Diethylene glycol-induced toxicities show marked threshold dose response in rats.

Diethylene glycol (DEG) exposure poses risks to human health because of widespread industrial use and accidental exposures from contaminated products. To enhance the understanding of the mechanistic role of metabolites in DEG toxicity, this study used a dose response paradigm to determine a rat model that would best mimic DEG exposure in humans. Wistar and Fischer-344 (F-344) rats were treated by oral gavage with 0, 2, 5, or 10g/kg DEG and blood, kidney and liver tissues were collected at 48h. Both rat strains treated with 10g/kg DEG had equivalent degrees of metabolic acidosis, renal toxicity (increased BUN and creatinine and cortical necrosis) and liver toxicity (increased serum enzyme levels, centrilobular necrosis and severe glycogen depletion). There was no liver or kidney toxicity at the lower DEG doses (2 and 5g/kg) regardless of strain, demonstrating a steep threshold dose response. Kidney diglycolic acid (DGA), the presumed nephrotoxic metabolite of DEG, was markedly elevated in both rat strains administered 10g/kg DEG, but no DGA was present at 2 or 5g/kg, asserting its necessary role in DEG-induced toxicity. These results indicate that mechanistically in order to produce toxicity, metabolism to and significant target organ accumulation of DGA are required and that both strains would be useful for DEG risk assessments.

Association between human papilloma virus/Epstein-Barr virus coinfection and oral carcinogenesis.

BACKGROUND: The recent epidemic of head and neck squamous cell carcinomas associated with human papilloma virus (HPV) has not addressed its association with lymphoid tissue in the oropharynx or the potential role of Epstein-Barr virus (EBV)/HPV coinfection. METHODS: The prevalence of HPV and EBV infection/coinfection and CD21 mRNA expression were determined in normal and cancerous tissues from the oropharynx using in situ hybridization (ISH), p16, and quantitative reverse transcriptase PCR (qRT-PCR). The effects of coinfection on tumorigenicity were evaluated using proliferation and invasion assays. RESULTS: Normal oropharynx, tonsil, non-cancer base of tongue (BOT), and BOT from sleep apnea patients demonstrated EBV positivity ranging from 7% to 36% depending on the site and methods of detection used (qRT-PCR or ISH). Among non-malignant BOT samples, HPV positivity was noted only in 20%. The percent of tonsil and BOT cancers positive for HPV (up to 63% and 80%, respectively) or coinfected with HPV/EBV (up to 25% and 70%, respectively) were both significantly associated with cancer status. Notably, HPV/EBV coinfection was observed only in malignant tissue originating in lymphoid-rich oropharynx sites (tonsil, BOT). CD21 mRNA (the major EBV attachment receptor) was detected in tonsil and BOT epithelium, but not in soft-palate epithelium. Coinfected cell lines showed a significant increase in invasiveness (P < 0.01). CONCLUSIONS: There is a high prevalence of HPV/EBV infection and coinfection in BOT and tonsil cancers, possibly reflecting their origins in lymphoid-rich tissue. In vitro, cells modeling coinfection have an increased invasive potential.

Anti-lymphangiogenic properties of mTOR inhibitors in head and neck squamous cell carcinoma experimental models.

BACKGROUND: Tumor dissemination to cervical lymph nodes via lymphatics represents the first step in the metastasis of head and neck squamous cell carcinoma (HNSCC) and is the most significant predictor of tumor recurrence decreasing survival by 50%. The lymphatic suppressing properties of mTOR inhibitors are not yet well understood. METHODS: Lymphatic inhibiting effects of rapamycin were evaluated in vitro using two lymphatic endothelial cell (LEC) lines. An orthotopic mouse model of HNSCC (OSC-19 cells) was used to evaluate anti-lymphangiogenic effects of rapamycin in vivo. The incidence of cervical lymph node metastases, numbers of tumor-free lymphatic vessels and those invaded by tumor cells in mouse lingual tissue, and expression of pro-lymphangiogenic markers were assessed. RESULTS: Rapamycin significantly decreased lymphatic vascular density (p = 0.027), reduced the fraction of lymphatic vessels invaded by tumor cells in tongue tissue (p = 0.013) and decreased metastasis-positive lymph nodes (p = 0.04). Rapamycin also significantly attenuated the extent of metastatic tumor cell spread within lymph nodes (p < 0.0001). We found that rapamycin significantly reduced LEC proliferation and was correlated with decreased VEGFR-3 expression in both LEC, and in some HNSCC cell lines. CONCLUSIONS: The results of this study demonstrate anti-lymphangiogenic properties of mTOR inhibitors in HNSCC. mTOR inhibitors suppress autocrine and paracrine growth stimulation of tumor and lymphatic endothelial cells by impairing VEGF-C/VEGFR-3 axis and release of soluble VEGFR-2. In a murine HNSCC orthotopic model rapamycin significantly suppressed lymphovascular invasion, decreased cervical lymph node metastasis and delayed the spread of metastatic tumor cells within the lymph nodes.

Teenage cervical screening in a high risk American population.

BACKGROUND: The new 2009 ACOG guideline for cervical cytology screening changed the starting age to 21 years regardless of the age of onset of sexual intercourse. However, many recent studies have shown a dramatic increase in the incidence of cervical epithelial abnormalities among adolescents within the past two decades. MATERIALS AND METHODS: For this study, the reports of 156,342 cervical cytology were available of which 12,226 (7.8%) were from teenagers. A total of 192 teenagers with high grade intraepithelial lesion (HSIL) cervical cytology were identified. The ages ranged from 13 to 19 years with a mean of 17.7 years and a median of 18 years. Among them, 31.3% were pregnant, 12.0% were postpartum, and 13.5% were on oral contraceptive. Ninety-eight had prior cervical cytology. RESULTS: The teenagers had statistically significant higher detection rates of overall abnormal cervical cytology (23.6% vs. 6.6%, P = 0), with 15.4% vs. 3.2% (P = 0) of low grade intraepithelial lesion (LSIL) and 1.8% vs. 1.0% (P = 2.56 × 10(-13) ) of HSIL compared to women ≥20 years. The teenage group had the highest abnormal cytology among all age groups. The LSIL/HSIL ratio was 8.5:1 for teenagers and 3.1:1 for women ≥20 years. A total of 131 teenagers had cervical biopsies within 12 months of the HSIL cytology, with diagnoses of 39 CIN 3, 1 VAIN 3, 15 CIN 2, 62 CIN 1, and 14 had a negative histology (CIN 0). Only in 19 of these 39 women, the CIN 2/3 lesion proved to be persistent. CONCLUSION: We conclude that cytology screening of high risk teenagers is effective in detecting CIN 2/3 lesions. Moreover, treatment and careful follow-up can be realized.

Trimodal therapy for inflammatory breast cancer: a surgeon's perspective.

Inflammatory breast cancer (IBC) is a rare and most aggressive form of breast cancer. The onset and progression of disease are rapid; diagnosis must be made expediently to initiate treatment quickly. In this review, the clinical presentation, trimodal therapy, surgical principles and a brief summary of the Louisiana State University at Shreveport experience with IBC are presented. With this aggressive approach, 5-year survival of better than 40-50% can be expected. This represents a substantive improvement in clinical outcome for IBC patients compared with 30 years ago.

Fine needle aspiration of parapharyngeal space adult rhabdomyoma: a case report.

BACKGROUND: Rhabdomyomas are rare benign tumors of striated muscle and include cardiac and extracardiac types. Extracardiac rhabdomyomas are divided in three subtypes (adult, fetal, genital). The adult type is usually found in the head and neck regions of elderly persons. Misinterpretations in initial diagnosis of adult rhabdomyomas on fine needle aspiration have been reported. CASE: A 64-year-old man presented with gurgling and difficulty swallowing for approximately 3 months. Computed tomography and magnetic resonance imaging showed a 5.8-cm solid mass located in the right parapharyngeal space. Fine needle aspiration smears were cellular, showing cohesive clusters of cells with scattered individual cells. Cells had abundant eosinophilic glassy cytoplasm, peripherally placed round nuclei, and prominent nucleoli. Many traversing vessels were noted, but cross-striations were not seen. The cell block demonstrated clusters of cells with abundant eosinophilic granular cytoplasm, some with clear and/or vacuolated cytoplasm, and possible cross-striations. Tumor cells were positive for desmin. The lesion closely resembled normal muscle tissue. Electron microscopy showed many cells containing actin and myosin filaments with Z-band material. CONCLUSION: Correct diagnosis can be achieved with a combination of awareness of the lesion, familiarity with the characteristic cytologic features, and application of appropriate immunohistochemistry markers. Classic electron microscopic findings can support the diagnosis.

The role of routine immunohistochemistry for Helicobacter pylori in gastric biopsy.

Helicobacter pylori infection is associated with gastritis, gastric ulcer, gastric adenocarcinoma, and mucosal associated lymphoid tissue lymphoma. Documenting the presence of H pylori in a gastric biopsy is essential for appropriate patient care. Several special stains and immunohistochemistry (IHC) stain for H pylori are available, and many laboratories are routinely using one of them. We introduced routine IHC for H pylori about a year ago, and this study aims to investigate the value of this protocol. A total of 224 patients qualified for the study criteria during this period. The diagnoses were chronic active gastritis (68), chronic gastritis (76), no pathologic abnormality (50), reactive gastropathy (24), and polyps (6). Fifty-four cases were positive for H pylori on IHC, including 50 chronic active gastritis and 4 chronic gastritis. The IHC positive rate was 73.5% (50/68) in chronic active gastritis, 5.3% (4/76) in chronic gastritis, and 0% (0/80) in other diagnoses. The sensitivity/specificity of finding H pylori by blindly reviewing hematoxylin and eosin slides was 100%/100%, 100%/100%, 95%/100%, and 100%/100% from the 4 authors. Our results showed that many gastric biopsies (35.7%, 80/224) had no pathologic abnormality or reactive gastropathy and did not need a routine IHC for H pylori. Hematoxylin and eosin slide review had a very good sensitivity and specificity with all levels of observers. In summary, IHC for H pylori should not be routinely used, especially during these economically challenging times. Immunohistochemistry should be reserved for unexplained gastritis and previously treated patients with likely low organism density.

Elevated chemokine receptor CXCR4 expression in primary tumors following neoadjuvant chemotherapy predicts poor outcomes for patients with locally advanced breast cancer (LABC).

Purpose Patients with locally advanced breast cancer (LABC) have a poor outcome. A molecular predictor to identify at-risk patients is sorely needed. CXCR4 is a chemokine receptor that has been linked to breast cancer invasion and metastasis. We postulate that in patients with LABC, CXCR4 overexpression levels in cancer specimens following neoadjuvant chemotherapy predict cancer outcome. Experimental design 54 patients with LABC were prospectively accrued and analyzed. All had neoadjuvant chemotherapy and definitive surgical therapy. Study homogeneity was maintained by standardized treatment, surveillance, and compliance protocols. A 1 cm(3) cancer from the surgical specimens of each patient was retrieved for analysis. CXCR4 levels were detected using Western blots, and results were quantified against 1 mug of protein from HeLa cells. CXCR4 expression was defined as low (<6.6-fold) or high (> or =6.6-fold). Primary endpoints were cancer recurrence and death. Statistical analysis performed included independent samples t-test, chi-square test, Spearman Rank analysis, Kaplan-Meier survival analysis, log-rank test, and Cox proportional hazard model. Results With a median follow-up of 30 months, patients with high CXCR4 overexpression (> or =6.6-fold) had a significantly higher incidence of recurrence (P = 0.0006) and cancer death (P = 0.0128) than those with low CXCR4 overexpression (<6.6-fold). The relative risks for recurrence and death in the high CXCR4 group were 27.3-fold (95% CI: 6.2-120.8; P = 0.001) and 4.8-fold (95% CI: 1.5-15.0; P = 0.0076) higher, respectively than those in the low CXCR4 group. Conclusion High CXCR4 overexpression in specimens from LABC patients receiving neoadjuvant chemotherapy was predictive of cancer outcome.

Papillary oncocytic cystadenoma of the parotid glands: a report of 2 cases with varied cytologic features.

BACKGROUND: Papillary cystadenoma is a rare salivary gland neoplasm, and oncocytic change can be focal or marked. Papillary oncocytic cystadenoma has been reported mainly in the minor salivary glands and occasionally in the parotid glands. The cytologic features vary. CASES: A 26-year-old female presented with a 2.4-cm, cystic right parotid gland mass present for 4 months. Fine needle aspiration (FNA) showed cellular smears with sheets of oncocytic cells and some with micropapillary architecture. The diagnosis ofa neoplasm was rendered and excisional biopsy recommended. Oncocytic neoplasm was diagnosed during intraoperative consultation, and final surgical histology showed a unilocular, cystic, oncocytic neoplasm with variable papillary projections. A 52-year-old male presented with a 1.5-cm, cystic left parotid mass enlarging for the past few months. FNA showed less cellular smears with extensive necrotic debris and a few large sheets of epithelial cells with vague papillary architecture. Oncocytic neoplasm was diagnosed during intraoperative consultation, and final surgical histology showed a unilocular cystic lesion with multiple papillary fronds lined with oncocytic cells and focal metaplastic squamous cells. CONCLUSION: Papillary cystadenoma is rare in the parotid glands, and cytologic features may vary. Warthin's tumor, oncocytoma, intraductal papilloma and acinic cell carcinoma may arise in the differential diagnosis. In cases with extensive necrotic debris and metaplastic squamous cells, branchial cyst and cystic metastatic squamous carcinoma may also need to be considered.

Fine needle aspiration of salivary glands: 5-year experience from a single academic center.

OBJECTIVE: To investigate 5 years' experience with fine needle aspiration (FNA) of salivary glands at a single academic center. STUDY DESIGN: A total of 191 salivary gland FNAs were performed at Louisiana State University Health Science Center from 2003 to 2007, and all were done on major salivary glands except for 1 case. RESULTS: The cytologic diagnoses included 17 malignancies, 6 atypia, 73 neoplasms, 87 negative and 18 nondiagnostic. Eighty-six cases had histologic follow-up (45.0%). There were 5 false negatives: 2 adenoid cystic carcinomas, 1 acinic cell carcinoma, 1 polymorphous low grade adenocarcinoma and 1 metastatic basaloid squamous cell carcinoma. The only false positive was a pleomorphic adenoma misdiagnosed as adenoid cystic carcinoma. Four reactive processes were diagnosed as benign neoplasms, including 2 granulomatous inflammation and 2 chronic sialadenitis. Five benign neoplasms were interpreted as reactive processes, including 2 Warthin's tumors, 2 sebaceous lymphoadenomas and 1 pleomorphic adenoma. The overall accuracy in distinguishing benign from malignant lesions was 79.1%, and the sensitivity for salivary neoplasia was 89.4%. CONCLUSION: Our results are consistent with the literature that salivary gland FNA has good sensitivity, specificity and accuracy in the diagnosis of salivary neoplasms. FNA can play a significant role in triaging patients with onsite cytologic interpretation and can reduce many unnecessary surgeries.

A prospective trial on initiation factor 4E (eIF4E) overexpression and cancer recurrence in node-negative breast cancer.

BACKGROUND: Eukaryotic Initiation Factor 4E (eIF4E) plays a crucial role in translation control. High eIF4E increase in tumor specimens independently predicted recurrence by multivariate analysis. This prospective trial of node-negative only breast cancer patients was initiated to test the hypothesis that high eIF4E increase predicts cancer recurrence and death, independent of nodal status. METHODS: The trial was powered to detect a 2.4-fold increase in relative risk for cancer recurrence in 240 node-negative patients on the basis of high versus low eIF4E increase in tumor specimens (type I error = .05, statistical power = .08). eIF4E level was quantified by using Western blot test. Treatment and surveillance regimens were standardized. Primary endpoints were cancer recurrence and cancer-related death. RESULTS: Of the 242 patients accrued, 112 were in the low eIF4E group (<7.5-fold), 82 were in the intermediate eIF4E group (7.5- to 15-fold), and 48 were in the high eIF4E group (>15-fold). Patients in the high eIF4E group had a statistically significant higher rate of cancer recurrence and cancer-related death (P = .0001 and P < or = .0001, log rank test). The relative risk for cancer recurrence was 2.2-fold higher in the high eIF4E group (P = .001, Cox model), and 3.7-fold higher for cancer-related death (P = .0009). CONCLUSIONS: In node-negative breast cancer, high eIF4E increase predicted a higher rate of cancer recurrence and death. High eIF4E patients had a >2-fold increase in relative risk for cancer recurrence and nearly a 4-fold increase in relative risk for death. This supports our hypothesis that high eIF4E is an independent predictor for breast cancer outcome independent of nodal status.

Local and systemic Curcumin C3 complex inhibits 4NQO-induced oral tumorigenesis via modulating FGF-2/FGFR-2 activation.

Head and Neck Squamous cell carcinoma (HNSCC) can be characterized by synchronous tumors in the upper aerodigestive tract. Second primary tumors as a result of field cancerization are a significant problem amongst patients with risk factors for HNSCC, indicating a need for chemo preventive agents. We investigated the efficacy of local and systemic Curcumin C3 complex (C3); a purified mixture of Curcumin, bisdemethoxy Curcumin and demethoxy Curcumin as a chemo preventative agent in 4-nitroquinoline-1-oxide (4NQO)-induced tumorigenesis in mice. The effect of local C3 application was compared to C3 administered orally and in combination with systemic administration. C57Bl/6 mice were administered 4NQO (50 µg/ml) in the drinking water for 16 weeks. At 12 weeks, mice were subjected to daily treatment with either vehicle (control), or 15 mg C3 complex by local delivery, gavage, or combined local and gavage for 28 days (16 week time point), and followed up to 22 weeks. Compared to local and oral systemic C3 administration, combination of local and systemic application significantly decreased multiplicity of 4NQO-induced preneoplastic and neoplastic lesions (p<0.05). Treatment with C3 correlated with a decrease in cell proliferation compared to the 4NQO group. Further, pre-treatment with C3 complex significantly attenuated 4NQO induced expression of basic fibroblast growth factor (FGF-2) and its cognate receptor FGFR-2, suggesting an important role of FGF-2/FGFR-2 axis in chemoprevention of HNSCC (p<0.05). Our findings suggest that a combination of local and systemic C3 complex could effectively target proliferation and inhibit 4NQO-induced tumorigenesis via modulation of the FGF-2/FGFR-2 axis as a mechanism for its efficacy.

Correlation of TLK1B in elevation and recurrence in doxorubicin-treated breast cancer patients with high eIF4E overexpression.

BACKGROUND: Tousled-like kinase 1B (TLK1B), a mammalian threonine kinase, facilitates the repair of DNA breaks. Eukaryotic initiation factor 4E (eIF4E) overexpression leads to the upregulation of TLK1B. Doxorubicin, commonly used in the adjuvant setting for breast cancer, causes DNA breaks. We hypothesized that the degree of TLK1B elevation is correlated with eIF4E overexpression and translates clinically to an increased risk for recurrence in breast cancer patients treated with doxorubicin-based adjuvant chemotherapy. STUDY DESIGN: We prospectively accrued 152 patients with stage I to III breast cancer treated with a doxorubicin-based chemotherapy in an adjuvant setting. Standardized treatment and surveillance protocols were used. eIF4E and TLK1B protein levels were quantified using Western blots, and patients were divided into tertiles based on previously reported stratification of eIF4E and TLK1B levels. Primary end points were cancer recurrence and death. Statistical analysis included Spearman's correlation, Kaplan-Meier survival analysis, log rank test, and the Cox proportional hazard model. RESULTS: The degree of TLK1B overexpression was highly correlated with the degree of eIF4E elevation (r=0.25, p=0.0025, Spearman rank correlation). Patients whose tumors were in the highest tertile for eIF4E overexpression had a higher risk for cancer recurrence and cancer death (p=0.015 and 0.049, respectively, log rank test). After adjusting for T-stage, nodal status, age, and estrogen receptor and progesterone receptor status, patients with tumors in the highest tertile of TLK1B overexpression treated with doxorubicin were 1.7-fold more likely to suffer recurrence than those in the low TLK1B group treated similarly (p=0.0078, CI, 1.17 to 2.75, Cox model). CONCLUSIONS: TLK1B overexpression was highly correlated with the level of eIF4E elevation. High TLK1B in cancer specimens was associated with a higher risk for cancer recurrence in patients treated with doxorubicin-based adjuvant chemotherapy.

Sildenafil Transiently Delays Early Alveolar Healing of Tooth Extraction Sockets.

Bone is a unique tissue that has the ability to repair itself and return to full function. Bone regeneration is a well synchronized biological process that recapitulates embryonic bone development. The establishment of a functional vascular supply has been shown to be essential for proper ossification of newly deposited bone, and impaired angiogenesis as in advanced age, diabetes, and anti-cancer treatments affect bone repair. Endothelial Guanosine, 3', 5'-Cyclic Monophophate(cGMP) is known to support angiogenesis, and sildenafil, a Phosphodiesterase 5 (PDE5) antagonist, prevents cGMP hydrolysis and thereby, promotes the formation of new blood vessels. Since the development of functional vascular networks is critical to bone repair, we investigated the effects of sildenafil on early alveolar bone regeneration following exodontia. Our results demonstrate that per-oral administration of sildenafil (10 mg/kg/day) in rats delays the dissolution and replacement of the sanguine clot with granulation tissue. As a result, the number of replicating cells, a hallmark of regenerating tissue, observed on day 4 was remarkably lower in sildenafil-treated animals than their control counterparts (mean±SD; control: 47.35±9.21; sildenafil: 11.47±5.14). Similarly, cells expressing transcription factor Cbfa-1/Runx2 and osteopontin, markers of differentiating osteoblasts, were fewer in treated animals (mean±SD; control: 83.18 ± 4.60; sildenafil: 13.77 ± 4.63). Treatment with hydrolysis-resistant cyclic GMP (cGMP) showed findings similar to sildenafil-treated animals suggesting a negative impact of cGMP on early inflammatory phase of bone healing. However, histological differences were not significant between the 2 groups on day 8. Based on these findings, we conclude that sildenafil temporarily retards early events in alveolar bone healing.

In-vivo evidence of nephrotoxicity and altered hepatic function in rats following administration of diglycolic acid, a metabolite of diethylene glycol.

CONTEXT: Diglycolic acid (DGA) is one of the two primary metabolites of diethylene glycol (DEG). DEG is an industrial solvent that has been implicated in mass poisonings resulting from product misuse in the United States and worldwide, with the hallmark toxicity being acute kidney injury, hepatotoxicity, encephalopathy and peripheral neuropathy. Our laboratory has generated in-vitro evidence suggesting that DGA is the metabolite responsible for the proximal tubule necrosis and decreased kidney function observed following DEG ingestion. Furthermore, we have shown that DGA specifically accumulates in kidney tissues (100× higher than peak blood concentrations) following DEG administration. OBJECTIVE: To examine renal and hepatic accumulation and dysfunction following direct administration of DGA in-vivo. We hypothesize that administration of DGA will result in renal and hepatic DGA accumulation, as well as proximal tubular necrosis and liver injury. MATERIALS AND METHODS: Adult male Wistar rats were divided into three groups dosed with 0, 100 or 300 mg/kg DGA via single oral gavage. Urine was collected every 6-12 h and blood, kidneys and liver were removed upon sacrifice at 48 h post-dosing for analysis. RESULTS: DGA accumulated significantly in both kidney and liver tissue only at 300 mg DGA/kg. DGA concentrations in the kidneys and liver correlated with renal and hepatic injury, respectively. Histopathological and clinical chemistry analysis revealed that DGA-treated animals exhibited moderate liver fatty accumulation and marked renal injury, again only at 300 mg/kg. DISCUSSION: DGA-induced kidney injury demonstrated a steep dose response threshold, where severe damage occurred only in animals given 300 mg/kg DGA, while no toxicity was observed at 100 mg/kg. CONCLUSION: These results provide evidence for in-vivo toxicity following direct administration of DGA, a metabolite of DEG. The steep dose-response threshold for toxicity suggests mechanistically that there is likely a saturable step that results in DGA accumulation in target organs.

Cystatin m: a novel candidate tumor suppressor gene for breast cancer.

The contribution of pericellular proteolysis to tumor progression is well documented. To better understand protease biology and facilitate clinical translation, specific proteolytic systems need to be better defined. In particular, the precise role of endogenous protease inhibitors still needs to be deciphered. We reported previously that cystatin M, a potent endogenous inhibitor of lysosomal cysteine proteases, significantly suppressed in vitro cell proliferation, migration, and Matrigel invasion. Here, we show that scid mice orthotopically implanted with breast cancer cells expressing cystatin M show significantly delayed primary tumor growth and lower metastatic burden in the lungs and liver when compared with mice implanted with mock controls. The incidence of metastasis, however, appeared to be unaltered between the cystatin M group and the control group. Experimental metastasis assays suggest that cystatin M suppressed tumor cell proliferation at the secondary site. By using laser capture microdissection and quantitative reverse transcription-polymerase chain reaction, we found consistent expression of cystatin M in normal human breast epithelial cells, whereas expression was decreased by 86% in invasive ductal carcinoma (IDC) cells of stage I to IV patients. Complete loss of expression of cystatin M was observed in two of three IDCs from stage IV patients. Immunohistochemical studies confirmed that expression of cystatin M in IDCs was partially or completely lost. We propose cystatin M as a novel candidate tumor suppressor gene for breast cancer.

DNA damage response and repair data with pharmacological modulators of Tousled.

Human Tousled kinase 1 (TLK1) plays an important role in chromatin remodeling, replication, and DNA damage response and repair. TLK1 activity is immediately, but transiently, downregulated after genotoxic insult, and its recovery is important for exit from checkpoint arrest and cell survival after radiation. The data in this article compliments research presented in the paper titled, "Tousled kinase activator, gallic acid, promotes DNA repair and suppresses radiation cytotoxicity in salivary gland cells" [1]. The identification of small molecule activators and inhibitors of TLK1 provided an opportunity to pharmacologically alter the protein׳s activity to elucidate its role in DNA damage response pathways. TLK1 effectors, gallic acid (GA) and thioridazine (THD) activate and inhibit the kinase, respectively, and the data report on the impact of these compounds and the significance of TLK1 to DNA break repair and the survival of human salivary acinar cells.

Tousled kinase activator, gallic acid, promotes homologous recombinational repair and suppresses radiation cytotoxicity in salivary gland cells.

Accidental or medical radiation exposure of the salivary glands can gravely impact oral health. Previous studies have shown the importance of Tousled-like kinase 1 (TLK1) and its alternate start variant TLK1B in cell survival against genotoxic stresses. Through a high-throughput library screening of natural compounds, the phenolic phytochemical, gallic acid (GA), was identified as a modulator of TLK1/1B. This small molecule possesses anti-oxidant and free radical scavenging properties, but in this study, we report that in vitro it promotes survival of human salivary acinar cells, NS-SV-AC, through repair of ionizing radiation damage. Irradiated cells treated with GA show improved clonogenic survival compared to untreated controls. And, analyses of DNA repair kinetics by alkaline single-cell gel electrophoresis and γ-H2AX foci immunofluorescence indicate rapid resolution of DNA breaks in drug-treated cells. Study of DR-GFP transgene repair indicates GA facilitates homologous recombinational repair to establish a functional GFP gene. In contrast, inactivation of TLK1 or its shRNA knockdown suppressed resolution of radiation-induced DNA tails in NS-SV-AC, and homology directed repair in DR-GFP cells. Consistent with our results in culture, animals treated with GA after exposure to fractionated radiation showed better preservation of salivary function compared to saline-treated animals. Our results suggest that GA-mediated transient modulation of TLK1 activity promotes DNA repair and suppresses radiation cytoxicity in salivary gland cells.

Biomarker and Pathologic Predictors of Cutaneous Squamous Cell Carcinoma Aggressiveness.

OBJECTIVE: Aggressive cutaneous squamous cell carcinoma (cSCC) patients are at increased risk of metastasis. Currently, there are no accepted criteria or biomarkers for reliably predicting individuals at risk for recurrence and metastasis. Our objective is to determine if pS6 and pERK can predict cSCC aggressiveness and to identify primary tumor characteristics that may predict parotid metastasis. STUDY DESIGN: Retrospective case series. SETTINGS: Tertiary care center. SUBJECTS AND METHODS: An Institutional Review Board-approved retrospective review was performed for patients with facial cSCC, with and without metastasis to the parotids. Subjects for the study were identified through the Louisiana Tumor Registry, Veterans Medical Records, and LSU Health-Shreveport pathology database. Tumor specimens from patients with cSCC and cSCC with parotid metastasis were analyzed for pERK and pS6 expression through immunohistochemistry. To identify risk factors for tumor aggressiveness, multiple logistic regression analysis was used to evaluate patients with cSCC that was metastatic to the parotid and managed surgically. RESULTS: cSCC with parotid metastasis specimens exhibited significantly higher average pS6 but not pERK positivity than those from cSCC without metastasis (P < .05). Primary lesion-positive margins (P < .01), size of the skin tumor (P < .01) and degree of tumor differentiation (P < .01) were significantly associated with parotid metastasis. CONCLUSION: Surgical history of cSCC, primary lesion-positive margins, degree of differentiation, and lesion size together with pS6 positivity appear to be predictors of cSCC aggressiveness and should prompt increased monitoring or elective parotidectomy.

Photopreventive Effect and Mechanism of AZD4547 and Curcumin C3 Complex on UVB-Induced Epidermal Hyperplasia.

Aggressive cutaneous squamous cell carcinoma (cSCC) of the skin is the second most common type of skin cancer in the United States due to high exposure to ultraviolet B (UVB) radiation. In our previous studies, Curcumin C3 complex (C3), a standardized preparation of three curcumonoids, delayed UVB-induced tumor incidence and inhibited multiplicity. Exposure to UVB activates mTOR and FGFR signaling that play a key role in skin tumorigenesis. The purpose of this study was to investigate the efficacy of C3 complex to afford protection against acute UVB-induced hyperproliferation by targeting the mTOR and FGFR signaling pathways. Pretreatment with C3 complex significantly inhibited UVB-induced FGF-2 induction, FGF-2-induced cell proliferation, progression and colony formation, mTORC1 and mTORC2 activation, and FGFR2 phosphorylation in the promotion-sensitive JB6 cells epithelial cells. Further, FGFR was critical for UVB-induced mTOR activation, suggesting an important role of FGFR2 in UVB-induced mTOR signaling. SKH-1 mice pretreated with C3 (15 mg/kg/b.w.) for 2 weeks followed by a single exposure to UVB (180 mj/cm(2)) significantly attenuated UVB-induced mTORC1, mTORC2, and FGFR2 activation. To further assess the role of FGFR in UVB-induced hyperproliferation, SKH-1 mice were pretreated with AZD4547 (5 mg/kg/b.w.); a selective pan-FGFR kinase inhibitor followed by single exposure to UVB (180 mj/cm(2)). AZD4547 significantly inhibited UVB-induced mTORC1 and mTORC2 activation, epidermal hyperplasia and hyperproliferation. Our studies underscore the importance of FGFR signaling in UVB-induced acute skin changes and the role of FGFR/mTOR signaling in mediating the effects of C3 complex in the pathogenesis of skin cancer.