Atmospheric Pressure Photoionization Tandem Mass Spectrometry of Androgens in Prostate Cancer

Androgen deprivation therapy is the most common treatment option for advanced prostate cancer. Almost all prostate cancers recur during androgen deprivation therapy, and new evidence suggests that androgen receptor activation persists despite castrate levels of circulating androgens. Quantitation of tissue levels of androgens is critical to understanding the mechanism of recurrence of prostate cancer during androgen deprivation therapy. A liquid chromatography atmospheric pressure photoionization tandem mass spectrometric method was developed for quantitation of tissue levels of androgens. Quantitation of the saturated keto-steroids dihydrotestosterone and 5-α-androstanedione required detection of a novel parent ion, [M + 15]+. The nature of this parent ion was explored, and the method was applied to prostate tissue and cell culture with comparison to results achieved using electrospray ionization

Cooperation rates: overall and stratified by race (%).

<p>Cooperation rates: overall and stratified by race (%).</p

Associations between statin use and prostate cancer aggressiveness, overall and stratified by race and additionally adjusted for education, income and family history of prostate cancer. from Statin Use and Prostate Cancer Aggressiveness: Results from the Population-Based North Carolina–Louisiana Prostate Cancer Project

Logistic regression analysis of associations between statin use and prostate cancer aggressiveness, additionally adjusted for education, income and family history of prostate cancer.</p

Odds ratios for participation according to specific characteristics in multiple logistic regression models, stratified by race and study phase.

<p>The 40–59 year age group was the referent category for age in all models.</p

Flow diagram for the recruitment process of the PCaP study, LA cohort.

<p>^<b>a</b> Diagnosing physicians provided consent to contact 98% of AA and 96% of CA potential subjects in pre-K and 97% of AA and 96% of CA in post-K. ^b The reasons included: i) They changed their mind about enrollment after a visit was scheduled; ii) The scheduled interview ended up being cancelled. ^c The total number of ineligible, enrolled, refused and uncontacted cases were 273, 1234, 754 and 27, respectively.</p

Reasons cited for refusal among eligible research subjects contacted in the PCaP-LA cohort, stratified by race.

<p>First rows indicate counts, second rows indicate percentages (%).</p

Individual mouse CWR-R1 tumor volume (cm³) trajectories and predicted mean tumor volumes from each cohort.

<p>Tumors were measured using digital calipers and volumes calculated from day 14 to day 160 after CWR-R1 cell inoculation. Tumor volumes, LacZ (A, n = 22), LacZ+T (B, n = 21), ARΔTR (C, n = 21) or ARΔTR+T (D, n = 21), are shown from day 21 when growth began through day 96 beyond which only 1 mouse in each group remained. Mixed modeling statistical analysis showed a statistically significant difference among the 4 groups. ARΔTR-transduced CWR-R1 tumor growth rates were reduced compared to LacZ controls in the absence (p = 0.01, panel A vs. C) or presence (p = 0.0004, panel C vs. D) of T. (E) Predicted mean CWR-R1 tumor volumes (cm³) were plotted against time of first tumor harvest for the LacZ+T (open squares), LacZ (open diamonds), ARΔTR+T (solid circles) and ARΔTR (open circles) groups. ARΔTR-expressing CWR-R1 tumors (circles) exhibit decreased growth rates compared to LacZ-transduced CWR-R1 control cells.</p

Reasons for ineligibility^d of contacted patients in the PCaP-LA cohort, stratified by race and study phase.

<p>First rows indicate counts, second rows indicate percentages (%).</p

Odds ratios for participation according to specific characteristics in multiple logistic regression models, stratified by race.

<p>The 40–59 year age group was the referent category.</p

Log-Rank Test p-values in Order of Stepdown Pair-Wise Comparisons of Overall Survival Family-Wise Error Rate (FWR) Controlled p-values.

<p>Log-Rank Test p-values in Order of Stepdown Pair-Wise Comparisons of Overall Survival Family-Wise Error Rate (FWR) Controlled p-values.</p