Hepatocellular carcinoma (HCC) imposes a significant burden on global public health. Exposure to aflatoxins, potent mycotoxins produced by Aspergillus fungi contaminating staple foods, and chronic hepatitis B virus (HBV) infection are major etiological factors, especially where they co-exist. This review examines the critical role of the p53 tumor suppressor pathway as a primary target and convergence point for the carcinogenic actions of aflatoxins and HBV. Aflatoxin B₁ (AFB₁), a Group 1 carcinogen, exerts significant genotoxicity, characteristically inducing a specific hotspot mutation (R249S) in the TP53 gene via DNA adduct formation, thereby compromising p53’s critical tumor suppressor functions. This R249S mutation is considered a molecular fingerprint of aflatoxin exposure. Concurrently, the HBV X protein (HBx) functionally inactivates wild-type p53 through direct binding and by promoting its degradation. The synergistic disruption of the p53 pathway, driven by AFB₁-induced mutation and amplified by HBV-mediated functional inhibition, significantly enhances the risk of HCC development. This review addresses how aflatoxin exposure alters key aspects of p53 and how this damage interacts with HBV-mediated p53 suppression, providing crucial insights into hepatocarcinogenesis. The knowledge synthesized here underscores the importance of mitigating aflatoxin exposure alongside HBV control for effective HCC prevention and treatment strategies.

Background: Epstein–Barr virus (EBV) is involved in the development of lymphomas, nasopharyngeal carcinomas (NPC), and a subgroup of gastric carcinomas (GC), and has also been detected in lung carcinomas, even though the role of the virus in this malignancy has not yet been established. BamH1-A Rightward Frame 1 (BARF1), a suggested exclusive epithelial EBV oncoprotein, is detected in both EBV-associated GCs (EBVaGC) and NPC. The expression and role of BARF1 in lung cancer is unknown. Methods: A total of 158 lung carcinomas including 80 adenocarcinomas (AdCs) and 78 squamous cell carcinomas (SQCs) from Chilean patients were analyzed for EBV presence via polymerase chain reaction (PCR), Immunohistochemistry (IHC), or chromogenic in situ hybridization (CISH). The expression of BARF1 was evaluated using Reverse Transcription Real-Time PCR (RT-qPCR). Additionally, A549 and BEAS-2B lung epithelial cells were transfected with a construct for ectopic BARF1 expression. Cell proliferation, migration, invasion, and epithelial–mesenchymal transition (EMT) were evaluated. Results: We found that EBV was present in 37 out of 158 (23%) lung carcinomas using PCR. Considering EBV-positive specimens using PCR, IHC for Epstein–Barr nuclear antigen 1 (EBNA1) detected EBV in 24 out of 30 (80%) cases, while EBERs were detected using CISH in 13 out of 16 (81%) cases. Overall, 13 out of 158 (8%) lung carcinomas were shown to be EBV-positive using PCR/IHC/CISH. BARF1 transcripts were detected in 6 out of 13 (46%) EBV-positive lung carcinomas using RT qPCR. Finally, lung cells ectopically expressing BARF1 showed increased migration, invasion, and EMT. Conclusions. EBV is frequently found in lung carcinomas from Chile with the expression of BARF1 in a significant subset of cases, suggesting that this viral protein may be involved in EBV-associated lung cancer progression.

Xenobiotics are non-natural chemical compounds to which the human population is exposed. Chronic exposure to certain xenobiotics is associated with various diseases, including cancer development. Anelloviruses (AVs), including Torque Teno Virus (TTV), Torque Teno Mini Virus (TTMV), and Torque Teno Midi Virus (TTMDV), are ubiquitous viruses found in the general population. As no disease has been definitively associated with AVs, they are sometimes referred to as “viruses awaiting a disease”. This review explores the potential roles of xenobiotics and AVs in colorectal cancer (CRC) development and suggests a potential interplay between them. Evidence suggests an association between certain xenobiotics (like pesticides, cigarette smoke components, and dietary factors) and CRC, while such an association is less clear for AVs. The high prevalence of AVs suggests these infections alone may be insufficient to disrupt homeostasis; thus, additional factors might be required to promote disease, potentially including cancer.

Hepatocellular carcinoma (HCC) is a significant burden on global public health, being one of the main causes of cancer mortality worldwide. This type of cancer has been closely linked to viral and environmental factors, particularly hepatitis B virus (HBV) infection and exposure to aflatoxins, produced by fungi of the genus Aspergillus. Aflatoxins are known carcinogens found in contaminated foods, such as grains and nuts. In the presence of chronic HBV infection, they can function as cofactors in liver carcinogenesis. The synergistic interaction between HBV and aflatoxins is crucial for understanding the molecular complexity of HCC. Multiple studies have shown how the simultaneous presence of these carcinogens significantly increases the risk of developing HCC. The complexity of these mechanisms highlights the urgent need for targeted preventive and therapeutic strategies, ranging from improvements in food safety and aflatoxin regulation to widespread HBV vaccination in high-prevalence areas. Understanding the molecular interactions between these environmental and viral factors is crucial not only for the diagnosis and treatment of HCC, but also for the effective implementation of public health policies that re-duce the global burden of this devastating liver disease. A multifactorial approach is essential to effectively address the increasing prevalence of HCC worldwide and improve health outcomes for affected populations.

Torque teno virus (TTV) is a highly prevalent DNA virus in humans, but its role in carcinogenesis is not well understood. While human papillomavirus (HPV) is a well-established etiological agent in cervical cancer, co-infections with other viruses such as Epstein–Barr virus (EBV) or TTV may influence disease progression. We conducted a cross-sectional study using 94 formalin-fixed, paraffin-embedded (FFPE) cervical tissue samples. These specimens were collected from women with cervical intraepithelial lesions (CINI-III) or squamous cell carcinoma (SCC) at the Clinical Hospital of the University of Chile. After extracting DNA, we screened for TTV using real-time polymerase chain reaction (qPCR). Statistical analysis was performed using Fisher’s exact test. Of the 94 samples, 83 were positive for the human β-globin gene and included in the final analysis. TTV was detected in 12.0% (10/83) of these samples. Among the TTV-positive cases, the virus was most frequently detected in high-grade lesions (70.0%), followed by low-grade lesions (20.0%) and squamous cell carcinoma (10.0%). However, these differences were not statistically significant (p = 0.688). This is the first study to assess TTV prevalence in cervical lesions among Chilean women. Although we found no statistically significant associations, a higher frequency of TTV was detected in precursor lesions compared to SCC. Further studies are needed to understand the potential immunomodulatory role of TTV in cervical carcinogenesis.