Cytotoxic chemotherapy in the contemporary management of metastatic castration-resistant prostate cancer (mCRPC)

Coronaphobia: A barrier to ongoing cancer treatment?

Introduction

Increased stress levels caused by the pandemic might cause delays in cancer treatment. We conducted a survey among cancer patients undergoing treatment to evaluate their psychological wellbeing and treatment adherence during Coronavirus disease 19 (COVID‐19) pandemic.

Material and Methods

Patients receiving active chemotherapy at a private oncology center between January and May 2021 were included. Healthy volunteers were employees of a district health directorate with no history of cancer or chronic disease. Treatment adherence was described as compliant if the prescribed treatment was received within a week and the information was gained from patient charts. Hospital anxiety and depression scale (HADS) and COVID‐19 phobia scale (CP19‐S) were administered to participants.

Results

402 participants were included; 193 (48%) were cancer patients. The mean age of the participants was 44 years old and 68% of the participants were female. All participants' CP19‐S mean score was 47.9. Patient group had significantly lower CP19‐S (p = 0.006). Chronic disease and history of a shocking event were the factors associated with CP19‐S. All participants reporting hospital anxiety were found to have significantly higher COVID‐19 phobia levels (p < 0.05). Patients' mean HADS‐anxiety score was significantly higher (7.3 vs. 6.5, p = 0.027). COVID‐19 phobia was an independent factor increasing the level of anxiety and depression in both groups. Adherence to treatment was 100%.

Conclusion

The pandemic increased levels of anxiety, however, cancer treatment continued to be a priority in patients' lives. Strategies should be developed to support oncology patients cope with the pandemic and increase their courage to avoid treatment delays.

The long non-coding RNA GHSROS reprograms prostate cancer cell lines toward a more aggressive phenotype

It is now appreciated that long non-coding RNAs (lncRNAs) are important players in orchestrating cancer progression. In this study we characterized GHSROS, a human lncRNA gene on the opposite DNA strand (antisense) to the ghrelin receptor gene, in prostate cancer. The lncRNA was upregulated by prostate tumors from different clinical datasets. Transcriptome data revealed that GHSROS alters the expression of cancer-associated genes. Functional analyses in vitro showed that GHSROS mediates tumor growth, migration and survival, and resistance to the cytotoxic drug docetaxel. Increased cellular proliferation of GHSROS-overexpressing PC3, DU145, and LNCaP prostate cancer cell lines in vitro was recapitulated in a subcutaneous xenograft model. Conversely, in vitro antisense oligonucleotide inhibition of the lncRNA reciprocally regulated cell growth and migration, and gene expression. Notably, GHSROS modulates the expression of PPP2R2C, the loss of which may drive androgen receptor pathway-independent prostate tumor progression in a subset of prostate cancers. Collectively, our findings suggest that GHSROS can reprogram prostate cancer cells toward a more aggressive phenotype and that this lncRNA may represent a potential therapeutic target.

Evaluations of CRC2631 toxicity, tumor colonization, and genetic stability in the TRAMP prostate cancer model

Conventional cancer chemotherapies are not fully efficacious and do not target tumors, leading to significant treatment-related morbidities. A number of genetically attenuated cancer-targeting bacteria are being developed to safely target tumors in vivo. Here we report the toxicological, tumor-targeting, and efficacy profiles of Salmonella enterica serovar Typhimurium CRC2631 in a syngeneic and autochthonous TRAMP model of aggressive prostate cancer. CRC2631 preferentially colonize primary and metastatic tumors in the TRAMP animals. In addition, longitudinal whole genome sequencing studies of CRC2631 recovered from prostate tumor tissues demonstrate that CRC2631 is genetically stable. Moreover, tumor-targeted CRC2631 generates an anti-tumor immune response. Combination of CRC2631 with checkpoint blockade reduces metastasis burden. Collectively, these findings demonstrate a potential for CRC2631 in cancer immunotherapy strategies.

How does COVID-19 fear and anxiety affect chemotherapy adherence in patients with cancer

Aim: To investigate how COVID-19 fear and anxiety (COV-FA) affects chemotherapy adherence in patients with cancer. Materials & methods: The records of 3661 patients with chemotherapy (CT) appointments were retrospectively reviewed. Results: The CT postponement rates before and after COVID-19 were 11.6% and 14.2%, respectively (p = 0.017). The rate of COV-FA-related CT postponement after telemedicine was lower than that before (4.6% vs 17.4%, p = 0.012). The median time to come back to treatment of the COV-FA group was 47 days (range 19–72 days). Advanced age (≥60 years) was found to be the independent factor that was predictive of time to come back to treatment (p = 0.043). Conclusion: The CT postponement rate increased after COVID-19. COV-FA-related CT postponement decreased after telemedicine. Advanced age could be predictive of time to come back to treatment.

Impact of the introduction of novel hormonal agents on metastatic castration-resistant prostate cancer treatment choice

BACKGROUND

Docetaxel-based chemotherapy has been the cornerstone of the management of symptomatic metastatic castration-resistant prostate cancer (mCRPC) since 2004. This study aimed to describe how real-world clinical practice was changed with the public funding of novel hormonal agents (abiraterone and enzalutamide) in Quebec.

METHODS

We conducted a retrospective cohort study in two McGill University hospitals. Hospital-based cancer registries were used to select mCRPC patients in medical oncology departments from January 2010 to June 2014. Two groups according to mCRPC diagnosis year were built, with 2012 chosen as the cut-off year, corresponding to the year abiraterone was approved for public reimbursement in second-line in Quebec. Kaplan-Meier analysis was used to estimate time to first docetaxel prescription since mCRPC diagnosis before and after 2012. Cox regression was used to identify predictive factors of docetaxel and novel hormonal agent use.

RESULTS

In our cohort, 308 patients diagnosed with mCRPC were selected with 162 patients in the pre-2012 group and 146 patients in the post-2012 group. The median age at mCRPC was 74.0 years old. At 12 months from diagnosis, 69% of patients received a prescription for docetaxel in the pre-2012 group comparatively to 53% in the post-2012 group. Factors that decreased the likelihood of docetaxel utilization were: age older than 80 at mCRPC diagnosis (HR: 0.5; 95%CI: 0.3-0.7), mCRPC diagnosis after 2012 (HR: 0.6; 95%CI: 0.4-0.8), and asymptomatic disease at mCRPC diagnosis (HR: 0.5; 95%CI: 0.3-0.7).

CONCLUSION

The introduction of novel hormonal agents reduced first-line and overall docetaxel utilization and delayed time to its initiation.

Targeting the stress oncoprotein LEDGF/p75 to sensitize chemoresistant prostate cancer cells to taxanes

Prostate cancer (PCa) is associated with chronic prostate inflammation resulting in activation of stress and pro-survival pathways that contribute to disease progression and chemoresistance. The stress oncoprotein lens epithelium-derived growth factor p75 (LEDGF/p75), also known as DFS70 autoantigen, promotes cellular survival against environmental stressors, including oxidative stress, radiation, and cytotoxic drugs. Furthermore, LEDGF/p75 overexpression in PCa and other cancers has been associated with features of tumor aggressiveness, including resistance to cell death and chemotherapy. We report here that the endogenous levels of LEDGF/p75 are upregulated in metastatic castration resistant prostate cancer (mCRPC) cells selected for resistance to the taxane drug docetaxel (DTX). These cells also showed resistance to the taxanes cabazitaxel (CBZ) and paclitaxel (PTX), but not to the classical inducer of apoptosis TRAIL. Silencing LEDGF/p75 effectively sensitized taxane-resistant PC3 and DU145 cells to DTX and CBZ, as evidenced by a significant decrease in their clonogenic potential. While TRAIL induced apoptotic blebbing, caspase-3 processing, and apoptotic LEDGF/p75 cleavage, which leads to its inactivation, in both taxane-resistant and -sensitive PC3 and DU145 cells, treatment with DTX and CBZ failed to robustly induce these signature apoptotic events. These observations suggested that taxanes induce both caspase-dependent and -independent cell death in mCRPC cells, and that maintaining the structural integrity of LEDGF/p75 is critical for its role in promoting taxane-resistance. Our results further establish LEDGF/p75 as a stress oncoprotein that plays an important role in taxane-resistance in mCRPC cells, possibly by antagonizing drug-induced caspase-independent cell death.

Current treatment strategies for advanced prostate cancer

During the past decade, treatment strategies for patients with advanced prostate cancer involving stage IV (T4N0M0, N1M0 or M1) hormone-sensitive prostate cancer and recurrent prostate cancer after treatment with curative intent, as well as castration-resistant prostate cancer, have extensively evolved with the introduction and approval of several new agents including sipuleucel-T, radium-223, abiraterone, enzalutamide and cabazitaxel, all of which have shown significant improvement on overall survival. The appropriate use of these agents and the proper sequencing of these agents are still not optimized. The results of several recently reported randomized controlled trials and retrospective studies could assist in developing a treatment strategy for advanced prostate cancer. In addition, prospective studies and molecular characterization of tumors to address these issues are ongoing.

Therapy decisions for the symptomatic patient with metastatic castration-resistant prostate cancer

Metastatic prostate cancer continues to kill approximately 30,000 men per year. Since 2010, five new therapeutic agents have been Food and Drug Administration (FDA) approved to treat metastatic castration-resistant prostate cancer (mCRPC). With the increasing number of therapies available to clinicians, the most effective sequence in which to implement these treatments remains unknown. The presence or absence of symptoms (i.e., bony pain, visceral crisis) is a key parameter that informs the decision-making process regarding therapy. Treatment algorithms based on: 1) asymptomatic/minimal symptoms, 2) moderate symptoms or chemotherapy ineligible or 3) symptomatic disease need to be developed.