Precision medicine for prostate cancer: An international perspective

Greater personalization of cancer medicine continues to shape therapy development and patient selection accordingly. The treatment of prostate cancer has evolved considerably since the discovery of androgen deprivation therapy. The comprehensive profiling of the prostate cancer genome has mapped the targetable molecular landscape of the disease and identified opportunities for the implementation of novel and combination therapies. In this review, we provide an overview of the molecular biology of prostate cancer and tools developed to aid prognostication and prediction of therapy benefit. Modern treatment of advanced prostate cancer is reviewed as a paradigm of increasing precision-informed approach to patient care, and must be considered on a global scale with respect to the state of science and care delivery.

Detection of PSMA expression on circulating tumor cells by blood-based liquid biopsy in prostate cancer

Background

For patients with mCRPC, PSMA-targeted radioligand treatment has significantly improved the clinical outcome. A blood-based liquid biopsy assay for recognizing PSMA protein expression on circulating tumor cells may be beneficial for better informing therapeutic decision-making and identifying the patients most likely to benefit from PSMA-targeted radioligand therapy.

Methods

Using high-throughput imaging and digital AI pathology algorithms, a four-color immunofluorescence assay has been developed to find PSMA protein expression on CTCs on a glass slide. Cell line cells (LNCaP/PC3s/22Rv1) spiked into healthy donor blood were used to study the precision, specificity, sensitivity, limit of detection, and overall accuracy of the assay. Clinical validation and low-pass whole-genome sequencing were performed in PSMA-PET-positive patients with high-risk mCRPC (N = 24) utilizing 3 mL of blood.

Results

The PSMA CTC IF assay achieved analytical specificity, sensitivity, and overall accuracy above 99% with high precision. In the clinical validation, 76% (16/21) of the cases were PSMA positive with CTC heterogeneity, and 88% (21/24) of the patients contained at least one conventional CTC per milliliter of blood. Thirty-six low-pass-sequenced CTCs from 11 individuals with mCRPC frequently exhibited copy number increases in AR and MYC and losses in RB1, PTEN, TP53, and BRCA2 locus.

Conclusions

The analytical validation utilizing Epic Sciences' liquid biopsy CTC platform demonstrated the potential to detect PSMA protein expression in CTCs from patients with mCRPC. This assay is positioned as an effective research tool to evaluate PSMA expression, heterogeneity, and therapeutic response in many ongoing clinical studies to target tumors that express PSMA.

Metastatic Hormone-Sensitive Prostate Cancer: Toward an Era of Adaptive and Personalized Treatment

The advent of more effective treatment combinations for metastatic hormone-sensitive prostate cancer (mHSPC) has been built on successes in therapy development for metastatic, castration-resistant prostate cancer (mCRPC). Both disease phases hold similar challenges and questions. Is there an optimal therapy sequence to maximize disease control and balance treatment burden? Are there clinical and biologically based subgroups that inform personalized and/or adaptive strategies? How can clinicians interpret data from clinical trials in the context of rapidly evolving technologies? Herein, we review the contemporary landscape of treatment for mHSPC, including disease subgroups informing both intensification and potential deintensification strategies. Furthermore, we provide current insights into the complex biology of mHSPC and discuss the potential clinical application of biomarkers to guide therapy selection and the development of novel personalized approaches.

A novel prostate cancer subtyping classifier based on luminal and basal phenotypes

BACKGROUND

Prostate cancer (PCa) is a clinically heterogeneous disease. The creation of an expression-based subtyping model based on prostate-specific biological processes was sought.

METHODS

Unsupervised machine learning of gene expression profiles from prospectively collected primary prostate tumors (training, n = 32,000; evaluation, n = 68,547) was used to create a prostate subtyping classifier (PSC) based on basal versus luminal cell expression patterns and other gene signatures relevant to PCa biology. Subtype molecular pathways and clinical characteristics were explored in five other clinical cohorts.

RESULTS

Clustering derived four subtypes: luminal differentiated (LD), luminal proliferating (LP), basal immune (BI), and basal neuroendocrine (BN). LP and LD tumors both had higher androgen receptor activity. LP tumors also had a higher expression of cell proliferation genes, MYC activity, and characteristics of homologous recombination deficiency. BI tumors possessed significant interferon γactivity and immune infiltration on immunohistochemistry. BN tumors were characterized by lower androgen receptor activity expression, lower immune infiltration, and enrichment with neuroendocrine expression patterns. Patients with LD tumors had less aggressive tumor characteristics and the longest time to metastasis after surgery. Only patients with BI tumors derived benefit from radiotherapy after surgery in terms of time to metastasis (hazard ratio [HR], 0.09; 95% CI, 0.01-0.71; n = 855). In a phase 3 trial that randomized patients with metastatic PCa to androgen deprivation with or without docetaxel (n = 108), only patients with LP tumors derived survival benefit from docetaxel (HR, 0.21; 95% CI, 0.09-0.51).

CONCLUSIONS

With the use of expression profiles from over 100,000 tumors, a PSC was developed that identified four subtypes with distinct biological and clinical features.

PLAIN LANGUAGE SUMMARY

Prostate cancer can behave in an indolent or aggressive manner and vary in how it responds to certain treatments. To differentiate prostate cancer on the basis of biological features, we developed a novel RNA signature by using data from over 100,000 prostate tumors-the largest data set of its kind. This signature can inform patients and physicians on tumor aggressiveness and susceptibilities to treatments to help personalize cancer management.

Clinical testing of transcriptome-wide expression profiles in high-risk localized and metastatic prostate cancer starting androgen deprivation therapy: an ancillary study of the STAMPEDE abiraterone Phase 3 trial

Metastatic and high-risk localized prostate cancer respond to hormone therapy but outcomes vary. Following a pre-specified statistical plan, we used Cox models adjusted for clinical variables to test associations with survival of multi-gene expression-based classifiers from 781 patients randomized to androgen deprivation with or without abiraterone in the STAMPEDE trial. Decipher score was strongly prognostic (p<2×10-5) and identified clinically-relevant differences in absolute benefit, especially for localized cancers. In metastatic disease, classifiers of proliferation, PTEN or TP53 loss and treatment-persistent cells were prognostic. In localized disease, androgen receptor activity was protective whilst interferon signaling (that strongly associated with tumor lymphocyte infiltration) was detrimental. Post-Operative Radiation-Therapy Outcomes Score was prognostic in localized but not metastatic disease (interaction p=0.0001) suggesting the impact of tumor biology on clinical outcome is context-dependent on metastatic state. Transcriptome-wide testing has clinical utility for advanced prostate cancer and identified worse outcomes for localized cancers with tumor-promoting inflammation.

Navigating the Current Landscape of Non-Clear Cell Renal Cell Carcinoma: A Review of the Literature

Non-clear cell renal cell carcinoma (nccRCC) is an entity comprised of a heterogeneous constellation of RCC subtypes. Genomic profiling has broadened our understanding of molecular pathogenic mechanisms unique to individual nccRCC subtypes. To date, clinical trials evaluating the use of immunotherapies and targeted therapies have predominantly been conducted in patients with clear cell histology. A comprehensive review of the literature has been undertaken in order to describe molecular pathogenic mechanisms pertaining to each nccRCC subtype, and concisely summarise findings from therapeutic trials conducted in the nccRCC space.

Distinct microRNA expression pattern in breast cancer cells following anti-neoplastic treatment: A systematic review and functional analysis of microRNA target genes

Breast cancer remains a significant cause of mortality in females worldwide, despite advances in technology and treatment. MicroRNA expression in breast cancer is studied both as potential biomarkers and for therapeutic purposes. Accumulated evidence revealed microRNA profile of various types of cancer cells following antineoplastic treatment. The progression of research in this area provides better understanding on the anti-cancer mechanism of various natural compounds and drugs specifically on the microRNA regulation. Hence, we aim to systematically review differentially expressed microRNA in MCF-7, a commonly studied breast cancer cell line, after treatment with anti-neoplastic agents. Relevant keywords were used to screen for research articles that reported on the differentially expressed microRNAs in experimental models of MCF-7 before and after anti-neoplastic treatment. Target genes of microRNAs were identified from MiRTarbase and further in silico functional analysis of the target genes were performed using DAVID bioinformatic resources. Two upregulated microRNAs (mir-200c and let-7d) and 3 downregulated microRNAs (mir-27a, mir-27b and mir-203) were identified by highest number of studies. Three microRNAs (let-7a, mir-23a and mir-7) showed inconsistent direction of expression. Genes functional analysis revealed the regulatory effect of microRNA on genes related to angiogenesis, hypoxia, P53, FoxO and PI3K-AKT signalling. Clusters of genes associated to the pathway of angiogenesis, cancers, cell proliferation and apoptosis were noted through protein-protein interaction analysis. MicroRNAs, especially the mir-200c, let-7d, mir-27a, mir-27b and mir-203 from this review could be further validated experimentally to serve as molecular target or biomarkers for anti-neoplastic therapy.

Accumulation of copy number alterations and clinical progression across advanced prostate cancer

BACKGROUND

Genomic copy number alterations commonly occur in prostate cancer and are one measure of genomic instability. The clinical implication of copy number change in advanced prostate cancer, which defines a wide spectrum of disease from high-risk localised to metastatic, is unknown.

METHODS

We performed copy number profiling on 688 tumour regions from 300 patients, who presented with advanced prostate cancer prior to the start of long-term androgen deprivation therapy (ADT), in the control arm of the prospective randomised STAMPEDE trial. Patients were categorised into metastatic states as follows; high-risk non-metastatic with or without local lymph node involvement, or metastatic low/high volume. We followed up patients for a median of 7 years. Univariable and multivariable Cox survival models were fitted to estimate the association between the burden of copy number alteration as a continuous variable and the hazard of death or disease progression.

RESULTS

The burden of copy number alterations positively associated with radiologically evident distant metastases at diagnosis (P=0.00006) and showed a non-linear relationship with clinical outcome on univariable and multivariable analysis, characterised by a sharp increase in the relative risk of progression (P=0.003) and death (P=0.045) for each unit increase, stabilising into more modest increases with higher copy number burdens. This association between copy number burden and outcome was similar in each metastatic state. Copy number loss occurred significantly more frequently than gain at the lowest copy number burden quartile (q=4.1 × 10-6). Loss of segments in chromosome 5q21-22 and gains at 8q21-24, respectively including CHD1 and cMYC occurred more frequently in cases with higher copy number alteration (for either region: Kolmogorov-Smirnov distance, 0.5; adjusted P<0.0001). Copy number alterations showed variability across tumour regions in the same prostate. This variance associated with increased risk of distant metastases (Kruskal-Wallis test P=0.037).

CONCLUSIONS

Copy number alteration in advanced prostate cancer associates with increased risk of metastases at diagnosis. Accumulation of a limited number of copy number alterations associates with most of the increased risk of disease progression and death. The increased likelihood of involvement of specific segments in high copy number alteration burden cancers may suggest an order underlying the accumulation of copy number changes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT00268476 , registered on December 22, 2005. EudraCT  2004-000193-31 , registered on October 4, 2004.

Lifetime Health and Economic Outcomes of Active Surveillance, Radical Prostatectomy, and Radiotherapy for Favorable-Risk Localized Prostate Cancer

OBJECTIVES

To estimate the lifetime health and economic outcomes of selecting active surveillance (AS), radical prostatectomy (RP), or radiation therapy (RT) as initial management for low- or favorable-risk localized prostate cancer.

METHODS

A discrete-event simulation model was developed using evidence from published randomized trials. Health outcomes were measured in life-years and quality-adjusted life-years (QALYs). Costs were included from a public payer perspective in Australian dollars. Outcomes were discounted at 5% over a lifetime horizon. Probabilistic and scenario analyses quantified parameter and structural uncertainty.

RESULTS

A total of 60% of patients in the AS arm eventually received radical treatment (surgery or radiotherapy) compared with 90% for RP and 91% for RT. Although AS resulted in fewer treatment-related complications, it led to increased clinical progression (AS 40.7%, RP 17.6%, RT 19.9%) and metastatic disease (AS 13.4%, RP 6.1%, RT 7.0%). QALYs were 10.88 for AS, 11.10 for RP, and 11.13 for RT. Total costs were A$17 912 for AS, A$15 609 for RP, and A$15 118 for RT. At a willingness to pay of A$20 000/QALY, RT had a 61.4% chance of being cost-effective compared to 38.5% for RP and 0.1% for AS.

CONCLUSIONS

Although AS resulted in fewer and delayed treatment-related complications, it was not found to be a cost-effective strategy for favorable-risk localized prostate cancer over a lifetime horizon because of an increase in the number of patients developing metastatic disease. RT was the dominant strategy yielding higher QALYs at lower cost although differences compared with RP were small.

Transcriptional profiling of primary prostate tumor in metastatic hormone-sensitive prostate cancer and association with clinical outcomes: correlative analysis of the E3805 CHAARTED trial

BACKGROUND

The phase III CHAARTED trial established upfront androgen-deprivation therapy (ADT) plus docetaxel (D) as a standard for metastatic hormone-sensitive prostate cancer (mHSPC) based on meaningful improvement in overall survival (OS). Biological prognostic markers of outcomes and predictors of chemotherapy benefit are undefined.

PATIENTS AND METHODS

Whole transcriptomic profiling was performed on primary PC tissue obtained from patients enrolled in CHAARTED prior to systemic therapy. We adopted an a priori analytical plan to test defined RNA signatures and their associations with HSPC clinical phenotypes and outcomes. Multivariable analyses (MVAs) were adjusted for age, Eastern Cooperative Oncology Group status, de novo metastasis presentation, volume of disease, and treatment arm. The primary endpoint was OS; the secondary endpoint was time to castration-resistant PC.

RESULTS

The analytic cohort of 160 patients demonstrated marked differences in transcriptional profile compared with localized PC, with a predominance of luminal B (50%) and basal (48%) subtypes, lower androgen receptor activity (AR-A), and high Decipher risk disease. Luminal B subtype was associated with poorer prognosis on ADT alone but benefited significantly from ADT + D [OS: hazard ratio (HR) 0.45; P = 0.007], in contrast to basal subtype which showed no OS benefit (HR 0.85; P = 0.58), even in those with high-volume disease. Higher Decipher risk and lower AR-A were significantly associated with poorer OS in MVA. In addition, higher Decipher risk showed greater improvements in OS with ADT + D (HR 0.41; P = 0.015).

CONCLUSION

This study demonstrates the utility of transcriptomic subtyping to guide prognostication in mHSPC and potential selection of patients for chemohormonal therapy, and provides proof of concept for the possibility of biomarker-guided selection of established combination therapies in mHSPC.

NF-κB Blockade with Oral Administration of Dimethylaminoparthenolide (DMAPT), Delays Prostate Cancer Resistance to Androgen Receptor (AR) Inhibition and Inhibits AR Variants

NF-κB activation has been linked to prostate cancer progression and is commonly observed in castrate-resistant disease. It has been suggested that NF-κB-driven resistance to androgen-deprivation therapy (ADT) in prostate cancer cells may be mediated by aberrant androgen receptor (AR) activation and AR splice variant production. Preventing resistance to ADT may therefore be achieved by using NF-κB inhibitors. However, low oral bioavailability and high toxicity of NF-κB inhibitors is a major challenge for clinical translation. Dimethylaminoparthenolide (DMAPT) is an oral NF-κB inhibitor in clinical development and has already shown favorable pharmacokinetic and pharmacodyanamic data in patients with heme malignancies, including decrease of NF-κB in circulating leuchemic blasts. Here, we report that activation of NF-κB/p65 by castration in mouse and human prostate cancer models resulted in a significant increase in AR variant-7 (AR-V7) expression and modest upregulation of AR. In vivo castration of VCaP-CR tumors resulted in significant upregulation of phosphorylated-p65 and AR-V7, which was attenuated by combination with DMAPT and DMAPT increased the efficacy of AR inhibition. We further demonstrate that the effects of DMAPT-sensitizing prostate cancer cells to castration were dependent on the ability of DMAPT to inhibit phosphorylated-p65 function. IMPLICATIONS: Our study shows that DMAPT, an oral NF-κB inhibitor in clinical development, inhibits phosphorylated-p65 upregulation of AR-V7 and delays prostate cancer castration resistance. This provides rationale for the development of DMAPT as a novel therapeutic strategy to increase durable response in patients receiving AR-targeted therapy.

Association between CD8 and PD-L1 expression and outcomes after radical prostatectomy for localized prostate cancer

BACKGROUND

Characterization of markers of both immune suppression and activation may provide more prognostic information than assessment of single markers in localized prostate cancer. We therefore sought to determine the association between CD8 and PD-L1 expression in localized prostate tumors and biochemical recurrence (BCR) and metastasis-free survival (MFS).

METHODS

Tissue microarrays were constructed on 109 men undergoing radical prostatectomy (RP) for localized prostate cancer at Dana-Farber Cancer Institute between 1991 and 2008. Fluorescence immunohistochemistry was used to evaluate the expression of six immune markers (CD3, CD4, CD8, PD-1, PD-L1, FOXP3). Quantitative multispectral imaging analysis was used to calculate the density of each marker, which was dichotomized by the median as "high" or "low." Cox proportional hazards regression models and Kaplan-Meier analyses were used to analyze associations between immune marker densities and time to BCR and MFS.

RESULTS

Over a median follow-up of 8.1 years, 55 (51%) and 39 (36%) men developed BCR and metastases, respectively. Median time to BCR was shorter in men with low CD8 (hazard ratio [HR] = 2.27 [1.27-4.08]) and high PD-L1 expression (HR = 2.03 [1.17-3.53]). While neither low CD8 or high PD-L1 alone were independent predictors of BCR or MFS on multivariable analysis, men with low CD8 and/or high PD-L1 had a significantly shorter time to BCR (median 3.5 years vs. NR) and MFS (median 10.8 vs. 18.4 years) compared to those with high CD8 and low PD-L1 expression. The main limitation is the retrospective and singe-center nature of the study.

CONCLUSION

The presence of higher CD8 and lower PD-L1 expression in prostatectomy specimens was associated a low risk of biochemical relapse and metastatic disease. These findings are hypothesis-generating and further study is needed.

Impact of baseline serum IL-8 on metastatic hormone-sensitive prostate cancer outcomes in the Phase 3 CHAARTED trial (E3805)

BACKGROUND

The immunosuppressive cytokine interleukin- 8 (IL-8), produced by tumor cells and some myeloid cells, promotes inflammation, angiogenesis, and metastasis. In our discovery work, elevated serum IL-8 at androgen deprivation therapy (ADT) initiation portended worse overall survival (OS). Leveraging serum samples from the phase 3 CHAARTED trial of patients treated with ADT +/- docetaxel for metastatic hormone-sensitive prostate cancer (mHSPC), we validated these findings.

METHODS

Two hundred and thirty-three patients had serum samples drawn within 28 days of ADT initiation. The samples were assayed using the same Mesoscale Multiplex ELISA platform employed in the discovery cohort. After adjusting for performance status, disease volume, and de novo/metachronous metastases, multivariable Cox proportional hazards models assessed associations between IL-8 as continuous and binary variables on OS and time to castration-resistant prostate cancer (CRPC). The median IL-8 level (9.3 pg/ml) was the a priori binary cutpoint. Fixed-effects meta-analyses of the discovery and validation sets were performed.

RESULTS

Higher IL-8 levels were prognostic for shorter OS (continuous: hazard ratio [HR] 2.2, 95% confidence interval [CI]: 1.4-3.6, p = .001; binary >9.3: HR 1.7, 95% CI: 1.2-2.4, p = .007) and time to CRPC (continuous: HR 2.3, 95% CI: 1.6-3.3, p < .001; binary: HR 1.8, 95% CI: 1.3-2.5, p < .001) and independent of docetaxel use, disease burden, and time of metastases. Meta-analysis including the discovery cohort, also showed that binary IL-8 levels >9.3 pg/ml from patients treated with ADT alone was prognostic for poorer OS (HR 1.8, 95% CI: 1.2-2.7, p = .007) and shorter time to CRPC (HR 1.4, 95% CI: 0.99-1.9, p = .057).

CONCLUSIONS

In the phase 3 CHAARTED study of men with mHSPC at ADT initiation, elevated IL-8 portended worse survival and shorter time to castration-resistant prostate cancer independent of docetaxel administration, metastatic burden, and metachronous versus de novo metastatic presentation. These findings support targeting IL-8 as a strategy to improve mHSPC outcomes.

Association of Inherited Pathogenic Variants in Checkpoint Kinase 2 (CHEK2) With Susceptibility to Testicular Germ Cell Tumors

Importance

Approximately 50% of the risk for the development of testicular germ cell tumors (TGCTs) is estimated to be heritable, but no mendelian TGCT predisposition genes have yet been identified. It is hypothesized that inherited pathogenic DNA repair gene (DRG) alterations may drive susceptibility to TGCTs.

Objective

To systematically evaluate the enrichment of germline pathogenic variants in the mendelian cancer predisposition DRGs in patients with TGCTs vs healthy controls.

Design, Setting, and Participants

A case-control enrichment analysis was performed from January 2016 to May 2018 to screen for 48 DRGs in 205 unselected men with TGCT and 27 173 ancestry-matched cancer-free individuals from the Exome Aggregation Consortium cohort in the discovery stage. Significant findings were selectively replicated in independent cohorts of 448 unselected men with TGCTs and 442 population-matched controls, as well as 231 high-risk men with TGCTs and 3090 ancestry-matched controls. Statistical analysis took place from January to May 2018.

Main Outcomes and Measures

Gene-level enrichment analysis of germline pathogenic variants in individuals with TGCTs relative to cancer-free controls.

Results

Among 205 unselected men with TGCTs (mean [SD] age, 33.04 [9.67] years), 22 pathogenic germline DRG variants, one-third of which were in CHEK2 (OMIM 604373), were identified in 20 men (9.8%; 95% CI, 6.1%-14.7%). Unselected men with TGCTs were approximately 4 times more likely to carry germline loss-of-function CHEK2 variants compared with cancer-free individuals from the Exome Aggregation Consortium cohort (odds ratio [OR], 3.87; 95% CI, 1.65-8.86; nominal P = .006; q = 0.018). Similar enrichment was also seen in an independent cohort of 448 unselected Croatian men with TGCTs (mean [SD] age, 31.98 [8.11] years) vs 442 unselected Croatian men without TGCTs (at least 50 years of age at time of sample collection) (OR, >1.4; P = .03) and 231 high-risk men with TGCTs (mean [SD] age, 31.54 [9.24] years) vs 3090 men (all older than 50 years) from the Penn Medicine Biobank (OR, 6.30; 95% CI, 2.34-17.31; P = .001). The low-penetrance CHEK2 variant (p.Ile157Thr) was found to be a Croatian founder TGCT risk variant (OR, 3.93; 95% CI, 1.53-9.95; P = .002). Individuals with the pathogenic CHEK2 loss-of-function variants developed TGCTs 6 years earlier than individuals with CHEK2 wild-type alleles (5.95 years; 95% CI, 1.48-10.42; P = .009).

Conclusions and Relevance

This multicenter case-control analysis of men with or without TGCTs provides evidence for CHEK2 as a novel moderate-penetrance TGCT susceptibility gene, with potential clinical utility. In addition to highlighting DNA-repair deficiency as a potential mechanism driving TGCT susceptibility, this analysis also provides new avenues to explore management strategies and biological investigations for high-risk individuals.

Outcome of Men With Relapses After Adjuvant Bleomycin, Etoposide, and Cisplatin for Clinical Stage I Nonseminoma

PURPOSE

Clinical stage I (CSI) nonseminoma (NS) is a disease limited to the testis without metastases. One treatment strategy after orchiectomy is adjuvant chemotherapy. Little is known about the outcome of patients who experience relapse after such treatment.

PATIENTS AND METHODS

Data from 51 patients with CSI NS who experienced a relapse after adjuvant bleomycin, etoposide, and cisplatin (BEP) from 18 centers/11 countries were collected and retrospectively analyzed. Primary outcomes were overall and progression-free survivals calculated from day 1 of treatment at first relapse. Secondary outcomes were time to, stage at, and treatment of relapse and rate of subsequent relapses.

RESULTS

Median time to relapse was 13 months, with the earliest relapse 2 months after start of adjuvant treatment and the latest after 25 years. With a median follow-up of 96 months, the 5-year PFS was 67% (95% CI, 54% to 82%) and the 5-year OS was 81% (95% CI, 70% to 94%). Overall, 19 (37%) of 51 relapses occurred later than 2 years. Late relapses were associated with a significantly higher risk of death from NS (hazard ratio, 1.10 per year; P = .01). Treatment upon relapse was diverse: the majority of patients received a combination of chemotherapy and surgery. Twenty-nine percent of patients experienced a subsequent relapse. At last follow-up, 41 patients (80%) were alive and disease-free, eight (16%) had died of progressive disease, and one patient (2%) each had died from therapy-related or other causes.

CONCLUSION

Outcomes of patients with relapse after adjuvant BEP seem better compared with patients who experience relapse after treatment of metastatic disease but worse compared with those who have de-novo metastatic disease. We found a substantial rate of late and subsequent relapses. There seem to be three patterns of relapse with different outcomes: pure teratoma, early viable NS relapse (< 2 years), and late viable NS relapse (> 2 years).

Abstract B038: Dimethylaminoparthenolide-mediated inhibition of NF-κB decreases resistance to ADT by targeting AR variants in lethal prostate cancer

Background: Inflammation, mediated by NF-κB, is linked to prostate cancer (PCa) progression and is commonly observed in castrate-resistant disease. We have previously shown that low expression of tristetraprolin (TTP), which modulates the NF-κB pathway and inflammation, is prognostic for lethal PCa after surgery. It has been suggested that NF-κB-driven resistance in PCa cells may be mediated by aberrant androgen receptor (AR) activation and AR splice variant production. Reversal of resistance to androgen deprivation therapy (ADT) may therefore be achieved by utilizing NF-κB inhibitors, such as dimethylaminoparthenolide (DMAPT). Materials and Methods: To examine clinical correlations between TTP/NF-κB and AR-V7, gene-expression profiling data and clinical data was obtained from several publicly available PCa cohorts (TCGA, SU2C, Taylor et. al.). Quantitative immunofluorescence for TTP and PTEN was performed on tissue microarrays from a clinical cohort of patients treated by radical prostatectomy with known time to biochemical recurrence (BCR). In vitro, mouse (MYC-CaP) and human (VCaP-CR, LNCaP-95) PCa cell lines were treated with TNF-α (20 ng/mL) to stimulate NF-κB expression, DMAPT (5-10 μM) to inhibit NF-κB and Enzalutamide (10 μM) in various combinations. Cell lines stably expressing the IκBα super repressor (MUT IκBα) were generated for comparison to DMAPT-mediated inhibition of NF-κB. Expression of AR and AR variants was measured by western blot and qPCR. For in vivo experiments, SCID mice bearing VCaP-CR xenograft tumors were treated with surgical castration, DMAPT (100 mg/kg, oral gavage, QD), surgical castration plus DMAPT or water vehicle control (n = 7-8 per group). Xenograft tumors were measured thrice weekly until they reached an ethical endpoint or after 80 days of treatment. Time-to-progression of tumors was assessed by Kaplan-Meier analysis and molecular differences within tumors analyzed by qPCR and immunohistochemistry (IHC). Results: In multiple clinical PCa cohorts, reduced TTP expression correlated with an increased AR-V7 signature. In a cohort of patients with localized PCa, decreased TTP expression reduced time to BCR and co-loss of TTP and PTEN (a known PCa tumor suppressor) further decreased time to BCR. Activation of NF-κB in PCa cell lines resulted in a significant increase in AR variant expression and minor upregulation of AR. Chemical (DMAPT) and genetic (MUT IκBα) inhibition of NF-κB slowed tumor proliferation and decreased AR variant expression. Treatment of PCa cell lines with Enzalutamide resulted in AR variant upregulation, which was blocked by DMAPT. Castration of mice bearing VCaP-CR tumors significantly increased AR and AR-V7 tumor expression. DMAPT treatment reduced NF-κB and AR-V7 expression in xenograft tumors, but did not significantly alter tumor growth compared to vehicle treatment. The combination of castration and DMAPT slowed median time-to-progression of xenograft tumors compared to vehicle-treated tumors (79 and 36 days respectively, p &lt; 0.001). Combination therapy decreased Ki-67 (IHC), AR-V7 and AR (IHC and qPCR) expression in xenograft tumors. Conclusions: Current treatments for PCa mainly target AR; however, despite initial response, these treatments commonly fail. Our data highlight the relationship between NF-κB and AR variant expression in aggressive PCa and support the rationale for clinical use of DMAPT to treat castrate-resistant tumors in combination with AR antagonists.

Citation Format: Katherine L Morel, Anis A Hamid, Leigh Ellis, Christopher J Sweeney. Dimethylaminoparthenolide-mediated inhibition of NF-κB decreases resistance to ADT by targeting AR variants in lethal prostate cancer [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B038. doi:10.1158/1535-7163.TARG-19-B038

Large retroperitoneal lymphadenopathy and increased risk of venous thromboembolism in patients receiving first-line chemotherapy for metastatic germ cell tumors: A study by the global germ cell cancer group (G3)

Background

Metastatic germ cell tumor (mGCT) patients receiving chemotherapy have increased risk of life‐threatening venous thromboembolism (VTE). Identifying VTE risk factors may guide thromboprophylaxis in this highly curable population.

Methods

Data were collected from mGCT patients receiving first‐line platinum‐based chemotherapy at 22 centers. Predefined variables included International Germ Cell Cancer Collaborative Group (IGCCCG) risk classification, long‐axis diameter of largest retroperitoneal lymph node (RPLN), Khorana score, and use of indwelling vascular access device (VAD). VTE occurring at baseline, during chemotherapy and within 90 days, was analyzed.

Results

Data from 1135 patients were collected. Median age was 31 years (range 10‐74). IGCCCG risk was 64% good, 20% intermediate, and 16% poor. VTE occurred in 150 (13%) patients. RPLN >3.5 cm demonstrated highest discriminatory accuracy for VTE (AUC 0.632, P < .001) and was associated with significantly higher risk of VTE in univariable analysis (22% vs 8%, OR 3.0, P < .001) and multivariable analysis (OR 1.8, P = .02). Other significant risk factors included, Khorana score ≥3 (OR 2.6, P = .008) and VAD use (OR 2.7, P < .001).

Conclusions

Large RPLN and VAD use are independent risk factors for VTE in mGCT patients receiving chemotherapy. VAD use should be minimized in this population and thromboprophylaxis might be considered for large RPLN.

Clinical Trials of Metastatic Castration-sensitive Prostate Cancer: Recent Progress and New Horizons

Recent clinical trials have changed the treatment landscape for metastatic castration-sensitive prostate cancer. Ongoing and future studies using new therapeutic approaches hold the promise of further improving outcomes for patients with advanced prostate cancer.

Compound Genomic Alterations of TP53, PTEN, and RB1 Tumor Suppressors in Localized and Metastatic Prostate Cancer

BACKGROUND

TP53, PTEN, and RB1 tumor suppressor genes (TSGs) are recurrently altered in treatment-resistant prostate cancer. Cooperative loss of two or more TSGs may drive more aggressive disease.

OBJECTIVE

To determine clinical outcomes of single and compound TSG alterations across the spectrum of prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

Massively parallel targeted sequencing using castration-sensitive prostate cancer (CSPC; localized [L] and metastatic [M1]) and castration-resistant prostate cancer (CRPC) specimens (n=285). TSG altered (TSG-alt) was any copy number loss or deleterious mutation of one or more TSGs (TP53, PTEN, and RB1).

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

For L-CSPC, event-free survival (EFS) and time to CRPC were estimated. For M1-CSPC and M1-CRPC, overall survival (OS) was estimated. Cox regression models assessed the association between cumulative TSG hits (zero hits vs one hit vs two to three hits) and outcomes with multivariable analyses adjusted for clinicopathological factors.

RESULTS AND LIMITATIONS

TSG variants increased with advanced disease (L-CSPC: 39%; M1-CSPC: 63%, M1-CRPC: 92%). TSG-alt L-CSPC had shorter EFS (median 2.6yr, hazard ratio [HR] 1.95, 95% confidence interval [CI] 1.22-3.13) and time to CRPC (median 9.5mo, HR 3.36, 95% CI 1.01-11.16). Cumulative gene hits led to an incremental risk of relapse (EFS: one gene, HR 1.69, 95% CI 0.99-2.87; two to three genes, HR 2.70, 95% CI 1.43-5.08; both versus zero genes, p=0.004). There was evidence of inferior OS with increasing TSG hits in the metastatic cohorts. Only four (8%) patients in the M1-CRPC cohort were TSG-neg, one of whom died after 5.2yr. Multivariable analyses adjusting for mutational and copy number burden did not demonstrate a significant independent association of increasing gene hits and poorer outcomes.

CONCLUSIONS

Deleterious TSG variants are associated with an increased risk of relapse (L) and death (M1) in CSPC. Poorer outcomes are seen with compound gene hits in both early and advanced disease, and this may in part reflect increasing global genomic instability.

PATIENT SUMMARY

Men with prostate tumors with compound tumor suppressor gene mutations have poorer outcomes. These findings help identify patients with aggressive features who may benefit from intensified treatment.

(22β,25R)-3β-Hydroxy-spirost-5-en-7-iminoxy-heptanoic acid exhibits anti-prostate cancer activity through caspase pathway

Prostate cancer is one of the most common cancers in men. Diosgenin and related compounds are potential cytotoxic agents. Twelve diverse analogues of long chain fatty acid/ester of diosgenin-7-ketoxime have been prepared. Six of the analogues exhibited significant anticancer activity against a panel of human cancer cell lines with IC₅₀ ranging from 12 to 35μM. Compound 16, the best representative of the series exerted S phase arrest in DU145 prostate cancer cells and induced apoptosis through caspase pathway. Additionally, these analogues inhibited lipopolysaccharide induced pro-inflammatory cytokines (TNF-α and IL-6) up to 47.7% and 23.3% respectively. Compound 16 was found to be safe in acute oral toxicity in Swiss albino mice up to 300mg/kg dose. The anticancer and antiinflammatory properties of compound 16 are important and can further be optimized for a better anti-prostate cancer candidate.

Synthesis of diosgenin analogues as potential anti-inflammatory agents

We herein report the synthesis of diosgenin analogues from commercially available diosgenin as the starting material. The structures of newly synthesised compounds were confirmed by (1)H NMR, (13)C NMR and mass spectrometry. All analogues were evaluated for in-vitro anti-inflammatory profile against LPS-induced inflammation in primary peritoneal macrophages isolated from mice by quantification of pro-inflammatory (TNF-α, IL-6 and IL-1β) cytokines in cell culture supernatant using the ELISA technique followed by in-vitro cytotoxicity study. Among the synthesised analogues, analogue 15 [(E) 26-(3',4',5'-trimethoxybenzylidene)-furost-5en-3β-acetate)] showed significant anti-inflammatory activity by inhibiting LPS-induced pro-inflammatory cytokines in a dose-dependent manner without any cytotoxicity. Efficacy and safety of analogue 15 were further validated in an in-vivo system using LPS-induced sepsis model and acute oral toxicity in mice. Oral administration of analogue 15 inhibited the pro-inflammatory cytokines in serum, attenuated the liver and lung injury and reduced the mortality rate in sepsis mice. Acute oral toxicity study showed that analogue 15 is non-toxic at higher dose in BALB/c mice. Molecular docking study revealed the strong binding affinity of diosgenin analogues to the active site of the pro-inflammatory proteins. These findings suggested that analogue 15 may be a useful therapeutic candidate for the treatment of inflammatory diseases.

Synthesis of novel anticancer agents through opening of spiroacetal ring of diosgenin

Diosgenin has been modified to furostane derivatives after opening the F-spiroacetal ring. The aldehyde group at C26 in derivative 8 was unexpectedly transformed to the ketone 9. The structure of ketone 9 was confirmed by spectroscopy and finally by X-ray crystallography. Five of the diosgenin derivatives showed significant anticancer activity against human cancer cell lines. The most potent molecule of this series i.e. compound 7, inhibited cellular growth by arresting the population at G0/G1 phase of cell division cycle. Cells undergo apoptosis after exposure to the derivative 7 which was evident by increase in sub G0 population in cell cycle analysis. Docking experiments showed caspase-3 and caspase-9 as possible molecular targets for these compounds. This was further validated by cleavage of PARP, a caspase target in apoptotic pathway. Compound 7 was found non-toxic up to 1000mg/kg dose in acute oral toxicity in Swiss albino mice.

Use of prebiotics in oral delivery of bioactive compounds: a nanotechnology perspective

The oral route is considered the most patient-convenient means of drug administration. In recent years there has been a tendency to employ smart carrier systems that enable controlled or timed release of a bioactive material, thereby providing a better dosing pattern and minimizing side effects. Nano-encapsulation systems (nanocarriers) offer important advantages over conventional drug delivery techniques. Nanocarriers can protect the drug from chemical/enzymatic degradation and enhance bioavailability. Prebiotics are ideal ingredients for the nano-encapsulation and oral drug delivery due to their natural ability to protect the encapsulated compound in the upper gasterointestinal (GI) tract. Here the potential of prebiotics for oral delivery of drugs and other bioactives is reviewed.

Modulation of lipid metabolism by Centella asiatica in oxidative stress rats

A study was carried out to investigate the effects of Centella asiatica leaf on lipid metabolism of oxidative stress rats. The rats were fed 0.1% hydrogen peroxide (H(2)O(2)) with either 0.3% (w/w) C. asiatica extract, 5%C. asiatica powder (w/w), or 0.3% (w/w) alpha-tocopherol for 25 wk. Results of the study showed that C. asiatica powder significantly (P < 0.05) lowered serum low-density lipoprotein compared to that of control rats (rats fed H(2)O(2) only). At the end of the study C. asiatica-fed rats were also found to have significantly (P < 0.05) higher high-density lipoprotein and lower triglyceride level compared to rats fed only normal diet. However, cholesterol level of rats fed both C. asiatica extract and powder was found to be significantly (P < 0.05) higher compared to that of control rats. It was interesting to note that consumption of C. asiatica significantly decreased body and liver weights of the rats. Histological examinations revealed no obvious changes in all rats studied. Quantitative analysis of C. asiatica leaf revealed high concentration of total phenolic compounds, in particular, catechin, quercetin, and rutin.

High prevalence of Pseudomonas species in soil samples from Ternate Island-Indonesia

In the present study, Ten soil samples were examined and the pH of the soil was recorded. For bacterial isolation, a sterile nutrient and blood agars were used. Gram stain and biochemical tests were done for identification. A total of 384 genus were isolated, 314 (81.8%) were identified as Pseudomonas species of which 245 (78.0%) were Pseudomonas aeruginosa, 42 (13.4%) were Pseudomonas fluorescens, 13 (4.2%) were Pseudomonas mallei, 10 (3.1%) were Pseudomonas putida and 4 (1.3%) were Pseudomonas syringe and are regarded as pathogenic and harmful to man, animal and plants. This study shows that Pseudomonas aeruginosa had a high adaptation capability to grow in soil samples from Ternate, Indonesia. The rest of the bacterial isolates (18.2%) were identified as follows: 24 samples (6.2%) were Micrococcus, 23 samples (6.0%) were E. coli, 12 samples (3.1%) were Pasteurella and 11 samples (2.9%) were Staphylococcus. Pencillium was also isolated.

Effect of salts addition on hydrogen production by C. acetobutylicum

The objective of this study is to investigate the effect of salts addition to fermentation medium on hydrogen production, under anaerobic batch culture system. In this study, batch experiments were conducted to investigate the inhibitory effect of both NaCl and sodium acetate on hydrogen production. The optimum pH and temperature for hydrogen production were at initial pH of 7.0 and 30 degrees C. Enhanced production of hydrogen, using glucose as substrate was achieved. In the absence of Sodium Chloride and Sodium Acetate enhanced hydrogen yield (Y(P/S)) from 350 mL g(-1) glucose utilized to 391 mL g(-1) glucose utilized with maximum hydrogen productivity of 77.5 ml/L/h. Results also show that sodium chloride and sodium acetate in the medium adversely affect growth. Hydrogen yield per biomass (Y(P/X)) of 254 ml/L/g, biomass per substrate utilized (Y(X/S)) of 0.268 and (Y(H2/S) of 0.0349. The results suggested that Sodium at any concentration resulted to inhibit the bacterial productivity of hydrogen.

Removal of headspace CO2 increases biological hydrogen production by C. acetobutylicum

The effect of removal of resultant gas resulted in enhancement of the H2 yield. The technique of CO2 scavenging resulted in H2 yield being improved from 408 mL g(-1) to reach the maximum of 422 mL g'. The highest hydrogen productivity of 87.9 ml L(-1) h(-1) was obtained by CO2 scavenging. Biomass concentration was enhanced to 1.47 g L(-1), Y(P,X) of 287 ml g(-1) L(-1), Y(X/S) of 0.294 and Y(H2/s) of 0.0377 by the use of CO2 scavenging. The results suggested that the presence of the gaseous products in fermentation medium and headspace adversely effect biomass growth and hydrogen production.

An outbreak of Newcastle disease in a pheasant flock in Iraq

A highly virulent strain of Newcastle disease virus (NDV) was isolated from pheasants in an unvaccinated private imported flock in the Rathwania area near Baghdad, Iraq, which was suffering from ND. The virus was propagated in 9-day-old specific pathogen-free chicken embryos. It was characterised by the following tests: intracerebral pathogenicity index (ICPI), intravenous pathogenicity index (IVPI), mean death time (MDT), haemagglutinin stability at 56 degrees C and mammalian erythrocyte agglutination. The ICPI, IVPI and MDT for the virus were: 1.89, 2.63 and 64 hours respectively. The stability of its haemagglutinin at 56 degrees C was 120 minutes. It agglutinated chicken and pheasant but not bovine, equine and human type "O" erythrocytes.

Enhancement of biodegradation of crude petroleum-oil in contaminated water by the addition of nitrogen sources

Addition of nitrogen sources as supplementary nutrient into MSM medium to enhance biodegradation by stimulating the growth four isolates, Acinetobacter faecalis, Staphylococcus sp., Pseudomonas putida and Neisseria elongata isolated from petroleum contaminated groundwater, wastewater aeration pond and biopond at the oil refinery Terengganu Malaysia was investigated. The organic nitrogen sources tested not only supported growth but also enhances biodegradation of 1% Tapis crude oil. All four isolates showed good growth especially when peptone was employed as the organic nitrogen compared to growth in the basal medium. Gas chromatography showed that more then 91, 93, 94 and 95% degradation of total hydrocarbon was observed after 5 days of incubation by isolates Pseudomonas putida, Neisseria elongate, Acinetobacter faecalis and Staphylococcus sp., respectively.

Effect of some environmental parameters on hydrogen production using C. acetobutylicum

The aim of this study was to investigate the influence of some environmental factors on bacterial metabolism. Fermentative hydrogen production by C. acetobutylicum, using glucose as the substrate. The effect of initial pH (4-8), inoculum size (1-20% (v/v)) and glucose concentration (1-30 g L(-1)) on hydrogen production were studied. The optimum cultivation temperature for hydrogen production was at 30 degrees C. The results show that substrate concentration and inoculum size resulted in hydrogen yield (Y(P/S)) of 391 mL g(-1) glucose utilized with maximum hydrogen productivity of 77.5 mL/L/h. Higher substrate concentration or inoculum size adversely affects hydrogen production, which decreases hydrogen yield by 15% to 334 mL g(-1) glucose utilized when 30% (v/v) inoculum size was used. The use of 30 g L(-1) substrate concentration resulted in a 75% decrease to 97 mL g(-1) glucose supplied. Concluded that proper Xo/So enhanced the hydrogen production.

Differential gene expression of human adipose-derived stem cells in osteogenic induction

Human adipose-derived stem cells (HADSC) have demonstrated the capacity of differentiating into bone depending on the specific induction stimuli and growth factors. However, investigation on stem cell characteristic after osteogenic differentiation is still lacking. The goal of this study was to investigate the differential expression of sternness and osteogenic genes in non-induced HADSC compared with HADSC after osteogenic induction using quantitative Real Time RT-PCR. Our results showed that OCT-4, REX-1, FZD9, OSC, RUNX, and ALP were up regulated after osteogenic induction. This may indicated that HADSCs after osteogenic induction still possessed some stemness properties.

C-erbB-2 or mutant Ha-ras induced malignant transformation of immortalized human ovarian surface epithelial cells in vitro

Ovarian cancer is believed to develop from the ovarian surface epithelium through the accumulation of aberrations of oncogenes and/or tumor suppressor genes. However, it is unclear how the gene abnormalities are involved in ovarian carcinogenesis. To elucidate the process, we transfected genes reported to show their abnormalities in human ovarian cancers into human ovarian surface epithelial cells. Immortalization of the cells was achieved by the transfection of SV40 large T antigen (LT) and human telomerase reverse transcriptase (hTERT); however, the resultant cells showed no tumorigenesis. Additional transfection of either c-erbB-2 or mutant Ha-ras into the immortalized cells showed the anchorage-independent growth and tumorigenesis in mice with the incidence of 50% and 40%, respectively. Histologically, all the tumours were undifferentiated. In association with the tumorigenesis, the cells expressing c-erbB-2 or mutant Ha-ras demonstrated increased vascular endothelial growth factor secretion under hypoxia and enhanced resistance to apoptosis compared with the immortalized cells. Collectively, the introduction of either c-erbB-2 or mutant Ha-ras in the cells, which were efficiently immortalized by the transfection of LT and hTERT, showed tumorigenicity, suggesting that c-erbB-2 or mutant Ha-ras genes might be involved in ovarian carcinogenesis.

Resource use of insect seed predators during general flowering and seeding events in a Bornean dipterocarp rain forest

Insect seed predators of 24 dipterocarp species (including the genera ot Dipterocarpus, Dryobalanops and Shorea) and five species belonging to the Moraceae, Myrtaceae, Celastraceae and Sapotaceae were investigated. In a tropical lowland dipterocarp forest in Sarawak, Malaysia, these trees produces seeds irregularly by intensely during general flowering and seeding events in 1996 and/or 1998. Dipterocarp seeds were preyed on by 51 insect species (11 families), which were roughly classified into three taxonomic groups: smaller moths (Trotricidae, Pyralidae, Crambidae, Immidae, Sesiidae, and Cosmopterigidae), scolytids (Scolydae) and weevils (Curdulionidae, Apionidae, Anthribidae, and Attelabidae). Although the host-specificity of invertebrate seed predators has been assumed to be high in tropical forests, it was found that the diet ranges of some insect predators were relatively wide and overlapped one another. Most seed predators that were collected in both study years changes their diets between general flowering and seeding events. The results of cluster analyses based on the number of adult of each predator species that emerged from 100 seeds of each tree species, suggested that the dominant species was not consistent, alternating between the two years.

Combination effect of adenovirus-mediated pro-apoptotic bax gene transfer with cisplatin or paclitaxel treatment in ovarian cancer cell lines

To develop a novel therapeutic strategy for ovarian cancer, we constructed a recombinant adenovirus which highly expresses pro-apoptotic Bax protein and examined its therapeutic effect on a series of ovarian cancer cell lines: A2780, A2780/cDDP, OVCAR-3 and SK-OV-3. A recombinant adenovirus carrying the Bax-alpha gene (AxCALNKYbax) induced high expression of the Bax-alpha protein in all the cell lines. The cytotoxic effect of Bax was observed in three ovarian cancer cell lines: the per cent reduction in the number of cells was 40.0% for cisplatin-sensitive A2780, 50.0% for cisplatin-resistant A2780/cDDP, and 64.8% for marginally cisplatin-resistant OVCAR-3. In contrast, it was only 12.3% for cisplatin-resistant SK-OV-3. Cisplatin-resistant A2780/cDDP had a p53 mutation and exhibited attenuated Bax induction after cisplatin treatment, which may explain why supplementation of Bax was effective in this chemoresistant ovarian cancer. Combination with cisplatin or paclitaxel enhanced the cytotoxic effect of Bax induction in all but one cell line including cisplatin-resistant A2780/cDDP. It appears that adenovirus-mediated Bax induction, with or without combination with conventional chemotherapy, useful strategy for the treatment of ovarian cancer.

Plant reproductive phenology over four years including an episode of general flowering in a lowland dipterocarp forest,Sarawak, Malaysia

The first systematic observation of a general flowering, a phenomenon unique to lowland mixed-dipterocarp forests in Southeast Asia, is presented. During general flowering, which occurs at irregular intervals of 3-10 yr, nearly all dipterocarp species together with species of other families come heavily into flower. We monitored reproductive phenology of 576 individual plants representing 305 species in 56 families in Sarawak, Malaysia. Observations continued for 53 mo from August 1992 and covered one episode of a general flowering cycle. Among 527 effective reproductive events during 43 mo, 57% were concentrated in the general flowering period (GFP) of 10 mo in 1996. We classified 257 species into flowering types based on timing and frequency of flowering. The most abundant type was "general flowering" (35%), which flowered only during GFP. The others were "supra-annual" (19%), "annual" (13%), and "sub-annual" (5%) types. General flowering type and temporal aggregation in reproductive events were commonly found among species in various categories of taxonomic groups, life forms, pollination systems, and fruit types. Possible causes for general flowering, such as promotion of pollination brought about by interspecific synchronization and paucity of climatic cues suitable for flowering trigger, are proposed, in addition to the predator satiation hypothesis of Janzen (1974).

Prognostic significance of heat shock proteins HSP70 and HSP90 in endometrial carcinomas

Heat shock proteins HSP70 and HSP90 are sex steroid receptor-associated proteins, and HSP90 expression has reportedly been correlated with sex steroid receptor status in endometrial carcinomas. HSP70 is also known to associate with several oncogene products such as p53 protein, and expression of HSP70 has been reported to be a prognostic factor in several malignant neoplasms. In endometrial carcinomas, however, little is known about the prognostic significance of these proteins. Therefore, we analyzed the survival of 44 endometrial carcinoma patients treated in our hospital with reference to the immunohistochemical expressions of HSP70 and HSP90, as well as the clinicopathological factors such as age, menstrual status, FIGO stage, histologic grade, p53 protein overexpression, and sex steroid receptor status. The expression of HSP70 was observed in 50% (22 cases), and strong HSP90 expression in 30% (13 cases) of the 44 carcinomas. The patients with HSP70-positive tumors showed significantly poorer survival than the patients with HSP70-negative tumors (p = 0.045), although multivariate analysis did not reveal HSP70 expression to be an independent prognostic factor. In contrast, the strong expression of HSP90 in the tumor was significantly correlated with a favorable prognosis of the patient (p = 0.026). Other prognostic indicators were FIGO stage (p = 0.0086) and the expression of progesterone receptor (p = 0.042). Accordingly, expressions of HSP70 and HSP90 each have different prognostic significance in endometrial carcinoma and may be useful for prediction of patient survival.

Human chorionic gonadotropin (hCG) inhibits cisplatin-induced apoptosis in ovarian cancer cells: possible role of up-regulation of insulin-like growth factor-1 by hCG

Gonadotropins have been suggested to play a role in the development or progression of ovarian cancer, and we have previously reported the expression of luteinizing hormone/ human chorionic gonadotropin (LH/hCG) receptor in 40% of epithelial ovarian carcinomas. To examine the biological effect of LH/hCG on ovarian cancer cells, apoptosis induced by cisplatin with or without hCG treatment was investigated in 2 ovarian cancer cell lines, OVCAR-3 and SK-OV-3. Stimulation of cell proliferation by hCG was also studied. In addition, to analyze further the mechanism of hCG signaling involved in apoptosis-inhibition, we examined the expression of LH/hCG receptors and the regulation by hCG for apoptosis-inhibitory pathways, such as the bcl-2/bax system and the insulin-like growth factor-1 (IGF-1)/IGF-1 receptor (IGFR) system. hCG did not increase cell proliferation in either cell line. However, hCG treatment suppressed cisplatin-induced apoptosis by 58% in the OVCAR-3 cells, as shown by immunofluorescent staining and quantitation of DNA fragmentation. LH/hCG receptor mRNA was expressed only in OVCAR-3, and no apoptosis-inhibitory effect of hCG was observed in the SK-OV-3 cells that did not express the receptor. In the OVCAR-3 cells, hCG significantly increased mRNA expression of IGF-1, but did not change mRNA levels of bcl-2/bax. Our findings suggest that LH/hCG influences the chemosensitivity of ovarian cancer cells through an apoptosis-inhibitory signal possibly via up-regulation of IGF-1 expression.

Expression of abnormal transcripts of the FHIT (fragile histidine triad) gene in ovarian carcinoma

To elucidate the role of the FHIT (fragile histidine triad) gene in ovarian carcinogenesis, the expression of the gene was analysed by reverse transcription-polymerase chain reaction (RT-PCR) in 51 cases of ovarian carcinoma, 6 cases of borderline tumour and 4 cases of benign ovarian tumour. The concomitant expressions of normal and abnormal FHIT transcripts were detected in 39% of carcinomas and in 83% of borderline tumours, while benign tumours and normal ovarian tissues expressed only normal transcript. In addition, there were 4 (8%) cases of carcinoma lacking expression of normal FHIT transcript, all of which were in advanced stages (stage III-IV) and poorly differentiated. These results suggest that the expression of abnormal transcripts of the FHIT gene is a feature of ovarian malignant/borderline tumours and that the complete loss of normal FHIT expression is related to the progression of ovarian carcinoma in a subset of the cases. However, abnormal FHIT transcripts themselves were not associated with any clinicopathological parameters, such as clinical stage, histological subtype of tumour, grade of differentiation or outcome of the patient. Additionally, abnormal FHIT expression was not associated with the presence of loss of heterozygosity (LOH) at this locus, suggesting that abnormal FHIT transcripts are not derived from genetic alteration or that genetic alteration at this locus is complicated.

Early invasive adenocarcinoma of the fallopian tube: a case report and review of the literature

We present an early invasive adenocarcinoma of the fallopian tube, which was incidentally found in a 45-year-old woman undergoing a laparotomy for uterine myoma. Histological examination of the hydropic tubes revealed widespread endosalpingeal hyperplasia without atypia in both tubes. In addition, the left tube contained 3 scattered lesions of carcinoma in situ, one of which was accompanied by a microfocus of definite stromal invasion confined within the endosalpingeal mucosa. Such a case seems extremely rare, and it might represent the histological appearance of an early invasive feature of tubal carcinoma. We reviewed previously reported cases of in situ and/or early invasive carcinomas of the fallopian tube with respect to the pathological diagnosis and histogenesis of primary tubal adenocarcinomas.

Expression of vascular endothelial growth factor (VEGF) during folliculogenesis and corpus luteum formation in the human ovary

Vascular endothelial growth factor (VEGF) has been suggested to be involved in angiogenesis and microvascular hyperpermeability. We examined immunohistochemically the expression of VEGF in the granulosa and theca cells, along with that of proliferating cell nuclear antigen (PCNA), in the vascular endothelium during the course of follicular development and corpora lutea formation in human ovaries. The immunolocalization of VEGF in these cells was compared with that of another putative angiogenic factor, basic fibroblast growth factor (bFGF). The granulosa cells in the primordial and primary follicles were VEGF negative, but at the preantral stage, the granulosa cells showed weakly positive immunostaining for VEGF. However, the VEGF immunostaining in the granulosa cells was weak throughout the folliculogenesis. In contrast, the theca interna cells of developing follicles showed strong staining for VEGF, which was well correlated with the PCNA positivity in the vascular endothelial cells in the thecal layer. In the atretic follicles, the granulosa and theca cells were VEGF negative. In the corpora lutea, VEGF was strongly expressed in both granulosa and theca lutein cells in the early luteal phase when the PCNA positivity in the endothelium increased, but the VEGF staining in these cells became weak in the mid- and late luteal phases. Accordingly, the PCNA positivity in the vascular endothelium was well correlated with the expression of VEGF in the theca cells during follicular development and atresia, and that in the granulosa and theca lutein cells in corpora lutea formation and regression. In addition, the immunolocalization of VEGF was different from that of bFGF.

Stability of mitomycin admixtures

The stability of mitomycin in admixtures for continuous intravenous infusion was studied. Mitomycin was reconstituted and diluted to 50 micrograms/mL in polyvinyl chloride minibags containing 5% dextrose injection 50 mL or 0.9% sodium chloride injection 50 mL. Additional mitomycin admixtures were reconstituted with a buffer solution containing monobasic and dibasic sodium phosphate; these were diluted with 5% dextrose injection only. Admixtures were stored at room temperature (27-30 degrees C) and refrigerated temperature (5 degrees C) for 120 days. Mitomycin concentrations in each admixture were tested by high-performance liquid chromatography (HPLC) immediately after admixture and at intervals during storage. Ultraviolet spectra were determined at the same time as HPLC analysis, and the admixtures were visually inspected and tested for pH. Mitomycin concentrations decreased rapidly in the unbuffered admixtures; after 12 hours at room temperature, less than 26% of the drug remained in the dextrose admixture. When the unbuffered admixtures were refrigerated for 12 hours, the mitomycin concentrations decreased 10% in the sodium chloride admixtures and 33% in the dextrose admixtures; after 24 hours, the percentages of drug loss were 23% and 42%, respectively. Mitomycin concentrations in the buffered admixtures showed no substantial decrease during 120 days at 5 degrees C. At room temperature, concentrations decreased 10% after 15 days. When the admixture is buffered to a pH of approximately 7.8, mitomycin is stable in 5% dextrose injection for up to 15 days at room temperature and at least 120 days at 5 degrees C. Unbuffered mitomycin admixtures should not be stored or administered by prolonged i.v. infusion.

Drug concentration errors related to sampling from Silastic catheters

To the Editor:

Constant infusion of some antitumor agents appears to improve their efficacy and/or diminish adverse effects associated with their administration. Silastic catheters placed for long-term central access facilitate this type of therapy. Also, they provide a means to obtain blood with minimal trauma for the patient. During treatment it is sometimes useful to withdraw samples for assay of drug blood levels. When doing so, we became concerned about unusually high 5-fluorouracil (5-FU) values in several patients, causing us to measure drug concentration in samples taken simultaneously from the catheter and a peripheral vein. Catheter samples showed seven to 80 times greater concentration of 5-FU. In one individual who had been off infusion for three days, a small 5-FU concentration persisted in the catheter sample whereas the peripheral vein value was zero as expected.

Subsequently, we performed an in vitro study. A Broviac catheter (volume, 0.6 mL) was perfused for five days at 2.0 mL per hour with a solution containing 500 mg 5-FU made up to 60 mL with 0.9% saline. The catheter then was flushed with 30-mL water to remove all fluid containing 5-FU. Ensuing sampling and flushing was done in accordance with Table 1. The last milliliter of flush solution was analyzed in each instance by high-pressure liquid chromatography technology.

Since all of the 5-FU infusion solution had been removed, the presence of drug in the water wash indicates that 5-FU was passing into the catheter lumen from the silastic wall.

We believe it is important to recognize that other drugs may act in the same way. The use of silastic catheters for both infusion and sampling may lead to an overestimation of drug concentration even though sufficient blood is withdrawn before taking the definitive sample.

Please see the PDF for Table.