Exploring the role of the gut microbiome in oncology is gaining more attention, mainly due to its ability to shape the immune system in cancer patients. A well-balanced microbial composition forms a symbiotic relationship with the host organism. Mounting evidence supports the potential of modifiable lifestyle factors, such as diet and physical activity, in restoring intestinal dysbiosis related to cancer development and treatment.
View Article and Find Full Text PDFDNA methylation represents a crucial mechanism of epigenetic regulation in hematologic malignancies. The methylation process is controlled by specific DNA methyl transferases and other regulators, which are often affected by genetic alterations. Global hypomethylation and hypermethylation of tumor suppressor genes are associated with hematologic cancer development and progression.
View Article and Find Full Text PDFThe tumor microenvironment (TME) plays a significant role in tumor progression and cancer cell survival. Besides malignant cells and non-malignant components, including immune cells, elements of the extracellular matrix, stromal cells, and endothelial cells, the tumor microbiome is considered to be an integral part of the TME. Mounting evidence from preclinical and clinical studies evaluated the presence of tumor type-specific intratumoral bacteria.
View Article and Find Full Text PDFUnderstanding the mechanisms of resistance to therapy in human cancer cells has become a multifaceted limiting factor to achieving optimal cures in cancer patients. Besides genetic and epigenetic alterations, enhanced DNA damage repair activity, deregulation of cell death, overexpression of transmembrane transporters, and complex interactions within the tumor microenvironment, other mechanisms of cancer treatment resistance have been recently proposed. In this review, we will summarize the preclinical and clinical studies highlighting the critical role of the microbiome in the efficacy of cancer treatment, concerning mainly chemotherapy and immunotherapy with immune checkpoint inhibitors.
View Article and Find Full Text PDFPancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive malignant tumors due to the absence of biomarkers for early-stage detection and poor response to therapy. Since mounting evidence supports the role of microbiota composition in tumorigenesis and cancer treatment, the link between microbiome and PDAC has been described. In this review, we summarize the current knowledge regarding the impact of the gut and oral microbiome on the risk of PDAC development.
View Article and Find Full Text PDFPancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive solid malignancies due to the rapid rate of metastasis and high resistance to currently applied cancer therapies. The complex mechanism underlying the development and progression of PDAC includes interactions between genomic, epigenomic, and signaling pathway alterations. In this review, we summarize the current research findings on the deregulation of epigenetic mechanisms in PDAC and the influence of the epigenome on the dynamics of the gene expression changes underlying epithelial-mesenchymal transition (EMT), which is responsible for the invasive phenotype of cancer cells and, therefore, their metastatic potential.
View Article and Find Full Text PDFThe development of distant metastases is the final stage in the progression of solid cancer and is responsible for the majority of cancer-related deaths. Epithelial-mesenchymal transition (EMT) is involved in cancer progression and metastasis. In the present study we used different types of intracellular bacteria isolated from colorectal cancer biopsies to examine their effect on the expression of SNAI1 and VIM genes in Caco2 cell line.
View Article and Find Full Text PDFThe development of colorectal cancer is affected by many factors, especially the intestinal microbiota. However, precise knowledge of bacterial communities associated with the mucosa in various parts of the colon is limited. Herein, we applied the gentamicin protection assay and detected the presence of intracellular bacteria in colorectal biopsies from Slovak patients with colorectal adenoma and carcinoma, and we compared this with healthy controls.
View Article and Find Full Text PDFColorectal cancer is the 4th most common cause of cancer related deaths worldwide and new possibilities in accurate diagnosis and targeted treatment are highly required. Mutations in adenomatous polyposis coli (APC) gene play a pivotal role in adenoma-carcinoma pathway of colorectal tumorigenesis. The quarter century from its´ first cloning, APC became one of the most frequently mutated, known driver genes in colorectal cancer.
View Article and Find Full Text PDFObjectives: Bacteria from the intestinal tract of Slovak and American HIV/AIDS patients and Slovak colon cancer patients were tested for the capacity to be internalized by cells of the HL-60 cell line as well as by normal human lymphocytes. They were anticipated to possess a specific characteristic, i.e.
View Article and Find Full Text PDFPurpose: Availability without prescription restriction, low cost, and simple oral administration allow cancer patients to use probiotics without knowledge of potential risks. We present a survey of probiotic use and the association with patient tumor characteristics in cancer patients treated at the outpatient department of the National Cancer Institute in Slovakia.
Patients And Methods: Between March and December 2014, 499 patients were asked to evaluate their overall experience with probiotics by questionnaire form, including the length and method of use relative to anticancer therapy, expectations, side-effect experiences, understanding of the possible risks, dietary supplement use, and others.
Increasing incidence and mortality of colorectal cancer brings the necessity to uncover new possibilities in the prevention, diagnosis and treatment. The microbiome as the collective genetic material of the microflora, overexceed the number of genes in the human genome and is unique for each individual. Due to the benefits providing for the host and mainly for immediate interaction with the host immune system, a gastrointestinal microflora can be considered "cardinal microbiome".
View Article and Find Full Text PDFObjectives: Human immunodeficiency virus type 1 is widely accepted as the cause of AIDS (Acquires Immunodeficiency Syndrome) but it is necessary to consider other factors, not only HIV, which may be involved in AIDS process. It is apparent that a viral reservoir persists in virtually all infected individuals receiving HAART. Reservoirs were detected in macrophages and other cells of the blood system, in which even very effective HAART was not able to eliminate the virus.
View Article and Find Full Text PDFColorectal cancer mortality is one of the most common cause of cancer-related mortality. A multiple risk factors are associated with colorectal cancer, including hereditary, enviromental and inflammatory syndromes affecting the gastrointestinal tract. Familial adenomatous polyposis (FAP) is characterized by the emergence of hundreds to thousands of colorectal adenomatous polyps and FAP syndrome is caused by mutations within the adenomatous polyposis coli (APC) tumor suppressor gene.
View Article and Find Full Text PDFBackground: Familial adenomatous polyposis (FAP) is a hereditary disease induced by germ-line mutations in the tumor suppressor APC gene. These initiate the early stages of the adenoma-carcinoma sequence in familial, but also in sporadic (in 80% to 90%), colon tumorigenesis. We found the presence of APC-like sequences in bacteria of FAP patients.
View Article and Find Full Text PDFObjectives: Familial adenomatous polyposis (FAP) is an autosomal dominant disease characterized by the presence of hundreds to thousands of benign polyps in the colon. If not removed prophylactically they represent a risk of developing malignant cancer with an almost 100% penentrance. FAP is induced by germline mutation in the APC gene.
View Article and Find Full Text PDFBackground: Bacteria and yeasts isolated from respiratory tracts of 39 Cambodian and 28 Kenyan HIV-positive children were tested for the presence of HIV-1 sequences.
Material/methods: Bacteria and yeasts from the respiratory tract (nose, pharyngeal swabs) were isolated from 39 Cambodian and 28 Kenyan HIV-positive children. Bacterial chromosomal DNA was prepared by standard protocol and by Qiagen kit.
Objectives: Polymorphism in the adenomatous polyposis coli (APC) gene was analyzed in 33 families suspected of familial adenomatous polyposis (FAP) without identified APC gene mutation. Screening of 104 members of mentioned families for polymorphism in the APC gene, was performed using single strand conformation polymorphism (SSCP) and DNA sequencing.
Results: Twelve different types of polymorphism were found in the cohort of the families analyzed.
Germline mutation in APC gene induced development of familial adenomatous polyposis (FAP). The risk of developing specific manifestation of FAP is often correlated with the position of the inherited APC mutation. Patients with mutations localized in the largest exon 15 between codons 1286 and 1513 (mutation cluster region, MCR) have generally a worse prognosis with early onset of the disease.
View Article and Find Full Text PDFNeuro Endocrinol Lett
October 2008
Objectives: The adenomatous polyposis coli (APC) gene was analyzed for germline mutations in 113 familial adenomatous polyposis suspected families from all over Slovakia. Mutation screening was performed using single strand conformation polymorphism (SSCP) and DNA sequencing.
Results: Mutations in the APC gene were found in 39 (34.
Neuro Endocrinol Lett
October 2007
Objectives: Bacterial DNA isolated from the intestinal tract of 11 American and 30 Slovak HIV/AIDS patients were analyzed by colony and dot blot hybridization assay for HIV-1 specific sequences. Secondly, PCR using primers specific for the HIV-1 gag, pol and env genes for detection of HIV-1 sequences in these DNA were performed.
Results: Intestinal bacteria DNA of HIV/AIDS patients hybridized in colony and dot blot hybridization assay for HIV-1 specific sequences.
Neuro Endocrinol Lett
December 2006
Objectives: Bacteria purified from the intestinal tract of HIV/AIDS patients were tested for the capacity to be internalised by cells of the HL-60 cell line. Secondly, the bacteria have been applied to the rabbit's colon in order to test their pathogenic ability.
Results: The ability of the bacteria to be internalised by HL-60 cells was found to be very expressive.
Germline mutations in BRCA1 and BRCA2 have been predominantly associated with the breast and ovarian cancers. Two mutations in BRCA1 (185delAG and 5382insC) and one mutation in BRCA2 (6174delT) are common in Ashkenazi Jewish population. To determine the proportion of these founder mutations, we analyzed DNA samples of 120 Slovak hereditary breast and/or ovarian cancer (HBOC) suspected families.
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