Genomic Signature of Mismatch Repair Deficiency in Areca Nut-Related Oral Cancer

Areca nut (AN) chewing contributes to an increase of oral squamous cell carcinoma (OSCC) cases in South and Southeast Asia; however, genomic events underlying the carcinogenesis process of AN-related OSCC remain unclear. Here, we comprehensively describe the genomic and transcriptome alterations of 113 Chinese OSCC patients (89 AN related and 24 AN negative) by whole-exome sequencing and RNA sequencing, and we compared the genomic differences between AN-related and AN-negative samples by integrating sequencing data of 325 OSCC patients from The Cancer Genome Atlas database and 50 from a published Taiwanese study. We identified 11 significantly mutated genes for OSCC, including 4 novel ones (ATG2A, WEE1, DST, and TSC2), of which WEE1 and ATG2A mutated with significantly higher rates in AN-related samples (P = 0.04 and P = 0.003, respectively). Mutational signature analysis revealed that AN-related OSCCs were specially characterized by the genomic signature of mismatch repair deficiency (dMMR), which could also predict the prognosis status of AN-related OSCC. In addition, an elevated PD-L1 expression was also observed in both AN-related patients (P = 3.71 × 10^-11) and those with a high dMMR level (P = 1.99 × 10^-4). Further differential expression analysis and in vitro experiments confirmed the role of dMMR in the development of OSCC induced by AN exposure. Taken together, this study first revealed the molecular profiles and highlighted the role of dMMR in AN-related OSCC among the Chinese population and identified that AN-related OSCC may represent a potential cohort for effective anti-PD-1/L1 immunotherapy.

Preoperative adjuvant therapy for locally advanced and recurrent/metastatic gastrointestinal stromal tumors: a retrospective study

BACKGROUND

Preoperative imatinib mesylate therapy for gastrointestinal stromal tumors (GISTs) is controversial. This study aimed to explore the clinical efficacy and optimal duration of preoperative imatinib mesylate (IM) therapy in patients with locally advanced and recurrent/metastatic GISTs.

METHODS

We retrospectively examined patients who received preoperative imatinib mesylate therapy from January 2013 to December 2018 at Xiangya Hospital, Central South University and the Second Xiangya Hospital of Central South University, China. Clinical data, including the results of tests for mutations in KIT and PDGFR, findings from regularly conducted re-examinations, abdominal-enhanced computed tomography/magnetic resonance imaging data, responses to imatinib, progression-free survival, and overall cancer-specific survival, were recorded.

RESULTS

A total of 25 patients were enrolled in our study, including 18 with a locally advanced GIST and 7 with recurrent or metastatic GISTs. Their ages ranged from 22 to 70 years (M:F = 1.6:0.9), with a mean age of 50.48 ± 12.51 years. The tumor locations included the stomach (56.0%), rectum (16.0%), enterocoelic/retroperitoneal sites (12.0%), and the small intestine (12.0%). Based on testing for mutations in KIT and PDGFR, 22 patients received 400 mg/day KIT, and 3 patients received 600 mg/day PDGFR. The median duration of preoperative IM therapy was 8.96 ± 4.81 months, ranging from 3 to 26 months. According to the Choi criteria, 24 patients achieved a partial response (PR), and 1 patient had stable disease (SD). All patients underwent surgery after preoperative IM therapy, and no postoperative complications appeared. The 2-year PFS and 5-year PFS were 92% and 60%, respectively, and the total 5-year cancer-specific survival (CSS) was 92%.

CONCLUSION

Preoperative imatinib therapy is feasible for locally advanced and recurrent/metastatic GISTs and can effectively shrink the tumor size, allow organ sparing, and avoid extensive organ resection. Moreover, the optimal duration of preoperative IM therapy in patients with locally advanced and recurrent/metastatic GISTs was 8.96 ± 4.81 months, ranging from 3 to 26 months, and gastric GISTs had a better response to preoperative IM therapy than did non-gastric GISTs.

Neutron yield enhancement in laser-induced deuterium-deuterium fusion using a novel shaped target

Neutron yields have direct correlation with the energy of incident deuterons in experiments of laser deuterated target interaction [Roth et al., Phys. Rev. Lett. 110, 044802 (2013) and Higginson et al., Phys. Plasmas 18, 100703 (2011)], while deuterated plasma density is also an important parameter. Experiments at the Shenguang II laser facility have produced neutrons with energy of 2.45 MeV using d (d, n) He reaction. Deuterated foil target and K-shaped target were employed to study the influence of plasma density on neutron yields. Neutron yield generated by K-shaped target (nearly 10(6)) was two times higher than by foil target because the K-shaped target results in higher density plasma. Interferometry and multi hydro-dynamics simulation confirmed the importance of plasma density for enhancement of neutron yields.

Laparoscopic versus open right hemicolectomy for colon cancer: a meta-analysis

OBJECTIVE

This meta-analysis was designed to assess the feasibility and safety of laparoscopic right hemicolectomy for colon cancer.

RESEARCH DESIGN

A systematic search of the MEDLINE, EMBASE, and Cochrane databases identified 12 studies that met the inclusion criteria for data extraction. Publications that compared laparoscopic right hemicolectomy and open right hemicolectomy for treatment of colon cancer in the past 20 years were collected for review. The primary outcomes used for meta-analysis were operating time, blood loss, number of harvested lymph nodes, time to first flatus, postoperative hospital stay, postoperative complications, mortality, and rate of recurrence.

RESULTS

Twelve studies that included 1057 patients were examined. Of these patients, 475 and 582 had undergone laparoscopic right hemicolectomy and open right hemicolectomy, respectively. There were significant reductions in blood loss, time to first flatus, postoperative hospital stay, and rate of wound but a operating time for laparoscopic right hemicolectomy compared with open right hemicolectomy. Other outcome variables such as number of harvested lymph nodes, postoperative complications except wound infection, mortality, and rate of recurrence were not found to be statistically significant for either group.

CONCLUSIONS

Compared with open right hemicolectomy, laparoscopic right hemicolectomy has the advantages of minimal invasion, faster recovery, and a lower rate of wound infection, and it can achieve the same degree of radicality and short-term prognosis as open right hemicolectomy. The drawback is that the operative time is longer.

An integrated genome-wide approach to discover tumor-specific antigens as potential immunologic and clinical targets in cancer

Tumor-specific antigens (TSA) are central elements in the immune control of cancers. To systematically explore the TSA genome, we developed a computational technology called heterogeneous expression profile analysis (HEPA), which can identify genes relatively uniquely expressed in cancer cells in contrast to normal somatic tissues. Rating human genes by their HEPA score enriched for clinically useful TSA genes, nominating candidate targets whose tumor-specific expression was verified by reverse transcription PCR (RT-PCR). Coupled with HEPA, we designed a novel assay termed protein A/G-based reverse serological evaluation (PARSE) for quick detection of serum autoantibodies against an array of putative TSA genes. Remarkably, highly tumor-specific autoantibody responses against seven candidate targets were detected in 4% to 11% of patients, resulting in distinctive autoantibody signatures in lung and stomach cancers. Interrogation of a larger cohort of 149 patients and 123 healthy individuals validated the predictive value of the autoantibody signature for lung cancer. Together, our results establish an integrated technology to uncover a cancer-specific antigen genome offering a reservoir of novel immunologic and clinical targets.

Radiotherapy of unicentric mediastinal Castleman's disease

Castleman's disease is a slowly progressive and rare lymphoproliferative disorder. Here, we report a 55-year-old woman with superior mediastinal Castleman's disease being misdiagnosed for a long term. We found a 4.3 cm mass localized in the superior mediastinum accompanied with severe clinical symptoms. The patient underwent an exploratory laparotomy, but the mass failed to be totally excised. Pathologic examination revealed a mediastinal mass of Castleman's disease. After radiotherapy of 30 Gy by 15 fractions, the patient no longer presented previous symptoms. At 3 months after radiotherapy of 60 Gy by 30 fractions, Computed tomography of the chest showed significantly smaller mass, indicating partial remission. Upon a 10-month follow-up, the patient was alive and free of symptoms.

Spectrally peaked electron beams produced via surface guiding and acceleration in femtosecond laser-solid interactions

Highly collimated MeV electron beam guiding has been observed along the target surface following the interaction of bulk target irradiation by femtosecond laser pulses at relativistic intensities. The beam quality is shown to depend critically on the laser contrast: With a ns prepulse, the generated electron beam is well concentrated and intense, while a high laser contrast produces divergent electron beams. In the case of large preplasma scale lengths, tunable guiding and acceleration of the target surface electrons is achieved by changing the laser incident angle. By expanding the preplasma scale length to several hundred micrometers, we obtained MeV spectrum-peaked electron beams with a 100 pC per laser pulse and divergence angles of only 3°. This technique suggests a stable method of injection of elections into a variety of accelerator designs.

Gynecomastia during imatinib mesylate treatment for gastrointestinal stromal tumor: a rare adverse event

BACKGROUND

Imatinib mesylate has been the standard therapeutic treatment for chronic myeloid leukemia, advanced and metastatic gastrointestinal stromal tumor (GIST). It is well tolerated with mild adverse effects. Gynecomastia development during the course of treatment has been rarely reported.

METHODS

Ninety-eight patients with advanced or recurrent GIST were treated with imatinib mesylate. Among the fifty-seven male patients six developed gynecomastia during the treatment. The lesions were confirmed by sonography. Sex hormone levels were determined in six patients with and without the presence of gynecomastia respectively. The patients with gynecomatia were treated with tamoxifene and the sex hormones were assayed before and after tamoxifene treatment.

RESULTS

In patients with gynecomastia the lump underneath the bilateral nipples was 2.5 to 5 centimeters in diameter. Their serum free testosterone levels ranged between 356.61 and 574.60 ng/dl with a mean ± SD of 408.64 ± 82.06 ng/dl (95% CI 343.03~474.25 ng/dl), which is within the normal range. The level of serum estradiol was 42.89 ± 16.54 pg/ml (95% CI 29.66~56.12 pg/ml). Three patients had higher levels (43.79~71.21 pg/ml) and the others' were within normal range of 27.00~34.91 pg/ml. Six patients without the development of gynecomastia had normal free testosterone. One patient died because of large tumor burden. The sex hormones had no significant changes before and after tamoxifene treatment.(P > 0.05)

CONCLUSIONS

Testosterone levels were not decreased in the six GIST patients with gynecomastia. Three patients had increased serum estradiol level which suggests that imbalance of sex hormones may be the cause of gynecomastia during treatment with imatinib mesylate.

Sonographically guided transthoracic biopsy of peripheral lung and mediastinal lesions: role of contrast-enhanced sonography

OBJECTIVES

The purpose of this study was to assess the impact of contrast-enhanced sonography on sonographically guided transthoracic needle biopsy of lung lesions.

METHODS

A total of 121 patients underwent sonographically guided transthoracic needle cutting biopsy. Of the 121 patients, 62 (contrast-enhanced sonography group) underwent contrast-enhanced sonography before biopsy, and the information from contrast-enhanced sonography was used to optimize the biopsy procedure. The remaining 59 patients constituted the non-contrast-enhanced sonography group. The enhancement patterns and echogenicity were evaluated by the consensus of 2 sonographers. The diagnostic efficacy was compared between the contrast-enhanced and non-contrast-enhanced sonography groups.

RESULTS

The enhancement intensity and extent varied greatly among different thoracic lesions, and an anechoic area (necrosis) was revealed in 26 of 62 lesions (41.9%) lesions after administration of the contrast agent. The overall diagnostic accuracy of sonographically guided transthoracic biopsy in this study was 85.9% (104 of 121). In the contrast-enhanced sonography group, the initial biopsy led to correct diagnosis in 58 of 62 lesions (93.6%). In the non-contrast-enhanced sonography group, the initial biopsy led to correct diagnosis in 46 of 59 lesions (78.0%). The difference in the diagnostic accuracy between the contrast-enhanced and non-contrast-enhanced sonography groups was statistically significant (P < .05).

CONCLUSIONS

Contrast-enhanced sonography enables differentiation of viable from necrotic portions of thoracic lesions and has a positive impact on the diagnostic efficacy of sonographically guided transthoracic needle biopsy.

Meta-analysis of laparoscopy-assisted distal gastrectomy with D2 lymph node dissection for gastric cancer

BACKGROUND

To assess the value of laparoscopy-assisted distal gastrectomy with D2 dissection for treatment of gastric cancer.

METHODS

We collected studies that have compared laparoscopy-assisted distal gastrectomy (LADG) and open distal gastrectomy (ODG) with D2 dissection for treatment of gastric cancer in the past 15 years. Data of interest for LADG and ODG were subjected to meta-analysis using a fixed-effect and random-effect model.

RESULTS

We analyzed 8 studies that included 1,065 patients. There were significant differences in operating time, blood loss, time to first flatus and first eating, postoperative hospital stay, and postoperative complications between the LADG and ODG groups. Compared with the ODG group, blood loss and complications in the LADG group decreased, time to recovery of gastrointestinal function and hospitalization period were shorter, but operating time was longer. There were no significant differences in the number of harvested lymph nodes, mortality, and rate of recurrence between the groups.

CONCLUSIONS

Compared with ODG, LADG with D2 dissection has the advantages of minimal invasion, faster recovery, and fewer complications, and it can achieve the same degree of radicality and short-term prognosis as ODG. The drawbacks are that the operating time is slightly longer and long-term prognosis is not clear.

Telomerase-specific oncolytic virotherapy for human hepatocellular carcinoma

AIM: To evaluate the therapeutic efficiency of replicative adenovirus CNHK300 targeted in telomerase-positive hepatocellular carcinoma.

METHODS: CNHK300, ONYX-015 (55 kDa protein deleted adenovirus) and wtAd5 (wild type adenovirus 5) were compared, and virus proliferation assay, cell viability assay, Western blot and fluorescence microscopy were used to evaluate the proliferation and cytolysis selectivity of CNHK300.

RESULTS: The replicative multiples in Hep3B and HepGII after 48 h of CNHK300 proliferation were 40 625 and 65 326 fold, respectively, similar to that of wtAd5.. However, CNHK300 exhibited attenuated replicative ability in normal fibroblast cell line BJ. CNHK300 could lyse hepatocellular carcinoma cells at a low multiplicity of infection (MOI), but could not affect growth of normal cells even at a high MOI.

CONCLUSION: CNHK300 is a cancer-selective replication-competent adenovirus which can cause oncolysis of liver cancer cells as well as wtAd5 (wild type adenovirus 5), but had severely attenuated replicative and cytolytic ability in normal cells. This novel strategy of cancer treatment offers a promising treatment platform.

[Androgen receptor and SMRT]

OBJECTIVE

To explore the interaction between androgen receptor (AR) and silencing mediator for retinoid and thyroid hormone receptor (SMRT) and their interaction site. Methods We recombined and constructed AR, SMRT gene and gene fragments, in vitro translated 35S fusion proteins to investigate the relationship between AR and SMRT using transient transfection, mammalian two-hybrid test, GST pull-down assay, and indirect immunofluorescence staining. Results AR possessed an intrinsic transcriptional repression activity and AR interacted directly with SMRT. One interactive surface on AR was mapped to the ligand-binding domain (LBD), and the presence of DNA binding domain enhanced this interaction. The binding surface on SMRT was mapped to the carboxyl-terminal nuclear receptor interacting domain (ID), and mutation of the LXXXIXXXI/L corepressor motif within this domain interferred with the interaction.

CONCLUSION

LBD domain on the AR can interact with ID2 motif on the SMRT.

Intraurethral brachytherapy for prevention of recurrent urethral stricture after internal urethrotomy or transurethral resection of scar

BACKGROUND PURPOSE

Restricture after internal urethrotomy is the major limitation to the long-term success of the procedure. The objective of this study was to evaluate the effect of intraurethral brachytherapy after internal urethrotomy or transurethral scar resection on recurrent urethral stricture.

PATIENTS AND METHODS

From January 1998 to June 1999, catheter-based intraurethral brachytherapy with 192-iridium was performed in 17 patients with recurrent urethral stricture to prevent restricture after internal urethrotomy or transurethral resection of scar. The radiation was repeated within 3 days after surgery to reach a total dosage of 1000 to 1500 cGy.

RESULTS

During the follow-up (range 14-27 months; mean 20 months), two patients had dysuria, including one patient with an atonic detrusor muscle. The other patient needed self-dilation. Fifteen patients presented normal voiding. The stricture recurred 3 months later in only one patient, so the restricture rate is 7%. No significant complication was observed associated with brachytherapy during the follow-up.

CONCLUSION

Intraurethral brachytherapy after internal urethrotomy or transurethral resection of scar is a safe and effective treatment for recurrent urethral strictures.