Variations in prostate biopsy recommendation and acceptance confound evaluation of risk factors for prostate cancer: Examining race and BMI

Role of N6‑methyladenosine in the pathogenesis, diagnosis and treatment of prostate cancer (Review)

Prostate cancer (PCa) affects males of all racial and ethnic groups, and leads to higher rates of mortality in those belonging to a lower socioeconomic status due to the late detection of the disease. PCa affects middle‑aged males between the ages of 45 and 60 years, and is the highest cause of cancer‑associated mortality in Western countries. As the most abundant and common mRNA modification in higher eukaryotes, N6‑methyladenosine (m6A) is widely distributed in mammalian cells and influences various aspects of mRNA metabolism. Recent studies have found that abnormal expression levels of various m6A regulators significantly affect the development and progression of various types of cancer, including PCa. The present review discusses the influence of m6A regulatory factors on the pathogenesis and progression of PCa through mRNA modification based on the current state of research on m6A methylation modification in PCa. It is considered that the treatment of PCa with micro‑molecular drugs that target the epigenetics of the m6A regulator to correct abnormal m6A modifications is a direction for future research into current diagnostic and therapeutic approaches for PCa.

Obesity and prostate cancer screening, incidence, and mortality in the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial

BACKGROUND

Though obesity, measured by body mass index (BMI), is an established risk factor for several cancer sites, there is conflicting evidence on whether obesity increases prostate cancer risk or mortality and, if it does, whether it increases risk directly or indirectly by affecting prostate cancer screening efficacy.

METHODS

We examined associations between BMI and prostate cancer screening outcomes, incidence, and mortality in men randomly assigned to the intervention arm of the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (n = 36 756) between 1993 and 2001. Participants received annual screening with the prostate-specific antigen test and digital rectal exam. Associations between baseline BMI and screening outcomes were assessed via multinomial logistic regression, and associations with prostate cancer incidence and mortality were assessed via Cox proportional hazards regression.

RESULTS

Individuals with higher BMI were less likely to screen positive via the prostate-specific antigen test and/or digital rectal exam and more likely to have an inadequate screen (all Ptrend < .01). Higher BMI was inversely associated with prostate cancer incidence (per 5 kg/m2 BMI increase: hazard ratio [HR] = 0.94, 95% confidence interval [CI] = 0.91 to 0.97), including incidence of early stage (HR = 0.94, 95% CI = 0.90 to 0.97) and advanced-stage (HR = 0.91, 95% CI = 0.82 to 1.02) disease, but positively associated with prostate cancer mortality (HR = 1.21, 95% CI = 1.06 to 1.37). The association with mortality was not modified by screening outcome (Pinteraction = .13).

CONCLUSIONS

Within this screened population, individuals with higher BMI had lower risk of prostate cancer diagnosis but higher risk of prostate cancer mortality. As higher BMI was not positively associated with advanced-stage prostate cancer risk, the increased mortality is unlikely to be due to delayed prostate cancer detection.

Serum markers, obesity and prostate cancer risk: results from the prostate cancer prevention trial

Molecular mechanisms linking obesity to prostate cancer involve steroid hormone and insulin/insulin-like growth factor 1 (IGF1) pathways. We investigated the association of circulating serum markers (e.g. androgens and IGFs/IGFBPs) with BMI and in modifying the association of obesity with prostate cancer risk. Data and specimens for this nested case-control study are from the Prostate Cancer Prevention Trial, a randomized, placebo-controlled trial of finasteride for prostate cancer prevention. Presence or absence of cancer was determined by prostate biopsy. Serum samples were assayed for sex steroid hormone concentrations and IGF1 axis analytes. Logistic regression estimated odds ratio and 95% CIs for risk of overall, low-grade (Gleason 2-6), and high-grade (Gleason 7-10) cancers. We found significant associations between BMI with serum steroids and IGFs/IGFBPs; the IGF1 axis was significantly associated with several serum steroids. Serum steroid levels did not affect the association of BMI with prostate cancer risk; however, IGFBP2 and IGFs modified the association of obesity with low- and high-grade disease. While serum steroids and IGFs/IGFBPs are associated with BMI, only the IGF1 axis contributed to obesity-related prostate cancer risk. Understanding the biological mechanisms linking obesity to prostate cancer risk as it relates to circulating serum markers will aid in developing effective prostate cancer prevention strategies and treatments.

Platelet-to-lymphocyte ratio and systemic immune-inflammation index versus circulating prostate cells to predict significant prostate cancer at first biopsy

OBJECTIVE

It has been reported that the systemic immune-inflammation index (SII) and platelet-to-lymphocyte ratio (PLR) are higher in men with prostate cancer. We compare their use with the percentage of free prostate-specific antigen (PSA), PSA density, and primary circulating prostate cells (CPCs) to predict clinically significant prostate cancer at first biopsy in men with a PSA of 4-10 ng/mL.

MATERIAL AND METHODS

Consecutive men with suspicion of prostate cancer underwent a 12-core transrectal ultrasound-guided prostate biopsy; total serum PSA, the percentage of free PSA, prostate ultrasound to calculate PSA density, and absolute neutrophil, lymphocyte, and platelet counts were used for risk assessment. CPCs were detected using differential gel centrifugation and immunocytochemistry with anti-PSA and anti-P504S. A malignant CPC was defined as a cell-expressing PSA and P504S and defined as positive or negative. Biopsies were classified as indicating cancer or no cancer. Areas under the curve for each parameter were calculated and compared, and diagnostic yields were calculated.

RESULTS

A total of 1223 men participated, and 467 (38%) had a biopsy positive for cancer, whereas 353/467 (76%) had clinically significant prostate cancer. The PLR was significantly higher in men with prostate cancer; there was no significant difference for the SII. The areas under the curves were CPC 0.84, the percentage of free PSA was 0.79, PLR 0.65, PSA density 0.62, and SII 0.46. Neither the PLR nor the SII discriminated between patients with clinically significant prostate cancer, indolent cancer, and benign prostatic disease.

CONCLUSION

Based on the results of this study, neither the SII nor PLR could differentiate between clinically significant prostate cancer and indolent cancer/benign disease at initial biopsy.