FHIT Oncosuppressor Gene Expression Profile in Human Anal Cancers

DNA methylation profiling across the spectrum of HPV-associated anal squamous neoplasia

BACKGROUND

Changes in host tumor genome DNA methylation patterns are among the molecular alterations associated with HPV-related carcinogenesis. However, there is little known about the epigenetic changes associated specifically with the development of anal squamous cell cancer (SCC). We sought to characterize broad methylation profiles across the spectrum of anal squamous neoplasia.

METHODOLOGY/PRINCIPAL FINDINGS

Twenty-nine formalin-fixed paraffin embedded samples from 24 patients were evaluated and included adjacent histologically normal anal mucosa (NM; n = 3), SCC-in situ (SCC-IS; n = 11) and invasive SCC (n = 15). Thirteen women and 11 men with a median age of 44 years (range 26-81) were included in the study. Using the SFP(10) LiPA HPV-typing system, HPV was detected in at least one tissue from all patients with 93% (27/29) being positive for high-risk HPV types and 14 (93%) of 15 invasive SCC tissues testing positive for HPV 16. Bisulfite-modified DNA was interrogated for methylation at 1,505 CpG loci representing 807 genes using the Illumina GoldenGate Methylation Array. When comparing the progression from normal anal mucosa and SCC-IS to invasive SCC, 22 CpG loci representing 20 genes demonstrated significant differential methylation (p<0.01). The majority of differentially methylated gene targets occurred at or close to specific chromosomal locations such as previously described HPV methylation "hotspots" and viral integration sites.

CONCLUSIONS

We have identified a panel of differentially methlylated CpG loci across the spectrum of HPV-associated squamous neoplasia of the anus. To our knowledge, this is the first reported application of large-scale high throughput methylation analysis for the study of anal neoplasia. Our findings support further investigations into the role of host-genome methylation in HPV-associated anal carcinogenesis with implications towards enhanced diagnosis and screening strategies.

Restoration of fragile histidine triad (FHIT) expression inhibits cell growth and induces apoptosis in cutaneous T-cell lymphoma cell line

To investigate the effects of fragile histidine triad (FHIT) restoration on cell proliferation and apoptosis in human cutaneous T-cell lymphoma cell line, Hut-78, in vitro and in nude mouse. Wild-type FHIT gene was transfected by liposome into the Hut-78 cells. The alteration of cell growth curve and soft agar colony formation was studied in vitro and in nude mice. The FHIT gene was stably expressed in Hut-78 cells after the transfection. Compared with the controls, restoration of FHIT expression inhibited cell growth and induced apoptosis. Tumor formation in vivo was strongly suppressed by FHIT gene restoration. Our data demonstrate restoration of FHIT gene expression inhibit the tumor cell growth and provide an option for the treatment.