The janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway is associated with the regulation of essential cellular mechanisms, such as proliferation, invasion, survival, inflammation, and immunity. Aberrant JAK/STAT signaling contributes to cancer progression and metastatic development. STAT proteins play an essential role in the development of cervical cancer, and the inhibition of the JAK/STAT pathway may be essential for enhancing tumor cell death. Persistent activation of different STATs is present in a variety of cancers, including cervical cancer, and their overactivation may be associated with a poor prognosis and poor overall survival. The oncoproteins E6 and E7 play a critical role in the progression of cervical cancer and may mediate the activation of the JAK/STAT pathway. Inhibition of STAT proteins appears to show promise for establishing new targets in cancer treatment. The present review summarizes the knowledge about the participation of the different components of the JAK/STAT pathway and the participation of the human papillomavirus (HPV) associated with the process of cellular malignancy.
Cervical cancer is one of the most prevalent gynaecological malignancies worldwide and is related to human papillomavirus (HPV) infection, viral persistence, progression, and invasion. Therefore, the immune response is linked to HPV status. Natural killer (NK) cells play a central role against virus-infected cells and tumours through a delicate balance between activating and inhibitory receptors and secretion of cytokines and chemokines. These cells also play a crucial role in tumour immunosurveillance. For these reasons, there is growing interest in harnessing NK cells as an immunotherapy for cervical cancer. These studies are diverse and include many strategies such as transferring activated autologous or allogeneic NK cells, improving the activation and cytolytic activity of NK cells using cytokines or analogues and modifying chimeric antigen receptors to increase specificity and targeting NK cells. However, research regarding the application of NK cells in immunotherapy is limited. This article focuses on recent discoveries about using NK cells to prevent and treat cervical cancer and the possibility of cellular immunotherapy becoming one of the best strategies to exploit the immune system to fight tumours.
A central characteristic of many types of cancer is altered energy metabolism processes such as enhanced glucose uptake and glycolysis and decreased oxidative metabolism. The regulation of energy metabolism is an elaborate process involving regulatory proteins such as HIF (pro-metastatic protein), which reduces oxidative metabolism, and some other proteins such as tumour suppressors that promote oxidative phosphorylation. In recent years, it has been demonstrated that signal transducer and activator of transcription (STAT) proteins play a pivotal role in metabolism regulation. STAT3 and STAT5 are essential regulators of cytokine- or growth factor-induced cell survival and proliferation, as well as the crosstalk between STAT signalling and oxidative metabolism. Several reports suggest that the constitutive activation of STAT proteins promotes glycolysis through the transcriptional activation of hypoxia-inducible factors and therefore, the alteration of mitochondrial activity. It seems that STAT proteins function as an integrative centre for different growth and survival signals for energy and respiratory metabolism. This review summarises the functions of STAT3 and STAT5 in the regulation of some metabolism-related genes and the importance of oxygen in the tumour microenvironment to regulate cell metabolism, particularly in the metabolic pathways that are involved in energy production in cancer cells.
Amyloid-beta oligomers (AβO) have been proposed as the most potent neurotoxic and inflammation inducers in Alzheimer’s disease (AD). AβO contribute to AD pathogenesis by impairing the production of several cytokines and inflammation-related signaling pathways, such as the Janus kinases/signal transducer of transcription factor-3 (JAK/STAT3) pathway. STAT3 modulates glial activation, indirectly regulates Aβ deposition, and induces cognitive decline in AD transgenic models. However, in vivo studies using an AβO microinjection rat model have not yet explored STAT3 role. The main purpose of this study was to elucidate if a single microinjection of AβO could promote an increased expression of STAT3 in glial cells favoring neuroinflammation and neurodegeneration. We designed a model of intrahippocampal microinjection and assessed glial activation, cytokines production, STAT3 expression, and neurodegeneration in time. Our results showed robust expression of STAT3 in glial cells (mainly in astrocytes) and neurons, correlating with neuronal death in response to AβO administration. A STAT3 inhibition assay conducted in rat primary hippocampal cultures, suggested that the induction of the transcription factor by AβO in astrocytes leads them to an activation state that may favor neuronal death. Notwithstanding, pharmacological inhibition of the JAK2/STAT3 pathway should be focused on astrocytes because it is also essential in neurons survival. Overall, these findings strongly suggest the participation of STAT3 in the development of neurodegeneration.
The Janus kinase (JAK)/signal transducer and activator of transcription (STAT) signaling pathway constitutes a rapid signaling module from the cell surface to the nucleus, and activates different cellular responses, such as proliferation, survival, migration, invasion, and inflammation. When the JAK/STAT pathway is altered, it contributes to cancer progression and metastasis. STAT proteins play a central role in developing cervical cancer, and inhibiting the JAK/STAT signaling may be necessary to induce tumor cell death. Several cancers show continuous activation of different STATs, including cervical cancer. The constitutive activation of STAT proteins is associated with a poor prognosis and overall survival. The human papillomavirus (HPV) oncoproteins E6 and E7 play an essential role in cervical cancer progression, and they activate the JAK/STAT pathway and other signals that induce proliferation, survival, and migration of cancer cells. Moreover, there is a crosstalk between the JAK/STAT signaling cascade with other signaling pathways, where a plethora of different proteins activate to induce gene transcription and cell responses that contribute to tumor growth. Therefore, inhibition of the JAK/STAT pathway shows promise as a new target in cancer treatment. In this review, we discuss the role of the JAK/STAT pathway components and the role of the HPV oncoproteins associated with cellular malignancy through the JAK/STAT proteins and other signaling pathways to induce tumor growth.
IL-2 receptor (IL-2R) signalling is critical for normal lymphocyte proliferation, but its role in cervical cancer is not fully understood. The receptor is composed of three chains: IL-2α, IL-2β, and IL-2γ. Intracellular signalling is initiated by ligand-induced heterodimerization of the IL-2βand IL-2γchains, resulting in the activation of multiple intracellular kinases. Recently, IL-2R was shown to be expressed on nonhaematopoietic cells, especially on several types of tumour cells. However, the function of this receptor on malignant cells has not been clearly defined. The expression of IL-2R and the production of IL-2 in cervical cancer cells have been documented as well as expression of molecules of the JAK-STAT pathway. In the current review we have highlighted the differences in the responses of molecules downstream from the IL-2R in normal lymphocytes and tumour cells that could explain the presence of tumour cells in an environment in which cytotoxic lymphocytes also exist and compete and also the effect of different concentrations of IL-2 that could activate effector cells of the immune system cells, which favour the elimination of tumour cells, or concentrations that may promote a regulatory microenvironment in which tumour cells can easily grow.