Epidemiological and molecular evaluation of BRAF, KRAS, NRAS genes and MSI in the development of colorectal cancer.

Background And Objectives: KRAS, NRAS, BRAF mutations and microsatellite instability (MSI) can be associated with Colorectal Cancer (CRC) development.

Material And Methods: We evaluated 828 medical records of CRC patients from a school hospital from January/2016 to December/2020. Variables such as age, gender, ethnicity, literacy level, smoking, alcoholism, primary anatomical site, tumor staging, presence of BRAFV600E, KRAS, NRAS mutations and MSI , survival and metastasis were identified.

Treatment effects of the EGFR pathway drugs on head and neck cancer stem cells.

(1) Head and neck cancer (HNC) is the sixth most common cancer worldwide and show low survival rates and drug resistance, which can be due to the presence of cancer stem cells (CSCs), a small cell population with metastatic potential, invasion and self-renewal ability. (2) Here, seven tumor cells were sorted as CD44+/CD117+/CD133+ or ALDH+, considered as HNC stem cells (HNCSCs), and as CD44-/CD117-/CD133- or ALDH-, considered non-HNCSCs after both cells sorted criteria was compared to evaluate cell migration, invasion, and colony forming assays. These subpopulations were treated with Cetuximab, Paclitaxel, or a combination of both drugs and evaluated for cell viability.

Association between folate metabolism polymorphisms and breast cancer: a case-control study.

We investigated the association between methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthetase (MTR A2756G), and methionine synthase reductase (MTRR A66G) polymorphisms involved in folate pathway and breast cancer risk, and the interaction between these polymorphisms and tobacco and alcohol consumption. Furthermore, we evaluated the association between these polymorphisms and clinicopathological variables. This case-control study included 606 Brazilian women, comprising 128 patients with breast cancer and 478 controls.

Evaluation of molecular markers GSTM1 and GSTT1 and clinical factors in breast cancer: case-control study and literature review.

The study was conducted to evaluate the frequency of polymorphisms in and genes in patients with breast cancer compared with individuals without history of cancer, and the association of these polymorphisms with clinical/epidemiological parameters.There were evaluated 752 women (219 patients and 533 controls). Molecular analysis was performed by the Polymerase Chain Reaction (PCR).

Anti-EGFR treatment effects on laryngeal cancer stem cells.

Laryngeal cancer (LC) is one of the common head and neck neoplasms and is characterized by resistance to conventional therapy and poor prognosis. This may result from the presence of cancer stem cells (CSCs), which form a small population in tumors with metastatic potential, high invasive capacity, self-renewal, and differentiation. This study aimed to evaluate the effectiveness of 5-fluorouracil and cisplatin individually, as well as the combination of cetuximab and paclitaxel in a CSC subpopulation separated with biomarkers related to tumoral growth (CD44, CD117, and CD133).

Gene Polymorphisms Involved in Folate Metabolism and DNA Methylation with the Risk of Head and Neck Cancer.

Background: Folate is essential for DNA synthesis, repair, and methylation. Polymorphisms in genes associated with folate metabolism may alter these processes and, consequently, modulate cancer development.

Aim: We aimed to assess DNMT3B -149C/T (rs2424913), DNMT3B -283T/C (rs6087990), DNMT3B -579G/T (rs2424909), DHFR 19-pb ins/del (rs70991108), SHMT1 1420C/T (rs1979277), and TYMS 28-bp tandem repeat (rs34743033) polymorphisms with risk of head and neck cancer.

Polymorphisms in , , and genes involved in folate metabolism and thyroid cancer: a case-control study.

Introduction: Polymorphisms in genes coding enzymes involved in folate metabolism may cause alterations in this metabolic pathway and contribute to carcinogenesis, because folate is essential for DNA synthesis, methylation and repair. The objective of this study was to investigate the association of 677C>T (rs1801133), 2756A>G (rs1805087), 80A>G (rs1051266) and 844ins(68) (no rs#) polymorphisms and thyroid cancer development. The association of these polymorphisms with demographic risk factors and clinical histopathological parameters was also evaluated.

Relationship between CD44/CD133/CD117 cancer stem cells phenotype and Cetuximab and Paclitaxel treatment response in head and neck cancer cell lines.

Recent evidence suggests that cancer stem cells (CSCs), a small population of cancer cells that are highly tumourigenic, capable of self-renewal and have the ability to differentiate into cells that constitute the tumor, are the "drivers" of local recurrence and metastatic spread and may be associated with resistant to conventional therapy. The objectives of the study are to identify and characterize two head and neck cancer cell lines with regard CD44/CD133/CD117 profile (CSCs) and CD44/CD133/CD117 profile (Non-CSCs); to investigate the influence of chemotherapy treatment in CSCs and compare with Non-CSCs; to evaluate CD44 and EGFR gene expression in CSCs. Fluorescent-activated cell sorting (FACS) using specific cell surface marker combination (CD44, CD117 and CD133) was performed to isolate CSCs of Non-CSCs from cell lines.

Polymorphisms of folate metabolism genes in patients with cirrhosis and hepatocellular carcinoma.

Aim: To evaluated the association of the risk factors and polymorphisms in , , and genes.

Methods: Patients with cirrhosis ( = 116), hepatocellular carcinoma (HCC) ( = 71) and controls ( = 356) were included. Polymerase chain reaction followed by enzymatic digestion and allelic discrimination technique real-time PCR techniques were used for analysis.