Molecular and Clinical Implications of Somatostatin Receptor Profile and Somatostatin Analogues Treatment in Oral Cavity Squamous Cell Carcinoma

Expression of KITENIN and its association with tumor progression in oral squamous cell carcinoma

BackgroundLong noncoding RNAs (lncRNAs) are widely involved in cancer development and progression, but the functions of most lncRNAs have not yet been elucidated. Metastasis is the main factor restricting the therapeutic outcomes of various cancer types, including oral squamous cell carcinoma (OSCC). Therefore, exploring the key lncRNAs that regulate OSCC metastasis and elucidating their molecular mechanisms will facilitate the development of new strategies for effective OSCC therapy.MethodsWe analyzed the lncRNA expression profiles of tumor tissues from OSCC patients with and without cervical lymph node metastasis, and OSCC cell lines. We revealed high expression of oral squamous cell carcinoma metastasis-related lncRNA 1 (lncOCMRL1) in OSCC patient tumor tissues with lymph node metastasis and highly metastatic OSCC cell lines. The effects of lncOCMRL1 knockdown on the invasion, migration and proliferation abilities of OSCC cells were explored through qRT-PCR, Transwell, colony formation, and cell proliferation experiments. The mechanism by which lncOCMRL1 promotes OSCC metastasis and proliferation was explored through RNA pull-down, silver staining, mass spectrometry, RIP, and WB experiments. To increase its translational potential, we developed a reduction-responsive nanodelivery system to deliver siRNA for antitumor therapy.ResultsWe determined that lncOCMRL1 is highly expressed in OSCC metastatic tumor tissues and cells. Functional studies have shown that high lncOCMRL1 expression can promote the growth and metastasis of OSCC cells both in vivo and in vitro. Mechanistically, lncOCMRL1 could induce epithelial-mesenchymal transition (EMT) via the suppression of RRM2 ubiquitination and thereby promote the proliferation, invasion, and migration of OSCC cells. We further constructed reduction-responsive nanoparticles (NPs) for the systemic delivery of siRNAs targeting lncOCMRL1 and demonstrated their high efficacy in silencing lncOCMRL1 expression in vivo and significantly inhibited OSCC tumor growth and metastasis.ConclusionsOur results suggest that lncOCMRL1 is a reliable target for blocking lymph node metastasis in OSCC.

Environmental exposure to carcinogens causes mucosal damage in the upper aerodigestive tract, which can lead to cancers. The genetic basis of head and neck cancer is controversial. To identify susceptibility genes in head and neck cancers, we enrolled patients with early-onset disease in Taiwan. This case-control study included 54 young male patients with oral squamous cell carcinoma (OSCC) who were treated between March 1996 and December 2016, as well as 2,400 healthy controls. A single-nucleotide polymorphism (SNP) array was used to determine genetic loci that increase susceptibility to OSCC. Sequencing-based typing (TBG Biotechnology Corp., Taipei, Taiwan) was used to determine the HLA-DQB1 genotype in another cohort of 147 OSCC patients. We analyzed the allele frequencies of 664,994 autosomal SNPs in the 54 OSCC cases. In a genome-wide association analysis, four SNPs within loci on chromosomes 6, 7, 9, and 12 were significantly different between OSCC patients and controls (corrected P < 1.0 × 10−6). HLA-DQB1 was closest to rs28451423 on chromosome 6. HLA-DQB1*05:02 in OSCC (18.5%) was significantly different from normal population (7.0%) (P = 0.009). The influence of disease onset was independently significant after adjusting cigarette smoking, alcohol drinking and areca-quid chewing (P = 0.015, OR: 3.922, 95% confidence interval: 1.311 - 11.734). Furthermore, HLA-DQB1*05:02 was associated with early-onset OSCC (P = 0.004). HLA-DQB1*05:02 is associated with OSCC independent of environmental exposures. HLA-DQB1*05:02 is also related with early onset of OSCC. It provides evidence of a genetic basis for OSCC. Citation Format: Shiang-Fu Huang, Huei-Tzu Chien, Chi-Kuan Young, Yun-Shien Lee, Chun-Ta Liao, Kai-Lun Cho, Ching-Han Chen. HLA-DQB1*05:02: An independent genetic marker for oral cavity squamous cell carcinoma susceptibility [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 2 (Late-Breaking, Clinical Trial, and Invited Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(7_Suppl):Abstract nr LB379.

Squamous cell carcinoma antigen (SCC-Ag) and C-reactive protein (CRP) levels have been successfully used to stratify risk groups in primary oral squamous cell carcinoma (OSCC) patients; however, related biomarkers have rarely been investigated in recurrent OSCC. The purpose of the present study was to analyze the relationships of SCC-Ag and CRP levels at the time of recurrence with clinical factors and prognosis. We retrospectively recruited patients with recurrence in a cohort of 534 OSCC patients between March 2001 and July 2013. One hundred patients had recurrence. The serum SCC-Ag and CRP levels were measured at the time of cancer diagnosis, 3 to 6 months after treatment with clinical disease-free, and at the time of recurrence. The SCC-Ag levels were significantly lowered after treatment (paired t-test: p = 0.001) and re-elevated at the time of recurrence (paired t-test: p = 0.027). An SCC-Ag level ≥2.0 ng/ml and a CRP level ≥5.0 mg/L at the time of recurrence were significantly associated with recurrent tumor status (P<0.001), recurrent nodal metastasis (χ2 trend test: P = 0.020), distant metastasis (P<0.001), and overall survival (P<0.001). Moreover, the influence of both elevated SCC-Ag and CRP levels on overall survival (P<0.001, H.R. [95% CI]: 5.406 [2.210–13.222]) still existed after adjusting for the recurrent tumor stage and patient age. The present study demonstrates that concurrent high levels of both SCC-Ag and CRP at the diagnosis of recurrence acts as a predictor of recurrent tumor status, recurrent advanced tumor stage, distant metastasis, and survival after the diagnosis of recurrence. This study expands the applicability of these two markers in the risk stratification in recurrent OSCC.

Background:Oral squamous cell carcinoma (OSCC) is an aggressive cancer whose 5-year survival rate remains poor. San-Zhong-Kui-Jian-Tang (SZKJT), a Chinese herbal formula, has long been used in clinical practice as adjuvant therapy in cancers. However, its therapeutic effects and molecular mechanisms in OSCC remain unclear.Methods:We investigated the potential therapeutic effects and molecular mechanism of SZKJT in OSCC in tumor cell lines and in tumor xenograft mice and evaluated combined SZKJT and cisplatin treatment efficacy. In vitro-cultured OSCC cells were administered SZKJT at different doses or SZKJT plus cisplatin, and cell proliferation, colony formation assays, and cell cycle analysis were used to assess the effects on cancer cell proliferation and apoptosis. We also analyzed the effects of SZKJT on oral cancer cell line migration, the regulation of mitogen-activated protein kinase (MAPK) signaling, and epithelial-mesenchymal transition (EMT)-associated genes. The antitumor effects of SZKJT plus cisplatin were also tested in vivo using a tumor-bearing NOD/SCID mice model.Results:The results showed that SZKJT effectively inhibited OSCC cell proliferation, induced cell cycle S phase arrest, and induced cell apoptosis. SZKJT also inhibited cell migration by modulating the MAPK signaling and epithelial-mesenchymal transition (EMT) pathway. Further exploration suggested that SZKJT affects OSCC by modulating ERK pathway; downregulating vimentin, fibronectin, and Oct-4; and upregulating E-cadherin. In vivo, SZKJT significantly inhibited tumor growth, and SZKJT and cisplatin exerted synergistic antitumor effects in model animals.Conclusions:SZKJT exerts antitumor effects in OSCC cells. Additionally, SZKJT and cisplatin exhibit synergy in OSCC treatment. These findings support the clinical usage of Chinese herbal formulas as adjuvant therapy with chemotherapy in cancer treatment.

Background: Oral cavity malignancy can result from surface epithelium, salivary glands, or submucosal soft tissue. Common symptoms may include non-healing ulcers, slurred speech, dysphagia, neck mass and pain which may indicate cortical invasion. Morbidity and quality of life have been seen to rise with mandibular excision in oral cavity squamous cell carcinoma. Therefore, in order to design the surgery appropriately, it is vital to be aware of the mandibular invasion prior to the procedure. Various researches have been focused on the accuracy of clinical examination and imaging technique in predicting tumour invasion of the mandible in oral malignancy. The goal of this study was to find a correlation between histological assessment, clinical examination, and computed tomography results in patients with mandibular involvement and oral cavity squamous cell carcinoma. Objectives: To determine the sensitivity, specificity, NPV and PPV of CECT and clinical diagnosis in patients with oral squamous cell carcinoma with mandibular invasion. Methods: A cross-sectional observational study was set out to review preoperative clinical and radiological assessment; and post operative histopathological finding of mandibular resection specimen in clinically evaluated and diagnosed cases of oral cavity squamous cell carcinoma (SCC) with mandibular invasion. Results: 43 individuals of oral cavity SCC with mandibular involvement were examined. 12 out of 28 mandibular resections had bone invasion, with numerous tumour entry sites being the most frequent mechanism of invasion, according to post-operative HPE. The positive predictive value (PPV) of contrast enhanced computerised tomography (CECT) scans was 42.8%, as 28 individuals had invasions revealed; sensitivity is almost 100%; specificity is 48.3. Conclusion: Prioritizing the identification of mandibular invasion is essential to enhance the prognosis of patients with oral SCC. There is an urgent necessity to review the usefulness of radiology in the treatment of mandibulectomy. Combination of clinical and radiological examination increases sensitivity and specificity.

Simple SummaryOral squamous cell carcinoma (OSCC) is the most widespread malignancy of the head and neck and is characterized by a high potential for local invasion and lymph node metastasis. Serum response factor (SRF) regulates pro-carcinogenic genes in various cancers, but its role in OSCC remains unclear. The present study is the first to elucidate the role of SRF in OSCC development to our knowledge. We revealed that SRF is overexpressed in patients with OSCC, which is correlated with the depth of invasion and lymph node metastasis. Tumorigenicity assays in nude mice further proved that SRF promoted OSCC tumorigenesis in vivo. In addition, overexpressed SRF regulated the novel IDO1/Kyn-AhR signaling pathway to enhance OSCC cell migration and invasion by modulating EMT. In conclusion, we revealed a novel molecular mechanism by which SRF modulates OSCC metastasis. Our study could provide potential targets or biomarkers for OSCC diagnosis and treatment.Serum response factor (SRF) regulates pro-carcinogenic genes in various cancers, but its role in oral squamous cell carcinoma (OSCC) remains unclear. SRF expression in 70 OSCC samples was detected via immunohistochemistry. Abundant SRF expressed in OSCC tissues was closely associated with tumor metastasis. SRF-overexpressing OSCC cells were constructed to evaluate how SRF affects OSCC cell tumorigenesis and epithelial-to-mesenchymal transition (EMT) in vitro and in vivo. Overexpressed SRF increased OSCC cell migration and invasion in vitro and tumor growth and invasion in vivo. This promoted EMT, characterized by decreased and increased expression of E- and N-cadherin, respectively. Furthermore, an analysis of RNA sequences of transcriptional targets of SRF showed that SRF transactivated the indoleamine 2, 3-dioxygenase 1 (IDO1)/kynurenine-aryl hydrocarbon receptor (Kyn-AhR) signaling pathway in OSCC cell lines. Direct SRF binding to the IDO1 gene promoter upregulated transcription, which was detected through chromatin immunoprecipitation and dual luciferase reporter assays. Inhibiting IDO1 or AhR impaired SRF-induced migration and invasion and prevented EMT in OSCC cells. Our results demonstrated that SRF is a critical regulator of the IDO1/Kyn-AhR signaling pathway. This in turn increases OSCC cell migration and invasion by modulating EMT, which, consequently, favors OSCC cell growth and metastasis. We revealed a novel molecular mechanism through which SRF modulates OSCC metastasis. This should provide potential targets or biomarkers for OSCC diagnosis and treatment.

The overall 5-year survival for oral squamous cell carcinoma (OSCC) has not changed in the last 20 years despite advances in treatment. Lymphovascular invasion (LVI) has been shown to be a negative prognostic factor in other cancers, however its role in the prognosis of OSCC remains unclear. This study aims to determine if LVI is a predictor of cervical lymph node metastasis and/or recurrence in OSCC. We conducted a retrospective cohort review of patients from our institutional cancer registry who were treated for OSCC between 2004 and 2018. Patient demographics, surgical pathology results, and clinical outcome data were collected. A multivariable logistic regression analysis was performed to determine if LVI was an independent predictor of cervical lymph node metastasis and/or recurrence. 442 patients were included, 32.8% were female and median age at time of diagnosis was 61.2 years. LVI was present in 32.8% of patients. When controlled for age, sex, t-classification, perineural invasion, depth of invasion (DOI), and margin status, LVI was a significant predictor of the presence of cervical node metastasis (OR: 3.42, CI: 2.17-5.39, P < .001). There was no significant association found between LVI and local recurrence (OR: 1.03, CI: 0.57-1.84, P = .92), regional recurrence (OR: 1.10, CI: 0.57-2.11, P = .78), or distant recurrence (OR: 1.59, CI: 0.87-2.94, P = .13). The results of this study suggest that LVI is a significant predictor of the presence of cervical lymph node metastasis at presentation independent of other known prognostic factors. LVI, however, was not found to be a significant independent predictor of locoregional or distant recurrence.Level of Evidence: Level III.

Human Papillomavirus E6/E7 mRNA detection by in situ hybridization in oral cavity squamous cell carcinoma

Photodynamic therapy in the treatment of oral squamous cell carcinoma - The state of the art in preclinical research on the animal model.

MicroRNAs (miRNAs/miR) often contribute to the progression of oral squamous cell carcinoma (OSCC) via the regulation of mRNA. The present study aimed to investigate the role of miR-198 in OSCC pathogenesis and explore the underlying mechanism. Reverse transcription-quantitative (RT-q)PCR was performed to determine miR-198 expression in OSCC tissues and cell lines, and univariate and multivariate analyses were applied to evaluate the survival of patients with OSCC. The effects of miR-198 on OSCC cell lines were studied in vitro and in vivo. A set of epithelial-mesenchymal transition (EMT) markers were detected to determine whether miR-198 was involved in EMT. Lastly, using luciferase assays, a novel target of miR-198 was identified and the effect of the new target gene of miR-198 on cell proliferation and invasion was also studied. It was identified that miR-198 expression was decreased in OSCC tissues and cell lines, and low expression of miR-198 was associated with poor overall survival and disease-free survival. Overexpression of miR-198 appeared to significantly inhibit the proliferation, invasion and EMT of OSCC cells. Moreover, the luciferase assay results showed that miR-198 interacted with cyclin-dependent kinase 4 (CDK4) by directly targeting the miRNA-binding site in the CDK4 sequence, and RT-qPCR results showed that CDK4 expression was increased in OSCC tissues and cell lines. In addition, transfection of small interfering RNA against CDK4 in OSCC cells showed similar inhibitory effects on cell proliferation, invasion and EMT, whereas CDK4 overexpression in OSCC cells partially reversed the inhibitory effects of the miR-198 mimic. The present results indicated that miR-198 suppressed OSCC tumour growth and metastasis by directly targeting CDK4 expression. Thus, miR-198 may be a potential therapeutic target in the treatment of OSCC.

Huntingtin (HTT) is one of the target genes of miR-146-a and regulates various cancer cell activities. This study aims to explore the miR-146a expression pattern in oral squamous cell carcinoma (OSCC) and its role and mechanism in OSCC progression and metastasis via targeting the HTT gene. OSCC tissue and non-cancerous matched tissue (NCMT) were obtained from 14 patients. OSCC cell lines and normal HOK cells were used to analyze migration and invasion assay. OSCC-induced miR-146a knockout mice (B6.Cg-Mir146tm1.1Bal) model was developed. Transwell cell migration/invasion and scratch wound assays were used to investigate the OSCC cell migration and invasion in vitro. Kaplan-Meier survival analysis was used to investigate the association of HTT expression patterns in cancer tissue with patient survival percentage and duration. Pearson’s correlation analysis tested the association between miR-146a and HTT expression in OSCC tissues. miR-146a mimic and inhibitor transfection were performed to overexpress and knockdown the miR-146a in OSCC cells, respectively. miR-146a expression was highly upregulated in OSCC tissues and OSCC cell lines. Cancer cell migration/invasion was enhanced in miR-146a overexpressed cells and reduced in mi-R146a knockdowned cells. HTT expression was reduced in OSCC tissues and cell lines compared to NCMT and HOK cells, respectively. HTT expression was downregulated in miR-146a overexpressed OSCC cells and upregulated in miR-146a knockdowned OSCC cells. The expression pattern of miR-146a in OSCC cell lines and tissues was inversely correlated with HTT expression. Prediction of miRNA target analysis showed that HTT possesses the binding sites for miR-146a. HTT overexpression in OSCC tissues was associated with patients’ higher survival percentage and duration. HTT knockdown in OSCC cells enhanced miR-146a expression and cell migration/invasion. Inducing OSCC in miR-146a knockout mice increased the HTT expression in tongue tissue and alleviated the cancer aggressiveness and epithelial damage. Overexpressed miR-146a in OSCC targets the HTT gene and enhances cancer cell migration/invasion unraveling the possible role of HTT in miR146a-mediated OSCC cell migration and invasion.

A histopathologic comparison between synchronous and single primary oral squamous cell carcinomas

miR-223 regulates oral squamous cell carcinoma metastasis through the Wnt/β-catenin signaling pathway.

Background: The objective of surgical management of oral squamous cell carcinoma (OSCC) is adequate resection with a clear margin. However, there is still a debate as to the optimal length for a mandibular resected margin. Objective: To examine the length of peri-neural spreading in T4 mandibular invaded oral cavity squamous cell carcinoma. Materials and Methods: Twenty-eight T4 pathological OSCC specimens that involved mandible and serial slices were studied and the length of tumor spreading along the inferior alveolar nerve (IAN) was determined. Tumor characteristics, risk factors, and survival were analyzed. Results: The incidence of peri-neural invasion was 11.11%, and IAN invasion was found in 14.29% of the tumor-invaded mandibular marrow. The length of tumor spreading along IAN was 3 to 12 mm. Poor prognostic factors of T4 OSCC were it being located on the tongue (HR 14.16), was pathological N2-3 (HR 31.05), and had high-risk features such as peri-neural invasion, lymphovascular invasion, and extra-nodal extension. Conclusion: A mandibular resected margin of at least 18 mm is recommended as a clear surgical margin in cases of T4 mandibular invasion OSCC. Keywords: Oral cancer, Perineural invasion, Inferior alveolar nerve, Squamous cell carcinoma, Mandibulectomy