Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:3.1.3.16 (
calcineurin
)
17,112
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Liver transplantation has been the treatment of choice for end-stage liver disease since 1983. Cancer has emerged as a major long-term cause of death for liver transplant recipients. Many retrospective studies that have explored standardized incidence ratio have reported increased rates of solid organ cancers post-liver transplantation; some have also studied risk factors. Liver transplantation results in a two to five-fold mean increase in the rate of solid organ cancers. Risk of head and neck, lung, esophageal, cervical cancers and
Kaposi's sarcoma
is high, but risk of colorectal cancer is not clearly demonstrated. There appears to be no excess risk of developing breast or prostate cancer. Environmental risk factors such as viral infection and tobacco consumption, and personal risk factors such as obesity play a key role, but recent data also implicate the role of
calcineurin
inhibitors, whose cumulative and dose-dependent effects on cell metabolism might play a direct role in oncogenesis. In this paper, we review the results of studies assessing the incidence of non-skin solid tumors in order to understand the mechanisms underlying solid cancers in post-liver transplant patients and, ultimately, discuss how to prevent these cancers. Immunosuppressive protocol changes, including a calcineurin inhibitor-free regimen, combined with dietary guidelines and smoking cessation, are theoretically the best preventive measures.
...
PMID:Solid, non-skin, post-liver transplant tumors: Key role of lifestyle and immunosuppression management. 2675 88
Malignancy is the second most common single cause of death observed in organ transplant recipients. The excess cancer risk is related to intensity and duration of immunosuppressive therapy and inversely to recipient age. Immunodeficiency and (chronic/oncogenic) viral infections together constitute a major risk. Nonmelanoma skin cancer,
Kaposi sarcoma
, and posttransplant lymphoproliferative disease have standardized incidence ratios exceeding 10- or 50-fold. The mammalian target of rapamycin (mTOR) inhibitors, sirolimus and everolimus, are increasingly used after organ transplantation with potential advantages in virus-associated posttransplant malignancies as well as anti-cancer properties. Despite a seemingly clear mechanism of action and solid rationale for their use in cancer therapy, mTORis have met only modest success rates in clinical trials with advanced malignancies except for specific tumors, such as
Kaposi sarcoma
and mantle cell lymphoma. Because mTORis are primarily cytostatic, not cytotoxic, the observed clinical efficacy is a reflection of disease stabilization rather than tumor regression. Nonmelanoma skin cancers, in particular cutaneous squamous cell carcinoma, have the highest standardized incidence ratios in transplant recipients. Recent meta-analyses and randomized trials on secondary prevention of squamous cell carcinoma observed a reduction in cumulative tumor load, suggesting most benefit to be gained by early conversion to an mTOR inhibitor-based maintenance regime. There is ongoing debate on the mechanisms involved including withdrawal of the carcinogenic effects of
calcineurin
inhibitors and/or their impact on chronic (oncogenic) viral infections. At present, there is, however, insufficient evidence for the primary use of mTORis as protective agents against most other cancer types.
...
PMID:Cancer and mTOR Inhibitors in Transplant Recipients. 2754 65
Solid-organ transplant recipients are at higher risk of developing
Kaposi sarcoma
, which is a multicentric vascular neoplasm of lymphatic endothelium-derived cells. Reducing doses of immunosuppressive drugs and switching from
calcineurin
inhibitors to the mammalian target of rapamycin inhibitor rapamycin have been suggested as an effective first-line treatment modality in most patients. Herein, we report a 64-year-old renal transplant recipient who developed multiple cutaneous and visceral
Kaposi sarcoma
lesions 2 months after transplant. The patient showed no improvement, with progression of the disease until month 15 of the suggested therapy of rapamycin.
...
PMID:Kaposi Sarcoma in the Era of Rapamycin Remains a Therapeutic Challenge in Organ Transplant Recipients. 2952 86
The adaptor proteins, STING and MAVS, are components of critical pathogen-sensing pathways that induce innate immunity. Phosphorylation of either adaptor results in activation of the type I interferon pathway. How this phosphorylation is regulated and how it is manipulated by pathogens remain largely unknown. Here, we identified host
protein phosphatase
, Mg
2+
/Mn
2+
dependent 1G (PPM1G) as a negative regulator of innate immune pathways and showed that this host system is hijacked by
Kaposi's sarcoma
-associated herpesvirus (KSHV). Mechanistically, KSHV tegument protein ORF33 interacts with STING/MAVS and enhances recruitment of PPM1G to dephosphorylate p-STING/p-MAVS for immunosuppression. Inhibition of PPM1G expression improves the antiviral response against both DNA and RNA viruses. Collectively, our study shows that PPM1G restricts both cytosolic DNA- and RNA-sensing pathways to naturally balance the intensity of the antiviral response. Manipulation of PPM1G by KSHV provides an important strategy for immune evasion.
...
PMID:PPM1G restricts innate immune signaling mediated by STING and MAVS and is hijacked by KSHV for immune evasion. 3321 31
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