James T. Lin

Curcumin–glutathione interactions and the role of human glutathione S-transferase P1-1

Curcumin (diferuloylmethane), a yellow pigment of turmeric with antioxidant properties has been shown to be a cancer preventative in animal studies. It contains two electrophilic alpha, beta-unsaturated carbonyl groups, which can react with nucleophilic compounds such as glutathione (GSH), but formation of the GSH-curcumin conjugates has not previously been demonstrated. In the present studies, we investigated the reactions of curcumin with GSH and the effect of recombinant human glutathione S-transferase(GST)P1-1 on reaction kinetics. Glutathionylated products of curcumin identified by FAB-MS and MALDI-MS included mono- and di-glutathionyl-adducts of curcumin as well as cyclic rearrangement products of GSH adducts of feruloylmethylketone (FMK) and feruloylaldehyde (FAL). The presence of GSTP1-1 significantly accelerated the initial rate of GSH-mediated consumption of curcumin in 10 mM potassium phosphate, pH 7.0, and 1 mM GSH. GSTP1-1 kinetics determined using HPLC indicated substrate inhibition (apparent K(m) for curcumin of 25+/-11 microM, and apparent K(i) for curcumin of 8+/-3 microM). GSTP1-1 was also shown to catalyze the reverse reaction leading to the formation of curcumin from GSH adducts of FMK and FAL.

Cancer in an incarcerated population

The challenge posed to prison health systems in the U.S. by an immense incarcerated population is significant. However, the patterns of presentation and associated mortality of cancer among the incarcerated population is unknown.

Epiphora induced by intermittent docetaxel (taxotere) in patients with non-small cell lung cancer.

Docetaxel is a chemotherapeutic agent that is frequently used in the treatment of cancers of the breast, lung, and prostate. – 3] Commonly observed side effects include fever, alopecia, nausea, vomiting, diarrhea, stomatitis, neutropenia, anemia, peripheral neuropathy, fluid retention, and hypersensitivity reactions. Epiphora, or excessive tearing, is a recently recognized side effect of treatment with docetaxel. To date, epiphora has primarily been reported in women receiving weekly docetaxel for the treatment of metastatic breast cancer. – 7] We report two patients with stage IV nonsmall cell lung cancer (NSCLC) who developed epiphora while receiving intermittent therapy with docetaxel.

Urinary exosomes as a stable source of mRNA for prostate cancer analysis.

174 Background: Exosomes are novel lipid bilayer vesicles that are released into biofluids such as urine and carry high integrity RNA from the parent cell which they were derived. Due to their unique stability and the fact that they contain prostate specific mRNA transcripts, we examined their potential as a non-invasive source of mRNA biomarkers for prostate cancer analysis. METHODS Following a Columbia University approved IRB protocol, random urine samples were collected from 163 men who were stratified into 4 groups: biopsy negative (Bx Neg, n=39), biopsy positive (Bx Pos, n=47), post-radical prostatectomy (RP, n=37) and controls (males <35 yrs, n=40). Urine samples were stored at 4°C and 0.8 μm filtration was used to remove whole cells and debris. Urinary exosomal RNA was isolated using our in-house technique. RT-qPCR was used to analyze PSA, PCA3, androgen receptor (AR), survivin, NCOA2, RAD21, transmembrane protease serine 2 (TMPRSS2), ERG and TMPRSS2:ERG fusion at the mRNA level. RESULTS Mean serum PSA protein level and age were similar in the Bx Neg and Bx Pos groups. Relative quantitation (RQ) of genes standardized to the PSA gene revealed that ERG (P<0.005), PCA3 (P<0.005), TMPRSS2:ERG fusion (P<0.05), TMPRSS2 (P<0.05) and survivin (P<0.005) were significantly increased in the Bx Pos vs. Bx Neg group. TMPRSS2:ERG fusion events occurred in 68% of Bx Pos vs. 44% of Bx Neg patients and were present in only 5% of controls. No patient in the RP group had positive TMPRSS2:ERG detection; this finding was further supported by the loss of TMPRSS2:ERG expression for 4 Bx Pos patients following prostatectomy suggesting specificity of the fusion event to the prostate. CONCLUSIONS This study confirms urinary exosomes as a source of high quality RNA and showed significant differences in the expression of ERG, PCA3, TMPRSS2:ERG genes between the Bx Pos and Bx Neg groups. Our findings are consistent with previous studies based on tissue and post-prostate massage urinary cell analyses. The unique stability and yield of urinary exosomal RNA collected without a prostatic massage will hopefully simplify sample handing, obviate sample variability and patient discomfort inherent to prostate massage, and broaden the role of exosomes in future diagnostic testing.