The therapeutic effects of rGel/BLyS fusion toxin in in vitro and in vivo models of mantle cell lymphoma

Dysfunction of Cellular Proteostasis in Parkinson's Disease

Despite decades of research, current therapeutic interventions for Parkinson’s disease (PD) are insufficient as they fail to modify disease progression by ameliorating the underlying pathology. Cellular proteostasis (protein homeostasis) is an essential factor in maintaining a persistent environment for neuronal activity. Proteostasis is ensured by mechanisms including regulation of protein translation, chaperone-assisted protein folding and protein degradation pathways. It is generally accepted that deficits in proteostasis are linked to various neurodegenerative diseases including PD. While the proteasome fails to degrade large protein aggregates, particularly alpha-synuclein (α-SYN) in PD, drug-induced activation of autophagy can efficiently remove aggregates and prevent degeneration of dopaminergic (DA) neurons. Therefore, maintenance of these mechanisms is essential to preserve all cellular functions relying on a correctly folded proteome. The correlations between endoplasmic reticulum (ER) stress and the unfolded protein response (UPR) that aims to restore proteostasis within the secretory pathway are well-established. However, while mild insults increase the activity of chaperones, prolonged cell stress, or insufficient adaptive response causes cell death. Modulating the activity of molecular chaperones, such as protein disulfide isomerase which assists refolding and contributes to the removal of unfolded proteins, and their associated pathways may offer a new approach for disease-modifying treatment. Here, we summarize some of the key concepts and emerging ideas on the relation of protein aggregation and imbalanced proteostasis with an emphasis on PD as our area of main expertise. Furthermore, we discuss recent insights into the strategies for reducing the toxic effects of protein unfolding in PD by targeting the ER UPR pathway.

Malignancies in systemic lupus erythematosus: a 2015 update

PURPOSE OF REVIEW

Patients with systemic lupus erythematosus (SLE) have altered incidences of certain malignancies as compared with the general population. This review summarizes the recent literature on risk of malignancy in SLE and proposed mechanisms for these altered susceptibilities.

RECENT FINDINGS

Recent studies have confirmed previous data showing an increased risk of non-Hodgkin's lymphoma, lung, liver, vulvar/vaginal, and thyroid malignancies, whereas demonstrating a decreased risk of breast and prostate cancer. Lymphomagenesis in SLE has been linked to increased activity of multiple inflammatory cytokines as well as possible viral diseases. The decreased rates of hormone-sensitive cancers, such as breast and prostate, are speculated to be related to the presence of lupus autoantibodies and downregulation of certain proteins in SLE. This knowledge has been utilized to investigate new therapeutic modalities for these malignancies.

SUMMARY

Recent data confirm previously reported altered malignancy rates in SLE. Most striking in recent years are publications further elucidating mechanisms underlying cancer development in SLE, and subsequent investigations of potential therapeutics modulating these pathways.

Anti-tumor activities and apoptotic mechanism of ribosome-inactivating proteins

Ribosome-inactivating proteins (RIPs) belong to a family of enzymes that attack eukaryotic ribosomes and potently inhibit cellular protein synthesis. RIPs possess several biomedical properties, including anti-viral and anti-tumor activities. Multiple RIPs are known to inhibit tumor cell proliferation through inducing apoptosis in a variety of cancers, such as breast cancer, leukemia/lymphoma, and hepatoma. This review focuses on the anti-tumor activities of RIPs and their apoptotic effects through three closely related pathways: mitochondrial, death receptor, and endoplasmic reticulum pathways.

Role of BAFF/BAFF-R axis in B-cell non-Hodgkin lymphoma

B-cell activating factor (BAFF), as a member of the tumor necrosis factor (TNF) ligand family, plays important roles in B-cell homeostasis, tolerance, and malignancy. BAFF binds to three receptors of TNF, TACI, BCMA and BAFF-receptor (BAFF-R). In particular, the BAFF/BAFF-R pathway is crucial to the survival and growth of mature normal and malignant B-cells. BAFF is displayed on the cell surface or is released in a soluble form after cleavage from the plasma membrane. BAFF-R as the main BAFF receptor is expressed mainly on B-cells. Aberrant BAFF expression was found in malignant B-cells from B-cell non-Hodgkin lymphoma (B-NHL) patients, which protects these cells from spontaneous or drug-induced apoptosis and stimulated NF-κB activation via autocrine and/or paracrine pathways. However, the mechanisms involved in the gene expression and regulation of BAFF or BAFF-R has not been elucidated. More importantly, the design of reagents able to counteract BAFF/BAFF-R pathways may be of therapeutic value for B-NHL. Results of ongoing clinical trials with BAFF or BAFF-R antagonists are eagerly awaited.