Atezolizumab combined with immunogenic salvage chemoimmunotherapy in patients with transformed diffuse large B-cell lymphoma.

Patients with relapsed/refractory (R/R) transformed diffuse large B-cell lymphoma (DLBCL) from indolent B-cell lymphomas, including Richter transformation (RT), have a poor prognosis. PD-1/PD-L1 antibodies produce modest objective and complete response rates (ORR and CRR) in B-NHL as monotherapy but may synergize with immunogenic chemotherapies like gemcitabine and oxaliplatin (GemOx). Thus, we evaluated the safety and efficacy of atezolizumab plus rituximab and GemOx (R-GemOx+Atezo) in R/R transformed DLBCL, including RT. We conducted a phase I trial including patients with transformed DLBCL after ≥1 prior therapy. Patients received up to 4 cycles of R-GemOx-+Atezo. Patients in CR could then proceed to Ratezo maintenance until progression. A safety lead-in with dose-limiting toxicity (DLT) evaluation was enrolled to confirm the recommended phase 2 dose (RP2D), followed by 2 expansion cohorts: one for transformed follicular lymphoma (FL) and another for non-FL transformed DLBCL, including RT. Twenty-seven patients were enrolled. One of the 6 safety lead-in patients had a DLT attributed to atezolizumab, a grade 4 Stevens-Johnson syndrome (SJS). The most common grade ≥3 events were neutropenia (18.5%), lymphopenia (18.5%), and thrombocytopenia (14.8%). The overall and complete response rates (ORR and CRR) were 59% and 33%, respectively. The ORR and CRR in transformed FL were 79% and 43%, and 38% and 23% in transformed non-FL, respectively. The median PFS and OS of the total population were 4.2 and 7.7 months, respectively. R-GemOx+Atezo was well tolerated and demonstrated promising preliminary efficacy in patients with R/R transformed DLBCL.

Phase II study of the histone deacetylase inhibitor vorinostat (Suberoylanilide Hydroxamic Acid; SAHA) in recurrent or metastatic transitional cell carcinoma of the urothelium - an NCI-CTEP sponsored: California Cancer Consortium trial, NCI 6879.

BACKGROUND: Until the advent of T cell check point inhibitors standard second-line therapy for patients with metastatic urothelial cancer (mUC) was undefined. Histone deacetylase inhibitors (HDACi) have anti-cancer activity in a variety of tumor models including modulation of apoptosis in bladder cancer cell lines. We evaluated the efficacy and toxicity of the HDACi vorinostat in patients with mUC failing first-line platinum-based therapy either in the adjuvant/neoadjuvant setting or for recurrent/advanced disease. METHODS: Vorinostat was given orally 200 mg twice daily continuously until progression or unacceptable toxicity. The primary end point was RECIST response rate (RR); a RR > 20% was deemed interesting in a 2-stage design requiring one response in the first 12 patients to proceed to 2nd stage for a total of 37 subjects. CT or MRI scan imaging occurred every 6 weeks. RESULTS: Fourteen patients were accrued characterized by: median age 66 years (43-84); Caucasian (79%); males (86%); and Karnofsky performance status ≥90 (50%). Accrual was terminated in the first stage as no responses were observed. Best response was stable disease (3 patients). Progression was observed in 8 patients. Two patients came off therapy prior to re-imaging and a 3rd patient died while on treatment and was not assessed for response. Median number of cycles was 2 (range 1-11). Median disease-free survival and overall survival times were 1.1 (0.8, 2.1) & 3.2 (2.1, 14.5) months, respectively. Toxicities were predominantly cytopenias and thrombocytopenic bleeding. Two pts. had grade 5 toxicity unlikely related to treatment. Two pts. had grade 4 and 6 had grade 3 toxicities observed. Two patients with stable disease remained on therapy for 6+ cycles. CONCLUSIONS: Vorinostat on this dose-schedule had limited efficacy and significant toxicity resulting in a unfavorable risk:benefit ratio in patients with mUC. NCT00363883.

Fluorescence techniques used to measure interactions between hydroxyapatite nanoparticles and epidermal growth factor receptors.

The potential applications of nanomaterials in therapeutics are immense and to fully explore this potential, it is important to understand the interaction of nanoparticles with cellular components. To examine the interaction between nanoparticles and cell membrane receptors, this report describes the use of advanced fluorescence techniques to measure interactions between hydroxyapatite (HA) nanoparticles and epidermal growth factor receptors (EGFRs), as a model system. FITC-labelled HA nanoparticles and monomeric red fluorescent protein (mRFP)-conjugated EGFRs expressed in Chinese hamster ovary cells (CHO-K1) were generated and their interaction measured using acceptor photobleaching-fluorescence resonance energy transfer (AP-FRET) and fluorescence lifetime imaging microscopy-fluorescence resonance energy transfer (FLIM-FRET). Results confirmed that hydroxyapatite nanoparticles not only interacted with EGFR but also attenuated downstream EGFR signalling, possibly by hindering normal dimerization of EGFR. Furthermore, the extent of signal attenuation suggested correlation with specific surface area of the nanoparticles, whereby greater specific surface area resulted in greater downstream signal attenuation. This novel demonstration establishes fluorescence techniques as a viable method to study nanoparticle interactions with proteins such as cell surface receptors. The approach described herein can be extended to study interactions between any fluorescently labelled nanoparticle-biomolecule pair.

The role of the tumor suppressor p53 pathway in the cellular DNA damage response to zinc oxide nanoparticles.

In this paper, we explored how ZnO nanoparticles cross-interact with a critical tumor suppressive pathway centered around p53, which is one of the most important known tumor suppressors that protects cells from developing cancer phenotypes through its control over major pathways like apoptosis, senescence and cell cycle progression. We showed that the p53 pathway was activated in BJ cells (skin fibroblasts) upon ZnO nanoparticles treatment with a concomitant decrease in cell numbers. This suggests that cellular responses like apoptosis in the presence of ZnO nanoparticles require p53 as the molecular master switch towards programmed cell death. This also suggests that in cells without robust p53, protective response can be tipped towards carcinogenesis when stimulated by DNA damage inducing agents like ZnO nanoparticles. We observed this precarious tendency in the same BJ cells with p53 knocked down using endogeneous expressing shRNA. These p53 knocked down BJ cells became more resistant to ZnO nanoparticles induced cell death and increased cell progression. Collectively, our results suggest that cellular response towards specific nanoparticle induced cell toxicity and carcinogenesis is not only dependent on specific nanoparticle properties but also (perhaps more importantly) the endogenous genetic, transcriptomic and proteomic landscape of the target cells.