Addressing racial disparities in prostate cancer pathology prediction models: external validation and comparison of four models of pathological outcome prediction before radical prostatectomy in the multiethnic SEARCH cohort.

BACKGROUND: Certain widely used pathological outcome prediction models that were developed in tertiary centers tend to overpredict outcomes in the community setting; thus, the Michigan Urological-Surgery Improvement Collaborative (MUSIC) model was developed in general urology practice to address this issue. Additionally, the development of these models involved a relatively small proportion of Black men, potentially compromising the accuracy of predictions in this patient group. We tested the validity of the MUSIC and three widely used nomograms to compare their overall and race-stratified predictive performance. METHODS: We extracted data from 4139 (1138 Black) men from the Shared Equal Access Regional Cancer Hospital (SEARCH) database of the Veterans Affairs health system. The predictive performance of the MUSIC model was compared to the Memorial-Sloan Kettering (MSK), Briganti-2012, and Partin-2017 models for predicting lymph-node invasion (LNI), extra-prostatic extension (EPE), and seminal vesicle invasion (SVI). RESULTS: The median PSA of Black men was higher than White men (7.8 vs. 6.8 ng/ml), although they were younger by a median of three years and presented at a lower-stage disease. MUSIC model showed comparable discriminatory capacity (AUC:77.0%) compared to MSK (79.2%), Partin-2017 (74.6%), and Briganti-2012 (76.3%), with better calibration for LNI. AUCs for EPE and SVI were 72.7% and 76.9%, respectively, all comparable to the MSK and Partin models. LNI AUCs for Black and White men were 69.6% and 79.6%, respectively, while EPE and SVI AUCs were comparable between races. EPE and LNI had worse calibration in Black men. Decision curve analysis showed MUSIC superiority over the MSK model in predicting LNI, especially among Black men. CONCLUSION: Although the discriminatory performance of all models was comparable for each outcome, the MUSIC model exhibited superior net benefit to the MSK model in predicting LNI outcomes among Black men in the SEARCH population.

Contemporary risk of biochemical recurrence after radical prostatectomy in the active surveillance era.

OBJECTIVES: To assess whether contemporary risks of biochemical recurrence (BCR) after radical prostatectomy (RP) in the AS era differ from historical estimates due to changes in tumor risk case mix and improvements in risk stratification. MATERIALS AND METHODS: We sampled 6,682 men who underwent RP for clinically localized disease between 2000 and 2017 from the VA SEARCH database. Kaplan Meier analysis was used to calculate incidence of BCR before and after 2010 overall and within tumor risk subgroups. Multivariable Cox proportional hazard regression analysis including an interaction term between era and tumor risk was used to compare risk of BCR before and after 2010 overall and across tumor risk subgroups. RESULTS: About 3,492 (52%) and 3,190 (48%) men underwent RP before and after 2010, respectively. In a limited multivariable model excluding tumor risk, overall BCR risk was higher post-2010 vs. pre-2010 (HR: 1.15, 95%CI: 1.05-1.25; 40% vs 36% at 8 years post-RP). However, this effect was eliminated after correcting for tumor risk (HR: 0.95, 95%CI: 0.87-1.04), suggesting that differences in tumor risk between eras mediated the change. Yet, within tumor-risk subgroups, BCR risk was significantly lower for favorable intermediate-risk (HR: 0.76, 95%CI:0.60-0.96) and unfavorable intermediate-risk PC (HR: 0.78, 95%CI: 0.67-0.90), but significantly higher for high-risk PC (HR: 1.22, 95%CI: 1.07-1.38) in the post-2010 era. 8-year risks of BCR in the post-2010 era were 21% (95%CI: 16%-25%), 25% (95%CI: 20%-30%), 41% (95%CI: 37%-46%), and 60% (95%CI: 56%-64%) for low-, FIR-, UIR-, and high-risk disease, respectively. Limitations include limited long-term follow-up in the post-2010 subgroup. CONCLUSIONS: Overall BCR risk has increased in the AS era, driven by a higher risk case mix and increased BCR risk among high-risk patients. Physicians should quote contemporary estimates of BCR when counseling patients.

Do Hispanic Puerto Rican men have worse outcomes after radical prostatectomy? Results from SEARCH.

BACKGROUND: We previously reported that outcomes after radical prostatectomy (RP) were similar among non-Hispanic Black, non-Hispanic White, and Hispanic White Veterans Affairs (VA) patients. However, prostate cancer (PC) mortality in Puerto Rican Hispanics (PRH) may be higher than in other Hispanic groups. Data focused on PRH patients is sparse; thus, we tested the association between PR ethnicity and outcomes after RP. METHODS: Analysis included men in SEARCH cohort who underwent RP (1988-2020, n = 8311). PRH patients (n = 642) were treated at the PR VA, and outcomes were compared to patients treated in the Continental US regardless of race. Logistic regression was used to test the associations between PRH and PC aggressiveness, adjusting for demographic and clinicopathological features. Multivariable Cox models were used to investigate PRH versus Continental differences in biochemical recurrence (BCR), metastases, castration-resistant PC (CRPC), and PC-specific mortality (PCSM). RESULTS: Compared to Continental patients, PRH patients had lower adjusted odds of pathological grade group ≥2 (p < 0.001), lymph node metastasis (p < 0.001), and positive margins (p < 0.001). In contrast, PRH patients had higher odds of extracapsular extension (p < 0.001). In Cox models, PRH patients had a higher risk for BCR (HR = 1.27, p < 0.001), metastases (HR = 1.49, p = 0.014), CRPC (HR = 1.80, p = 0.001), and PCSM (HR = 1.74, p = 0.011). Further adjustment for extracapsular extension and other pathological variables strengthened these findings. CONCLUSIONS: In an equal access setting, PRH RP patients generally had better pathological features, but despite this, they had significantly worse post-treatment outcomes than men from the Continental US, regardless of race. The reasons for the poorer prognosis among PRH men require further research.

Postradical prostatectomy prostate-specific antigen outcomes after 6 versus 18 months of perioperative androgen-deprivation therapy in men with localized, unfavorable intermediate-risk or high-risk prostate cancer: Results of part 2 of a randomized phase 2 trial.

BACKGROUND: Patients with localized, unfavorable intermediate-risk and high-risk prostate cancer have an increased risk of relapse after radical prostatectomy (RP). The authors previously reported on part 1 of this phase 2 trial testing neoadjuvant apalutamide, abiraterone, prednisone, plus leuprolide (AAPL) or abiraterone, prednisone, and leuprolide (APL) for 6 months followed by RP. The results demonstrated favorable pathologic responses (tumor <5 mm) in 20.3% of patients (n = 24 of 118). Herein, the authors report the results of part 2. METHODS: For part 2, patients were randomized 1:1 to receive either AAPL for 12 months (arm 2A) or observation (arm 2B), stratified by neoadjuvant therapy and pathologic tumor classification. The primary end point was 3-year biochemical progression-free survival. Secondary end points included safety and testosterone recovery (>200 ng/dL). RESULTS: Overall, 82 of 118 patients (69%) enrolled in part 1 were randomized to part 2. A higher proportion of patients who were not randomized to adjuvant therapy had a favorable prostatectomy pathologic response (32.3% in nonrandomized patients compared with 17.1% in randomized patients). In the intent-to-treat analysis, the 3-year biochemical progression-free survival rate was 81% for arm 2A and 72% for arm 2B (hazard ratio, 0.81; 90% confidence interval, 0.43-1.49). Of the randomized patients, 81% had testosterone recovery in the AAPL group compared with 95% in the observation group, with a median time to recovery of <12 months in both arms. CONCLUSIONS: In this study, because 30% of patients declined adjuvant treatment, part B was underpowered to detect differences between arms. Future perioperative studies should be biomarker-directed and include strategies for investigator and patient engagement to ensure compliance with protocol procedures.

Are associations between obesity and prostate cancer outcomes following radical prostatectomy the same in smokers and non-smokers? Results from the SEARCH Cohort.

PURPOSE: Obesity and smoking have been associated with poor prostate cancer (PC) outcomes. We investigated associations between obesity and biochemical recurrence (BCR), metastasis, castrate resistant-PC (CRPC), PC-specific mortality (PCSM), and all-cause mortality (ACM) and examined if smoking modified these associations. METHODS: We analyzed SEARCH Cohort data from men undergoing RP between 1990 and 2020. Cox regression models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between body mass index (BMI) as a continuous variable and weight status classifications (normal: 18.5 ≤ 25 kg/m2; overweight: 25-29.9 kg/m2; obese: ≥ 30 kg/m2) and PC outcomes. RESULTS: Among 6,241 men, 1,326 (21%) were normal weight, 2,756 (44%) overweight and 2159 (35%) obese; 1,841 (30%) were never-smokers, 2,768 (44%) former and 1,632 (26%) current-smokers. Among all men, obesity was associated with non-significant increased risk of PCSM, adj-HR = 1.71; 0.98-2.98, P = 0.057, while overweight and obesity were inversely associated with ACM, adj-HR = 0.75; 0.66-0.84, P < 0.001 and adj-HR = 0.86; 0.75-0.99, P = 0.033, respectively. Other associations were null. BCR and ACM were stratified for smoking status given evidence for interactions (P = 0.048 and P = 0.054, respectively). Among current-smokers, overweight was associated with an increase in BCR (adj-HR = 1.30; 1.07-1.60, P = 0.011) and a decrease in ACM (adj-HR = 0.70; 0.58-0.84, P < 0.001). Among never-smokers, BMI (continuous) was associated with an increase in ACM (adj-HR = 1.03; 1.00-1.06, P = 0.033). CONCLUSIONS: While our results are consistent with obesity as a risk factor for PCSM, we present evidence of effect modification by smoking for BCR and ACM highlighting the importance of stratifying by smoking status to better understand associations with body weight.

Diabetes and Prostate Cancer Outcomes in Men with Nonmetastatic Castration-Resistant Prostate Cancer: Results from the SEARCH Cohort.

BACKGROUND: The prognosis of diabetic men with advanced prostate cancer is poorly understood and understudied. Hence, we studied associations between diabetes and progression to metastases, prostate cancer-specific mortality (PCSM) and all-cause mortality (ACM) in men with nonmetastatic castration-resistant prostate cancer (nmCRPC). METHODS: Data from men diagnosed with nmCRPC between 2000 and 2017 at 8 Veterans Affairs Health Care Centers were analyzed using Cox regression to determine HRs and 95% confidence intervals (CI) for associations between diabetes and outcomes. Men with diabetes were classified according to: (i) ICD-9/10 codes only, (ii) two HbA1c values > 6.4% (missing ICD-9/10 codes), and (iii) all diabetic men [(i) and (ii) combined]. RESULTS: Of 976 men (median age: 76 years), 304 (31%) had diabetes at nmCRPC diagnosis, of whom 51% had ICD-9/10 codes. During a median follow-up of 6.5 years, 613 men were diagnosed with metastases, and 482 PCSM and 741 ACM events occurred. In multivariable-adjusted models, ICD-9/10 code-identified diabetes was inversely associated with PCSM (HR, 0.67; 95% CI, 0.48-0.92) while diabetes identified by high HbA1c values (no ICD-9/10 codes) was associated with an increase in ACM (HR, 1.41; 95% CI, 1.16-1.72). Duration of diabetes, prior to CRPC diagnosis was inversely associated with PCSM among men identified by ICD-9/10 codes and/or HbA1c values (HR, 0.93; 95% CI, 0.88-0.98). CONCLUSIONS: In men with late-stage prostate cancer, ICD-9/10 'code-identified' diabetes is associated with better overall survival than 'undiagnosed' diabetes identified by high HbA1c values only. IMPACT: Our data suggest that better diabetes detection and management may improve survival in late-stage prostate cancer.

A modeling study to estimate prostate cancer-specific mortality on active surveillance for men with favorable intermediate-risk prostate cancer: Results from the SEARCH cohort.

PURPOSE: Limited data exist to help surgeons decide between active surveillance (AS) versus treatment for men with favorable intermediate risk (FIR) prostate cancer. To estimate the theoretical excess risk of prostate cancer-specific mortality (PCSM) with AS versus radical prostatectomy (RP), we determined the risk of PCSM in FIR men undergoing RP and modeled the PCSM risk for AS using a range of increased PSCM scenarios ranging from 1.25x to 2x higher relative to RP. MATERIALS AND METHODS: We retrospectively reviewed data from men undergoing RP from 1988 to 2017 at 8 Veterans Affairs hospitals within the SEARCH cohort. Men with FIR PC were identified using the NCCN risk criteria. Risk of PCSM at 5, 10, and 15 years after RP was estimated. Using these estimates, PCSM was then modeled for AS using a range of increased risk of PCSM relative to RP ranging from 1.25x to 2x higher. RESULTS: For the 920 FIR men identified, 5-, 10-, and 15-year survival estimates for PCSM after RP were 99.9%, 99.0%, and 97.8%, respectively. If the risk of PCSM on AS were 1.25-2x greater than RP, there would be 0.54%-2.17% excess risk of PCSM at 15 years. CONCLUSIONS: The risk of death for FIR after RP is very low. Assuming even modestly increased PCSM with AS versus RP, the excess risk of death for AS in FIR is low even up to 15 years. These data support the consideration of AS as a relatively safe alternative to RP in FIR men, though prospective randomized trials are needed to validate these findings.

Prognostic Value of the Intermediate-risk Feature in Men with Favorable Intermediate-risk Prostate Cancer: Implications for Active Surveillance.

Background: Guidelines suggest that active surveillance (AS) may be considered for select patients with favorable intermediate-risk (fIR) prostate cancer. Objective: To compare the outcomes between fIR prostate cancer patients included by Gleason score (GS) or prostate-specific antigen (PSA). Most patients are classified with fIR disease due to either a 3 + 4 = 7 GS (fIR-GS) or a PSA level of 10-20 ng/ml (fIR-PSA). Previous research suggests that inclusion by GS 7 may be associated with worse outcomes. Design setting and participants: We conducted a retrospective cohort study of US veterans diagnosed with fIR prostate cancer from 2001 to 2015. Outcome measurements and statistical analysis: We compared the incidence of metastatic disease, prostate cancer-specific mortality (PCSM), all-cause mortality (ACM), and receipt of definitive treatment between fIR-PSA and fIR-GS patients managed with AS. Outcomes were compared with those of a previously published cohort of patients with unfavorable intermediate-risk disease using cumulative incidence function and Gray's test for statistical significance. Results and limitations: The cohort included 663 men; 404 had fIR-GS (61%) and 249 fIR-PSA (39%). There was no evidence of difference in the incidence of metastatic disease (8.6% vs 5.8%, p = 0.77), receipt of definitive treatment (77.6% vs 81.5%, p = 0.43), PCSM (5.7% vs 2.5%, p = 0.274), and ACM (16.8% vs 19.1%, p = 0.14) between the fIR-PSA and fIR-GS groups at 10 yr. On multivariate regression, unfavorable intermediate-risk disease was associated with higher rates of metastatic disease, PCSM, and ACM. Limitations included varying surveillance protocols. Conclusions: There is no evidence of difference in oncological and survival outcomes between men with fIR-PSA and fIR-GS prostate cancer undergoing AS. Thus, presence of GS 7 disease alone should not exclude patients from consideration of AS. Shared decision-making should be utilized to optimize management for each patient. Patient summary: In this report, we compared the outcomes of men with favorable intermediate-risk prostate cancer in the Veterans Health Administration. We found no significant difference between survival and oncological outcomes.

Time from biopsy to radical prostatectomy by race in an equal-access healthcare system: Results from the SEARCH cohort.

BACKGROUND: We previously showed that within an equal-access health system, race was not associated with the time between prostate cancer (PC) diagnosis and radical prostatectomy (RP). However, in the more recent time-period of the study (2003-2007), Black men had significantly longer times to RP. We sought to revisit the question in a larger study population with more contemporary patients. We hypothesized that time from diagnosis to treatment would not differ by race, even after accounting for active surveillance (AS) and the exclusion of men at very low to low risk of PC progression. METHODS: We analyzed data from 5885 men undergoing RP from 1988 to 2017 at eight Veterans Affairs Hospitals from SEARCH. Multiple linear regression was used to compare time from biopsy to RP and to examine the risk of delays (>90 and >180 days) between races. In sensitivity analyses we excluded men deemed to have initially chosen AS based on having >365 days from biopsy to RP and men at very low to low PC risk for progression according to National Comprehensive Cancer Network Clinical Practice Guidelines. RESULTS: At biopsy, Black men (n = 1959) were younger, had lower body mass index, and higher prostate specific antigen levels, (all p < 0.02), compared to White men (n = 3926). Time from biopsy to RP was longer in Black men (mean days: 98 vs. 92; adjusted ratio of mean number of days, 1.07 [95% confidence interval: 1.03-1.11], p < 0.001); however, there were no differences in delays >90 or >180 days after adjusting for confounders (all p ≥ 0.286). Results were similar following the exclusion of men potentially under on AS and at very low and low risk. CONCLUSIONS: In an equal-access healthcare system, we did not find evidence of clinically relevant differences in time from biopsy to RP in Black versus White men.

Automated Patient-level Prostate Cancer Detection with Quantitative Diffusion Magnetic Resonance Imaging.

Background: Multiparametric magnetic resonance imaging (mpMRI) improves detection of clinically significant prostate cancer (csPCa), but the subjective Prostate Imaging Reporting and Data System (PI-RADS) system and quantitative apparent diffusion coefficient (ADC) are inconsistent. Restriction spectrum imaging (RSI) is an advanced diffusion-weighted MRI technique that yields a quantitative imaging biomarker for csPCa called the RSI restriction score (RSIrs). Objective: To evaluate RSIrs for automated patient-level detection of csPCa. Design setting and participants: We retrospectively studied all patients (n = 151) who underwent 3 T mpMRI and RSI (a 2-min sequence on a clinical scanner) for suspected prostate cancer at University of California San Diego during 2017-2019 and had prostate biopsy within 180 d of MRI. Intervention: We calculated the maximum RSIrs and minimum ADC within the prostate, and obtained PI-RADS v2.1 from medical records. Outcome measurements and statistical analysis: We compared the performance of RSIrs, ADC, and PI-RADS for the detection of csPCa (grade group ≥2) on the best available histopathology (biopsy or prostatectomy) using the area under the curve (AUC) with two-tailed α = 0.05. We also explored whether the combination of PI-RADS and RSIrs might be superior to PI-RADS alone and performed subset analyses within the peripheral and transition zones. Results and limitations: AUC values for ADC, RSIrs, and PI-RADS were 0.48 (95% confidence interval: 0.39, 0.58), 0.78 (0.70, 0.85), and 0.77 (0.70, 0.84), respectively. RSIrs and PI-RADS were each superior to ADC for patient-level detection of csPCa (p < 0.0001). RSIrs alone was comparable with PI-RADS (p = 0.8). The combination of PI-RADS and RSIrs had an AUC of 0.85 (0.78, 0.91) and was superior to either PI-RADS or RSIrs alone (p < 0.05). Similar patterns were seen in the peripheral and transition zones. Conclusions: RSIrs is a promising quantitative marker for patient-level csPCa detection, warranting a prospective study. Patient summary: We evaluated a rapid, advanced prostate magnetic resonance imaging technique called restriction spectrum imaging to see whether it could give an automated score that predicted the presence of clinically significant prostate cancer. The automated score worked about as well as expert radiologists' interpretation. The combination of the radiologists' scores and automated score might be better than either alone.

Tele-Untethered: Telemedicine Without Waiting Rooms.

BACKGROUND AND OBJECTIVES: Telemedicine bridges the gap between care needs and provider availability. The value of telemedicine can be eclipsed by long wait times, especially if patients are stuck in virtual waiting rooms. UCSD Tele-Untethered allows patients to join visits without waiting in virtual waiting rooms. Tele-Untethered uses a text-to-video link to improve clinic flow, decrease virtual waiting room reliance, improve throughput, and potentially improve satisfaction. METHODS: This institutional review board (IRB)-approved quality improvement pilot (IRB #210364QI) included patients seen in a single vascular neurology clinic, within the pilot period, if they had a smartphone/cell phone, and agreed to participate in a flexible approach to telehealth visits. Standard work was disseminated (patient instructions, scripting, and workflows). Patients provided a cell phone number to receive a text link when the provider was ready to see them. Metrics included demographics, volumes, visit rates, percentage seen early/late, time savings, and satisfaction surveys. RESULTS: Over 2.5 months, 22 patients were scheduled. Of those arriving, 76% were "Tele-Untethered" and 24% were "Standard Telemedicine." Text-for-video link was used for 94% of Tele-Untethered. Fifty-five percent were seen early. There was a 55-minute-per-session time savings. CONCLUSION: This UCSD Tele-Untethered pilot benefitted patients by allowing scheduling flexibility while not being tied to a "virtual waiting room." It benefited providers as it allowed them to see patients in order/not tied to exact times, improved throughput, and saved time. Even modest time savings for busy providers, coupled with Lean workflows, can provide critical value. High Tele-Untethered uptake and use of verbal check-in highlight that patients expect flexibility and ease of use. As our initial UCSD Tele-Untethered successes included patient flexibility and time savings for patients and providers, it can serve as a model as enterprises strive for optimal care and improved satisfaction. Expansion to other clinic settings is underway with a mantra of "UCSD Tele-Untethered: Your provider can see you now."

Validation of the prostate cancer comorbidity index in predicting cause-specific mortality in men undergoing radical prostatectomy.

PURPOSE: Accurate prediction of competing risks of mortality remains a key component of prostate cancer treatment decision-making. We sought to validate the Prostate Cancer Comorbidity Index (PCCI) score for predicting other-cause mortality (OCM) and cancer outcomes in men undergoing radical prostatectomy (RP). MATERIALS AND METHODS: We sampled 4857 men with prostate cancer treated with RP in the VA from 2000-2018. Risks of OCM, 90-day all-cause mortality (ACM), prostate cancer-specific mortality, metastasis, and biochemical recurrence by PCCI score were assessed using Cox proportional hazards and logistic regression. We compared prediction of 90-day ACM between PCCI and the American Society of Anesthesiology (ASA) score, a validated predictor of short-term mortality. RESULTS: Over median follow-up of 6.7 years (IQR 3.7-10.3), there was a stepwise increase in risk of OCM with higher PCCI score, with hazards (95%CI) of 1.53 (1.14-2.04), 2.11 (1.55-2.88), 2.36 (1.68-3.31), 3.61 (2.61-4.98), and 4.99 (3.58-6.96) for PCCI 1-2, 3-4, 5-6, 7-9, and 10 + (vs. 0), respectively. Projected 10-year cumulative incidence of OCM was 8%, 12%, 16%, 19%, 26%, and 32% for scores of 0, 1-2, 3-4, 5-6, 7-9, and 10+ , respectively. Men with PCCI 7+ had greater odds of 90-day ACM (OR 3.48, 95%CI 1.26-9.63) while men with higher ASA did not. Higher PCCI score was associated with worse cancer outcomes, with the highest categories driving the associations. CONCLUSIONS: The PCCI is a robust measure of short- and long-term OCM after RP, validated for use in clinical care and health services research focusing on surgical patient populations.

Is time to castration resistant prostate cancer a potential intermediate end-point for time to metastasis among men initiating androgen deprivation therapy for non-metastatic prostate cancer with rapid PSA doubling time (<9 months)?

PURPOSE: Metastasis-free survival (MFS) is a surrogate for overall survival (OS) in men with non-metastatic castration-resistant prostate cancer (CRPC), but this endpoint may take years to develop in men with non-metastatic castrate-sensitive disease. The study objective was to examine whether progression to CRPC is a potential intermediate endpoint for developing metastatic disease in patients with biochemical recurrence (BCR) after radical prostatectomy (RP). MATERIALS AND METHODS: Men with BCR following RP who had PSA doubling times (PSADT) < 9 months and no metastasis at the time of initiating androgen deprivation therapy (ADT) (n = 210) were included. The primary objective was to assess the correlation between CRPC-free survival (CRPC-FS) and MFS, and the secondary objective was to assess the correlation between time to metastasis and time to CRPC. Kendall's Tau was used to test the correlation for the primary and secondary outcomes. RESULTS: The median MFS was 104 months (95% CI: 83-114) and median CRPC-FS was 100 months (95% CI: 80-114). Based on the Kaplan-Meier curve, the greatest difference in time to MFS and CRPC-FS was around 70% free survival, which was reached at 61.2 months for MFS and 49.6 months for CRPC-FS. Kendall's Tau for the correlation between CRPC-FS and MFS and between time to CRPC and time to metastasis was 0.867 (95% CI: 0.765-0.968) and 0.764 (95% CI: 0.644-0.884), respectively. CONCLUSIONS: Given the high correlation between CRPC-FS and MFS, after validation, CRPC-FS may serve as a potential intermediate endpoint in trials for men with BCR initiating ADT following local therapy.

Integrins Increase Sarcoplasmic Reticulum Activity for Excitation-Contraction Coupling in Human Stem Cell-Derived Cardiomyocytes.

Engagement of the sarcoplasmic reticulum (SR) Ca2+ stores for excitation-contraction (EC)-coupling is a fundamental feature of cardiac muscle cells. Extracellular matrix (ECM) proteins that form the extracellular scaffolding supporting cardiac contractile activity are thought to play an integral role in the modulation of EC-coupling. At baseline, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) show poor utilisation of SR Ca2+ stores, leading to inefficient EC-coupling, like developing or human CMs in cardiac diseases such as heart failure. We hypothesised that integrin ligand-receptor interactions between ECM proteins and CMs recruit the SR to Ca2+ cycling during EC-coupling. hiPSC-CM monolayers were cultured on fibronectin-coated glass before 24 h treatment with fibril-forming peptides containing the integrin-binding tripeptide sequence arginine-glycine-aspartic acid (2 mM). Micropipette application of 40 mM caffeine in standard or Na+/Ca2+-free Tyrode's solutions was used to assess the Ca2+ removal mechanisms. Microelectrode recordings were conducted to analyse action potentials in current-clamp. Confocal images of labelled hiPSC-CMs were analysed to investigate hiPSC-CM morphology and ultrastructural arrangements in Ca2+ release units. This study demonstrates that peptides containing the integrin-binding sequence arginine-glycine-aspartic acid (1) abbreviate hiPSC-CM Ca2+ transient and action potential duration, (2) increase co-localisation between L-type Ca2+ channels and ryanodine receptors involved in EC-coupling, and (3) increase the rate of SR-mediated Ca2+ cycling. We conclude that integrin-binding peptides induce recruitment of the SR for Ca2+ cycling in EC-coupling through functional and structural improvements and demonstrate the importance of the ECM in modulating cardiomyocyte function in physiology.

Analogy Powered by Prediction and Structural Invariants: Computationally Led Discovery of a Mesoporous Hydrogen-Bonded Organic Cage Crystal.

Mesoporous molecular crystals have potential applications in separation and catalysis, but they are rare and hard to design because many weak interactions compete during crystallization, and most molecules have an energetic preference for close packing. Here, we combine crystal structure prediction (CSP) with structural invariants to continuously qualify the similarity between predicted crystal structures for related molecules. This allows isomorphous substitution strategies, which can be unreliable for molecular crystals, to be augmented by a priori prediction, thus leveraging the power of both approaches. We used this combined approach to discover a rare example of a low-density (0.54 g cm-3) mesoporous hydrogen-bonded framework (HOF), 3D-CageHOF-1. This structure comprises an organic cage (Cage-3-NH2) that was predicted to form kinetically trapped, low-density polymorphs via CSP. Pointwise distance distribution structural invariants revealed five predicted forms of Cage-3-NH2 that are analogous to experimentally realized porous crystals of a chemically different but geometrically similar molecule, T2. More broadly, this approach overcomes the difficulties in comparing predicted molecular crystals with varying lattice parameters, thus allowing for the systematic comparison of energy-structure landscapes for chemically dissimilar molecules.

Clinically Localized Prostate Cancer: AUA/ASTRO Guideline. Part III: Principles of Radiation and Future Directions.

PURPOSE: The summary presented herein represents Part III of the three-part series dedicated to Clinically Localized Prostate Cancer: AUA/ASTRO Guideline, discussing principles of radiation and offering several future directions of further relevant study in patients diagnosed with clinically localized prostate cancer. Please refer to Parts I and II for discussion of risk assessment, staging, and risk-based management (Part I), and principles of active surveillance and surgery and follow-up (Part II). MATERIALS AND METHODS: The systematic review utilized to inform this guideline was conducted by an independent methodological consultant. A research librarian conducted searches in Ovid MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. The methodology team supplemented searches of electronic databases with the studies included in the prior AUA review and by reviewing reference lists of relevant articles. RESULTS: The Clinically Localized Prostate Cancer Panel created evidence- and consensus-based guideline statements to aid clinicians in the management of patients with clinically localized prostate cancer. Statements regarding management of patients using radiation therapy as well as important future directions of research are detailed herein. CONCLUSIONS: This guideline aims to inform clinicians treating patients with clinically localized prostate cancer. Continued research and publication of high-quality evidence from future trials will be essential to further improve care for these men.

Clinically Localized Prostate Cancer: AUA/ASTRO Guideline, Part I: Introduction, Risk Assessment, Staging, and Risk-Based Management.

PURPOSE: The summary presented herein represents Part I of the three-part series dedicated to Clinically Localized Prostate Cancer: AUA/ASTRO Guideline, discussing risk assessment, staging, and risk-based management in patients diagnosed with clinically localized prostate cancer. Please refer to Parts II and III for discussion of principles of active surveillance, surgery and follow-up (Part II), and principles of radiation and future directions (Part III). MATERIALS AND METHODS: The systematic review utilized to inform this guideline was conducted by an independent methodological consultant. A research librarian conducted searches in Ovid MEDLINE, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews. The methodology team supplemented searches of electronic databases with the studies included in the prior AUA review and by reviewing reference lists of relevant articles. RESULTS: The Clinically Localized Prostate Cancer Panel created evidence- and consensus-based guideline statements to aid clinicians in the management of patients with clinically localized prostate cancer. Statements regarding risk assessment, staging, and risk-based management are detailed herein. CONCLUSIONS: This guideline aims to inform clinicians treating patients with clinically localized prostate cancer. Continued research and publication of high-quality evidence from future trials will be essential to further improve care for these men.