[Comprehensive assessment of mismatch repair and microsatellite instability status in molecular classification of endometrial carcinoma]

Objective: To explore the concordance and causes of different mismatch repair (MMR) and microsatellite instability (MSI) detection results in endometrial carcinoma (EC) molecular typing. Methods: A total of 214 EC patients diagnosed from January 2021 to April 2023 were selected at the Department of Pathology, Peking University Third Hospital. The immunohistochemistry (IHC) results of MMR protein were reviewed. Tumor specific somatic mutations, MMR germline mutations, microsatellite scores and tumor mutation burden (TMB) were detected by next-generation sequencing (NGS) with multi-gene panel. Methylation-specific PCR was used to detect the methylation status of MLH1 gene promoter in cases with deficient MLH1 protein expression. In cases with discrepant results between MMR-IHC and MSI-NGS, the MSI status was detected again by PCR (MSI-PCR), and the molecular typing was determined by combining the results of TMB and MLH1 gene promoter methylation. Results: (1) In this study, there were 22 cases of POLE gene mutation subtype, 55 cases of mismatch repair deficient (MMR-d) subtype, 29 cases of p53 abnormal subtype, and 108 cases of no specific molecular profile (NSMP). The median age at diagnosis of MMR-d subtype (54 years old) and the proportion of aggressive histological types (40.0%, 22/55) were higher than those of NSMP subtype [50 years old and 12.0% (13/108) respectively; all P<0.05]. (2) Among 214 patients, MMR-IHC test showed that 153 patients were mismatch repair proficient (MMR-p), 49 patients were MMR-d, and 12 patients were difficult to evaluate directly. MSI-NGS showed that 164 patients were microsatellite stable (MSS; equal to MMR-p), 48 patients were high microsatellite instability (MSI-H; equal to MMR-d), and 2 patients had no MSI-NGS results because the effective sequencing depth did not meet the quality control. The overall concordance between MMR-IHC and MSI-NGS was 94.3% (200/212). All the 12 discrepant cases were MMR-d or subclonal loss of MMR protein by IHC, but MSS by NGS. Among them, 10 cases were loss or subclonal loss of MLH1 and (or) PMS2 protein. Three discrepant cases were classified as POLE gene mutation subtype. In the remaining 9 cases, 5 cases and 3 cases were confirmed as MSI-H and low microsatellite instability (MSI-L) respectively by MSI-PCR, 6 cases were detected as MLH1 gene promoter methylation and 7 cases demonstrated high TMB (>10 mutations/Mb). These 9 cases were classified as MMR-d EC. (3) Lynch syndrome was diagnosed in 27.3% (15/55) of all 55 MMR-d EC cases, and the TMB of EC with MSH2 and (or) MSH6 protein loss or associated with Lynch syndrome [(71.0±26.2) and (71.5±20.1) mutations/Mb respectively] were significantly higher than those of EC with MLH1 and (or) PMS2 loss or sporadic MMR-d EC [(38.2±19.1) and (41.9±24.3) mutations/Mb respectively, all P<0.01]. The top 10 most frequently mutated genes in MMR-d EC were PTEN (85.5%, 47/55), ARID1A (80.0%, 44/55), PIK3CA (69.1%, 38/55), KMT2B (60.0%, 33/55), CTCF (45.5%, 25/55), RNF43 (40.0%, 22/55), KRAS (36.4%, 20/55), CREBBP (34.5%, 19/55), LRP1B (32.7%, 18/55) and BRCA2 (32.7%, 18/55). Concurrent PTEN, ARID1A and PIK3CA gene mutations were found in 50.9% (28/55) of MMR-d EC patients. Conclusions: The concordance of MMR-IHC and MSI-NGS in EC is relatively high.The discordance in a few MMR-d EC are mostly found in cases with MLH1 and (or) PMS2 protein loss or MMR protein subclonal staining caused by MLH1 gene promoter hypermethylation. In order to provide accurate molecular typing for EC patients, MLH1 gene methylation, MSI-PCR, MMR gene germline mutation and TMB should be combined to comprehensively evaluate MMR and MSI status.

[Fumarate hydratase deficient uterine leiomyoma: a clinicopathological and molecular analysis of 80 cases]

Objective: To investigate the clinicopathologic and molecular characteristics of fumarate hydratase (FH) deficient uterine leiomyoma. Methods: Eighty cases of FH deficient uterine leiomyoma were diagnosed from April 2018 to September 2022 in Department of Pathology, Peking University Third Hospital. Sanger sequencing of FH gene exons (exon 1-10) were performed on tumor tissues and matched non-tumor tissues/peripheral blood for all cases. FH immunohistochemistry were performed in 74 cases; S-(2-succino)-cysteine (2SC) were also detected by immunohistochemistry in five cases. Results: Patients' age ranged from 18 to 54 (36.0±7.5) years, with more than 60% exhibiting clinical symptoms of multiple and large leiomyomas (the median diameter was 70 mm). More than four histologic features, including staghorn vasculature, alveolar-pattern edema, bizarre nuclei, oval nuclei arranged in chains, prominent eosinophilic nucleoli with perinucleolar haloes and eosinophilic intracytoplasmic globules were observed in 98.5% (67/68) patients. The immunohistochemical sensitivity of FH and 2SC were 97.3% and 100%, respectively. Based on the Sanger sequencing results, the cases were divided into germline variant group (31 cases), somatic variant group (29 cases) and no variant group (20 cases). Sixty-nine percent (20/29) of the patients with FH germline variation had clear family history. Conclusions: Clinical features, histological morphology, FH and 2SC immunohistochemistry and Sanger sequencing have their own significance and limitations in differential diagnosis of FH deficient uterine leiomyoma. In clinical practice, the above information should be fully integrated and studied for accurate pathologic diagnosis and selection of patients with FH germline variation.

[Activation of JAK/STAT in ovarian high-grade serous cancers and its prognostic significance]

OBJECTIVE

The activation of Janus kinase (JAK) and signal transducers and activators of transcription (STAT) plays an important role in the prognosis and targeted therapy of ovarian high-grade serous carcinoma (HGSC). Utilizing simple and practicable technique, this study aimed to evaluate the activation of JAK/STAT signaling pathway in ovarian HGSC patients, and investigated the correlation between the activation of JAK/STAT signaling pathway and the prognosis of the HGSC patients.

METHODS

We performed immunohistochemistry of phosphorylated STAT3 (pSTAT3) and phosphorylated STAT5 (pSTAT5) on paraffin imbedded slides of 73 ovarian HGSC patients, and evaluated the expression level and range of both markers. According to the grading score of the immunostaining of pSTAT3 and pSTAT5, we divided the 73 ovarian HGSC cases into STAT3 low/high expression and STAT5 low/high expression groups, and analyzed the prognosis of the patients in different groups, in order to explore the relationship between the expression of pSTAT3 and pSTAT5 proteins and the prognosis of the HGSC patients.

RESULTS

Some of the ovarian HGSC cases showed high expression of pSTAT3 and pSTAT5 protein level, which was related to the poorer prognosis of the HGSC patients. There was a significant difference in the expression level of pSTAT3 and pSTAT5 between the patients with better prognosis (survival time ≥3 years) and poorer prognosis (survival time < 3 years). The patients with higher protein expression of pSTAT3, pSTAT5 or both markers might have poorer prognosis, with significant shorter progression-free survival time and overall survival time (P < 0.001).

CONCLUSION

Immunostaining of pSTAT3 and pSTAT5 proteins might be helpful to evaluate and predict the prognosis of the ovarian HGSC patients, and to identify the patients who might have higher chances to respond to the STAT inhibitors and anti-angiogenesis therapy.

[Uterine POLE mutant endometrioid carcinoma combined with human papilloma virus-associated cervical adenocarcinoma: A case report and literature review]

Independent primary uterine and cervical adenocarcinoma are rare and difficult to identify their origins, which makes treatment decision difficult. A 46-year-old female with endometrioid carcinoma and adenocarcinoma, human papilloma virus (HPV)-associated of the uterine cervix was reported. The patient presented with increased menstrual flow, contact bleeding and watery leucorrhea for more than one year, and the imaging findings showed abnormal uterine morphology, irregular margins, and multiple abnormal signals in uterine cavity and myometrium, which suggested multiple leiomyomas of the uterus. The signal intensity in the right muscle layer was markedly enhanced, suggesting a smooth muscle tumor of uncertain malignant potential. A large number of cystic hypointensity was seen in the cervix, and multiple cysts were considered. The initial preoperative diagnosis was multiple leiomyoma of the uterus, and a hysterectomy operation was planned. During the operation, the uterus was sent for frozen sections. There was a mass in the endometrium of the fundus, with a soft grayish-red cut surface and a clear border with the myometrium, and there was a grayish-white nodule in the cervix with a hard grayish-white cut surface. The two masses were well demarcated from each other, and the distance between them was 30 mm. The result of the frozen sections indicated the malignant tumor of the endometrium, and the extended hysterectomy+pelvic lymphadenectomy+partial resection of the greater omentum was performed. After the operation, the paraffin sections were sent to the Department of Pathology of the Peking University Third Hospital for histochemistry, POLE gene sequencing and HPV RNAscope tests, and the final diagnosis was a synchronous endometrioid carcinoma (POLE-mutant according to the WHO classification) and an adenocarcinoma, HPV-associated of the uterine cervix. Now the patient had been treated with 2 cycles of chemotherapy and her condition was fine. Through the analysis of the histological, immunohistochemical and molecular detection results of this case, the importance of applying HPV RNAscope and TCGA molecular typing in the diagnosis of cervical adenocarcinomas and endometrial carcinomas was emphasized. At the same time, gynecologists should not blindly rely on intraoperative frozen sections, and should pay attention to preoperative pathological examination, and make appropriate operation methods according to the results in order to prevent passivity in the surgery.

Identification of salivary autoantibodies as biomarkers of oral cancer with immunoglobulin A enrichment combined with affinity mass spectrometry

Globally, oral cavity squamous cell carcinoma (OSCC) is one of the most common fatal illnesses. Its high mortality is ascribed to the fact that the disease is often diagnosed at a late stage, which indicates an urgent need for approaches for the early detection of OSCC. The use of salivary autoantibodies (autoAbs) as OSCC biomarkers has numerous advantages such as easy access to saliva samples and efficient detection of autoAbs using well-established secondary reagents. To improve OSCC screening, we identified OSCC-associated autoAbs with the enrichment of salivary autoAbs combined with affinity mass spectrometry (MS). The salivary IgA of healthy individuals and OSCC patients was purified with peptide M-conjugated beads and then applied to immunoprecipitated antigens (Ags) in OSCC cells. Using tandem MS analysis and spectral counting-based quantitation, the level of 10 Ags increased in the OSCC group compared with the control group. Moreover, salivary levels of autoAbs to the 10 Ags were determined by a multiplexed bead-based immunoassay. Among them, seven were significantly higher in early-stage OSCC patients than in healthy individuals. A marker panel consisting of autoAbs to LMAN2, PTGR1, RAB13, and UQCRC2 was further developed to improve the early diagnosis of OSCC.

Genomic and Molecular Signatures of Successful Patient-Derived Xenografts for Oral Cavity Squamous Cell Carcinoma

Background

Oral cavity squamous cell carcinoma (OSCC) is an aggressive malignant tumor with high recurrence and poor prognosis in the advanced stage. Patient-derived xenografts (PDXs) serve as powerful preclinical platforms for drug testing and precision medicine for cancer therapy. We assess which molecular signatures affect tumor engraftment ability and tumor growth rate in OSCC PDXs.

Methods

Treatment-naïve OSCC primary tumors were collected for PDX models establishment. Comprehensive genomic analysis, including whole-exome sequencing and RNA-seq, was performed on case-matched tumors and PDXs. Regulatory genes/pathways were analyzed to clarify which molecular signatures affect tumor engraftment ability and the tumor growth rate in OSCC PDXs.

Results

Perineural invasion was found as an important pathological feature related to engraftment ability. Tumor microenvironment with enriched hypoxia, PI3K-Akt, and epithelial–mesenchymal transition pathways and decreased inflammatory responses had high engraftment ability and tumor growth rates in OSCC PDXs. High matrix metalloproteinase-1 (MMP1) expression was found that have a great graft advantage in xenografts and is associated with pooled disease-free survival in cancer patients.

Conclusion

This study provides a panel with detailed genomic characteristics of OSCC PDXs, enabling preclinical studies on personalized therapy options for oral cancer. MMP1 could serve as a biomarker for predicting successful xenografts in OSCC patients.

[Complications of Da Vinci robot thyroid surgery by bilateral axillo-breast approach]

Objective: To evaluate the complications of Da Vinci robotic thyroid surgery by bilateral axillo-breast approach. Methods: A retrospective analysis of complications was conducted on 1, 198 cases of Da Vinci robotic thyroid surgery by bilateral axillo-breast approach of the 960 th Hospital of the People's Liberation Army from February 2014 to March 2020. There were 263 men and 935 women, age ranged from 9 to 68 years old, and included 288 benign lesions and 910 malignancies according to preoperative imaging examination, FNAC, and intraoperative frozen pathology. Results: Surgical complications occurred in 187 (15.61%) patients, including 10 cases of temporary larynx nerve injury (0.83%), 1 case of permanent larynx nerve injury (0.08%), and 152 cases of temporary hypoparathyroidism (12.69%), no permanent hypoparathyroidism, 1 case of hypoglossal injury (0.08%), 2 cases of facial nerve jaw branch damage (0.17%), 2 cases of trachea injury (0.17%), no esophagus damage, 5 cases of celiac leakage (0.42%), 3 cases of neck skin adhesion (0.25%), 2 cases of subdermal bleeding (0.17%), 2 cases of skin burns (0.17%), 5 cases of hematoma (0.42%), 1 case of cephalic artery rupture (0.08%), 1 case of jugular vein rupture (0.08%), no tumor cultivation, no arm plex nerve, accessory nerve or phrenic nerve damage. Conclusion: Da Vinci robot thyroid surgery by bilateral axillo-breast approach is safe, with less severe complications.

Cotargeting CHK1 and PI3K Synergistically Suppresses Tumor Growth of Oral Cavity Squamous Cell Carcinoma in Patient-Derived Xenografts

Oral cavity squamous cell carcinomas (OSCCs) are aggressive tumors, and their recurrence leads to poor prognosis and reduced survival rates. This study aimed to identify therapeutic targets and to evaluate the efficacy of targeted inhibitors in OSCC patient-derived xenograft (PDX) models. Herein, we reported that OSCC PDXs recapitulated the genomic signatures of their paired primary tumors and the expression of CHEK1, PIK3CA, and PIK3CD was significantly upregulated in OSCC. The antitumor efficacy of CHK1 inhibitors (PF477736, AZD7762, LY2606368) and PI3K inhibitors (BYL719, GDC0941, GSK1059615) was investigated in OSCC cell lines and PDX models. Targeting either CHK1 or PI3K effectively inhibited cell proliferation and colony formation by inducing cell cycle arrest and apoptosis in in vitro cell-based assays. Cisplatin-based chemotherapy combined with CHK1 inhibitor treatment synergistically inhibited cell proliferation by suppressing CHK1 phosphorylation and inducing PARP cleavage. Furthermore, compared with monotherapy, cotreatment with CHK1 and PI3K inhibitors exerted synergistic anticancer effects by suppressing CHK1, AKT, and 4E-BP1 phosphorylation. In summary, our study identified CHK1 and PI3K as promising targets, especially in a dual treatment strategy combining a CHK1 inhibitor with cisplatin or a PI3K inhibitor as a novel therapeutic approach for OSCC patients with aberrant cell cycle regulation and PI3K signaling activation.

[Clinicopathological study of SET subtype of ovarian high-grade serous carcinoma]

Objective: To investigate the clinicopathological characteristics and significance of solid, endometrioid and transitional (SET) ovarian high-grade serous carcinoma (HGSC). Methods: A total of 408 cases of ovarian HGSC admitted to Peking University People's Hospital from January 2011 to September 2016 were collected. (1) According to the proportion of tumors with SET form in all tumors, they were divided into three groups: HGSC-classic group (<25%), HGSC-SET Ⅰ (25%-50%) and HGSC-SET Ⅱ (>50%) group. The clinical and pathological characteristics of three groups of ovarian HGSC patients were compared respectively. (2) According to the growth pattern, that was, the proportion of pushing/expanding invasive tumors in the whole pelvic disseminated tumors of pelvic disseminated tumors, the three groups were divided into four subgroups: group A (0-25%), group B (26%-50%), group C (51%-75%) and group D (>75%). Differences in progression-free survival (PFS) among the four subgroups in each group were compared respectively. Results: The median age of 408 cases with ovarian HGSC was 63.3 years (47-78 years), including 152 cases premenopausal and 256 cases postmenopausal. Among 408 cases of ovarian HGSC, 290 cases were in HGSC-classic group, 91 cases in HGSC-SET Ⅰ and 27 cases in HGSC-SET Ⅱ group. (1) There were significant differences in age, proportion of menopausal patients, tumor necrosis (including map necrosis or acne necrosis), response rate to primary chemotherapy, 5-year mortality rate and PFS between HGSC-SET Ⅰ and HGSC-SET Ⅱ (P<0.05). There was no significant difference among the above indexes between HGSC-SET Ⅰ and HGSC-SET Ⅱ (P>0.05). In HGSC-classic group, HGSC-SET Ⅰ and HGSC-SET Ⅱ, the proportion of family members or patients with history of epithelial ovarian cancer or breast cancer increased in turn, and the detection rate of serous tutal intraepithelial carcinoma (STIC) in fallopian tube tissue decreased in turn. There were significant differences between the two groups (P<0.05). (2) In HGSC-classic group, there were 147 cases in group A, 124 cases in group B and 19 cases in group C (0 case in group D), with median PFS of 17.4, 17.7 and 16.5 months respectively (P<0.05); 10, 6, 29 and 46 cases in group A, B, C and D in HGSC-SET Ⅰ, with median PFS of 9.6, 12.7, 30.1 months and 39.0 months respectively, which there were significant difference among group A and C and D (all P<0.05); among group B, C and D group in HGSC-SET Ⅱ, there were respectively 3, 12 and 12 cases (0 case in group A), and the median PFS was 13.5, 34.2 and 47.8 months (P<0.05). PFS was positively correlated with the increase of push/expansive infiltration ratio. Conclusions: The detection rate of STIC in ovarian HGSC patients with SET is higher, the effect of primary chemotherapy is better, and PFS is prolonged. PFS was significantly prolonged in patients with pelvic disseminated tumors of HGSC-SET, the infiltration of which were predominated by pushing or expanding boarder.

[Clinical application of TCGA molecular classification in endometrial endometrioid carcinoma]

Objective: To explore molecular characteristics of endometrial endometrioid cancer according to The Cancer Genome Atlas (TCGA) based molecular classification of endometrial carcinomas and to confirm simple and clinically applicable surrogate methodologies in pathological practice. Methods: Two hundred and twenty-eight cases of endometrial endometroid adenocarcinomas (EnACs) collected from August 2001 to August 2017 from Peking University Health Science Center, Peking University Third Hospital were molecularly categorized by using Sanger sequencing for the exonuclease domain mutations (EDM) of POLE, and by immunohistochemistry for p53 and mismatch repair (MMR) proteins. The cohort was classified into polymerase-E exonuclease domain mutation (POLE EDM), mismatch repair deficiency (MMR-D), p53 abnormal (p53-abn) and p53 wild type (p53-wt) groups. The correlation between molecular subgroups and the clinical-pathological features including prognosis were analyzed. Results: The cohort was distributed as follows: 11(4.8%) POLE EDM, 47(20.6%) MMR-D, 9(4.0%) p53-abn and 161(70.6%) p53-wt. p53-wt subgroup patients demonstrated significantly higher lymph node metastasis (P=0.011) and more advanced stage (P=0.036) than those of somatic hypermutation group cases (POLE EDM and MMR-D). In the FIGO grade 2-3 EnACs cohort, TCGA molecular subtyping was significantly correlated with progression-free survival and overall survival (P=0.043). POLE EDM subgroup had the best survival, while p53-abn subgroup had the worst. Conclusions: Identification of POLE EDM and MMR-D subgroups provides independent and highly valuable prognostic information beyond established histological classification. Based on immunohistochemistry of MMR, p53 and POLE mutational analysis, this pragmatic molecular classification scheme can be served as a reliable surrogate for TCGA molecular classification, which has potential to be used routinely in Chinese pathological practice.

[Application and clinical significance of Silva pattern system in invasive endocervical adenocarcinoma]

Objective: To investigate the significance of Silva pattern system about clinical application in invasive endocervical adenocarcinoma. Methods: Data obtained from the Maternity Affiliated Hospital of Dalian Medical University was analyzed, 78 endocervical adenocarcinoma cases were included from December, 2006 to August, 2017. The average age of patients was (45.1±9.1) years old (ranged 27-71 years old). Clinical stage: stageⅠa 26 cases and Ⅰb 49 cases and stage Ⅱa 3 cases. All pathological slides were reviewed, stratified cases into pattern A, B and C according to Silva system criteria. Clinicopathological parameters of three Silva subgroups were analyzed, χ(2) test was used to investigate the correlation of Silva system and clinicopathological parameters. Follow-up data were collected until Jan. 3rd, 2018. The median follow-up time was 41 months (ranged 5-90 months). Kruskal-Wallis H test and Fisher test were used to analyze prognoses among different Silva subgroups. Results: (1) Silva A cases accounted for 38% (30/78) of all patients, 24 cases were stageⅠa, 6 cases were stageⅠb. The median tumor thickness was 2.1 mm (ranged 1.0-10.0 mm). No lymph vascular space invasion (LVSI) and perineural invasion (PNI) was detected, and all lymph node (LN) were negative for metastatic carcinoma. All patients were alive and had no evidence of recurrence. About 21% (16/78) cases were classified as Silva B, including 2 stage Ⅰa and 14 stage Ⅰb. The median tumor thickness was 5.2 mm (ranged 2.0-11.0 mm). Several patients had LVSI (4/16), LN metastasis (1/10) or PNI (1/16), but there was no recurrence or death. Thirty two (41%, 32/78) cases were Silva C, including 29 stage Ⅰb and 3 stage Ⅱa. The median tumor thickness was 11.5 mm (ranged 4.0-21.0 mm). The incidence of LVSI (53%, 17/32), LN metastasis (31%, 8/26) or PNI (16%, 5/32) was significantly increased. There were two recurrent cases and one death cases. (2) Statistical data demonstrated that Silva pattern system was closely correlated with clinicopathological parameters, such as clinical stage (r=0.754, P=0.000), tumor depth (P=0.000) and LVSI (r=0.534, P=0.000). But there was no correlation between Silva system and LN metastasis or PNI (all P>0.05). (3) Silva subgroups demonstrated no significant difference in recurrence and death (P>0.05). Conclusions: The application of Silva pattern system could effectively predict the prognosis of patients. It may be helpful to select reasonable operation before surgery and to realize individualized treatment of cervical adenocarcinoma.

[BABA of da Vinci robot thyroid surgery in the standard treatment of thyroid cancer surgery]

Thyroid cancer is the most common malignant tumor in endocrine surgery. Surgery is the first choice for most patients with thyroid cancer. Da Vinci robot system as the auxiliary system is the most advanced endoscopic surgery, largely to fill the cavity mirror device cannot bend, complex operation and so on insufficiency, has now become an important way of surgical treatment of thyroid cancer, and its curative effect, high safety, but because of the economic cost is higher, is currently not widespread popularity.

[Study of the association between polymorphism of persistent obesity, human leptin gene/leptin receptor gene and molecular subtypes of breast cancer]

Objectives: To explore the association between the polymorphism of persistent obesity and genetic variations in the LEP (human leptin gene, LEP) and LEPR (leptin receptor gene, LEPR) genes and different molecular subtypes of breast cancer. Methods: All 703 female patients of breast cancer diagnosed by histopathology in the Sichuan Cancer Hospital or the West China Hospital, excluding patients with metastatic breast cancer or mental disease, were selected as cases from April 2014 to May 2015. At the same time, 805 healthy women received physical examination in medical examination center of Sichuan People Hospital or Shuangliu maternal and child health care hospital, excluding those with therioma, breast disease, and mental disease, were enrolled in control group. A uniform questionnaire was used to collect general information including demographic characteristic, reproductive history height, weight, and so on. And the obesity status in recent 10 years was judged. Time of Flight Mass Spectrometer was used to determine the genotypes of LEP rs7799039, LEPR rs1137100 and LEPR rs1137101, while the multinomial logistic regression analysis was conducted to estimate the effect of risk factors related to breast cancer in different molecular subtypes; and then, the association between polymorphism of persistent obesity, the LEP, LEPR genes and breast cancer of different molecular subtypes was analyzed by binary logistic regression models. Results: The average age of controls was (48.98±8.83) years old, while the age of cases of TNBC, Luminal A, Luminal B, and HER-2+ were (51.43±11.33), (49.94±10.10), (49.73±9.38), (50.50±9.04) years old, respectively. The frequency of genotype LEP rs7799039, LEPR rs1137100 and LEPR rs1137101 in control group was separately 74.8%(1 157/1 546), 83.6%(1 339/1 602) and 88.4%(1 416/1 602); while 77.6% (1 074/1 384), 82.4% (1 155/1 402) and 87.9% (1 232/1 402) respectively in case group. Compared with non-persistent obesity subjects, the persistent obesity ones showed an increased risk in TNBC (OR=3.58, 95%CI: 1.90-6.72), Luminal A (OR=2.65, 95%CI: 1.35-5.21) and Luminal B (OR=1.90, 95%CI: 1.26-2.89) breast cancer. LEP rs7799039-AA was relevant with the upward risk of Luminal B independently (OR=1.30, 95%CI: 1.00-1.69). Besides, persistent obesity was found to have a combined effect on Luminal B (β=3.34, 95% CI: 1.00-11.12) with LEPR rs1137101-GG. Conclusion: Persistent obesity could increase the potential risk of TNBC, Luminal A and Luminal B breast cancer. Women who were suffered from persistent obesity with a genotype of LEPR rs1137101-GG were more susceptible to Luminal B breast cancer.

[Association of XRCC1 gene polymorphism and low dose ionizing radiation with peripheral blood lymphocyte micronucleus]

Objective: To explore the effects of X-ray repair cross complementing gene 1 (XRCC1) polymorphism and low dose ionizing radiation exposure on radiology professionals' peripheral blood lymphocyte micronucleus. Methods: A matched case-control study was designed. From 2013 to 2015, 1 102 radiology professionals with micronucleus test rusults, and 45 cases with present micronucleus were enroled into case group. 180 diagnostic radiology technicians detecting no micronucleus were chosen as control group, cases and controls were 1∶4 mached on gender, age ≤40 or >40 years old. According to the detection of micronucleus levels (0‰, 1‰, 2‰) , the objects of our study were divided into the reference group, the low detection group and the medium detection group. The form of radiation workers' occupational health examination was used to collect the general baseline of the research objects, history of smoking, drinking, poisonous and harmful material exposure, past medical history, accumulated illuminated dose and lymphocyte micronucleus rates (‰) , etc. Using restriction fragment length polymorphism polymerase chain reaction (RFLP-PCR) technology for genotyping; Compared the baseline data and radiation exposure level between the differentmicrokernel detection groups; Adopted multivariate logistic regression to analysis the combination effect of XRCC1 Arg399Gln gene polymorphism and accumulated illuminated dosefor micronucleus rate. Results: The accumulated illuminated dose in the reference group, the low detection group and the medium detection group were (23.44±15.23) , (21.76±2.56) , (24.22±18.61) mSv, respectively. There was no statistically significant difference among the groups (P>0.05) . Under the dominant inheritance mode, after adjusted age, smoking and drinking factors, the results suggested that XRCC1 Arg399Gln micronucleus medium detection group compared with the reference group, Arg399Gln-GG as reference, Arg399Gln-GA+AA decreased the occurrence of micronucleus (OR=0.175, 95%CI: 0.036-0.848) . Arg194Trp and Arg280His did not affect the incidence of micronucleus (P>0.05) . Did not find the combination effect of XRCC1 Arg399Gln gene polymorphism and accumulated illuminated dose for micronucleus rate (P>0.05) . Conclusion:XRCC1 Arg399Gln gene polymorphism can affect the incidence of micronucleus, and carrying the XRCC1 Arg399Gln-GA+AA genotype is a protective factor of micronucleus's occurrence, but low dose ionizing radiation may not affect the occurrence of micronucleus independently.

Effects of hyper- and hypothyroid on expression of thyroid hormone receptor mRNA in rat myocardium

Thyroid dysfunction is classified into hyperthyroidism and congenital hypothyroidism (CH). Both hyperthyroidism and CH can cause heart lesions; however, the mechanisms involved remain unclear. The left ventricle was collected from eu-, hyper-, and hypothyroid rat. RNA was extracted and reverse-transcripted to cDNA. Real-time fluorescence quantitation-PCR was used to quantify the differential expression of thyroid hormone receptor (TR) subtype mRNA among eu-, hyper-, and hypothyroid rat myocardium. Here, we show that compared with the normal myocardium, TRalpha1 mRNA expression was upregulated by 51% (P<0.01), TRalpha2 mRNA expression was downregulated by 58% (P<0.01), and TRbeta1 mRNA expression remained unchanged in hyperthyroid rat myocardium (P>0.05). TRalpha1, TRalpha2, and TRbeta1 were expressed in normal and hypothyroid rat myocardium throughout the developmental process. In hypothyroid rats, myocardial TRalpha1 mRNA expression was generally downregulated and the expression peak appeared late. Myocardial TRalpha2 mRNA expression was generally upregulated and the expression peak appeared late. Myocardial TRbeta1 mRNA expression was generally downregulated and changed similarly with the control group. In addition, the hypogenetic myocardium can be seen in the hypothyroid rat by pathology study. Taken together, the abnormal expression of TR subtype mRNA may have a close relationship with the pathogenesis of CH and hyperthyroidism heart disease.

Heritability of subclinical atherosclerosis in Latino families ascertained through a hypertensive parent

Although clinical coronary heart disease and many cardiovascular risk factors are well known to aggregate within families, the heritability of carotid artery intima-media thickness (IMT) is less well documented. We report IMT heritability estimates in Mexican American, Salvadoran American, or Guatemalan American (all referred to as Latino) families ascertained through a hypertensive proband. IMT and cardiovascular risk factors (age, sex, blood pressure, body mass index, lipids, fasting glucose, and insulin sensitivity) were measured in 204 adult offspring of 69 hypertensive probands, along with 82 parents (54 probands and 28 spouses). In the offspring, variance component analysis revealed a heritability for IMT of 64% (P< 0.0001) after adjustment for significant cardiovascular risk factors. Genetic factors accounted for 50% of the total variation in IMT, whereas significant cardiovascular risk factors explained 22% (14% were due to age). For offspring and parents combined, adjusted IMT heritability was less, 34% (P=0.0005), with genetic factors accounting for 18% of the total IMT variation, whereas significant cardiovascular risk factors explained 46% (38% were due to age). We conclude that variation in common carotid artery IMT is heritable in Latino families with a hypertensive proband. Heritability is particularly evident in younger family members, suggesting that acquired factors contribute progressively to IMT variability with aging.

Characterization of differentially expressed genes in purified Drosophila follicle cells: toward a general strategy for cell type-specific developmental analysis

Axis formation in Drosophila depends on correct patterning of the follicular epithelium and on signaling between the germ line and soma during oogenesis. We describe a method for identifying genes expressed in the follicle cells with potential roles in axis formation. Follicle cells are purified from whole ovaries by enzymatic digestion, filtration, and fluorescence-activated cell sorting (FACS). Two strategies are used to obtain complementary cell groups. In the first strategy, spatially restricted subpopulations are marked for FACS selection using a green fluorescent protein (GFP) reporter. In the second, cells are purified from animals mutant for the epidermal growth factor receptor ligand gurken (grk) and from their wild-type siblings. cDNA from these samples of spatially restricted or genetically mutant follicle cells is used in differential expression screens employing PCR-based differential display or hybridization to a cDNA microarray. Positives are confirmed by in situ hybridization to whole mounts. These methods are found to be capable of identifying both spatially restricted and grk-dependent transcripts. Results from our pilot screens include (i) the identification of a homologue of the immunophilin FKBP-12 with dorsal anterior expression in egg chambers, (ii) the discovery that the ecdysone-inducible nuclear hormone receptor gene E78 is regulated by grk during oogenesis and is required for proper dorsal appendage formation, and (iii) the identification of a Drosophila homologue of the human SET-binding factor gene SBF1 with elevated transcription in grk mutant egg chambers.

Photon beam skin dose analyses for different clinical setups

A comprehensive set of data on skin dose for 8 MV and 18 MV photon beams from a medical linear accelerator was measured using a parallel-plate chamber to document the effect of field size, source-to-surface distance (SSD), off-axis distance, acrylic block tray, wedge (external standard wedge), Lipowitz's metal block, multileaf collimator (MLC), and dynamic wedge. The skin dose increased as field size increased from 5 X 5 cm2 to 40 X 40 cm2 (6% to 38% for 8 MV and 5% to 44% for 18 MV beam). With the use of an acrylic block tray, the skin dose increased for all field sizes (7% to 59% for 8 MV and 5% to 62% for 18 MV beam), but the increase was minimal for small fields. The skin dose with a wedge showed a much more complex trend. It was generally lower than the dose for an open field, but higher in the case of large fields and higher degree wedges. When both wedge and block tray were used, the tray was a major contributor to the skin dose because some of the contaminant electrons from the wedge assembly were absorbed by the block tray. Field-shaping blocks increased the skin dose, but, interestingly, the block tray reduced the skin dose for small blocked fields treated with a high-energy photon beam. The effect of an MLC on skin dose was very similar to that of a Lipowitz's metal block, but its magnitude was less. The skin dose was higher for dynamic wedge fields than it was for standard wedge fields. As SSD decreased, the skin dose increased, and this effect was dominant in larger field sizes. The SSD effect was enhanced in the presence of an acrylic block tray. The skin dose off-axis was the same as at the central axis, or smaller. A similar pattern of behavior of the skin dose is expected for photon beams from other linear accelerators.

The role of carotid arterial intima-media thickness in predicting clinical coronary events

BACKGROUND

Carotid arterial intima-media thickness is used as a noninvasive surrogate end point to measure progression of atherosclerosis, but its relation to coronary events has not been fully explored.

OBJECTIVE

To determine whether carotid arterial intima-media thickness predicts coronary events.

DESIGN

Long-term follow-up (average, 8.8 years) of a previously assembled cohort of persons who completed the 2-year Cholesterol Lowering Atherosclerosis Study, a randomized arterial imaging trial designed to study the effects of lipid lowering on progression of atherosclerosis.

SETTING

University-based ultrasonography laboratory.

PATIENTS

146 men 40 to 59 years of age who had previously had coronary artery bypass graft surgery.

MEASUREMENTS

Preintrusive atherosclerosis in the common carotid artery was evaluated every 6 months with B-mode ultrasonography, and intrusive atherosclerosis in the coronary arteries was evaluated at baseline and at 2 years with quantitative coronary angiography. After the trial, the incidences of coronary events (nonfatal acute myocardial infarction, coronary death, and coronary artery revascularization) were documented.

RESULTS

For each 0.03-mm increase per year in carotid arterial intima-media thickness, the relative risk for nonfatal myocardial infarction or coronary death was 2.2 (95% CI, 1.4 to 3.6) and the relative risk for any coronary event was 3.1 (CI, 2.1 to 4.5) (P < 0.001). Absolute intima-media thickness was also related to risk for clinical coronary events (P < 0.02). Absolute thickness and progression in thickness predicted risk for coronary events beyond that predicted by coronary arterial measures of atherosclerosis and lipid measurements (P < 0.001).

CONCLUSION

Noninvasive B-mode ultrasonographic measurement of progression of intima-media thickness in the distal common carotid artery is a useful surrogate end point for clinical coronary events.

Performance evaluation of a diode array for enhanced dynamic wedge dosimetry

The performance of a diode array (Profiler) was evaluated by comparing its enhanced dynamic wedge (EDW) profiles measured at various depths with point measurements using a 0.03 cm3 ionization chamber on a commercial linear accelerator. The Profiler, which covers a 22.5 cm width, was used to measure larger field widths by concatenating three data sets into a larger field. An innovative wide-field calibration technique developed by the manufacturer of the device was used to calibrate the individual diode sensitivity, which can vary by more than 10%. Profiles of EDW measured with this device at several depths were used to construct isodose curves using the percentage depth dose curve measured by the ionization chamber. These isodose curves were used to check those generated by a commercial treatment planning system. The profiles measured with the diode array for both 8 and 18 MV photon beams agreed with those of the ionization chamber within a standard deviation of 0.4% in the field (defined as 80% of the field width) and within a maximum shift of less than 2 mm in the penumbra region. The percentage depth dose generally agreed to within 2% except in the buildup region. The Profiler was extremely useful as a quality assurance tool for EDW and as a dosimetry measurement device with tremendous savings in data acquisition time.

[Studies on characteristics of proliferation and differentiation of hematopoietic stem cells in mice]

By using Y chromosome specific sex-determining region (Sry) as a new cytogenetic marker and PCR technique, the characteristics of proliferation and differentiation of hematopoietic stem cells in mice were studied. Bone marrow cells from male mice were injected into lethally-irradiated female mice, PCR results indicated that all of the CFU-S were originated from donor. It was found that CFU-S was able to proliferate and differentiate into various hematopoietic cells in vivo during its transplantation. Whereas the fibroblasts within donor CFU-S and the fibroblasts from bone marrow in recipient mouse reestablished by donor CFU-S were shown to be originated from the recipient. The above data demonstrated that CFC-S from bone marrow in mice possessed the characteristics of hematopoietic stem cells but was not prone to differentiate into fibroblasts.

Effect of supplementary antioxidant vitamin intake on carotid arterial wall intima-media thickness in a controlled clinical trial of cholesterol lowering

BACKGROUND

There is accumulating experimental, epidemiological, and clinical evidence of an association between anti-oxidant vitamin intake and reduced risk of coronary heart disease. Using data from the Cholesterol Lowering Atherosclerosis Study (CLAS), we explored the association of self-selected supplementary antioxidant vitamin intake on the rate of progression of early preintrusive atherosclerosis.

METHODS AND RESULTS

CLAS was an arterial imaging trial in which nonsmoking 40- to 59-year-old men with previous coronary artery bypass graft surgery were randomized to colestipol/niacin plus diet or placebo plus diet. The rate of progression of early preintrusive atherosclerosis was determined in 146 subjects using high-resolution B-mode ultrasound quantification of the distal common carotid artery far wall intima-media thickness (IMT). From the nutritional supplement database, 22 subjects had an on-trial average supplementary vitamin E intake of > or = 100 IU per day (high users) and 29 subjects had an average on-trial supplementary vitamin C intake of > or = 250 mg per day (high users). Within the placebo group, less carotid IMT progression was found for high supplementary vitamin E users when compared with low vitamin E users (0.008 versus 0.023 mm/y, P = .03). No effect of vitamin E within the drug group was found. No effect of vitamin C within the drug or placebo group was found.

CONCLUSIONS

Supplementary vitamin E intake appears to be effective in reducing the progression of atherosclerosis in subjects not treated with lipid-lowering drugs while the process is still confined to the arterial wall (early preintrusive atherosclerosis).

Evaluation of computerized edge tracking for quantifying intima-media thickness of the common carotid artery from B-mode ultrasound images

A new method to measure carotid intima-media thickness (IMT) from B-mode ultrasound images was developed that utilizes automatic tracking of the lumen-intima and media-adventitia echoes. Phantom studies and human replicate studies under typical clinical protocols for common carotid IMT measurement were carried out to assist in evaluation of the method. A lucite step wedge phantom was used to show that incorporation of sub-pixel interpolation to locate echo boundaries allowed detection of changes in the echo separation that were 5-10 times smaller than the axial resolution of the ultrasound transducer. For average IMT measured in the distal common carotid artery (CCA) wall in 24 subjects scanned twice within 60 days, mean absolute difference was 0.036 mm with a standard deviation of 0.045 mm. Replicate scans obtained 1 week apart of eight subjects by three sonographers showed the intersonographer variability was 5.4%. In another study of 12 subjects scanned every 4 months for 48 months, the root mean square deviation of the IMT measurements from a linear regression line was 0.030 mm. These data indicate that the method is equally precise over short intervals (60 days) and over long intervals (48 months). The new automated computerized edge tracking method presented in this paper represents an advance for image analysis of B-mode ultrasound images of common carotid IMT with measurement variability substantially reduced (2 to 4 times) compared with currently available manual methods.

One-year reduction and longitudinal analysis of carotid intima-media thickness associated with colestipol/niacin therapy

BACKGROUND AND PURPOSE

The Cholesterol Lowering Atherosclerosis Study has reported significant reduction of coronary artery disease and of carotid arterial intima-media thickness (IMT) at 2 and 4 years with colestipol/niacin therapy. We now report on treatment effects on carotid IMT at 6 months and 1 year.

METHODS

One hundred eighty-eight nonsmoking men, aged 40 to 59 years, with prior coronary artery bypass graft surgery were randomized to colestipol/niacin plus diet therapy or placebo plus diet therapy. Computerized image processing of carotid ultrasound films was used to measure IMT in the right common carotid artery. Treatment group comparisons were made at 6 months and 1 year (46 and 33 subjects, respectively, with baseline and 6-month or 1-year ultrasound measures). The time course of the treatment effect on carotid IMT was estimated using the complete sample of 78 subjects with baseline and on-trial data.

RESULTS

No significant treatment group differences on carotid IMT were found at 6 months. At 1 year, the treated group showed significant reduction of carotid IMT (P = .01 between groups). The placebo group showed continuing progression of IMT during the 4-year study period (estimated progression rate, 0.018 mm/y). The treated group showed reduction of IMT during the first 3 years and a plateau during the remainder of the study.

CONCLUSIONS

Reduction of carotid IMT was found with aggressive lipid-lowering therapy. Ultrasound measures of IMT offer a noninvasive and precise measure of early carotid atherosclerosis that will decrease sample size requirements, potentially decrease dropout rates, and widen the study population of antiatherosclerotic clinical trials.

Beneficial effects of colestipol-niacin therapy on the common carotid artery. Two- and four-year reduction of intima-media thickness measured by ultrasound

BACKGROUND

Controlled clinical trials have reported treatment effects evaluated with serial imaging in coronary and femoral but not cervical arteries. The Cholesterol Lowering Atherosclerosis Study, a coronary, cervical, and femoral angiographic trial of colestipol plus niacin, included a pilot study of standardized carotid ultrasound imaging.

METHODS AND RESULTS

Seventy-eight subjects had ultrasound studies at baseline, 2, and 4 years. Twenty-four drug and 22 placebo subjects had carotid ultrasound images at baseline, 2, and 4 years with matching cervical angiograms. Computer image processing was applied to ultrasound images of common carotid (far wall) and cervical angiograms. Computer operators were blind to treatment group. Carotid ultrasound measurements were tested for treatment effects and compared with measurements of atherosclerosis in coronary and cervical angiograms. Drug subjects showed significant progressive reduction in carotid thickness at 2 (P = .0001) and 4 years (P = .0001); placebo subjects significantly increased wall thickness at 2 and 4 years. Reduced levels of apolipoprotein B and increased levels of high density lipoprotein cholesterol and apolipoprotein C-III were significant predictors of carotid wall thinning. Ultrasound-measured carotid intima-media thickness was correlated at baseline with visually read coronary angiographic stenosis and at 2 years with a robust computer measurement of mild carotid atherosclerosis.

CONCLUSIONS

Common carotid intima-media thickening can be reduced by colestipol-niacin treatment. Two-year image-processed carotid ultrasound trials can provide adequate power with 50 subjects per group to test for this treatment effect.

Modified thermal clearance technique for determination of blood flow during local hyperthermia

The thermal clearance method utilizes the rate of temperature decay after the applied power is turned off to estimate the local blood flow. A limitation of this method has been its inability to account for the contribution of thermal conduction to the rate of temperature decay. As a result, the blood flow is generally overestimated. A modification of the thermal clearance method is described in this paper which enables the conduction component to be determined. Profiles of the tissue temperature are obtained in three mutually orthogonal directions about the point where thermal clearance is measured. The Laplacian of the temperature is evaluated from these profiles by the method of finite differences. The tissue thermal conductivity is estimated from literature values. The greatest source of error is the uncertainty in the location of the washout point in each catheter. Strict thermometry requirements must be adopted to reduce the localization error to +/- 0.25 cm. The thermometry catheters should be orthogonal to within +/- 10 degrees and all three catheters should be in contact at the washout point. The methodology was tested in a phantom, studied by use of a computer model, and implemented in the clinic. The experimental error in the conduction component is typically 50%. The resulting error in the blood flow depends on the relative rates of energy removal by blood flow and thermal conduction. When perfusion is the dominant mode of energy removal, the resulting uncertainty in the blood flow is typically in the range 20-30%.

Deleted HTLV-I provirus in blood and cutaneous lesions of patients with mycosis fungoides

Mycosis fungoides, a rare form of cutaneous T cell leukemia/lymphoma, is suspected of having a viral etiology on the basis of certain similarities to adult T cell leukemia, which is associated with human T cell leukemia/lymphoma virus type I (HTLV-I) infection. Cell lines were established from peripheral blood mononuclear cells (PBMC) of an HTLV-I-seronegative patient with mycosis fungoides. DNA hybridization analysis revealed the presence of HTLV-I-related sequences with unusual restriction endonuclease sites. Sequence analysis of subcloned fragments demonstrated the presence of a monoclonally integrated provirus with a 5.5-kilobase deletion involving large regions of gag and env and all of pol. Additional evidence for the presence of deleted proviruses was found by polymerase chain reaction (PCR) amplification of DNA from cutaneous lesions of five other HTLV-I-seronegative patients. The findings suggest that HTLV-I infection may be involved in the etiology of at least certain cases of mycosis fungoides.

Very early aortic responses during atherosclerosis induction in rabbits: measurement by duplex ultrasound. I. Non-invasive study of aortic hyperresponsiveness to serotonin

We report the use of a non-invasive ultrasound method to visualize and measure changes in serotonin reactivity of the abdominal aorta during the early stages of atherosclerosis development. Studies were performed at 0, 4, 8, and 14 weeks in New Zealand white rabbits fed a diet enriched with 0.5% cholesterol. Change in systolic vessel diameter at each examination was compared with changes in rabbits fed a control diet or rabbits on a diet enriched with cholesterol plus a concentrated marine lipid. After 4 weeks on the diets, the abdominal aortae of rabbit fed the cholesterol-rich diet displayed an enhanced vasoconstriction to serotonin (P less than 0.01). The enhanced vasoconstriction was observed prior to visible morphologic changes, and progressed when restudied at succeeding examinations. Morphologic abnormalities became evident at 8 weeks in cholesterol-fed animals. Dietary supplementation with marine lipid, rich in polyunsaturated fatty acids, diminished the effect of the atherogenic diet on aortic vasoconstriction.

Clinical and serological features of human herpesvirus-6 infection in three adults

3 adult patients with serological evidence of human herpesvirus-6 (HHV-6) infection had mild, afebrile illnesses with nonspecific symptoms. In each case, the characteristic clinical feature was the presence of enlarged, bilateral, non-tender, anterior and posterior cervical nodes early in the illness which persisted for up to 3 months. HHV-6 IgG antibody reciprocal titres of 160 to 2560 were found during acute infection, and decreased to a titre of 10 in 1 patient 3 years later. IgM responses were detected at low reciprocal titres (10) in 2 patients and disappeared after several months.

B-cell lymphoproliferation and lymphomagenesis are associated with clonotypic intracellular terminal regions of the Epstein-Barr virus

We analyzed 17 B-cell lineages cloned from two patients with infectious mononucleosis and found that different B-cell lineages exhibited notable variation in the length of the fused Epstein-Barr virus (EBV) terminal region on intracellular EBV episomes. EBV termini in different B-cell clones from the same person differed by as many as 15 to 20 reiterations of the ca. 500-base-pair terminal repeat sequence. In contrast, analysis of seven B-cell lineages cloned from a patient with a fatal, oligoclonal lymphoma revealed that three of the cell clones had the same-sized EBV terminal region. These three clones had previously been shown, by immunoglobulin gene analysis, to be metastatic daughter cells descended from a common progenitor. Similarity of the EBV terminal regions in the three daughter clones suggested that EBV infected the progenitor cell before proliferation and metastasis. Individual, EBV-infected cells from a single individual showed sufficient heterogeneity in their EBV termini to allow use of terminal fragment size as a clonal marker in studies addressing the contribution of EBV to the clonal pathogenesis of tumors with which this virus has been associated.

Antibody responses to two Epstein-Barr virus nuclear antigens defined by gene transfer

By transfecting small fragments of Epstein-Barr virus (EBV) DNA into cells, we defined two nuclear antigens, termed M and K, and examined serum from 258 subjects for antibodies against these antigens. We hoped to learn whether such single-antigen systems would clarify the association of EBV with various diseases. Although reactivity to M antigen was found in only 14 per cent of healthy EBV-seropositive subjects, 90 per cent of Chinese and North African patients with nasopharyngeal carcinoma had antibody to M. Nearly all persons (96 per cent) who were EBV seropositive, as judged by their serologic reaction to a nuclear antigen encoded by the complete virus (EBNA), had a reaction to K antigen. However, serum samples from three patients with chronic active EBV infection did not react to K, even though the serum contained anti-M titers above 1:1000. Lymphoid cells from one such patient carried a normal gene for K and made K protein of correct size. Therefore, in this patient the absence of antibody to K had not resulted from a viral mutation that destroyed the K protein. These serologic studies show that some patients with chronic active EBV infection have an abnormal immune response to a specific viral gene product.

Stable expression in mouse cells of nuclear neoantigen after transfer of a 3.4-megadalton cloned fragment of Epstein-Barr virus DNA

All cells that harbor the Epstein-Barr virus (EBV) genome contain a neoantigen in the nucleus (EBNA). By transfection we located a segment of the genome that encodes or induces an antigen serologically related to EBNA. The responsible genes are found in the 3.4-megaldalton BamHI fragment K of EBV DNA, specifically in the left 1.9 megadaltons represented by HindIII fragment I1. Mouse LTK- cells were cotransformed with recombinant plasmids, containing the herpes simplex virus thymidine kinase gene and either EcoRI fragment B or BamHI fragment of K of EBV DNA. The TK+ cells surviving in selective medium were cloned. About 50% of the clones expressed the neoantigen in every nucleus. These mouse cells were used as antigens in immunofluorescence tests. Antibody to the nuclear antigen was found in 30 human sera known to contain antibody to EBNA; it was not detected in 18 sera that did not have antibody to EBNA. Mouse cells expressing EBNA as the result of acquisition of cloned EBV DNA fragments should prove useful in the characterization of the structure of this antigen and as reagents for the diagnosis of EBV infections.