Fingerprinting genomic instability in oral submucous fibrosis

Background:  Oral submucous fibrosis (OSF) is a high-risk pre-cancerous condition where 7–13% of these patients develop head and neck squamous cell carcinoma (HNSCC). To date there is no cancer predictive markers for OSF patients. Genomic instability hallmarks early genetic events during malignant transformation causing loss of heterozygosity (LOH) and chromosomal copy number abnormality. However, to date there is no study on genomic instability in OSF. Although this condition is known as a high-risk pre-cancerous condition, there is no data regarding the genomic status of this disease in terms of genetic susceptibility to malignant transformation.
Methods:  In this study, we investigated the existence of genetic signatures for carcinogenesis in OSF. We employed the high-resolution genome-wide Affymetrix Mapping single nucleotide polymorphism microarray technique to 'fingerprint' global genomic instability in the form of LOH in 15 patient-matched OSF–blood genomic DNA samples.
Results:  This rapid high-resolution mapping technique has revealed for the first time that a small number of discrete hot-spot LOH loci appeared in 47–53% of the OSF tissues studied. Many of these LOH loci were previously identified regions of genomic instability associated with carcinogenesis of the HNSCC.
Conclusion:  To our knowledge, this is the first evidence that genomic instability in the form of LOH is present in OSF. We hypothesize that the genomic instability detected in OSF may play an important role in malignant transformation. Further functional association studies on these putative genes may reveal potential predictive oral cancer markers for OSF patients.     

Feasibility of ureter delineation and dose recording in the assessment of ureteric stenosis during brachytherapy for cervical cancer

INTRODUCTIONUreteric stenosis is the commonest complication to affect the ureter after radiotherapy for cervical cancer; despite this ureters are not contoured as organs at risk and limited dosimetric data exist for them.METHODS/MATERIALSBilateral ureters were retrospectively delineated on brachytherapy planning imaging for patients treated for cervical cancer between 2014 and 2019. Ureteric stenosis toxicity data and D2cc, D1cc, D0.1cc of the right and left ureter were collated. Ureter V80, V100, V120, and V150 were also analyzed. Univariate analysis was performed to identify predictors of high ureter dose and ureteric stenosis.RESULTS95 patients were identified and 190 ureters contoured on brachytherapy planning imaging, with a median follow-up duration of 24 months (IQR23.7). 4.2% (4) of patients had grade 3/4 ureteric stenosis. Mean ureter D0.1cc, D1.0cc and D2.0cc on the right were 80.4Gy (±28.9), 56.2Gy (±7.2) and 52.8Gy (±7.6), and on the left were 75.6Gy (±14.6), 54.3Gy (±5.5) and 52.7Gy (±5.5) respectively. Significantly higher ureter doses were present in patients with baseline hydronephrosis (p < 0.002) and interstitial needle use (p = 0.047). Ureters affected by ureteric stenosis received D0.1cc doses between 60-98Gy. 10-14% received point doses in excess of 150% of the prescribed dose (7Gy) with no resulting ureteric stenosis. No significant difference in D0.1cc was found in patients with or without ureteric stenosis.CONCLUSIONSIt is feasible to accurately contour ureters on brachytherapy planning imaging. Baseline hydronephrosis and interstitial needle use contribute to higher ureter doses. No association between dose and ureteric stenosis was found.     

Thyroid-stimulating hormone (TSH)-directed induction of the CREM gene in the thyroid gland participates in the long-term desensitization of the TSH receptor.

Thyroid gland function is regulated by the hypothalamic-pituitary axis via the secretion of TSH, according to environmental, developmental, and circadian stimuli. TSH modulates both the secretion of thyroid hormone and gland trophism through interaction with a specific guanine nucleotide-binding protein-coupled receptor (TSH receptor; TSH-R), which elicits the activation of the cAMP-dependent signaling pathway. After TSH stimulation, the levels of TSH-R RNA are known to decrease dramatically within a few hours. This phenomenon ultimately leads to homologous long-term desensitization of the TSH-R. Here we show that TSH drives the induction of the inducible cAMP early repressor (ICER) isoform of the cAMP response element (CRE) modulator gene both in rat thyroid gland and in the differentiated thyroid cell line FRTL-5. The kinetics of ICER protein induction mirrors the down-regulation of TSH-R mRNA. ICER binds to a CRE-like sequence in the TSH-R promoter and represses its expression. Thus, ICER induction by TSH in the thyroid gland represents a paradigm of the molecular mechanism by which pituitary hormones elicit homologous long-term desensitization.     

Serum markers of immune activation and liver allograft rejection

We monitored the immune response after liver transplantation in 20 patients by measuring the serum levels of soluble interleukin-2 receptor (sIL-2R), soluble CD8 (sCD8), serum amyloid-A protein (SAA), and tumor necrosis factor- (TNF-). In six patients data were available to extend the follow-up period to one year. In all patients mean sIL-2R levels increased in the first month after liver transplantation, and subsequently decreased to values similar to pre-OLT ones, while SAA mean levels rose in the first week after OLT only in patients with rejection. sCD8 levels did not significantly rise after OLT, and TNF- was undetectable in most cases. During episodes of rejection, rejector patients had significantly higher levels of sIL-2R, sCD8, and SAA than stable (without complications) patients. Conversely, no significant difference between rejectors and patients with other complications existed for any of the markers studied. These results diminish the importance of these serum markers of immune activation as laboratory tools in the differential diagnosis of acute rejection from other complications. However, sIL-2R, SAA, and sCD8 levels correlated with the histological grade of rejection and therefore can be utilized to monitor patients with an established diagnosis of acute rejection.     

Flow Cytometry and In Vitro Tritiated Thymidine Labeling in Normal Rectal Mucosa of Patients at High Risk of Colorectal Cancer

Objectives : To compare two different methods to evaluate rectal epithelial cell proliferation as a hio-marker of risk of developing colon cancer. Methods : Samples of normal rectal mucosa from 26 patients at increased risk for colorectal cancer (22 patients with adenoma, three with adenocarcinoma ofthe large bowel, and one with longstanding ulcerative colitis) were ex-amined by means of in vitro labeling with tritiated thymidine and flow cytometry. Results : We found a signiHcant correlation between thymidine-labeling in-dex and the percentage of cells in S-phase, measured by flow cytometry both in formalin-fixed, paraffin-em-bedded specimens and in frozen specimens (respec-tively, r= 0.7647, p < 0.001, and r = 0.4503, p < 0.01). However, using flow cytometry, the percentage of cells in S-phase was significantly higher than the thymidine-labeling index in both fixed-embedded and frozen spec-imens ip < 0.01). ProHferative parameters were not higher in patients with colon carcinoma, and were not related to the degree of dysplasia, the number of ade-nomas, or familial occurrence of colorectal cancer. Two specimens taken from normal rectal mucosa of two patients with adenomas showed aneuploidy. No aneu-ploidy was found in normal rectal specimens of patients with adenocarcinoma. Conclusions: These results show that the calculation of cells in S-phase with in vitro tritiated thymidine labeling or by flow cytometry pro-duces different results. However, the significant corre-lation between corresponding parameters obtained with these techniques support the use of either method as "Intermediate biomarkers" of colorectal cancer risk and prognosis.