A modified MethyLight assay predicts the clinical outcomes of anti‐epidermal growth factor receptor treatment in metastatic colorectal cancer

DNA methylation status correlates with clinical outcomes of anti‐epidermal growth factor receptor (EGFR) treatment. There is a strong need to develop a simple assay for measuring DNA methylation status for the clinical application of drug selection based on it. In this study, we collected data from 186 patients with metastatic colorectal cancer (mCRC) who had previously received anti‐EGFR treatment. We modified MethyLite to develop a novel assay to classify patients as having highly methylated colorectal cancer (HMCC) or low‐methylated colorectal cancer (LMCC) based on the methylation status of 16 CpG sites of tumor‐derived genomic DNA in the development cohort (n = 30). Clinical outcomes were then compared between the HMCC and LMCC groups in the validation cohort (n = 156). The results showed that HMCC had a significantly worse response rate (4.2% vs 33.3%; P = .004), progression‐free survival (median: 2.5 vs 6.6 mo, P < .001, hazard ratio [HR] = 0.22), and overall survival (median: 5.6 vs 15.5 mo, P < .001, HR = 0.23) than did LMCC in patients with RAS wild‐type mCRC who were refractory or intolerable to oxaliplatin‐ and irinotecan‐based chemotherapy (n = 101). The DNA methylation status was an independent predictive factor and a more accurate biomarker than was the primary site of anti‐EGFR treatment. In conclusion, our novel DNA methylation measurement assay based on MethyLight was simple and useful, suggesting its implementation as a complementary diagnostic tool in a clinical setting.     

microRNA‐99a‐5p induces cellular senescence in gemcitabine‐resistant bladder cancer by targeting SMARCD1

Patients with advanced bladder cancer are generally treated with a combination of chemotherapeutics, including gemcitabine, but the effect is limited due to acquisition of drug resistance. Thus, in this study, we investigated the mechanism of gemcitabine resistance. First, gemcitabine‐resistant cells were established and resistance confirmed in vitro and in vivo. Small RNA sequencing analyses were performed to search for miRNAs involved in gemcitabine resistance. miR‐99a‐5p, selected as a candidate miRNA, was downregulated compared to its parental cells. In gain‐of‐function studies, miR‐99a‐5p inhibited cell viabilities and restored sensitivity to gemcitabine. RNA sequencing analysis was performed to find the target gene of miR‐99a‐5p. SMARCD1 was selected as a candidate gene. Dual‐luciferase reporter assays showed that miR‐99a‐5p directly regulated SMARCD1. Loss‐of‐function studies conducted with si‐RNAs revealed suppression of cell functions and restoration of gemcitabine sensitivity. miR‐99a‐5p overexpression and SMARCD1 knockdown also suppressed gemcitabine‐resistant cells in vivo. Furthermore, β‐galactosidase staining showed that miR‐99a‐5p induction and SMARCD1 suppression contributed to cellular senescence. In summary, tumor‐suppressive miR‐99a‐5p induced cellular senescence in gemcitabine‐resistant bladder cancer cells by targeting SMARCD1.     

Gestational trophoblastic disease of the fallopian tube.

Tubal gestational trophoblastic disease (GTD) was diagnosed in 16 (0.8%) of 2,100 women with GTD managed at the New England Trophoblastic Disease Center. Tubal partial mole, complete mole and choriocarcinoma were present in 5, 5 and 6 patients, respectively. Patients with tubal GTD were not clinically distinguishable from those with traditional tubal pregnancies. While only one patient with tubal mole developed metastases, four patients with tubal choriocarcinoma presented with metastases. All the patients achieved complete, sustained remission.     

Isolation and identification of embryo-derived platelet-activating factor in mice

We isolated a platelet-activating factor (PAF) derived from mouse embryos and identified it by bioassay utilizing washed rabbit platelets. We also tried further characterization of the factor by high-performance liquid chromatography (HPLC) and electron-impact mass spectrometry (EI-MS). 1. In the thin-layer chromatography (TLC) of the medium after a two day culture of 30 embryos at the two-cell stage, no obvious spot appeared at the site of 1-O-acetyl-2-O-alkyl-SN-glyceryl-3-phosphocholine (AGEPC). But a small, pale spot appeared at the site of lyso-AGEPC. 2. A remarkable aggregation activity was present at the site of the Rf and appearance time that was almost the same as for AGEPC in both TLC and HPLC. However, detection of the substance by UV absorption (203nm) in HPLC was unsuccessful. 3. The PAF activity shown in the culture medium was suspected to be 10(-10 - 10(-11) M/embryo and it was not inhibited by pretreatment with indomethacin and ADP scavenger. 4. Embryo-derived PAF had an HPLC appearance time 1-2 min. longer than that of synthetic AGEPC (C16). EI mass spectrum of embryo-derived PAF was partly inconsistent with that of synthetic AGEPC (C16). These results confirm the evidence of PAF release from mouse embryos and show the possibility that a far greater amount of its lyso-derivative is present in the culture medium. Embryo-derived PAF is presumed to be AGEPC or a substance resembling AGEPC in its chemical structure and some structural difference may exist between embryo-derived PAF and synthetic AGEPC (C16).     

Lower Incidence of K-ras Codon 12 Mutation in Flat Colorectal Adenomas than in Polypoid Adenomas

In order to clarify genetic changes in flat adenomas, K- ras codon 12 point mutations were examined in 56 flat adenomas, 81 polypoid adenomas and 42 cancers of colon and rectum. The mutation frequency in flat adenomas was 23% (13/56), significantly lower than that in polypoid adenomas (67%: 54/81) and cancers (76%: 32/42). Even mildly dysplastic adenomas or small (less than 5 mm) adenomas showed higher mutation incidence in polypoid type (62%, 57%) than in flat type (23%, 19%). Among flat adenomas, flat elevated lesions exhibited relatively higher mutation frequency than completely flat or depressed ones. As for cancers, 14 tumors (33%) contained mutations only in a minor tumor cell population, indicating that these mutations occur at a late stage of tumorigenesis. These results suggest that the adenoma-carcinoma sequence through flat adenomas may he different from that through polypoid adenomas, and genetic changes may be heterogeneous in colorectal carcinogenesis.     

Preoperative serum CA-125 levels in borderline tumors of the ovary.

Preoperative serum CA-125 levels were evaluated in 38 patients who underwent primary surgery for epithelial ovarian tumors of borderline malignancy at the Brigham and Women's Hospital and Massachusetts General Hospital between 1981 and 1990. Surgical staging was Stage I in 25 (66%) patients, Stage II in 2 (5%) patients, Stage III in 10 (26%) patients, and Stage IV in 1 (3%) patient. The mean sizes of mucinous and serous ovarian tumors were 21.9 and 10.3 cm, respectively (P = 0.0002). All 13 patients (100%) with mucinous tumors had Stage I disease, while 12 (50%) of 24 patients with serous tumors were Stage I. Combining all cell types, 10 (40%) of 25 patients with Stage I disease had an elevated preoperative CA-125 level, while 2 (100%) of 2, 9 (90%) of 10, and 1 (100%) of 1 patient with Stage II, III, and IV disease, respectively, had increased preoperative levels. Among patients with serous tumors, 3 (25%) of 12 Stage I patients had an elevated preoperative CA-125 level, while 11 (92%) of 12 Stage II-IV tumors had elevated levels (P less than 0.001). These data suggest that preoperative CA-125 level correlates with stage of disease in patients with serous borderline ovarian tumors.     

Improvement of risk factors for hip fracture by exercise intervention in elderly women

The purpose of this study was to investigate whether a 36-week complex exercise program helps to improve the risk factors for fall and hip fracture. Participant group for this study was 47 women in the range of age 65-68. The exercise program was conducted three times per week for 36 weeks. This study proved that the complex exercise program with weight bearing exercise at a moderate intensity and the gait training were highly effective in offsetting the decline in BMD, hormone metabolic substrate in elderly women. In addition, this exercise program had a positive effect on their postural stability.     

Susceptibilities of bacteria isolated from patients with lower respiratory infectious diseases to antibiotics (2000)

From October 2000 to September 2001, we collected the specimen from 410 patients with lower respiratory tract infections in 16 institutions in Japan, and investigated the susceptibilities of isolated bacteria to various anti-bacterial agents and antibiotics and patients' characteristics. Of 499 strains that were isolated from specimen (mainly from sputum) and assumed to be bacteria causing in inflammation, 493 strains were investigated. The breakdown of the isolated bacteria were: Staphylococcus aureus 78, Streptococcus pneumoniae 73, Haemophilus infiuenzae 99, Pseudomonas aeruginosa (non-mucoid) 64, P. aeruginosa (mucoid) 14, Klebsiella pneumoniae 25, Moraxella subgenus Branhamella catarrhalis 21, etc. Of 78 S. aureus strains, those with 4 micrograms/ml or more of MIC of oxacillin (methicillin-resistant S. aureus: MRSA) occupied 53.8%. Vancomycin and arbekacin had the most potent activities against MRSA as observed in 1999. The frequency of S. pneumoniae exhibiting low sensitivity to penicillin (penicillin-intermediate S. pneumoniae: PISP + penicillin-resistant S. pneumoniae: PRSP) was 38.4% being consistent with that in 1999 (34.7%). PRSP accounted for 11.0% of the total, being more than that in 1999 (3.0%). Carbapenems had strong activities against S. pneumoniae. Especially, panipenem inhibited the growth of all 73 strains at 0.125 microgram/ml. Generally, all drugs had strong activities against H. influenzae with MIC80s of 8 micrograms/ml or less. The drug that had the strongest activity against H. infiuenzae was levofloxacin, which inhibited the growth of 94 of the 99 strains at 0.063 microgram/ml. Tobramycin had a strong activity against P. aeruginosa (both mucoid and non-mucoid) with MIC80 of 1 microgram/ml. The mucoid strain was little isolated (14 strains) but the susceptibilities to all drugs were better than the non-mucoid strain. K. pneumoniae showed good susceptibilities to all drugs except ampicillin and the MIC80S were 2 micrograms/ml or less. Particularly, cefpirome, cefozopran, and levofloxacin had strong bactericidal activities against K. pneumoniae with MIC80s of 0.125 microgram/ml, and cefotiam, second-generation cephems, also had a favorable activity being MIC80 of 0.25 microgram/ml. Also, all drugs generally had strong activities against M. (B.) catarrhalis. MIC80s of all drugs were 2 micrograms/ml or less. The drug having the strongest activity was imipenem and levofloxacin inhibiting all 21 strains at 0.063 microgram/ml. Most of the patients with respiratory infection were aged 70 years or older, accounting for approximately a half of the total (44.4%). As for the incidence by the diseases, bacterial pneumonia and chronic bronchitis were the highest, being noted in 38.0% and 31.7% of all the patients, respectively. The bacteria frequently isolated from the patients with bacterial pneumonia were S. aureus (18.3%) and S. pneumoniae (16.1%). In contrast, H. infiuenzae (20.4%) and P. aeruginosa (both mucoid and non-mucoid: 16.7%) were frequently isolated from the patients with chronic bronchitis. Before the drug administration, the bacteria frequently isolated from all the patients were S. pneumoniae (24.3%) and H. infiuenzae (26.7%). The frequency of isolated S. pneumoniae tended to decrease with the increase in the number of administration days while that of isolated H. infiuenzae did not. The frequency of isolated P. aeruginosa tended to increase with the duration of administration. The isolated bacteria were comparable between the patients already treated with penicillins and cephems. In the patients treated with aminoglycosides, macrolides, and quinolones, P. aeruginosa was most frequently isolated (33.3 to 40.0%).