Early intervention exercise training does not delay prostate cancer progression in Pten-/- mice

MiR-141-3p promotes malignant progression in prostate cancer through AlkB homolog 5-mediated m6A modification of protein arginine methyltransferase 6

Prostate cancer (PCa) is one of the leading causes of cancer-related death in males worldwide and exploring more reliable biomarkers for PCa is essential for the diagnosis and therapeutics for the disease. Although the functions of miR-141-3p and AlkB homolog 5 (ALKBH5) were identified in some cancers, whether they were involved in the development of PCa remains unclear. In this study, reverse transcription-quantitative polymerase chain reaction unveiled that the expression of ALKBH5 was reduced in PCa tissues and was negatively correlated with miR-141-3p. ALKBH5 attenuated the malignant development of PCa through suppressing the growth, migration, invasion, and sphere formation abilities of PCa cells. In addition, the luciferase activity assay identified that ALKBH5 was corroborated as a downstream target of miR-141-3p. Moreover, miR-141-3p expression was boosted in PCa tissues and cells and inhibition of miR-141-3p suppressed the tumor growth of PCa in vivo. Moreover, ALKBH5 was confirmed to suppress protein arginine methyltransferase 6 (PRMT6) expression through N6-methyladenosine (m⁶A) modification. We further identified that miR-141-3p-modulated PRMT6 level through mediating ALKBH5. Furthermore, PRMT6 level was positively correlated with miR-141-3p level and negatively associated with ALKBH5 level. Finally, rescue assays also uncovered that miR-141-3p aggravated PCa development by regulating PRMT6. In conclusion, miR-141-3p accelerated the malignant progression of PCa through ALKBH5-mediated m6A modification of PRMT6, which might offer a novel insight into the role of miR-141-3p and ALKBH5 in the treatments of PCa patients.

Effect of high-intensity interval training on aerobic capacity and fatigue among patients with prostate cancer: a meta-analysis

OBJECTIVE

This study focused on evaluating whether high-intensity interval training (HIIT) had an effect on aerobic capacity and fatigue among patients with prostate cancer (PCa) and exploring its effect on the immune system of PCa patients.

METHODS

To investigate the potential effect of HIIT on patients with prostate cancer, a meta-analysis was carried out. From January 2012 to August 2022, studies that met predefined criteria were searched in the Scopus, PubMed, Web of Science, and EBSCO databases. Analysis of the standardized mean differences was performed using Review Manager 5.4.1 software with a 95% confidence interval.

RESULTS

This review examined a total of 6 articles. There were 215 male patients with PCa involved, and the mean age was 64.4 years. According to the results of the meta-analysis, the HIIT group (n = 63) had greater VO_2peak (P<0.01) than the control group (CON) (n = 52) (P = 0.30, I² = 19% in the heterogeneity test; MD, 1.39 [0.50, 2.27]). Moreover, fatigue was significantly different (P<0.01) between the HIIT (n = 62) and CON (n = 61) groups (P = 0.78, I² = 0% in the heterogeneity test; SMD, -0.52 [-0.88, -0.16]). Furthermore, among PCa patients, HIIT showed higher efficacy (P < 0.01) in decreasing PSA than the CON regimen (P=0.22, I² = 34% in the heterogeneity test; MD, -1.13 [-1.91, -0.34]).

CONCLUSIONS

HIIT improves aerobic capacity, fatigue, and PSA levels among PCa patients but does not significantly affect IL-6 or TNF-α content. Therefore, HIIT may be a novel and potent intervention scheme for PCa patients.

Voluntary Wheel Running Does Not Enhance Radiotherapy Efficiency in a Preclinical Model of Prostate Cancer: The Importance of Physical Activity Modalities?

Physical activity is increasingly recognized as a strategy able to improve cancer patient outcome, and its potential to enhance treatment response is promising, despite being unclear. In our study we used a preclinical model of prostate cancer to investigate whether voluntary wheel running (VWR) could improve tumor perfusion and enhance radiotherapy (RT) efficiency. Nude athymic mice were injected with PC-3 cancer cells and either remained inactive or were housed with running wheels. Apparent microbubble transport was enhanced with VWR, which we hypothesized could improve the RT response. When repeating the experiments and adding RT, however, we observed that VWR did not influence RT efficiency. These findings contrasted with previous results and prompted us to evaluate if the lack of effects observed on tumor growth could be attributable to the physical activity modality used. Using PC-3 and PPC-1 xenografts, we randomized mice to either inactive controls, VWR, or treadmill running (TR). In both models, TR (but not VWR) slowed down tumor growth, suggesting that the anti-cancer effects of physical activity are dependent on its modalities. Providing a better understanding of which activity type should be recommended to cancer patients thus appears essential to improve treatment outcomes.

Regular Voluntary Running Inhibits Androgen-Independent Prostate Cancer Growth in Mice

INTRODUCTION

Benefits of regular physical exercise were demonstrated as preventive and coadjuvant nonpharmacological anticancer therapy. However, the role of exercise in modulating prostate cancer behavior has yet to be established.

METHODS

Prostate tumors were induced in C57BL/6 male mice (n = 28) by subcutaneous inoculation of a suspension of murine androgen-independent RM1 cells (1.5 × 105 cells/500 μL phosphate-buffered saline) in the dorsal region. Mice were randomly allocated into 2 study groups: sedentary tumor-induced (n = 14) and exercised tumor-induced (n = 14). Exercise consisted of voluntary running in wheeled cages. Mice (n = 7 per group) were sacrificed either 14 or 28 days after cell inoculation to evaluate tumor weight and percentage of area occupied by immunohistochemistry stained cells for Ki-67 and TdT-mediated dUTP-biotin nick end labeling, used as surrogate markers of cell proliferation and apoptosis, respectively.

RESULTS

Compared with sedentary tumor-induced mice, the tumors developed by exercised tumor-induced mice were significantly smaller at 14 days (0.17 [0.12] g vs 0.48 [0.24] g, P < .05) and at 28 days (0.92 [0.73] g vs 2.09 [1.31] g, P < .05), with smaller Ki-67 and greater TdT-mediated dUTP-biotin nick end-labeling stained areas (P < .05).

CONCLUSION

These results suggest that regular voluntary running inhibits prostate cancer cell growth by reducing cell proliferation and enhancing apoptosis.