters gene expression as well. The most notable gene altering process involves insertional mutagenesis. The aim of the study was the examination of both nuclear L1 expression levels and cellular localization in cancer cell lines, PBMCs from healthy volunteers and PBMCs from cancer patients. L1 was detected by FISH in chromosome preparations. L1 probe was custom-made using end-point PCR against L1-ORF2 and conjugated with FITC. It was found that cancer cell lines and clinical samples from cancer patients contained significantly elevated levels of L1 per nucleus compared to healthy volunteers. Cytoplasmic L1 was also increased in the above mentioned samples denoting that cancer could be associated with increased L1 activation and mobility. Our results may provide a novel cancer diagnostic marker and highlight the possibility of cytoplasmic L1 inhibition as a therapeutic intervention for cancer.

Efficacy of 5-FU or Oxaliplatin Monotherapy over Combination Therapy in Colorectal Cancer

Recent clinical and research development supports the use of 5-fluorouracil in combination with oxaliplatin for the treatment of patients with advanced colorectal cancer (CRC). 5-Fluorouracil (5-FU), which is as an anti-metabolite, is a widely used cytostatic drug. Although the rate of response, quality of life and overall survival differs between CRC patients, the above combination remains a widely used chemotherapeutic regimen. In some cases, a cancer stem cell (CSC) population may resist the majority of chemotherapeutic models. This study investigated if monotherapy is more efficacious than 5-fluorouracil and oxaliplatin combined for the treatment of CRC, using a CRC cell line and a CSC-like line. Cell viability was evaluated by cellular-based assays, and quantitative polymerase chain reaction (q-PCR) assays were performed to assess the expression of specific genes (TYMS,?DNMT1,?NANOG, DHFR, SHMT1, ERCC1, DPYD) correlated with 5-FU and oxaliplatin resistance. We observed that 5-fluorouracil was more effective in both CRC and CSCs. This finding proved the hypothesis that, in some cases, monotherapy may be more successful in CRC treatment than a drug combination that may be cytotoxic and inflict adverse side effects.

Flow Cytometric Detection of Circulating Tumor Cells in Breast Cancer Patients: A Blinded Study

Circulating tumor cells are cells that detach from the primary tumor site and migrate to the bone marrow or other tissues where they can initiate a metastatic site. Liquid biopsies are an emerging tool in the past decades that enables us to detect Circulating Tumor Cells in patients’ blood. Flow cytometry is a powerful tool used in liquid biopsy diagnostics. This aims to prove the sensitivity and specificity of a flow cytometric panel for the detection of CTCs in breast cancer patients using healthy individuals’ samples as controls. The study was blinded to the data analyzing researcher. Statistical analysis followed and results show 86.9% area under the curve which indicates that the particular method can be very promising for diagnosing breast cancer.

Stemness Gene Profiles of Circulating Tumor Cells

Circulating tumor cells (CTCs) are a population of tumor-derived cells that detach from the primary tumor and initiate metastasis. However, the mechanisms of this process are still unknown. This phenomenon renders CTCs as a valuable resource for prognosis and diagnosis of cancer. The involvement of stemness transcription factors and markers, such as NANOG, OCT3/4, CD34, NESTIN, and SOX2, in metastasis initiation has been studied recently because their abnormally elevated expression in cancer cells may be highly important in understanding tumor initiation. This study analyzed the genetic profiles of the above genes in CTCs derived from patients with different types of cancer. Blood samples were randomly collected from 71 cancer patients with various cancer types. CTCs were isolated using enrichment protocols and RNA was extracted. RT-qPCR was performed in triplicate using ACTB as the reference gene. The statistical analysis was performed among the ΔCts of the samples using parametric and non-parametric methods. The molecular analysis revealed that the expression of each gene was different than the others. When each type of cancer was analyzed separately, the gene expression profile was not always the same. It is noteworthy that, in all cases, the gene expression of NESTIN differed from that of transcription factors. According to the above data, gene expression profiles might be used as a potential biomarker or constitute a gene signature.

Array Comparative Genomic Hybridization as a Diagnostic Tool in Cancer

The knowledge of the primary origin of tumor is essential in designing an efficient cancer treatment algorithm. Useful diagnostic tools enable determination of primary origin of the tumor;however the majority of them require tissue examination. Recent years, exploration of circulating tumor cells enabled scientists to study different parameters using the painless liquid biopsy. The present study aimed to identify whether aCGH might be used as a diagnostic tool in cancer detecting the primary origin of the tumor. Blood was extracted from healthy individuals and cancer samples and CTCs isolated. DNA extracted from the above samples and aCGH experiments followed. The samples were blinded analyzed and then unmasked to calculate specificity and sensitivity of the method. The sensitivity was 94%, the specificity 88%, while the positive prediction rate of the primary tumor was 72%. aCGH is a powerful tool in cancer diagnosis and treatment plan with high sensitivity and specificity rates. It can be performed from blood sample, which makes it an appropriate method for every patient, mainly for patients with unknown origin of the primary tumor.

Gene Expression Changes in Colorectal Cancer during Metronomic Chemotherapy and High-Concentration Drug Administration

5-fluorouracil (5-FU) and oxaliplatin, either alone or in combination, are widely used in chemotherapy for advanced colorectal cancer. Among chemotherapeutic strategies, metronomic chemotherapy has recently demonstrated promising efficacy against otherwise chemoresistant neoplasms. However, data on the efficacy of metronomic applications in cancer stem cells are lacking. This cell population is characterized by resistance to most chemotherapeutic models. In this study, we investigated the efficacy of metronomic chemotherapy and compared it with high-concentration administration of 5-FU and oxaliplatin and their combination in colon adenocarcinoma cells and colon cancer stem cells. We assessed changes in expression levels of specific genes involved in 5-FU and oxaliplatin resistance (thymidylate synthase, DNA (cytosine-5)-methyltransferase 1, dihydrofolate reductase, serine hydroxymethyltransferase, DNA excision repair protein, dihydropyrimidine dehydrogenase) in relation to drug administration schedule using quantitative real-time polymerase chain reaction. We also examined changes in cell viability. Metronomic chemotherapy showed greater efficacy in gene expression levels in colorectal cancer cells, while high, single-concentration administration was more effective in colon cancer stem cells. Regarding cell viability, no significant change was observed between metronomic and single-dose treatments. These results suggest that metronomic chemotherapy may be more effective than high-dose chemotherapy in some patients with colorectal cancer, though high, single-concentration administration may be more effective against cancer stem cells.

Detection of Circulating Tumor Cells in Patients with Breast, Prostate, Pancreatic, Colon and Melanoma Cancer: A Blinded Comparative Study Using Healthy Donors

Cancer is a diverse disease characterized by abnormal cell growth and the ability to invade or spread to other parts of the body. Because the yearly cancer rate is increasing, an important area for cancer researchers is to improve the ability to detect and treat cancer early. The current study analyzes the potential of flow cytometry to be used to detect circulating tumor cells (CTCs) in patients with various cancer types and stages. CTCs are cells that have detached from the primary tumor and entered the blood stream in the process of metastasizing to other organs. To determine the accuracy of flow cytometry in detecting CTCs, a comparative study was performed on healthy donors. In this study, blood samples from patients with breast, prostate, pancreatic, colon and skin cancer were analyzed and compared with healthy donors. The data were collected and analyzed statistically with receiver operating characteristic curve analysis. The results indicate that CTCs can be detected in over 83% of the cancer patients and therefore may be a promising method for diagnosing cancer.