Background: It is uncertain whether smoking is related to colorectal cancer risk. Cytochrome P-450 CYP1A1, glutathione-S-transferase (GST) and NAD(P)H:quinone oxidoreductase 1 (NQO1) are important enzymes in the metabolism of tobacco carcinogens, and functional genetic polymorphisms are known for these enzymes. We investigated the relation of cigarette smoking and related genetic polymorphisms to colorectal cancer risk, with special reference to the interaction between smoking and genetic polymorphism.
Methods: We used data from the Fukuoka Colorectal Cancer Study, a population-based case-control study, including 685 cases and 778 controls who gave informed consent to genetic analysis. Interview was conducted to assess lifestyle factors, and DNA was extracted from buffy coat.
Results: In comparison with lifelong nonsmokers, the odds ratios (OR) of colorectal cancer for <400, 400-799 and > or = 800 cigarette-years were 0.65 (95% confidence interval [CI], 0.45-0.89), 1.16 (0.83-1.62) and 1.14 (0.73-1.77), respectively. A decreased risk associated with light smoking was observed only for colon cancer, and rectal cancer showed an increased risk among those with > or = 400 cigarette-years (OR 1.60, 95% CI 1.04-2.45). None of the polymorphisms under study was singly associated with colorectal cancer risk. Of the gene-gene interactions studied, the composite genotype of CYP1A1*2A or CYP1A1*2C and GSTT1 polymorphisms was associated with a decreased risk of colorectal cancer, showing a nearly statistically significant (Pinteraction = 0.06) or significant interaction (Pinteraction = 0.02). The composite genotypes of these two polymorphisms, however, showed no measurable interaction with cigarette smoking in relation to colorectal cancer risk.
Conclusions: Cigarette smoking may be associated with increased risk of rectal cancer, but not of colon cancer. The observed interactions between CYP1A1 and GSTT1 polymorphisms warrant further confirmation.
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http://dx.doi.org/10.1186/1471-2407-10-274 | DOI Listing |
Neoplasma
December 2024
Department of Gastrointestinal Surgery, Renmin Hospital of Wuhan University, Wuchang, Wuhan, Hubei, China.
Many lines of evidence suggest that circular RNAs (circRNAs) are closely associated with the occurrence and progression of colon cancer. The objective of this study was to investigate the regulatory effects and mechanisms of circ_0075829 on ferroptosis and immune escape in colon cancer. We utilized colon cancer cell lines and a xenograft mouse model to analyze the function of circ_0075829 in vitro and in vivo.
View Article and Find Full Text PDFRegarding flotillin knockdown, drug resistance is reversed in colorectal cancer (CRC) cell lines; this is associated with the phosphoinositide 3-kinase/protein kinase B (PI3K/AKT) pathway, as our previous experimental results indicated. However, the exact mechanism underlying this pathway remains unclear. PI3K inhibitor and activator were added separately to clarify the role of the PI3K pathway in reversing drug resistance.
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January 2025
Department of Colorectal Surgery, Peace Hospital Affiliated to Changzhi Medical College, 110 Yan'an South Road, Luzhou District, Changzhi City, 046000, Shanxi Province, China.
Objective: To investigate the efficacy of laparoscopic sigmoid extraperitoneal colostomy combined with pelvic peritoneal closure in abdominoperineal resection for low rectal cancer.
Methods: We retrospectively analyzed the clinical data of 162 patients with low rectal cancer, who underwent laparoscopic abdominoperineal resection from January 2015 to January 2019 at the Affiliated Peace Hospital of Changzhi Medical College. Extraperitoneal stoma construction was performed in 98 patients (study group), while 64 patients (control group) underwent the procedure without suturing the pelvic peritoneum.
Discov Oncol
January 2025
Department of Gastrointestinal Surgery, The Second Affiliated Hospital of Zunyi Medical University, Zunyi, 563006, Guizhou, People's Republic of China.
Nonylphenol (NP) is a common environmental contaminant and endocrine disruptor. Our previous research demonstrated that NP could promote the proliferation and epithelial-mesenchymal transition (EMT) of colorectal cancer (CRC) cells; however, the specific mechanism remains unclear. miRNA sequencing revealed that NP upregulated the expression levels of microRNA(miR)-151a-3p in CRC.
View Article and Find Full Text PDFDiscov Oncol
January 2025
Department of General Surgery, Tianjin Fifth Central Hospital, No. 41 Zhejiang Road, Binhai New Area, Tianjin, 300450, China.
Gastric cancer (GC), a prevalent malignancy worldwide, encompasses a multitude of biological processes in its progression. Recently, ferroptosis, a novel mode of cell demise, has become a focal point in cancer research. The microenvironment of gastric cancer is composed of diverse cell populations, yet the specific gene expression profiles and their association with ferroptosis are not well understood.
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