Faculty Bibliography

Despite improving outcomes, 40% of patients with newly diagnosed multiple myeloma treated with regimens containing daratumumab, a CD38-targeted monoclonal antibody, progress prematurely. By integrating tumor whole-genome and microenvironment single-cell RNA sequencing from upfront phase 2 trials using carfilzomib, lenalidomide and dexamethasone with daratumumab ( NCT03290950 ), we show how distinct genomic drivers including high APOBEC mutational activity, IKZF3 and RPL5 deletions and 8q gain affect clinical outcomes. Furthermore, evaluation of paired bone marrow profiles, taken before and after eight cycles of carfilzomib, lenalidomide and dexamethasone with daratumumab, shows that numbers of natural killer cells before treatment, high T cell receptor diversity before treatment, the disappearance of sustained immune activation (that is, B cells and T cells) and monocyte expansion over time are all predictive of sustained minimal residual disease negativity. Overall, this study provides strong evidence of a complex interplay between tumor cells and the immune microenvironment that is predictive of clinical outcome and depth of treatment response in patients with newly diagnosed multiple myeloma treated with highly effective combinations containing anti-CD38 antibodies.

PURPOSE/OBJECTIVE:Chromosome 1 (chr1) copy number abnormalities (CNAs) and structural variants (SV) are frequent in newly diagnosed multiple myeloma (NDMM) and associate with a heterogeneous impact on outcome the drivers of which are largely unknown. EXPERIMENTAL DESIGN/METHODS:A multiomic approach comprising CRISPR, gene mapping of CNA and SV, methylation, expression, and mutational analysis was used to document the extent of chr1 molecular variants and their impact on pathway utilisation. RESULTS:We identified two distinct groups of gain(1q): focal gains associated with limited gene expression changes and a neutral prognosis, and whole-arm gains, which associate with substantial gene expression changes, complex genetics and an adverse prognosis. CRISPR identified a number of dependencies on chr1 but only limited variants associated with acquired CNAs. We identified seven regions of deletion, nine of gain, three of chromothripsis (CT) and two of templated-insertion (TI), which contain a number of potential drivers. An additional mechanism involving hypomethylation of genes at 1q may contribute to the aberrant gene expression of a number of genes. Expression changes associated with whole-arm gains were substantial and gene set enrichment analysis identified metabolic processes, apoptotic resistance, signaling via the MAPK pathway, and upregulation of transcription factors as being key drivers of the adverse prognosis associated with these variants. CONCLUSIONS:Multiple layers of genetic complexity impact the phenotype associated with CNAs on chr1 to generate its associated clinical phenotype. Whole-arm gains of 1q are the critically important prognostic group that deregulate multiple pathways, which may offer therapeutic vulnerabilities.

Despite the low risk of peripherally inserted central catheter (PICC) insertion-related bleeding, the practice of administering prophylactic platelets varies greatly. Limiting unnecessary blood product transfusions reduces transfusion-related adverse events, financial cost, and delays in care. We assessed the impact of lowering prophylactic platelet administration threshold on blood product utilization patterns and bleeding events. This quasi-experimental study was conducted in an urban academic tertiary medical center. The study population included patients with platelet counts ≥ 10,000/µL and < 50,000/µL undergoing PICC placement in 2018 and 2019 when the minimum platelet thresholds were 50,000/µL and 10,000/µL, respectively. The primary outcome was blood product utilization and the secondary outcome was PICC insertion-related bleeding complications. Thirty-five patients using the 10,000/µL (10 K) platelet threshold and 46 patients using the 50,000/µL (50 K) platelet threshold were enrolled. The 50 K group received more platelets before PICC insertion (0.870 ± 0.885 and 0.143 ± 0.430 pools of platelets-per-person, p < 0.001). No patients experienced clinically significant bleeding. Immediately following PICC insertion, minor bleeding occurred in five patients (two [4.3%] and three [8.6%] in the 50 K and 10 K groups, respectively). Bleeding rates between the two cohorts did not differ (p = 0.647). Lowering the minimum platelet threshold from 50,000/µL to 10,000/µL resulted in less prophylactic platelet and total blood product administration with no appreciable difference in PICC insertion-related bleeding.

Deciphering genomic architecture is key to identifying novel disease drivers and understanding the mechanisms underlying myeloma initiation and progression. In this work, using the CoMMpass dataset, we show that structural variants (SV) occur in a nonrandom fashion throughout the genome with an increased frequency in the t(4;14), RB1, or TP53 mutated cases and reduced frequency in t(11;14) cases. By mapping sites of chromosomal rearrangements to topologically associated domains and identifying significantly upregulated genes by RNAseq we identify both predicted and novel putative driver genes. These data highlight the heterogeneity of transcriptional dysregulation occurring as a consequence of both the canonical and novel structural variants. Further, it shows that the complex rearrangements chromoplexy, chromothripsis and templated insertions are common in MM with each variant having its own distinct frequency and impact on clinical outcome. Chromothripsis is associated with a significant independent negative impact on clinical outcome in newly diagnosed cases consistent with its use alongside other clinical and genetic risk factors to identify prognosis.

The role of infection and chronic inflammation in plasma cell disorders (PCD) has been well-described. Despite not being a diagnostic criterion, infection is a common complication of most PCD and represents a significant cause of morbidity and mortality in this population. As immune-based therapeutic agents are being increasingly used in multiple myeloma, it is important to recognize their impact on the epidemiology of infections and to identify preventive measures to improve outcomes. This review outlines the multiple factors attributed to the high infectious risk in PCD (e.g. the underlying disease status, patient age and comorbidities, and myeloma-directed treatment), with the aim of highlighting future prophylactic and preventive strategies that could be implemented in the clinic. Beyond this, infection and pathogens as an entity are believed to also influence disease biology from initiation to response to treatment and progression through a complex interplay involving pathogen exposure, chronic inflammation, and immune response. This review will outline both the direct and indirect role played by oncogenic pathogens in PCD, highlight the requirement for large-scale studies to decipher the precise implication of the microbiome and direct pathogens in the natural history of myeloma and its precursor disease states, and understand how, in turn, pathogens shape plasma cell biology.

BACKGROUND:The decriminalization of marijuana and legalization of derived products requires investigation of their effect on healthcare-related outcomes. Unfortunately, little data are available on the impact of marijuana use on surgical outcomes. We aimed to determine the effect of marijuana use on 30-day complications and 1-year weight loss following laparoscopic Roux-en-Y gastric bypass (LRYGB) and laparoscopic sleeve gastrectomy (LSG). METHODS:At a large academic center, 1176 consecutive patients undergoing primary bariatric surgery from 2012 to 2017 were identified and separated into cohorts according to marijuana use. The only exclusions were 19 patients lost to follow-up. Propensity score matching, using logistic regression according to preoperative age, gender, BMI, and comorbid conditions, yielded 73 patient pairs for the control and study arms. All patients were followed two years postoperatively. RESULTS:Excess BMI lost did not differ between marijuana users and controls at 3 weeks (23.0% vs 18.9%, p = 0.095), 3 months (42.0% vs 38.1%, p = 0.416), 6 months (60.6% vs 63.1%, p = 0.631), 1 year (78.2% vs 77.3%, p = 0.789), or 2 years (89.1% vs 74.5%, p = 0.604). No differences in the rate of major 30-day postoperative complications, including readmission, infection, thromboembolic events, bleeding events and reoperation rates, were found between groups. Follow-up rate at two years was lower in marijuana users (12.3% vs 27.4%, p = 0.023). CONCLUSION:This study suggests marijuana use has no impact on 30-day complications or weight loss following bariatric surgery, and should not be a contraindication to bariatric surgery.

Pancreatic ductal adenocarcinoma (PDAC) is a lethal cancer that has proven refractory to immunotherapy. Previously, treatment with the DNA hypomethylating drug decitabine (5aza-dC; DAC) extended survival in the KPC-Brca1 mouse model of PDAC. Here we investigated the effects of DAC in the original KPC model and tested combination therapy with DAC followed by immune checkpoint inhibitors (ICI). Four protocols were tested: PBS vehicle, DAC, ICI (anti-PD-1 or anti-VISTA), and DAC followed by ICI. For each single-agent and combination treatment, tumor growth was measured by serial ultrasound, tumor infiltrating lymphoid and myeloid cells were characterized, and overall survival was assessed. Single-agent DAC led to increased CD4+ and CD8+ tumor-infiltrating T cells (TILs), PD1 expression, and tumor necrosis while slowing tumor growth and modestly increasing mouse survival without systemic toxicity. RNA-seq of DAC-treated tumors revealed increased expression of Chi3l3 (Ym1), reflecting an increase in a subset of tumor-infiltrating M2-polarized macrophages. While ICI alone had modest effects, DAC followed by either of ICI therapy additively inhibited tumor growth and prolonged mouse survival. The best results were obtained using DAC followed by anti-PD-1, which extended mean survival from 26 to 54 days (p<0.0001). In summary, low-dose DAC inhibits tumor growth and increases both TIL and a subset of tumor-infiltrating M2-polarized macrophages in the KPC model of PDAC, and DAC followed by anti-PD-1 substantially prolongs survival. Since M2-polarized macrophages are predicted to antagonize anti-tumor effects, targeting these cells may be important to enhance the efficacy of combination therapy with DAC plus ICI.