Effect of preoperative programmed death-1 or programmed death ligand-1 immune check point inhibition on complications after surgery for primary head and neck cancer.

BACKGROUND: There is sparse literature on the effect of preoperative immunotherapy on complications after surgery for primary head and neck squamous cell carcinoma (HNSCC). The objectives are to compare complication rates in patients receiving surgery with and without neoadjuvant immune checkpoint inhibitors (nICI) for primary HNSCC and to evaluate factors associated with increased odds of surgical complications. METHODS: A retrospective review of patients who underwent ablation and free flap reconstruction or transoral robotic surgery (TORS) for primary HNSCC between 2017-2021 was conducted. Complications were compared between patients who underwent surgery with or without nICI before and after propensity score matching. Regression analysis to estimate odds ratios was performed. RESULTS: A total of 463 patients met inclusion criteria. Free flap reconstruction constituted 28.9% of patients and TORS constituted 71.1% of patients. nICI was administered in 83 of 463 (17.9%) patients. There was no statistically significant difference in surgical, medical, or overall complications between patients receiving surgery with or without nICI. In the unmatched cohort, multivariable model identified non-White race, former/current smoking history, free flap surgery, and perineural invasion as factors significantly associated with increased complications. In the matched cohort, multivariable model identified advanced age and free flap surgery as factors significantly associated with increased complications. PLAIN LANGUAGE SUMMARY: It is safe to give immunotherapy before major surgery in patients who have head and neck cancer. Advanced age, non-White race, current/former smoking, free flap surgery, and perineural invasion may be associated with increased the odds of surgical complications.

IL-8 correlates with nonresponse to neoadjuvant nivolumab in HPV positive HNSCC via a potential extracellular vesicle miR-146a mediated mechanism.

Therapy using anti-PD-1 immune checkpoint inhibitors (ICI) has revolutionized the treatment of many cancers including head and neck squamous cell carcinomas (HNSCC), but only a fraction of patients respond. To better understand the molecular mechanisms driving resistance, we performed extensive analysis of plasma and tumor tissues before and after a 4-week neoadjuvant trial in which HNSCC patients were treated with the anti-PD-1 inhibitor, nivolumab. Luminex cytokine analysis of patient plasma demonstrated that HPVpos nonresponders displayed high levels of the proinflammatory chemokine, interleukin-8 (IL-8), which decreased after ICI treatment, but remained higher than responders. miRNAseq analysis of tetraspanin-enriched small extracellular vesicles (sEV) purified from plasma of HPVpos nonresponders demonstrated significantly lower levels of seven miRNAs that target IL-8 including miR-146a. Levels of the pro-survival oncoprotein Dsg2, which has been to down-regulate miR-146a, are elevated with HPVpos tumors displaying higher levels than HPVneg tumors. Dsg2 levels decrease significantly following ICI in responders but not in nonresponders. In cultured HPVpos cells, restoration of miR-146a by forced expression or treatment with miR-146a-loaded sEV, reduced IL-8 level, blocked cell cycle progression, and promoted cell death. These findings identify Dsg2, miR-146a, and IL-8 as potential biomarkers for ICI response and suggest that the Dsg2/miR-146a/IL-8 signaling axis negatively impacts ICI treatment outcomes and could be targeted to improve ICI responsiveness in HPVpos HNSCC patients.

Expanding the Pipeline to Teach: Recruiting Future Urban Teachers of Color Through a Dual Enrollment Program.

This qualitative case study explores the perceptions of schools, schooling, and teaching prior to and after engagement in a dual enrollment program. Data from nine participants revealed insights into the ways pre-college students thought about careers in teaching, how experiences in the dual enrollment program shaped their interest in teaching, and their perceptions of the pathways to and aspirations for teaching. Pre-college students envisioned teaching as a career possibility due to intrinsic factors, such as intellectual interests and racial identity; these factors were reinforced by family and salient schooling experiences. The dual enrollment program confirmed prior interests in teaching through its focus on the education major, mentoring, and the opportunity to take college coursework at the host university.

Durvalumab plus tremelimumab alone or in combination with low-dose or hypofractionated radiotherapy in metastatic non-small-cell lung cancer refractory to previous PD(L)-1 therapy: an open-label, multicentre, randomised, phase 2 trial.

BACKGROUND: Patients with non-small-cell lung cancer (NSCLC) that is resistant to PD-1 and PD-L1 (PD[L]-1)-targeted therapy have poor outcomes. Studies suggest that radiotherapy could enhance antitumour immunity. Therefore, we investigated the potential benefit of PD-L1 (durvalumab) and CTLA-4 (tremelimumab) inhibition alone or combined with radiotherapy. METHODS: This open-label, multicentre, randomised, phase 2 trial was done by the National Cancer Institute Experimental Therapeutics Clinical Trials Network at 18 US sites. Patients aged 18 years or older with metastatic NSCLC, an Eastern Cooperative Oncology Group performance status of 0 or 1, and progression during previous PD(L)-1 therapy were eligible. They were randomly assigned (1:1:1) in a web-based system by the study statistician using a permuted block scheme (block sizes of three or six) without stratification to receive either durvalumab (1500 mg intravenously every 4 weeks for a maximum of 13 cycles) plus tremelimumab (75 mg intravenously every 4 weeks for a maximum of four cycles) alone or with low-dose (0·5 Gy delivered twice per day, repeated for 2 days during each of the first four cycles of therapy) or hypofractionated radiotherapy (24 Gy total delivered over three 8-Gy fractions during the first cycle only), 1 week after initial durvalumab-tremelimumab administration. Study treatment was continued until 1 year or until progression. The primary endpoint was overall response rate (best locally assessed confirmed response of a partial or complete response) and, along with safety, was analysed in patients who received at least one dose of study therapy. The trial is registered with ClinicalTrials.gov, NCT02888743, and is now complete. FINDINGS: Between Aug 24, 2017, and March 29, 2019, 90 patients were enrolled and randomly assigned, of whom 78 (26 per group) were treated. This trial was stopped due to futility assessed in an interim analysis. At a median follow-up of 12·4 months (IQR 7·8-15·1), there were no differences in overall response rates between the durvalumab-tremelimumab alone group (three [11·5%, 90% CI 1·2-21·8] of 26 patients) and the low-dose radiotherapy group (two [7·7%, 0·0-16·3] of 26 patients; p=0·64) or the hypofractionated radiotherapy group (three [11·5%, 1·2-21·8] of 26 patients; p=0·99). The most common grade 3-4 adverse events were dyspnoea (two [8%] in the durvalumab-tremelimumab alone group; three [12%] in the low-dose radiotherapy group; and three [12%] in the hypofractionated radiotherapy group) and hyponatraemia (one [4%] in the durvalumab-tremelimumab alone group vs two [8%] in the low-dose radiotherapy group vs three [12%] in the hypofractionated radiotherapy group). Treatment-related serious adverse events occurred in one (4%) patient in the durvalumab-tremelimumab alone group (maculopapular rash), five (19%) patients in the low-dose radiotherapy group (abdominal pain, diarrhoea, dyspnoea, hypokalemia, and respiratory failure), and four (15%) patients in the hypofractionated group (adrenal insufficiency, colitis, diarrhoea, and hyponatremia). In the low-dose radiotherapy group, there was one death from respiratory failure potentially related to study therapy. INTERPRETATION: Radiotherapy did not increase responses to combined PD-L1 plus CTLA-4 inhibition in patients with NSCLC resistant to PD(L)-1 therapy. However, PD-L1 plus CTLA-4 therapy could be a treatment option for some patients. Future studies should refine predictive biomarkers in this setting. FUNDING: The US National Institutes of Health and the Dana-Farber Cancer Institute.

Larotrectinib Treatment for Patients With TRK Fusion-Positive Salivary Gland Cancers.

BACKGROUND: Larotrectinib is a first-in-class, highly selective, and central nervous system-active tropomyosin receptor kinase (TRK) inhibitor approved for the treatment of adult and pediatric patients with TRK fusion cancer. We report the efficacy and safety of larotrectinib in patients with TRK fusion-positive salivary gland cancers. PATIENTS AND METHODS: Patients with TRK fusion-positive salivary gland cancer treated with larotrectinib were identified from two clinical trials (NCT02122913 and NCT02576431). Patients received larotrectinib 100 mg twice daily (BID) except for one patient who received 150 mg BID in the phase I trial. The primary endpoint was objective response rate (ORR) as assessed by the investigator using Response Evaluation Criteria in Solid Tumors version 1.1. RESULTS: At the data cut-off (July 20, 2020), 24 patients with TRK fusion-positive salivary gland cancer had been treated. The most common histologies were secretory carcinoma (54%), adenocarcinoma (25%), and mucoepidermoid carcinoma (13%). All 24 patients had an ETV6-NTRK3 gene fusion. The ORR was 92% (95% confidence interval, 73-99). Best overall response was complete response in three (13%) patients, partial response in 19 (79%), and progressive disease in two (8%). The rate of progression-free survival at 24 months was 78% (median follow-up 30.9 months). Most treatment-related adverse events (AEs) were grade 1-2, and no patients discontinued treatment due to AEs. CONCLUSION: Larotrectinib demonstrated robust and durable efficacy in patients with TRK fusion-positive salivary gland tumors of various histologies, and a favorable safety profile. These findings support NTRK gene fusion testing in patients with advanced salivary gland cancers. CLINICALTRIALS.GOV NUMBERS: NCT02122913 and NCT02576431.

Ehrlichia type IV secretion system effector Etf-2 binds to active RAB5 and delays endosome maturation.

Ehrlichia chaffeensis, an obligatory intracellular bacterium, infects monocytes/macrophages by sequestering a regulator of endosomal traffic, the small GTPase RAB5, on its membrane-bound inclusions to avoid routing to host-cell phagolysosomes. How RAB5 is sequestered on ehrlichial inclusions is poorly understood, however. We found that native Ehrlichia translocated factor-2 (Etf-2), a previously predicted effector of the Ehrlichia type IV secretion system, and recombinant Etf-2 (cloned into the Ehrlichia genome) are secreted into the host-cell cytoplasm and localize to ehrlichial inclusions. Ectopically expressed Etf-2-GFP also localized to inclusions and membranes of early endosomes marked with RAB5 and interacted with GTP-bound RAB5 but not with a GDP-bound RAB5. Etf-2, although lacking a RAB GTPase-activating protein (GAP) Tre2-Bub2-Cdc16 (TBC) domain, contains two conserved TBC domain motifs, namely an Arg finger and a Gln finger, and site-directed mutagenesis revealed that both Arg188 and Gln245 are required for Etf-2 localization to early endosomes. The yeast two-hybrid assay and microscale thermophoresis revealed that Etf-2 binds tightly to GTP-bound RAB5 but not to GDP-bound RAB5. However, Etf-2 lacks RAB5-specific GAP activity. Etf-2 localized to bead-containing phagosomes as well as endosomes containing beads coated with the C-terminal fragment of EtpE (entry-triggering protein of Ehrlichia), an Ehrlichia outer-membrane invasin, and significantly delayed RAB5 dissociation from and RAB7 localization to phagosomes/endosomes and RABGAP5 localization to endosomes. Thus, binding of Etf-2 to RAB5-GTP appears to delay RAB5 inactivation by impeding RABGAP5 localization to endosomes. This suggests a unique mechanism by which RAB5 is sequestered on ehrlichial inclusions to benefit bacterial survival and replication.

Expression and purification of human and Saccharomyces cerevisiae equilibrative nucleoside transporters.

Nucleosides play an essential role in the physiology of eukaryotes by acting as metabolic precursors in de novo nucleic acid synthesis and energy metabolism. Nucleosides also act as ligands for purinergic receptors. Equilibrative nucleoside transporters (ENTs) are polytopic integral membrane proteins that aid in regulating plasmalemmal flux of purine and pyrimidine nucleosides and nucleobases. ENTs exhibit broad substrate selectivity across different isoforms and utilize diverse mechanisms to drive substrate flux across membranes. However, the molecular mechanisms and chemical determinants of ENT-mediated substrate recognition, binding, inhibition, and transport are poorly understood. To determine how ENT-mediated transport occurs at the molecular level, greater chemical insight and assays employing purified protein are essential. This article focuses on the expression and purification of human ENT1, human ENT2, and Saccharomyces cerevisiae ScENT1 using novel expression and purification strategies to isolate recombinant ENTs. ScENT1, hENT1, and hENT2 were expressed in W303 Saccharomyces cerevisiae cells and detergent solubilized from the membrane. After detergent extraction, these ENTs were further purified using immobilized metal affinity chromatography and size exclusion chromatography. This effort resulted in obtaining quantities of purified protein sufficient for future biophysical analysis.

Functional Characterization of the Saccharomyces cerevisiae Equilibrative Nucleoside Transporter 1 (ScENT1).

Equilibrative nucleoside transporters (ENTs) are polytopic membrane transporters responsible for the translocation of nucleosides, nucleobases-to a lesser extent-and nucleoside analog therapeutics across cellular membranes. ENTs function in a diffusion controlled bidirectional manner and are thought to utilize an alternating access transport mechanism. However, a detailed understanding of ENT function at the molecular level has remained elusive. ScENT1 (formerly known as Function Unknown Now 26 or FUN26) is the only known ENT ortholog endogenously expressed in S. cerevisiae, and a proteoliposome assay system was used to study homogenously overexpressed and purified ScENT1 (wildtype relative to L390A and F249I mutants). L390 and F249 are highly conserved residues and were found to alter transporter function. L390A produced a reduction of mean transport activity while F249I increased mean substrate translocation relative to wildtype protein. However, both mutations resulted in transport of UTP-a novel gain of function for any ENT. These residues were then mapped onto an ab initio model of FUN26 which suggests they function in substrate translocation (L390) or cytoplasmic gating (F249). Furthermore, wildtype, L390A, and F249I were found to be sensitive to the presence of alcohols. Ethanol attenuated ScENT1-mediated transport of uridine by ~50%. These findings further demonstrate functional similarities between ScENT1 and human ENT isoforms and support identification of FUN26 as ScENT1, the first ENT isoform in S. cerevisiae.

Conformation-Dependent Human p52Shc Phosphorylation by Human c-Src.

Phosphorylation of the human p52Shc adaptor protein is a key determinant in modulating signaling complex assembly in response to tyrosine kinase signaling cascade activation. The underlying mechanisms that govern p52Shc phosphorylation status are unknown. In this study, p52Shc phosphorylation by human c-Src was investigated using purified proteins to define mechanisms that affect the p52Shc phosphorylation state. We conducted biophysical characterizations of both human p52Shc and human c-Src in solution as well as membrane-mimetic environments using the acidic lipid phosphatidylinositol 4-phosphate or a novel amphipathic detergent (2,2-dihexylpropane-1,3-bis-ß-D-glucopyranoside). We then identified p52Shc phosphorylation sites under various solution conditions, and the amount of phosphorylation at each identified site was quantified using mass spectrometry. These data demonstrate that the p52Shc phosphorylation level is altered by the solution environment without affecting the fraction of active c-Src. Mass spectrometry analysis of phosphorylated p52Shc implies functional linkage among phosphorylation sites. This linkage may drive preferential coupling to protein binding partners during signaling complex formation, such as during initial binding interactions with the Grb2 adaptor protein leading to activation of the Ras/MAPK signaling cascade. Remarkably, tyrosine residues involved in Grb2 binding were heavily phosphorylated in a membrane-mimetic environment. The increased phosphorylation level in Grb2 binding residues was also correlated with a decrease in the thermal stability of purified human p52Shc. A schematic for the phosphorylation-dependent interaction between p52Shc and Grb2 is proposed. The results of this study suggest another possible therapeutic strategy for altering protein phosphorylation to regulate signaling cascade activation.

FUN26 (function unknown now 26) protein from saccharomyces cerevisiae is a broad selectivity, high affinity, nucleoside and nucleobase transporter.

Equilibrative nucleoside transporters (ENTs) are polytopic integral membrane proteins that transport nucleosides and, to a lesser extent, nucleobases across cell membranes. ENTs modulate efficacy for a range of human therapeutics and function in a diffusion-controlled bidirectional manner. A detailed understanding of ENT function at the molecular level has remained elusive. FUN26 (function unknown now 26) is a putative ENT homolog from S. cerevisiae that is expressed in vacuole membranes. In the present system, proteoliposome studies of purified FUN26 demonstrate robust nucleoside and nucleobase uptake into the luminal volume for a broad range of substrates. This transport activity is sensitive to nucleoside modifications in the C(2')- and C(5')-positions on the ribose sugar and is not stimulated by a membrane pH differential. [(3)H]Adenine nucleobase transport efficiency is increased ∼4-fold relative to nucleosides tested with no observed [(3)H]adenosine or [(3)H]UTP transport. FUN26 mutational studies identified residues that disrupt (G463A or G216A) or modulate (F249I or L390A) transporter function. These results demonstrate that FUN26 has a unique substrate transport profile relative to known ENT family members and that a purified ENT can be reconstituted in proteoliposomes for functional characterization in a defined system.

Overproduction and biophysical characterization of human HSP70 proteins.

Heat shock proteins (HSP) perform vital cellular functions and modulate cell response pathways to physical and chemical stressors. A key feature of HSP function is the ability to interact with a broad array of protein binding partners as a means to potentiate downstream response pathways or facilitate protein folding. These binding interactions are driven by ATP-dependent conformational rearrangements in HSP proteins. The HSP70 family is evolutionarily conserved and is associated with diabetes and cancer progression and the etiopathogenesis of hepatic, cardiovascular, and neurological disorders in humans. However, functional characterization of human HSP70s has been stymied by difficulties in obtaining large quantities of purified protein. Studies of purified human HSP70 proteins are essential for downstream investigations of protein-protein interactions and in the rational design of novel family-specific therapeutics. Within this work, we present optimized protocols for the heterologous overexpression and purification of either the nucleotide binding domain (NBD) or the nucleotide and substrate binding domains of human HSPA9, HSPA8, and HSPA5 in either Escherichia coli or Saccharomyces cerevisiae. We also include initial biophysical characterization of HSPA9 and HSPA8. This work provides the basis for future biochemical studies of human HSP70 protein function and structure.

From Base Pairs to City Squares: Comprehensive Precision Oncology for the Future.

SUMMARY: An increased understanding of the role of the social determinants of health in cancer prevention, cancer care, and outcomes can lead to their integration into genetics and genomics as well as informing interventions and clinical trials, creating a comprehensive precision oncology framework.

A new prognostic model in chemotherapy-treated patients with recurrent or metastatic head and neck cancer: An analysis of ECOG-ACRIN E1305.

INTRODUCTION: For patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M HNSCC) periodic reassessment of prognostic factors provides valuable information that can aid in patient stratification. PATIENTS AND METHODS: This post hoc analysis included all patients with R/M HNSCC enrolled in the ECOG-ACRIN E1305 phase III clinical trial who received first-line treatment with platinum-containing chemotherapy doublet with or without bevacizumab. Overall survival (OS) was estimated using the Kaplan-Meier method. Prognostic factors for OS were identified using univariate and multivariable analyses. A new prognostic model for OS was built retaining the prognostic factors which were significant in the final multivariable analysis (P < 0.05). RESULTS: All 403 study participants were included in the analysis. The median OS in the whole study cohort was 11.8 months (90% confidence intervals [CI], 10.6-13.2). The new prognostic model for OS comprised four risk factors (ECOG performance status [1 versus 0], primary tumor location [other versus oropharynx], presence of bone or liver metastasis, and prior radiation to the head and neck); patients with ≤ 2 (n = 249) and > 2 risk factors (n = 154) had a median OS of 15.2 and 7.6 months, respectively (Hazard ratio, 2.14; 95% CI, 1.73-2.66; P < 0.0001). CONCLUSIONS: The new proposed model includes 4 clinical prognostic factors that can be readily assessed at baseline. Similar models have the potential to improve trial design and optimize stratification of patients with R/M HNSCC.

Molecular Profiling and the Impact of Treatment on Outcomes in Adenoid Cystic Carcinoma Type I and II.

PURPOSE: Adenoid cystic carcinoma (ACC) is an uncommon salivary gland cancer with no approved therapies available to treat advanced, incurable disease. Recent molecular profiling efforts have identified two important subtypes: the more aggressive ACC-I is characterized by Notch pathway alterations and MYC amplification whereas ACC-II demonstrates a more indolent phenotype and TP63 overexpression. EXPERIMENTAL DESIGN: This retrospective observational cohort study involved de-identified samples from 438 patients with ACC with tumor samples sent for commercially-available molecular profiling (Caris Life Sciences). Next-generation whole-exome and whole-transcriptomic sequencing was performed on primary and metastatic samples. Immunostaining for PD-L1 and RNA deconvolution (quanTIseq) was used to explore the tumor immune microenvironment (TME). Real-world clinical and survival outcome metrics were extracted from insurance claims data. RESULTS: MYC expression was 1.61-fold higher (39.8 vs. 24.7; P < 0.0001) among NOTCH1-mutant ACC-I tumors, whereas MYB/L1 fusion rates were similar among ACC-I/II. The median B-cell fraction in the TME was higher among ACC-II (7.1% vs. 5.8%; P < 0.01), although infiltrating T cells subsets were low among either ACC subgroup (both <1%). When pooling systemic treatment categories, ACC-I patients had worse outcomes with available therapies (HR, 3.06; 95% confidence interval, 1.65-5.68; P < 0.01), with no significant difference in overall survival between ACC-I/II based on chemotherapy or VEGFR tyrosine kinase inhibitor exposure in smaller subsets. CONCLUSIONS: We confirmed the previously reported associations with MYC and TP63 in the prognostically relevant subgroups of ACC-I and -II, respectively, and report immunologic differences among these subtypes. Survival outcomes are comparatively worse in ACC-I regardless of treatment type.

Predictive capacity of immune-related adverse events and cytokine profiling in neoadjuvant immune checkpoint inhibitor trials for head and neck squamous cell carcinoma.

OBJECTIVES: Certain low-level immune-related adverse events (irAEs) have been associated with survival benefits in patients with various solid tumors on immune checkpoint inhibitors (ICIs). We aimed to investigate the association between irAEs and response to neoadjuvant ICIs in patients with head and neck squamous cell carcinoma (HNSCC) and to identify differences in circulating cytokine levels based on irAE status. METHODS: This was a retrospective cohort study including three neoadjuvant clinical trials from July 2017 to January 2022: NCT03238365 (nivolumab ± tadalafil), NCT03854032 (nivolumab ± BMS986205), NCT03618654 (durvalumab ± metformin). The presence and type of irAEs, pathologic treatment response, and survival were compared. Canonical linear discriminant analysis (LDA) was performed to identify combinations of circulating cytokines predictive of irAEs using plasma sample multiplex assay. RESULTS: Of 113 participants meeting inclusion criteria, 32 (28.3%) developed irAEs during treatment or follow-up. Positive p16 status was associated with irAEs (odds ratio [OR] 2.489; 95% CI 1.069-6.119; p = 0.043). irAEs were associated with pathologic treatment response (OR 3.73; 95% CI 1.34-10.35; p = 0.011) and with higher OS in the combined cohort (HR 0.319; 95% CI 0.113-0.906; p = 0.032). Patients with irAEs within the nivolumab cohort had significant elevations of select cytokines pre-treatment. Canonical LDA identified key drivers of irAEs among all trials, which were highly predictive of future irAE status. CONCLUSIONS: irAEs are associated with response to neoadjuvant ICI therapy in HNSCC and can serve as clinical indicators for improved clinical outcomes. irAEs can be predicted by concentrations of several circulating cytokines prior to treatment.

Comprehensive peripheral blood immunoprofiling reveals five immunotypes with immunotherapy response characteristics in patients with cancer.

The lack of comprehensive diagnostics and consensus analytical models for evaluating the status of a patient's immune system has hindered a wider adoption of immunoprofiling for treatment monitoring and response prediction in cancer patients. To address this unmet need, we developed an immunoprofiling platform that uses multiparameter flow cytometry to characterize immune cell heterogeneity in the peripheral blood of healthy donors and patients with advanced cancers. Using unsupervised clustering, we identified five immunotypes with unique distributions of different cell types and gene expression profiles. An independent analysis of 17,800 open-source transcriptomes with the same approach corroborated these findings. Continuous immunotype-based signature scores were developed to correlate systemic immunity with patient responses to different cancer treatments, including immunotherapy, prognostically and predictively. Our approach and findings illustrate the potential utility of a simple blood test as a flexible tool for stratifying cancer patients into therapy response groups based on systemic immunoprofiling.

Skp1 prolyl 4-hydroxylase of dictyostelium mediates glycosylation-independent and -dependent responses to O2 without affecting Skp1 stability.

Cytoplasmic prolyl 4-hydroxylases (PHDs) have a primary role in O(2) sensing in animals via modification of the transcriptional factor subunit HIFα, resulting in its polyubiquitination by the E3(VHL)ubiquitin (Ub) ligase and degradation in the 26 S proteasome. Previously thought to be restricted to animals, a homolog (P4H1) of HIFα-type PHDs is expressed in the social amoeba Dictyostelium where it also exhibits characteristics of an O(2) sensor for development. Dictyostelium lacks HIFα, and P4H1 modifies a different protein, Skp1, an adaptor of the SCF class of E3-Ub ligases related to the E3(VHL)Ub ligase that targets animal HIFα. Normally, the HO-Skp1 product of the P4H1 reaction is capped by a GlcNAc sugar that can be subsequently extended to a pentasaccharide by novel glycosyltransferases. To analyze the role of glycosylation, the Skp1 GlcNAc-transferase locus gnt1 was modified with a missense mutation to block catalysis or a stop codon to truncate the protein. Despite the accumulation of the hydroxylated form of Skp1, Skp1 was not destabilized based on metabolic labeling. However, hydroxylation alone allowed for partial correction of the high O(2) requirement of P4H1-null cells, therefore revealing both glycosylation-independent and glycosylation-dependent roles for hydroxylation. Genetic complementation of the latter function required an enzymatically active form of Gnt1. Because the effect of the gnt1 deficiency depended on P4H1, and Skp1 was the only protein labeled when the GlcNAc-transferase was restored to mutant extracts, Skp1 apparently mediates the cellular functions of both P4H1 and Gnt1. Although Skp1 stability itself is not affected by hydroxylation, its modification may affect the stability of targets of Skp1-dependent Ub ligases.

Nucleotide excision repair deficiency is intrinsic in sporadic stage I breast cancer.

The molecular etiology of breast cancer has proven to be remarkably complex. Most individual oncogenes are disregulated in only approximately 30% of breast tumors, indicating that either very few molecular alterations are common to the majority of breast cancers, or that they have not yet been identified. In striking contrast, we now show that 19 of 19 stage I breast tumors tested with the functional unscheduled DNA synthesis assay exhibited a significant deficiency of DNA nucleotide excision repair (NER) capacity relative to normal epithelial tissue from disease-free controls (n = 23). Loss of DNA repair capacity, including the complex, damage-comprehensive NER pathway, results in genomic instability, a hallmark of carcinogenesis. By microarray analysis, mRNA expression levels for 20 canonical NER genes were reduced in representative tumor samples versus normal. Significant reductions were observed in 19 of these genes analyzed by the more sensitive method of RNase protection. These results were confirmed at the protein level for five NER gene products. Taken together, these data suggest that NER deficiency may play an important role in the etiology of sporadic breast cancer, and that early-stage breast cancer may be intrinsically susceptible to genotoxic chemotherapeutic agents, such as cis-platinum, whose damage is remediated by NER. In addition, reduced NER capacity, or reduced expression of NER genes, could provide a basis for the development of biomarkers for the identification of tumorigenic breast epithelium.

Nivolumab and ipilimumab in combination with radiotherapy in patients with high-risk locally advanced squamous cell carcinoma of the head and neck.

BACKGROUND: The combination of nivolumab and ipilimumab has been approved for the treatment of multiple solid tumors. This was a phase I study investigating definitive radioimmunotherapy (RIT) with nivolumab and ipilimumab for the treatment of locally advanced (LA) squamous cell carcinoma of the head and neck (SCCHN). METHODS: Patients with newly diagnosed, stage IVA-IVB SCCHN eligible for cisplatin-based chemotherapy received nivolumab (3 mg/kg every 2 weeks for a total of 17 doses) and ipilimumab (1 mg/kg every 6 weeks for a total of 6 doses) starting 2 weeks prior to radiotherapy. The primary endpoint was safety of definitive RIT. Secondary endpoints included progression-free survival (PFS) and overall survival (OS). Exploratory endpoints included the association of baseline programmed death-ligand 1 (PD-L1) expression as well as on-treatment changes in immune bias with treatment outcomes. RESULTS: Twenty-four patients were enrolled. With a median follow-up of 36.1 months, grade 3 or higher treatment-related adverse events were reported in 21 individuals (88%); 5 individuals developed in-field soft tissue ulceration during consolidation immunotherapy, resulting in one fatality. The 3-year PFS and OS rates were 74% (95% CI 58% to 94%) and 96% (95% CI 88% to 100%), respectively. PD-L1 combined positive score (CPS) did not correlate with death or disease progression. Decreases in extracellular vesicle PD-L1 within the concurrent RIT phase were associated with prolonged PFS (p=0.006). Also, interval decreases in circulating interleukin (IL)4, IL9, IL12, and IL17a during concurrent RIT were associated with subsequent ulceration. CONCLUSIONS: Definitive RIT with nivolumab and ipilimumab has sufficient clinical activity to support further development. Early changes in circulating biomarkers appear able to predict treatment outcomes as well as ensuing in-field soft tissue ulceration. TRIAL REGISTRATION NUMBER: NCT03162731.

Molecular lung cancer: How targeted therapies and personalized medicine are re-defining cancer care.

Lung cancer remains the leading cause of cancer death in the United States and is unfortunately still frequently diagnosed in the metastatic setting, where the disease is considered incurable. Nearly 30% of these cancers may be driven by specific mutations that promote tumor growth and proliferation. These mutations are observed more frequently in young patients without significant smoking history and in certain racial and ethnic backgrounds. The past 15 years have marked a revolution for patients with molecularly driven lung cancer as novel, oral, targeted therapies have been developed that demonstrate superior activity with substantially better toxicity profiles in comparison to chemotherapy. Consideration of molecular testing for a driver mutation is imperative for all providers caring for patients with a new suspected lung cancer diagnosis, as discovery of an actionable mutation will have dramatic implications in regards to patient survival and quality of life.