Association of NOD2 Mutations with Aggressive Periodontitis

Aggressive periodontitis (AgP) is characterized by rapid alveolar bone destruction and tooth loss early in life, and its etiology remains unclear. To explore the genetic risk factors of AgP, we performed genome-wide single-nucleotide polymorphism genotyping for identity-by-descent mapping and identified 32 distinct candidate loci, followed by whole exome sequencing with 2 pedigrees of AgP consisting of 3 cases and 1 control in 1 family and 2 sibling cases in the other. After variant filtering procedures and validation by targeted Sanger sequencing, we identified 2 missense mutations at 16q12 in NOD2 (p.Ala110Thr and p.Arg311Trp), which encodes nucleotide-binding oligomerization domain protein 2. We further examined 94 genetically unrelated AgP patients by targeted sequencing of NOD2 and found that 2 patients among them also carried the p.Arg311Trp variant. Furthermore, we found 3 additional missense mutations in this gene (p.His370Tyr, p.Arg459Cys, and p.Ala868Thr). These mutations either had not been previously observed or are extremely rare (frequency <0.001) in Asian populations. NOD2 plays a crucial role in innate immunity as an intracellular receptor initiating nuclear factor κB-dependent and mitogen-activated protein kinase-dependent gene transcription. These results demonstrated NOD2 as a novel gene involved in AgP.

Large-scale prospective pharmacogenomics study of oxaliplatin-induced neuropathy in colon cancer patients enrolled in the JFMC41-1001-C2 (JOIN Trial)

BACKGROUND

Peripheral sensory neuropathy (PSN) is a dose-limiting toxicity of oxaliplatin-based chemotherapy. Several genetic markers have been shown to predict oxaliplatin-induced PSN; however, results remain to be validated in a large-scale and prospective pharmacogenomics study.

PATIENTS AND METHODS

Among 882 patients enrolled in the JFMC41-1001-C2 (JOIN trial), which was designed to investigate the tolerability of adjuvant-modified FOLFOX6 (mFOLFOX6) in Japanese Patients with stage II or III colon cancers undergoing curative resection, 465 patients were eligible for this pharmacogenomics analysis. Twelve single-nucleotide polymorphisms (SNPs) were selected based on published data. The effect of each genotype on time to PSN onset was evaluated in all patients (n = 465) using the Cox proportional hazard model. For the association analysis between severity of PSN and 12 SNP markers, 84 patients who failed to complete 12 cycles of mFOLFOX6 from grade 0/1 PSN group were excluded because the termination of the protocol treatment had been caused by reasons other than PSN.

RESULTS

Comparison of grade 0/1 PSN with grade 2/3 PSN or grade 3 PSN showed no significant associations with any of the 12 SNP markers after adjustment for total dose of oxaliplatin. Time-to-onset analysis also failed to reveal any significant differences.

CONCLUSIONS

Our large-scale and prospective pharmacogenomics study of Japanese patients receiving protocol treatment of adjuvant mFOLFOX6 could not verify a role for any of the 12 SNP markers reported as being significantly associated with PSN. Considering the OR observed in this study (range: 0.76-1.89), further evaluation of these 12 SNP markers in the context of L-OHP-induced PSN is unlikely to be clinically informative.

Aurora-A is a determinant of tamoxifen sensitivity through phosphorylation of ERα in breast cancer

Despite the clinical success of tamoxifen, its resistance remains a major challenge in breast cancer. Here we show that Aurora-A determines tamoxifen sensitivity by regulation of oestrogen receptor (ER)α. Ectopic expression of Aurora-A decreases and depletion of Aurora-A enhances tamoxifen sensitivity in ERα-positive breast cancer. Elevated Aurora-A was significantly associated with the recurrence of ERα-positive tumours. Notably, Aurora-A inhibitor MLN8237, which is currently in clinical trial, synergizes with tamoxifen and overcomes tamoxifen resistance. Furthermore, Aurora-A interacts with and phosphorylates ERα on serine-167 and -305, leading to increase in ERα DNA-binding and transcriptional activity. Elevated levels of Aurora-A are significantly associated with disease-free survival in ERα-positive but not ERα-negative breast cancers. These data suggest that Aurora-A has a pivotal role in tamoxifen resistance and ERα is a bona fide substrate of Aurora-A. Thus, Aurora-A represents a prognostic marker in ERα-positive tumour and a critical therapeutic target in tamoxifen-resistant breast cancer, and Aurora-A inhibitor could be used as either an independent or concurrent agent in tamoxifen-resistant tumour.

Temporary blood pressure drop after bevacizumab administration is associated with clinical course of advanced colorectal cancer

Background:

A blood pressure drop after bevacizumab administration and its clinical significance have not been previously reported.

Methods:

Blood pressure data at 0, 90, and 180 min after a total of 162 bevacizumab administrations in 81 advanced colorectal cancer patients were retrospectively investigated.

Results:

Twenty-five patients (30%) demonstrated an average temporary drop of 20 mm Hg or more in systolic blood pressure. We classified these 25 patients as group A and the others as group B. Median time-to-treatment failure (TTF) was significantly longer in group A than in group B (291 vs 162 days; P=0.02). Furthermore, the proportion of patients who required intervention with antihypertensive drugs during bevacizumab treatment was significantly higher in group A than in group B (36% vs 4% P<0.01).

Conclusion:

This study suggests that a temporary blood pressure drop after bevacizumab administration could be a predictive marker for bevacizumab treatment.

[Lung adenocarcinoma with mixed subtypes which had been followed up for 5-years]

A 63-year-old female was admitted to our hospital for investigation of serum elevation of carcinoembryonic antigen (CEA). She underwent high anterior resection for a rectal cancer 5-years ago. Chest computed tomography (CT) obtained 5-years ago showed a nodule in the right S10, measuring 1.3 x 0.8 cm in size. The nodule was assessed as benign. Chest CT on admission showed the enlarged nodule with a pleural indentation, measuring 2.2 x 1.6 cm in size. Definitive diagnosis could not be established. Since it was difficult to exclude the possibility of malignancy, video-assisted partial resection was performed. Histological examination of the nodule revealed primary adenocarcinoma in frozen sections. Lobectomy with lymph node dissection was performed. The ultimate diagnosis was adenocarcinoma with mixed subtypes. The tumor was classified as stage IA with T1bN0M0. We reported this case because it was a rare slow-growing adenocarcinoma that had a 5-years clinical history before operation.

A case of progressive digital ischemia after early withdrawal of gemcitabine and S-1 in a patient with systemic sclerosis

The safety of chemotherapy for patients with systemic sclerosis is unclear, and there are few published reports documenting the side effects of chemotherapy in patients with this condition. Here, we report the case of a patient with systemic sclerosis who developed severe digital ischemia during combination gemcitabine/S-1 chemotherapy for pancreatic cancer. In spite of aggressive treatment, the digital ischemia progressively worsened and gangrenous changes developed in multiple fingers and toes. In this patient, the systemic sclerosis had been well controlled, with no digital ischemic symptoms for the previous 6 years, so this progressive clinical course in spite of aggressive treatment strongly suggests that the chemotherapy triggered or aggravated the digital necrosis. To the best of our knowledge, this is only the third reported case of a patient with systemic sclerosis developing digital necrosis after gemcitabine-based chemotherapy. The incidence of digital necrosis during chemotherapy in patients with systemic sclerosis is unknown, and the mechanism by which it occurs is unclear, but the three reports published to date, including the present case, suggest that physicians should be very cautious about administering gemcitabine-based chemotherapy to patients with systemic sclerosis. Any resulting digital ischemia might be refractory to treatment and worsen progressively, even if chemotherapy is withdrawn in the early stages of digital ischemia.

RhoA and RhoC are both required for the ROCK II-dependent promotion of centrosome duplication

CDK2-cyclin E triggers centrosome duplication, and nucleophosmin (NPM/B23) is found to be one of its targets. NPM/B23 phosphorylated by CDK2-cyclin E acquires a high binding affinity to Rho-associated kinase (ROCK II), and physically associates with ROCK II. The NPM/B23-binding results in super-activation of ROCK II, which is a critical event for initiation of centrosome duplication. The activation of ROCK II also requires the binding of Rho small GTPase to the auto-inhibitory region; hence the availability of the active Rho protein is an important aspect of the centrosomally localized ROCK II to properly initiate centrosome duplication. There are three isoforms of Rho (RhoA, B, and C), all of which are capable of binding to and priming the activation of ROCK II. Here, we investigated which Rho isoform(s) are involved in the activation of ROCK II in respect to the initiation of centrosome duplication. We found that both RhoA and RhoC, but not RhoB, were required for initiation of centrosome duplication, and over-activation of RhoA as well as RhoC, but not RhoB, promoted centrosome duplication and centrosome amplification.