Independent evaluation of a FOXM1-based quantitative malignancy diagnostic system (qMIDS) on head and neck squamous cell carcinomas

Abstract

The forkhead box M1 (FOXM1) transcription factor gene has been implicated in almost all human cancer types. It would be an ideal biomarker for cancer detection but, to date, its translation into a cancer diagnostic tool is yet to materialise. The quantitative Malignancy Index Diagnostic System (qMIDS) was the first FOXM1 oncogene-based diagnostic test developed for quantifying squamous cell carcinoma aggressiveness. The test was originally validated using head and neck squamous cell carcinomas (HNSCC) from European patients. The HNSCC gene expression signature across geographical and ethnic differences is unknown. This is the first study evaluated the FOXM1-based qMIDS test using HNSCC specimens donated by ethnic Chinese patients. We tested 50 Chinese HNSCC patients and 18 healthy subjects donated 68 tissues in total. qMIDS scores from the Chinese cohort were compared with the European datasets (n = 228). The median ± SD scores for the Chinese cohort were 1.13 ± 0.66, 4.02 ± 1.66 and 5.83 ± 3.13 in healthy oral tissues, adjacent tumour margin and HNSCC core tissue, respectively. Diagnostic test efficiency between the Chinese and European datasets was almost identical. Consistent with previous European data, qMIDS scores for HNSCC samples were not influenced by gender or age. The degree of HNSCC differentiation, clinical stage and lymphatic metastasis status were found to be correlated with qMIDS scores. This study provided the first evidence that the pathophysiology of HNSCC was molecularly indistinguishable between the Chinese and European specimens. The qMIDS test robustly quantifies a universal FOXM1-driven oncogenic program, at least in HNSCC, which transcends ethnicity, age, gender and geographic origins.

Clinical correlation of opposing molecular signatures in head and neck squamous cell carcinoma

“…The use of fresh clinical specimens collected in the UK was approved by the NHS Research Ethics Committee (06/MRE03/69). All tissue samples were previously collected according to local ethical committee-approved protocols and informed patient consent was obtained from all participants [15, 16]. Fresh tissue biopsies were preserved in RNA Later (#AM7022, Ambion, Applied Biosystems, Warrington, UK) and stored short-term at 4 °C (1–7 days) prior to transportation and subsequent storage at − 20 °C until used.…”

Molecular markers associated with development and progression of potentially premalignant oral epithelial lesions: Current knowledge and future implications

“…For example, a number of reports have noted that molecular biomarkers for OSCC have been identified in apparently unaffected (both clinically and microscopically) surgical margins and have been shown to be discordant with histopathologic dysplasia grading. [17][18][19] Therefore, there is an ongoing quest for the discovery of molecular markers that may reflect the premalignant nature of a lesion, not only with greater predictive ability but also, ideally, before the development of the corresponding clinicopathologic alterations.…”

“…140,142,143 Furthermore, expression of FOXM1 has been shown to target the epigenetic/stem cell modulator HELLS during cancer initiation, 140,144 which is a downstream target of FOXM1 in head and neck SCC (HNSCC). 17,145 In normal human oral keratinocytes (NOK), upregulation of FOXM1, via HELLS and the DNA methyltransferases DNMT1 and DNMT3 B, suppresses p16 INK4 A through promoter hypermethylation. The dose-dependent upregulation of endogenous FOXM1 (isoform B) expression during tumor progression across a panel of normal primary NOK, dysplasia, and HNSCC cell lines correlates positively with endogenous expression of HELLS, BMI1, DNMT1, and DNMT3 B and negatively with p16 INK4 A and involucrin.…”

Retinoids induce antagonism between FOXO3A and FOXM1 transcription factors in human oral squamous cell carcinoma (OSCC) cells

“…Since FOXM1 overexpression induces neoplastic transformation of breast epithelia [41], prostate epithelia [42], non-small cell lung cancer-derived cells [43], and oral cavity and esophageal epithelia [11, 14], we silenced FOXM1 expression by introducing FOXM1-targeting short-hairpin RNAs (shRNA) into SCC-25 cells (S1B Fig). We conducted cell proliferation assays of the SCC-25 parental line, SCC-25 cells that stably express the empty vector pLKO, SCC-25 cells that express a scrambled FOXM1 shRNA construct (shFOXM1 SCR), and SCC-25 cells that express a shRNA construct targeting FOXM1 (shFOXM1 #3) (Fig 4B).…”

“…We and others have shown increased FOXM1 transcript and protein levels in the oral cavity during the development and progression of OSCC in both murine carcinogenesis models and human patient samples [9–13]. Additionally, FOXM1 is a prognostic factor for oral [14] and esophageal squamous cell carcinoma [15, 16]. The oncogenic effects of FOXM1 generally are mediated through the phosphorylation of cyclin E-CDK2 and Raf-MEK-ERK signaling cascades that cause the nuclear translocation of FOXM1 [17, 18].…”