scholarly journals Inhibition of Polo-like kinase 1 (PLK1) to facilitate the reactivation and elimination of latent gamma-herpesviruses

2020 ◽  
Author(s):  
Ayan Biswas ◽  
Guillaume Fiches ◽  
Dawei Zhou ◽  
Jianwen Que ◽  
Jian Zhu ◽  
...  

AbstractBoth Kaposi’s sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) can establish the persistent, life-long infection primarily at the latent status, and contribute to certain types of tumors, including B cell lymphomas, especially in immuno-compromised individuals, such as people living with HIV (PLWH). Lytic reactivation of these viruses can be employed to kill tumor cells harboring latently infected viral episomes, through the viral cytopathic effects and the subsequent antiviral immune responses. In this study, we identified that expression of Polo-like kinase 1 (PLK1) in B cells is elevated in the context of HIV infection and by HIV Nef protein. We further demonstrated that PLK1 depletion or inhibition can promote KSHV reactivation and cell death of KSHV-reactivated tumor cells. Mechanistically, PLK1 regulates Myc protein that is critical for both maintenance of KSHV latency and support of cell survival, and affects the level of H3K27me3 suppressive mark both globally and at certain loci of KSHV viral episomes. Lastly, we recognized that PLK1 inhibition can synergize with STAT3 inhibition to induce efficient KSHV reactivation. PLK1 depletion or inhibition yielded the similar effect on promoting EBV reactivation and cell death of EBV-reactivated tumor cells. Our findings illustrated that PLK1 is a novel host target that can be inhibited to benefit the viral oncolysis to eliminate KSHV/EBV-infected tumor cells.

2021 ◽  
Vol 17 (7) ◽  
pp. e1009764
Author(s):  
Ayan Biswas ◽  
Dawei Zhou ◽  
Guillaume N. Fiches ◽  
Zhenyu Wu ◽  
Xuefeng Liu ◽  
...  

Both Kaposi’s sarcoma-associated herpesvirus (KSHV) and Epstein-Barr virus (EBV) establish the persistent, life-long infection primarily at the latent status, and associate with certain types of tumors, such as B cell lymphomas, especially in immuno-compromised individuals including people living with HIV (PLWH). Lytic reactivation of these viruses can be employed to kill tumor cells harboring latently infected viral episomes through the viral cytopathic effects and the subsequent antiviral immune responses. In this study, we identified that polo-like kinase 1 (PLK1) is induced by KSHV de novo infection as well as lytic switch from KSHV latency. We further demonstrated that PLK1 depletion or inhibition facilitates KSHV reactivation and promotes cell death of KSHV-infected lymphoma cells. Mechanistically, PLK1 regulates Myc that is critical to both maintenance of KSHV latency and support of cell survival, and preferentially affects the level of H3K27me3 inactive mark both globally and at certain loci of KSHV viral episomes. Furthremore, we recognized that PLK1 inhibition synergizes with STAT3 inhibition to efficiently induce KSHV reactivation. We also confirmed that PLK1 depletion or inhibition yields the similar effect on EBV lytic reactivation and cell death of EBV-infected lymphoma cells. Lastly, we noticed that PLK1 in B cells is elevated in the context of HIV infection and caused by HIV Nef protein to favor KSHV/EBV latency.


Cancers ◽  
2021 ◽  
Vol 13 (17) ◽  
pp. 4366
Author(s):  
Jose-Tomas Navarro ◽  
José Moltó ◽  
Gustavo Tapia ◽  
Josep-Maria Ribera

Despite widespread use of combined antiretroviral therapy (cART) and increased life expectancy in people living with HIV (PLWH), HIV-related lymphomas (HRL) remain a leading cause of cancer morbidity and mortality for PLWH, even in patients optimally treated with cART. While the incidence of aggressive forms of non-Hodgkin lymphoma decreased after the advent of cART, incidence of Hodgkin lymphoma (HL) has increased among PLWH in recent decades. The coinfection of Epstein–Barr virus plays a crucial role in the pathogenesis of HL in the HIV setting. Currently, PLWH with HRL, including HL, are treated similarly to HIV-negative patients and, importantly, the prognosis of HL in PLWH is approaching that of the general population. In this regard, effective cART during chemotherapy is strongly recommended since it has been shown to improve survival rates in all lymphoma subtypes, including HL. As a consequence, interdisciplinary collaboration between HIV specialists and hemato-oncologists for the management of potential drug–drug interactions and overlapping toxicities between antiretroviral and antineoplastic drugs is crucial for the optimal treatment of PLWH with HL. In this article the authors review and update the epidemiological, clinical and biological aspects of HL presenting in PLWH with special emphasis on advances in prognosis and the factors that have contributed to it.


Author(s):  
Jose Tomas Navarro ◽  
Jose Moltó ◽  
Gustavo Tapia ◽  
Josep Maria Ribera

Despite widespread use of combined antiretroviral therapy (cART) and increased life expectancy in people living with HIV (PLWH), HIV-related lymphomas (HRL) remain a leading cause of cancer morbidity and mortality for PLWH, even in patients optimally treated with cART. While incidence of aggressive forms of non-Hodgkin lymphoma decreased after cART advent, incidence of Hodgkin lymphoma (HL) has increased among PLWH in recent decades. The coinfection of Epstein Barr virus plays a crucial role in the pathogenesis of HL in the HIV setting. Currently, PLWH with HRL, including HL, are treated similarly to HIV-negative patients and, importantly, the prognosis of HL in PLWH is approaching to that of the general population. In this regard, effective chem-otherapy is strongly recommended since it has been shown to improve survival rates in all lymphoma subtypes, including HL. As a consequence, interdisciplinary collaboration between HIV specialists and hemato-oncologists for the management of potential drug-drug interactions and overlapping toxicities between antiretroviral and antineoplastic drugs is crucial for the op-timal treatment of PLWH with HL. In this article the authors review and update the epidemio-logical, clinical and biological aspects of HL presenting in PLWH with special emphasis in the improvement on prognosis and the factors that have contributed to it.


2021 ◽  
Vol 12 (1) ◽  
pp. 150-156
Author(s):  
Soehartati A. Gondhowiardjo ◽  
Handoko ◽  
Marlinda Adham ◽  
Lisnawati Rachmadi ◽  
Henry Kodrat ◽  
...  

Background: Nasopharyngeal cancer is commonly associated with Epstein–Barr virus (EBV) infection, especially undifferentiated non-keratinized histology. EBV DNA quantification through nasopharyngeal brushing was previously reported to be not related to disease stage. This study aimed to reinvestigate the relationship of EBV viral load in tumor tissue with tumor extensiveness by more accurate EBV DNA quantification through microscopically confirmed tumor cells from nasopharyngeal biopsy. Method: The specimens for EBV DNA quantification were derived from histopathology slides which were pre-treated following the QIAsymphony® SP protocol for tissue DNA extraction. Then, the extracted DNA underwent real-time polymerase chain reaction (RT-PCR) using the artus® EBV RG PCR Kit for EBV DNA quantification. The tumor volume was determined by delineating the gross tumor based on 3D imaging of the patient’s nasopharynx. Result: Twenty-four subjects were included in this study. All subjects were stage III and above, with more males (75%) than females. EBV viral load in tumor cells was found to have no correlation to tumor volume both in local and nodal regions. The median local tumor volume was 81.3 cm3 ± 80 cm3. The median EBV viral load in tumor cells was 95,644.8 ± 224,758.4 copies/100 ng of DNA. The median nodal or regional tumor volume was 35.7 ± 73.63 cm3. Conclusion: EBV viral load from tumor cells from nasopharyngeal biopsy has no relationship with tumor extensiveness in nasopharyngeal cancer. The presence and amount of EBV in tumor cells did not translate into larger or smaller tumors. The EBV viral proteins and RNAs were perhaps more likely to confer some prognostic information due to the fact that those molecules were related to carcinogenesis.


Virology ◽  
2017 ◽  
Vol 507 ◽  
pp. 220-230 ◽  
Author(s):  
Lena N. Lupey-Green ◽  
Stephanie A. Moquin ◽  
Kayla A. Martin ◽  
Shane M. McDevitt ◽  
Michael Hulse ◽  
...  

Author(s):  
Ronan J. Kelly

PD-L1 upregulation occurs in approximately 40% of gastroesophageal cancers. However, unlike other solid tumors, there is minimal PD-L1 expressed on the cancer cells; rather, expression occurs predominantly on infiltrating myeloid cells. Preliminary clinical data involving single-agent PD-1/PD-L1 inhibitors in metastatic gastroesophageal cancer have reported response rates of 22%–27% for patients with PD-L1+ tumors and 10%–17% for unselected patients. The phase III ONO-4538-12 (ATTRACTION 2) trial has demonstrated an improved overall survival for nivolumab compared with placebo for patients with heavily pretreated gastric cancer. In the future, we will need better biomarkers to select those most likely to respond and/or identify patients who may need combination immunotherapeutics or alternate strategies. A number of subsets of gastric cancer with different immune signatures, most notably tumors positive for Epstein-Barr virus and microsatellite instability, have been identified, with approximately 50% and 94% PD-L1+ staining seen on tumor cells and immune cells in the EBV subtype and approximately 33% and 45% PD-L1+ staining seen on tumor cells and immune cells in MSI high tumors. Both subtypes demonstrate PD-L1+ immune cells with tumor-infiltrating patterns, unlike the more commonly seen PD-L1+ immune cells at the invasive margin. PD-L2 expression has been reported in 52% of esophageal adenocarcinomas but little is known about the expression of other immune checkpoints. Additional factors that suggest gastroesophageal cancers may respond to checkpoint inhibition include the high somatic mutation burden and the link with chronic inflammation. Here we provide a comprehensive review of the checkpoint inhibitor data published to date in advanced esophagogastric cancers and rationalize how the immune microenvironment in these diverse tumors can explain response or resistance to immunotherapeutics.


2017 ◽  
Vol 241 ◽  
pp. 24-33 ◽  
Author(s):  
A.E. Greijer ◽  
O. Ramayanti ◽  
S.A.W.M. Verkuijlen ◽  
Z. Novalić ◽  
H. Juwana ◽  
...  

2001 ◽  
Vol 75 (13) ◽  
pp. 6235-6241 ◽  
Author(s):  
Barbara Wensing ◽  
Albert Stühler ◽  
Peter Jenkins ◽  
Martine Hollyoake ◽  
Claudio Elgueta Karstegl ◽  
...  

ABSTRACT Most of the Epstein-Barr virus genome in latently infected cells is in a standard nucleosomal structure, but the region encompassingoriP and the Epstein-Barr virus-encoded small RNA (EBER) genes shows a distinctive pattern when digested with micrococcal nuclease. This pattern corresponds to a previously mapped nuclear matrix attachment region. Although the EBER genes are adjacent to oriP, there is only a two- to fourfold effect oforiP on EBER expression. However, sequences containing a consensus ATF site upstream of EBER1 are important for EBER1 expression.


2021 ◽  
Vol 9 (4) ◽  
pp. 778
Author(s):  
Takayuki Murata

The immune system has evolved as a complex and efficient means of coping with extrinsic materials, such as pathogens and toxins, as well as intrinsic abnormalities, such as cancers. Although rapid and timely activation of the immune system is obviously important, regulated downregulation of the system is almost as significant as activation to prevent runaway immunity, such as allergies and hypercytokinemia. Therefore, the immune checkpoint programmed cell death 1 (PD-1)/programmed cell death ligand 1 (PD-L1) pathway is beneficial for the host. On the other hand, pathogens have evolved to evade host immunity by taking advantage of the PD-1/PD-L1 pathway. This review is focused on human herpesviruses, such as herpes simplex virus (HSV), cytomegalovirus (CMV), and Epstein–Barr virus (EBV), which cause various types of disorders, and their relationships with the PD-1/PD-L1 pathway. Understanding such relationships will be useful for developing preventative and therapeutic methods for disorders caused by herpesviruses.


Sign in / Sign up

Export Citation Format

Share Document