Functional characterization of circulating tumor cells with a prostate-cancer-specific microfluidic device.

Cancer metastasis accounts for the majority of cancer-related deaths owing to poor response to anticancer therapies. Molecular understanding of metastasis-associated drug resistance remains elusive due to the scarcity of available tumor tissue. Isolation of circulating tumor cells (CTCs) from the peripheral blood of patients has emerged as a valid alternative source of tumor tissue that can be subjected to molecular characterization.

Taxane-induced blockade to nuclear accumulation of the androgen receptor predicts clinical responses in metastatic prostate cancer.

Prostate cancer progression requires active androgen receptor (AR) signaling which occurs following translocation of AR from the cytoplasm to the nucleus. Chemotherapy with taxanes improves survival in patients with castrate resistant prostate cancer (CRPC). Taxanes induce microtubule stabilization, mitotic arrest, and apoptotic cell death, but recent data suggest that taxanes can also affect AR signaling.

Farnesyl transferase expression determines clinical response to the docetaxel-lonafarnib combination in patients with advanced malignancies.

Background: Lonafarnib (LNF) is a protein farnesyl transferase (FTase) inhibitor that has shown synergistic activity with taxanes in preclinical models and early stage clinical trials. Preclinical findings suggested tubulin acetylation and FTase expression levels may be important determinants of drug sensitivity that would help identify patient populations more likely to benefit from this regimen. This pilot study evaluated the biological effects of LNF and docetaxel (DTX) combination therapy in refractory solid tumors by comparing pretreatment and post-treatment tumor biopsies.

Alphavirus Entry and Membrane Fusion.

The study of enveloped animal viruses has greatly advanced our understanding of the general properties of membrane fusion and of the specific pathways that viruses use to infect the host cell. The membrane fusion proteins of the alphaviruses and flaviviruses have many similarities in structure and function. As reviewed here, alphaviruses use receptor-mediated endocytic uptake and low pH-triggered membrane fusion to deliver their RNA genomes into the cytoplasm.

The protein farnesyltransferase regulates HDAC6 activity in a microtubule-dependent manner.

The cytoplasmic deacetylase HDAC6 is an important regulator of cellular pathways that include response to stress, protein folding, microtubule stability, and cell migration, thus representing an attractive target for cancer chemotherapy. However, little is known about its upstream regulation. Our previous work has implicated HDAC6 as a new protein target for the farnesyltransferase inhibitors (FTIs), although HDAC6 lacks a farnesylation motif.

Second-site revertants of a Semliki Forest virus fusion-block mutation reveal the dynamics of a class II membrane fusion protein.

The alphavirus Semliki Forest virus (SFV) infects cells through low-pH-induced membrane fusion mediated by the E1 protein, a class II virus membrane fusion protein. During fusion, E1 inserts into target membranes via its hydrophobic fusion loop and refolds to form a stable E1 homotrimer. Mutation of a highly conserved histidine (the H230A mutation) within a loop adjacent to the fusion loop was previously shown to block SFV fusion and infection, although the mutant E1 protein still inserts into target membranes and forms a homotrimer.

A conserved histidine in the ij loop of the Semliki Forest virus E1 protein plays an important role in membrane fusion.

The enveloped alphavirus Semliki Forest virus (SFV) infects cells via a low pH-triggered membrane fusion reaction mediated by the E1 protein. E1 is a class II fusion protein that contains the hydrophobic fusion peptide loop and converts to a stable homotrimer during the fusion reaction. Intriguingly, the fusion loop is closely associated with a loop connecting the i and j beta-strands.