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PubMed2025

Expression of Bovine Meat and Milk Factor in Hepatocellular Carcinoma and Colorectal Liver Metastasis Patients.

Bovine meat and milk factors (BMMFs) are plasmid-like DNA molecules isolated from cow's milk, meat, and human cancer tissues proposed to contribute to the development of specific types of cancer including colorectal cancer (CRC) and breast cancer based on chronic inflammation-associated indirect carcinogenesis. Chronic necro-inflammation of the liver poses a strong risk factor for the induction of hepatocellular carcinoma (HCC), which is associated with high intake of meat. Whether BMMFs contribute to HCC carcinogenesis or the development of colorectal liver metastasis (CRLM) remains unknown. Therefore, in this study, the presence of BMMFs was assessed in the liver of patients with viral and nonviral hepatitis-related HCC (n = 25), CRLM (14) and in healthy liver tissue from autopsy specimens (18) using monoclonal antibodies against the conserved BMMF Rep protein for immunohistochemistry, immunofluorescence detection, and immunoblotting. Rep was expressed in all tumor-distant and peritumor tissue specimens of HCC and CRLM patients and associated with CD68+ macrophages around portal triads. The number of Rep+CD68+cells was increased in HCC and CRLM patients compared to healthy liver tissue, which may indicate a link between BMMFs and tumor-associated chronic inflammation in the liver. Exclusively in viral hepatitis-linked HCC, Rep expression was also detected in the tumor. In addition, specifically in the liver of healthy individuals, we observed a well-defined gradient Rep expression in hepatocytes around the central veins. Altogether, these observations may indicate that the presence of BMMFs in the liver is associated with chronic inflammation and may represent a novel risk factor or surrogate marker for liver cancer.

Humans↗
PubMed2023

Bovine meat and milk factor protein expression in tumor-free mucosa of colorectal cancer patients coincides with macrophages and might interfere with patient survival.

Bovine milk and meat factors (BMMFs) are plasmid-like DNA molecules isolated from bovine milk and serum, as well as the peritumor of colorectal cancer (CRC) patients. BMMFs have been proposed as zoonotic infectious agents and drivers of indirect carcinogenesis of CRC, inducing chronic tissue inflammation, radical formation and increased levels of DNA damage. Data on expression of BMMFs in large clinical cohorts to test an association with co-markers and clinical parameters were not previously available and were therefore assessed in this study. Tissue sections with paired tumor-adjacent mucosa and tumor tissues of CRC patients [individual cohorts and tissue microarrays (TMAs) (n = 246)], low-/high-grade dysplasia (LGD/HGD) and mucosa of healthy donors were used for immunohistochemical quantification of the expression of BMMF replication protein (Rep) and CD68/CD163 (macrophages) by co-immunofluorescence microscopy and immunohistochemical scoring (TMA). Rep was expressed in the tumor-adjacent mucosa of 99% of CRC patients (TMA), was histologically associated with CD68+/CD163+ macrophages and was increased in CRC patients when compared to healthy controls. Tumor tissues showed only low stromal Rep expression. Rep was expressed in LGD and less in HGD but was strongly expressed in LGD/HGD-adjacent tissues. Albeit not reaching statistical significance, incidence curves for CRC-specific death were increased for higher Rep expression (TMA), with high tumor-adjacent Rep expression being linked to the highest incidence of death. BMMF Rep expression might represent a marker and early risk factor for CRC. The correlation between Rep and CD68 expression supports a previous hypothesis that BMMF-specific inflammatory regulations, including macrophages, are involved in the pathogenesis of CRC.

Humans↗
PubMed2004

Epidemiology of inflammation and prostate cancer.

PURPOSE: We provide an overview of some of the basic, clinical and epidemiological research that has been conducted to investigate the potential role of chronic inflammation in prostate carcinogenesis and to provide direction for future research on this hypothesis. MATERIALS AND METHODS: We reviewed the literature on this topic. RESULTS: Chronic inflammation has long been linked to cancers with an infectious etiology, such as stomach, liver and colon cancer, in patients with inflammatory bowel disease. Whether intraprostatic inflammation contributes to prostate carcinogenesis is unknown. Inflammation is frequently present in prostate biopsies, radical prostatectomy specimens and tissue resected for treatment of benign prostatic hyperplasia. Also, inflammatory infiltrates are often found in and around foci of atrophy that are characterized by an increased proliferative index. These foci, called proliferative inflammatory atrophy, may be precursors of early prostate cancer or may indicate an intraprostatic environment favorable to cancer development. Epidemiological studies have indirectly examined the role of chronic inflammation in prostate carcinogenesis through studies of pro-inflammatory and anti-inflammatory factors. When taken together studies of sexually transmitted infections, clinical prostatitis, and genetic and circulating markers of inflammation and response to infection hint at a link between chronic intraprostatic inflammation and prostate cancer. CONCLUSIONS: Additional well-designed basic, clinical and epidemiological studies are needed to resolve questions about the role of chronic inflammation in prostate carcinogenesis and to determine if intraprostatic inflammation is a rational target for chemoprevention.

Acute-Phase Proteins↗
PubMed1991

Facts and theories concerning the mechanisms of carcinogenesis.

Carcinogenesis can be induced experimentally by exposure to exogenous agents or it can occur spontaneously without intentional or active intervention. Carcinogenesis can be actively induced by chemicals, radiation, infectious biological agents, transgenesis, or selective breeding. In the human and occasionally when testing potential carcinogens in animals, cancer may result from passive exposure to carcinogens encountered in the ambient environment or from changes in the internal milieu of the animal. Many carcinogens alter the structure of DNA resulting in carcinogenesis, but a significant number of carcinogens do not appear to act through this mechanism. When the action of specific carcinogenic agents is considered in relation to the stages of cancer development, initiation, promotion, and progression, the mechanism of the induction of carcinogenesis by DNA-reactive agents that alter genomic structure can be reconciled with those agents that do not act in this manner. As some cells are fortuitously initiated by uncontrolled variables such as irradiation and through changes in normal processes, the stimulation of growth and altered genetic expression by nongenotoxic agents may result indirectly in cancer development. The final stage of carcinogenesis, progression, can occur spontaneously, enhanced by formation and propagation of genetic errors due to increased cellular proliferation associated with the promotion stage. In addition, chemical and viral agents that lack the capacity for initiation and promotion may actively convert cells in the stage of promotion to the stage of progression. Therefore, the diverse mechanisms of action of carcinogenic agents in relation to their effects on specific stages in the natural history of cancer development allow for greater congruence of many of the theories of carcinogenesis. The influence of the roles of nongenotoxic carcinogenic agents and the potential role of progressor agents on the carcinogenesis process allow a more accurate identification of the potential risk that specific carcinogenic agents pose for increasing human cancer.

Animals↗
PubMed1978

Hormonal induction of mammary tumor viruses and its implications for carcinogenesis.

The purpose of this study was to evaluate the possibility that hormones and mouse mammary tumor virus (MuMTV) are cocarcinogenic for mammary epithelium. Results of our investigations in vivo and in vitro suggest: (a) Hormones promote mammary carcinogenesis in BALB/c females whether MuMTV is germinally (BALB/c) or horizontally (BALB/cfC3H) transmitted; the rate of carcinogenesis in BALB/cfC3H females is substantially faster than it is in BALB/c, but the final mammary carcinoma incidence is approximately the same. The rate-limiting step in malignant transformation in BALB/c, which infectious MuMTV overcomes, is in premalignant transformation from normal. (b) One characteristic of horizontal MuMTV transmission in BALB/c that is not observed in germinal transmission is integration of new MuMTV sequences in mammary cell DNA. Integration is mammary cell specific and constant at 2 to 3 copies/cell from tumor to tumor. (c) MuMTV expression is changed in mammary epithelial cells during hormonal carcinogenesis. The nature of the change is qualitatively similar in both BALB/c and BALB/cfC3H. Expression of envelope glycopeptides (glycoprotein with a molecular weight of 52,000) is induced, which correlates with amplification of MuMTV RNA sequence content. Quantitative differences exist in induced levels in BALB/c and BALB/cfC3H. (d) MuMTV RNA and a glycoprotein with a molecular weight of 52,000 were not inducible with dexamethasone in normal mammary epithelial cells in culture. These structural components were induced in both premalignant (BALB/cfC3H) and malignant (BALB/c and BALB/cfC3H) cells. MuMTV RNA was induced by dexamethasone in normal cells pretreated with 5-iodo-2'-deoxyuridine. (e) Both premalignant and malignant cells have altered (vis-à-vis normal) surfaces, discernible by differences in reactivity with concanavalin A in hemadsorption assays. Indirect evidence suggests that the alteration includes membrane incorporation of MuMTV-related determinants of a glycoprotein with a molecular weight of 52,000. (f) Malignant cells exhibit enhanced sensitivity to insulin for reinitiation of DNA synthesis and mitosis in contact-inhibited homotypical monolayers. These findings have been organized into a hormonal cocarcinogenesis hypothesis in which expression of germinally transmitted MuMTV genes is the proximal cause of neoplastic transformation.

Animals↗
PubMed1965

A STUDY OF THE ANTIGENS INVOLVED IN ADENOVIRUS 12 TUMORIGENESIS BY IMMUNODIFFUSION TECHNIQUES.

The use of the agar gel diffusion technique has established the presence of three distinct antigenic reactions in the sera of Ad. 12 tumor-bearing hamsters. Only one of these antigens is directly demonstrable in the tumor. This "tumor" antigen is also formed during early stages of the infectious cycle in tissue culture cells. Other antigens present in the tumor, but only demonstrable indirectly with the use of antibody-containing serum of tumored hamsters, are the classical type-specific C antigen, and a new antigen, termed D. Of ninety-eight Ad. 12 tumored hamster sera, six reacted in gel diffusion with virus and tumor preparations, and thirty-one with tumor only. Sera which reacted in gel diffusion with viral antigen uniformly bad neutralizing antibody and high titers of CF antibody against viral and tumor antigens; however, many sera with comparable antibody titers did not react with the virus in gel diffusion. Sera which reacted in gel diffusion only with tumor antigen also had high CF antibody titers, but there was no correlation with neutralizing antibody.

Adenoviridae↗
PubMed2002

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗