First-line non-cytotoxic therapy in chemotherapy-naive patients with metastatic castration-resistant prostate cancer: a systematic review of 10 randomised clinical trials

AICAR Induces Apoptosis and Inhibits Migration and Invasion in Prostate Cancer Cells Through an AMPK/mTOR-Dependent Pathway

Current clinical challenges of prostate cancer management are to restrict tumor growth and prohibit metastasis. AICAR (5-aminoimidazole-4-carbox-amide-1-β-d-ribofuranoside), an AMP-activated protein kinase (AMPK) agonist, has demonstrated antitumor activities for several types of cancers. However, the activity of AICAR on the cell growth and metastasis of prostate cancer has not been extensively studied. Herein we examine the effects of AICAR on the cell growth and metastasis of prostate cancer cells. Cell growth was performed by MTT assay and soft agar assay; cell apoptosis was examined by Annexin V/propidium iodide (PI) staining and poly ADP ribose polymerase (PARP) cleavage western blot, while cell migration and invasion were evaluated by wound-healing assay and transwell assay respectively. Epithelial–mesenchymal transition (EMT)-related protein expression and AMPK/mTOR-dependent signaling axis were analyzed by western blot. In addition, we also tested the effect of AICAR on the chemosensitivity to docetaxel using MTT assay. Our results indicated that AICAR inhibits cell growth in prostate cancer cells, but not in non-cancerous prostate cells. In addition, our results demonstrated that AICAR induces apoptosis, attenuates transforming growth factor (TGF)-β-induced cell migration, invasion and EMT-related protein expression, and enhances the chemosensitivity to docetaxel in prostate cancer cells through regulating the AMPK/mTOR-dependent pathway. These findings support AICAR as a potential therapeutic agent for the treatment of prostate cancer.

Network Pharmacology-Based identification of pharmacological mechanism of SQFZ injection in combination with Docetaxel on lung cancer

Docetaxel is the widely-used first-line therapy to treat lung cancer around the world. However, tumor progression and severe side effect occurred in some patients with docetaxel treatment. Most of the side effects were caused by immunocompromise, which limits the long-term use of docetaxel. Shenqi Fuzheng (SQFZ) injection has been used as adjuvant therapy to treat lung cancer which may enhance immunity as well. Owing to the complexity of drug combination, the mechanism of SQFZ injection in combination with docetaxel on lung cancer remains unclear. Therefore, a network pharmacology-based strategy was proposed in this study to help solve this problem. Network pharmacology approach comprising multiple components, candidate targets of component and therapeutic targets, has been used in this study. Also, in vivo and in vitro experiment was applied to verify the predicted targets from network pharmacology We established mouse lung cancer model and inject with docetaxel and SQFZ injection. Tumour weight, spleen index, thymus index, immunohistochemical staining and ELISA were conducted to evaluate the effect and underlying mechanisms of docetaxel and SQFZ injection. Besides A549 cells were also administrated by docetaxel and SQFZ.The indexes BCL2, CASP3 and CASP9 were determined after administration. The results indicated that combination of SQFZ and docetaxel could reduce tumour weight, enhance the spleen index, thymus index. Meanwhile, it could improve the activity of caspase-3 and IL-2 in mice and caspase-3, caspase-9 in A549 cell and inhibit the activity of BCL-2 in A549 cell, which verified the potential protective targets predicted by network pharmacology. In conclusion, combination of SQFZ and docetaxel could increase the curative effect by inducing tumour to apoptosis and play a key role on immunoprotection to reduce side effects.

Timing of androgen deprivation monotherapy and combined treatments in castration-sensitive and castration-resistant prostate cancer: a narrative review

PURPOSE

Standard androgen deprivation therapy (ADT) can be initiated early at the time of diagnosis in asymptomatic castration-sensitive advanced prostate cancer. This definition has recently been expanded to also include an early combined treatment with standard ADT and new antihormonal drugs. We aimed to present the best available evidence for the timing of initiation of ADT monotherapy and combined treatments in castration-sensitive/-resistant prostate cancer.

METHODS

For this narrative review, we searched Cochrane reviews in the Cochrane Library, systematic reviews and randomized controlled trials in MEDLINE, phase III and ongoing trials in ClinicalTrials.gov and screened the reference lists to extract articles of interest. One author screened the references which were finally included after assessing their relevance through discussion with other experts in the field.

RESULTS

The identified references were grouped by medication (standard ADT, androgen biosynthesis inhibitor, androgen receptor antagonists or combined therapies) and tumor stage (castration sensitive or resistant). The evidence was narratively summarized and discussed in the context of the current therapeutic landscape.

CONCLUSIONS

Early standard ADT can reduce symptoms of disease progression and may extend progression-free and overall survival. The patient should be well informed about the higher rates of treatment-related side effects. Deferring standard ADT might be indicated only for well-informed or unfit patients. Early standard ADT is increasingly combined with new antihormonal drugs in castration-sensitive metastatic prostate cancer to gain additional survival and quality of life benefits. Combined treatment at the time of development of castration-resistant disease is well established.

Effectiveness and tolerability of targeted drugs for the treatment of metastatic castration-resistant prostate cancer: a network meta-analysis of randomized controlled trials

PURPOSE

Castration-resistant prostate cancer (CRPC) refers to prostate cancer that has progressed after initial androgen deprivation therapy (ADT). Over the years, treatment strategies for metastatic CRPC (mCRPC) have undergone considerable changes. We performed a network meta-analysis to assess the effectiveness and tolerability of targeted agents for mCRPC.

METHODS

We search databases including MEDLINE, EMBASE, and the Cochrane Library through Sep 5, 2017. The major effectiveness outcomes were progression-free survival (PFS) and overall survival (OS). The tolerability outcome was severe adverse events (AEs) of grade ≥ 3.

RESULTS

Twenty-six articles assessing a total of 20,314 patients were included in this study. A random-effect analysis showed that targeted agents could significant prolong PFS in mCRPC patients (I2 = 94.3%; hazard ratio (HR): 0.74; 95% confidence interval (CI): 0.65-0.84; p < 0.001). In addition, the surface under the cumulative ranking curve (SUCRA) ranking from the network analysis showed that enzalutamide was the most effective in improving the PFS of mCRPC patients (100%), followed by abiraterone (90.1%) and tasquinimod (84.2%). Additionally, targeted agents could clearly prolong OS in mCRPC patients (I2 = 71.6%; HR: 0.91; 95% CI: 0.85-0.97; p < 0.001). Furthermore, based on SUCRA ranking, enzalutamide was the most effective in improving the OS of mCRPC patients (97.2%), followed by abiraterone (91.1%) and zibotentan (65.8%). Intetumumab was associated with the lowest incidence of severe AEs (94.9%), followed by atrasentan (85.1%) and placebo (79.3%).

CONCLUSION

In patients with mCRPC, enzalutamide, abiraterone and tasquinimod can prolong PFS, and enzalutamide and abiraterone can prolong OS. Additionally, enzalutamide and abiraterone can improve both PFS and OS with a low risk of causing severe AEs.

Annual Report to the Nation on the Status of Cancer, part II: Recent changes in prostate cancer trends and disease characteristics

BACKGROUND

Temporal trends in prostate cancer incidence and death rates have been attributed to changing patterns of screening and improved treatment (mortality only), among other factors. This study evaluated contemporary national-level trends and their relations with prostate-specific antigen (PSA) testing prevalence and explored trends in incidence according to disease characteristics with stage-specific, delay-adjusted rates.

METHODS

Joinpoint regression was used to examine changes in delay-adjusted prostate cancer incidence rates from population-based US cancer registries from 2000 to 2014 by age categories, race, and disease characteristics, including stage, PSA, Gleason score, and clinical extension. In addition, the analysis included trends for prostate cancer mortality between 1975 and 2015 by race and the estimation of PSA testing prevalence between 1987 and 2005. The annual percent change was calculated for periods defined by significant trend change points.

RESULTS

For all age groups, overall prostate cancer incidence rates declined approximately 6.5% per year from 2007. However, the incidence of distant-stage disease increased from 2010 to 2014. The incidence of disease according to higher PSA levels or Gleason scores at diagnosis did not increase. After years of significant decline (from 1993 to 2013), the overall prostate cancer mortality trend stabilized from 2013 to 2015.

CONCLUSIONS

After a decline in PSA test usage, there has been an increased burden of late-stage disease, and the decline in prostate cancer mortality has leveled off. Cancer 2018;124:2801-2814. © 2018 American Cancer Society.

Third-line treatment and 177Lu-PSMA radioligand therapy of metastatic castration-resistant prostate cancer: a systematic review

AIMS

There is a controversy as to the relative efficacy of 177Lu prostate specific membrane antigen (PSMA) radioligand therapy (RLT) and third-line treatment for patients with metastatic castration-resistant prostate cancer (mCRPC). The aim of our systematic review was to elucidate whether 177Lu-PSMA RLT and third-line treatment have similar effects and adverse effects (PROSPERO ID CRD42017067743).

METHODS

The review followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Searches in Pubmed and Embase selected articles up to September 2017. A search in ClinicalTrials.gov indicated ongoing studies. The meta-analysis used the random-effects model.

RESULTS

Twelve studies including 669 patients reported 177Lu-PSMA RLT. Overall, 43% of the patients had a maximum decline of PSA of ≥50% following treatment with 177Lu-PSMA RLT. The treatment with 177Lu-PSMA-617 and 177Lu-PSMA for imaging and therapy (I&T) had mainly transient adverse effects. Sixteen studies including 1338 patients reported third-line treatment. Overall, 21% of the patients had a best decline of PSA of ≥50% following third-line treatment. After third-line treatment with enzalutamide and cabazitaxel, adverse effects caused discontinuation of treatment for 10% to 23% of the patients. 177Lu-PSMA RLT gave a best PSA decline ≥50% more often than third-line treatment (mean 44% versus 22%, p = 0.0002, t test). 177Lu-PSMA RLT gave objective remission more often than third-line treatment (overall 31 of 109 patients versus 43 of 275 patients, p = 0.004, χ2 test). Median survival was longer after 177Lu-PSMA RLT than after third-line treatment, but the difference was not statistically significant (mean 14 months versus 12 months, p = 0.32, t test). Adverse effects caused discontinuation of treatment more often for third-line treatment than for 177Lu-PSMA RLT (22 of 66 patients versus 0 of 469 patients, p < 0.001, χ2 test).

CONCLUSIONS

As for patients with mCRPC, treatment with 177Lu-PSMA-617 RTL and 177Lu-PSMA I&T gave better effects and caused fewer adverse effects than third-line treatment.

Transdermal administration of melatonin coupled to cryopass laser treatment as noninvasive therapy for prostate cancer

Melatonin, a pineal gland hormone, exerts oncostatic activity in several types of human cancer, including prostate, the most common neoplasia and the third most frequent cause of male cancer death in the developed world. The growth of androgen-sensitive LNCaP prostate cancer cells in mice is inhibited by 3 mg/kg/week melatonin (0.09 mg/mouse/week) delivered by i.p. injections, which is equivalent to a dose of 210 mg/week in humans. The aim of this study is to test an alternative noninvasive delivery route based on transdermal administration of melatonin onto the tumor area followed by cryopass-laser treatment. Two groups of immunodepressed mice were studied, one (n = 10) subjected to 18 cryopass-laser therapy sessions and one (n = 10) subjected to the same treatment without melatonin. These groups were compared with mice treated with i.p.-administered melatonin or vehicle with the same time schedule. We found that cryopass-laser treatment is as efficient as i.p. injections in reducing the growth of LNCaP tumor cells, affecting plasma melatonin and redox balance. Furthermore, both delivery routes share the same effects on the involved biochemical pathway driven by hypoxia-inducible factor 1α. However, cryopass-laser, as used in the present experimental setup, is less efficient than i.p delivery route in increasing the melatonin content and Nrf2 expression in the tumor mass. We conclude that cryopass-laser treatment may have impact for melatonin-based therapy of prostate cancer, by delivering drugs transdermally without causing pain and targeting directly on the site of interest, thereby potentially making long-term treatments more sustainable.

Pharmacological treatment with inhibitors of nuclear export enhances the antitumor activity of docetaxel in human prostate cancer

Background and aims

Docetaxel (DTX) modestly increases patient survival of metastatic castration-resistant prostate cancer (mCRPC) due to insurgence of pharmacological resistance. Deregulation of Chromosome Region Maintenance (CRM-1)/ exportin-1 (XPO-1)-mediated nuclear export may play a crucial role in this phenomenon.

Material and methods

Here, we evaluated the effects of two Selective Inhibitor of Nuclear Export (SINE) compounds, selinexor (KPT-330) and KPT-251, in association with DTX by using 22rv1, PC3 and DU145 cell lines with their. DTX resistant derivatives.

Results and conclusions

We show that DTX resistance may involve overexpression of β-III tubulin (TUBB3) and P-glycoprotein as well as increased cytoplasmic accumulation of Foxo3a. Increased levels of XPO-1 were also observed in DTX resistant cells suggesting that SINE compounds may modulate DTX effectiveness in sensitive cells as well as restore the sensitivity to DTX in resistant ones. Pretreatment with SINE compounds, indeed, sensitized to DTX through increased tumor shrinkage and apoptosis by preventing DTX-induced cell cycle arrest. Basally SINE compounds induce FOXO3a activation and nuclear accumulation increasing the expression of FOXO-responsive genes including p21, p27 and Bim causing cell cycle arrest. SINE compounds-catenin and survivin supporting apoptosis. βdown-regulated Cyclin D1, c-myc, Nuclear sequestration of p-Foxo3a was able to reduce ABCB1 and TUBB3 H2AX levels, prolonged γ expression. Selinexor treatment increased DTX-mediated double strand breaks (DSB), and reduced the levels of DNA repairing proteins including DNA PKc and Topo2A. Our results provide supportive evidence for the therapeutic use of SINE compounds in combination with DTX suggesting their clinical use in mCRPC patients.

Second-line therapy in patients with metastatic castration-resistant prostate cancer with progression after or under docetaxel: A systematic review of nine randomized controlled trials

Treatment decisions are challenging in patients with metastatic castration-resistant prostate cancer with progression after or under docetaxel. The current review systematically searched the published literature on all treatment options, and assessed the risk of bias and quality of evidence. It found the best available evidence for effective prolongation of overall survival and progression-free survival for abiraterone acetate plus prednisone versus placebo plus prednisone and enzalutamide versus placebo. Other treatment modalities could be beneficial for individual patients by taking into consideration the: selection criteria of the randomized clinical trials, risk of bias, subgroup analyses, and quality of life and adverse events. Further research is needed to determine the sequence, timing asnd combination of different treatments.