Health-related quality of life, anxiety and depression in the diagnostic phase of suspected cancer, and the influence of diagnosis.

BACKGROUND: Undergoing diagnostic evaluation for cancer has been associated with a high prevalence of anxiety and depression and affected health-related quality of life (HRQoL). The aims of this study were to assess HRQoL, anxiety, and depression pre- and post-diagnosis in patients undergoing diagnostic evaluations for cancer due to non-specific symptoms; to examine changes over time in relation to final diagnosis (cancer yes/no); and to assess the predictive value of pre-diagnostic psychological, socio-demographic and clinical factors. METHODS: A prospective, multicenter survey study of patients suspected to have cancer based on non-specific symptoms was performed. Participants completed the EORTC-QLQ-C30 quality of life scale, HADS, SOC-13 and self-rated health before and after completing diagnostic evaluations. Intra- and inter-group differences between patients diagnosed with cancer versus patients with non-cancer diagnoses were calculated. The impact of baseline psychological, socio-demographic, and medical factors on HRQoL, anxiety and depression at follow-up was explored by bootstrapped multivariate linear regression analyses and logistic regression analyses. RESULTS: A total of 838 patients participated in this study; 679 (81 %) completed the follow-up. Twenty-two percent of the patients received a cancer diagnosis at the end of the follow-up. Patients presented initially with a high burden of symptoms and affected role and emotional functioning and global health/QL, irrespective of diagnosis. The prevalence of clinical anxiety prior to knowledge of the diagnosis was 32 % in patients with cancer and 35 % in patients who received a non-cancer diagnosis. HRQoL and anxiety improved after diagnosis, and a larger improvement was seen in patients who received a non-cancer diagnosis. There were no intra- or inter-group differences in the depression scores. The strongest predictors of global QL, anxiety, and depression after a known diagnosis were baseline scores, co-morbidity and poor self-rated health. CONCLUSIONS: Patients undergoing diagnostic evaluations for cancer based on non-specific symptoms experience a high prevalence of anxiety and affected quality of life prior to knowledge of the diagnosis. The predictive value of the baseline scores is important when assessing the psychological impact of undergoing diagnostic evaluations for cancer.

On-bead chemical synthesis and display of phosphopeptides for affinity pull-down proteomics.

We describe a new method for phosphopeptide proteomics based on the solid-phase synthesis of phosphopeptides on beads suitable for affinity pull-down experiments. Peptide sequences containing the Bad Ser112 and Ser136 phosphorylation motifs were used as bait in affinity pull-down experiments to determine their ability to bind 14-3-3 proteins. Support-bound peptides were assembled directly on the solid support (PEGA) by standard solid-phase synthesis through a BAL-type handle. The peptides were varied in length and sequence. This synthetic strategy also allowed introduction of a soft electrophile (aldehyde) at the C terminus for potential activity-based proteomics. The synthetic support-bound Bad phosphopeptides were able to pull down 14-3-3zeta. Furthermore, Bad phosphopeptides bound endogenous 14-3-3 proteins, and all seven members of the 14-3-3 family were identified by mass spectrometry. In control experiments, none of the unphosphorylated Bad peptides bound transfected 14-3-3zeta or endogenous 14-3-3. We conclude that the combined synthesis and display of phosphopeptides on-bead is a fast and efficient method for affinity pull-down proteomics.

Thiophene backbone amide linkers, a new class of easily prepared and highly acid-labile linkers for solid-phase synthesis.

Solid-phase synthesis is of tremendous importance for small-molecule and biopolymer synthesis. Linkers (handles) that release amide-containing products after completion of solid-phase synthesis are widely used. Here we present a new class of highly acid-labile backbone amide linkers (BAL handles) based on 3,4-ethylenedioxythiophene (EDOT), which we have termed T-BAL. These thiophene linkers are synthesized in three convenient steps from commercially available EDOT. In the linker design, the spacer was introduced to the EDOT core either via a carbon-carbon bond or via a thioether linkage. Introduction of the spacer via a C-C bond was performed by a chemoselective Negishi coupling without transient protection of the aldehyde group to provide the T-BAL1 handle. Introduction via a thioether linkage was performed by a facile nucleophilic aromatic substitution between the brominated EDOT aldehyde and unprotected mercapto acids to provide T-BAL2 and T-BAL3 handles. The minimal use of protecting groups gave the corresponding linker molecules in few synthetic steps and in good yields. After anchoring of the linker to a polymeric support, introduction of the first amino acid was achieved by reductive amination, giving a secondary amine. A following acylation of the secondary amine with a symmetrical amino acid anhydride resulted in a backbone amide linkage between the handle and the growing substrate (e.g., peptide chain). After solid-phase synthesis, the substrates could be released from the resin by either low acid conditions using 1% TFA in CH2Cl2 or high acid conditions such as 50% TFA in CH2Cl2. Peptide thioesters could be released from the T-BAL1 handle under very mild conditions using aqueous acetic acid. Tert-butyl based protecting groups, tert-butyl esters, tert-butyl ethers, and Boc groups, as well as dimethyl acetals were relatively stable to these mild conditions for release of the peptides.