Improved Pathologic response to chemoradiation in MGMT methylated locally advanced rectal cancer.

Background and Purpose: With the growing interest in total neoadjuvant treatment for locally advanced rectal adenocarcinoma (LARC) there is an urgent unmet need to identify predictive markers of response to long-course neoadjuvant concurrent chemoradiotherapy (LCRT). O6-Methylguanine (O6-MG)-DNA-methyltransferase (MGMT) gene methylation has been associated in some malignancies with response to concurrent chemoradiotherapy. We attempted to find if pathologic response to LCRT was associated with MGMT promoter hypermethylation (MGMTh). Materials and Methods: Patients were identified with LARC, available pre-treatment biopsy specimens, and at least 1 year of follow-up who received LCRT followed by surgical resection within 6 months. Biopsies were tested for MGMTh using a Qiagen pyrosequencing kit (Catalog number 970061). The primary outcome of LCRT responsiveness was based on tumor regression grade (TRG), with grades of 0-1 considered to have excellent response and grades of 2-3 considered to be non-responders. Secondary outcomes included overall survival (OS) and recurrence free survival (RFS). Results: Of 96 patients who met inclusion criteria, 76 had samples which produced reliable assay results. MGMTh corresponded with higher grade and age of the biopsy specimen. The percentage of responders to LCRT was higher amongst the MGMTh patients than the MGMTn patients (60.0% vs 27.5%, p value = 0.0061). MGMTh was not significantly associated with improved OS (2-year OS of 96.0% vs 98.0%, p = 0.8102) but there was a trend for improved RFS (2-year RFS of 87.6% vs 74.2%, p = 0.0903). Conclusion: Significantly greater tumor regression following LCRT was seen in MGMTh LARC. Methylation status may help identify good candidates for close observation without surgery following LCRT.

Salvage prostate bed plus elective pelvic node radiation without androgen deprivation therapy.

BACKGROUND AND PURPOSE: In men with biochemical recurrence (BCR) of prostate cancer (PCA) after radical prostatectomy (RP), there is limited data on the effectiveness of adding elective pelvic nodal radiation (EPNI) to salvage prostate bed radiation (PBRT) without androgen deprivation therapy (ADT) to prevent progression. MATERIALS AND METHODS: Retrospective chart review of 326 patients treated for BCR of PCA from a single institution was performed to capture baseline pre-operative PSA, pathologic details, post-operative PSA, treatment details (radiation and ADT), subsequent failure (rising PSA), response to radiation, and subsequent outcomes after radiation. RESULTS: Between 2004 through 2017, 326 patients received PBRT. Majority (n = 253; 78%) did not receive ADT. Majority received EPNI (n = 227; 90%) with salvage PBRT (n = 213; 94%). The median pre-PBRT PSA was 0.50 ng/ml (0.10-75.60 ng/ml). Of the patients that did not receive ADT, 83% (210/253) achieved an undetectable (< 0.2 ng/ml) PSA after salvage PBRT. After a median follow-up of 87 months, 172 (53%) patients were without a rising PSA and 50 (15%) developed metastatic disease. CONCLUSION: Outcomes with salvage PBRT plus EPNI without ADT appear comparable to salvage PBRT plus EPNI plus ADT. These results need confirmation in a randomized setting.

Holmium Laser Enucleation of Prostate in Patients with Pre-Existing Localized Prostate Cancer, Dual Center Study.

Background: Holmium laser enucleation of the prostate (HoLEP) has been used as an effective minimally invasive technique for management of enlarged prostates. We aimed to report the role of HoLEP in prostate cancer (PCa) patients either on active surveillance with bothersome lower urinary tract symptoms (LUTS) or for prostate debulking before radiation therapy and the impact on PCa management plans. Methods: Prospectively maintained database in two institutions was reviewed for patients with localized PCa managed by HoLEP with at least a follow-up of 1 year. We assessed prostate-specific antigen (PSA) trends, effect on international prostate symptom score (IPSS) and further management of PCa. Results: Out of >2000 HoLEP patients, 117 patients with a median follow-up of 30 months were included. Mean (standard deviation) age was 72.3 (±8.3) years with median (interquartile range, IQR) IPPS of 22 (16-28) and median (IQR) PSA at 7.6 (5.3-14.9) ng/mL. Gleason grade group was 1, 2, 3, and 4 in 47 (73.2%), 32 (27.35%), 7 (5.9%), and 4 (3.4%) patients, respectively. Median (IQR) PSA has significantly dropped to 1.3 (0.6-3.1), 1.4 (0.75-2.9), and 1.7 (0.86-2.75) ng/mL at 6-week, 3-month, and 1-year follow-up, respectively (p < 0.001). IPSS scores post-HoLEP obviously improved with mean (IQR) IPSS of 10 (5-13), 7 (3-12), and 3 (2-5) at 6-week, 3-month, and 1-year, respectively (p < 0.001). Eighty-eight (72%) patients stayed on active surveillance, whereas 27 (23%) patients had radiotherapy ± androgen deprivation therapy for persistently high or relapsing PSA. Within 36 intermediate-risk patients, 15 (41.6%) and patients had radiotherapy, whereas 21 (58.3%) patients continued active surveillance. Conclusions: HoLEP is beneficial in debulking large prostate in PCa patients with bothersome LUTS on active surveillance or before radiotherapy. HoLEP reduces the contribution of large adenoma to PSA level, thus reflecting PSA level better and helping reduce overtreatment.

The cost of elective nodal coverage in prostate cancer: Late quality of life outcomes and dosimetric analysis with 0, 45 or 54 Gy to the pelvis.

Purpose: Elective pelvic lymph node radiotherapy (PLNRT) in prostate cancer is often omitted from definitive (n = 267) and post prostatectomy (n = 160) radiotherapy (RT) due to concerns regarding toxicity and efficacy. Data comparing patient-reported outcome measures (PROMs) with or without PLNRT is limited. Our long-term supposition is that PLNRT, particularly to higher doses afforded by IMRT, will decrease pelvic failure rate in select patients. We aim to establish the impact of two different PLNRT doses on long term quality of life (QOL). Methods and materials: Prostate cancer patients (n = 428) recorded baseline scores using the Expanded Prostate Cancer Index Composite (EPIC), prior to definitive or post-prostatectomy RT. PLNRT, if given, was prescribed to 45 or 54 Gy at 1.8 Gy per fraction. New EPIC scores were recorded 20-36 months after radiotherapy. Absolute change in each domain subscale and summary score was recorded, along with if these changes met minimally important difference (MID) criteria. A separate multivariate analysis (MVA) was performed for each measure. Subsequent dosimetric analysis was performed. Results: Frequency of a MID decline was significantly greater with PLNRT to 54 Gy for urinary function, incontinence, and overall. No urinary decline was correlated with PLNRT to 45 Gy. PLNRT to 54 Gy was significant for decline in urinary function, bother, irritative, incontinence, and overall score in one or both MVA models while 45 Gy was not. Postoperative status was significant for decline in urinary function, incontinence, and overall. Amongst postoperative patients, there was significantly greater decline in urinary function score in the salvage setting. Neither 54 nor 45 Gy significantly affected bowel subscale or overall score decline. Conclusions: Using conventional fractionation, adding PLNRT to 54 Gy, but not 45 Gy, correlates with worse urinary QOL, with postoperative patients experiencing a steeper decline. PLNRT had no significant impact on bowel QOL with either dose.

Reference Results for Blood Parameter Changes and Recovery after Pelvic Radiation without Chemotherapy.

Introduction: There are few reports on the effect of radiation alone on blood cells (without chemotherapy). We sought to develop a single source as a reference. Materials and Methods: For over 300 prostate cancer patients treated with radiation alone, we collected the baseline, end-of-treatment and three-month post-therapy complete blood counts (CBC). Results: The hemoglobin dropped by a mean of 1.00 g/dL (−7.1%), with an RBC count of 0.40 × 1012 (−8.6%) at the end of treatment and remained significantly (but <5%) below baseline at follow-up. Significant declines were seen in the levels of the granulocytes (−12.2%; −0.67 × 109), monocytes (−2.2%; −0.05 × 109) and platelets (−12.7%; −30.31 × 109) at the end of treatment, but all returned to baseline on follow-up. The neutrophils and basophils (the primary components of the granulocytes) suffered a significant decline but returned to baseline by the follow-up. The other granulocyte components, the eosinophils, did not decline significantly. The most dramatic decline was in the levels of lymphocytes −62.5% (−1.29 × 109), which were still significantly below baseline (−38%) after two years. Conclusion: The effect of radiation is mostly transitory, with some persistence in hemoglobin/erythrocyte levels (<5%). Lymphocytes are slower to recover, remaining significantly below baseline after two years. It is noteworthy that of the patients whose lymphocytes were in the normal range at the start of therapy, only 14% were below normal at follow-up. Radiation alone has negligible-to-modest long-term effects on blood counts.

Ad Astra - telomeres in space!

PURPOSE: My journey to the stars began as I - along with the whole world - stood still and watched Neil Armstrong take those first small steps on the Moon. Fast forward 50 years and NASA astronauts Scott Kelly and Christina Koch each spend nearly a year in space aboard the International Space Station (ISS), a remarkable multinational collaborative project and floating U.S. National Laboratory that has supported continuous human presence in low Earth orbit for the past 20 years. Marking a new era of human space exploration, the first commercial rocket, SpaceX Falcon 9, recently launched NASA astronauts Doug Hurley and Bob Behnken in the Crew Dragon spacecraft Endeavor to the ISS and returned safely to Earth. NASA and its commercial partners are rapidly advancing innovative space technologies, and with the recently announced Artemis team of astronauts, plans to send the first woman and next man back to the moon and establish sustainable exploration by the end of the decade. Humankind will then be poised to take the next giant leap - pioneering human exploration of Mars. CONCLUSIONS: Historically, fewer than 600 individuals have participated in spaceflight, the vast majority of whom have been middle aged males (35-55 years) on short duration missions (less than 20 days). Thus, as the number and diversity of space travelers increase, a better understanding of how long-duration spaceflight affects human health is essential to maintaining individual astronaut performance during, and improving disease and aging trajectories following, future exploration missions. Here, I review findings from our NASA Twins Study and Telomeres investigations, highlighting potential mechanistic roles of chronic space radiation exposure in changes in telomere length and persistent DNA damage responses associated with long-duration spaceflight. Importantly, similar trends were observed in prostate cancer patients undergoing intensity-modulated radiation therapy (IMRT), additional support specifically for the role of radiation exposure. Individual differences in response were also observed in both cohorts, underscoring the importance of developing personalized approaches for evaluating human health effects and long-term outcomes associated with radiation exposures, whether on Earth or living in the extreme environment of space.

C-Reactive Protein Is a Poor Marker of Baseline Inflammation in Prostate Cancer and Response to Radiotherapy or Androgen Ablation.

Introduction C-reactive protein (CRP) is an acute-phase reactant used as a general marker for inflammation. Isolated levels have been associated with prostate cancer development, prostate-specific antigen (PSA), Gleason score, and treatment response. We seek to establish whether CRP levels reflect inflammation caused by prostate cancer by comparing levels at various points of time before, during, and after therapy. Materials and methods A total of 209 patients had a complete blood count (CBC), PSA, and CRP taken at up to four different time points. Labs were performed up to one week prior to androgen ablation via leuprolide injection (pre-AA), up to one week prior to radiotherapy (RT) (pre-RT), within one week of RT completion (post-RT), and three months following RT completion (FU [follow-up]). Results Significant relationships were found between CRP and WBC pre-AA (p-value=0.0050), pre-RT (p-value=0.0170), and post-RT (p-value=0.0113), but not at FU (p=.096). CRP had no significant relationship with PSA or lymphocytes at any time points. PSA was significantly affected by androgen ablation but lymphocytes, WBCs, and CRP were not. No CRP levels were associated with risk groups or FU-PSA. Lymphatic radiation fields significantly decreased WBCs and lymphocytes but not CRP. PSA, WBC, and lymphocytes all significantly decreased from pre-RT to post-RT, followed by a significant recovery. CRP did not significantly change during any of these periods and was not significantly related to changes in PSA, WBCs, or lymphocytes. Conclusion CRP is not a sensitive marker of the acute inflammatory effects of non-metastatic prostate cancer and treatment response with androgen ablation or radiation therapy.

Telomere Length Dynamics and Chromosomal Instability for Predicting Individual Radiosensitivity and Risk via Machine Learning.

The ability to predict a cancer patient's response to radiotherapy and risk of developing adverse late health effects would greatly improve personalized treatment regimens and individual outcomes. Telomeres represent a compelling biomarker of individual radiosensitivity and risk, as exposure can result in dysfunctional telomere pathologies that coincidentally overlap with many radiation-induced late effects, ranging from degenerative conditions like fibrosis and cardiovascular disease to proliferative pathologies like cancer. Here, telomere length was longitudinally assessed in a cohort of fifteen prostate cancer patients undergoing Intensity Modulated Radiation Therapy (IMRT) utilizing Telomere Fluorescence in situ Hybridization (Telo-FISH). To evaluate genome instability and enhance predictions for individual patient risk of secondary malignancy, chromosome aberrations were assessed utilizing directional Genomic Hybridization (dGH) for high-resolution inversion detection. We present the first implementation of individual telomere length data in a machine learning model, XGBoost, trained on pre-radiotherapy (baseline) and in vitro exposed (4 Gy γ-rays) telomere length measurements, to predict post radiotherapy telomeric outcomes, which together with chromosomal instability provide insight into individual radiosensitivity and risk for radiation-induced late effects.

Improved local control in p16 negative oropharyngeal cancers with hypermethylated MGMT.

INTRODUCTION: Patients with oropharyngeal cancers that are p16 negative (p16-) have worse outcomes than those who are p16 positive (p16+) and there is an unmet need for prognostic markers in this population. O6-Methylguanine (O6-MG)-DNA-methyltransferase (MGMT) gene methylation has been associated with response to chemoradiotherapy (CRT) in glioblastoma. We sought to find if MGMT promoter methylation was associated with outcomes of locally advanced oropharyngeal and oral cavity squamous cell carcinoma (OOSCC) in patients treated with definitive concurrent CRT. METHODS: Patients were identified with primary OOSCC, known p16 status, retrievable pre-treatment biopsies, and at least 6 months of follow-up who received definitive concurrent CRT from 2004 to 2015. Biopsies were tested for MGMT hypermethylation (MGMT+) using a Qiagen pyrosequencing kit (Catalog number 970061). Outcomes were subsequently recorded and analyzed. RESULTS: Fifty-eight patients were included with a median follow up of 78 (range 6-196) months. Fourteen patients (24.1%) had oral cavity cancer and 44 (75.9%) had oropharyngeal cancer. A significant difference was found for local recurrence free survival (LRFS) by combined MGMT and p16 status (p = 0.0004). Frequency of LR in MGMT+/p16+, MGMT+/p16-, MGMT-/p16+, and MGMT-p16- patients was 14.3%, 14.3%, 13.0%, and 69.2%, respectively (p = 0.0019). A significant difference was not found for distant recurrence free survival (p = 0.6165) or overall survival (p = 0.1615). LRFS remained significant on analysis restricted to oropharyngeal cancer patients (p-value = 0.0038). CONCLUSION: Patients who are p16- and MGMT+ with oropharyngeal and oral cavity squamous cell carcinoma have significantly better LC with definitive CRT than those who are p16- and MGMT-. Prospective studies are needed to verify these findings.

The effect of pelvic radiation alone on lymphocyte subgroups.

There is a lack of information on the radiosensitivity of lymphocyte subgroups to radiation alone. CD4+ and CD8+ lymphocytes respond similarly. CD 19+ dropped most precipitously, but recovered to levels similar to the other subgroups by 3 months. NK cells decline more modestly and recover more fully by 3 months.

The effect of radiation therapy on post-prostatectomy urinary function.

AIM: We sought to evaluate the effect of radiation therapy on post-prostatectomy urinary quality of life in prostate cancer patients. BACKGROUND: In some men with non-metastatic prostate cancer, radiation therapy is indicated following prostatectomy. The radiation toxicity and quality of life considerations are unique in the post-prostatectomy setting. MATERIALS AND METHODS: A total of 106 patients receiving post-prostatectomy radiation therapy completed the Expanded Prostate Cancer Index Composite questionnaire before radiation and at 2-year follow-up. The primary outcomes of this study were the urinary domain summary score and subscale scores. Planned analysis was performed based on time interval from prostatectomy to radiation therapy. RESULTS: Among the 106 patients analyzed, the mean urinary domain summary score worsened at 2-year follow-up after radiation therapy, lowering from 77.23-72.51 (p = 0.0085). Similar worsening was observed in the subscales of function (p = 0.003), bother (p = 0.0397), and incontinence (p = 0.0003). Urinary incontinence showed the greatest observable change among subscales. While the summary score worsened (p = 0.0031) among patients receiving radiation therapy more than 1 year after prostatectomy, it did not show statistically significant change in those treated 1 year or less after prostatectomy. CONCLUSION: Our results demonstrate that post-prostatectomy radiation therapy is associated with modest declines in reportable urinary quality of life. Patients receiving radiation therapy more than 1 year after prostatectomy showed greater worsening of urinary quality of life, which indicates that there may be no functional advantage to delaying radiation therapy beyond the initial postoperative period.

Risk factors for locoregional relapse after radical nephrectomy.

AIM: To identify risk factors for locoregional relapse after radical nephrectomy for renal cell carcinoma. METHODS: We retrospectively reviewed the charts of 259 patients who underwent radical nephrectomy for sporadic clinically localized unilateral renal cell carcinoma between 1998 and 2012. Relapse patterns (locoregional and/or distant) were identified. Relapse-free survival was calculated using Kaplan-Meier method. Factors associated with decreased relapse-free survival were identified using univariate and multivariate Cox proportional hazards regression model analysis. Locoregional relapse estimates were calculated for individual factors and combination of factors. RESULTS: At a median follow-up of 68 months (interquartile range: 75 months), 24% patients relapsed. Of these, 54% had locoregional relapse. High-grade, positive margin, large tumor size and stage III/IV were associated with worse relapse-free survival on multivariate analysis. Locoregional relapse occurred among patients with tumor size >7-10 cm (35%), stage III/IV (31%), grade III/IV (26%), renal vein invasion (22%), perinephric fat invasion (30%), 7 cm plus grade I/II (21%), >7 cm plus grade III/IV (48%), stage III/IV plus grade I/II (24%) and stage III/IV plus grade III/IV (45%). CONCLUSION: We were able to discern risk factors (individual or in combination) associated with increased risk of locoregional relapse after radical nephrectomy for renal cell carcinoma. This could help distinguish patients who may benefit from adjuvant locoregionally directed therapy.

Intensity modulated radiation therapy after extra-pleural pneumonectomy for malignant pleural mesothelioma is feasible without fatal pulmonary toxicity and provides good survival.

AIM: To analyze patterns of failure, toxicity, relapse-free survival (RFS), and overall survival (OS) in malignant pleural mesothelioma (MPM) patients treated with intensity-modulated radiation therapy following extrapleural pneumonectomy (EPP). METHODS: We reviewed 18 charts of patients with MPM from 2005 to 2014 who underwent EPP followed by hemithoracic intensity-modulated radiation therapy. Intensity-modulated radiation therapy dose delivery adhered to published lung dose constraints. Kaplan-Meier curves were used to assess the RFS and OS. Median survival times are reported for both RFS and OS. RESULTS: Median age was 65 years (range: 40-76 years). Chemotherapy was administered in four neo-adjuvant and seven adjuvant patients. Pathological American Joint Committee on Cancer stages II, III, IV, surgical margin, lympho-vascular space, pericardium, and chest wall involvement were seen in 3, 12, 3, 9, 7, 12 and 3 patients, respectively. The majority of the patients received 45 Gy in 25 fractions. The mean lung dose was 7.14 Gy (range: 5 Gy-9.3 Gy). The mean V20 was 2.23%. At a median follow-up of 3 years, eight patients were alive (44%); 10 experienced relapse (56%). Median RFS and OS were 24.4 months (95% CI: >16.3 months) and 38.2 months (95% CI: 17.4-78.1 months), respectively. Acute toxicities were fatigue, dermatitis, nausea, esophagitis/dysphagia, cough, and dyspnea on exertion. No grade III, IV, or fatal pulmonary toxicities were observed. CONCLUSION: Intensity-modulated radiation therapy following EPP for MPM resulted in RFS and OS comparable to the published literature without significant toxicity.

To B(iopsy) or not to B(iopsy).

Often in metastatic disease, biopsy confirmation of suspicious central nervous system (CNS) lesions is not mandated according to the American College of Radiology, International Radiosurgery Association, and the National Comprehensive Cancer Network. We present a case of an individual who was thought to have metastatic nonsmall cell lung cancer (NSCLC) T2aN0M1b with motor deficits and CNS metastasis to the left postcentral gyrus. The patient underwent biopsy of the primary lung mass confirming NSCLC. He subsequently underwent treatment with stereotactic radiosurgery (SRS) for presumed CNS oligometastatic disease and palliative chemotherapy. Two months after SRS, the patient had progression of CNS disease with new motor deficits. A magnetic resonance imaging revealed and enlarging mass in the previously radiated area. The patient underwent craniotomy with tumor resection and a second primary CNS tumor was discovered. That patient was downstaged from a Stage IV to a Stage IIB lung cancer with concomitant CNS primary.

Single fraction spine stereotactic ablative body radiotherapy with volumetric modulated arc therapy.

This study investigated a single institution's experience with volumetric modulated arc therapy (VMAT) directed stereotactic ablative body radiotherapy (SABR) for vertebral metastases. From 2010 to 2014, 95 lesions of spinal metastases in 73 patients were treated with SABR using VMAT. Clinical local control, pain level, and use of steroid medication were employed to evaluate treatment responses. The majority (79%) of patients were treated with a radiation dose of 20 Gy in a single fraction. However, when normal tissue constraints could not be achieved, the dose was reduced to 18 Gy (11%) or 16 Gy (8%) in 1 fraction. At the median follow up of 12.7 months (mean 18.0, range 1-56 months), clinical local control was 97% (92 out of 95). There was a mean 81% (median 100%, range 28-100%) decrease in subjective pain score. Seventy-seven percent of patients had a decrease in narcotic pain medication use. Pain was completely resolved at the treatment site for 69% (66/95) of patients. Prior to the SABR treatment, 33% (31/95) of patients had epidural extension of tumor. Among patients with epidural involvement, 45% (14/31) exhibited neurologic impairment prior to treatment. Twenty-three percent (7/31) experienced spinal cord compression. Prior to treatment, 34 patients experienced some form of neurologic impairment. Of these patients, 24% (8/34) experienced improved motor functioning; the remaining 76% (26/34) of patients' neurological dysfunction were stable. Our results indicate the SABR regimen using VMAT technique is clinically effective in achieving clinical local control and palliation. This is the first publication reporting clinical outcomes of VMAT directed SABR.

Durability of Artificial Urinary Sphincter With Prior Radiation Therapy.

BACKGROUND: The aim of this study was to investigate the effect of prior radiation therapy on artificial urinary sphincter. METHODS: Group 1 was comprised of 63 men who underwent prior radical prostatectomy, and Group 2 was comprised of 31 men who received prior radiation therapy with or without prior radical prostatectomy. Social incontinence was defined as requiring to use > 1 pad per day and/or catheter-dependent at the time of last follow-up. RESULTS: The median age at artificial urinary sphincter placement was 71 years (interquartile range, 55-74 years). The median and mean follow-up was 62 months (interquartile range, 37-106 months) and 75 months (range, 2-205 months), respectively. At the time of last follow-up, 67% (63 of 94) of the men in the entire cohort (73% [46 of 63] and 55% [17 of 31] in Group 1 and Group 2, respectively [P = .078]) were socially continent. Sphincter revision, erosion, infection, and removal rates were 20%, 20%, 7%, and 10%, respectively, in Group 1, and 26%, 13%, 7%, and 23%, respectively, in Group 2. The differences in these rates were not statistically significant between the 2 groups. CONCLUSION: We found no significant difference in functionality (incontinence rates) and outcomes (rates of sphincter revision, erosion, infection, and removal) between the 2 groups. The message for patients is that prior radiation does not significantly alter the outcomes of artificial urinary sphincter.

Congenital B cell lymphocytosis explained by novel germline CARD11 mutations.

Nuclear factor-κB (NF-κB) controls genes involved in normal lymphocyte functions, but constitutive NF-κB activation is often associated with B cell malignancy. Using high-throughput whole transcriptome sequencing, we investigated a unique family with hereditary polyclonal B cell lymphocytosis. We found a novel germline heterozygous missense mutation (E127G) in affected patients in the gene encoding CARD11, a scaffolding protein required for antigen receptor (AgR)-induced NF-κB activation in both B and T lymphocytes. We subsequently identified a second germline mutation (G116S) in an unrelated, phenotypically similar patient, confirming mutations in CARD11 drive disease. Like somatic, gain-of-function CARD11 mutations described in B cell lymphoma, these germline CARD11 mutants spontaneously aggregate and drive constitutive NF-κB activation. However, these CARD11 mutants rendered patient T cells less responsive to AgR-induced activation. By reexamining this rare genetic disorder first reported four decades ago, our findings provide new insight into why activating CARD11 mutations may induce B cell expansion and preferentially predispose to B cell malignancy without dramatically perturbing T cell homeostasis.

Burkitt lymphoma pathogenesis and therapeutic targets from structural and functional genomics.

Burkitt's lymphoma (BL) can often be cured by intensive chemotherapy, but the toxicity of such therapy precludes its use in the elderly and in patients with endemic BL in developing countries, necessitating new strategies. The normal germinal centre B cell is the presumed cell of origin for both BL and diffuse large B-cell lymphoma (DLBCL), yet gene expression analysis suggests that these malignancies may use different oncogenic pathways. BL is subdivided into a sporadic subtype that is diagnosed in developed countries, the Epstein-Barr-virus-associated endemic subtype, and an HIV-associated subtype, but it is unclear whether these subtypes use similar or divergent oncogenic mechanisms. Here we used high-throughput RNA sequencing and RNA interference screening to discover essential regulatory pathways in BL that cooperate with MYC, the defining oncogene of this cancer. In 70% of sporadic BL cases, mutations affecting the transcription factor TCF3 (E2A) or its negative regulator ID3 fostered TCF3 dependency. TCF3 activated the pro-survival phosphatidylinositol-3-OH kinase pathway in BL, in part by augmenting tonic B-cell receptor signalling. In 38% of sporadic BL cases, oncogenic CCND3 mutations produced highly stable cyclin D3 isoforms that drive cell cycle progression. These findings suggest opportunities to improve therapy for patients with BL.

Oncogenically active MYD88 mutations in human lymphoma.

The activated B-cell-like (ABC) subtype of diffuse large B-cell lymphoma (DLBCL) remains the least curable form of this malignancy despite recent advances in therapy. Constitutive nuclear factor (NF)-κB and JAK kinase signalling promotes malignant cell survival in these lymphomas, but the genetic basis for this signalling is incompletely understood. Here we describe the dependence of ABC DLBCLs on MYD88, an adaptor protein that mediates toll and interleukin (IL)-1 receptor signalling, and the discovery of highly recurrent oncogenic mutations affecting MYD88 in ABC DLBCL tumours. RNA interference screening revealed that MYD88 and the associated kinases IRAK1 and IRAK4 are essential for ABC DLBCL survival. High-throughput RNA resequencing uncovered MYD88 mutations in ABC DLBCL lines. Notably, 29% of ABC DLBCL tumours harboured the same amino acid substitution, L265P, in the MYD88 Toll/IL-1 receptor (TIR) domain at an evolutionarily invariant residue in its hydrophobic core. This mutation was rare or absent in other DLBCL subtypes and Burkitt's lymphoma, but was observed in 9% of mucosa-associated lymphoid tissue lymphomas. At a lower frequency, additional mutations were observed in the MYD88 TIR domain, occurring in both the ABC and germinal centre B-cell-like (GCB) DLBCL subtypes. Survival of ABC DLBCL cells bearing the L265P mutation was sustained by the mutant but not the wild-type MYD88 isoform, demonstrating that L265P is a gain-of-function driver mutation. The L265P mutant promoted cell survival by spontaneously assembling a protein complex containing IRAK1 and IRAK4, leading to IRAK4 kinase activity, IRAK1 phosphorylation, NF-κB signalling, JAK kinase activation of STAT3, and secretion of IL-6, IL-10 and interferon-ß. Hence, the MYD88 signalling pathway is integral to the pathogenesis of ABC DLBCL, supporting the development of inhibitors of IRAK4 kinase and other components of this pathway for the treatment of tumours bearing oncogenic MYD88 mutations.

The rs10993994 risk allele for prostate cancer results in clinically relevant changes in microseminoprotein-beta expression in tissue and urine.

BACKGROUND: Microseminoprotein-beta (MSMB) regulates apoptosis and using genome-wide association studies the rs10993994 single nucleotide polymorphism in the MSMB promoter has been linked to an increased risk of developing prostate cancer. The promoter location of the risk allele, and its ability to reduce promoter activity, suggested that the rs10993994 risk allele could result in lowered MSMB in benign tissue leading to increased prostate cancer risk. METHODOLOGY/PRINCIPAL FINDINGS: MSMB expression in benign and malignant prostate tissue was examined using immunohistochemistry and compared with the rs10993994 genotype. Urinary MSMB concentrations were determined by ELISA and correlated with urinary PSA, the presence or absence of cancer, rs10993994 genotype and age of onset. MSMB levels in prostate tissue and urine were greatly reduced with tumourigenesis. Urinary MSMB was better than urinary PSA at differentiating men with prostate cancer at all Gleason grades. The high risk allele was associated with heterogeneity of MSMB staining and loss of MSMB in both tissue and urine in benign prostate. CONCLUSIONS: These data show that some high risk alleles discovered using genome-wide association studies produce phenotypic effects with potential clinical utility. We provide the first link between a low penetrance polymorphism for prostate cancer and a potential test in human tissue and bodily fluids. There is potential to develop tissue and urinary MSMB for a biomarker of prostate cancer risk, diagnosis and disease monitoring.