Androphilic protein studied histochemically in stage D2 prostatic cancer

Pictet-Spengler condensations using 4-(2-aminoethyl)coumarins

Androgen-deprivation therapy (ADT) is only a palliative measure, and prostate cancer invariably recurs in a lethal, castration-resistant form (CRPC). Prostate cancer resists ADT by metabolizing weak, adrenal androgens to growth-promoting 5α-dihydrotestosterone (DHT), the preferred ligand for the androgen receptor (AR). Developing small-molecule inhibitors for the final steps in androgen metabolic pathways that utilize 17-oxidoreductases required probes that possess fluorescent groups at C-3 and intact, naturally occurring functionality at C-17. Application of the Pictet-Spengler condensation to substituted 4-(2-aminoethyl)coumarins and 5α-androstane-3-ones furnished spirocyclic, fluorescent androgens at the desired C-3 position. Condensations required the presence of activating C-7 amino or N,N-dialkylamino groups in the 4-(2-aminoethyl)coumarin component of these condensation reactions. Successful Pictet-Spengler condensation, for example, of DHT with 9-(2-aminoethyl)-2,3,6,7-tetrahydro-1H,5H,11H-pyrano[2,3-f]pyrido[3,2,1-ij]quinolin-11-one led to a spirocyclic androgen, (3R,5S,10S,13S,17S)-17-hydroxy-10,13-dimethyl-1,2,2',3',4,5,6,7,8,8',9,9',10,11,12,12',13,13',14,15,16,17-docosahydro-7'H,11'H-spiro-[cyclopenta[a]phenanthrene-3,4'-pyrido[3,2,1-ij]pyrido[4',3':4,5]pyrano[2,3-f]quinolin]-5'(1'H)-one. Computational modeling supported the surrogacy of the C-3 fluorescent DHT analog as a tool to study 17-oxidoreductases for intracrine, androgen metabolism.

Metastatic prostate cancer with normal level of serum prostate-specific antigen

The clinical and pathological features of metastatic prostate cancer with normal level of serum prostate-specific antigen (PSA) were investigated. Four patients with metastatic prostate cancer had serum PSA within the normal range at the diagnosis. All tumors were poorly-differentiated adenocarcinoma. Endocrine therapy was performed as the initial therapy in all patients. Despite subsequently treatment, all cases died of prostate cancer at 2, 8, 9 and 38 months. During disease progression, 3 of 4 patients had elevated serum markers such as carcinoembryonic antigen (CEA), CA19-9, CA15-3, CA125, neuron-specific enolase and pro-gastrin releasing peptide. Immunohistochemical examination of the initial biopsy specimens revealed that 4 and 3 cases were positive for CEA and chromogranin A, respectively. In advanced prostate cancer patients with low PSA level, those markers may aid in the follow up of disease.

Pattern of progression and survival in hormonally treated metastatic prostate cancer

BACKGROUND

Patients with prostate cancer generally respond to androgen ablation therapy, but progression to androgen-independence is frequently observed. To further evaluate disease progression, the pattern of progression and survival in hormonally treated metastatic prostate cancer was examined.

METHODS

One hundred and ninety-three patients with untreated metastatic prostate cancer (TxNxM ) who received endocrine therapy between 1986 and 1995 were included in the present study. The pattern of progression was evaluated in these patients.

RESULTS

One hundred and eighteen of the 193 patients (61.1%) had disease progression: 33 had local progression, 73 had distant progression and 12 had distant with local progression. Patients with only local progression had a longer interval to disease progression and longer survival than those with distant progression. The interval from disease progression to death in patients with local progression was longer than in those with distant progression. The patients whose prostate-specific antigen (PSA) had not been normalized 3 months after the start of endocrine therapy had a tendency to progression either into the prostate or into distant sites. Patients with extent of disease (EOD) scores of 3 and 4 progress, especially to distant sites, after endocrine treatment.

CONCLUSIONS

In untreated metastatic prostate cancer, patients with a poor response of PSA levels and patients with a high volume of bone metastasis (i.e. EOD 3, 4) were in the high-risk group for progression, especially to distant sites. Progression into distant sites was a poor prognostic factor for patients with recurrence to endocrine therapy.

Immunocytochemical assay for androgen receptors in prostate cancer: a prospective study of 63 cases with long-term follow-up

BACKGROUND

Numerous problems are associated with biochemical androgen receptor (AR) assay performance and interpretation in prostatic cancer. The purpose of this study was to determine if a novel immunocytochemical AR assay performed on intact tissue sections would prove useful in prognosticating endocrine response and survival.

METHODS

A prospective study was done on 63 prostatic carcinomas maintained in liquid nitrogen for over a decade. The study used the peroxidase-antiperoxidase system and a polyclonal anti-AR antibody.

RESULTS

Marked tissue and cellular heterogeneity of nuclear AR was apparent. A cut-off of 10% AR-positive cells maximized assay prognostic efficiency. Frequency of positivity was 48% and correlated significantly with endocrine response (p = 0.03), time to progression (p = 0.0016), and survival (p = 0.02), but not with grade, stage, or ethnicity.

CONCLUSIONS

This AR assay could be prognostically useful in the clinical management of prostate cancer and is suitable for use in the community hospital laboratory.

Immunohistochemical study of androgen receptor in benign hyperplastic and cancerous human prostates

Androgen receptor was detected immunohistochemically in benign as well as malignant prostatic tissues by using a monoclonal rat anti-human androgen receptor antibody (AN 1-15). In both benign and malignant cells, the androgen receptor was exclusively localized in nuclei. In hyperplastic prostate, the androgen receptor was stained in the glandular and the stromal cells. In the gland, cells facing the lumen were stained more intensively than those adjacent to the basal membrane. In cancer tissue, receptor-positive and -negative cancer cells were intermingled. The percent of strongly positive cancer cells was correlated inversely with grade. Relapsed cells showed a low population of strongly positive cells irrespective of grade.

Histochemical examination of expression of ras p21 protein and R 1881-binding protein in human prostatic cancers

Expression of ras p21 was examined with monoclonal antibody RASK-3 in normal, benign hyperplasic, and cancerous prostates. In patients with stage D2 disease who received endocrine therapy, the relation between ras p21 expression, response to therapy, and prognosis was studied. In these patients, R 1881-binding protein (androgen receptor and progestin-binding protein) was also examined. Non-cancerous cells and most cancer cells from stage A patients did not express ras p21, while expression increased with both higher staging and grading. Staging pelvic lymphadenectomy was done in some stage A2-C cases, and presence of nodal metastasis was correlated with ras p21 expressions in the primary tumours. In stage D2, there was no correlation between ras p21 expression and R 1881-binding protein. Response to therapy and survival did not correlate with expression of ras p21, but was influenced by presence of R 1881-binding protein.