Chemotherapy with or without estramustine for treatment of castration-resistant prostate cancer: A systematic review and meta-analysis

Gösta Jönsson (1909-1978): A pioneer in the hormonal treatment of prostate cancer in Sweden

Treatment of castration-resistant prostate cancer is and has been a challenge. In 1957, the chemist Imre Könyves came to Sweden as a refugee from Hungary and started to work at AB Leo, a pharmaceutical company in Helsingborg. In 1961, he started to synthesize compounds where the oestrogens were linked to a mustard group by a carbamate. This resulted in estramustine phosphate, which was initially tested against mammary cancer with disappointing results. He then started a cooperation with urology professor Gösta Jönsson, Head of the Department of Urology at the Lund University Hospital, to test estramustine phosphate against prostate cancer. Jönsson started clinical estramustine phosphate tests in 1966. His studies were one-armed and consecutive, with a "favourable response" in 83% of previously untreated patients. These favourable results could not be reproduced in later randomized controlled studies suggesting that estramustine phosphate as primary treatment was not better than conventional estrogenic treatment. Conclusions: Even if the results of Gösta Jönsson's studies could not be confirmed, the subsequent randomized studies of estramustine phosphate may hide the desired action of estramustine phosphate in a subgroup of patients. It has still not been elucidated whether estramustine phosphate has effects in this subgroup of patients with ostrogen-resistant prostate cancer.

The past and present of prostate cancer and its treatment and diagnostics: A historical review

The prognosis of local prostate cancer has improved drastically during the past 60 years. Similarly, the prognosis in metastatic stage is constantly improving due to a number of new pharmaceuticals introduced over the past 10 years. Previously, only palliative treatments were available for prostate cancer, but today, there are multiple options for treatment with curative intent: robotic-assisted radical prostatectomy, stereotactic radiotherapy and brachytherapy. Additionally, life-prolonging chemotherapeutic and androgen-suppressive treatments, as well as diagnostic imaging and staging, have improved considerably. This review summarizes the history of the treatment and diagnostics of prostate cancer, with a focus on the past 60 years. The aim was to provide a concise and easy-to-read introduction on the matter for all people that work with prostate cancer, as well as for patients. The literature was thoroughly examined covering the period from the earliest traceable records to the latest state-of-the-art studies.

Potent and Selective Benzothiazole-Based Antimitotics with Improved Water Solubility: Design, Synthesis, and Evaluation as Novel Anticancer Agents

The design of colchicine site ligands on tubulin has proven to be a successful strategy to develop potent antiproliferative drugs against cancer cells. However, the structural requirements of the binding site endow the ligands with low aqueous solubility. In this work, the benzothiazole scaffold is used to design, synthesize, and evaluate a new family of colchicine site ligands exhibiting high water solubility. The compounds exerted antiproliferative activity against several human cancer cell lines, due to tubulin polymerization inhibition, showing high selectivity toward cancer cells in comparison with non-tumoral HEK-293 cells, as evidenced by MTT and LDH assays. The most potent derivatives, containing a pyridine moiety and ethylurea or formamide functionalities, displayed IC₅₀ values in the nanomolar range even in the difficult-to-treat glioblastoma cells. Flow cytometry experiments on HeLa, MCF7, and U87MG cells showed that they arrest the cell cycle at the G2/M phases at an early time point (24 h), followed by apoptotic cell death 72 h after the treatment. Tubulin binding was confirmed by microtubule network disruption observed via confocal microscopy. Docking studies support favorable interaction of the synthesized ligands at the colchicine binding site. These results validate the proposed strategy to develop potent anticancer colchicine ligands with improved water solubility.

NO-HDAC dual inhibitors

HDAC inhibitors and NO donors have both demonstrated independently broad therapeutic potential in a variety of diseases. Borretto et al. presented the topic of NO-HDAC dual inhibitors for the first time in 2013 as an attractive new topic. Here we collected the general structure of all synthesized NO-HDAC dual inhibitors, lead compounds, synthesis methods and biological features of the most potent dual NO-HDAC inhibitor in each category with the intention of assisting in the synthesis and optimization of new drug-like compounds for diverse diseases. Based on studies done so far, NO-HDAC dual inhibitors have displayed satisfactory results against wound healing (3), heart hypertrophy (3), inflammatory, cardiovascular, neuromuscular illnesses (11a-11e) and cancer (6a-6o, 9a-9d, 10a-10d, 16 and 17). NO-HDAC dual inhibitors can have high therapeutic potential for various diseases due to their new properties, NO properties, HDAC inhibitor properties and also due to the effects of NO on HDAC enzymes.

Immunotherapy as a Precision Medicine Tool for the Treatment of Prostate Cancer

Prostate cancer (PCa) is the most frequently diagnosed type of cancer among Caucasian males over the age of 60 and is characterized by remarkable heterogeneity and clinical behavior, ranging from decades of indolence to highly lethal disease. Despite the significant progress in PCa systemic therapy, therapeutic response is usually transient, and invasive disease is associated with high mortality rates. Immunotherapy has emerged as an efficacious and non-toxic treatment alternative that perfectly fits the rationale of precision medicine, as it aims to treat patients on the basis of patient-specific, immune-targeted molecular traits, so as to achieve the maximum clinical benefit. Antibodies acting as immune checkpoint inhibitors and vaccines entailing tumor-specific antigens seem to be the most promising immunotherapeutic strategies in offering a significant survival advantage. Even though patients with localized disease and favorable prognostic characteristics seem to be the ones that markedly benefit from such interventions, there is substantial evidence to suggest that the survival benefit may also be extended to patients with more advanced disease. The identification of biomarkers that can be immunologically targeted in patients with disease progression is potentially amenable in this process and in achieving significant advances in the decision for precision treatment of PCa.

Synthetically modified methoxsalen for enhanced cytotoxicity in light and dark reactions

Linear furocoumarins, also known as psoralens, are clinically useful photo-activated pharmaceuticals employed to address hyperproliferative skin diseases. Seven diverse cytotoxic pharmacophores have been synthetically attached to 8-methoxypsoralen via a 5-amino functionality. The resulting unique set of compounds was evaluated for dark and light toxicity against PAM212 keratinocytes in culture.

Radical Prostatectomy With and Without Neoadjuvant Chemohormonal Pretreatment for High-Risk Localized Prostate Cancer: A Comparative Propensity Score Matched Analysis

BACKGROUND

To investigate the clinical outcomes in patients with high-risk prostate cancer (PCa) treated with neoadjuvant chemohormonal therapy (NCHT) before radical prostatectomy (RP).

PATIENTS AND METHODS

Our NCHT protocol involved complete androgen blockade followed by 6 cycles of docetaxel (30 mg/m²) plus estramustine phosphate (560 mg). NCHT was provided to 60 patients with PCa before RP, and we compared the clinical and pathologic outcomes with those of 349 patients with high-risk PCa who underwent RP alone using propensity score matching. The data for those who underwent RP alone were obtained from the Michinoku Japan Urological Cancer Study Group database.

RESULTS

In the NCHT group, 10.0% experienced pathologic complete response, 3.3% had positive surgical margins, and 13.3% developed severe complications (Clavien-Dindo grade III or higher) after RP. The median follow-up duration was 42.5 months, and the 5-year biochemical recurrence (BCR)-free survival was 60.1%. In multivariate analysis, pN+ was an independent prognostic factor for BCR (hazard ratio = 5.251, 95%CI 1.300-21.201; P = .020). In propensity score matching, the BCR rate in the NCHT group was significantly lower than that in the RP alone group (P = .021). In subgroup analyses, the BCR rate in patients with a single high-risk factor was significantly lower in the NCHT group than in the RP-alone group (P = .027).

CONCLUSION

NCHT before RP can reduce the risk of BCR in patients with high-risk PCa, particularly if a single high-risk factor is present. However, the potential for perioperative complications should be considered.

The efficacy and safety comparison of docetaxel, cabazitaxel, estramustine, and mitoxantrone for castration-resistant prostate cancer: A network meta-analysis

AIMS

The aim of this study was to compare the efficacy and safety of docetaxel, cabazitaxel, docetaxel + estramustine, mitoxantrone in the management of castration-resistant prostate cancer (CRPC).

METHODS

Electronic databases including PubMed, Cochrance Library and Embase were searched for studies published from when the databases were established to January 1st, 2018. Randomized controlled trials (RCTs) that compared docetaxel + prednisone (DP), cabazitaxel + prednisone (CP), docetaxel + estramustine + prednisone (DEP), and mitoxantrone + cabazitaxel + prednisone (MP) for CRPC treatment were identified. The network meta-analysis was conducted with software R 3.3.2. We analyzed the main outcomes, including the overall survival (OS), progression-free survival (PFS), prostate-specific antigen (PSA) response, tumor response and severe adverse events (AEs). Ranking of the chemotherapeutic agents was based on probabilities of interventions for each of the outcomes that were performed. The consistency of direct and indirect evidence was assessed by node splitting.

RESULTS

10 RCTs, with 3590 patients, were analyzed. The network meta-analysis results revealed that CP significantly increased OS, PFS, PSA response, tumor response, and severe AEs compared to MP. DP showed similar results with CP except for tumor response, where it showed slight inferiority in effectiveness. DEP was associated with clearly improved outcomes in PFS, PSA response and tumor response compared to those of MP, but this was not the case for OS benefit and severe AEs. No significant difference was detected in DP, CP and DEP except for the outcomes of severe AEs. MP was less effective in survival and clinical benefit, but much safer in safety outcomes than other chemotherapy agents. The probabilities of rank plots showed that CP ranked first in OS and tumor response; DEP ranked first in PFS time and PSA response; MP was the best treatment mode for safety.

CONCLUSIONS

DP and CP survival benefit (OS, PFS) and clinical benefit (PSA response and tumor response) were comparable, as well as their associated AEs. DEP was associated with less survival benefit, similar clinical improvement and more AEs than DP or CP. MP had the lowest survival and clinical benefit but excellent safety than other agents. Based on evidences of current results, we recommended CP as the most suitable chemotherapy agent for CRPC patients, followed by DP, MP as third, and DEP as the last choice. However, considering limitations of our network meta-analysis, additional high-quality studies are needed for further evaluation.

Circulating tumor DNA in blood: Future genomic biomarkers for cancer detection

Cancer is characterized by Darwinian evolution and is a primary cause of mortality and morbidity around the globe. Over the preceding decade, the treatment of cancer has been markedly improved by many targeted therapies, but these treatments have given birth to new challenges and issues. Clonal evolution and tumor heterogeneity present a significant challenge in designing cancer therapies. Fortunately, these restrictions have been overcome by technological advancements allowing us to track both genetic and epigenetic aberrations. Cell-free circulating tumor DNA (ctDNA) analysis, or "liquid biopsy" from a blood sample, provides the opportunity to track the genetic landscape of cancerous lesions. This review focuses on ctDNA analysis as a noninvasive method and versatile biomarker for cancer treatment and technological advancements for ctDNA analysis. This method may able to cope with all the challenges associated with previous cancer therapies and has the potential to monitor minimal residual disease, tumor burden, and therapy response and provide rapid detection of relapse. However, there are many challenges that still need to be addressed. Future prognosis, diagnosis, and analysis of ctDNA require reproducibility and accuracy of results, which are not possible without the validation and optimization of procedures. Integrated digital error suppression has thus far shown promise in the detection of ctDNA in cancer.