乙酰肝素酶与头颈部鳞状细胞癌侵袭、转移和血管生成的关系

目的 探讨乙酰肝素酶(HPA)mRNA与头颈部鳞状细胞癌(HNSCCs)侵袭、转移和血管生成之间的关系.方法 应用逆转录-聚合酶链反应(RT-PCR)技术检测HPA mRNA在70例HNSCCs组织、20例癌旁黏膜组织中的表达情况,免疫组织化学染色(SP法)检测70例HNSCCs组织中CD34的表达情况,并结合HNSCCs临床病理特征,分析HPA mRNA与HNSCCs侵袭,转移和肿瘤微血管密度(MVD)之间的关系.结果 70例HNSCCs组织中HPA mRNA阳性表达41例,30例癌旁组织中仅3例HPA mRNA呈微弱表达,不同组织中HPA的表达差异有统计学意义(P＜0.05).HPA mRNA阳性表达与HNSCCs病理分级、侵袭程度和颈淋巴结转移有关(P＜0.05),即原发肿瘤分化程度越差、侵袭程度越深,HPA阳性表达率就越高;有颈淋巴结转移者HPA阳性表达率显著高于无颈淋巴结转移者.HPA mRNA阳性者的MVD值(57.65±4.46)显著高于阴性者(35.23±4.16,P＜0.05).结论 HPA促进HNSCCs的侵袭、转移和血管生成,可作为反应HNSCC生物学行为的客观指标.     

Loss of expression of ZAC/LOT1 in squamous cell carcinomas of head and neck

BACKGROUND: ZAC/Lot1 is a previously identified candidate tumor suppressor gene. The gene maps to the human chromosome 6q24-q25, a region frequently deleted in squamous cell carcinomas of the head and neck and other solid tumors. METHODS: We have used a model of head and neck squamous cell carcinoma (HNSCC) and cell lines to analyze the role of the candidate tumor suppressor gene ZAC/Lot1 in oral carcinogenesis. We analyzed the expression in 11 cell lines, and we performed loss of heterozygosity (LOH)- and sequence analyses in 51 primary tumors. RESULTS: Three (27.3%) of 11 cell lines showed a distinctly reduced expression of ZAC/Lot1 compared with expression levels of the gene in the normal oral mucosa. In addition, we analyzed 51 primary squamous cell carcinomas of the head and neck for LOH with seven microsatellite markers flanking ZAC/Lot1. We detected an average LOH rate of 31.4% in the region of interest. Sequence analysis revealed no mutations for the ZAC/Lot1 coding exons, including the exon/intron boundaries. CONCLUSIONS: These data could suggest a minimal role for ZAC/Lot1 in a subgroup of HNSCC tumors.     

Loss of imprinting and loss of heterozygosity on 11p15.5 in head and neck squamous cell carcinomas

BACKGROUND: IGF2 and H19 are reciprocal imprinted genes with paternal and maternal monoallelic expression, respectively. This is interesting, because IGF2 is known as a growth factor, and H19 encodes a RNA with putative tumor suppressor action. Furthermore, IGF2 and H19 are linked genes located on chromosome 11p15.5, a common site of loss of heterozygosity in human cancers. METHODS: We performed an allelic-typing assay using a PCR-RFLP-based method for identification of heterozygous informative cases in head and neck squamous cell carcinomas. Tumoral total RNA was extracted from each of the heterozygotes and further studied by RT-PCR analysis. RESULTS: We detected the expression of the IGF2 gene in 10 of 10 informative cases. Two cases exhibited LOI of the IGF2 gene as evidenced by biallelic expression, and in another case, LOH was coupled with monoallelic expression of this growth factor. LOI for the H19 gene was observed in 1 of 14 informative samples analyzed. In this case, we also detected parallel monoallelic expression of the IGF2 gene. Down-regulation of the H19 gene was observed in 10 of 14 cases. CONCLUSION: These findings support the hypothesis that H19 may be a tumor suppressor gene involved in head and neck carcinogenesis. Furthermore, our data showed that genetic and epigenetic changes at 11p15.5 could lead to abnormal expression of imprinted genes in HNSCC.     

The role of head and neck cancer advocacy organizations during the COVID‐19 pandemic

The COVID‐19 pandemic has had a significant impact on many aspects of head and neck cancer (HNC) care. The uncertainty and stress resulting from these changes has led many patients and caregivers to turn to HNC advocacy groups for guidance and support. Here we outline some of the issues being faced by patients with HNC during the current crisis and provide examples of programs being developed by advocacy groups to address them. We also highlight the increased utilization of these organizations that has been observed as well as some of the challenges being faced by these not‐for‐profit groups as they work to serve the head and neck community.     

Defects in G1-S cell cycle control in head and neck cancer: a review

Tumors gradually develop as a result of a multistep acquisition of genetic alterations and ultimately emerge as selfish, intruding and metastatic cells. The genetic defects associated with the process of tumor progression affect control of proliferation, programmed cell death, cell aging, angiogenesis, escape from immune control and metastasis. Fundamental cancer research over the last thirty years has revealed a multitude of genetic alterations which specify more or less separate steps in tumor development and which are collectively responsible for the process of tumor progression. The genes affected play in normal cells a crucial role in control over cell duplication and the interaction between cells, and between cells and their direct surrounding. This is illustrated on control during the G1/S phase of the cell cycle by its ultimate regulators: cyclins and cyclin dependent kinases. These proteins not only control the transition through the G1/S phase of the cell cycle, but also serve as mediators of the interaction between cells, and between cells and their surrounding. Defaults in the regulation of these proteins are associated with tumor progression, and, therefore, serve as targets for therapy. Defaults in those genes are found in various tumor types, although some of those prevail in particular tumor types. In this review emphasis is given to the defaults that occur in head and neck cancer.