Robert W. Veltri

EGFR-Mediated Beclin 1 Phosphorylation in Autophagy Suppression, Tumor Progression, and Tumor Chemoresistance

Cell surface growth factor receptors couple environmental cues to the regulation of cytoplasmic homeostatic processes, including autophagy, and aberrant activation of such receptors is a common feature of human malignancies. Here, we defined the molecular basis by which the epidermal growth factor receptor (EGFR) tyrosine kinase regulates autophagy. Active EGFR binds the autophagy protein Beclin 1, leading to its multisite tyrosine phosphorylation, enhanced binding to inhibitors, and decreased Beclin 1-associated VPS34 kinase activity. EGFR tyrosine kinase inhibitor (TKI) therapy disrupts Beclin 1 tyrosine phosphorylation and binding to its inhibitors and restores autophagy in non-small-cell lung carcinoma (NSCLC) cells with a TKI-sensitive EGFR mutation. In NSCLC tumor xenografts, the expression of a tyrosine phosphomimetic Beclin 1 mutant leads to reduced autophagy, enhanced tumor growth, tumor dedifferentiation, and resistance to TKI therapy. Thus, oncogenic receptor tyrosine kinases directly regulate the core autophagy machinery, which may contribute to tumor progression and chemoresistance.

Tumor angiogenesis correlates with progression after radical prostatectomy but not with pathologic stage in Gleason sum 5 to 7 adenocarcinoma of the prostate.

Prior studies have suggested that tumor angiogenesis (microvessel density [MVD]) may be of prognostic significance in patients with prostate carcinoma.

Neuroendocrine differentiation in prostate cancer: Enhanced prediction of progression after radical prostatectomy

It is controversial whether neuroendocrine (NE) differentiation in adenocarcinoma of the prostate is associated with more aggressive behavior. Most studies included patients with tumors of a wide range of grades and stages and an end point of disease-specific survival, a relatively insensitive marker of progression. The authors studied completely embedded radical prostatectomy specimens from 104 patients with clinically organ-confined carcinoma and no history of adjuvant or neoadjuvant therapy. Progression was marked by a serum prostate-specific antigen (PSA) concentration greater than or equal to 0.2 ng/mL. Seventy-six men did not progress, with a mean follow-up period of 8.0 years (range = 7 to 10 years). Forty-eight men progressed at a mean time after surgery of 3.6 years (range = 1 to 8 years). Twenty-one percent of the tumors were organ confined: 79% had capsular penetration. Seminal vesicles and lymph nodes were negative in all cases. A representative section through the main tumor mass was stained for chromogranin A. Reactive neoplastic cells were counted subjectively as well as individually enumerated. Gleason grade, pathological stage, and degree of NE differentiation all correlated with progression. Only grade and extent of NE differentiation predicted progression in a multivariate analysis. NE differentiation did not correlate with stage or grade. Extent of NE differentiation separated patients (59 cases) with tumors of Gleason sum less than or equal to 6 into groups with high and low risks for progression (P < .008) independent of Gleason sum. Extent of NE differentiation provides prognostic information in addition to that provided by grade in cases of early prostate cancer treated by radical prostatectomy.

Interleukin-8 serum levels in patients with benign prostatic hyperplasia and prostate cancer

OBJECTIVES Using arbitrarily primed polymerase chain reaction (AP-PCR) ribonucleic acid (RNA) fingerprinting, we discovered a messenger RNA (mRNA) that encoded the cytokine interleukin-8 (IL-8) that was up-regulated in the peripheral blood leukocytes (PBLs) of patients with metastatic prostate cancer (CaP) compared with similar cells from healthy individuals. We compared the total prostate-specific antigen (PSA) levels, the free/total (f/t) PSA ratios, and the immunoreactive IL-8 serum concentrations in patients with either biopsy-confirmed benign prostatic hyperplasia (BPH) or CaP. METHODS The sera from 35 apparently healthy normal volunteers and 146 patients with biopsy-confirmed BPH and CaP obtained from two academic centers were retrospectively examined to determine the serum levels of IL-8, total PSA (tPSA), and the f/t PSA ratio. Logistic regression and trend analysis statistical methods were used to assess the results. RESULTS Normals (n = 35), BPH patients (n = 53), patients with clinical Stages A to C CaP (n = 81), and patients with metastatic CaP (n = 1 2) had mean levels of IL-8 of 6.8, 6.5, 15.6, and 27.8 pg/mL, respectively. The IL-8 serum concentrations correlated with increasing CaP stage and also differentiated BPH from clinical Stages A, B, C, or D CaP better than tPSA and performed similarly to the f/t PSA ratio. The combination of the IL-8 levels and f/t PSA ratios using multivariate logistic regression analysis distinguished BPH from Stages A, B, C, or D CaP or only Stages A and B with a receiver operating characteristic area under the curve of 89.8% and 87.5%, respectively (P <0.0001). CONCLUSIONS The IL-8 serum concentration in our clinically well-defined patient sample was independent of the f/t PSA ratio as a predictor of CaP. When test samples are controlled for extraneous clinical origin of inflammation or infection, the combination of the IL-8 and f/t PSA assay results may offer an improved approach for distinguishing BPH from CaP.

Viral and epidemiologic studies of idiopathic sudden hearing loss.

The relationship between viral seroconversions and idiopathic sudden hearing loss (ISHL) is studied. Compared with our control group, the incidence of viral seroconversions is greater among ISHL patients, both for single and multiple viral infections. There was a significantly greater number of patients with seroconversions to mumps, rubeola, varicella-zoster, cytomegalovirus, and influenza B. We were unable to find a relationship between viral seroconversion and type or degree of hearing loss, vertigo, or chance for recovery. The incidences of viral conversion and sudden hearing loss track one another closely, suggesting that viral infection is a major cause of ISHL. During this 3-year study in Boston, ISHL was most prevalent in the spring.

Immunohistochemical differentiation of high-grade prostate carcinoma from urothelial carcinoma.

The histologic distinction between high-grade prostate cancer and infiltrating high-grade urothelial cancer may be difficult, and has significant implications because each disease may be treated very differently (ie, hormone therapy for prostate cancer and chemotherapy for urothelial cancer). Immunohistochemistry of novel and established prostatic and urothelial markers using tissue microarrays (TMAs) were studied. Prostatic markers studied included: prostate-specific antigen (PSA), prostein (P501s), prostate-specific membrane antigen (PSMA), NKX3.1 (an androgen-related tumor suppressor gene), and proPSA (pPSA) (precursor form of PSA). “Urothelial markers” included high molecular weight cytokeratin (HMWCK), p63, thrombomodulin, and S100P (placental S100). TMAs contained 38 poorly differentiated prostate cancers [Gleason score 8 (n=2), Gleason score 9 (n=18), Gleason score 10 (n=18)] and 35 high-grade invasive urothelial carcinomas from radical prostatectomy and cystectomy specimens, respectively. Each case had 2 to 8 tissue spots (0.6-mm diameter). If all spots for a case showed negative staining, the case was called negative. The sensitivities for labeling prostate cancers were PSA (97.4%), P501S (100%), PSMA (92.1%), NKX3.1 (94.7%), and pPSA (94.7%). Because of PSAs high sensitivity on the TMA, we chose 41 additional poorly differentiated primary (N=36) and metastatic (N=5) prostate carcinomas which showed variable PSA staining at the time of diagnosis and performed immunohistochemistry on routine tissue sections. Compared to PSA, which on average showed 18.8% of cells with moderate to strong positivity, cases stained for P501S, PSMA, and NKX3.1 had on average 42.5%, 53.7%, 52.9% immunoreactivity, respectively. All prostatic markers showed excellent specificity. HMWCK, p63, thrombomodulin, and S100P showed lower sensitivities in labeling high-grade invasive urothelial cancer in the TMAs with 91.4%, 82.9%, 68.6%, and 71.4% staining, respectively. These urothelial markers were relatively specific with only a few prostate cancers showing scattered (≤2%) weak-moderate positive cells. In summary, PSA can be used as the first screening marker for differentiating high-grade prostate adenocarcinoma from high-grade urothelial carcinoma. Immunohistochemistry for P501S, PSMA, NKX3.1, and pPSA are useful when high-grade prostate cancer is suspected based on the morphology or clinical findings, yet shows negative or equivocal PSA staining. HMWCK and p63 are superior to the novel markers thrombomodulin and S100P.

Gleason Score 6 Adenocarcinoma: Should It Be Labeled As Cancer?

Overtreatment of low-grade prostate cancer (Gleason score ≤ 6) is a recognized problem today, with systematic prostate gland sampling triggered by prostate-specific antigen (PSA) measurements.1 The extent to which overtreatment is caused by fear of death resulting from cancer, fear of litigation from undertreatment, and misaligned incentives that reimburse more for treating rather than monitoring when appropriate is not known. Nevertheless, fear of death resulting from cancer likely plays some role, and removing the label “cancer” could reduce unnecessary treatment of low-grade disease.2,3 On the other hand, undertreatment of prostate cancer and a missed opportunity for cure in those who could benefit is a real risk of relabeling a cancer as noncancer. We have decided on an alternative modification of the Gleason scoring system and herein present the arguments for and against removing the label of cancer from Gleason 6 tumors. We believe that our alternative approach may help: one, ensure that patients receive the proper counseling/treatment; two, reduce the risk of overtreatment and its associated harms; and three, improve shared decision making.

EFFECTS OF A SAW PALMETTO HERBAL BLEND IN MEN WITH SYMPTOMATIC BENIGN PROSTATIC HYPERPLASIA

PURPOSE We tested the effects of a saw palmetto herbal blend in men with symptomatic benign prostatic hyperplasia (BPH) via a randomized, placebo controlled trial. MATERIALS AND METHODS We randomized 44 men 45 to 80 years old with symptomatic BPH into a trial of a saw palmetto herbal blend versus placebo. End points included routine clinical measures (symptom score, uroflowmetry and post-void residual urine volume), blood chemistry studies (prostate specific antigen, sex hormones and multiphasic analysis), prostate volumetrics by magnetic resonance imaging, and prostate biopsy for zonal tissue morphometry and semiquantitative histology studies. RESULTS Saw palmetto herbal blend and placebo groups had improved clinical parameters with a slight advantage in the saw palmetto group (not statistically significant). Neither prostate specific antigen nor prostate volume changed from baseline. Prostate epithelial contraction was noted, especially in the transition zone, where percent epithelium decreased from 17.8% at baseline to 10.7% after 6 months of saw palmetto herbal blend (p <0.01). Histological studies showed that the percent of atrophic glands increased from 25. 2% to 40.9% after treatment with saw palmetto herbal blend (p <0.01). The mechanism of action appeared to be nonhormonal but it was not identified by tissue studies of apoptosis, cellular proliferation, angiogenesis, growth factors or androgen receptor expression. We noted no adverse effects of saw palmetto herbal blend. When the study was no longer blinded, 41 men elected to continue therapy in an open label extension. CONCLUSIONS Saw palmetto herbal blend appears to be a safe, highly desirable option for men with moderately symptomatic BPH. The secondary outcome measures of clinical effect in our study were only slightly better for saw palmetto herbal blend than placebo (not statistically significant). However, saw palmetto herbal blend therapy was associated with epithelial contraction, especially in the transition zone (p <0.01), indicating a possible mechanism of action underlying the clinical significance detected in other studies.

Update on the Appropriate Staging Evaluation for Newly Diagnosed Prostate Cancer

PURPOSE Prostate cancer clinical staging methods and decision support tools were reviewed to assess their accuracy to predict pathological staging results and determine what comprises an appropriate clinical staging evaluation. MATERIALS AND METHODS The MEDLINE data base was searched and 238 abstracts were obtained. Data were extracted from 142 articles that evaluated the preoperative accuracy of digital rectal examination, prostate specific antigen, prostatic acid phosphatase, systematic biopsy parameters (including Gleason scoring), seminal vesicle biopsy, various imaging studies and pelvic lymphadenectomy versus pathological staging results. The sensitivity, specificity and accuracy rates were calculated and tabulated from the reported data on each method or decision support tools for organ confined, nonorgan confined and lymph node metastatic tumor. RESULTS Decision support tools based on logistic regression analysis, which combine several statistically independent staging parameters, had greater accuracy than any single clinical staging method alone. The most accurate decision support tools for clinical staging combined digital rectal examination (T stage), systematic biopsy parameters (including Gleason scoring) and prostate specific antigen. CONCLUSIONS The components that comprise the most accurate decision support tools for clinical staging represent an appropriate staging evaluation for the newly diagnosed prostate cancer patient in 1997. Limited use of radiographic imaging and seminal vesicle biopsy may be indicated in select patients to detect bone metastases, and plan pelvic lymphadenectomy and surgical therapy.

Observations on pathology trends in 62,537 prostate biopsies obtained from urology private practices in the United States

OBJECTIVES To evaluate pathology trends of 62,537 first-time prostate needle-core biopsies submitted by office-based urologists, processed at a single pathology laboratory. METHODS Prostate biopsy cases obtained over a 2-year period were assessed. Patient information included age, digital rectal examination (DRE) status, and prostate-specific antigen (PSA) serum levels. Biopsy pathology results included the number of tissue samples per case, Gleason score, presence of Gleason grades 4 or 5, percent of biopsy length with evidence of cancer, number of samples with cancer per biopsy, and determination of DNA ploidy status using microspectrophotometry. RESULTS Adenocarcinoma, suspicious lesions, and isolated high-grade prostatic intraepithelial neoplasia (PIN) were diagnosed in 38.3%, 2.9%, and 4.1% of the biopsies, respectively. For each serum PSA and age range assessed, the positive biopsy rate and incidence of critical pathologic features increased consistently. The average percentage of biopsy length with evidence of tumor, the percentage of cases with Gleason grades 4 or 5, and the percentage of cases with an abnormal DNA ploidy all decreased significantly over the 2-year period (P <0.01). CONCLUSIONS The number of tissue cores and anatomic sites (locations) being sampled per biopsy are increasing. The tumor size detected and percentage of cases with Gleason grades 4 and 5 are decreasing. There has been a slight increase in the number of biopsies performed on men younger than 60 years of age and a slight decrease in biopsies performed on men older than 70 years of age. The decline in meaningful pathologic features observed in biopsies over time may be clinically relevant to improved disease management.