Reinterpretation of the Wartburg effect leads to understanding aerobic glycolysis as a process that provides considerable amount of molecular precursors for the production of lipids, nucleotides and amino acids that are necessary for continuous growth and rapid proliferation characteristic for cancer cells. Human papilloma virus (HPV) is a number one cause of cervical carcinoma with 99% of the cervical cancer patients being HPV positive. This tight link between HPV and cancer raises the question if and how HPV impact cells to reprogram their metabolism? Focusing on early phase proteins E1, E2, E5, E6 and E7 we demonstrate that HPV activates plethora of metabolic pathways and directly influences enzymes of the glycolysis pathway to promote the Warburg effect by increasing glucose uptake, activating glycolysis and pentose phosphate pathway, increasing the level of lactate dehydrogenase A synthesis and inhibiting β-oxidation. Our considerations lead to conclusion that HPV is substantially involved in metabolic cell reprogramming toward neoplastic phenotype and its metabolic activity is the fundamental reason of its oncogenicity.
Using Raman microscopy, we investigated epithelial cervical cells collected from 96 women with squamous cell carcinoma (SCC) or belonging to groups I, IIa, IIID-1 and IIID-2 according to Munich III classification (IIID-1 and IIID-2 corresponding to Bethesda LSIL and HSIL groups, respectively). All women were tested for human papillomavirus (HPV) infection using PCR. Subcellular resolution of Raman microscopy enabled to understand phenotypic differences in a heterogeneous population of cervical cells in the following groups: I/HPV−, IIa/HPV−, IIa/HPV−, LSIL/HPV−, LSIL/HPV+, HSIL/HPV−, HSIL/HPV+ and cancer cells (SCC/HPV+). We showed for the first time that the glycogen content in the cytoplasm decreased with the nucleus size of cervical cells in all studied groups apart from the cancer group. For the subpopulation of large-nucleus cells HPV infection resulted in considerable glycogen depletion compared to HPV negative cells in IIa, LSIL (for both statistical significance, ca. 45%) and HSIL (trend, 37%) groups. We hypothesize that accelerated glycogenolysis in large-nucleus cells may be associated with the increased protein metabolism for HPV positive cells. Our work underlines unique capabilities of Raman microscopy in single cell studies and demonstrate potential of Raman-based methods in HPV diagnostics.
17 October 2017 in Journal of Cancer Research and Clinical Oncology
Purpose To evaluate the impact of HPV16 load (VL—the number of virus genome copies per cell) and P16 expression on prognosis of patients with squamous cell carcinomas (SCCs) of head and neck (HN). Materials and methods HPV16 presence was assessed in the group of 109 patients with HNSCCs by quantitative polymerase chain reaction (qPCR). VL (assessed by qPCR) and P16 expression (evaluated by immunohistochemistry) were analysed only in the subgroup of HPV16-positive tumours. These features were correlated with 5-year overall survival (OS) and disease-free survival (DFS). Results HPV16 infection was found in 36 tumours (33.0%). Virus-positive patients had better OS and DFS than those without infection (P = 0.041 and 0.005). Among HPV16-positive HNSCCs, 18 (50.0%) had higher VL (median value > 6764.3 copies/cell) and 25 (73.5%) P16 over expression. The significant differences in OS and DFS (P = 0.008 and 0.004) were noticed according to VL, wherein 100% DFS was found for patients with higher VL. According to P16 expression, significant difference was found only for OS (P = 0.020). In multivariate analysis, VL (P = 0.045; HR = 2.795; CI 0.121–1.060) and the level of smoking (P = 0.023, HR = 2.253; CI 1.124–4.514) were independent factors affecting DFS of HPV16-positive patients. Conclusion On the basis of viral load, it is possible to differentiate prognosis of patients with HPV16-positive HNSCCs. In this subgroup, viral load has stronger prognostic potential than P16 expression.
Cellular lipid metabolism is significantly transformed during oncogenesis. To assess how dysplasia development influences lipid cellular metabolisms and what is the molecular background behind it, cervical epithelial cells of 63 patients assigned to seven groups (based on the cytological examination and HPVhr test results) were studied using a multimethodological approach including Raman microscopy and molecular methods. The consistent picture obtained studying the lipid content, cell inflammation, SREBF1 gene methylation (hence SREBP1 inhibition) and level of mitochondrial DNA copies (indirectly the number of mitochondria) showed that changes in lipid metabolism were multidirectional. Cells from patients classified as mildly dysplastic (LSIL) exhibited a unique behavior (the highest level of inflammation and SREBF1 methylation, the lowest lipid content and mitochondrial DNA). On the contrary, cells from severe dysplastic (HSIL) and cancer (SCC) groups showed the opposite characteristics including the lowest SREBF1 gene methylation as well as the highest level of mitochondrial DNA and lipid cellular concentration (for HSIL/HPVhr+ and SCC groups). Following dysplastic progression, the lipid content decreases significantly (compared to the control) for mildly abnormal cells, but then increases for HSIL/HPVhr+ and SCC groups. This intriguing dual switch in lipid metabolism (reflected also in other studied parameters) on the way from normal to squamous carcinoma cells is of potential diagnostic interest.
The natural history of cytomegalovirus (CMV) infection and disease in transplant recipients prompts researchers to look for other factors contributing to this infection. The ubiquity of lymphotropic herpesviruses (EBV, HHV-6, and HHV-7) and the possibility of their activation during immunosuppression may suggest their participation in progression of CMV infection in patients after hematopoietic stem cell transplantation (HSCT). The presence of CMV, EBV, HHV-6 and HHV-7 was confirmed through detection of viral DNA isolated from leukocytes. Allo-HSCT recipients (n=55) were examined repeatedly within the average period of 14±7.3 months post-transplant. CMV DNA was detected in 24% of samples, while EBV, HHV-6 and HHV-7 were detected in 20%, 15% and 14% of samples, respectively. Based on the presence of CMV infection at particular time-points (months) after transplantation, the recipients were divided into 3 groups: Group I (N=15) with persistent infection, Group II (N=20) with transient infection, and Group III (N=20) without CMV infection. In Group I, the mean CMV load was significantly higher than in Group II, and the clinical condition of Group I patients was poorer. All these patients manifested clinical symptoms, and all had episodes of GvHD. All Group I patients developed multiple infections; EBV in 80%, HHV-6 in 47% and HHV-7 in 87% of patients. In the remaining groups, with the exception of HHV-6 in group II, the frequency of infected patients was lower. In addition, CMV presence was often preceded by another herpesvirus. The results suggest that other herpesviruses, mainly HHV-7, could predispose CMV to cause chronic infection.
In the world, there are many tests that allow the detection of HPV infection. These tests are based on different operating principles and have different levels of sensitivity. The first test to detect HPV infection was approved by the Food and Drug Administration in 2003. Since then, the FDA has approved five more commercial tests for this purpose, the last one in 2018. This paper discusses the principles of molecular tests to detect HPV, which have been approved by the FDA, the main differences between them, as well as their advantages and disadvantages. In the world, there are many tests that allow the detection of HPV infection. These tests are based on different operating principles and have different levels of sensitivity. The first test to detect HPV infection was approved by the Food and Drug Administration in 2003. Since then, the FDA has approved five more commercial tests for this purpose, the last one in 2018. This paper discusses the principles of molecular tests to detect HPV, which have been approved by the FDA, the main differences between them, as well as their advantages and disadvantages.