Identification of genomic mutations associated with clinical outcomes of induction chemotherapy in patients with head and neck squamous cell carcinoma

Molecular and biological factors in the prognosis of head and neck squamous cell cancer

The objective of the review is to summarize available literary data on the role and prognostic value of molecular biological markers p53, UBE2C, CD147, STAT3, VEGF in the carcinogenesis of head and neck squamous cell carcinoma (HNSCC). To date, researches have been studying HNSCC molecular and genetic characteristics and obtaining information about new molecular biological markers that have different functional significance in tumor progression. This review presents current data on protein molecules involved in the HNSCC development, as well as in the formation of drug resistance mechanisms in tumors. The considered markers can be used not only for prognosis but also for developing a new approach to treatment, including patients resistant to therapy or recurrent HNSCC. However, the introduction of these markers into practice requires further examination of their functions and larger-scale studies.

Circulating tumour DNA alterations: emerging biomarker in head and neck squamous cell carcinoma

Head and Neck cancers (HNC) are a heterogeneous group of upper aero-digestive tract cancer and account for 931,922 new cases and 467,125 deaths worldwide. About 90% of these cancers are of squamous cell origin (HNSCC). HNSCC is associated with excessive tobacco and alcohol consumption and infection with oncogenic viruses. Genotyping tumour tissue to guide clinical decision-making is becoming common practice in modern oncology, but in the management of patients with HNSCC, cytopathology or histopathology of tumour tissue remains the mainstream for diagnosis and treatment planning. Due to tumour heterogeneity and the lack of access to tumour due to its anatomical location, alternative methods to evaluate tumour activities are urgently needed. Liquid biopsy approaches can overcome issues such as tumour heterogeneity, which is associated with the analysis of small tissue biopsy. In addition, liquid biopsy offers repeat biopsy sampling, even for patients with tumours with access limitations. Liquid biopsy refers to biomarkers found in body fluids, traditionally blood, that can be sampled to provide clinically valuable information on both the patient and their underlying malignancy. To date, the majority of liquid biopsy research has focused on blood-based biomarkers, such as circulating tumour DNA (ctDNA), circulating tumour cells (CTCs), and circulating microRNA. In this review, we will focus on ctDNA as a biomarker in HNSCC because of its robustness, its presence in many body fluids, adaptability to existing clinical laboratory-based technology platforms, and ease of collection and transportation. We will discuss mechanisms of ctDNA release into circulation, technological advances in the analysis of ctDNA, ctDNA as a biomarker in HNSCC management, and some of the challenges associated with translating ctDNA into clinical and future perspectives. ctDNA provides a minimally invasive method for HNSCC prognosis and disease surveillance and will pave the way in the future for personalized medicine, thereby significantly improving outcomes and reducing healthcare costs.

Induction chemotherapy in locally advanced head and neck cancers, is there a best choice?

Locally advanced stages of squamous cancers of the head and neck (LAHNCs) acquire high propensity for local and systemic relapse. Addition of systemic therapy as an induction (IC) to the standard concurrent chemoradiotherapy (CCRT) has become an approach of many practitioners. This strategy has shown to reduce metastases but did not affect survival in unselected populations. Meanwhile, the induction regimen including docetaxel, cisplatin, 5-FU (TPF) has shown superiority over other combinations, however, a survival advantage was not detected when compared to CCRT alone. This may be attributed to its high toxicity profile, inducing treatment delay, resistance, or variations in tumor sites and responses. Currently, newer systemic therapy combinations are being tested and indicators of benefit are being identified. The focus of this review is on the development of the choice of combination regimen for induction. Subsequently, proposed alternatives and strategies for patient selection will be introduced.

The utility of diffusion-weighted T2 mapping for the prediction of histological tumor grade in patients with head and neck squamous cell carcinoma

Background

In head and neck cancers, histopathological information is important for the determination of the tumor characteristics and for predicting the prognosis. The aim of this study was to assess the utility of diffusion-weighted T2 (DW-T2) mapping for the evaluation of tumor histological grade in patients with head and neck squamous cell carcinoma (SCC).

Methods

The cases of 41 patients with head and neck SCC (21 well/moderately and 17 poorly differentiated SCC) were retrospectively analyzed. All patients received MR scanning using a 3-Tesla MR unit. The conventional T2 value, DW-T2 value, ratio of DW-T2 value to conventional T2 value, and apparent diffusion coefficient (ADC) were calculated using signal information from the DW-T2 mapping sequence with a manually placed region of interest (ROI).

Results

ADC values in the poorly differentiated SCC group were significantly lower than those in the moderately/well differentiated SCC group (P<0.05). The ratio of DW-T2 value to conventional T2 value was also significantly different between poorly and moderately/well differentiated SCC groups (P<0.01). Receiver operating characteristic (ROC) curve analysis of ADC values showed a sensitivity of 0.76, specificity of 0.67, positive predictive value (PPV) of 0.62, negative predictive value (NPV) of 0.8, accuracy of 0.71 and area under the curve (AUC) of 0.73, whereas the ROC curve analysis of the ratio of DW-T2 value to conventional T2 value showed a sensitivity of 0.76, specificity of 0.83, PPV of 0.76, NPV of 0.83, accuracy of 0.8 and AUC of 0.82.

Conclusions

DW-T2 mapping might be useful as supportive information for the determination of tumor histological grade in patients with head and neck SCC.

Clinical significance of FBXW7 loss of function in human cancers

FBXW7 (F-Box and WD Repeat Domain Containing 7) (also referred to as FBW7 or hCDC4) is a component of the Skp1-Cdc53 / Cullin-F-box-protein complex (SCF/β-TrCP). As a member of the F-box protein family, FBXW7 serves a role in phosphorylation-dependent ubiquitination and proteasome degradation of oncoproteins that play critical role(s) in oncogenesis. FBXW7 affects many regulatory functions involved in cell survival, cell proliferation, tumor invasion, DNA damage repair, genomic instability and telomere biology. This thorough review of current literature details how FBXW7 expression and functions are regulated through multiple mechanisms and how that ultimately drives tumorigenesis in a wide array of cell types. The clinical significance of FBXW7 is highlighted by the fact that FBXW7 is frequently inactivated in human lung, colon, and hematopoietic cancers. The loss of FBXW7 can serve as an independent prognostic marker and is significantly correlated with the resistance of tumor cells to chemotherapeutic agents and poorer disease outcomes. Recent evidence shows that genetic mutation of FBXW7 differentially affects the degradation of specific cellular targets resulting in a distinct and specific pattern of activation/inactivation of cell signaling pathways. The clinical significance of FBXW7 mutations in the context of tumor development, progression, and resistance to therapies as well as opportunities for targeted therapies is discussed.

NOTCH1 signaling promotes protein stability of HER3 through the AKT pathway in squamous cell carcinoma of head and neck

Epidermal growth factor receptor (EGFR) remains the sole druggable molecular target other than the PD1/PD-L1 pathway with meaningful clinical benefit in squamous cell carcinoma of head and neck (SCCHN). Human epidermal growth factor receptor 3 (HER3) confers the resistance to EGFR-targeted treatment in SCCHN. Thus, it is essential to determine the distribution and regulatory mechanisms of HER3 in SCCHN. We explored the prevalence of HER3 expression and its distribution within SCCHN by immunohistochemical staining and clinicopathological correlations were analyzed. The regulatory mechanism of HER3 expression was then dissected in vitro, using RT-PCR, Western blotting, and immunoprecipitation in a set of SCCHN cell lines. Subsequent in vivo validation in the murine model was also performed. We found that concomitant high expression of HER3 and its ligand NRG1 in SCCHN is associated with the increased presence of regional lymphatic metastasis and the majority of HER3 is located on the differentiated tumor cells. Further investigation revealed that HER3 is under positive control of NOTCH1 through transcriptional activation and inhibition of protein degradation through the polyubiquitination machinery via AKT pathway and USP8 deubiquitinating enzyme. In addition, loss of function of NOTCH1 suppresses HER3 expression through increased phosphorylation of serine 473 of AKT in SCCHN cells, and promotes the aggressiveness of the tumor cells. These data indicated that the level of HER3 is regulated by NOTCH1 in SCCHN both transcriptionally and post-translationally, and NOTCH1 is in a higher hierarchy in the regulatory system of the AKT pathway. Since NOTCH1 is inactivated in approximately 10% of SCCHN cases and this aberration strongly impacts the AKT pathway and diminishes HER3, exclusion of patients with NOTCH1-inactivated SCCHN may be beneficial for future clinical trials of HER3-targeting antibodies.

The many facets of Notch signaling in breast cancer: toward overcoming therapeutic resistance

In this review, Nandi et al. revisit the mechanisms by which Notch receptors and ligands contribute to normal mammary gland development and breast tumor progression. The authors also discuss combinatorial approaches aimed at disrupting Notch- and TME-mediated resistance that may improve prognosis in breast cancer patients.

Breast cancer is the second leading cause of cancer-related death in women and is a complex disease with high intratumoral and intertumoral heterogeneity. Such heterogeneity is a major driving force behind failure of current therapies and development of resistance. Due to the limitations of conventional therapies and inevitable emergence of acquired drug resistance (chemo and endocrine) as well as radio resistance, it is essential to design novel therapeutic strategies to improve the prognosis for breast cancer patients. Deregulated Notch signaling within the breast tumor and its tumor microenvironment (TME) is linked to poor clinical outcomes in treatment of resistant breast cancer. Notch receptors and ligands are also important for normal mammary development, suggesting the potential for conserved signaling pathways between normal mammary gland development and breast cancer. In this review, we focus on mechanisms by which Notch receptors and ligands contribute to normal mammary gland development and breast tumor progression. We also discuss how complex interactions between cancer cells and the TME may reduce treatment efficacy and ultimately lead to acquired drug or radio resistance. Potential combinatorial approaches aimed at disrupting Notch- and TME-mediated resistance that may aid in achieving in an improved patient prognosis are also highlighted.

DNA Damage Response during Replication Correlates with CIN70 Score and Determines Survival in HNSCC Patients

Aneuploidy is a consequence of chromosomal instability (CIN) that affects prognosis. Gene expression levels associated with aneuploidy provide insight into the molecular mechanisms underlying CIN. Based on the gene signature whose expression was consistent with functional aneuploidy, the CIN70 score was established. We observed an association of CIN70 score and survival in 519 HNSCC patients in the TCGA dataset; the 15% patients with the lowest CIN70 score showed better survival (p = 0.11), but association was statistically non-significant. This correlated with the expression of 39 proteins of the major repair complexes. A positive association with survival was observed for MSH2, XRCC1, MRE11A, BRCA1, BRCA2, LIG1, DNA2, POLD1, MCM2, RAD54B, claspin, a negative for ERCC1, all related with replication. We hypothesized that expression of these factors leads to protection of replication through efficient repair and determines survival and resistance to therapy. Protein expression differences in HNSCC cell lines did not correlate with cellular sensitivity after treatment. Rather, it was observed that the stability of the DNA replication fork determined resistance, which was dependent on the ATR/CHK1-mediated S-phase signaling cascade. This suggests that it is not the expression of individual DNA repair proteins that causes therapy resistance, but rather a balanced expression and coordinated activation of corresponding signaling cascades.

Worldwide prevalence of PI3K-AKT-mTOR pathway mutations in head and neck cancer: A systematic review and meta-analysis

A systematic review (SR) and meta-analysis were conducted to determine the prevalence of PI3K-AKT-mTOR signaling pathway mutations in patients with head and neck cancer (HNC). Overall, 105 studies comprising 8630 patients and 1306 mutations were selected. The estimated mutations prevalence was 13 % for PIK3CA (95 % confidence interval [CI] = 11-14; I² = 82 %; p < 0.0001), 4% for PTEN (95 % CI = 3-5; I² = 55 %; p < 0.0001), 3% for MTOR (95 % CI = 2-4; I² = 5%; p = 0.40), and 2% for AKT (95 % CI = 1-2; I² = 50 %; p = 0.0001). We further stratified the available data of the participants according to risk factors and tumor characteristics, including HPV infection, tobacco use, alcohol exposure, TNM stage, and histological tumor differentiation, and performed subgroup analysis. We identified significant associations between PI3K-AKT-mTOR pathway-associated mutations and advanced TNM stage (odds ratio [OR] = 0.20; 95 % CI = 0.09-0.44; I² = 71 %; p = 0.0001) and oropharyngeal HPV-positive tumors and PIK3CA mutations (OR = 17.48; 95 % CI = 4.20-72.76; I² = 69 %; p < 0.0002). No associations were found between alcohol and tobacco exposure, and tumor differentiation grade. This SR demonstrated that the PI3K-AKT-mTOR pathway emerges as a potential prognostic factor and could offer a molecular basis for future studies on therapeutic targeting in HNC patients.

Identification of candidate mediators of chemoresponse in breast cancer through therapy-driven selection of somatic variants

Purpose

More than a third of primary breast cancer patients are treated with cytotoxic chemotherapy, typically without guidance from predictive markers. Increased use of neoadjuvant chemotherapy provides opportunities for identification of molecules associated with treatment response, by comparing matched tumour samples before and after therapy. Our hypothesis was that somatic variants of increased prevalence after therapy promote resistance, while variants with reduced prevalence cause sensitivity.

Methods

We performed systematic analyses of matched pairs of cancer exomes from primary oestrogen receptor-positive/HER2-negative breast cancers (n = 6) treated with neoadjuvant epirubicin/cyclophosphamide. We identified candidate genes as mediators of chemotherapy response by consistent subclonal changes in somatic variant prevalence through therapy, predicted variant impact on gene function, and enrichment of specific functional pathways. Influence of candidate genes on breast cancer outcome was tested using publicly available breast cancer expression data (n = 1903).

Results

We identified 14 genes as the strongest candidate mediators of chemoresponse: TCHH, MUC17, ARAP2, FLG2, ABL1, CENPF, COL6A3, DMBT1, ITGA7, PLXNA1, S100PBP, SYNE1, ZFHX4, and CACNA1C. Genes contained somatic variants showing prevalence changes in up to 4 patients, with up to 3 being predicted as damaging. Genes coding for extra-cellular matrix components or related signalling pathways were significantly over-represented among variants showing prevalence changes. Expression of 5 genes (TCHH, ABL1, CENPF, S100PBP, and ZFHX4) was significantly associated with patient survival.

Conclusions

Genomic analysis of paired pre- and post-therapy samples resulting from neoadjuvant therapy provides a powerful method for identification of mediators of response. Genes we identified should be assessed as predictive markers or targets in chemo-sensitization.

Electronic supplementary material

The online version of this article (10.1007/s10549-020-05836-7) contains supplementary material, which is available to authorized users.

Genetic Factors Associated with a Poor Outcome in Head and Neck Cancer Patients Receiving Definitive Chemoradiotherapy

About half of advanced stage head and neck squamous cell carcinoma (HNSCC) patients can be cured by chemoradiotherapy. Patient outcome may be partially determined by the genetic alterations in HNSCC, rendering these alterations promising candidate prognostic factors and/or therapeutic targets. However, their relevance in patient outcome prognosis remains to be assessed in patients that receive standard-of-care chemoradiotherapy. We therefore tested whether frequent genetic alterations were associated with progression free survival (PFS) in advanced stage HNSCC patients who were uniformly treated with definitive platinum-based chemoradiotherapy. To this end, we performed targeted DNA sequencing on frozen pre-treatment tumor biopsy material from 77 patients with advanced stage oro- and hypopharyngeal carcinoma. This provided somatic point mutation and copy number aberration data of 556 genes. The most frequently mutated genes, TP53 (62%), CCND1 (51%), CDKN2A (30%) and PIK3CA (21%), were not associated with PFS. However, co-occurring CCND1 and CDKN2A mutations were associated with short PFS (HR 2.24, p = 0.028) in HPV-negative tumors. Furthermore, tumor mutational burden (sum of somatic point mutations) showed a trend towards decreased PFS (HR 1.9, p = 0.089), and chromosomal instability (CIN) was associated with shorter PFS (HR 2.3, p = 0.023), independent of HPV status. Our results show that tumor mutational burden, CIN markers, and co-occurring CCND1 and CDKN2A mutations are associated with chemoradiotherapy outcomes in advanced stage oro- and hypopharyngeal HNSCC patients, thereby highlighting their prognostic potential. Given their poor prognosis association and link to biological targets, they may also identify patients for novel targeted therapies and immunotherapies.

Novel genetic alterations and their impact on target therapy response in head and neck squamous cell carcinoma

Head and neck squamous cell carcinoma (HNSCC) is highly variable by tumor site, histologic type, molecular characteristics, and clinical outcome. During recent years, emerging targeted therapies have been focused on driver genes. HNSCC involves several genetic alterations, such as co-occurrence, multiple feedback loops, and cross-talk communications. These different kinds of genetic alterations interact with each other and mediate targeted therapy response. In the current review, it is emphasized that future treatment strategy in HNSCC will not solely be based on "synthetic lethality" approaches directed against overactivated genes. More importantly, biologic, genetic, and epigenetic alterations of HNSCC will be taken into consideration to guide the therapy. The emerging genetic alterations in HNSCC and its effect on targeted therapy response are discussed in detail. Hopefully, novel combination regimens for the treatment of HNSCC can be developed.

Mutation allele frequency threshold does not affect prognostic analysis using next-generation sequencing in oral squamous cell carcinoma

Background

With the development of sequencing technologies, there may be some disputes on sequencing analysis. The aim of this study was to investigate different allele frequency thresholds of mutations in targeted genes on prognostic analyses using a panel of cancer associated gene exons (CAGE) in oral squamous cell carcinoma (OSCC).

Methods

Forty-six patients were included in this study. Twelve genes were sequenced and analyzed using next-generation sequencing from formalin-fixed paraffin-embedded tissues. Allele frequency thresholds of 10, 5, and 3% were used for prognostic analyses.

Results

With a mean sequence depth of 3199-fold, 99% of CAGE were represented by at least 10 reads. Ninety-four non-synonymous (missense [70.2%], nonsense [11.7%], splice site [10.6%], and insertion/deletion [7.5%]) mutations were detected in 40 OSCC patients with an allele frequency threshold of 10%. TP53 (78.3%), NOTCH1 (30.4%), CASP8 (13.0%), CDKN2A (10.9%), and CDH1 (6.5%) were the most frequently mutated genes. Using allele frequency thresholds of 10, 5, and 3%, there were no significant differences in clinical outcomes between patients with non-synonymous mutations and wild type genotypes.

Conclusions

TP53, NOTCH1, CASP8, CDKN2A, and CDH1 are the most frequently mutated genes in OSCC patients. The allele frequency threshold used in this study does not affect the results of clinical outcome analysis.

Electronic supplementary material

The online version of this article (10.1186/s12885-018-4481-8) contains supplementary material, which is available to authorized users.

The NOTCH Pathway in Head and Neck Squamous Cell Carcinoma

Comprehensive genomic analyses have been performed for head and neck squamous cell carcinoma (HNSCC), revealing a significant rate of NOTCH1 mutations and identifying NOTCH1 as the second most frequently mutated gene after TP53. Most NOTCH1 mutations are considered inactivating, indicating that NOTCH1 is a tumor suppressor gene. On the other hand, cohorts from Asian populations with HNSCC have shown activating NOTCH1 mutations. HNSCC with NOTCH1 mutations have a worse prognosis than the NOTCH1 wild-type tumors. Additional data on other NOTCH family members have shown that NOTCH promotes HNSCC progression. NOTCH family members, including NOTCH pathway genes, are upregulated in HNSCC compared with normal tissues, and inhibition of the NOTCH pathway decreases cell proliferation and invasion. NOTCH activity in HNSCC is therefore contextual, and NOTCH in HNSCC is considered to have a bimodal role as a tumor suppressor and an oncogene. In this review, recent understandings of NOTCH pathway genes, including NOTCH genes, in HNSCC are described. In addition, the implications of NOTCH pathway alteration for HNSCC-specific NOTCH-targeted cancer therapy are explored.

FBXW7 expression affects the response to chemoradiotherapy and overall survival among patients with oral squamous cell carcinoma: A single-center retrospective study

FBXW7 (F-box and WD repeat domain containing-7) is a tumor suppressor protein that regulates the degradation of various oncoproteins in several malignancies. However, limited information is available regarding FBXW7 expression in oral squamous cell carcinoma. Therefore, this study aimed to determine the clinical significance of FBXW7 expression in oral squamous cell carcinoma. The FBXW7 expression patterns in oral squamous cell carcinoma and adjacent normal tissues from 15 patients who underwent radical resection were evaluated using quantitative real-time polymerase chain reaction and immunohistochemical staining. In addition, immunohistochemistry was performed using paraffin-embedded sections from biopsy specimens obtained from 110 patients with oral squamous cell carcinoma who underwent surgery after 5 fluorouracil-based chemoradiotherapy. The associations of FBXW7 expression with various clinicopathological features and prognosis were evaluated in these patients. As a results, in the 15 matched samples, the FBXW7 expression was significantly decreased in the oral squamous cell carcinoma tissues compared to that in the adjacent normal tissues. In the clinicopathological analysis, compared to high protein expression, low FBXW7 expression was found to significantly associate with a poor histological response to preoperative chemoradiotherapy. Kaplan-Meier curve analysis revealed that low FBXW7 expression was significantly associated with a poor prognosis, and FBXW7 expression was found to be an independent predictor of overall survival in the multivariate analysis. Our results suggest that FBXW7 may function as a tumor suppressor protein in oral squamous cell carcinoma. In addition, FBXW7 could be a potential biomarker for predicting not only the clinical response to chemoradiotherapy but also overall survival in patients with oral squamous cell carcinoma.

Prevalence of EGFR Tyrosine Kinase Domain Mutations in Head and Neck Squamous Cell Carcinoma: Cohort Study and Systematic Review

BACKGROUND

Mutations in the epidermal growth factor receptor (EGFR) tyrosine kinase domain (TKD) are associated with response and resistance to targeted therapy. The EGFR mutation status in patients with advanced oral and oropharyngeal squamous cell carcinoma (OOSCC) was evaluated. A systematic literature review was undertaken to summarize current evidence and estimate the overall prevalence of EGFR TKD mutations in patients with head and neck squamous cell carcinoma (HNSCC).

MATERIALS AND METHODS

Genomic DNA was extracted from formalin-fixed, paraffin-embedded tumor samples of 113 patients with OOSCC. Pyrosequencing was performed to investigate mutations in EGFR exons 18 to 21. Medline databases were searched for relevant studies. Studies reporting mutations in the EGFR TKD in HNSCC were eligible for inclusion in the systematic review.

RESULTS

No mutations in the EGFR TKD were observed in 113 samples of OOSCC. A total of 53 eligible studies were included in the systematic review. In total, from the review, 117 patients harboring a total of 159 EGFR TKD mutations were reported among 4122 patients with HNSCC. The overall prevalence of EGFR TKD mutations in HNSCC was 2.8%.

CONCLUSION

Large-scale studies are warranted to provide further evidence regarding the mutation status of EGFR in patients with HNSCC.