Frequency of apoptotic bodies positively correlates with Gleason grade in prostate cancer

Advances in biological functions and applications of apoptotic vesicles

BACKGROUND

Apoptotic vesicles are extracellular vesicles generated by apoptotic cells that were previously regarded as containing waste or harmful substances but are now thought to play an important role in signal transduction and homeostasis regulation.

METHODS

In the present review, we reviewed many articles published over the past decades on the subtypes and formation of apoptotic vesicles and the existing applications of these vesicles.

RESULTS

Apoptotic bodies were once regarded as vesicles released by apoptotic cells, however, apoptotic vesicles are now regarded to include apoptotic bodies, apoptotic microvesicles and apoptotic exosomes, which exhibit variation in terms of biogenesis, sizes and properties. Applications of apoptotic vesicles were first reported long ago, but such reports have been rarer than those of other extracellular vesicles. At present, apoptotic vesicles have been utilized mainly in four aspects, including in direct therapeutic applications, in their engineering as carriers, in their construction as vaccines and in their utilization in diagnosis.

CONCLUSION

Building on a deeper understanding of their composition and characteristics, some studies have utilized apoptotic vesicles to treat diseases in more novel ways. However, their limitations for clinical translation, such as heterogeneity, have also emerged. In general, apoptotic vesicles have great application potential, but there are still many barriers to overcome in their investigation. Video Abstract.

Apoptotic bodies: bioactive treasure left behind by the dying cells with robust diagnostic and therapeutic application potentials

Apoptosis, a form of programmed cell death, is essential for growth and tissue homeostasis. Apoptotic bodies (ApoBDs) are a form of extracellular vesicles (EVs) released by dying cells in the last stage of apoptosis and were previously regarded as debris of dead cells. Recent studies unraveled that ApoBDs are not cell debris but the bioactive treasure left behind by the dying cells with an important role in intercellular communications related to human health and various diseases. Defective clearance of ApoBDs and infected-cells-derived ApoBDs are possible etiology of some diseases. Therefore, it is necessary to explore the function and mechanism of the action of ApoBDs in different physiological and pathological conditions. Recent advances in ApoBDs have elucidated the immunomodulatory, virus removal, vascular protection, tissue regenerative, and disease diagnostic potential of ApoBDs. Moreover, ApoBDs can be used as drug carriers enhancing drug stability, cellular uptake, and targeted therapy efficacy. These reports from the literature indicate that ApoBDs hold promising potential for diagnosis, prognosis, and treatment of various diseases, including cancer, systemic inflammatory diseases, cardiovascular diseases, and tissue regeneration. This review summarizes the recent advances in ApoBDs-related research and discusses the role of ApoBDs in health and diseases as well as the challenges and prospects of ApoBDs-based diagnostic and therapeutic applications.

Proteomic profiling in extracellular vesicles for cancer detection and monitoring

Extracellular vesicles (EVs) are nanometer-size lipid vesicles released by cells, which play essential biological functions in intercellular communication. Increasing evidence indicates that EVs participate in cancer development, including invasion, migration, metastasis, and cancer immune modulation. One of the key mechanisms is that EVs affect different cells in the tumor microenvironment through surface-anchor proteins and protein cargos. Moreover, proteins specifically expressed in tumor-derived EVs can be applied in cancer diagnosis and monitoring. Besides, the EV proteome also helps to understand drug resistance in cancers and to guide clinical medication. With the development of mass spectrometry and array-based multi-protein detection, the research of EV proteomics has entered a new era. The high-throughput parallel proteomic profiling based on these new platforms allows us to study the impact of EV proteome on cancer progression more comprehensively and to describe the proteomic landscape in cancers with more details. In this article, we review the role and function of different types of EVs in cancer progression. More importantly, we summarize the proteomic profiling of EVs based on different methods and the application of EV proteome in cancer detection and monitoring.

Morphological and functional alterations of the prostate tissue during clinical progression in hormonally-naïve, hormonally-treated and castration-resistant patients with metastatic prostate cancer

Since commony used tools in oncological practice for the diagnosis of castration-resistent prostatic acinar adenocarcinoma are based on clinical criteria, such as castrate testosterone level, continuous rise in serum prostate-specific antigen, progression of preexisting disease or appearance of new metastases, it is important to identify reliable histopathological markers for the identification of this disease. Therefore, the aim of the present study was to determine the association between results from histological analysis, ultrastructural analysis and apoptosis in the prostate of patients with metastatic acinar prostatic adenocarcinoma (mPC). Patients were treated with androgen deprivation therapy (ADT), abiraterone acetate (Abi) therapy or received no treatment. Prostate tissue samples were divided into four groups as follows: i) Group 1, tissues from patients with benign prostatic hyperplasia (adenocarcinoma negative); ii) group 2, tissues from patients with metastatic hormone naïve prostate cancer; iii) group 3, tissues from patients with mPC treated with ADT; and iv) group 4, tissues from patients with metastatic castration-resistant prostate cancer treated with ADT and Abi. Immunohistochemical, terminal deoxynucleotidyl-transferase-mediated dUTP nick end labelling (TUNEL) and ultrastructural assays using light, fluorescence and transmission electron microscopy, respectively, were used to analyze prostate tissue samples. The results demonstrated that ADT and Abi therapy caused histological and ultrastructural changes in prostate tissues. In groups 3 and 4, benign and malignant tissues were affected by the hormonal therapy. Histologically, the malignant epithelium after ADT therapy in groups 3 and 4 presented with a loss of glandular architecture, nuclear and nucleolar shrinkage, chromatin condensation and cytoplasmic clearing. At the ultrastructural level, compact hypertrophic and hyperchromatic nuclei with numerous invaginations were observed in groups 2, 3 and 4. In addition, the incidence of abnormal mitochondria in malignant cells of these groups was high. Group 4 was characterized by the presence of malignant mesenchyme-like cells in the prostatic stroma, arranged in small groups surrounded by collagen fibrils. Furthermore, the cytoplasm of these cells contained filaments. A decrease in the number of apoptotic cells using TUNEL assays in the examined samples was observed with increasing disease progression. The findings from the present study suggest that the duration of treatment with ADT and progression of the disease were associated with apoptosis dysregulation.

Extracellular vesicles as emerging targets in cancer: Recent development from bench to bedside

Extracellular vesicles (EVs) have emerged as important players of cancer initiation and progression through cell-cell communication. They have been recognized as critical mediators of extracellular communications, which promote transformation, growth invasion, and drug-resistance of cancer cells. Interestingly, the secretion and uptake of EVs are regulated in a more controlled manner than previously anticipated. EVs are classified into three groups, (i) exosomes, (ii) microvesicles (MVs), and (iii) apoptotic bodies (ABs), based on their sizes and origins, and novel technologies to isolate and distinguish these EVs are evolving. The biologically functional molecules harbored in these EVs, including nucleic acids, lipids, and proteins, have been shown to induce key signaling pathways in both tumor and tumor microenvironment (TME) cells for exacerbating tumor development. While tumor cell-derived EVs are capable of reprogramming stromal cells to generate a proper tumor cell niche, stromal-derived EVs profoundly affect the growth, resistance, and stem cell properties of tumor cells. This review summarizes and discusses these reciprocal communications through EVs in different types of cancers. Further understanding of the pathophysiological roles of different EVs in tumor progression is expected to lead to the discovery of novel biomarkers in liquid biopsy and development of tumor specific therapeutics. This review will also discuss the translational aspects of EVs and therapeutic opportunities of utilizing EVs in different cancer types.

Apoptotic and Mitotic Index in Squamous Cell Carcinomas and Premalignant Lesions of the Uterine Cervix

The aim of this study was to determine the frequency of apoptotic and mitotic cells in different grades of premalignant lesions and in different stages of squamous cell carcinoma (SCC) of the uterine cervix. The apoptotic and mitotic indices (A! and MI) of 55 H&E-stained sections of cervical intraepithelial neoplasia (CIN) and 30 SCCs were evaluated in light microscopy by a morphometric method. Twenty, 16, and 19 of 55 CIN cases were classified in CIN I, CIN II, and CIN III group, respectively. No apoptosis was observed in the normal epithelium next to the dysplastic mucosa. There was no statistically significant difference between CIN I and CIN II as well as CIN II and CIN III groups in terms of apoptotic and mitotic cell counts. Mitotic cell counts were found significantly higher in CIN III group when compared with CIN I and CIN II groups together. There was no statistically significant difference in the apoptotic and mitotic cell counts between nonkeratinizing and keratinizing types of SCC. In the SCC group, apoptotic cell counts did not show significant difference between tumor stages. But mitotic counts were significantly higher in advanced stage tumors. The SCC group showed significantly higher mitotic and apoptotic cell counts when compared with preneoplastic lesions. This study suggests that apoptotic function is not altered during progressive stages of dysplastic change in cervical epithelium, while proliferation is triggered only in late stages of dysplasia. Both apoptosis and mitosis are markedly increased in progression to malignancy in cervix epithelium. Mitotic cell counts may be helpful in predicting the extent of the disease in SCC. Resistance of cell death by apoptosis after invasion may accelerate the net growth of the tumor resulting in advanced disease.

MS4A8B promotes cell proliferation in prostate cancer

BACKGROUND

Prostate cancer cells must maintain or achieve the further ability of proliferation during the progression. The molecular mechanisms, however, remain poorly understood. We identified a novel oncogene, termed membrane-spanning 4-domains, subfamily A, member 8B (MS4A8B), over-expressed in prostate cancer.

METHODS

We firstly detected MS4A8B mRNA in 13 types of paired human normal and cancer tissues by real-time polymerase chain reaction (RT-PCR). In 140 clinically localized prostate cancer samples from radical prostatectomy, immunohistochemical staining was performed to study MS4A8B and PCNA protein level as an index of proliferative activity, TUNEL staining as an index of apoptosis. As MS4A8B RNAi and cDNA transfection technologies were used, the effect of MS4A8B on cellular vitality was determined in vitro and in vivo.

RESULTS

MS4A8B mRNA was over-expressed specifically in prostate cancer. Positive ratios of MS4A8B protein expression were 1.94%, 5.92%, and 62.8% in benign, HPIN and prostate cancer, respectively. Moreover, MS4A8B was positively associated with Gleason score, the proliferation index. In vitro, MS4A8B knockdown resulted in G1 -S cell cycle arrest and descended vitality, MS4A8B over-expression with accelerated S phase entry, elevated vitality in prostate cancer cells. Moreover, it was also found that expression of MS4A8B led to changes of Cyclin D1 , Cyclin E1 and PCNA. LNCaP cells transfected with sh-MS4A8B lentivirus particles grew more slowly when subcutaneously injected into the flanks of nude mice.

CONCLUSIONS

We conclude that the expression of MS4A8B expression promotes cell proliferation and plays an important role in carcinogenesis and progression of prostate cancer.

Epigallocatechin-3-Gallate suppresses early stage, but not late stage prostate cancer in TRAMP mice: mechanisms of action

BACKGROUND

Prostate cancer (PCa) is the second leading cause of cancer-related death in men in the United States. Many men have implemented purported chemopreventive agents into their daily diet in an attempt to delay the early onset of a PCa. Green tea polyphenols, one such agent, has been shown to be chemopreventive in skin, breast, and prostate cancers. We hypothesized that Epigallocatechin-3-Gallate (EGCG), the major polyphenol found in green tea, will exert its chemopreventive effect in the prostate via regulation of sex steroid receptor, growth factor-signaling, and inflammatory pathways.

METHODS

Five-week-old male TRAMP (Transgenic Adenocarcinoma Mouse Prostate) offspring were fed AIN-76A diet and 0.06% EGCG in tap water. Animals were sacrificed at 28 weeks of age and the entire prostates were scored histopathologically. In addition, animals were sacrificed at 12 weeks of age and ventral (VP) and dorsolateral (DLP) prostates were removed for histopathological evaluation and immunoblot analyses or ELISA.

RESULTS

EGCG, inhibited early but not late stage PCa in the current study. In the VP, EGCG significantly reduced cell proliferation, induced apoptosis, and decreased androgen receptor (AR), insulin-like growth factor-1 (IGF-1), IGF-1 receptor (IGF-1R), phospho-extracellular signal-regulated kinases 1 and 2 (phospho-ERKs 1 and 2), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS).

CONCLUSIONS

The attenuation of the AR, the down-regulation of potent growth factor IGF-1, modulation of inflammation biomarkers, and decrease in the MAPK signaling may contribute to the reduction in cell proliferation and induction of apoptosis and hence provide a biochemical basis for EGCG suppressing PCa without toxicity.

Number and location of nucleoli and presence of apoptotic bodies in diagnostically challenging cases of prostate adenocarcinoma on needle biopsy

There is limited published data regarding the significance of the number or position of nucleoli and the presence of apoptotic bodies in diagnostically challenging cases of adenocarcinoma of the prostate on needle biopsy material. One hundred consecutive prostate cancers on needle biopsy were sent because of diagnostic difficulty to an expert in urological pathology, and the remaining normal benign prostatic glands on the same core were evaluated for the number and location of nucleoli and for the presence of mitotic figures and apoptotic bodies. The Gleason scores of the cases were 6 (86%), 7 (9%), and 8 to 10 (5%). For comparison, the same parameters were evaluated in mimickers of cancer on needle biopsy from other cases, including partial atrophy (n = 135), fully developed atrophy (n = 89), adenosis (n = 50), prostate glands with acute inflammation (n = 50), and high-grade prostatic intraepithelial neoplasia (n = 100). Findings were recorded under high dry magnification (x40) using hematoxylin and eosin-stained sections. Although the number and position of nucleoli did not discriminate between cancer and benign mimickers, mitotic figures and apoptotic bodies were more commonly seen in cancer. Apoptotic bodies in particular were seen fairly frequently (34%) in prostatic adenocarcinoma (also seen in 13% of high-grade prostatic intraepithelial neoplasia), yet rarely in benign mimickers on needle biopsy. Our findings indicate that the presence of apoptotic bodies should be added to the list of histological features that are helpful in the diagnosis of challenging cases of prostate cancer on needle biopsy.

Apoptosis in prostate cancer: bax correlation with stage

BACKGROUND

Dysregulation of apoptosis may contribute to the process of prostate tumorigenesis by reducing the rate of cell death. Bcl-2 and bax are important molecules involved in the regulation of apoptosis. The aim of the present study is to examine apoptosis and related regulatory molecular markers in a group of Iranian patients with prostate cancer.

METHODS

Paraffin-embedded tissues from 50 patients of prostate carcinoma were examined for the expression of bcl-2 antiapoptotic and bax proapoptotic markers and also proliferation marker, Ki-67, by immunohistochemistry. Detection of apoptotic cells was performed using TUNEL method. Correlation between apoptotic index, proliferation index and bcl-2 and bax expression with stage, pathological grade and Gleason score was determined.

RESULTS

Apoptosis was detected in 12% of prostate cancers. No correlation was observed between apoptosis and differentiation status of carcinoma. Bcl-2 expression was detected in 21 of samples. A significant correlation between bcl-2 expression and Ki-67 staining index (r = 0.349, P = 0.012) was observed. High bax protein expression was shown in our study. We found a significant correlation between bax expression and stage of carcinoma (r = 0.388, P = 0.031), but not with the apoptosis index, suggesting the presence of a non-functional bax protein or the role of other proapoptotic molecules.

CONCLUSION

The patients in the present study showed a different pattern of apoptosis positivity compared to other reports. Bax expression may be a useful marker for prognosis of prostate cancer.

Characterization of the autochthonous transgenic adenocarcinoma of the mouse prostate (TRAMP) as a model to study effects of castration therapy

BACKGROUND

In order to learn more about short- and long-term effects of castration therapy, relevant model systems for prostate cancer are required. In this study, we examined whether the transgenic adenocarcinoma of the mouse prostate (TRAMP) tumor response to castration in C57BL/6 mice mimics that seen in patients.

METHODS

Transgenic animals were examined before and 3 days after castration, at the ages of 17, 24, and 36 weeks. Moreover, 24-weeks old animals were castrated and followed for 6 months. Immunohistochemistry (IHC) and stereology were used to evaluate epithelial cell proliferation and death, blood vessel volume, androgen receptor (AR) expression, and transgenic expression of SV40 large T.

RESULTS

Cancer developed preferentially in the dorso-lateral prostate lobe. Tumor burden and incidence of metastases increased with age. The majority of tumors were well differentiated, while poorly differentiated, large tumors and macroscopic metastases developed in 8% of the animals. Well and moderately differentiated tumors responded to castration with cessation of proliferation and induction of apoptosis. Poorly differentiated tumors and metastases did not respond. Castration prevented local tumor growth for at least 6 months in 82% of the cases. Although, 45% of the treated animals developed wide-spread metastatic disease suggesting that castration may enhance growth of distant metastases.

CONCLUSIONS

The C57Bl/6 TRAMP tumor in several ways mimics how prostate cancer in patients responds to castration both in the short and long term, but some differences may also exist. This model can preferably be used to elucidate how this treatment works, and to test how it can be improved by additional therapies.

Ubiquitin is associated with the survival of ectopic stromal cells in endometriosis

Background

Endometriosis is a condition that affects women of reproductive age, where the glandular and/or stromal tissues from the eutopic endometrium implant in ectopic locations. It is well established that the survival of ectopic implants is due to lower levels of apoptosis, but no consensus exists as to which pathway/s this is mediated by. The ubiquitin protein shares a similar sequence homology to an anti-apoptotic protein called BAG-1 and is expressed in the normal endometrium. Currently, no studies have been conducted to determine ubiquitin expression and its possible anti-apoptotic effects in endometriosis.

Methods

Archived endometrial tissues from endometriosis patients and women undergoing laparoscopic diagnosis (controls) from January 2000 to July 2003 at Westmead Hospital were examined, where 14 cases of endometriosis and 55 controls were included in the study.

Results

Both the ubiquitin protein and apoptosis were expressed in both glandular and stromal cells throughout the menstrual cycle of the eutopic endometrium, in which ubiquitin exhibited a cyclic expression, reaching a peak in late proliferative phase. In contrast, ubiquitin was predominantly expressed in cells of stromal origin in endometriosis, was no longer regulated by a cyclic pattern and was associated with an aberrant level of cell survival.

Conclusions

For the first time, this study shows that ubiquitin is expressed in endometriotic cells and may contribute to a reduced sensitivity of ectopic endometrial tissue to apoptosis. These findings also suggest that stromal cells contribute differentially to the development of ectopic endometrial tissue.

Reduced Infiltration of Class A Scavenger Receptor Positive Antigen-Presenting Cells Is Associated with Prostate Cancer Progression

The class A macrophage scavenger receptor (SR-A) is expressed in antigen presenting cells and is involved in host immune responses. Germ-line mutation of this gene has been associated with increased risk of human prostate cancer. However, there is little known about its expression in normal or neoplastic human prostate tissues. Double immunofluorescent labeling with monoclonal antibodies to SR-A and specific macrophage and dendritic cell markers was used to identify cells expressing SR-A in human prostate tissues. SR-A immunohistochemical staining was performed on paraffin sections of normal prostate, prostatic intraepithelial neoplasia (PIN) lesions, and prostate cancers from radical prostatectomy specimens. SR-A was expressed in a subset of macrophages and dendritic cells that infiltrated prostatic tissues. The majority of SR-A-positive cells coexpressed CD68, and a relatively low percentage expressed S100 protein. The number of SR-A-positive cells was significantly increased in PIN as compared with normal prostatic tissue (P = 0.0176). In contrast, the number of SR-A-positive cells decreased with tumor progression. A lower SR-A-positive cell density was associated with higher clinical stage (rho = -0.26; P = 0.0234). Inverse associations were also found between SR-A density and positive lymph nodes (rho = -0.23; P = 0.0437), tumor size (rho = -0.31; P = 0.0100) and preoperative PSA levels (rho = -0.32; P = 0.0057). SR-A density is a significant predictor of disease-free survival after surgery univariately (P = 0.0003), as well as multivariately, adjusted for known clinical and pathological markers including preoperative prostate-specific antigen, clinical stage, Gleason score, surgical margin, extraprostatic extension, and seminal vesicle invasion, as well as lymph node metastasis (P = 0.0021). The preferential accumulation of SR-A-positive cells in PIN suggests a role for SR-A in the APC response to early malignancy. A reduction in the number of SR-A-positive cells demarcates tumor progression as indicated by clinical and pathological correlations. Our results additionally indicate that systematic measurement of SR-A density is a strong prognostic marker for clinical outcome after surgery.

Apoptosis, Proliferation, and Expression of p53 and bcl-2 in Endocervical Glandular Intraepithelial Lesions and Invasive Endocervical Adenocarcinoma

We evaluated apoptosis, proliferation, and p53 and bcl-2 expression in a spectrum of intraepithelial and invasive endocervical glandular lesions currently recognized by the World Health Organization as adenocarcinoma in situ, lesions with atypia "less than adenocarcinoma in situ" (endocervical glandular dysplasia and endocervical glandular atypia), and invasive adenocarcinoma. Aside from nuclear atypia, increased mitotic activity and apoptosis are consistent and closely correlated morphologic features of endocervical adenocarcinoma in situ. Apoptotic bodies and mitotic figures were counted in 32 examples of normal endocervical glands, 35 of endocervical glandular atypia, 30 of endocervical glandular dysplasia, 34 of adenocarcinoma in situ, and 30 of invasive adenocarcinoma. These results were correlated with immunohistochemical staining for MIB1, bcl-2, and p53 performed on 20 examples of each. Mitotic counts, p53 expression, and bcl-2 expression all increased significantly and in proportion to the degree of atypia in the spectrum of endocervical lesions. Apoptotic body counts and MIB1 expression also increased significantly with increasing atypia, but showed higher levels in adenocarcinoma in situ than in invasive adenocarcinoma. Apoptosis correlates with proliferation as measured by mitotic counts and MIB1, and also with p53 and bcl-2 expression. Apoptosis appears to be an important mechanism in the pathogenesis of endocervical glandular lesions and may be useful as an aid in their evaluation and diagnosis.

Apoptosis resistance of neuroendocrine phenotypes in prostatic adenocarcinoma

BACKGROUND

Neuroendocrine (NE) differentiation has been implicated in prostate cancer progression and hormone therapy failure. It has been shown that prostate cancer cells with NE features lack proliferation activity in vitro and in vivo. The current study reports on the apoptotic status of NE phenotypes in human prostate cancer.

METHODS

Double-label techniques were used for simultaneous demonstration of the endocrine marker chromogranin A (ChrA) and DNA fragmentation assessed by the terminal transferase-mediated biotinylated 16-desoxy-uridine-tri-phosphate (bio-16-dUTP) nick-end-labeling (TUNEL) assay. The material included primary prostatic adenocarcinoma (n = 18), lymph node metastases (n = 5), bone metastases (n = 2), and recurrent lesions (n = 10) showing NE differentiation at the immunohistochemical level.

RESULTS

Irrespective of grades, stages, and the degree of NE differentiation, DNA fragmentation was restricted to exocrine (ChrA-negative) tumor cells and was undetectable in most of NE tumor cells expressing ChrA. At least 0.16% of ChrA-positive tumor cells revealed DNA fragmentation assessed by the TUNEL assay.

CONCLUSION

The present data suggest that the vast majority of prostate cancer cells with NE features escapes programmed cell death. This escape may contribute significantly to their drug resistance and their malignant potential.

Apoptotic bodies as a morphological feature in serous ovarian carcinoma: correlation with nuclear grade, Ki-67 and mitotic indices

This study evaluated the relation of apoptosis with mitotic activity, Ki-67 indices, and nuclear and architectural grades in serous ovarian carcinoma. Apoptotic body (ABI) and mitotic indices (MI) were obtained by examining hematoxylin and eosin-stained sections from 35 serous ovarian carcinomas for apoptotic bodies and mitotic figures. ABI and MI were reported as the number of apoptotic bodies, and mitotic figures and immunostaining for Ki-67, respectively, as positive cells in 1000 cells. Nuclear grade was determined as grade 1 [n = 11], grade 2 [n = 13], and grade 3 [n = 11] according to recently defined criteria. There was a significant correlation between Ki-67 indices and ABI (p < 0.0001), Ki-67 and MI (p < 0.0001), as well as between MI and ABI (p < 0.0001). ABI increased with nuclear grade (p < 0.0001) and the type of the histological differentiation pattern (from glandular to papillary and solid architectural patterns) (p < 0.0001). Apoptosis, quantitated by ABI, is positively correlated with proliferation, thereby constituting a factor in the regulation of tumor growth of serous ovarian carcinomas. The positive correlation between ABI and increasing nuclear grade, mitotic activity, and architectural growth pattern may indicate that apoptotic bodies are another variable for grading serous ovarian carcinomas.

Proliferation, apoptosis, and intratumoral vascularity in multiple myeloma: correlation with the clinical stage and cytological grade

AIMS

Abnormalities involving proliferation, apoptosis, and angiogenesis are important in tumorigenesis. The purpose of this study was to examine these three biological processes, and their relation with the clinical stage and cytological grade in multiple myeloma (MM).

METHODS

Fifty four newly diagnosed patients with MM were studied by immunohistochemistry using bone marrow clot sections. Proliferation and apoptosis were evaluated for the proportion of MM cells (indicated by morphology and CD138 reactivity) positive for the Ki67 antigen and single stranded DNA (ssDNA), respectively. Angiogenesis was evaluated by measuring the intratumoral microvessel density (IMVD) and by assessing the immunoreactivity of vascular endothelial growth factor (VEGF).

RESULTS

There were 30 men and 24 women (median age, 65 years; range, 37-84). At initial presentation, 15 (28%) were in Durie stage I, 15 (28%) in stage II, and 24 (44%) in stage III. Advanced clinical stage correlated with high cytological grade (p < 0.03). The medians for Ki67, ssDNA, and IMVD were 4.4% (range, 0-15%), 0.2% (range, 0-2.8%), and 15.5 (range, 0-63), respectively. Among these three continuous parameters, the only significant correlation was that between Ki67 and IMVD (p < 0.0001). Both Ki67 and IMVD also correlated with the clinical stage, cytological grade, and VEGF positivity (p <0.05). No correlation was found between ssDNA and all of the other parameters.

CONCLUSIONS

These data suggest that proliferation is associated with angiogenesis in MM. Furthermore, proliferation and angiogenesis, but not apoptosis, may be important in disease progression. Lastly, increased production of VEGF may be one of the contributing factors to the increase in intratumoral vascularity seen in advanced MM.

Tumour grade, proliferation, apoptosis, microvessel density, p53, and bcl-2 in prostate cancers: differences between tumours located in the transition zone and in the peripheral zone

OBJECTIVES

Transition zone (TZ) carcinomas of the prostate are thought to have less malignant potential than tumours that arise in the peripheral zone (PZ). It is unclear, however, whether this can be put down to anatomical reasons alone, or if there are further differences between tumours of both zones.

METHODS

We examined Gleason scores, proliferation and apoptosis rates, microvessel density (MVD), p53 expression and bcl-2 expression in 76 paraffin-embedded radical prostatectomy specimens, containing 54 tumour foci in the TZ and 58 tumour foci in the PZ, matched for volume. The terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labelling (TUNEL) method was applied to detect apoptotic cells. Proliferation, MVD, p53, and bcl-2 were investigated by immunohistochemistry.

RESULTS

There were significant differences between TZ tumours and PZ tumours in terms of the median Gleason scores (5 versus 7; P < 0.0001), the proliferation rate (3.2% versus 5.2%; P = 0.0003), and the MVD (68.5 versus 104; P = 0.0002), but the median apoptosis rate was quite similar (0.8% versus 0.9%). The p53 and bcl-2 expression were more frequent in PZ cancers as compared to TZ carcinomas (11% versus 2% and 27% versus 6%, respectively).

CONCLUSION

There is evidence for lower Gleason scores as well as lower expression of markers related to tumour growth in TZ carcinomas of the prostate, which might contribute to a less malignant clinical behaviour as compared to PZ cancers.

Apoptotic cell death and Smad4 expression in transitional cell carcinoma of the renal pelvis and ureter

PURPOSE

To investigate the frequency of apoptosis and the expression of Smad4 protein as well as their roles in transitional cell carcinoma (TCC) of the renal pelvis and ureter.

METHODS

Apoptosis was detected by using terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) technique in 34 formalin-fixed and paraffin-embedded specimens of renal pelvic and ureteral TCC. The expression of Smad4 was immunohistochemically studied.

RESULTS

The incidence of apoptosis ranged from 1.10 to 3.75% with a median of 2.50% in TCC of the renal pelvis and ureter. The incidence of apoptosis was noted to be closely related to histologic grade but not to pathologic stage of the cancer. The expression of Smad4 was detected in six of 34 cases (17.6%). Regarding subcellular distribution, Smad4 protein was localized both in cytoplasm and nucleus of the cancer cells. In comparing the incidence of apoptosis with the expression of Smad4, no significant associations were seen between them. The expression of Smad4 was not related to the tumor grade nor stage of the cancer.

CONCLUSIONS

The present study demonstrated close association of the incidence of apoptosis with the tumor grade of TCC of the renal pelvis and ureter. Significance of Smad4 expression was not noted in the study. It suggests that apoptotic cell death may play an important role in the tumor progression of renal pelvic and ureteral TCC.

Regulation of apoptosis in prostatic disease

BACKGROUND

Recent studies suggest that aberrant regulation of apoptosis, including acquired apoptosis resistance, contributes to perturbations in cell growth that, in part, underlie the development of benign prostatic hyperplasia (BPH) and prostate cancer. Importantly, apoptosis resistance can enhance the malignant properties of prostate cancer cells, contributing to their widespread metastatic activities. Since apoptosis resistance likely contributes to benign and malignant prostate disease, the promotion of apoptosis represents a reasonable therapeutic objective.

METHODS

This brief review focuses on the role of apoptosis in prostatic disease and discusses potential intervention points for novel therapeutics.

CONCLUSIONS

Novel therapies for prostatic disease, including gene therapy and biological therapy that involve apoptosis as a mechanism of action, are being developed and tested. Ultimately, the identification of proapoptotic and antiapoptotic genes and the pathways through which they operate will serve to provide more rational approaches for further development of more efficacious therapeutic strategies for benign and malignant prostatic disease.

Caspase-3/CPP32 immunoreactivity and its correlation with frequency of apoptotic bodies in human prostatic carcinomas and benign nodular hyperplasias

AIMS

Apoptosis is mediated by apoptosis-specific genes, certain oncogenes and tumour suppressor genes. Caspase-3, a group of cystein proteases, is involved in the induction of apoptosis and has been considered to correlate with apoptosis. The aim of this study was to determine whether caspase-3 is expressed in prostatic carcinoma and benign prostatic hyperplasia, and correlated with the apoptosis.

METHODS AND RESULTS

We studied the apoptotic index and caspase-3 immunoreactivity in 40 cases of benign nodular hyperplasia (BPH) and 40 cases of prostate carcinoma (PCA) by in-situ labelling and immunohistochemistry. The mean number of apoptotic bodies in cases with BPH was not significantly different from cases with PCA I (Gleason score 2-4), but samples from patients with PCA II (Gleason score 5-7) and PCA III (Gleason score 8-10) showed a significantly higher apoptotic number than cases with BPH. Positive staining for caspase-3 was seen in 42.5% (17/40) of the BPH, and 27.5% (11/40) of the PCA: PCA I was 41.7% (5/12), PCA II 14.3% (2/14) and PCA III was 28.6% (4/14).

CONCLUSIONS

Based on our results, the number of apoptotic bodies was not correlated with the caspase-3 expression and there was no relationship between caspase-3 expression and Gleason score. However, the number of apoptotic bodies was significantly higher in cases with intermediate (Gleason score 5-7) and high-grade (Gleason score 8-10) PCAs than cases with BPH and low-grade PCAs (Gleason score 2-4).

Mouse prostate reconstitution model system: A series of in vivo and in vitro models for benign and malignant prostatic disease

BACKGROUND

An elucidation of the complex, morphological and molecular changes that underlie benign and malignant prostatic disease will likely lead to improved methods of diagnosis and therapy for those disorders. To identify and understand the interrelation of the phenotypic and genetic changes inherent in these important diseases requires the development and use of in vivo and in vitro models that closely mimic specific aspects of the disease process. Once the suspected molecular underpinnings of prostatic disease are uncovered, in vivo and in vitro models will be required for further testing of the functional significance of specific genetic alterations as they are identified. In addition models of prostatic disease are necessary to evaluate novel therapeutic approaches.

METHODS

The mouse prostate reconstitution (MPR) model system was developed more than a decade ago with these specific needs in mind. Over the years, specific modifications of the MPR model have demonstrated its versatility and applicability for the study of benign and malignant prostatic disease, including metastatic progression.

RESULTS

We discuss various modifications of the MPR model system made for its application to specific aspects of prostatic disease; the clinically relevant information that has been gleaned thus far from the use of this model system; and advances on the horizon for the expansion of its role in prostate research.

CONCLUSIONS

The MPR model system has contributed substantially to the understanding and treatment of benign and malignant prostatic diseases. Additional modifications in this series of in vivo and in vitro models will likely lead to further advances.

Apoptosis in cervical squamous carcinoma: predictive value for survival following radiotherapy

BACKGROUND

Apoptosis, or programmed cell death, can be induced by radiotherapy. The extent of apoptosis in a tumour before treatment may have important implications for response to radiotherapy and long term survival.

AIM

To examine the extent of apoptosis in tumour tissue from patients with squamous carcinoma of the cervix before radiotherapy, and to correlate this with response to treatment and prognosis.

METHODS

The percentage of apoptotic cells was assessed in 146 carcinomas of the cervix from patients scheduled to receive radiotherapy. The CAS 200 static image analysis system was used to count the number of tumour nuclei per high power field, while the numbers of apoptotic cells in the same field were visualised simultaneously on the image analyser and recorded manually.

RESULTS

The median apoptotic level was 0.73%. Patients were divided into two groups around the median. There was no statistically significant difference in outcome between the two groups as determined by long term survival following radiotherapy.

CONCLUSIONS

The CAS 200 static image analyser system can be used to assist in the rapid semiautomated assessment of apoptosis in conventionally prepared tissue. The results suggest that the apoptotic state of a tumour before treatment is of no value in predicting response to radiotherapy and subsequent prognosis. Tumour stage, size, and BrdU labelling index, as a measure of proliferation rate, remain the most important prognostic factors in terms of predicting local tumour control.

Apoptosis and p53 in inverting papilloma of the sinonasal tract

The objective of this study was to identify apoptotic bodies and p53 positivity in inverting papilloma lesions to study these two as biomarkers in premalignant lesions. Archival specimens of 15 patients with inverting papilloma between the years 1992 and 1995 were retrieved. In situ end labeling technique was used to identify apoptotic bodies. Immunohistochemistry was used to detect p53 in the same specimens. The clinical course was evaluated conducting a retrospective chart review in these patients. Compared to normal epithelium, inverting papilloma lesions had a greater proportion of apoptotic bodies, which was nearly statistically significant (average 0.506/100 cells for inverting papilloma compared with 0.1/100 cells for the normal surrounding tissue). Four cases of inverting papilloma were p53 positive. There was, however, no association between p53 positive staining and the apoptotic rate. The minimum follow-up for patients was 2 years. All had a uniformly good clinical outcome with only one patient who was p53 positive showing concurrent squamous cell carcinoma. We concluded that inverting papilloma contained a higher average number of apoptotic bodies compared with normal surrounding sinonasal tissue. This showed a trend toward a positive between the apoptotic rate and premalignancy, suggesting both increased cellular proliferation and increased cell death may occur in such lesions. In this study p53 did not show a positive association with the apoptotic rate, suggesting that p53 may not be directly involved in the apoptotic regulatory pathway in inverting papillomas.

Prognostic significance of apoptotic index in completely resected non-small-cell lung cancer

PURPOSE

To evaluate the significance of apoptotic index (AI) as a prognostic factor after surgery for non-small-cell lung cancer (NSCLC).

PATIENTS AND METHODS

A total of 236 patients who underwent surgery for previously untreated pathologic stage I to IIIa NSCLC between 1985 and 1990 were reviewed. AI was defined as the number of apoptotic cells, detected by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling, per 1,000 tumor cells. Proliferative index (PI) and aberrant p53 expression were also evaluated immunohistochemically.

RESULTS

The 5-year survival rate for the lowest-AI group (AI < 5.0) was 74.7%; those for the lower-AI group (5.0 < or = AI < 11.0) and the higher-AI group (11.0 < or = AI < 25.0) were 51.6% and 57.8%, respectively. These survival rates were significantly lower than that of the lowest-AI group (P =.021 and P =.043, respectively). The highest-AI group (25.0 < or = AI), however, showed the most favorable prognosis, with a 5-year survival rate of 83.2%. Multivariate analysis confirmed that a moderate AI (5.0 < or = AI < 11.0 or 11.0 < or = AI < 25.0) was a significant factor to predict poor prognosis. The PIs for the lowest-, the lower-, the higher-, and the highest-AI groups were 32.3%, 48.0%, 54.3%, and 50.7%, respectively. The lowest-AI group showed a favorable prognosis because of its low PI, whereas the lower- and the higher-AI groups had a poor prognosis caused by increased cancer-cell proliferation. The highest-AI group showed the most favorable prognosis because apoptotic cell death overcame cell proliferation. No significant correlation was observed between AI and aberrant p53 expression.

CONCLUSION

AI proved to be an independent prognostic factor in NSCLC.

Correlation between proliferation, apoptosis, and angiogenesis in prostate carcinoma and their relation to androgen ablation

BACKGROUND

Proliferation, apoptosis, and angiogenesis are essential for carcinogenesis. Little is known regarding the relation between proliferation, apoptosis, and angiogenesis in untreated prostate carcinoma as well as alterations associated with androgen ablation.

METHODS

Eighty patients who underwent radical prostatectomy for clinically localized prostate carcinoma were recruited for the study. The study population included 2 groups: 35 patients receiving 3-month neoadjuvant hormonal treatment using a combination of luteinizing hormone-releasing hormone analogue and the antiandrogen flutamide (NHT group) and 45 patients without prior treatment (non-NHT group). The authors measured the Ki-67 labeling index (Ki-67 LI) by MIB-1 immunohistochemistry, the apoptotic index (AI) by the terminal deoxynucleotidyl transferase-mediated dUTP biotin nick end labeling technique, and intratumoral microvessel density (IMVD) by CD31 immunohistochemistry on serial sections of formalin fixed, paraffin embedded tissues. Correlations among these parameters were examined in both groups.

RESULTS

A significant decrease in the Ki-67 LI coupled with a significant increase in AI was found in the NHT group compared with the non-NHT group, whereas IMVDs in both groups were not significantly different. AI was related to IMVD inversely in the non-NHT group (correlation coefficient [r] = -0.327; P = 0.03); in contrast, AI was related to IMVD positively in the non-NHT group (r = 0.579; P < 0.001). The Ki-67 LI was related to AI significantly in the non-NHT group but not in the NHT group. There was no correlation between Ki-67 LI and IMVD in either group.

CONCLUSIONS

Correlations between proliferation, apoptosis, and angiogenesis in prostate carcinoma are altered significantly in association with androgen ablation. The results indicate that spontaneous apoptosis is suppressed by neovascularization, whereas hormone-induced apoptosis is enhanced in hypervascular tumors.

Accelerated apoptosis and low bcl-2 expression associated with neuroendocrine differentiation predict shortened survival in operated large cell carcinoma of the lung

In order to test the hypothesis that increased apoptotic activity is connected with neuroendocrine differentiation and low differentiation degree in large cell carcinoma (LCLC) and is regulated by bcl-2 family proteins, we analysed the extent of apoptosis and tumor necrosis and their relation to the expression of bcl-2, bax, bak and mcl-1 in 35 LCLCs, of which 20 were classified as large cell neuroendocrine lung carcinomas (LCNEC) and 15 as large cell non-neuroendocrine lung carcinomas (LCNNEC). The extent of apoptosis was determined by detecting and counting the relative and absolute numbers of apoptotic cells and bodies using in situ 3 -end labelling of the apoptotic DNA. The extent and intensity of expression of the bcl-2, bax, bak and mcl-1 proteins were studied by immunohistochemistry. Also the relative volume density of necrosis was evaluated and correlated with the other parameters. Finally, all the parameters were evaluated as prognostic markers and correlated with data on the survival of the patients. Relatively high apoptotic indices were seen in both tumor types (average for both 2.53%, range 0.09 27.01%). Significantly higher bcl-2 and bak indices were detected more often in LCNECs than in LCNNECs. Immunohistochemically detected bax, bcl-2 and bak expression was independent of apoptotic index in both tumor types, while there was a statistically significant positive association between mcl-1 expression and apoptotic index in LCNNEC but not in LCNEC. There was a statistically significant association between high apoptotic index and shortened survival in LCLC. However, no association was found between tumor stage and apoptosis. The patients with LCNEC and low bcl-2 protein expression had a significantly shorter survival time than those with high bcl-2 indices. There was also a clear association between shortened survival and necrotic LCNNEC. LCLCs show relatively high apoptotic activity, which is associated with shortened survival. The expression of bcl-2, bak and mcl- 1 is associated with neuroendocrine differentiation in LCLC. Finally, our results support some previous reports suggesting that bcl-2 expression in combination with some other markers involved in apoptosis and/or proliferation may be of prognostic value in cases of lung carcinoma with neuroendocrine differentiation.

Expression of Bcl-2, Bax, and p53 in high-grade prostatic intraepithelial neoplasia and localized prostate cancer: relationship with apoptosis and proliferation

BACKGROUND

Apoptosis-regulating genes have been shown to be important in the biology of prostate cancer. The aim of this study was to examine and correlate the expression of the apoptosis-regulating genes bcl-2, bax, and p53 with the frequency of apoptosis and rate of proliferation in benign prostatic epithelium (BP), prostate cancer, and high-grade prostatic intraepithelial neoplasia (HGPIN), which is currently considered the most likely precursor of prostate cancer.

METHODS

Forty-four patients with histologically proven prostate cancer were investigated. All the men underwent radical prostatectomy. Immunohistochemistry was performed to assess expression of bcl-2, bax, and p53, and proliferation rate, as measured by the Ki-67 index. The frequency of apoptotic bodies was assessed by morphological criteria.

RESULTS

The apoptotic index (AI) was highest in prostate cancer, and was significantly greater in HGPIN compared to benign prostate. The Ki-67 index was greatest in cancer, intermediate in HGPIN, and lowest in BP. The AI was increased in areas of BP in patients treated with neoadjuvant androgen ablation. No change in AI was seen in treated cases of HGPIN or cancer. Accumulation of p53 protein was infrequent in prostate cancer (2/43: 4.6%), and was absent in HGPIN. Bcl-2 overexpression was present in 2.3% of cancers (1/43) and in 34.9% of cases of HGPIN (15/43). Bax expression was seen in all cases of cancer and HGPIN. There was no correlation between bcl-2 expression and the apoptotic and Ki-67 indices in HGPIN.

CONCLUSIONS

p53 and bcl-2 expression is infrequent in clinically organ confined prostate cancer. Bcl-2 expression is significantly higher in HGPIN than in both the associated prostate cancer and BP. The AI and Ki-67 index appeared intermediate in the putative precursor lesion HGPIN compared to prostate cancer and BP.

Correlation of proliferation indices, apoptosis, and related oncogene expression (bcl-2 and c-erbB-2) and p53 in proliferative, hyperplastic, and malignant endometrium

BACKGROUND

The various morphological groupings of endometrial pathology are often difficult to distinguish from each other. The endometrium is an actively proliferating tissue and there is an overlap in cell proliferation fraction (CPF) between benign proliferative endometrium (BPE) and endometrial carcinoma (EC). Apoptosis in benign cycling endometrium is related to the menstrual cycle. In this study we evaluated CPF, apoptosis, and oncogenes that relate to cell turnover (bcl-2, p53, and c-erbB-2) in the spectrum of endometrial pathology.

METHODS

We examined a total of 64 cases consisting of 10 cases of BPE, 18 cases of simple endometrial hyperplasia (SEH), 18 cases of complex hyperplasia (CEH; including eight cases with atypical hyperplasia), and 18 cases of EC, FIGO grade 1. CPF was measured by the mitotic index (MI) and by the percentage of Ki-67 positive nuclei (Ki-67 index). Apoptotic index (AI) was determined on hematoxylin and eosin sections.

RESULTS

MI was 2.48% in BPE, 0.65% in SEH, 0.6% in CEH, and 0.91% in EC (P < .00001). Ki-67 index was 38.44%, 16.4%, 23.25%, and 31.7% respectively (P < .00001). AI was 1.17%, 2.2%, 2.57%, and 3.31% respectively (P = .02). The AI/MI and AI/Ki-67 ratios were lowest in BPE and highest in SEH (P = .007). All cases of BPE, 84% of SEH cases, 77% of CEH cases, and 88% of EC cases displayed cytoplasmic and/or nuclear bcl-2 expression. Cytoplasmic bcl-2 expression increased from BPE to SEH, whereas it decreased in CEH and EC with emergence of only nuclear expression. Of the EC cases, 38.8% showed intense nuclear bcl-2 reactivity and a significantly higher Ki-67 index than cases with cytoplasmic expression (P = .01). No p53 or c-erbB-2 expression was seen in either BPE or EH. Of the EC cases, 50% were positive for p53 whereas 30% were positive for c-erbB-2. C-erbB-2-positive cases had a significantly higher Ki-67 index and AI than negative cases (P = .02). Cases of EC with p53 expression also had significantly higher AI (P = .01).

CONCLUSIONS

In actively proliferating tissues like endometrium, CPF does not correlate with progression to malignancy. In contrast, AI and derived AI/CPF ratios are better indicators of progression. The expression of p53, c-erbB-2, and nuclear bcl-2 in EC correlate with higher cell turnover indices (CPF and AI).

Telomeric DNA: marker for human prostate cancer development?

BACKGROUND

Telomeres that protect chromosomes at both ends are shortened with each somatic cell division through replication-dependent sequence loss at DNA termini. The chromosomes with shortened telomeres tend to become unstable, leading to cell death. Due largely to reactivation/upregulation of telomerase, a ribonucleoprotein that adds nucleotide sequences onto chromosome ends, cancer cells become immortal and neoplastically transformed.

METHODS

The purpose of the present study was to study three newly established human prostate cancer cell lines and three prostate-derived fibroblastic cell cultures at different passages for telomeric DNA signal intensity, telomeric restriction fragment length (TRFL), telomerase activity, and spontaneous apoptotic index.

RESULTS

Compared with the three fibroblastic cell cultures, the three new prostate cancer cell lines showed: 1) telomerase activity, 2) stronger telomeric signals, 3) relatively longer TRFLs, and 4) much lower apoptotic indices. On the other hand, three fibroblastic cell cultures showed: 1) no telomerase activity, 2) weaker telomeric signals, 3) shorter TRFLs (fibroblasts derived from surrounding tissue of prostate tumor showed intermediate TRFLs), and 4) comparatively higher apoptotic indices.

CONCLUSIONS

Based on these results, we conclude that telomeric DNA signal intensity, TRFL, and telomerase activity can be used to distinguish prostate cancer cells from adjacent fibroblasts.

Histopathologic review of prostate biopsies from patients referred to a comprehensive cancer center: correlation of pathologic findings, analysis of cost, and impact on treatment

BACKGROUND

Clinicians at the Fox Chase Cancer Center (FCCC) base prostate carcinoma treatment decisions regarding need to treat, field size, total dose, and adjuvant hormonal therapy on known prognostic factors including clinical stage, Gleason score (GS), perineural invasion (PNI), and pretreatment prostate specific antigen levels. The pathology of every patient is reviewed at FCCC to confirm a diagnosis of malignancy. The objective of this study was to define differences between pathologic reviews and their impact on treatment between outside institutions and FCCC.

METHODS

The authors reviewed 538 pathology reports of prostate biopsies performed at both outside pathology departments and FCCC on patients evaluated between January 1993 and December 1996. The outside pathology reviews represented 107 community hospitals, academic institutions, and private pathology laboratories. Patients who had received hormonal therapy, cryosurgery, or radical prostatectomy prior to prostate biopsy were excluded from analysis. Final FCCC pathology determinations were compared with pathology reports from outside institutions. Reports then were analyzed to determine whether differences in interpretation would have resulted in different treatment strategies. Differences in percentages according to institutional type were evaluated using the chi-square statistic. The cost was assessed and cost per change in treatment estimated.

RESULTS

The 538 pathology reviews identified a nearly 40% change in GS and a 13% change in > or =2 GS between the FCCC pathology review and 107 outside academic institutions. The results of this study showed that 22% of community hospitals, 10% of private laboratories, and 8% of academic institutions demonstrated at least 2 GS changes compared with the FCCC pathology review (p = 0.001). There was no significant difference observed between types of institutions in the incidence of PNI.

CONCLUSIONS

This analysis provides evidence of a significant difference in the pathologic reviews of prostate biopsies conducted at FCCC and outside pathology departments. There was a nearly 40% change in GS and a 13% change in > or =2 GS between the FCCC pathology review and 107 outside institutions. The second pathology review added approximately $104 per case for a total of $55,952 to review all 538 cases. Overall, the savings in health care dollars resulting from the second pathologic review totaled $12,997. This second review of outside pathology in prostate cancer appears to be justified based on the treatment changes and on cost.

Apoptosis and carcinogenesis: morphologic observations in the rat bladder treated with N-butyl-N-(4-hydroxybutyl)nitrosamine

BACKGROUND

We investigated the role of apoptosis in rat bladder carcinogenesis induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN).

METHODS

Apoptosis was detected in BBN-induced rat bladder lesions by routine hematoxylin and eosin (H&E) staining, terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end labeling (TUNEL), and transmission electron microscopic examinations.

RESULTS

After administration of BBN, various pathologic changes were observed in the rat bladder after intervals of between 4 and 28 weeks. Through a comparative study in serial sections, the incidence of apoptosis, detected by either routine H&E staining or TUNEL staining, displayed marked elevation in BBN-induced rat bladder lesions, as compared to that in the normal epithelium of the rat bladder, particularly in invasive transitional cell carcinoma. Apoptotic cells with different morphologic features were ultrastructurally demonstrated in a series of rat bladder lesions. Significant group differences in the incidence of apoptosis were seen among the BBN-induced lesions and the normal epithelium of the rat bladder, and among the invasive transitional cell carcinomas and other lesions, before the tumor cells were seen to invade the rat bladder.

CONCLUSION

Our data suggest that apoptosis may be closely related to carcinogenesis and tumor invasion of the rat bladder induced by BBN, and that the comparative study of serial sections, each stained by H&E and TUNEL, combined with electron microscopic observation, may provide the most reliable informations in semiquantitative assessment of apoptosis.

Investigation of p53, c-erbB-2, PCNA immunoreactivity, DNA content, AgNOR and apoptosis in bladder carcinoma as prognostic parameters

The association between known prognostic variables such as TNM stage, histological grade and mutant p53 tumor suppressor gene product, c-erbB-2 oncoprotein, DNA ploidy and cell kinetic data, including mitoses, PCNA expression, AgNOR scores and apoptosis, was investigated in 29 transitional cell carcinoma (TCC) cases. A positive correlation between the histologic grade and all the studied parameters, except for c-erbB-2 expression, and a positive correlation between the stage and histological grade, DNA ploidy, mitoses, apoptosis and p53 expression were found. The results of this study are in accordance with some of the previous studies, except for apoptosis which had been studied for the first time in TCCs. Although we found a statistically significant correlation between the apoptosis and both tumor stage and histological grade, the predictive value of apoptosis as an independent prognostic factor remains to be established in a larger series.

Apoptosis and cellular proliferation in human epidermal squamous cell neoplasia

We examined cell loss (apoptosis) and proliferation in a histopathological spectrum of epidermal squamous cell neoplasia, including 11 cases of solar keratosis (SK), 18 Bowen's diseases (BD) and 19 invasive squamous cell carcinomas (SCC). Apoptotic and proliferative cells were determined by terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-digoxigenin nick end labeling (TUNEL) and by the detection of nuclear antigen Ki-67, respectively. Few apoptotic cells were observed in normal epidermis, while TUNEL index (TI; percentage of TUNEL-positive cells) was highest for SCCs, followed by BDs and SKs, in the order given. Although the mean Ki-67 index did not differ between SCCs and BDs, both disease types showed a significantly higher index than the SKs. Of SCCs, both TI and Ki-67 index values were significantly higher in poorly than in well differentiated carcinomas. TI was significantly higher in SCCs without P53 immunohistochemical expression than in SCCs with P53 expression, while TI and Ki-67 indices did not correlate with P53 expression in the SKs and BDs. These results suggest that apoptosis reflects not only cell loss, but also proliferative activity in the epidermal neoplastic lesions.

Can apoptosis in benign proliferative lesions predict risk of cancer development?

The presence of benign proliferative lesions is a risk factor for the development of cancer. However, only a subset of individuals presenting with benign lesions goes on to develop cancer. It is a major challenge of cancer research to identify those individuals at increased risk for this neoplastic progression. It has been suggested that individuals with inherent genomic instability may have a predisposition for cancer development. The hypothesis is presented that this genetic instability could be quantified through the analysis of apoptosis in biopsies of benign lesions. It is further conjectured that genetic damage-dependent apoptosis might serve as a prognostic indicator to identify individuals at increased risk for cancer.

Incidence of apoptosis and metallothionein expression in renal cell carcinoma

OBJECTIVE

To investigate the frequency of apoptosis and expression of metallothionein (MT) protein and to clarify their roles in renal cell carcinoma (RCC).

MATERIALS AND METHODS

Apoptosis was detected by using the terminal deoxynucleotidyl transferase (TdT)-mediated dUTP-biotin nick-end labelling (TUNEL) technique in 70 formalin-fixed and paraffin-embedded RCC specimens. The expression of MT was determined immunohistochemically.

RESULTS

The incidence of apoptosis was significantly higher in grade 2 and 3 RCC than in grade 1. There were no significant differences amongst the other categories of RCC when grouped by tumour stage, cell type and growth pattern. The expression of MT was detected in 23 of 70 (33%) RCCs. Subcellularly. MT was localized in the cytoplasm, nucleus and cell membrane of RCC. Statistical analysis showed a close association of MT expression with the higher grades and invasive growth pattern of RCC. In addition, the incidence of apoptosis increased with increasing immunoreactivity of MT staining. There was a significant difference in the incidence of apoptosis between the diffuse staining and negative staining of MT.

CONCLUSIONS

There were close associations of higher grade RCC with both the incidence of apoptosis and the expression of MT, as well as a close relationship between MT expression and the invasive growth pattern of RCC. This suggests that the involvement of apoptotic cell death and MT expression should be considered an important factor in the process of the renal carcinogenesis and tumour progression.

Assessment of the biologic markers p53, Ki-67, and apoptotic index as predictive indicators of prostate carcinoma recurrence after surgery

BACKGROUND

This study was designed to evaluate the potential of the molecular and cellular markers p53, Ki-67, and apoptotic index (AI) as adjuncts to the commonly available variables of tumor grade, clinical stage, and serum prostate specific antigen to predict prostate carcinoma recurrence after radical prostatectomy.

METHODS

Representative punch biopsy specimens of prostate carcinoma from whole mount paraffin blocks were evaluated from 47 men who underwent radical prostatectomy. Two groups were defined: those without evidence of prostate carcinoma recurrence after 5 years of follow-up (N = 30) and those with carcinoma recurrence (N = 17). Gleason grade, clustered p53 immunostaining, Ki-67 immunostaining, and AI were determined by standard techniques.

RESULTS

All variables tested were associated with disease recurrence by univariate analysis: AI (P = 0.005), clustered p53 immunostaining (P = 0.0070), and Ki-67 immunostaining (P = 0.0390). Using multivariate analyses that included each biomarker with routinely available features, only AI (P = 0.0234) and clustered p53 immunostaining (P = 0.0389) added independent prognostic information (Ki-67 immunostaining, P = 0.1285). In the final logistic regression model that included standard variables with AI and p53, only AI reached statistical significance (P = 0.0332).

CONCLUSIONS

The continued assessment of additional biomarkers for prostate carcinoma recurrence is important to identify better those patients who may be candidates for early adjuvant therapy and also to further our understanding of the neoplastic potential of a particular malignancy.

Apoptotic frequency is increased in spermatogenic maturation arrest and hypospermatogenic states

PURPOSE

Increased testicular apoptosis has been observed in maturation arrest and hyposper-matogenesis states in rodent models, but this process has not yet been characterized in humans. We hypothesized that increased cell death present with accelerated apoptosis is significant in pathophysiology of many male infertility states associated with abnormal spermatogenesis. We examined frequency of apoptotic bodies in human testis biopsy specimens from infertile men using morphometric analysis of hematoxylin and eosin stained paraffin sections.

MATERIALS AND METHODS

Testis biopsy specimens were obtained for routine clinical purposes from azoospermic and severely oligozoospermic men and were stained with hematoxylin and eosin. Apoptotic bodies were identified using established morphometric criteria. Apoptotic indexes, defined as apoptotic bodies per total number of cells and per Sertoli cells, were calculated after counting all intratubular spermatogenic cells and Sertoli cells in 20 tubules.

RESULTS

A total of 51 biopsies was performed in 50 men. Significantly increased apoptotic body per total cell and apoptotic body per Sertoli cell ratios were observed in maturation arrest and hypospermatogenesis states in comparison to Sertoli cell only and normal spermatogenesis (p < 0.05, Mann-Whitney test).

CONCLUSIONS

Increased apoptosis in maturation arrest and hypospermatogenesis states compared to normal but obstructed spermatogenesis and Sertoli cell only were observed, indicating a prominent role for this form of programmed cell death in human male infertility.

Extent of apoptosis in ovarian serous carcinoma: relation to mitotic and proliferative indices, p53 expression, and survival

AIMS

To assess the extent of apoptosis in ovarian serous carcinoma and to examine possible relations between apoptosis, cell proliferation, p53 overexpression, and patient survival.

METHODS

Apoptotic and mitotic indices were obtained by examining haematoxylin and eosin stained sections from 30 patients with ovarian serous carcinoma. Apoptosis was also evaluated semiquantitatively by in situ end labelling of fragmented DNA. Expression of p53 and determination of Ki-67 labelling indices were based on immunohistochemical staining. Clinical details were obtained from patients' clinical records. For statistical analysis, Fisher's exact test, parametric (Pearson) linear correlations, and the Kaplan-Meier method were used.

RESULTS

The mean apoptotic index was 1.3% (range 0.02-3.9%), the mean mitotic index was 0.4% (range 0.02-1.1%), and the mean Ki-67 labelling index was 16% (range 4-32%). There were significant correlations between the apoptotic and mitotic indices (p < 0.0205) and between the mitotic and Ki-67 labelling indices (p < 0.024). There was a significant correlation between a high apoptotic index and poor prognosis (p < 0.02). p53 was overexpressed in 16 cases but the extent of apoptosis and outcome were both independent of p53 status.

CONCLUSIONS

These results suggest that regulation of apoptosis is an integral component of tumour cell kinetics in ovarian serous carcinoma, and that increased apoptosis is indicative of aggressive tumour growth. p53 expression did not correlate with altered apoptosis, but the possibility of an attenuated apoptotic response to subsequent DNA damage by anticancer agents is not excluded.

Apoptotic index in ovarian carcinoma: correlation with clinicopathologic factors and prognosis

The apoptotic index (apoptotic cells/1000 tumor cells, AI) was evaluated in 71 ovarian carcinomas, all surgically resected. Apoptosis was examined by modified terminal deoxynucleotidyltransferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) method in histologic sections. High AI (>/=2.8) significantly correlated with high mitotic index (P = 0.05), high histologic grade of the tumor (P = 0. 018), and short overall survival (P = 0.017). An inverse relationship between AI and bcl-2 protein expression was also observed (P = 0.007). In addition, AI was assessed in 5 ovarian epithelial tumors of borderline malignancy, and all were categorized as low AI (<2.8). No significant correlation was found between AI and other clinicopathologic factors, such as age, clinical stage, lymph node metastasis, tumor size, histology of the tumor, and expression of p53 protein. Multivariate survival analysis showed that only clinical stage (P = 0.0395) and mitotic index (P = 0.0387) had independent prognostic value, whereas AI did not. Our results suggest that counting apoptosis can be useful for predicting the patient survival in ovarian carcinoma, although AI is not an independent prognostic factor. It is also suggested that bcl-2 protein is an important regulator of apoptosis in ovarian carcinoma.

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.

A high apoptotic index occurs in subtypes of endometrial adenocarcinoma associated with a poor prognosis

A study was carried out to determine the apoptotic index (AI) in cases of endometrial adenocarcinoma that are usually associated with a poor prognosis, and to identify in the AI in these cases differs from the AI's in grade I and II endometrial adenocarcinoma. The apoptotic index (defined as the percentage of morphologically identified apoptotic cells and apoptotic bodies in counting 3000 tumor cells) was calculated for five grade III endometrial adenocarcinomas of no specific type (NST), five clear cell adenocarcinomas (CCC), three high grade uterine papillary serous carcinomas (UPSC) and one undifferentiated carcinoma of the endometrium. Overall a higher mean AI (6.3%) was identified in these poor prognosis neoplasms than in 13 grade I and II endometrial adenocarcinomas (mean AI 2.7% p < 0.0001). The apoptotic index was highest in the undifferentiated carcinoma (AI = 9.7%). The mean AI for the cases of UPSC, CCC and grade III endometrioid (NST) adenocarcinomas were 7.4%, 5.9% and 5.2% respectively. There was no evidence of a statistically significant difference in the AI in these poor prognosis groups (Kruskall Wallis test p = 0.45). Although the results show that a high AI is a feature of poor prognosis endometrial carcinoma, no distinction in AI was demonstrated in the subtypes examined.

Apoptosis bcl-2 and p53 expression and their relation to tumour stage in non-small cell lung carcinomas (NSCLC)

Little quantitative data exist on the extent of apoptosis (genetically mediated cell deletion) and no data are available on its relation to p53 and bcl-2 expression and on its value as a prognostic factor in NSCLCs. We examined 38 NSCLCs (26 squamous, 8 adeno, 2 adenosquamous and 2 large cell carcinomas) for the frequency of apoptotic bodies by morphometric methods using haematoxylin eosin stained sections and for the bcl-2 and mutant p53 gene product expression using immunohistochemical techniques. We also evaluated the relation of apoptosis, bcl-2 and p53 expression to tumour stage and to each other. Eleven cases were in stage I, 5 were in stage II, 13 were in stage III and 9 were in stage IV. The mean apoptotic count was 9.52 (r: 2-26); 36.8% of cases were positive for bcl-2 and 76.3% of cases were positive for p53 expression. Statistical analysis did not show any correlation between tumour stage and any of the three tested parameters. There was no statistically significant relation between apoptosis and either p53 or bcl-2 expression. There are conflicting reports on the complex relationship between bcl-2, p53 and apoptosis. bcl-2 is suggested to have a prognostic value, independent from stage in SCLCs. Though we did not find any relation between stage and bcl-2 or apoptosis, it remains to be tested whether they have any independent prognostic value in larger series with survival data.

Detection of apoptosis by the TUNEL technique in clinically localised prostatic cancer before and after combined endocrine therapy

AIMS

Apoptosis in prostate cancer was evaluated after three months of combined endocrine therapy to investigate the association with tumour grade, tumour stage, and the immunohistochemical detection of p53 and bcl-2 in tumour cells before and after therapy.

METHODS

Twenty six formalin fixed, paraffin wax embedded core biopsies and corresponding prostatectomy specimens, excised after three months of combined endocrine therapy, were analysed for the presence of apoptotic cells by the terminal deoxynucleotidyl transferase mediated dUTP-biotin nick end labelling (TUNEL) method, and for p53 and bcl-2 overexpression by immunohistochemistry.

RESULTS

All 26 adenocarcinomas were clinically localised at diagnosis. In biopsies performed before combined endocrine therapy, the apoptotic indices varied between 0.09% and 1.73%, while the tumour grade fell between Gleason score 1 and 8. The mean (SD) apoptotic count pretherapy was 0.71% (0.50). There was a significant association between elevated apoptotic counts and higher Gleason scores in the biopsies (p = 0.005). After three months of therapy, the percentage of apoptotic tumour cells increased independently of tumour stage, while a significant association with Gleason grade was found (p = 0.0018) and all the tumours had Gleason scores of < 7. In eight cases the apoptotic index was more than twice its pretherapy value. The remaining tumours showed less of an increase in the apoptotic index (five cases) or a reduction in the percentage of apoptotic cells. The overall moderate increase in apoptotic index after combined endocrine therapy was not statistically significant (p = 0.8). Immunoreactivity to p53 was absent in all cases, before and after therapy, while a slight increase in the number of cells overexpressing bcl-2 was observed in five of the 13 tumours (38.1%) with reduced apoptotic indices after therapy.

CONCLUSIONS

After three months of combined endocrine treatment a minority of clinically localised prostate neoplasms showed regressive epithelial alterations, associated with an increase in apoptotic tumour cells; an increase in cells overexpressing bcl-2 was observed in five of the 13 tumours with reduced apoptotic indices.

The role of apoptosis in gynaecological malignancies

Apoptosis is a process of single-cell deletion requiring active participation of the cell in its own demise. First described in 1972, it is now known to play a major role in embryogenesis, tissue homeostasis and neoplasia. Apoptosis can be initiated when DNA damage occurs causing the cell to pause in its reproductive cycle. If the DNA damage is beyond repair, the cell proceeds to apoptotic cell death. When the genetic mechanism(s) involved in the pathway of apoptosis is altered, the cell does not die. Further mutations occur by proliferation and such multiple mutational events can lead to a malignant phenotype and cancer growth. The tumour suppressor gene p53 causes a DNA-damaged cell to rest and attempt repair. If damage is irreparable, p53 levels will continue to increase, initiating apoptosis. Mutation of p53, found in approximately 50% of cancers, can stop the apoptotic process. Increased bcl-2 expression, an apoptosis inhibitor, also plays a role in cellular transformation and cancer growth. Its altered expression occurs in the presence of oncogene expression. This paper reviews the role of apoptosis in malignant transformation, cancer growth, and response to therapy for gynaecological cancers. For cervical cancer and its precursors, data on apoptotic index, bcl-2 and Bax expression are presented and discussed in relationship to human papillomavirus expression. In ovarian epithelial malignancies, the role that apoptosis plays in chemotherapeutic responses is reviewed. The data for endometrial cancer are currently limited to apoptotic index.

Apoptosis in operated small cell lung carcinoma is inversely related to tumour necrosis and p53 immunoreactivity

The present study was undertaken to analyse the extent of apoptosis in operated small cell lung carcinoma (SCLC) by using in situ labelling of the oligonucleosomal DNA fragments by terminal transferase. The extent of apoptosis was compared with the cell proliferation activity, as determined by Ki-67 immunohistochemistry; with the volume density of necrosis (per cent), as determined by the morphometric point counting method; and with the occurrence of immunohistochemically detectable p53 and bcl-2 proteins. By in situ labelling, remarkably high apoptotic indices (from 0.08 to 8.10 per cent) were seen in SCLC. A high percentage of SCLSs also showed an exceptionally high proliferation activity. Aberrant accumulation of p53 protein was seen in 37.5 per cent and bel-2 overexpression in 50 per cent of SCLCs. Necrosis was seen in 82.5 per cent of SCLCs. The extent of apoptosis was inversely related to the extent of tumour necrosis (P = 0.05) and to p53 protein accumulation (P = 0.008). A positive association was found between the extent of apoptosis and bel-2 immunoreactivity (P = 0.02). The apoptotic indices (per cent) correlated with the age (P < 0.05) and total smoking time of the patients (P = 0.06).