Dosimetric impact of the respiratory motion of the liver dome in stereotactic body radiotherapy for spine metastasis: A planning study.

PURPOSE: This study aimed to clarify the dosimetric impact of the respiratory motion of the liver on stereotactic body radiation therapy (SBRT) for spine metastasis and examine the utility of introducing beam avoidance (beam-off at specific gantry angles). METHODS: A total of 112 consecutive patients who underwent SBRT for spine metastasis between 2018 and 2024 were examined. Overall, 15 patients who had lesions near the liver dome were included in this study. Retrospective treatment plans were generated using computed tomography (CT) images acquired during inhalation and exhalation to evaluate the dosimetric impact of respiratory motion of the liver. The dose difference (DD) and relative value (DD%) were evaluated using the dose-volume histogram (DVH) metrics, planning target volume Dmax, D95%, spinal cord D0.035 cc, and esophagus D2.5 cc. The magnitude of the liver movements was evaluated based on differences of liver size Lave at the isocentric axial plane between the inspiratory and expiratory CT images. RESULTS: The DD in almost all DVH metrics tended to increase when the liver moved away from the target during inhalation: For example, Mean ± $ \pm $ a standard deviation (SD) DD in PTV D95% for the treatment plan incorporating beam avoidance and those without beam avoidance was 0.5 ± $\pm$ 0.3 and 0.9 ± $ \pm $ 0.6 Gy, respectively. The spinal cord D0.035 cc for those shows 0.4 ± $ \pm $ 0.2 and 0.7 ± $ \pm $ 0.7 Gy, respectively. The treatment plans without beam avoidance also showed moderate or strong correlations between Lave and DD for almost all DVH metrics. No correlation was seen in the beam avoidance plan. The spinal cord D0.035 cc revealed approximately 1 Gy or +4% in DD when Lave was < -4 cm. CONCLUSIONS: Respiratory motion of the liver dome can cause substantial dosimetric discrepancies in the dose delivered to the spinal cord, although the extent depends on patient variables. Dose assessment should be performed for determining the appropriate means of respiratory management, such as breath-hold. Alternatively, beam avoidance effectively mitigates the impact.

Preferential B cell differentiation by combined immune checkpoint blockade for renal cell carcinoma is associated with clinical response and autoimmune reactions.

Combined immune checkpoint blockade (ICB) is effective therapy for renal cell carcinoma (RCC). However, the dynamic changes in circulating B cells induced by combined ICB have not been clarified. The present study prospectively examined 22 patients scheduled to receive ICB for unresectable or metastatic RCC between March 2018 and August 2021. Eleven patients received combined therapy with anti-PD-1 (nivolumab) and anti-CTLA-4 (ipilimumab), and the other 11 patients received nivolumab monotherapy. Comprehensive phenotypes of circulating immune cells obtained prior to and after ICB therapy were analyzed by flow cytometry. Although the proportion of naïve B cells among total B cells was significantly decreased, that of switched memory B cells was significantly increased after combined therapy. In responders, the proportion of B cells among peripheral blood mononuclear cells was significantly higher prior to ICB therapy, and the proportion of switched memory B cells among total B cells tended to increase after ICB therapy. Of note, the proportion of plasmablasts among total B cells was significantly increased after ICB therapy in patients who developed severe immune-related adverse events (irAEs), and the proportion of B cells among peripheral blood decreased significantly. Furthermore, in four of five patients who developed immune-related hypophysitis following combined therapy, anti-pituitary antibody was detected in the serum. These results suggested that immune-related hypophysitis was closely related to the increase in circulating plasmablasts. Collectively, this study suggests that combined ICB promotes the differentiation of B cell populations, which is associated with efficient tumor suppression and development of irAEs.

OX40 and LAG3 are associated with better prognosis in advanced gastric cancer patients treated with anti-programmed death-1 antibody.

BACKGROUND: Anti-PD-1 monoclonal antibody, nivolumab, has shown efficacy for advanced gastric cancer (AGC). However, the specific immune cell subsets predominantly activated during the period of anti-PD-1 therapy for AGC have not been clarified. METHODS: Peripheral blood of 30 AGC patients treated with nivolumab was prospectively obtained before the initial and second administrations and at the time of progressive disease (PD). The proportions of immune cell subsets and the serum concentrations of cytokines were systematically analysed by flow cytometry. Associations of subsets and serum cytokines with therapeutic effects were evaluated. RESULTS: After the initial administration, significant increases in activated central/effector memory, activated effector T cells, and activated T-helper 1 subsets were observed. At the time of PD, activated regulatory T cells, LAG3-positive CD4+/CD8+ T cells, and TIM3-positive CD4+/CD8+ T cells increased significantly. Significant positive correlations were shown between progression-free survival and proportions of LAG3-positive CD4+/CD8+ T cells and of OX40-positive CD4+/CD8+ T cells (log-rank p = 0.0008, 0.0003, 0.0035 and 0.0040). CONCLUSIONS: Nivolumab therapy enhances activation of central/effector memory and effector subsets of CD4+/CD8+ T cells. The expression levels of LAG-3 and OX40 on T cells correlated with the efficacy of nivolumab therapy and could be reasonable biomarkers for anti-PD-1 therapy.

Efficacy and safety analysis of chemotherapy for advanced colitis-associated colorectal cancer in Japan.

Chemotherapy for advanced colitis-associated colorectal cancer (CAC) has been insufficiently evaluated. The goal of this study was to clarify the efficacy and safety of chemotherapy for CAC in Japan. CAC patients who were treated with chemotherapy between 2005 and 2015 were retrospectively examined. Twenty-nine patients (median age, 48 years; 23 men) were assessed. Eighteen patients had ulcerative colitis, and 11 had Crohn's disease. Three ulcerative colitis and four Crohn's disease patients were in the active disease phase. Primary tumors were located in the rectum/anus (n=16), the left colon (n=9), or the right colon (n=4). Palliative or adjuvant chemotherapy was performed in 13 and 16 patients, respectively. First-line palliative chemotherapy regimens were as follows: fluorouracil, leucovorin, and oxaliplatin (FOLFOX; n=6), FOLFOX+bevacizumab (n=3), and others (n=4). Adjuvant chemotherapy regimens were S-1 (n=7), oxaliplatin-based (n=4) and others (n=5). In palliative chemotherapy, the objective response rate was 15%, and the median progression-free survival and overall survival were 182 and 315 days, respectively. In adjuvant chemotherapy, the 5-year relapse-free survival rate was 78%. Grade 3/4 adverse events (AEs) were observed in 16 patients (55%). Active and remission inflammatory bowel disease patients suffered grade 3/4 nonhematological AEs at an incidence of 71 and 23%, respectively (P<0.01). Dose reduction was required in 11 patients (38%), eight of whom required it for hematological AEs. Adjuvant chemotherapy for CAC exhibited sufficient efficacy, whereas modest efficacy was shown for palliative chemotherapy for CAC. AEs, particularly nonhematological AEs, were closely associated with disease activity of colitis.

Retrospective analysis of cardiovascular diseases related to chemotherapies for advanced solid tumor patients.

Appropriate management of cardiovascular diseases (CVDs) related to chemotherapy for solid tumors is important for safe oncologic treatment. However, prediction of the onset and progression of CVDs has not generally been established in Japan. We carried out a retrospective analysis of advanced or recurrent solid tumor patients who received chemotherapies in a single institution. Patient characteristics, chemotherapy regimens, adverse events, CVDs before chemotherapy, and diagnosis of CVDs in association with chemotherapy were assessed. During the period from April 2006 to March 2012, 394 patients were examined. Cardiac diseases (CDs), hypertension (HT), or arterial thrombosis or venous thromboembolism were prevalent in 37 (9.4%), 22 (5.6%), five (1.3%), and 14 (3.5%) cases, respectively. HT (14.5%) and venous thrombosis (5.8%) were frequent in patients who received bevacizumab-containing chemotherapy. Four cases with left ventricular dysfunction experienced a decrease of ejection fraction and early filling/atrial filling (E/A) and E/A tended to decrease before ejection fraction. Ninety (62.1%) of 145 cases showed an increase in the D-dimer (DD) level before chemotherapy, and a further increase in DD level was found when venous thrombosis occurred. Relative risks of the disease progression of HT, CD, and thromboembolism because of chemotherapy were 1.3, 1.9, and 3.6, respectively. A decrease in E/A and an increase in DD were suggested to be valuable for early diagnosis of the respective onsets of left ventricular dysfunction and venous thrombosis related to chemotherapy. We conclude that patients with previous CD tend to have disease progression of CD during chemotherapy.

The role of extrahepatic metabolism in the pharmacokinetics of the targeted covalent inhibitors afatinib, ibrutinib, and neratinib.

Despite the fact that much progress has been made recently in the development of targeted covalent inhibitors (TCIs), their pharmacokinetics (PK) have not been well characterized in the light of extrahepatic clearance (CLextH) by glutathione (GSH)/glutathione S-transferase (GST)-dependent conjugation attributable to the unique electrophilic structure (e.g., acrylamide moiety) of TCI compounds. In the present study, CLextH values were examined in rat, dog, and monkey to predict the contribution of CLextH to the PK of the TCIs afatinib, ibrutinib, and neratinib in humans. Afatinib and neratinib both underwent extensive conjugation with GSH in buffer and cytosol fractions of liver and kidney, whereas ibrutinib showed much lower reactivity/susceptibility to GSH/GST-dependent conjugation. The CLextH in each species was calculated from the difference between observed total body clearance and predicted hepatic clearance (CLH) in cryopreserved hepatocytes suspended in 100% serum of the corresponding species. The power-based simple allometry relating the CLextH for the unbound compound to animal body weight was applicable across species for afatinib and neratinib (R(2) ≥ 0.9) but not for ibrutinib (R(2) = 0.04). The predicted AUC after oral administration of afatinib and neratinib agreed reasonably closely with reported values in phase I dose-escalation studies. Comparisons of CLextH and CLH predicted that CLextH largely determined the PK of afatinib (>90% as a proportion of total body clearance) and neratinib (∼34%) in humans. The present method can serve as one of the tools for the optimization of PK in humans at the discovery stage for the development of TCI candidates.

Synthesis and Structure-Activity Relationships of 2-Aminoacetamide Derivatives as Peroxisome Proliferator-Activated Receptor α/γ Dual Agonists.

We describe the design, syntheses, and structure-activity relationships of novel zwitterionic compounds as nonthiazolidinedion-based peroxisome proliferator-activated receptor (PPAR) α/γ dual agonists. In our previous report, we obtained compound 1 showing potent PPARα/γ dual agonistic activities, together with a sufficient glucose-lowering effect in db/db mice. However, this compound possessed an issue, i.e., the 1,3,4-oxadiazole ring was not stable in acidic conditions. Thus, we carried out further optimization to improve the stability while maintaining the other favorable profile features including potent PPARα/γ dual agonistic activity. We addressed the issue by changing the oxadiazole ring to a bioisostere amide group. These amide derivatives were stable in acidic conditions and decreased plasma glucose and plasma triglyceride levels significantly without marked weight gain.

Initial safety and efficacy of cisplatin and gemcitabine combination chemotherapy for unresectable biliary tract cancer.

Cisplatin and gemcitabine combination chemotherapy has emerged as the standard treatment for advanced or recurrent biliary tract cancer and has been used in Japan since August 2011. We retrospectively reviewed and evaluated the toxicity and compliance of this combination chemotherapy from electronic medical records. From November 2011 to June 2012, 10 patients with unresectable biliary tract cancer underwent cisplatin and gemcitabine combination chemotherapy at our hospital. Grade 3/4 toxicities of neutropenia and thrombocytopenia were observed in 5 and 4 cases, respectively. Febrile neutropenia was observed in 3 cases. Grade 2 or worse anorexia was relatively common. Dose delays and reductions due to adverse events were needed in 8 patients. Cisplatin and gemcitabine combination chemotherapy for advanced biliary tract cancer can be safely performed with careful attention given to possible hematological toxicity and anorexia.

Myocardial metastasis from ZEB1- and TWIST-positive spindle cell carcinoma of the esophagus: A case report.

BACKGROUND: Metastatic cardiac tumors are known to occur more frequently than primary cardiac tumors, however, they often remain asymptomatic and are commonly discovered on autopsy. Malignant tumors with a relatively high frequency of cardiac metastasis include mesothelioma, melanoma, lung cancer, and breast cancer, whereas reports of esophageal cancer with cardiac metastasis are rare. CASE SUMMARY: The case of a 60-year-old man who complained of dysphagia is presented. Upper gastrointestinal endoscopy showed a submucosal tumor-like elevated lesion in the esophagus causing stenosis. Contrast-enhanced computed tomography showed left atrial compression due to the esophageal tumor, multiple liver and lung metastases, and a left pleural effusion. Pathological examination of a biopsy specimen from the esophageal tumor showed spindle-shaped cells, raising suspicion of esophageal sarcoma. The disease progressed rapidly, and systemic chemotherapy was deemed necessary, however, due to his poor general condition, administration of cytotoxic agents was considered difficult. Given his high Combined Positive Score, nivolumab was administered, however, the patient soon died from the disease. The autopsy confirmed spindle cell carcinoma (SCC) of the esophagus and cardiac metastasis with similar histological features. Cancer stem cell markers, ZEB1 and TWIST, were positive in both the primary tumor and the cardiac metastasis. CONCLUSION: To the best of our knowledge, there have been no prior reports of cardiac metastasis of esophageal SCC. This case highlights our experience with a patient with esophageal SCC who progressed rapidly and died from the disease, with the autopsy examination showing cardiac metastasis.

Spatial dynamics of CD39+CD8+ exhausted T cell reveal tertiary lymphoid structures-mediated response to PD-1 blockade in esophageal cancer.

Despite the success of immune checkpoint blockade (ICB) therapy for esophageal squamous cell cancer, the key immune cell populations that affect ICB efficacy remain unclear. Here, imaging mass cytometry of tumor tissues from ICB-treated patients identifies a distinct cell population of CD39+PD-1+CD8+ T cells, specifically the TCF1+ subset, precursor exhausted T (CD39+ Tpex) cells, which positively correlate with ICB benefit. CD39+ Tpex cells are predominantly in the stroma, while differentiated CD39+ exhausted T cells are abundantly and proximally within the parenchyma. Notably, CD39+ Tpex cells are concentrated within and around tertiary lymphoid structure (TLS). Accordingly, tumors harboring TLSs have more of these cells in tumor areas than tumors lacking TLSs, suggesting Tpex cell recruitment from TLSs to tumors. In addition, circulating CD39+ Tpex cells are also increased in responders following ICB therapy. Our findings show that this unique subpopulation of CD39+PD-1+CD8+ T cells is crucial for ICB benefit, and suggest a key role in TLS-mediated immune responses against tumors.

Fragment-Based Discovery of Allosteric Inhibitors of SH2 Domain-Containing Protein Tyrosine Phosphatase-2 (SHP2).

The ubiquitously expressed protein tyrosine phosphatase SHP2 is required for signaling downstream of receptor tyrosine kinases (RTKs) and plays a role in regulating many cellular processes. Genetic knockdown and pharmacological inhibition of SHP2 suppresses RAS/MAPK signaling and inhibit the proliferation of RTK-driven cancer cell lines. Here, we describe the first reported fragment-to-lead campaign against SHP2, where X-ray crystallography and biophysical techniques were used to identify fragments binding to multiple sites on SHP2. Structure-guided optimization, including several computational methods, led to the discovery of two structurally distinct series of SHP2 inhibitors binding to the previously reported allosteric tunnel binding site (Tunnel Site). One of these series was advanced to a low-nanomolar lead that inhibited tumor growth when dosed orally to mice bearing HCC827 xenografts. Furthermore, a third series of SHP2 inhibitors was discovered binding to a previously unreported site, lying at the interface of the C-terminal SH2 and catalytic domains.

Synthesis and structure-activity relationships of novel zwitterionic compounds as peroxisome proliferator activated receptor α/γ dual agonists with improved physicochemical properties.

We describe herein the design, syntheses and structure-activity relationships (SAR) of novel zwitterionic compounds as non-thiazolidinedion (TZD) based peroxisome proliferator activated receptor (PPAR) α/γ dual agonists. In the previous report, we obtained compound 1 showing potent PPARα/γ dual agonistic activities, together with a great glucose lowering effect in the db/db mice. However, this compound possessed fatal issues such as potent cytochrome P450 (CYP)3A4 direct inhibitory activity. Thus, we carried out the medicinal optimization to improve these while maintaining the potent PPAR agonistic activity. As a result, the issues were addressed by changing the furan ring to a low lipophilic 1,3,4-oxadiazole ring. Additionally, these oxadiazole derivatives exhibited a significant decrease in plasma glucose and plasma triglyceride levels without marked weight gain.

Discovery of a Novel ATP-Competitive MEK Inhibitor DS03090629 that Overcomes Resistance Conferred by BRAF Overexpression in BRAF-Mutated Melanoma.

Patients with melanoma with activating BRAF mutations (BRAF V600E/K) initially respond to combination therapy of BRAF and MEK inhibitors. However, their clinical efficacy is limited by acquired resistance, in some cases driven by amplification of the mutant BRAF gene and subsequent reactivation of the MAPK pathway. DS03090629 is a novel and orally available MEK inhibitor that inhibits MEK in an ATP-competitive manner. In both in vitro and in vivo settings, potent inhibition of MEK by DS03090629 or its combination with the BRAF inhibitor dabrafenib was demonstrated in a mutant BRAF-overexpressing melanoma cell line model that exhibited a higher MEK phosphorylation level than the parental cell line and then became resistant to dabrafenib and the MEK inhibitor trametinib. DS03090629 also exhibited superior efficacy against a melanoma cell line-expressing mutant MEK1 protein compared with dabrafenib and trametinib. Biophysical analysis revealed that DS03090629 retained its affinity for the MEK protein regardless of its phosphorylation status, whereas the affinity of trametinib declined when the MEK protein was phosphorylated. These results suggest that DS03090629 may be a novel therapeutic option for patients who acquire resistance to the current BRAF- and MEK-targeting therapies.

Discovery of Futibatinib: The First Covalent FGFR Kinase Inhibitor in Clinical Use.

Deregulating fibroblast growth factor receptor (FGFR) signaling is a promising strategy for cancer therapy. Herein, we report the discovery of compound 5 (TAS-120, futibatinib), a potent and selective covalent inhibitor of FGFR1-4, starting from a unique dual inhibitor of mutant epidermal growth factor receptor and FGFR (compound 1). Compound 5 inhibited all four families of FGFRs in the single-digit nanomolar range and showed high selectivity for over 387 kinases. Binding site analysis revealed that compound 5 covalently bound to the cysteine 491 highly flexible glycine-rich loop region of the FGFR2 adenosine triphosphate pocket. Futibatinib is currently in Phase I-III trials for patients with oncogenically driven FGFR genomic aberrations. In September 2022, the U.S. Food & Drug Administration granted accelerated approval for futibatinib in the treatment of previously treated, unresectable, locally advanced, or metastatic intrahepatic cholangiocarcinoma harboring an FGFR2 gene fusion or other rearrangement.

Design, synthesis and evaluation of novel zwitterionic compounds as PPARα/γ dual agonists (1).

We describe here the design, syntheses and structure-activity relationships (SAR) of novel zwitterionic compounds as non-thiazolidinedion (TZD) based peroxisome proliferator activated receptor (PPAR) α/γ dual agonists. We commenced the medicinal research with compound 1 originated by Eli Lilly, which was reported to possess PPAR α/γ dual agonist activity. We incorporated an amine linker and optimized it on the nitrogen of the linker, thereby envisioning the enhancement of the PPAR α/γ dual agonist activity together with altering the physicochemical properties. As a result, we could generate compounds showing the PPAR α/γ dual activity, especially among which compound 22e had a franylmethyl group on the linker and 2,6-dimethyl phenyl ring at the carboxylic acid head group furnishing a highly potent dual agonist activity, together with a great glucose lowering effect. Moreover, it remedied the lipid profile, that is, triglyceride without body weight gain in the db/db mice model.

Hyaluronic acid gel injection in rectovaginal septum reduced incidence of rectal bleeding in brachytherapy for gynecological malignancies.

PURPOSE: The purpose of this study was to report our initial clinical results of hyaluronic acid gel injection (HGI) in the rectovaginal septum (RVS) to reduce the incidence of rectal bleeding in vaginal brachytherapy for gynecologic malignancies. METHODS AND MATERIALS: Since 2008, CT based image-guided adaptive brachytherapy (IGABT) was initiated, and since 2015, HGI in the RVS was introduced in our institution. Vaginal cylinder with or without tandem or additional interstitial needles were applied for patients with gynecologic malignancies. Rectum dosimetric parameters and incidence of late rectum bleeding were compared between patients with and without HGI in the RVS. RESULTS: Between May 2008 and October 2017, 83 patients with gynecologic malignancies were treated with IGABT involving vaginal cylinder. Eleven patients who were treated for palliative intention were excluded, and 72 patients were subjected to the analysis. Of the total 72 patients 46 were with uterine cervical cancer, 19 uterine corpus cancer, five vaginal cancer, one vulvar cancer, and one ovarian cancer. Fifteen and 57 patients were irradiated with and without HGI in the RVS, respectively. With a median follow-up period of 57.7 (4.7-123.1) months, 30 (41.7%) patients suffered from radiation-related rectal bleeding. Patients with HGI in the RVS had a statistically significant lower incidence of rectal bleeding compared with those without it (13.3% vs. 49.1%, p = 0.01). CONCLUSIONS: HGI in the RVS reduced the incidence of late rectal bleeding for patients with gynecologic malignancies treated by vaginal cylinder and was not associated with HGI-procedure-related adverse events.

Schedule-dependent synergistic interaction between gemcitabine and oxaliplatin in human gallbladder adenocarcinoma cell lines.

To define the most effective combination schedule of gemcitabine and oxaliplatin (L-OHP), we investigated the in-vitro interaction between these drugs in a panel of four human gallbladder adenocarcinoma cell lines (HAG-1, GB-d1, NOZ, and G-415). Cytotoxic activity was determined by the WST-1 assay. Different schedules of the two drugs were compared and evaluated for synergism, additivity, or antagonism with a quantitative method based on the median-effect principle of Chou and Talalay. Cell cycle perturbation and apoptosis were evaluated by flow cytometry. Simultaneous and sequential treatments of gemcitabine followed by L-OHP exhibited synergistic effects in all four cell lines, whereas the reverse sequence largely showed an antagonism. Gemcitabine exclusively arrested cells at the G0/G1 phase, and L-OHP at the G2/M phase, as measured by flow cytometric analyses. Apoptosis was most prominent when cells were treated simultaneously or in a sequence gemcitabine followed by L-OHP, producing apoptosis in treated cells (27-30%). In contrast, the reverse sequence yielded only 6-7% induction of apoptosis, the rate being not significantly different from those induced by each drug singly. Moreover, this sequence dependence was further confirmed by the experiment, which compared the number of HAG-1 cells 7 days after these combination schedules. These findings suggest that the interaction of gemcitabine and L-OHP is highly schedule dependent, with the most efficacious interaction observed in either simultaneous combination or in a sequence combination of gemcitabine followed by L-OHP.

Phase I study of the sequential administration of S-1 and cisplatin for metastatic gastric cancer.

The combination of 5-fluorouracil (5-FU) and cisplatin (CDDP) has been reported to be active against metastatic gastric cancer (MGC) and great synergy has been shown in vivo and in vitro when 5-FU precedes CDDP. The sequential combination of S-1 (tegafur, oxonic acid, 5-chloro-2,4-dihydroxypyridine) followed by CDDP for MGC was investigated. A phase I trial applying increasing doses of oral administration of S-1 (65-80 mg/m(2)) for 21 days and increasing doses of CDDP (60-80 mg/m(2)) on day 22 every 35 days was conducted in order to determine the maximum tolerated dose (MTD) and recommended phase II dose. Patients with metastatic or recurrent gastric cancer, no prior chemotherapy, measurable disease, ECOG performance status less than 3 and adequate organ functions were eligible for the study. Three patients were treated at each dose level with escalation based on toxicity. Fifteen patients were included and evaluated for dose-limiting toxicity (DLT) and MTD. DLT included NCICTC grade 3 anorexia and fatigue in patients treated at S-1 80 mg/m(2) and CDDP 80 mg/m(2) (dose level 5). The other toxicities, grade 3 or higher, included neutropenia (grade 3) and nausea/vomiting (grade 3). Non-hematological toxicities were grade 1/2 and included diarrhea, nausea and stomatitis. There was no treatment-related mortality. Therefore, the recommended dose was a combination of S-1 at 80 mg/m(2) and CDDP at 70 mg/m(2). This sequential administration of S-1 and CDDP every 35 days is tolerable and warrants a phase II trial. A multicenter phase II study is currently under way.

Oxaliplatin-induced allergic reaction in patients with colorectal cancer in Japan.

BACKGROUND: Oxaliplatin is a platinum compound that is clinically effective for colorectal cancer (CRC), in combination with 5-fluorouracil (5-FU) and leucovorin (LV), and it is widely used for metastatic disease and for the adjuvant treatment of stage III CRC. With the increasing use of oxaliplatin in Japan, serious adverse events have been experienced other than hematologic and neurologic toxicities. METHODS: In order to clarify the clinical features of allergic reactions to oxaliplatin, we retrospectively investigated CRC patients who had received oxaliplatin-based chemotherapies. RESULTS: One hundred and twenty-five CRC patients who had been treated with FOLFOX regimens (containing oxaliplatin, 5-FU, and LV) were examined, and 21 patients (17%) were found to have developed allergic reactions. Sixteen patients (13%) had grade 1/2 adverse events, classified according to the common terminology criteria for adverse events (CTC-AE) version 3.0 and 5 (4%) had grade 3/4 adverse events. The allergic reaction appeared after a median number of nine cycles (range, 2-15 cycles). Previous chemotherapy included 5-FU/LV, CPT-11, and S-1. All of the patients with allergic reactions recovered completely when treated with antiallergy drugs. Oxaliplatin was reintroduced in 11 patients, with the use of prophylactic agents; allergic reaction to the reintroduction was not observed in 8 patients and grade 1/2 allergic reactions developed in 3 patients. No correlation was identified between allergic reaction and patients' background characteristics such as sex, history of allergy, and profile of other adverse events. CONCLUSION: Allergic reactions to oxaliplatin remain an important issue for patients being able to safely continue effective chemotherapies; further analysis will be needed to establish methods for the prediction and prophylaxis of such reactions.

Discovery of Novel Pyrido-pyridazinone Derivatives as FER Tyrosine Kinase Inhibitors with Antitumor Activity.

To obtain a new anticancer drug, we focused on FER tyrosine kinase. Starting with high-throughput screening with our in-house chemical library, compound 1, which has a pyridine moiety, was found. Referring to their X-ray crystal structure with FES proto-oncogene tyrosine kinase, as a surrogate of FER followed by chemical modification including scaffold hopping of the pyridine template, we discovered pyrido-pyridazinone derivatives with potent FER kinase inhibitory activity. Here, we disclose the structure-activity relationship on the scaffold and representative compound 21 (DS21360717), which showed in vivo antitumor efficacy in a subcutaneous tumor model.