New and Promising Targeted Therapies in First and Second-Line Settings

AbstractDeeper understanding of the molecular pathogenesis of malignancies, including head and neck squamous cell carcinoma (HNSCC), has led to the investigation of several novel targeted therapies. These therapeutic approaches may eventually replace or complement existing treatment modalities, such as surgery, radiation therapy, and traditional cytotoxic chemotherapy. Epidermal growth factor receptor (EGFR) inhibitors, and specifically cetuximab, are as of now the only class of targeted agents, excluding immune checkpoint inhibitors, with approval in the treatment of HNSCC. Beyond EGFR inhibition, novel therapies under evaluation are directed against vascular endothelial growth factor (VEGF) and VEGF receptor (VEGFR), PI3K/AKT/mTOR pathway, cell cycle regulation (for example, cyclin dependent kinases 4 and 6), HRAS, DNA repair mechanisms, and others. Development of new therapies has to take into consideration the complexity of solid tumors and their heterogeneity. Multitargeted combination therapy approaches may be required in certain cases in order to maximize antitumor effect. Ways to individualize treatment using validated biomarkers are likely to improve outcomes. We review the most relevant molecular targets in HNSCC and provide updates on clinical trial data with promising new targeted agents

Maackia Amurensis Seed Lectin (MASL) and soluble human podoplanin (shPDPN) Sequence Analysis and Effects on Human Oral Squamous Cell Carcinoma (OSCC) Cell Migration and Viability

Maackia amurensis lectins serve as research and botanical agents that bind to sialic residues on proteins. For example, M. amurensis seed lectin (MASL) targets the sialic acid modified podoplanin (PDPN) receptor to suppress arthritic chondrocyte inflammation, and inhibit tumor cell growth and motility. However, M. amurensis lectin nomenclature and composition are not clearly defined. Here, we sought to definitively characterize MASL and its effects on tumor cell behavior. We utilized SDS-PAGE and LC-MS/MS to find that M. amurensis lectins can be divided into two groups. MASL is a member of one group which is composed of subunits that form dimers, evidently mediated by a cysteine residue in the carboxy region of the protein. In contrast to MASL, members of the other group do not dimerize under nonreducing conditions. These data also indicate that MASL is composed of 4 isoforms with an identical amino acid sequence, but unique glycosylation sites. We also produced a novel recombinant soluble human PDPN receptor (shPDPN) with 17 threonine residues glycosylated with sialic acid moieties with potential to act as a ligand trap that inhibits OSCC cell growth and motility. In addition, we report here that MASL targets PDPN with very strong binding kinetics in the nanomolar range. Moreover, we confirm that MASL can inhibit the growth and motility of human oral squamous cell carcinoma (OSCC) cells that express the PDPN receptor. Taken together, these data characterize M. amurensis lectins into two major groups based on their intrinsic properties, clarify the composition of MASL and its subunit isoform sequence and glycosylation sites, define sialic acid modifications on the PDPN receptor and its ability to act as a ligand trap, quantitate MASL binding to PDPN with KD in the nanomolar range, and verify the ability of MASL to serve as a potential anticancer agent

Identification and Functional Characterization of G6PC2 Coding Variants Influencing Glycemic Traits Define an Effector Transcript at the G6PC2-ABCB11 Locus

Genome wide association studies (GWAS) for fasting glucose (FG) and insulin (FI) have identified common variant signals which explain 4.8% and 1.2% of trait variance, respectively. It is hypothesized that low-frequency and rare variants could contribute substantially to unexplained genetic variance. To test this, we analyzed exome-array data from up to 33,231 non-diabetic individuals of European ancestry. We found exome-wide significant (P&lt;5×10-7) evidence for two loci not previously highlighted by common variant GWAS: GLP1R (p.Ala316Thr, minor allele frequency (MAF)=1.5%) influencing FG levels, and URB2 (p.Glu594Val, MAF = 0.1%) influencing FI levels. Coding variant associations can highlight potential effector genes at (non-coding) GWAS signals. At the G6PC2/ABCB11 locus, we identified multiple coding variants in G6PC2 (p.Val219Leu, p.His177Tyr, and p.Tyr207Ser) influencing FG levels, conditionally independent of each other and the non-coding GWAS signal. In vitro assays demonstrate that these associated coding alleles result in reduced protein abundance via proteasomal degradation, establishing G6PC2 as an effector gene at this locus. Reconciliation of single-variant associations and functional effects was only possible when haplotype phase was considered. In contrast to earlier reports suggesting that, paradoxically, glucose-raising alleles at this locus are protective against type 2 diabetes (T2D), the p.Val219Leu G6PC2 variant displayed a modest but directionally consistent association with T2D risk. Coding variant associations for glycemic traits in GWAS signals highlight PCSK1, RREB1, and ZHX3 as likely effector transcripts. These coding variant association signals do not have a major impact on the trait variance explained, but they do provide valuable biological insights.</p

Sequence data and association statistics from 12,940 type 2 diabetes cases and controls

To investigate the genetic basis of type 2 diabetes (T2D) to high resolution, the GoT2D and T2D-GENES consortia catalogued variation from whole-genome sequencing of 2,657 European individuals and exome sequencing of 12,940 individuals of multiple ancestries. Over 27M SNPs, indels, and structural variants were identified, including 99% of low-frequency (minor allele frequency [MAF] 0.1–5%) non-coding variants in the whole-genome sequenced individuals and 99.7% of low-frequency coding variants in the whole-exome sequenced individuals. Each variant was tested for association with T2D in the sequenced individuals, and, to increase power, most were tested in larger numbers of individuals (>80% of low-frequency coding variants in ~82 K Europeans via the exome chip, and ~90% of low-frequency non-coding variants in ~44 K Europeans via genotype imputation). The variants, genotypes, and association statistics from these analyses provide the largest reference to date of human genetic information relevant to T2D, for use in activities such as T2D-focused genotype imputation, functional characterization of variants or genes, and other novel analyses to detect associations between sequence variation and T2D

The genetic architecture of type 2 diabetes

The genetic architecture of common traits, including the number, frequency, and effect sizes of inherited variants that contribute to individual risk, has been long debated. Genome-wide association studies have identified scores of common variants associated with type 2 diabetes, but in aggregate, these explain only a fraction of heritability. To test the hypothesis that lower-frequency variants explain much of the remainder, the GoT2D and T2D-GENES consortia performed whole genome sequencing in 2,657 Europeans with and without diabetes, and exome sequencing in a total of 12,940 subjects from five ancestral groups. To increase statistical power, we expanded sample size via genotyping and imputation in a further 111,548 subjects. Variants associated with type 2 diabetes after sequencing were overwhelmingly common and most fell within regions previously identified by genome-wide association studies. Comprehensive enumeration of sequence variation is necessary to identify functional alleles that provide important clues to disease pathophysiology, but large-scale sequencing does not support a major role for lower-frequency variants in predisposition to type 2 diabetes

Erratum: Sequence data and association statistics from 12,940 type 2 diabetes cases and controls

Scientific Data 4:170179 doi: 10.1038/sdata.2017.179 (2017); Published 19 December 2017; Updated: 23 January 2018. In both the HTML and PDF versions of this Data Descriptor, the author name Jason Flannick was incorrectly listed as Flannick Jason.</jats:p

Neck Dissection and Survival Among Head and Neck Cancer Patients Undergoing Adjuvant Immunotherapy

ABSTRACT Background Some studies suggest that neck dissection (ND) should be avoided in candidates for immunotherapy because lymph nodes are primary sites for immunotherapy activation. Our study investigates ND utilization and associated differences in overall survival (OS) among patients with head and neck cancer (HNC) undergoing adjuvant immunotherapy. Methods The 2013–2018 National Cancer Database was retrospectively reviewed for patients with HNC undergoing surgery with curative intent, and adjuvant immunotherapy. Multivariable binary logistic and Cox regression models adjusted for patient demographics, clinicopathologic features, and treatment. Results Of 1335 patients satisfying inclusion criteria, 679 (50.9%) patients underwent ND: 94 (13.8%) had pN0, 109 (16.1%) had pN1, 411 (60.5%) had pN2, 60 (8.8%) had pN3, and 5 (0.7%) had pNx classification. On multivariable binary logistic regression, academic treatment facility, cT4, and cN1–3 classification were associated with higher odds of undergoing ND (p < 0.05); salivary, sinonasal, oropharyngeal, hypopharyngeal, and laryngeal primary sites were associated with decreased odds (p < 0.05). Compared with those undergoing neck observation, patients undergoing ND had worse OS (49.4% vs. 61.5%, p < 0.001) on Kaplan–Meier but not multivariable Cox (adjusted hazard ratio [aHR] 1.00, 95% confidence interval [CI] 0.82–1.24, p = 0.968) regression. Compared with adjuvant immunotherapy alone, the addition of radiotherapy (aHR 0.64, 95% CI 0.44–0.93) and chemoradiotherapy (aHR 0.56, 95% CI 0.37–0.86) were associated with higher OS (p < 0.025). Conclusion ND was utilized in approximately 51% of patients with HNC undergoing adjuvant immunotherapy. ND was not associated with worse OS, possibly related to the high rate of pN1–3 classification. Level of Evidence

Detection of C4d Deposition in Cardiac Allografts: A Comparative Study of Immunofluorescence and Immunoperoxidase Methods

Abstract Context.—Complement activation, evidenced by deposition of C4d, is important in the diagnosis of antibody-mediated rejection of cardiac allografts. C4d deposition can be assessed by either immunofluorescence (IF)– or immunoperoxidase (IP)–based methods. The use of methods varies considerably among institutions, but there are few data addressing their diagnostic equivalence. Objective.—To compare IF and IP C4d staining on paired endomyocardial biopsy samples from a large number of heart transplant patients. Design.—Retrospectively selected paired frozen and paraffin-embedded samples from the same biopsy were stained for C4d by IF and IP methods. Capillary staining was scored by using a 0, 1+, 2+, 3+ scale. Results.—A total of 296 biopsy pairs from 70 patients were studied. There were two hundred forty-three cases that were scored 0, twenty-four scored 1+, sixteen scored 2+, and thirteen scored 3+ by IF. Two hundred thirty-one cases scored 0, forty scored 1+, ten scored 2+, and fifteen scored 3+ by IP. Complete agreement was seen in 81% of cases. Among discrepant cases, 89% (n  =  51) were minor (±1) and 11% (n  =  6) were major (±2). Five of the 6 major discrepancy biopsies came from 2 patients, both of whom had concordant (IF and IP) 3+ results on prior biopsies. The weighted κ value for the entire sample set was 0.78 and for the first biopsy only set (to correct for bias introduced by multiple biopsies from the same patient) the weighted κ value was 0.88. Conclusions.—Immunofluorescence and IP C4d staining methods are highly comparable and are both viable options for antibody-mediated rejection surveillance in transplant heart biopsies.</jats:p