High ERCC1 expression predicts cisplatin-based chemotherapy resistance and poor outcome in unresectable squamous cell carcinoma of head and neck in a betel-chewing area

Targeting ferroptosis as a potential strategy to overcome the resistance of cisplatin in oral squamous cell carcinoma

Oral squamous cell carcinoma (OSCC) is a crucial public health problem, accounting for approximately 2% of all cancers globally and 90% of oral malignancies over the world. Unfortunately, despite the achievements in surgery, radiotherapy, and chemotherapy techniques over the past decades, OSCC patients still low 5-year survival rate. Cisplatin, a platinum-containing drug, serves as one of the first-line chemotherapeutic agents of OSCC. However, the resistance to cisplatin significantly limits the clinical practice and is a crucial factor in tumor recurrence and metastasis after conventional treatments. Ferroptosis is an iron-based form of cell death, which is initiated by the intracellular accumulation of lipid peroxidation and reactive oxygen species (ROS). Interestingly, cisplatin-resistant OSCC cells exhibit lower level of ROS and lipid peroxidation compared to sensitive cells. The reduced ferroptosis in cisplatin resistance cells indicates the potential relationship between cisplatin resistance and ferroptosis, which is proved by recent studies showing that in colorectal cancer cells. However, the modulation pathway of ferroptosis reversing cisplatin resistance in OSCC cells still remains unclear. This article aims to concisely summarize the molecular mechanisms and evaluate the relationship between ferroptosis and cisplatin resistance OSCC cells, thereby providing novel strategies for overcoming cisplatin resistance and developing new therapeutic approaches.

Oropharyngeal Carcinoma with a Special Focus on HPV-Related Squamous Cell Carcinoma

Human papillomavirus-positive oropharyngeal squamous cell carcinoma (HPV-OPSCC) has one of the most rapidly increasing incidences of any cancer in high-income countries. The most recent (8th) edition of the Union for International Cancer Control/American Joint Committee on Cancer staging system separates HPV-OPSCC from its HPV-negative counterpart to account for the improved prognosis seen in the former. Indeed, owing to its improved prognosis and greater prevalence in younger individuals, numerous ongoing trials are examining the potential for treatment deintensification as a means to improve quality of life while maintaining acceptable survival outcomes. Owing to the distinct biology of HPV-OPSCCs, targeted therapies and immunotherapies have become an area of particular interest. Importantly, OPSCC is often detected at an advanced stage, highlighting the need for diagnostic biomarkers to aid in earlier detection. In this review, we highlight important advances in the epidemiology, pathology, diagnosis, and clinical management of HPV-OPSCC and underscore the need for a progressive understanding of the molecular basis of this disease toward early detection and precision care.

HMG20A was identified as a key enhancer driver associated with DNA damage repair in oral squamous cell carcinomas

Background

Oral squamous cell carcinoma (OSCC) is the main type of oral cancer. Disturbing DNA repair is an invaluable way to improve the effectiveness of tumor treatment. Here, we aimed to explore the key enhancer drivers associated with DNA damage repair in OSCC cells.

Methods

Gene Set Enrichment Analysis (GSEA), Gene Set Variation Analysis (GSVA) and Kaplan-Meier analysis were applied to explore the relationship among DNA repair-related genes expression and clinical phenotypes based on The Cancer Genome Atlas (TCGA) database. HOMER software and Integrative Genomics Viewer were applied to identify and visualize enhancers using GSE120634. Toolkit for Cistrome Data Browser was applied to predict transcription factors. Human Protein Atlas Database was used to analyze the protein levels of transcription factors in OSCC and control tissues. Seventy-two OSCC patients were included in this study. qRT-PCR was used to detect transcription factor expression in OSCC and adjacent control tissues collected in this study. qRT-PCR and ChIP-qPCR were used to verify the binding of transcription factors to enhancers, and regulation of target genes transcription. Transcription factor knockdown and control cells were treated with cisplatin. CCK8 was used to detect cell viability and proliferation. Western blotting was implemented to detect the levels of DNA repair-related proteins. Transwell assay was used to detect cell invasion.

Results

DNA repair was positively associated with the OSCC metastatic phenotype. Patients in the cluster with high expression of DNA repair-related genes had a worse prognosis and a higher proportion of advanced stage, low-differentiation, alcohol consumption and smoking compared to the cluster with low DNA repair-related gene expression. Seventeen metastasis-specific enhancer-controlled upregulated DNA repair-related genes, with the top two upregulated genes being ADRM1 26 S proteasome ubiquitin receptor (ADRM1) and solute carrier family 12 member 7 (SLC12A7) were screened. High mobility group 20 A (HMG20A) was the key prognostic enhancer driver regulating metastasis-specific DNA repair-related genes, with higher expression in OSCC tissues than normal control tissues, and higher expression in metastatic OSCC tissues than non-metastatic OSCC tissues. HMG20A bound to the metastasis-specific enhancers of ADRM1 and SLC12A7, thereby promoting ADRM1 and SLC12A7 expression. Knockdown of HMG20A enhanced cisplatin sensitivity of cells, and inhibited OSCC cells from repairing DNA damage caused by cisplatin, as well as proliferation and invasion of OSCC cells.

Conclusion

HMG20A was identified as the key prognostic enhancer driver regulating DNA repair in OSCC cells, providing a new therapeutic target for OSCC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02500-y.

Mechanisms of Cisplatin Resistance in HPV Negative Head and Neck Squamous Cell Carcinomas

Head and neck squamous cell carcinomas (HNSCCs) are the eighth most common cancers worldwide. While promising new therapies are emerging, cisplatin-based chemotherapy remains the gold standard for advanced HNSCCs, although most of the patients relapse due to the development of resistance. This review aims to condense the different mechanisms involved in the development of cisplatin resistance in HNSCCs and highlight future perspectives intended to overcome its related complications. Classical resistance mechanisms include drug import and export, DNA repair and oxidative stress control. Emerging research identified the prevalence of these mechanisms in populations of cancer stem cells (CSC), which are the cells mainly contributing to cisplatin resistance. The use of old and new CSC markers has enabled the identification of the characteristics within HNSCC CSCs predisposing them to treatment resistance, such as cell quiescence, increased self-renewal capacity, low reactive oxygen species levels or the acquisition of epithelial to mesenchymal transcriptional programs. In the present review, we will discuss how cell intrinsic and extrinsic cues alter the phenotype of CSCs and how they influence resistance to cisplatin treatment. In addition, we will assess how the stromal composition and the tumor microenvironment affect drug resistance and the acquisition of CSCs' characteristics through a complex interplay between extracellular matrix content as well as immune and non-immune cell characteristics. Finally, we will describe how alterations in epigenetic modifiers or other signaling pathways can alter tumor behavior and cell plasticity to induce chemotherapy resistance. The data generated in recent years open up a wide range of promising strategies to optimize cisplatin therapy, with the potential to personalize HNSCC patient treatment strategies.

The Molecular Basis and Therapeutic Aspects of Cisplatin Resistance in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) is a kind of malignant tumors with low survival rate and prone to have early metastasis and recurrence. Cisplatin is an alkylating agent which induces DNA damage through the formation of cisplatin-DNA adducts, leading to cell cycle arrest and apoptosis. In the management of advanced OSCC, cisplatin-based chemotherapy or chemoradiotherapy has been considered as the first-line treatment. Unfortunately, only a portion of OSCC patients can benefit from cisplatin treatment, both inherent resistance and acquired resistance greatly limit the efficacy of cisplatin and even cause treatment failure. Herein, this review outline the underlying mechanisms of cisplatin resistance in OSCC from the aspects of DNA damage and repair, epigenetic regulation, transport processes, programmed cell death and tumor microenvironment. In addition, this review summarizes the strategies applicable to overcome cisplatin resistance, which can provide new ideas to improve the clinical therapeutic outcome of OSCC.

Drug resistance against 5-fluorouracil and cisplatin in the treatment of head and neck squamous cell carcinoma: A systematic review

Head and neck cancers are highly prevalent worldwide. Most of these lesions are diagnosed in the advanced stages of the disease. Thus, they do not often have a good long-term prognosis. Like other cancer types, head and neck cancers are managed by surgery, radiotherapy, and chemotherapy. Despite significant advances in the treatment of oral squamous cell carcinoma (OSCC), physicians encounter several challenges in the course of treatment. Various mechanisms mediate the clinical responses of a certain cancer to medications. Thus, efficient treatment planning requires adequate knowledge about the genes involved in drug resistance and the evaluation of the frequency percentage of resistance. Several studies have evaluated the causes and frequency percentages of 5-fluorouracil (5-FU) and cisplatin resistance. In this systematic review, all the relevant articles published until November 30, 2019, were retrieved from the Scopus, Embase, Medline, ISI, Web of Science, and Cochrane databases using certain MeSH and EMTTree keywords. A total of 2164 articles were retrieved of which, 18 were included in the review since they had reported the frequency percentages of drug resistance. Of all, 10 articles had evaluated cisplatin (1317 samples). A meta-analysis of the results revealed a frequency of 33% for cisplatin resistance. Eight studies had evaluated 5-FU (476 samples). A meta-analysis of the results revealed a frequency of 40.2 % for 5-FU resistance. Overcoming cisplatin resistance or 5-FU resistance can significantly enhance recovery in advanced HNSCC. Attempts should be made to eliminate the cause and use multi-drug regimens to increase the success rate of treatment.

HPV Positive Status Is a Favorable Prognostic Factor in Non-Nasopharyngeal Head and Neck Squamous Cell Carcinoma Patients: A Retrospective Study From the Surveillance, Epidemiology, and End Results Database

Objective

To investigate the impact of the human papillomavirus (HPV) status on head and neck squamous cell carcinoma (HNSCC) arising from different anatomic subsites.

Methods

HNSCC patients with known HPV status from the Surveillance, Epidemiology, and End Results (SEER) database between 2010–2015 were included in our analysis. Patients were classified into three categories of HNSCC according to Site recode ICD-O-3/WHO 2008 and Primary Site-labeled, namely, oropharynx, hypopharynx, and nasopharynx. Logistic regression model was conducted to evaluate the relationship between patient characteristics and HPV status. Kaplan-Meier methods and COX regression analysis were used to analyze survival data.

Results

A total of 9,943 HNSCC patients with known HPV status from the SEER database were enrolled, with 6,829 (68.7%) HPV-positive patients. HPV-positive and HPV-negative HNSCC were distinct and had different clinical and socioeconomic features (all P < 0.001). Primary sites, socioeconomical factors (age, sex, marital status, and race), and pathological features (TNM stage and grade) were closely related with HPV status (all P < 0.001). HPV-positive status was a favorable prognostic marker in HNSCC patients with cancers of the oropharynx and hypopharynx (all P < 0.001), but was not in nasopharyngeal carcinoma patients (P = 0.843). A total of 8,933 oropharyngeal carcinoma (OPC) and 558 hypopharyngeal carcinoma (HPC) patients were divided into the training and validation cohorts with a ratio of 1:1. Significant prognostic factors of the OS yielded by multivariate COX analysis in the training cohort were integrated to construct nomograms for OPC and HPC patients. The prognostic models showed a good discrimination with a C-index of 0.79 ± 0.007 and 0.73 ± 0.023 in OPC and HPC, respectively. Favorable calibration was reflected by the calibration curves. Additionally, corresponding risk classification systems for OPC and HPC patients based on the nomograms were built and could perfectly classify patients into low-risk, intermediated-risk, high-risk groups. OS in the three risk groups was accurately differentiated and showed a good discrimination.

Conclusion

HPV positivity was associated with an improved survival in HNSCC patients with cancers of the oropharynx and hypopharynx. Nomograms and corresponding risk classification systems were constructed to assist clinicians in evaluating the survival of OPC and HPC patients.

Targeting DNA Damage Response and Repair to Enhance Therapeutic Index in Cisplatin-Based Cancer Treatment

Platinum-based chemotherapies, such as cisplatin, play a large role in cancer treatment. The development of resistance and treatment toxicity creates substantial barriers to disease control, yet. To enhance the therapeutic index of cisplatin-based chemotherapy, it is imperative to circumvent resistance and toxicity while optimizing tumor sensitization. One of the primary mechanisms by which cancer cells develop resistance to cisplatin is through upregulation of DNA repair pathways. In this review, we discuss the DNA damage response in the context of cisplatin-induced DNA damage. We describe the proteins involved in the pathways and their roles in resistance development. Common biomarkers for cisplatin resistance and their utilization to improve patient risk stratification and treatment personalization are addressed. Finally, we discuss some of the current treatments and future strategies to circumvent the development of cisplatin resistance.

Molecular Mechanisms of Chemotherapy Resistance in Head and Neck Cancers

Chemotherapy resistance is a huge barrier for head and neck cancer (HNC) patients and therefore requires close attention to understand its underlay mechanisms for effective strategies. In this review, we first summarize the molecular mechanisms of chemotherapy resistance that occur during the treatment with cisplatin, 5-fluorouracil, and docetaxel/paclitaxel, including DNA/RNA damage repair, drug efflux, apoptosis inhibition, and epidermal growth factor receptor/focal adhesion kinase/nuclear factor-κB activation. Next, we describe the potential approaches to combining conventional therapies with previous cancer treatments such as immunotherapy, which may improve the treatment outcomes and prolong the survival of HNC patients. Overall, by parsing the reported molecular mechanisms of chemotherapy resistance within HNC patient’s tumors, we can improve the prediction of chemotherapeutic responsiveness, and reveal new therapeutic targets for the future.

Excision repair cross-complementing group 2 upregulation is a potential predictive biomarker for oral squamous cell carcinoma recurrence

Oral cancer is the fourth most common type of cancer among males in Taiwan, and the prognosis for patients with advanced-stage oral squamous cell carcinoma (OSCC) remains poor. The present study investigated the prognostic value of three DNA repair genes, namely excision repair cross-complementing group 1 (ERCC1), ERCC2 and X-ray repair cross-complementing group 1 (XRCC1) in OSCC. The protein expression levels of XRCC1, ERCC1 and ERCC2 in oral cell lines were analyzed via western blotting and immunohistochemistry using samples from 98 patients with biopsy-proven OSCC, while the χ² test was used to analyze the clinicopathological association. Kaplan-Meier estimates were used to determine the prognostic value of XRCC1, ERCC1 and ERCC2 for overall survival, and the log-rank test was used to evaluate the significance of differences. Multivariate analysis revealed a positive association between ERCC2 expression and OSCC recurrence (19.64-fold; 95% CI, 5.00-77.1; P<0.001). In addition, the high protein expression levels of XRCC1, ERCC1 and ERCC2 were associated with poor disease-free and overall survival rates. Therefore, the present study suggested that high ERCC2 expression may be a risk factor for OSCC recurrence.

A Combined Systemic Strategy for Overcoming Cisplatin Resistance in Head and Neck Cancer: From Target Identification to Drug Discovery

Simple Summary

The efficiency of cisplatin is limited by drug resistance in head–neck cancer (HNC) patients. In this study, we established a cisplatin resistance (CR) cell model, generated CR related transcriptome profiling, and combined application of bioinformatics methodology to discover a possible way to overcome CR. Analysis of the functional pathway revealed that mitotic division is a novel mechanism significantly contributing to CR. Spindle pole body component 25 (SPC25), a kinetochore protein, was overexpressed in CR cells and significantly correlated with worse HNC patient survival. The silencing of SPC25 increased cisplatin sensitivity and reduced cancer stemness property. Integration of CR transcriptome profiling and drug database discovered a natural extract compound, celastrol, possessing a potent cytotoxic effect in CR cells to reverse CR. Thus, we combined systemic strategies to demonstrated that a novel biological process (mitotic cell division), a hub gene (SPC25), and a natural compound (celastrol) as novel strategies for the treatment of refractory HNC.

Abstract

Cisplatin is the first-line chemotherapy agent for head and neck cancer (HNC), but its therapeutic effects are hampered by its resistance. In this study, we employed systemic strategies to overcome cisplatin resistance (CR) in HNC. CR cells derived from isogenic HNC cell lines were generated. The CR related hub genes, functional mechanisms, and the sensitizing candidates were globally investigated by transcriptomic and bioinformatic analyses. Clinically, the prognostic significance was assessed by the Kaplan–Meier method. Cellular and molecular techniques, including cell viability assay, tumorsphere formation assay, RT-qPCR, and immunoblot, were used. Results showed that these CR cells possessed highly invasive and stem-like properties. A total of 647 molecules was identified, and the mitotic division exhibited a novel functional mechanism significantly related to CR. A panel of signature molecules, MSRB3, RHEB, ULBP1, and spindle pole body component 25 (SPC25), was found to correlate with poor prognosis in HNC patients. SPC25 was further shown as a prominent molecule, which markedly suppressed cancer stemness and attenuated CR after silencing. Celastrol, a nature extract compound, was demonstrated to effectively inhibit SPC25 expression and reverse CR phenotype. In conclusion, the development of SPC25 inhibitors, such as the application of celastrol, maybe a novel strategy to sensitize cisplatin for the treatment of refractory HNC.

Expression and Genetic Polymorphisms of ERCC1 in Chinese Han Patients with Oral Squamous Cell Carcinoma

The aim of this study was to investigate the expression of the excision repair cross-complementation group 1 (ERCC1) in oral squamous cell carcinoma (OSCC) and the possible association of ERCC1 polymorphisms with susceptibility and response to chemotherapy of OSCC in a Chinese Han population. The expression of ERCC1 was determined by real-time PCR in eight patients. Four single-nucleotide polymorphisms (SNPs) rs11615, rs3212948, rs3212961, and rs735482 of ERCC1 were genotyped in 113 OSCC patients and 184 healthy controls using a PCR restriction matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) assay. We found that a higher gene expression of ERCC1 was observed in tumor tissue as compared to pericarcinomatous tissue in OSCC patients. All genotypic and allelic frequencies of the tested ERCC1 polymorphisms were in Hardy-Weinberg equilibrium. The genotypic and allelic frequencies of rs11615, rs3212948, rs3212961, and rs735482 of ERCC1 were not different between OSCC patients and controls. No correlation was observed between ERCC1 polymorphisms and the response to chemotherapy. Our results show that ERCC1 is increased in the tumor tissue of OSCC patients. The investigated ERCC1 gene polymorphisms (rs11615, rs3212948, rs3212961, and rs735482) are not associated with the susceptibility and response to chemotherapy of OSCC in our investigated Chinese Han population.

Elucidating the role of excision repair cross-complement group 1 in oral epithelial dysplasia and early invasive squamous cell carcinoma: An immunohistochemical study

Objectives:

Oral epithelial dysplasia (OED) is characterized by cellular alterations which have the proclivity of progressing to squamous cell carcinoma. Excision repair cross-complement group 1 (ERCC1) is one of the key proteins involved in nucleotide excision repair (NER) pathway. The expression of ERCC1 has been studied in colorectal, esophageal, ovarian and oral squamous cell carcinoma; but, very few studies have been done to apprehend the expression of ERCC1 in OED and early invasive squamous cell carcinoma (EISCC). The goal of this study is to evaluate the role of ERCC1 in OED and EISCC.

Materials and Methods:

Histopathologically diagnosed cases of moderate dysplasia (n = 10), severe dysplasia (n = 10) and EISCC (n = 10) were retrieved. 4 μ thick sections were cut from the formalin-fixed paraffin-embedded tissue blocks. The sections were immunohistochemically stained for ERCC1 following standard protocols. The expression of ERCC1 was evaluated semiquantitatively. Statistical analysis was carried out using Fischer's exact t-test.

Results:

The expression of ERCC1 was found to be strong (+3) in EISCC, moderate (+2) in severe dysplasia and mild (+1) in moderate dysplasia. Thus, the results were statistically significant between the three groups (P < 0.001).

Conclusion:

Disruption in the mechanisms that regulate cell cycle checkpoints and DNA repair mechanism results in genomic instability; these alterations might contribute to carcinoma. ERCC1 is essential to repair the DNA damage induced by various carcinogens. The present study shows significant difference in the expression of ERCC1 between EISCC and OED, which suggests ERCC1 could be used as one of the predictive markers.

Multifaceted Mechanisms of Areca Nuts in Oral Carcinogenesis: the Molecular Pathology from Precancerous Condition to Malignant Transformation

Oral cancer is one of the most frequent malignant diseases worldwide, and areca nut is a primary carcinogen causing this cancer in Southeast Asia. It has been widely reported that areca nut induced several cytotoxic effects in oral cells, including ROS generation, inflammation, tissue hypoxia, DNA damage, and cell invasion. Recently, through chronic exposure model, more extensive pathological effects due to areca nut have been found. These include the induction of autophagy, promotion of epithelial- mesenchymal transition, and facilitation of cancer stemness conversion. Clinical findings support these adverse effects. Oral submucosal fibrosis, a premalignant condition, is prevalent in the area with habitual chewing of areca nuts. Consistently, oral cancer patients with habitual chewing areca nut exhibit more aggressive phenotypes, including resistance to chemo-radiotherapy. In this review, we comprehensively discuss and concisely summarize the up-to-date molecular and cellular mechanisms by which areca nuts contribute to malignant transformation. This review may provide critical information regarding clinical applications in risk assessment, disease prevention, diagnosis, and personalized therapeutics for areca nut-induced oral malignancy.

Adaptive Responses to Monotherapy in Head and Neck Cancer: Interventions for Rationale-Based Therapeutic Combinations

Most Phase II and III clinical trials in head and neck cancer (HNC) combine two or more treatment modalities, which are based, in part, on knowledge of the molecular mechanisms of innate and acquired resistance to monotherapy. In this review, we describe the range of tumor-cell autonomously derived (intrinsic) and tumor-microenvironment-derived (extrinsic) acquired-resistance mechanisms to various FDA-approved monotherapies for HNC. Specifically, we describe how tumor cells and the tumor microenvironment (TME) respond to radiation, chemotherapy, targeted therapy (cetuximab), and immunotherapies [programmed cell death 1 (PD-1) inhibitors] and adapt to the selective pressure of these monotherapies. Due to the diversity of adaptive responses to monotherapy, monitoring the response to treatment in patients is critical to understand the path that leads to resistance and to guide the optimal therapeutic drug combinations in the clinical setting. We envisage that applying such a rationale-based therapeutic strategy will improve treatment efficacy in HNC patients.

Association Study Among Candidate Genetic Polymorphisms and Chemotherapy-Related Severe Toxicity in Testicular Cancer Patients

Testicular cancer is one of the most commonly occurring malignant tumors in young men with fourfold higher rate of incidence and threefold higher mortality rates in Chile than the average global rates. Surgery is the initial line of treatment for testicular cancers, and is generally followed by chemotherapy, usually with combinations of bleomycin, etoposide, and cisplatin (BEP). However, the adverse effects of chemotherapy vary significantly among individuals; therefore, the present study explored the association of functionally significant allelic variations in genes related to the pharmacokinetics/pharmacodynamics of BEP and DNA repair enzymes with chemotherapy-induced toxicity in BEP-treated testicular cancer patients. We prospectively recruited 119 patients diagnosed with testicular cancer from 2010 to 2017. Genetic polymorphisms were analyzed using PCR and/or qPCR with TaqMan^®probes. Toxicity was evaluated based on the Common Terminology Criteria for Adverse Events, v4.03. After univariate analyses to define more relevant genetic variants (p < 0.2) and clinical conditions in relation to severe (III–IV) adverse drug reactions (ADRs), stepwise forward multivariate logistic regression analyses were performed. As expected, the main severe ADRs associated with the non-genetic variables were hematological (neutropenia and leukopenia). Univariate statistical analyses revealed that patients with ERCC2 rs13181 T/G and/or CYP3A4 rs2740574 A/G genotypes are more likely to develop alopecia; patients with ERCC2 rs238406 C/C genotype may develop leukopenia, and patients with GSTT1-null genotype could develop lymphocytopenia (III–IV). Patients with ERCC2 rs1799793 A/A were at risk of developing severe anemia. The BLMH rs1050565 G/G genotype was found to be associated with pain, and the GSTP1 G/G genotype was linked infection (p < 0.05). Multivariate analysis showed an association between specific ERCC1/2 genotypes and cumulative dose of BEP drugs with the appearance of severe leukopenia and/or febrile neutropenia. Grades III–IV vomiting, nausea, and alopecia could be partly explained by the presence of specific ERCC1/2, MDR1, GSTP1, and BLMH genotypes (p < 0.05). Hence, we provide evidence for the usefulness of pharmacogenetics as a tool for predicting severe ADRs in testicular cancer patients treated with BEP chemotherapy.

Phytochemicals: Current strategy to sensitize cancer cells to cisplatin

Cisplatin-based chemotherapeutic regimens are the most frequently used adjuvant treatments for many types of cancer. However, the development of chemoresistance to cisplatin results in treatment failure. Despite the significant developments in understanding the mechanisms of cisplatin resistance, effective strategies to enhance the chemosensitivity of cisplatin are lacking. Phytochemicals are naturally occurring plant-based compounds that can augment the anti-cancer activity of cisplatin, with minimal side effects. Notably, some novel phytochemicals, such as curcumin, not only increase the efficacy of cisplatin but also decrease toxicity induced by cisplatin. However, the exact mechanisms underlying this process remain unclear. In this review, we discussed the progress made in utilizing phytochemicals to enhance the anti-cancer efficacy of cisplatin. We also presented some ideal phytochemicals as novel agents for counteracting cisplatin-induced organ damage.

ERCC1, XPF and XPA-locoregional differences and prognostic value of DNA repair protein expression in patients with head and neck squamous cell carcinoma

OBJECTIVES

Nucleotide excision repair protein expression has been claimed to be responsible for platinum-based chemotherapy resistance. ERCC1, XPF and XPA, core proteins in DNA repair, were evaluated regarding their prognostic value in patients with head and neck squamous cell carcinoma by looking at overall survival and time to recurrence.

MATERIALS AND METHODS

Tissue microarrays were constructed from 453 cases of HNSCC, including 222 oral (49%), 126 oropharyngeal (27.8%) and 105 laryngeal (23.2%) tumours. There were 284 XPF, 293 XPA and 294 ERCC1 specimens evaluable for protein expression analysis after immunohistochemical workup. Expression levels were dichotomised into high- and low-expressing groups. Outcomes for overall survival (OS) and time to recurrence (TTR) were analysed using the Kaplan-Meier method.

RESULTS

No correlation between ERCC1, XPA and XPF expression and OS was found by looking at the overall patient cohort. However, subsite analysis revealed that high ERCC1 expression was associated with a significantly inferior OS in patients with SCC of the oral cavity (p = 0.028) and showed an independent predictive value in multivariate analysis (p = 0.0123). High XPA expression showed a significantly increased OS in patients with oropharyngeal SCC (p = 0.0386). Regarding XPF, no impact on OS in any subsite could be shown.

CONCLUSIONS

While high ERCC1 expression functions as a predictive marker with decreased OS in patients with squamous cell carcinoma of the oral cavity, high XPA expression shows an inverse effect in the subsite of the oropharynx, which has not been described previously.

CLINICAL RELEVANCE

ERCC1 and XPA might be candidates to overcome chemotherapy resistance in subtypes of HNSCC.

Cytokine-Induced Killer Cells Modulates Resistance to Cisplatin in the A549/DDP Cell Line

Background Cytokine-induced killer (CIK) cells can potentially enhance the tumor-killing activity of chemotherapy. Objective This study aimed to evaluate the effects of CIK cells on cisplatin (DDP) resistance in the human lung adenocarcinoma cell line A549/DDP. Methods The detect resistance index, drug resistance related-genes and cytokine secretion of A549/DDP co-cultured with CIK cells were assayed in vitro. ResultsAfter A549/DDP co-culture with CIK cells, the DDP resistance of A549/DDP significantly decreased in a time-dependent manner. The DDP resistance of A549/DDP co-cultured with CIK cells for 20 h decreased 4.93-fold compared with that of A549/DDP cells cultured alone (P<0.05). The mRNA and protein expression levels of the glutathione-S-transferase (GST) -π gene in A549/DDP significantly decreased after co-culture with CIK cells (P<0.05). The secretion of interferon (IFN)- γ significantly increased along with the co-culture time of A549/DDP with CIK cells. The expression of GST-π was restored by adding the neutralizing IFN-γ. ConclusionCIK cells can reverse the drug resistance of A549/DDP in a time-dependent manner by reducing GST-π expression to increase the accumulation of DDP. The effect of CIK cells on re-sensitizing lung cancer cells to the chemotherapy drug was partially dependent on the secretion of IFN-γ.

Prognostic implication of ERCC1 protein expression in resected oropharynx and oral cavity cancer

BACKGROUND

Excision repair cross complement group 1 (ERCC1) expression is a predictive biomarker for platinum-containing treatment in squamous cell carcinoma of head and neck (SCCHN). However, the prognostic significance after surgical resection is not well understood.

METHODS

Oropharynx (n=143) or oral cavity (n=61) SCCHN patients undergoing surgery were included. ERCC1 protein expression and HPV status were assessed by ERCC1 and p16 immunohistochemistry.

RESULTS

The ERCC1, over-expressed in 66.7% of patients, was associated with oral cavity cancer (P<0.001), well differentiation (P=0.036), and HPV negativity (P<0.001). In TCGA database, ERCC1 mRNA upregulation was enriched in HPV-negative and oral cavity cancers, and associated with HRAS mutation (P<0.001). The prognostic role of ERCC1 was not different according to HPV status. High ERCC1 expression showed a trend toward poor prognosis in patients with an advanced stage (P=0.079) with marginal significance.

CONCLUSIONS

The ERCC1 expression was not prognostic in surgically resected oropharynx/oral cavity SCCHN, irrespective of HPV status. However, it could provide additional prognostic information for advanced stage patients.

Comparative molecular profiling of HPV-induced squamous cell carcinomas

Approximately 5% of all cancer incidences result from human papillomavirus (HPV) infection. HPV infection most commonly leads to cancers of the anogenital region or oropharynx. It is unknown whether different HPV-mediated cancers collectively share a molecular signature and it is important to determine if there are targetable alterations common to different types of HPV-positive tumors. We analyzed 743 p53 wild-type samples of anal, cervical, oropharyngeal, and vulvar squamous cell carcinomas which underwent multiplatform testing at a commercial molecular profiling service. Expression of 24 proteins was measured by immunohistochemistry (IHC), mutation of 48 genes was determined by next-generation and Sanger sequencing, and copy number alteration for six genes was determined by in situ hybridization. The four cohorts had remarkably similar molecular profiles. No gene had a statistically significant difference in mutation frequency or copy number change between the four different types of squamous cell carcinomas. The only significant differences between cohorts were frequency of ERCC1 and SPARC loss as determined by IHC. In all four cancer types, oncogene mutation and PD-L1 expression was relatively infrequent. The most commonly mutated gene was PIK3CA, with mutations most often affecting the helical domain of the protein and accompanied by concurrent lack of PTEN expression. Loss of MGMT and RRM1 was common among the four cohorts and may be predictive of response to cytotoxic therapies not currently being used to treat these cancer types. The similar molecular profiles of the four cohorts indicate that treatment strategies may be similarly efficacious across HPV-positive cancers.

Assessment and Improvement of Quality of Life in Patients Undergoing Treatment for Head and Neck Cancer

Introduction: We compared the pre and post-treatment quality of life in head and neck cancer (HNC) patients and identified factors that could improve the quality of life in such patients.  

Methods: The European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 (EORTC QLQ-C30) questionnaire was administered to 84 patients’ pre and post-treatment. Patients who had non-metastatic, measurable, and untreated HNCs were invited, provided that their age was below 80 years. We did not discriminate based on treatment modality, stage of cancer, or co-morbidities. Patients who were mentally incapacitated, with secondary or recurrent HNC, distant metastasis, skin cancer, congenital anomaly of the head and neck, chronic illness, or any previous or current psychiatric illness were excluded from the study. A high mean score on the functional scale and a low score on symptom scale signify a better quality of life. We used the dependent t-test to compare pre and post-treatment scores.

Results: We found no statistically significant differences in any variables, except the four symptom scales of diarrhoea, constipation, nausea/vomiting, and financial difficulty. All of these variables had increased mean scores with p values of < 0.001. Also, we found no statistical significance (p = 0.250) when comparing the pre-treatment (59.4 ± 18.3) and post-treatment (61.2 ± 16.2) scores for the global health status.

Conclusion: We found no improvement in the quality of life in HNC patients despite intervention. In fact, diarrhoea, constipation, nausea/vomiting, and financial difficulty of these patients worsened post-treatment.

Development and Validation of an ERCC1 Immunohistochemistry Assay for Solid Tumors

CONTEXT

- Excision repair cross-complementation 1 (ERCC1) is a key enzyme in nuclear excision repair pathway and has a critical role in helping remove DNA adducts caused by cross-linking agents, such as platinum-containing cancer chemotherapies and other DNA-damaging therapeutic modalities. ERCC1 expression, evaluated by techniques such as immunohistochemistry, has been associated with clinical response; ERCC1⁺ tumors are more resistant to cisplatin treatment than are ERCC1^- tumors. Although several immunohistochemistry, anti-ERCC1 antibodies are available, the 8F1 clone, in particular, has been used in many studies. Recent evidence has suggested that the 8F1 antibody cross-reacts with at least one other protein, raising concerns about the specificity of this clone.

OBJECTIVE

- To design an immunohistochemistry assay to detect ERCC1 levels that show dynamic range and consistent analytic performance.

DESIGN

- Two different primary antibodies to ERCC1, clones 4F9 and D6G6, were evaluated on formalin-fixed, paraffin-embedded tissue. We then performed a fit-for-purpose assay validation with the 4F9 clone, which included sensitivity assessment across several solid tumor types and evaluation of analytic parameters, such as precision and reproducibility.

RESULTS

- The 4F9 clone was consistently superior to the D6G6 clone in the optimization phase. A range of expression was seen in ovarian, head and neck, non-small cell lung, and esophageal cancer samples when tested with the 4F9 clone. The antibody showed acceptable reproducibility (31.02%) and precision (16.06%).

CONCLUSIONS

- This assay can be used to assess ERCC1 levels during clinical studies of patient tumors from a variety of tumor types.

Clinical observation of gene expression-guided chemoradiation therapy for nonsurgical esophageal squamous cell carcinoma patients: a retrospective analysis of 36 cases

Objective

To make an informed choice of chemotherapy drugs according to the oncogene mRNA expression and to explore whether it could increase the survival rate of patients.

Patients and methods

The study retrospectively analyzed 36 cases of nonsurgical esophageal squamous cell carcinoma patients treated at the Center for Oncology of Shandong Provincial Hospital from December 1, 2010, to November 1, 2013. Intensity-modulated radiation therapy was used for the treatment with a conventional radiotherapy dose of 60–66 Gy. Chemotherapy started 1–5 weeks after radiation therapy. The selection of the chemotherapy drug was based on the mRNA expression levels of excision repair cross-complementation 1, thymidylate synthetase, ribonucleotide reductase M1, and β-tubulin isotype III. The objective response rate, progression-free survival, and overall survival were observed.

Results

The reason for poor prognosis of patients with high expression of excision repair cross-complementation 1 was unknown. No correlation was observed between patient survival and expression of thymidylate synthetase, ribonucleotide reductase M1, and β-tubulin isotype III. Complete response, partial response, stable disease, and progressive disease were observed in 25, five, three, and three patients, respectively. The objective response rate was 83.3%. The 1-year, 2-year, and 3-year progression-free survival rates were 79.8%, 58.9%, and 54.4%, respectively. The 1-year, 2-year, and 3-year overall survival rates were 83.3%, 68.1%, and 58.4%, respectively.

Conclusion

Selecting the chemotherapy drug according to the oncogene expression, combined with radiation therapy, could increase the 3-year survival rate in nonsurgical esophageal squamous cell carcinoma patients. Such conclusion needs to be further confirmed using a larger sample size.

Betel nut chewing history is an independent prognosticator for smoking patients with locally advanced stage IV head and neck squamous cell carcinoma receiving induction chemotherapy with docetaxel, cisplatin, and fluorouracil

Background

Smoking and betel nut chewing are well-known risk factors for head and neck squamous cell carcinoma (HNSCC). Smoking is also a strong prognosticator for patients with locally advanced HNSCC receiving induction chemotherapy. Smoking with or without betel nut chewing is a common practice in Asia. However, little is known regarding whether betel nut chewing can serve as a prognostic factor for smoking patients with locally advanced HNSCC receiving induction chemotherapy. The aim of this study was to evaluate the prognostic impact of betel nut chewing in such patients receiving induction chemotherapy with docetaxel, cisplatin, and fluorouracil (TPF).

Methods

From January 2010 to December 2012, we retrospectively analyzed 162 smoking patients with locally advanced HNSCC who received induction chemotherapy with TPF at our institution. Background characteristics, including a history of betel nut chewing, were analyzed as potential prognostic factors.

Results

Among the 162 smoking patients, 131 patients (81 %) were betel nut chewers, while 31 (19 %) were non-betel nut chewers. One hundred fifty-six (96 %) were men, and 6 (4 %) were women. The median age was 53 years. The overall response rates to induction chemotherapy were 57 and 77 % in patients with and without betel nut chewing history, respectively (P = 0.038). The 2-year progression survival rates were 37 and 67 % in patients with and without betel nut chewing history, respectively (P = 0.004). The 2-year overall survival rates were 47 and 71 % in patients with and without betel nut chewing history, respectively (P = 0.017). Betel nut chewing history was independently associated with a poor response to induction chemotherapy, an inferior progression-free survival rate, and a poor overall survival rate.

Conclusions

Our results indicate that betel nut chewing history is independently associated with poor prognosis in smoking patients with locally advanced HNSCC receiving induction chemotherapy with TPF. Further investigation is warranted to explain this effect of betel nut chewing history on these patients’ prognosis.

The prognostic and predictive value of excision repair cross-complementation group 1 (ERCC1) protein in 1288 patients with head and neck squamous cell carcinoma treated with platinum-based therapy: a meta-analysis

Excision repair cross-complementation group 1 (ERCC1) protein has been extensively investigated as a prognostic and predictive factor for platinum-based treatment in head and neck squamous cell carcinoma (HNSCC) but with inconsistent results. We performed the present meta-analysis to better elucidate this issue in advanced HNSCC. A literature search was conducted using the PubMed and Web of Science databases. The inclusion criteria were head and neck cancer patients with platinum-based treatment and evaluation of the correlation between ERCC1 expression and clinical outcomes [objective response rate (ORR), progression-free survival (PFS), and overall survival (OS), both unadjusted and adjusted estimates]. In high vs. low pooled analyses, high ERCC1 expression was associated with unfavorable OS [hazard ratio (HR) = 1.95, 95 % confidence interval (CI) 1.18-3.21, p = 0.009], PFS (HR = 2.39, 95 % CI 1.74-3.28, p = 0.000) and ORR (odds ratio = 0.48, 95 % CI 0.23-0.98, p = 0.044). In the subgroup analysis of adjusted OS estimates, ERCC1 was a predictor of shorter survival in Asians (HR = 3.13, 95 % CI 2.09-4.70, p = 0.000) and Caucasians (HR = 2.02, 95 % CI 1.32-3.07, p = 0.001) but of longer survival in South Americans (HR = 0.17, 95 % CI 0.07-0.40, p = 0.000). Immunohistochemistry proved to be of predictive value irrespective of used antibody (p = 0.009). In the stratified analysis according to the tumor site, ERCC1 expression was associated with OS in nasopharyngeal cancer (HR = 2.72, 95 % CI 1.79-4.13, p = 0.000). ERCC1 has a potential to become predictive and prognostic factor enabling treatment tailoring in HNSCC patients.

The roles of excision repair cross-complementation group1 in objective response after cisplatin-based concurrent chemoradiotherapy and survival in head and neck cancers: a systematic review and meta-analysis

Our aim of the study was to investigate the precise relationship of repair cross-complementation group 1 (ERCC1) expression and the survival as well as objective response rate to cisplatin-based concurrent chemoradiotherapy (CCRT) and a meta-analysis was conducted to analysis ERCC1's prognostic roles in head and neck cancer. A search based on published articles in PubMed, Embase and CKNI database (up to Oct 15, 2014) to find eligible studies meeting eligibility criteria and then a meta-analysis was conducted to assess the outcomes in head and neck squamous cell carcinomas (HNSCC) patients with different ERCC1 expression. The principle outcomes were hazard ratio (HR) for survival analysis and relative risks (RR) for objective response. Fixed or random model was used for calculation according to the heterogeneity. The results showed that 9 studies involving 568 patients met the inclusion criteria. Low/negative expression of ERCC1 was associated with longer overall survival (OS) and profession-free survival (PFS) after receiving cisplatin-based CCRT therapy (HR 0.38; 95% confidence interval (CI) 0.21-0.63; P<0.001 and HR 0.37; 95%CI 0.21-0.63; P<0.001). And there was no significant difference discovered in objective response rate between low/negative and high/positive ERCC1 expression (RR 1.19; 95%CI 1.00-1.43; P=0.06). Evidence of modest heterogeneity was found between ERCC1 expression and OS (I(2)=48.8%, P<0.05) and subgroup analysis was performed based on ethnicity, variable methods and primary tumor location. The conclusion is that ERCC1 might be the one of adverse prognostic factors affecting the survival time and objective response to cisplatin-based chemoradiotherap due to its drug-resistance characteristics.

DNA repair biomarkers XPF and phospho-MAPKAP kinase 2 correlate with clinical outcome in advanced head and neck cancer

BACKGROUND

Induction chemotherapy is a common therapeutic option for patients with locoregionally-advanced head and neck cancer (HNC), but it remains unclear which patients will benefit. In this study, we searched for biomarkers predicting the response of patients with locoregionally-advanced HNC to induction chemotherapy by evaluating the expression pattern of DNA repair proteins.

METHODS

Expression of a panel of DNA-repair proteins in formalin-fixed paraffin embedded specimens from a cohort of 37 HNC patients undergoing platinum-based induction chemotherapy prior to definitive chemoradiation were analyzed using quantitative immunohistochemistry.

RESULTS

We found that XPF (an ERCC1 binding partner) and phospho-MAPKAP Kinase 2 (pMK2) are novel biomarkers for HNSCC patients undergoing platinum-based induction chemotherapy. Low XPF expression in HNSCC patients is associated with better response to induction chemoradiotherapy, while high XPF expression correlates with a worse response (p = 0.02). Furthermore, low pMK2 expression was found to correlate significantly with overall survival after induction plus chemoradiation therapy (p = 0.01), suggesting that pMK2 may relate to chemoradiation therapy.

CONCLUSIONS

We identified XPF and pMK2 as novel DNA-repair biomarkers for locoregionally-advanced HNC patients undergoing platinum-based induction chemotherapy prior to definitive chemoradiation. Our study provides insights for the use of DNA repair biomarkers in personalized diagnostics strategies. Further validation in a larger cohort is indicated.

ERCC1 expression and tumor regression predict survival in esophageal squamous cell carcinoma patients receiving combined trimodality therapy

PURPOSE

Combined trimodality therapy with neoadjuvant chemoradiation followed by surgery has shown promising results for locally advanced operable esophageal cancer. DNA repair proteins may affect treatment efficacy through repairing DNA damage induced by chemotherapy and radiation therapy. We evaluated the associations of XRCC1, ERCC1 and MGMT expression with histopathologic response and survival in patients with locally advanced operable esophageal squamous cell carcinoma (ESCC) who received neoadjuvant chemoradiation.

METHODS

Paraffin-embedded pre-treatment tissue samples, collected by endoscopic biopsy from patients treated with cisplatin-based neoadjuvant chemoradiation followed by surgery, were immunohistochemically stained for XRCC1, ERCC1 and MGMT expression.

RESULTS

Of the 44 patients, major histopathologic response was noted in 26 (59.1%) patients. 68.8% of patients with ERCC1-negative tumors had major histopathologic response, compared to 53.6% of those who expressed positive ERCC1, though the difference was not statistically significant (P=0.361). The patients with ERCC1-negative tumor presented much better overall survival than those positive for ERCC1 expression (P=0.018). Patients with major histopathologic response had a 3-year survival rate of 96.2% versus those with minor response, with a 3-year survival rate of 41.5% (P=0.000). Multivariate analysis showed that ERCC1 expression and histopathologic response were independent predictive factors of overall survival in patients with locally advanced operable ESCC receiving neoadjuvant chemoradiation.

CONCLUSION

Patients with ERCC1-negative tumors show a benefit from neoadjuvant chemoradiation, ERCC1 expression and tumor regression are useful predictive markers in patients with locally advanced operable ESCC receiving neoadjuvant chemoradiation followed by surgery.

Cell cycle association and hypoxia regulation of excision repair cross complementation group 1 protein (ERCC1) in tumor cells of head and neck cancer

Excision repair cross complementation group 1 (ERCC1) is a key component of homologous recombination-based repair of interstrand DNA cross-links (ICLs). As a consequence, ERCC1 mediates resistance to mitomycin C (MMC) and platinum chemotherapeutic agents and may predict treatment failure. Clinical response to MMC or cisplatin (CDDP)-based radiochemotherapy (RCT) was assessed in 106 head and neck squamous cell carcinoma (HNSCC) patients and correlated with cell nuclear immunoreactivity of the mouse monoclonal (clone: 8 F1) ERCC1 antibody in tumor tissue samples. BEAS-2B epithelial and Detroit 562 pharyngeal squamous carcinoma cells were treated with CDDP, MMC, and 5-fluorouracil (5-FU) at 50 % growth inhibitory (IC-50) concentrations. ERCC1 protein synthesis was compared with cell cycle distribution using combined immunocytochemistry and flow cytometry. ERCC1 messenger RNA (mRNA) and protein expression was investigated in normoxic and hypoxic conditions in Detroit 562 cells. Clinically, the nonresponder revealed significantly lower HNSCC tissue ERCC1 immunoreactivity than the responder (p = 0.0064) or control normal mucosa, which led to further mechanistic investigations. In vitro, control cells and cells treated with cytotoxic agents showed increasing ERCC1 levels from the G1 through S and G2 phases of the cell cycle. In CDDP-treated cells, ERCC1 mRNA and protein expression increased. Under hypoxic conditions, ERCC1 gene expression significantly decreased. Although ERCC1⁺ cells show increased chemoresistance, they might be particularly radiosensitive, representing G2 cell cycle phase and less hypoxic. ERCC1 expression might be indirectly related with some conditions important for RCT treatment, but it is not a clear predictor for its failure in HNSCC patients.

High level expression of AMAP1 protein correlates with poor prognosis and survival after surgery of head and neck squamous cell carcinoma patients

Background

Despite recent advances in cancer therapeutics in general, the survival of patients with head and neck squamous cell carcinomas (HNSCCs) has not improved substantially over the past few decades. HNSCC cells often exhibit invasive and metastatic phenotypes, and expression of epidermal growth factor receptor (EGFR) and cortactin has been highly implicated in the development of malignancy in HNSCCs. We have shown previously that an Arf6 pathway, in which Arf6 is activated by GEP100 and employs AMAP1 (also called DDEF1 or ASAP1) as its downstream effector, is pivotal for the invasion and metastasis of different breast cancer cells. This pathway is activated by receptor tyrosine kinases, including EGFR; and moreover, AMAP1 physically associates with cortactin, in which inhibition of this binding effectively blocks invasion and metastasis. We here investigated whether the expression of Arf6 pathway components correlates with the poor prognosis of HNSCC patients. We have shown previously that AMAP1 protein levels are not correlated with its mRNA levels, and hence we here employed immunohistochemical staining of HNSCC clinical specimens to investigate AMAP1 protein levels.

Results

We found that high levels of AMAP1 protein expression on its own, as well as its co-overexpression with EGFR statistically correlates with poor disease-free survival and poor overall survival, while high levels of cortactin expression or its co-expression with EGFR did not.

Conclusion

Our identification of predictive biomarkers, together with our previous findings on the coherent signaling pathway that these biomarkers ultimately generate should be powerful information for the further development of HNSCC therapeutics.

Genome stability pathways in head and neck cancers

Genomic instability underlies the transformation of host cells toward malignancy, promotes development of invasion and metastasis and shapes the response of established cancer to treatment. In this review, we discuss recent advances in our understanding of genomic stability in squamous cell carcinoma of the head and neck (HNSCC), with an emphasis on DNA repair pathways. HNSCC is characterized by distinct profiles in genome stability between similarly staged cancers that are reflected in risk, treatment response and outcomes. Defective DNA repair generates chromosomal derangement that can cause subsequent alterations in gene expression, and is a hallmark of progression toward carcinoma. Variable functionality of an increasing spectrum of repair gene polymorphisms is associated with increased cancer risk, while aetiological factors such as human papillomavirus, tobacco and alcohol induce significantly different behaviour in induced malignancy, underpinned by differences in genomic stability. Targeted inhibition of signalling receptors has proven to be a clinically-validated therapy, and protein expression of other DNA repair and signalling molecules associated with cancer behaviour could potentially provide a more refined clinical model for prognosis and treatment prediction. Development and expansion of current genomic stability models is furthering our understanding of HNSCC pathophysiology and uncovering new, promising treatment strategies.

ERCC1 is a prognostic biomarker in locally advanced head and neck cancer: results from a randomised, phase II trial

Background:

Cisplatin-radiotherapy is a preferred standard for locally advanced, head and neck squamous cell carcinoma (HNSCC). However, the cisplatin-attributable survival benefit is small and toxicity substantial. A biomarker of cisplatin resistance could guide treatment selection and spare morbidity. The ERCC1-XPF nuclease is critical to DNA repair pathways resolving cisplatin-induced lesions.

Methods:

In a phase II trial, patients with untreated Stage III-IVb HNSCC were randomised to cisplatin-radiotherapy with/without erlotinib. Archived primary tumours were available from 90 of 204 patients for this planned substudy. Semi-quantitative ERCC1 protein expression (H-score) was determined using the FL297, 4F9, and 8F1 antibodies. The primary analysis evaluated the relationship between continuous ERCC1 protein expression and progression-free survival (PFS). Secondary analyses included two pre-specified ERCC1 cutpoints and performance in HPV-associated disease.

Results:

Higher ERCC1 expression was associated with inferior PFS, as measured by the specific antibodies FL297 (HR=2.5, 95% CI=1.1–5.9, P=0.03) and 4F9 (HR=3.0, 95% CI=1.2–7.8, P=0.02). Patients with increased vs decreased/normal ERCC1 expression experienced inferior PFS (HR=4.8 for FL297, P=0.003; HR=5.5 for 4F9, P=0.007). This threshold remained prognostic in HPV-associated disease.

Conclusion:

ERCC1-XPF protein expression by the specific FL297 and 4F9 antibodies is prognostic in patients undergoing definitive cisplatin-radiotherapy for HNSCC, irrespective of HPV status.

A phase II study of biweekly paclitaxel and cisplatin chemotherapy for recurrent or metastatic esophageal squamous cell carcinoma: ERCC1 expression predicts response to chemotherapy

Recurrent or metastatic esophageal cancer has poor prognosis. This study was to assess the efficacy and safety of biweekly paclitaxel and cisplatin combination for patients with recurrent or metastatic esophageal squamous cell carcinoma. The excision repair cross-complementation group 1 (ERCC1) expression to predict response is also assessed. Forty-six eligible patients were enrolled. Paclitaxel was given at 150 mg/m(2) over 3 h on day 1, and cisplatin was given at 50 mg/m(2) on day 2, every 2 weeks as one cycle. ERCC1 protein expression was assessed by immunohistochemistry staining. The overall response rate was 56.5 % (26/46, 95 % CI 42.2-70.8 %). Progression-free survival was 5.6 months (95 % CI, 2.8-8.4 months), and the median actuarial survival time was 17.0 months (95 % CI, 12.3-21.7 months). There was a significant difference in median actuarial survival between the patients with a response compared to the non-responders (22.8 months vs. 7.4 months, P < 0.0001). Overall survival at 1 year was 65.0 %, and at 2 years was 34.0 %, respectively. The most frequent toxicity for all patients was neutropenia (37.0 and 23.9 % for grades 3 and 4, respectively). Patients with ERCC1 negative tumors had a higher treatment response than the ERCC1 positive group (radiological response rates; 92.3 % vs.50 %, P = 0.013). Biweekly chemotherapy with paclitaxel and cisplatin was found to be active and generally well tolerated. Our study indicates that the expression of ERCC1 evaluated by immunohistochemistry is a promising predictive marker for response in patients with metastatic ESCC receiving cisplatin-paclitaxel regimen.

Sunitinib synergizes the antitumor effect of cisplatin via modulation of ERCC1 expression in models of gastric cancer

We evaluated the effects of sunitinib monotherapy and in combination with cisplatin in human gastric cancer cell lines. Sunitinib showed antiproliferative effect in gastric cancer cells line with high PDGFRA expression. Knockdown of PDGFRA showed that sunitinib sensitivity was correlated with the basal expression of PDGFRA. Synergistic growth inhibitory activity in combination with cisplatin was identified. We further explored how sunitinib potentiated the activity of cisplatin. We found that sunitinib treatment resulted in the down-regulation of ERCC1 expression via the modulation of PDGFRA expression in gastric cancer cells. The effect was verified via SNU484 xenograft model. Our data support the rationale of clinical trial using sunitinib in combination of cisplatin in gastric cancer.