FGFR inhibition augments anti-PD-1 efficacy in murine FGFR3-mutant bladder cancer by abrogating immunosuppression.

The combination of targeted therapy with immune checkpoint inhibition (ICI) is an area of intense interest. We studied the interaction of fibroblast growth factor receptor (FGFR) inhibition with ICI in urothelial carcinoma (UC) of the bladder, in which FGFR3 is altered in 50% of cases. Using an FGFR3-driven, Trp53-mutant genetically engineered murine model (UPFL), we demonstrate that UPFL tumors recapitulate the histology and molecular subtype of their FGFR3-altered human counterparts. Additionally, UPFL1 allografts exhibit hyperprogression to ICI associated with an expansion of T regulatory cells (Tregs). Erdafitinib blocked Treg proliferation in vitro, while in vivo ICI-induced Treg expansion was fully abrogated by FGFR inhibition. Combined erdafitinib and ICI resulted in high therapeutic efficacy. In aggregate, our work establishes that, in mice, co-alteration of FGFR3 and Trp53 results in high-grade, non-muscle-invasive UC and presents a previously underappreciated role for FGFR inhibition in blocking ICI-induced Treg expansion.

Brief Report: Improving Fellow Performance of the Pharmacology Section of the American Society of Clinical Oncology In-Training Exam.

Though the electronic medical record has streamlined the process for ordering chemotherapy and reduced medical error, it has come at the cost of potentially hindering medical oncology fellows' acquisition of basic principles of chemotherapy administration. Recognizing the need for improving fellow knowledge and comfort level in chemotherapy prescription, we created an anticancer therapeutics curriculum for fellows at the University of North Carolina (UNC). The curriculum, which was comprised of a self-assessment, review session, and chemotherapy writing workshop, was offered voluntarily to all UNC fellows planning to take the medical oncology boards. We distributed a pre-intervention and post-intervention survey. In total, 11 of 18 fellows participated. After our interventions, there were statistically significant improvements in comfortability with calculating a dose of chemotherapy (p = 0.002), writing orders (p = 0.004), and taking the American Society of Clinical Oncology (ASCO) In-Training Exam (ITE) (p = 0.002). Furthermore, we saw a 4% overall improvement in pharmacology subset scores on the ITE compared to the prior year. Overall, our study suggested that the addition of a chemotherapy competency curriculum led to improved outcomes on the ASCO ITE, improved comfortability in chemotherapy administration, and hopefully improved patient care.

How to Conduct Clinical Trials of Personalized Cancer Therapies.

We identified three important principles to guide clinical trials of personalized cancer therapies: (1) incorporation of developments in molecular cancer biology in trial design; (2) inclusion of biomarkers to guide rational therapy; (3) use of innovative trial designs.

RAF1 amplification: an exemplar of MAPK pathway activation in urothelial carcinoma.

Despite recent therapeutic gains in the treatment of advanced bladder cancer, the overall survival in patients with metastatic disease remains poor and further therapeutic discovery is needed. Advanced bladder cancer is a molecularly heterogeneous disease, and the identification of driver genetic alterations has led to effective targeted therapeutic agents, such as fibroblast growth factor receptor (FGFR) inhibitors. In this issue of the JCI, Bekele et al. identify a subtype of muscle-invasive bladder cancer (MIBC) that harbors RAF1 amplification. The authors showed that RAF1 inhibition, with pan-RAF inhibitors, and the combination of RAF1 inhibition with MEK inhibition were efficacious in preclinical models harboring RAF1 amplifications as well as in tumors with HRAS and NRAS mutations. This study highlights RAF1 amplification as a driver event in bladder cancer and establishes the central role of the MAPK pathway in bladder tumorigenesis.

Targeting the Bcl-2 Family in B Cell Lymphoma.

Although lymphoma is a very heterogeneous group of biologically complex malignancies, tumor cells across all B cell lymphoma subtypes share a set of underlying traits that promote the development and sustain malignant B cells. One of these traits, the ability to evade apoptosis, is essential for lymphoma development. Alterations in the Bcl-2 family of proteins, the key regulators of apoptosis, is a hallmark of B cell lymphoma. Significant efforts have been made over the last 30 years to advance knowledge of the biology, molecular mechanisms, and therapeutic potential of targeting Bcl-2 family members. In this review, we will highlight the complexities of the Bcl-2 family, including our recent discovery of overexpression of the anti-apoptotic Bcl-2 family member Bcl-w in lymphomas, and describe recent advances in the field that include the development of inhibitors of anti-apoptotic Bcl-2 family members for the treatment of B cell lymphomas and their performance in clinical trials.

Sirtuin and pan-class I/II deacetylase (DAC) inhibition is synergistic in preclinical models and clinical studies of lymphoma.

Understanding the molecular pathogenesis of lymphoma has led to paradigm-changing treatment opportunities. One example involves tailoring specific agents based on the cell of origin in aggressive lymphomas. Germinal center (GC)-derived diffuse large B-cell lymphoma (DLBCL) is known to be driven by an addiction to Bcl6, whereas the activated B-cell (ABC) subtype is driven by nuclear factor κB. In the GC subtype, there is a critical inverse relationship between Bcl6 and p53, the functional status of which is linked to each transcription factor's degree of acetylation. Deacetylation of Bcl6 is required for its transcriptional repressor effects allowing for the oncogene to drive lymphomagenesis. Conversely, acetylation of p53 is activating when class III deacetylases (DACs), or sirtuins, are inhibited by niacinamide. Treatment of DLBCL cell lines with pan-DAC inhibitors in combination with niacinamide produces synergistic cytotoxicity in GC over ABC subtypes. This correlated with acetylation of both Bcl6 and p53. This combination also produced remissions in a spontaneous aggressive B-cell lymphoma mouse model expressing Bcl6. In a phase 1 proof-of-principle clinical trial, 24% of patients with relapsed or refractory lymphoma attained a response to vorinostat and niacinamide, and 57% experienced disease stabilization. We report herein on the preclinical and clinical activity of this targeted strategy in aggressive lymphomas. This trial was registered at www.clinicaltrials.gov as #NCT00691210.

Use of adjuvant 5-fluorouracil and radiation therapy after gastric cancer resection among the elderly and impact on survival.

PURPOSE: In randomized trials patients with resected nonmetastatic gastric cancer who received adjuvant chemotherapy and radiotherapy (chemoRT) had better survival than those who did not. We investigated the effectiveness of adjuvant chemoRT after gastric cancer resection in an elderly general population and its effects by stage. METHODS AND MATERIALS: We identified individuals in the Surveillance, Epidemiology, and End Results-Medicare database aged 65 years or older with Stage IB through Stage IV (M0) gastric cancer, from 1991 to 2002, who underwent gastric resection, using multivariate modeling to analyze predictors of chemoRT use and survival. RESULTS: Among 1,993 patients who received combined chemoRT or no adjuvant therapy after resection, having a later year of diagnosis, having a more advanced stage, being younger, being white, being married, and having fewer comorbidities were associated with combined treatment. Among 1,476 patients aged less than 85 years who survived more than 4 months, the 313 who received combined treatment had a lower mortality rate (hazard ratio, 0.83; 95% confidence interval, 0.71-0.98) than the 1,163 who received surgery alone. Adjuvant therapy significantly reduced the mortality rate for Stages III and IV (M0), trended toward improved survival for Stage II, and showed no benefit for Stage IB. We observed trends toward improved survival in all age categories except 80 to 85 years. CONCLUSIONS: The association of combined adjuvant chemoRT with improved survival in an overall analysis of Stage IB through Stage IV (M0) resected gastric cancer is consistent with clinical trial results and suggests that, in an elderly population, adjuvant chemoradiotherapy is effective. However, our observational data suggest that adjuvant treatment may not be effective for Stage IB cancer, is possibly appropriate for Stage II, and shows significant survival benefits for Stages III and IV (M0) for those aged less than 80 years.

Phase II trial evaluating the clinical and biologic effects of bevacizumab in unresectable hepatocellular carcinoma.

PURPOSE: To determine the clinical and biologic effects of bevacizumab, an anti-vascular endothelial growth factor (VEGF) monoclonal antibody, in unresectable hepatocellular carcinoma (HCC). PATIENTS AND METHODS: Adults with organ-confined HCC, Eastern Cooperative Oncology Group performance status of 0 to 2, and compensated liver disease were eligible. Patients received bevacizumab 5 mg/kg (n = 12) or 10 mg/kg (n = 34) every 2 weeks until disease progression or treatment-limiting toxicity. The primary objective was to determine whether bevacizumab improved the 6-month progression-free survival (PFS) rate from 40% to 60%. Secondary end points included determining the effects of bevacizumab on arterial enhancement and on plasma cytokine levels and the capacity of patients' plasma to support angiogenesis via an in vitro assay. RESULTS: The study included 46 patients, of whom six had objective responses (13%; 95% CI, 3% to 23%), and 65% were progression free at 6 months. Median PFS time was 6.9 months (95% CI, 6.5 to 9.1 months); overall survival rate was 53% at 1 year, 28% at 2 years, and 23% at 3 years. Grade 3 to 4 adverse events included hypertension (15%) and thrombosis (6%, including 4% with arterial thrombosis). Grade 3 or higher hemorrhage occurred in 11% of patients, including one fatal variceal bleed. Bevacizumab was associated with significant reductions in tumor enhancement by dynamic contrast-enhanced magnetic resonance imaging and reductions in circulating VEGF-A and stromal-derived factor-1 levels. Functional angiogenic activity was associated with VEGF-A levels in patient plasma. CONCLUSION: We observed significant clinical and biologic activity for bevacizumab in nonmetastatic HCC and achieved the primary study end point. Serious bleeding complications occurred in 11% of patients. Further evaluation is warranted in carefully selected patients.