Comparison of the prognosis of bisphosphonate-related osteonecrosis of the jaw caused by oral and intravenous bisphosphonates

Bisphosphonates (BPs) have been used in medical practice for the treatment of osteoporosis, bone metastasis, and multiple myeloma. Although many studies have been published, the treatment and prognosis of bisphosphonate-related osteonecrosis of the jaw (BRONJ) remain unclear. This study included 59 patients with BRONJ: 29 had taken oral BPs and 30 had taken intravenous (IV) BPs. All received conservative treatments. When separated sequestra were seen, a sequestrectomy was performed. Segmental mandibular resection was performed when pathological fractures were diagnosed. The outcomes of treatments were compared between groups. For patients treated with oral rinses or mandibular resection, the number in whom clinical healing was observed did not differ between the oral BP and IV BP groups. With regard to sequestrectomy, 94% of patients in the oral BP group showed improvement with this treatment compared to 50% in the IV BP group. The number of patients in whom clinical healing of BRONJ was achieved was statistically better in the oral BP group than in the IV BP group after 6 months of treatment (P<0.001). The results showed that >90% of patients treated with oral BPs could be cured. However, 50% of patients treated with IV BPs did not show an improvement. Additional research is needed to further increase the therapeutic efficacy for the resolution of BRONJ.

Effect of interleukin-1beta and dehydroepiandrosterone on the expression of lumican and fibromodulin in fibroblast-like synovial cells of the human temporomandibular joint

Several epidemiological studies have reported that temporomandibular disorders (TMDs) are more prevalent in women than in men. It has recently been proposed that sex hormones such as estrogen, testosterone and dehydroepiandrosterone (DHEA) are involved with the pathogenesis of TMDs. Although studies have investigated the relationship between estrogen and testosterone and the restoration of TMDs, the relationship between DHEA and TMDs is unknown. The synovial tissue of the temporomandibular joint (TMJ) is made up of connective tissue with an extracellular matrix (ECM) composed of collagen and proteoglycan. One proteoglycan family, comprised of small leucine-rich repeat proteoglycans (SLRPs), was found to be involved in collagen fibril formation and interaction. In recent years, the participation of SLRPs such as lumican and fibromodulin in the internal derangement of TMJ has been suggested. Although these SLRPs may contribute to the restoration of the synovium, their effect is still unclear. The purpose of this study was to investigate the effect of DHEA, a sex hormone, on the expression of lumican and fibromodulin in human temporomandibular specimens and in cultured human TMJ fibroblast-like synovial cells in the presence or absence of the pro-inflammatory cytokine interleukin-1beta (IL-1beta). In the in vivo study, both normal and osteoarthritic (OA) human temporomandibular synovial tissues were immunohistochemically examined. In the in vitro study, five fibroblast-like synoviocyte (FLS) cell lines were established from human TMJ synovial tissue of patients with osteoarthritis. The subcultured cells were then incubated for 3, 6, 12 or 24 h with/without IL-1beta (1 ng/mL) in the presence or absence of DHEA (10 μM). The gene expression of lumican and fibromodulin was examined using the real-time polymerase chain reaction (PCR) and their protein expression was examined using immunofluorescent staining. We demonstrated that the expression of lumican differs from that of fibromodulin in synovial tissue and furthermore, that IL-1beta induced a significant increase in lumican mRNA and immunofluorescent staining in FLS compared to cells without IL-1beta. DHEA plus IL-1beta induced a significant increase in fibromodulin, but not in lumican mRNA, compared to DHEA alone, IL-1beta alone and in the absence of DHEA and IL-1beta. In immunofluorescent staining, weaker fibromodulin staining of FLS cells was observed in cells cultured in the absence of both DHEA and IL-1beta compared to fibromodulin staining of cells cultured with DHEA alone, with DHEA plus IL-1beta, or with IL-1beta alone. These results indicate that DHEA may have a protective effect on synovial tissue in TMJ by enhancing fibromodulin formation after IL-1beta induced inflammation. DHEA enhancement of fibromodulin expression may also exert a protective effect against the hyperplasia of fibrous tissue that TGF-beta1 induces. In addition lumican and fibromodulin are differentially expressed under different cell stimulation conditions and lumican and fibromodulin may promote regeneration of the TMJ after degeneration and deformation induced by IL-1beta.

Evidence for TRPA1 involvement in central neural mechanisms in a rat model of dry eye

Dry eye (DE) disease is commonly associated with ocular surface inflammation, an unstable tear film and symptoms of irritation. However, little is known about the role of central neural mechanisms in DE. This study used a model for persistent aqueous tear deficiency, exorbital gland removal, to assess the effects of mustard oil (MO), a transient receptor potential ankyrin (TRPA1) agonist, on eyeblink and eyewipe behavior and Fos-like immunoreactivity (Fos-LI) in the trigeminal brainstem of male rats. Spontaneous tear secretion was reduced by about 50% and spontaneous eyeblinks were increased more than 100% in DE rats compared to sham rats. MO (0.02-0.2%) caused dose-related increases in eyeblink and forelimb eyewipe behavior in DE and sham rats. Exorbital gland removal alone was sufficient to increase Fos-LI at the ventrolateral pole of trigeminal interpolaris/caudalis (Vi/Vc) transition region, but not at more caudal regions of the trigeminal brainstem. Under barbiturate anesthesia ocular surface application of MO (2-20%) produced Fos-LI in the Vi/Vc transition, in the mid-portions of Vc and in the trigeminal caudalis/upper cervical spinal cord (Vc/C1) region that was significantly greater in DE rats than in sham controls. MO caused an increase in Fos-LI ipsilaterally in superficial laminae at the mid-Vc and Vc/C1 regions in a dose-dependent manner. Smaller, but significant, increases in Fos-LI also were seen in the contralateral Vc/C1 region in DE rats. TRPA1 protein levels in trigeminal ganglia from DE rats ipsilateral and contralateral to gland removal were similar. Persistent tear reduction enhanced the behavioral and trigeminal brainstem neural responses to ocular surface stimulation by MO. These results suggested that TRPA1 mechanisms play a significant role in the sensitization of ocular-responsive trigeminal brainstem neurons in this model for tear deficient DE.

MicroRNA-574-3p, identified by microRNA library-based functional screening, modulates tamoxifen response in breast cancer

Most primary breast cancers express estrogen receptor α and can be treated via endocrine therapy using anti-estrogens such as tamoxifen; however, acquired endocrine resistance is a critical issue. To identify tamoxifen response-related microRNAs (miRNAs) in breast cancer, MCF-7 cells infected with a lentiviral miRNA library were treated with 4-hydroxytamoxifen (OHT) or vehicle for 4 weeks, and the amounts of individual miRNA precursors that had integrated into the genome were evaluated by microarray. Compared to the vehicle-treated cells, 5 'dropout' miRNAs, which were downregulated in OHT-treated cells, and 6 'retained' miRNAs, which were upregulated in OHT-treated cells, were identified. Of the dropout miRNAs, we found that miR-574-3p expression was downregulated in clinical breast cancer tissues as compared with their paired adjacent tissues. In addition, anti-miR-574-3p reversed tamoxifen-mediated suppression of MCF-7 cell growth. Clathrin heavy chain (CLTC) was identified as a miR-574-3p target gene by in silico algorithms and luciferase reporter assay using the 3' untranslated region of CLTC mRNA. Interestingly, loss and gain of miR-574-3p function in MCF-7 cells causes CLTC to be upregulated and downregulated, respectively. These results suggest that functional screening mediated by miRNA libraries can provide new insights into the genes essential for tamoxifen response in breast cancer.

Hand-assisted laparoscopic transhiatal esophagectomy with a systematic procedure for en bloc infracarinal lymph node dissection

Laparoscopic transhiatal esophagectomy is a minimally invasive approach for esophageal cancer. However, a transhiatal procedure has not yet been established for en bloc mediastinal dissection. The purpose of this study was to present our novel procedure, hand-assisted laparoscopic transhiatal esophagectomy, with a systematic procedure for en bloc mediastinal dissection. The perioperative outcomes of patients who underwent this procedure were retrospectively analyzed. Transhiatal subtotal mobilization of the thoracic esophagus with en bloc lymph node dissection distally from the carina was performed according to a standardized procedure using a hand-assisted laparoscopic technique, in which the operator used a long sealing device under appropriate expansion of the operative field by hand assistance and long retractors. The thoracoscopic procedure was performed for upper mediastinal dissection following esophageal resection and retrosternal stomach roll reconstruction, and was avoided based on the nodal status and operative risk. A total of 57 patients underwent surgery between January 2012 and June 2013, and the transthoracic procedure was performed on 34 of these patients. In groups with and without the transthoracic procedure, total operation times were 370 and 216 minutes, blood losses were 238 and 139 mL, and the numbers of retrieved nodes were 39 and 24, respectively. R0 resection rates were similar between the groups. The incidence of recurrent laryngeal nerve palsy was significantly higher in the group with the transthoracic procedure, whereas no significant differences were observed in that of pneumonia between these groups. The hand-assisted laparoscopic transhiatal method, which is characterized by a systematic procedure for en bloc mediastinal dissection supported by hand and long device use, was safe and feasible for minimally invasive esophagectomy.

Inhibition of fibrous adhesion formation in the temporomandibular joint of tenascin-C knockout mice

Tenascin-C (TNC) is a large hexameric extracellular matrix glycoprotein that is expressed in developing organs and tumors. It has been reported that TNC is expressed in inflamed synovial membranes and deformed discs of temporomandibular joint (TMJ) disorder. However, the role of TNC in TMJ is not fully known. In this study, the role of TNC in fibrous adhesion formation of TMJ was examined using TNC knockout (TNCKO) mice. Hypermobility was produced by excessive mouth opening method on the TMJ of both wild-type (WT) and TNCKO mice. TMJ wound healing was compared histologically, and the expression of TNC, fibronectin (FN) and α-smooth muscle actin (α-SMA) in the wounded TMJ was examined by immunohistochemical and immunoblot analyses. Based on histologic analysis, fibrous adhesions were observed in the TMJ of both TNCKO and wild-type (WT) mice after excessive mouth opening. However, fibrous adhesion formation in TNCKO mice occurred later than in WT mice. TNC was expressed in the wounded TMJ disc and mandibular fossa. Although FN and α-SMA expression in the TMJ of TNCKO and WT mice was up-regulated after excessive mouth opening, FN and α-SMA protein levels were higher in WT mice at the same time points. In the wounded TMJ, TNC appears to enhance the expression of FN and α-SMA, and a lack of TNC may reduce fibrous adhesion formation in the TMJ. TNC plays an important role in TMJ wound healing, especially for wounds generated by mechanical stress.

Overexpression of SMYD2 contributes to malignant outcome in gastric cancer

BACKGROUND

SET and MYND domain-containing protein 2 (SMYD2) is a lysine methyltransferase for histone H3, p53 and Rb and inhibits their transactivation activities. In this study, we tested whether SMYD2 (1q42) acts as a cancer-promoting factor by being overexpressed in gastric cancer.

METHODS

We analysed 7 gastric cancer cell lines and 147 primary tumor samples of gastric cancer, which were curatively resected in our hospital.

RESULTS

SET and MYND domain-containing protein 2 was detected in these cell lines (five out of seven cell lines; 71.4%) and primary tumor samples (fifty-six out of one hundred and forty-seven cases; 38.1%). Knockdown of SMYD2 using specific small interfering RNA inhibited proliferation, migration and invasion of SMYD2-overexpressing cells in a TP53 mutation-independent manner. Overexpression of SMYD2 protein correlated with larger tumor size, more aggressive lymphatic invasion, deeper tumor invasion and higher rates of lymph node metastasis and recurrence. Patients with SMYD2-overexpressing tumours had a worse overall rate of survival than those with non-expressing tumours (P=0.0073, log-rank test) in an intensity and proportion score-dependent manner. Moreover, multivariate analysis demonstrated that SMYD2 was independently associated with worse outcome (P=0.0021, hazard ratio 4.25 (1.69-10.7)).

CONCLUSIONS

These findings suggest that SMYD2 has a crucial role in tumor cell proliferation by its overexpression and highlight its usefulness as a prognostic factor and potential therapeutic target in gastric cancer.

Development of novel treatment with a bioabsorbable esophageal patch for benign esophageal stricture

Using a large animal model, we examined whether circumferential stricture after esophageal endoscopic submucosal dissection (ESD) can be treated by grafting a bioabsorbable esophageal patch. Circumferential ESD was performed on the thoracic esophagus in pigs (n = 6) to create a stricture, for which one of the following interventions was performed: (1) the stricture site was longitudinally incised, and an artificial esophageal wall (AEW) was grafted after placing a bioabsorbable stent (AEW patch group, n = 3); (2) endoscopic balloon dilation (EBD) was performed every other week after stricture development (EBD group, n = 3). In both groups, esophageal fluoroscopy was performed 8 weeks after the interventions, and the esophagus was excised for histological examination of the patched site. In the AEW patch group, esophageal fluoroscopy revealed favorable passage through the patched site. Histologically, the mucosal epithelium and lamina propria had regenerated as in the normal area. In the EBD group, the circumferential stricture site showed marked thickening, and there were hypertrophic scars associated with epithelial defects on the luminal surface. Histologically, defects of the mucosal epithelium and full-thickness proliferation of connective tissue were observed. AEW patch grafting was suggested to be a potentially novel treatment strategy for post-ESD esophageal circumferential stricture.

The antimicrobial protein S100A7/psoriasin enhances the expression of keratinocyte differentiation markers and strengthens the skin's tight junction barrier

BACKGROUND

S100A7/psoriasin is a member of the S100 protein family and is encoded in the epidermal differentiation complex, which contains genes for markers of epidermal differentiation. S100A7/psoriasin is overexpressed in hyperproliferative skin diseases, where it is believed not only to exhibit antimicrobial functions, but also to induce immunomodulatory activities, including chemotaxis and cytokine/chemokine production.

OBJECTIVES

To evaluate the effect of S100A7/psoriasin on keratinocyte differentiation and regulation of the tight junction (TJ) barrier.

METHODS

Expression of differentiation markers and TJ proteins in human keratinocytes was determined by real-time polymerase chain reaction and Western blot. The changes in TJ barrier function were assessed by transepithelial electrical resistance and paracellular permeability assays. Glycogen synthase kinase-3 (GSK-3) and mitogen-activated protein kinase (MAPK) activation was analysed by Western blot, whereas β-catenin and E-cadherin activation was evaluated by Western blot and immunofluorescence.

RESULTS

S100A7/psoriasin enhanced the expression of several differentiation markers and selectively increased the expression of TJ proteins (e.g. claudins and occludin), which are known to strengthen the TJ barrier. Furthermore, S100A7/psoriasin increased β-catenin and E-cadherin accumulation at cell-cell contact, and enhanced transepithelial electrical resistance while reducing the paracellular permeability of keratinocyte layers. The data suggest that S100A7/psoriasin-mediated regulation of the TJ barrier was via both the GSK-3 and MAPK pathways, as evidenced by the inhibitory effects of inhibitors for GSK-3 and MAPKs.

CONCLUSIONS

Our finding that S100A7/psoriasin regulates differentiation and strengthens TJ barrier function provides novel evidence that, in addition to antimicrobial and immunoregulatory activities, S100A7/psoriasin is involved in skin innate immunity.

Trigeminal pathways for hypertonic saline- and light-evoked corneal reflexes

Cornea-evoked eyeblinks maintain tear film integrity on the ocular surface in response to dryness and protect the eye from real or potential damage. Eyelid movement following electrical stimulation has been well studied in humans and animals; however, the central neural pathways that mediate protective eyeblinks following natural nociceptive signals are less certain. The aim of this study was to assess the role of the trigeminal subnucleus interpolaris/caudalis (Vi/Vc) transition and subnucleus caudalis/upper cervical cord (Vc/C1) junction regions on orbicularis oculi electromyographic (OOemg) activity evoked by ocular surface application of hypertonic saline or exposure to bright light in urethane anesthetized male rats. The Vi/Vc and Vc/C1 regions are the main sites of termination for trigeminal afferent nerves that supply the ocular surface, while hypertonic saline (saline=0.15-5M) and bright light (light=5k-20klux) selectively activate ocular surface and intraocular trigeminal nerves, respectively, and excite second-order neurons at the Vi/Vc and Vc/C1 regions. Integrated OOemg activity, ipsilateral to the applied stimulus, increased with greater stimulus intensities for both modalities. Lidocaine applied to the ocular surface inhibited OOemg responses to hypertonic saline, but did not alter the response to light. Lidocaine injected into the trigeminal ganglion blocked completely the OOemg responses to hypertonic saline and light indicating a trigeminal afferent origin. Synaptic blockade by cobalt chloride of the Vi/Vc or Vc/C1 region greatly reduced OOemg responses to hypertonic saline and bright light. These data indicate that OOemg activity evoked by natural stimuli known to cause irritation or discomfort in humans depends on a relay in both the Vi/Vc transition and Vc/C1 junction regions.

Perioperative outcomes of esophagectomy preceded by the laparoscopic transhiatal approach for esophageal cancer

This study was designed to determine the efficacy of esophagectomy preceded by the laparoscopic transhiatal approach (LTHA) with regard to the perioperative outcomes of esophageal cancer. The esophageal hiatus was opened by hand-assisted laparoscopic surgery, and carbon dioxide was introduced into the mediastinum. Dissection of the distal esophagus was performed up to the level of the tracheal bifurcation. En bloc dissection of the posterior mediastinal lymph nodes was performed using LTHA. Next, cervical lymphadenectomy, reconstruction via a retrosternal route with a gastric tube and anastomosis from a cervical approach were performed. Finally, a small thoracotomy (around 10 cm in size) was made to extract the thoracic esophagus and allow upper mediastinal lymphadenectomy to be performed. The treatment outcomes of 27 esophageal cancer patients who underwent LTHA-preceding esophagectomy were compared with those of 33 patients who underwent the transthoracic approach preceding esophagectomy without LTHA (thoracotomy; around 20 cm in size). The intrathoracic operative time and operative bleeding were significantly decreased by LTHA. The total operative time did not differ between the two groups, suggesting that the abdominal procedure was longer in the LTHA group. The number of resected lymph nodes did not differ between the two groups. Postoperative respiratory complications occurred in 18.5% of patients treated with LTHA and 30.3% of those treated without it. The increase in the number of peripheral white blood cells and the duration of thoracic drainage were significantly decreased by this method. Our surgical procedure provides a good surgical view of the posterior mediastinum, markedly shortens the intrathoracic operative time, and decreases the operative bleeding without increasing major postoperative complications.

Development of an improved RT-LAMP assay for detection of currently circulating rubella viruses

Rubella virus is the causative agent of rubella. The symptoms are usually mild, and characterized by a maculopapular rash and fever. However, rubella infection in pregnant women sometimes can result in the birth of infants with congenital rubella syndrome (CRS). Global efforts have been made to reduce and eliminate CRS. Although a reverse transcription-loop-mediated isothermal amplification (RT-LAMP) assay for detection of rubella virus has been reported, the primers contained several mismatched nucleotides with the genomes of currently circulating rubella virus strains. In the present study, a new RT-LAMP assay was established. The detection limit of this assay was 100-1000PFU/reaction of viruses for all rubella genotypes, except for genotype 2C, which is not commonly found in the current era. Therefore, the new RT-LAMP assay can successfully detect all current rubella virus genotypes, and does not require sophisticated devices like TaqMan real-time PCR systems. This assay should be a useful assay for laboratory diagnosis of rubella and CRS.

Abstract P3-13-08: A phase I study of weekly nab-paclitaxel in combination with S-1 in patients with metastatic breast cancer

Background: S-1 is an oral, fixed dose combination product comprised of tegafur, a fluoropyrimidine prodrug of 5-fluorouracil (5-FU), and modulators of 5-FU metabolism, 5-chloro-2.4-dihydrooxypyridine and oteracil potassium. S-1 is designed to provide oral delivery of 5-FU, a pyrimidine analog antimetabolite antineoplastic agent, while reducing the rate of degradation of 5-FU and its conversion in the gastrointestinal tract to its toxic phosphorylated metabolite. S-1 is active in breast cancer and a variety of solid tumors. nab™-Paclitaxel (nab-P) is a treatment option in metastatic breast cancer (MBC) (approved 260 mg/m2 q3w dosing schedule), and high activity of nab-P with single-agent weekly administration at 100 mg/m2 has been investigated in MBC as well as other disease states. Since these two agents differed in their mechanisms of action and toxicity profiles, we sought to test their combined activity in a phase I study of nab-P/S-1 for HER2-negative MBC. The primary objectives of this study was to determine the maximum tolerated dose (MTD) and recommended dose (RD) of nab-P/S-1 in patients with HER-2 negative MBC. The secondary objective of this study was to evaluate pharmacokinetic (PK) parameters of both agents.

Methods: Patients received treatment on 3 week cycles. S-1 was administered orally at a twice-daily dose of 65 mg/m2 (dose level 1 and 2b) or 80 mg/m2 (dose level 2a and 3) for 14 days and nab-P was administered as a 30-minute IV infusion at a dose of 100 mg/m2 on days 1 and 8 (dose level 1 and 2b) or 100 mg/m2 on days 1, 8 and 15 (dose level 2a and 3).

Results: Fifteen patients were enrolled in this study; nab-P/S-1 was given as first-line chemotherapy for MBC in 9 patients, and as second-line therapy subsequent to an anthracycline-containing therapy in 6 patients. At dose level 3, one patient experienced a DLT. The observed DLT was delay of initiation of next cycle, G4 neutropenia had not recovered to G1/G0 in a period defined on the protocol. No cases of febrile neutropenia were observed. Judged from the status of dose reduction and the extension of drug holidays (cycle start delay), and the occurrence of non-severe adverse events after 2 cycles, the dose level was not increased above level 3. Seven patients were able to be treated 10 cycles or more. Additionally, three patients were able to be treated 20 cycles or more. Among of the 12 patients who had a measurable lesion which was evaluable by RECISTv1.1, the overall response rate was 50%, with 1 CR, 5 PR, 4 SD, and 1 PD. Pharmacokinetics of Paclitaxel and 5-FU in the combination therapy were comparable to those after single-agent administration of nab-P and S-1, respectively.

Conclusion: Based on the results of this study, the RD was determined to be dose level 3 (S-1 80 mg/m2 twice daily plus nab-P 100 mg/m2 on days 1, 8, and 15). Since this combination therapy was generally well tolerated even with prolonged treatment, it is suggested that this combination therapy may be a promising treatment regimen in HER-2 negative MBC and merits further evaluation.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-13-08.