New prognostic factors in prostatic carcinoma

Expression of matrix metalloproteinase-10 in non-metastatic prostate cancer: Correlation with an imbalance in cell proliferation and apoptosis

Matrix metalloproteinases (MMPs) are associated with cell invasion under various physiological and pathological conditions. Among MMPs, MMP-10 is reported to correlate with a high pT stage and progression in a variety of cancer types. However, the clinical and pathological significance of MMP-10 in human prostate cancer tissues remains unclear. This study aimed to clarify the role of MMP-10 in non-metastatic prostate cancer. Sixty-three specimens were obtained by radical prostatectomy. MMP-10 expression, Ki-67, CD34 and apoptotic cells were examined using an immunohistochemical technique and the terminal deoxynucleotidyl transferase-mediated nick end-labeling method. The proliferation index (PI), apoptotic index (AI), microvessel density (MVD) and cell renewal index (CRI=PI/AI) were calculated. The relationship between MMP-10 expression and clinicopathological features, as well as PI, AI, MVD and CRI were investigated. MMP-10 was mainly detected in cancer cell cytoplasm, and the proportion of MMP-10-expressing cancer cells (median 13.8%) was significantly higher (P<0.001) than non-tumoral gland cells (2.4%). Similarly, the proportion of MMP-10-expressing cancer cells was significantly higher (P=0.007) in stage pT3 (median 22.3%) than in pT2 (11.3%) tumors and was correlated with blood vessel invasion (P=0.025). In addition, its expression level correlated significantly with CRI (r=0.34, P=0.001), but not with PI, AI or MVD. Multivariate analysis identified MMP-10 expression to be closely associated with pT stage (OR 3.76, 95% CI 1.14-12.34, P=0.029). Our results suggest that the overexpression of MMP-10 produces an imbalance in cancer cell proliferation and apoptosis, thereby contributing to cancer cell progression of non-metastatic prostate cancer.

The androgen receptor directly targets the cellular Fas/FasL-associated death domain protein-like inhibitory protein gene to promote the androgen-independent growth of prostate cancer cells

Androgens provide survival signals to prostate epithelial cells, and androgen ablation induces apoptosis in the prostate gland. However, the molecular mechanisms of actions of the androgen-signaling pathway in these processes are not fully understood. Here, we report that androgens induced expression of the cellular Fas/FasL-associated death domain protein-like inhibitory protein (c-FLIP) gene, which is a potent inhibitor of Fas/FasL-mediated apoptosis. The androgen receptor was recruited to the promoter of the c-FLIP gene in the presence of androgens. We found that c-FLIP promoter contained multiple functional androgen response elements. In addition, we show that c-FLIP overexpression accelerated progression to androgen independence by inhibiting apoptosis in LNCaP prostate tumors implanted in nude mice. Our results suggest that the androgen receptor affects survival and apoptosis of prostate cells through regulation of the c-FLIP gene in response to androgens.

Blinded evaluation of reverse transcriptase-polymerase chain reaction prostate-specific antigen peripheral blood assay for molecular staging of prostate cancer

OBJECTIVES

The reverse transcriptase-polymerase chain reaction (RT-PCR)-prostate-specific antigen (PSA) assay to detect presumed occult micrometastatic prostate cancer has been controversial, and this molecular staging has been thought to be clinically useful by some groups but not others.

METHODS

We used a sensitive nested RT-PCR assay with specific primers derived from the PSA sequence and a very stringent two-step PCR protocol with denaturing temperature of 94 degrees C annealing and extension temperature of 68 degrees C. This method enabled us to detect PSA-expressing LNCaP prostate cancer (PC) cells as low as one cell of 10 million lymphocytes (1/10(7)). Ninety-six patients with PC were studied, including 85 before radical prostatectomy (RP), and 22 controls, including healthy men and women and men with benign prostatic hyperplasia.

RESULTS

In 85 patients undergoing RP, a minimum of two independent RT-PCR-PSA assays detected circulating prostate cells preoperatively in 27 patients (31.8%). Of 12 patients with locally advanced or advanced stage cancer, RT-PCR-PSA was positive in 5 (41.7%); of the 22 controls, no patient was RT-PCR-PSA positive. In 10 randomly selected cases, the RT-PCR product was confirmed as PSA by DNA sequencing. Of the 27 patients undergoing RP who were RT-PCR positive, 11 (40.7%) had non-organ-confined disease (pT3a or greater), and of the 58 patients who were RT-PCR negative, 32 (55.2%) had non-organ-confined disease. Patients with RT-PCR positive results also had lower margin positivity (9 of 27, 33.3%) than did patients with RT-PCR negative results (21 of 58, 36.2%). Finally, at a mean follow-up of 25.7 months, 5 (18.5%) of 27 RT-PCR positive patients had recurrence (PSA) compared with 14 (24.1%) of 58 RT-PCR negative patients.

CONCLUSIONS

On the basis of this blinded study, RT-PCR for PSA-expressing cells in 85 patients before RP is not related to clinical stage, age, race, grade, Gleason sum, serum PSA or prostatic acid phosphatase, tumor volume, or tumor multifocality. RT-PCR positivity did not predict pathologic stage or early PSA recurrence. A standardized RT-PCR assay needs to be developed to account for interlaboratory discrepancies.

Increased cell proliferation activity and decreased cell death are associated with the emergence of hormone-refractory recurrent prostate cancer

The tumour growth kinetics (cell proliferation and apoptosis) of ten hormone-refractory locally recurrent prostate cancers were compared with their matched untreated primary tumour specimens. All recurrent tumours had a higher cell proliferation activity, as defined by Ki-67 immunohistochemistry, than corresponding primary tumours from the same patients. The mean cell proliferation activity in recurrences (13.5 +/- 3.8 per cent) was over two times higher (P < 0.0001) than that in primary tumours (5.5 +/- 2.4 per cent), suggesting that cell clones which progress during androgen withdrawal are actively stimulated to proliferate. The mean percentage of apoptotic cells, as estimated by the in situ end-labelling technique, was 5.4 +/- 4.7 per cent in untreated primary tumours, whereas it was 2.3 +/- 1.5 per cent in locally recurrent tumours (P = 0.05). In all but two cases, the apoptotic index was lower in recurrent than in corresponding primary tumours, suggesting that recurrent prostate carcinomas are able to avoid apoptosis in the androgen-deprived environment. In conclusion, the clinical progression of prostate cancer during androgen withdrawal is associated with increased cell proliferation and decreased apoptosis.

Location of KAI1 on the short arm of human chromosome 11 and frequency of allelic loss in advanced human prostate cancer

BACKGROUND

We recently isolated the KAI1 gene, a metastasis suppressor gene for prostate cancer, from human chromosome region 11p13-cen-containing rat prostate cancer cells. The present study was performed to further locate the region of the KAI1 gene on the short arm of chromosome 11, and to examine whether loss of this region is significant during progression of human prostate cancer.

METHODS

The small portion of human chromosome 11 (i.e., 11p13-cen) was reintroduced into highly metastatic rat prostate cancer cells by using microcell-mediated chromosome transfer. Loss of heterozygosity (LOH) at polymorphic microsatellite loci on the human chromosome 11 was examined in human prostate cancer tissues.

RESULTS

The minimum region of human chromosome 11 that contained the KAI1 gene was located on the proximal region of 11p11.2 divided by the D11S554 locus. The percentage of LOH or allelic imbalance at the D11S1344 locus, which is located on the same region as the KAI1 locus, in metastasis tissues from autopsy cases who died from metastatic prostate cancer was 70% (7 of 10 informative cases), whereas the percentages in primary tumors from the same cases and from cases with clinically localized prostate cancer were 33% (3 of 9 informative cases) and 8% (1 of 12 informative cases), respectively.

CONCLUSIONS

These findings demonstrate a high frequency of LOH or allelic imbalance at the centromeric region of 11p, which contains the KAI1 gene in advanced prostate cancer.

Prognostic factors in patients with prostate cancer refractory to endocrine therapy: univariate and multivariate analyses including doubling times of prostate-specific antigen and prostatic acid phosphatase

Although several prognostic factors have been discussed, multivariate analysis that includes tumor marker doubling time has not yet been examined in patients with prostate cancer refractory to endocrine therapy. A number of conventional prognostic factors including doubling times of prostate-specific antigen and/or prostatic acid phosphatase were examined in 56 prostate cancer patients who were refractory to endocrine therapy, using univariate and multivariate analyses. On univariate analysis, 6 parameters (doubling times of prostate-specific antigen and prostatic acid phosphatase at the time of refractory status, performance status, duration from beginning of endocrine therapy to prostate-specific antigen/prostatic acid phosphatase failure, mode of recurrence, the presence or absence of prostate-specific antigen/prostatic acid phosphatase normalization, and alkaline phosphatase) were shown to be significant prognostic factors. On multivariate analysis, only performance status and doubling times of prostate-specific antigen and prostatic acid phosphatase were significant. These observations showed that the doubling times of prostate-specific antigen and prostatic acid phosphatase, calculated at the time of prostate-specific antigen/prostatic acid phosphatase failure by estimating serial prostate-specific antigen or prostatic acid phosphatase, were a valuable prognostic factor in patients with prostate cancer refractory to endocrine therapy.

Prognostic factors in patients with metastatic (stage D2) prostate cancer: experience from the Scandinavian Prostatic Cancer Group Study-2

PURPOSE

Nuclear texture reflects the overall structures of the chromatin organization. We recently reported the principles and prognostic importance of image analysis of nuclei from metastatic prostate cancer. Immunohistochemical up regulation of the adhesion molecule sialyl Lewis(x) is also reported to be a prognostic parameter. Presently we analyzed statistically the prognostic impact of these 2 new parameters compared to well-known clinical parameters in metastatic prostate cancer.

MATERIALS AND METHODS

Prognostic factors, such as sedimentation rate, alkaline and acid phosphatases, hemoglobin, testosterone, performance status, pain due to metastasis, T category, histological grade and patient age, were included in a multivariate Cox proportional hazards regression analysis based on 262 patients from the Scandinavian Prostatic Cancer Group Study-2. Extent of bone lesions, deoxyribonucleic acid ploidy, texture analysis and sialyl Lewis(x) molecules based on subsets of these 262 patients were also analyzed in the same multivariate model.

RESULTS

This test identified chromatin texture as the most important factor (p < 0.001), followed by reaction of the oligosaccharide sialyl Lewis(x) (p < 0.01). Among the routine clinical and laboratory data, sedimentation rate, alkaline phosphatase and hemoglobin (p < 0.05) showed prognostic importance. Performance status, pain due to metastasis and extent of bone lesions showed prognostic value in the univariate analysis (p < 0.05).

CONCLUSIONS

These data indicate that computerized nuclear texture analysis as well as up regulation of sialyl Lewis(x) molecules may be new important prognostic factors in metastatic prostate cancer. Furthermore the prognostic importance of sedimentation rate, alkaline phosphatase and hemoglobin was confirmed.

Alteration of the tumor suppressor gene p53 in a high fraction of hormone refractory prostate cancer

PURPOSE

We studied the role of p53 tumor suppressor gene alteration in prostate cancer progression by demonstrating a difference in abnormal p53 findings between early and hormone refractory disease.

MATERIALS AND METHODS

The study included p53 immunohistochemistry of 26 archival transurethral resection specimens from patients with radiation recurrent and hormone refractory disease, 27 untreated primary tumors and 8 untreated metastatic lesions. p53 mutation analysis of tumor deoxyribonucleic acid (DNA) from microdissected specimens was done by cold single strand conformational polymorphism and DNA sequencing.

RESULTS

Elevated p53 protein was present in 16 of 17 hormone refractory specimens (94%), 4 of 8 untreated metastatic tumors (50%) and 6 of 27 primary untreated tumors (22%). DNA analysis of representative specimens with elevated p53 confirmed p53 gene alterations in 9 of 11 cases (82%).

CONCLUSIONS

Our study revealed a clear progression of increased p53 alteration from untreated primary to hormone refractory disease (p < 0.00005).

Prognostic value of prostate-specific antigen minimum after orchidectomy in patients with stage C and D prostatic carcinoma

OBJECTIVE

To determine the significance of the minima of prostate-specific antigen (PSA) levels after orchidectomy in patients with advanced carcinoma of the prostate (stage C and D disease), to thereby discriminate patients who have a statistically significant difference in prognosis and thus individualize their adjuvant treatment.

PATIENTS AND METHODS

A retrospective analysis of 50 patients (mean age 75.8 years) with extracapsular prostate cancer (58% stage C, 42% stage D disease) was performed. PSA measurement and clinical assessment were continued at 3-monthly intervals until there was evidence of clinical progression. The minimum values of PSA were determined, the patients grouped at intervals of 1 ng/mL and the groups compared statistically on the basis of disease progression.

RESULTS

Serum PSA levels decreased in all patients to a minimum after 3-6 months. There was a statistically significant difference in the probability of, and time to, disease progression for PSA minima at 1 ng/mL and 10 ng/mL. Of the 13 patients in group 1 (with PSA minima < 1 ng/mL), 11 stayed in remission during a mean follow-up duration of 45.9 months. Of 25 patients in group 2 (with PSA minima between 1 and 10 ng/mL) 19 developed progression after a mean remission period of 16.7 months, while all 12 patients in group 3 (with PSA minima > 10 ng/mL) progressed after a mean remission period of 12.5 months.

CONCLUSION

Post-orchidectomy PSA minima are an excellent prognostic factor with significant predictive value. While patients in group 1 tend to have a favourable prognosis after orchidectomy alone, group 2 and 3 patients need adjuvant treatment as early as possible. Group 3 patients, with their high probability of early progression, also form a uniform cohort for studies concerning new therapeutic modalities. If the PSA minimum was included in further examinations, the results of treatment should improve.

Histopathological grading and DNA ploidy as prognostic markers in metastatic prostatic cancer

The present study compares the prognostic potential of tumour grade and DNA ploidy status in patients with advanced-stage prostatic cancer. Two outcome groups were selected on the basis of time to progression and survival after orchiectomy. A poor-outcome group consisted of 32 therapy-resistant patients who experienced disease progression during the first year after orchiectomy and subsequently death due to prostatic cancer during the following year. A good-outcome group consisted of 27 therapy-responsive patients who showed disease regression and no signs of progression during a 3 year follow-up. The primary tumours were graded twice according to WHO and Gleason classification systems by two pathologists. Final agreement between the pathologists was obtained after a consensus meeting. The analysis revealed no prognostic importance of the two histological classification systems (P = 0.62 and P = 0.70) and disclosed weak inter- and intra-observer reproducibility (kappa < 0.70). DNA ploidy analyses were performed by image cytometry on formalin-fixed, paraffin-embedded samples of the primary tumours. Overall, 48% of the tumours were diploid, 20% tetraploid and 32% anueploid. DNA ploidy status did not discriminate between the two outcome groups (P = 0.46). Histological grade and DNA ploidy showed no prognostic importance in patients with prostatic cancer and skeletal metastases.

High cell proliferation activity determined by DNA flow cytometry and prognosis in epidermoid lung carcinoma

DNA aneuploidy and high cell proliferation activity determined by DNA flow cytometry are known to be associated with poor prognosis in many human malignancies. The aim of the present study was to determine the long-term prognostic value of DNA ploidy and cell proliferation activity in lung cancer. The material consisted of samples from 290 paraffin-embedded lung cancers (171 epidermoid carcinomas, 62 small-cell carcinomas, 26 adenocarcinomas, and 31 others), of which DNA ploidy and cell proliferation activity as defined by S-phase fraction (SPF) was determined by DNA flow cytometry. DNA aneuploidy was found in 61% of the tumours and the mean (+/- SD) SPF was 13.6 +/- 9.5%. DNA aneuploidy was associated with a high T-stage (p < 0.05) in epidermoid carcinoma, but not in small-cell carcinoma or adenocarcinoma. DNA aneuploidy and high SPF were associated with poor survival in epidermoid carcinoma. However, only SPF (relative risk (RR) = 1.80), N-(RR = 2.46) and M-stages (RR = 2.17) were statistically significant predictors of survival according to multivariate analysis. Regression-tree analysis showed that the prognostic value of SPF was restricted to localized (M0-stage) epidermoid carcinoma. Neither DNA aneuploidy nor SPF was associated with survival in small-cell lung carcinoma. In conclusion, SPF is an independent prognostic factor in epidermoid lung carcinoma.

Morphologic and immunohistochemical changes in prostate cancer after preoperative hormonal therapy. A comparative study of radical prostatectomies

BACKGROUND

Estramustine phosphate (EMP) and flutamide (FL) were used as reversible preoperative hormonal drugs in the surgical treatment of patients with localized prostate cancer.

METHODS

The authors descriptive and quantitatively examined the morphologic and immunohistochemical changes in 40 of 200 step-sectioned radical prostatectomies, obtained after treatment with EMP (25 patients) and with FL (15 patients). Of these, 28 pretreatment needlecore biopsies were available.

RESULTS

Every specimen contained adenocarcinoma. Understaging was found in 50% of the cases and a higher Gleason score in 70%. Benign glands underwent atrophy and squamous metaplasia. Treated tumors showed cytoplasmic vacuolization, nuclear pyknosis, fibrosis and lymphocytic infiltrates. The EMP group had an 84% (P < 0.05) higher mean total regression score than the FL group. Estramustine phosphate induced a 56% (P < 0.05) and a 34% decrease in tumoral prostate specific antigen and prostate specific acid phosphatase intensity scores, respectively, versus 29% and 32% after FL. The mean proliferating cell nuclear antigen (PCNA) labeling index and the mean mitotic index of the EMP group were 52% (P < 0.05) and 70% (P < 0.05) lower than those measured in the FL group. Each FL-treated tumor and 92% of EMP-treated tumors expressed chromogranin A (ChrA); ChrA labeling correlated significantly with PCNA labeling. Seventy-six percent of EMP-treated specimens revealed venous thrombosis.

CONCLUSIONS

Estramustine phosphate induces important morphologic and immunohistochemical changes in prostate cancer with an apparent decrease of secretory and proliferative activity when compared with FL-treated tumors. These changes represent pitfalls in the diagnosis and grading of treated carcinomas. Nearly every treated adenocarcinoma of the prostate has neuroendocrine differentiation, showing increasing ChrA labeling with higher tumor stage. A significant correlation between tumor proliferation and neuroendocrine differentiation was noticed in this small cohort of patients. There was a high incidence of periprostatic venous thrombosis after EMP treatment.