Best of 2022 in prostate cancer and prostatic diseases

Effect of yoga as a complementary therapy in prostate cancer survivors: a systematic review

PURPOSE

Currently, available evidence suggests a positive impact of yoga on physical and psychological well-being in patients across different types of cancer, especially breast cancer survivors. However, there are no available systematic reviews on the effects of yoga on male prostate cancer survivors. The objective of the current systematic review is to specifically examine the quality of life, feasibility, and other effects of yoga on prostate cancer survivors.

METHODS

Bibliographic databases such as PubMed/Medline, CINAHL, EMBASE, Cochrane Library, and Google Scholar were searched for studies that were conducted till December 2022 to assess the effect of yoga on prostate cancer survivors. Studies that met predefined eligibility criteria were included. The quality of the included studies was assessed by the Cochrane risk of bias tool, and for single-arm studies, the Newcastle-Ottawa Scale was used.

RESULTS

A comprehensive literature search yielded a total of 137 studies. After careful consideration, this review included five studies involving 129 prostate cancer survivors. The included studies were published between 2012 and 2022. This systematic review observed that yoga has the potential to enhance erectile function, reduce fatigue and urinary symptoms, alleviate psychological stress, boost immune function, and improve the overall quality of life in prostate cancer survivors. Furthermore, it demonstrates the feasibility of incorporating yoga into their regular routine.

CONCLUSIONS

Yoga could be an effective complementary therapy in the management of physical and psychological symptoms experienced by prostate cancer survivors. However, until more comprehensive evidence becomes available, it would be premature to draw definitive conclusions about the effectiveness of yoga in the context of prostate cancer (PCa).

A hospital-based study of prostate biopsy results in Indian males

Introduction

The prostate is a gland belonging to the male reproductive system. Aging results in the dysfunction of the prostate that may present as inflammation, enlargement, and cancer. Additionally, the diseases of the prostate including cancers are slow in progression, and therefore, it is difficult to diagnose them early. Hence, it is increasingly important for physicians to recommend histopathological examination of the prostate gland to identify, manage, and treat prostate cancers. This study was conducted to assess prostate diseases among biopsy specimen collected from patients with signs of prostate diseases.

Materials and Methods

This prospective study was conducted in the Department of Pathology, Deccan College of Medical Sciences, Owaisi Hospital, Hyderabad, between June 2012 and September 2014. All gross specimens (n = 300) of the prostate such as the needle biopsies of the prostate, transurethral resection of the prostate (TURP) chips, and excised specimens of the prostate were included in the study. Histopathological examinations of the biopsies were performed for nuclear size, chromatin material, nucleoli, membrane thickness, irregularity, cytoplasmic granularity, staining, and cell border conspicuity. The biopsies were also assessed for lobule formation, secretions, polymorphonuclear leukocytes, lymphocytes, macrophages, connective tissue stromal cells, their arrangements, and acellular connective tissue material.

Results

Of 300 total prostatic biopsies performed, 56 (18.66%) were identified as inflammatory lesions of the prostate (prostatitis), 98 (32.66%) revealed benign prostatic lesions (benign prostatic hyperplasia (BPH)), 112 (37.33%) were identified as BPH with premalignant lesions, and 34 (11.33%) were revealed as malignant tumors of the prostate. Chronic prostatitis (67.85%) was the common inflammatory lesion. The majority (91.42%) revealed epithelial lesions compared to stromal lesions (08.58%). BPH was predominantly (28.00%) noticed among patients in the age group of 61-70 years. Prostatic intraepithelial neoplasia (PIN) was observed majorly (53.35%) in the age group of 61-70 years. Most of the prostatic cancers were identified as adenocarcinomas. However, three variants were also categorized as small cell carcinoma, signet ring cell carcinoma, and transitional cell carcinomas.

Conclusions

The results reveal that prostatic adenocarcinomas are predominant among the study population. Additionally, prostatic diseases including cancer are commonly noticed among people belonging to the age group of 61-70 years. More than one-third of patients showed BPH with premalignant lesions, and a majority of the study population showed evidence of chronic prostatitis.

GLIS1, Correlated with Immune Infiltrates, Is a Potential Prognostic Biomarker in Prostate Cancer

Prostate cancer (PCa) is a prevalent malignant disease and the primary reason for cancer-related mortality among men globally. GLIS1 (GLIS family zinc finger 1) is a key regulator in various pathologies. However, the expression pattern, clinical relevance, and immunomodulatory function of GLIS1 in PCa remain unclear. In this study, GLIS1 was discovered to serve as a key gene in PCa by integrating mRNA and miRNA expression profiles from GEO database. We systematically explored the expression and prognostic values of GLIS1 in cancers using multiple databases. Additionally, we examined the functions of GLIS1 and the relationship between GLIS1 expression levels and immune infiltration in PCa. Results showed that GLIS1 was differentially expressed between normal and tumor tissues in various cancer types and was significantly low-expressed in PCa. Low GLIS1 expression was associated with poor PCa prognosis. GLIS1 was also involved in the activation, proliferation, differentiation, and migration of immune cells, and its expression showed a positive correlation with the infiltration of various immune cells. Moreover, GLIS1 expression was positively associated with various chemokines/chemokine receptors, indicating the involvement in regulating immune cell migration. In summary, GLIS1 is a potential prognostic biomarker and a therapeutic target to modulate anti-tumor immune response in PCa.

Mechanism of tumor-derived extracellular vesicles in prostatic cancer progression through the circFMN2/KLF2/RNF128 axis

Circular RNAs (circRNAs) are a major type of cargos encapsulated in extracellular vesicles (EVs) and regulate the progression of prostatic cancer (PC). This study was conducted to explore the role of tumor-derived EVs in PC cell proliferation, invasion, and migration via shuttle of circRNA formin 2 (circFMN2). RT-qPCR or Western blot assay showed that circFMN2 was upregulated while KLF2 and RNF128 were downregulated in PC tissues and cells. EVs were separated from PC cells and characterized and its internalization in PC cells was examined, which suggested that PC-EVs mediated the shuttle of circFMN2 to upregulate circFMN2 expression in PC cells. PC cell functions were determined by cell counting kit-8, colony formation and Transwell assays, which suggested that PC-EVs fueled the proliferation, invasion, and migration of PC cells. At cellular level, PC-EVs mediated the shuttle of circFMN2 to upregulate circFMN2 expression in PC cells, and circFMN2 binding to HuR decreased the HuR-KLF2 interaction and repressed KLF2 expression, which further reduced the KLF2-RNF128 promoter binding and repressed RNF128 transcription. Overexpression of KLF2/RNF128 ablated the effects of PC-EVs on the proliferation, invasion, and migration of PC cells. The xenograft tumor models and lung/liver metastasis models were established and revealed that PC-EVs accelerated tumorigenesis and metastasis in vivo via delivery of circFMN2 and repression of KLF2/RNF128.

Castration promotes the browning of the prostate tumor microenvironment

BACKGROUND

Adipose tissue has gained attention due to its potential paracrine role. Periprostatic adipose tissue surrounds the prostate and the prostatic urethra, and it is an essential player in prostate cancer progression. Since obesity is directly related to human tumor progression, and adipose tissue depots are one of the significant components of the tumor microenvironment, the molecular mediators of the communication between adipocytes and epithelial cells are in the spotlight. Although periprostatic white adipose tissue contributes to prostate cancer progression, brown adipose tissue (BAT), which has beneficial effects in metabolic pathologies, has been scarcely investigated concerning cancer progression. Given that adipose tissue is a target of androgen signaling, the actual role of androgen removal on the periprostatic adipose tissue was the aim of this work.

METHODS

Surgical castration of the transgenic adenocarcinoma of the mouse prostate (TRAMP) was employed. By histology examination and software analysis, WAT and BAT tissue was quantified. 3T3-like adipocytes were used to study the role of Casodex® in modifying adipocyte differentiation and to investigate the function of the secretome of adipocytes on the proliferation of androgen-dependent and independent prostate cancer cells. Finally, the role of cell communication was assayed by TRAMP-C1 xenograft implanted in the presence of 3T3-like adipocytes.

RESULTS

Androgen removal increases brown/beige adipose tissue in the fat immediately surrounding the prostate glands of TRAMP mice, concomitant with an adjustment of the metabolism. Castration increases body temperature, respiratory exchange rate, and energy expenditure. Also, in vitro, it is described that blocking androgen signaling by Casodex® increases the uncoupling protein 1 (UCP1) marker in 3T3-like adipocytes. Finally, the effect of brown/beige adipocyte secretome was studied on the proliferation of prostate cancer cells in vivo and in vitro. The secretome of brown/beige adipocytes reduces the proliferation of prostate cancer cells mediated partly by the secretion of extracellular vesicles.

CONCLUSIONS

Consequently, we concluded that hampering androgen signaling plays a crucial role in the browning of the periprostatic adipose tissue. Also, the presence of brown adipocytes exhibits the opposite effect to that of white adipocytes in vitro regulating processes that govern the mechanisms of cell proliferation of prostate cancer cells. And finally, promoting the browning of adipose tissue in the periprostatic adipose tissue might be a way to handle prostate cancer cell progression. Video Abstract.