Adverse events associated with device assisted hyoid and tongue base suspension for obstructive sleep apnea

PURPOSE

Hyoid and tongue base suspension may treat obstructive sleep apnea (OSA). This study summarizes device-related adverse events associated with the AIRvance and AIRLIFT systems used for hyoid and tongue base suspension.

MATERIALS AND METHODS

The U.S. Food and Drug Administration's Manufacturer and User Facility Device Experience (MAUDE) database was queried for reports describing adverse events associated with hyoid or tongue base suspension from January 2012 to December 2022.

RESULTS

77 adverse events were identified. When performed separately, adverse events were equally as common with hyoid suspension as with tongue base suspension. More complications occurred postoperatively (51 [66.2 %]) than intraoperatively (26 [33.8 %]). The most reported adverse events were infection (23 [29.9 %]), broken screw (15 [19.5 %]), pain or discomfort (10 [13.0 %]), suture rupture (8 [10.4 %]), and dislodged screw (7 [9.1 %]). 10 infections required drainage or debridement; 12 required device explantation.

CONCLUSIONS

The present study is the largest and most longitudinal review of adverse events associated with hyoid and tongue base suspension. Infection was the most common adverse event, and may require device explantation. While adverse events were most frequently attributed to device malfunction, broken screw, suture rupture, and broken needle were often attributed to operator error due to application of excessive force. Surgeon training to increase familiarity with hyoid and tongue base suspension may reduce adverse events caused by operator error. The MAUDE database is limited as a passive surveillance system. Standardized reporting may improve understanding of associated adverse events, enabling better informed comparisons between surgical treatment options for OSA.

Airway fires in otolaryngologic surgery: A database review

PURPOSE

An estimated 34 % of reported operating room fires involve the airway. Despite the inherent risks in otolaryngologic surgery, education regarding prevention and management of airway fires is limited in graduate medical training. One contributing factor is a lack of reporting of such rare events in our literature.

METHODS

The U.S. Food and Drug Administration's Manufacturer and User Facility Device Experience database was queried for reports of adverse events related to fires occurring during surgical procedures of the airway from January 1, 2010, to March 31, 2020.

RESULTS

3687 reports were identified and 49 unique reports of airway fire were included. Sustained fires were described in 16 (32.7 %) reports and 33 (67.3 %) described transient flares. 2 fires extended beyond the airway and 9 (18.4 %) were noted to have occurred at the start of the case. Fires were reported most commonly during tonsillectomy (n = 22 [44.9 %]), vocal fold excision (n = 5 [10.2 %]), and adenoidectomy (n = 4 [8.2 %]). 46 reports attributed flare initiation to a specific element of the fire triangle. 16 patient and 2 operator injuries were reported. Saline washing was utilized in 7 (14.3 %) cases overall. Patients were extubated immediately in 2 (12.5 %) of the 16 reports of sustained fires. 0 mortalities were reported.

CONCLUSION

Airway fires were reported in a variety of upper airway procedures performed regularly by otolaryngologists. The triggering factor that led to fire was identified as a spark or char in about half of the reported cases, and only 2 reports described immediate removal of the endotracheal tube.

Systematic Review of Recurrence Rates of Benign Vocal Fold Lesions Following Surgery

OBJECTIVES

Benign vocal fold lesions which include vocal fold nodules, polyps, cysts and other lesions often recur after surgery and require additional treatments. This systematic review of the current literature evaluated the effects of adjunctive therapies in addition to surgical resection on the recurrence rates of benign vocal fold lesions in adults.

STUDY DESIGN

Systematic review.

METHODS

A search using relevant keywords in electronic databases was conducted. Extracted data include author, year of publication, patient demographics, diagnostic approach, lesion type, surgical procedure, type of adjunctive therapy and the rates of recurrence. Descriptive statistics were performed on the collected data when appropriate.

RESULTS

Eleven articles were identified with a total of 1085 patients. The total 1101 lesions studied included 591 (53.7%) polyps, 125 (11.4%) nodules, 146 (13.3%) cysts, 184 (16.7%) pseudocysts, 19 (1.7%) midfold masses, 18 (1.6%) sulcus vocalis and 18 (1.6%) varices. Besides surgery, adjunctive therapies included voice therapy, steroid injection and reflux medication. There were 141 reported lesion recurrences, with an average recurrence rate of 13.0%. The recurrence rate in studies with adjunctive therapies was 7.14%, and in studies with no adjunctive therapies it was 24.44%.

CONCLUSIONS

Available evidence suggests that adjunctive therapies following surgery are associated with decreased lesion recurrence rates. However, due to differences in sample size, inconsistent reporting of lesion characteristics, heterogeneity of adjunctive therapies, variability in follow-up time across studies, and other factors, it is not possible to determine exactly which adjunctive therapies are of significant benefit and which lesion types may benefit the most.

Otolaryngology residency program websites in a socially distanced application cycle

OBJECTIVE

To provide an updated evaluation of otolaryngology residency program websites during a socially distanced application cycle. Criteria were selected to evaluate for level of comprehensiveness, new content accommodating a virtual interview cycle, and stated commitment to diversity and inclusion.

STUDY DESIGN

Review of otolaryngology residency program websites.

SETTING

Online websites between December 2020 and January 2021.

METHODS

Otolaryngology residency program websites were evaluated for selected criteria. Programs were categorized by geographic location, size, and Doximity rankings. Differences between groups were analyzed using Student's t-test and analysis of variance with a significance level of P < .05.

RESULTS

118 otolaryngology residency program websites contained a mean (SD) of 16.3 (4.7) of 31 criteria (52.6%). Fewer than one third included virtual/video tours of facilities or the surrounding area. Only 33% had a stated commitment to diversity and inclusion. There was no difference in number of criteria included when categorized by geographic location (P = .22). Larger programs (17.9 vs 14.5, P < .001) and programs ranked in the top 50 by Doximity (17.7 vs 15.2, P = .003) included a significantly greater number of criteria.

CONCLUSION

While the comprehensiveness of otolaryngology residency program websites has improved, considerable room for improvement remains. Programs should strive to maintain updated websites that highlight training opportunities, program culture, and commitment to diversity and inclusion. Programs also should consider prioritizing the development of new online resources that may be especially useful to applicants during a virtual interview cycle.

Tracheotomy in COVID-19 Patients: A Systematic Review and Meta-analysis of Weaning, Decannulation, and Survival

OBJECTIVES

A systematic review and meta-analysis was conducted to determine the cumulative incidences of decannulation and mechanical ventilation weaning in patients with coronavirus disease 2019 (COVID-19) who have undergone a tracheotomy. Weighted average mean times to tracheotomy, to decannulation, and to death were calculated from reported or approximated means.

DATA SOURCES

PubMed, SCOPUS, CINAHL, and the Cochrane library.

REVIEW METHODS

Studies were screened by 3 investigators independently. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were followed. Studies including patients with COVID-19 who underwent a tracheotomy were identified. Studies without reported mechanical ventilation weaning or decannulation were excluded. Data were pooled using a random-effects model.

RESULTS

After identifying 232 unique studies, 18 articles encompassing outcomes for 3234 patients were ultimately included for meta-analysis, with a weighted mean follow-up time of 28.6 ± 6.2 days after tracheotomy. Meta-analysis revealed that 55.0% of tracheotomized patients were weaned successfully from mechanical ventilation (95% CI, 47.4%-62.2%). Approximately 34.9% of patients were decannulated successfully, with a mean decannulation time of 18.6 ± 5.7 days after tracheotomy. The pooled mortality in tracheotomized patients with COVID-19 was 13.1%, with a mean time of death of 13.0 ± 4.0 days following tracheotomy.

CONCLUSION

At the current state of the coronavirus pandemic, over half of patients who have required tracheotomies are being weaned off of mechanical ventilation. While 13.1% patients have died prior to decannulation, over a third of all tracheotomized patients with COVID-19 reported in the literature have undergone successful decannulation.

The jaw-dropping costs of oral cavity cancer malpractice

BACKGROUND

Medical litigation is different than it was 20 years ago due to changes in health care. This study provides an updated analysis of oral cavity malpractice litigation from the past two decades (2000-2010 and 2011-2019).

METHODS

Verdict reviews from the Westlaw database were analyzed from January 2000 to August 2019. Data were collected and analyzed with the Statistical Package for the Social Sciences.

RESULTS

Sixty-five lawsuits were evaluated across 24 states. Failure to diagnose was the most common allegation in both decades. Adjusting for inflation, the average amount awarded from 2000 to 2010 was $1 721 068 and $3 925 504 from 2011 to 2019.

CONCLUSIONS

There has been a significant rise in allegations of failure to biopsy and failure to refer (p < 0.05). In addition, while award amounts appear different between decades, the difference is not statistically significant (p = 0.248). Education should focus on early diagnosis, biopsy, and referral to physicians who routinely care for this patient population.

Complications associated with tracheoesophageal voice prostheses from 2010 to 2020: A MAUDE study

PURPOSE

Tracheoesophageal puncture with voice prosthesis placement remains the gold standard for voice restoration following total laryngectomy, but may cause various complications. This study aims to summarize patient-related and device-related adverse events associated with tracheoesophageal puncture and voice prosthesis placement.

MATERIALS AND METHODS

The U.S. Food and Drug Administration's Manufacturer and User Facility Device Experience database was queried for reports of adverse events related to tracheoesophageal puncture with voice prosthesis placement from January 1, 2010, to April 30, 2020. Data were extracted from reports pertaining to tracheoesophageal prostheses.

RESULTS

Seventy-seven reports involving tracheoesophageal voice prostheses were identified, from which 111 adverse events were extracted. Of these, 58 (52.3%) were patient-related, while 53 (47.7%) were device-related. The most frequently reported patient-related adverse events were aspirated prosthesis (24 [41.4%]), foreign body during placement (11 [19.0%]), aspiration pneumonia (9 [15.5%]), and aspirated brush tip (8 [13.8%]). The most common device-related adverse events were detached brush tip (15 [28.3%]), leak (14 [26.4%]), and torn esophageal flange (11 [20.8%]).

CONCLUSIONS

While tracheoesophageal puncture with voice prosthesis placement has revolutionized voice rehabilitation following total laryngectomy, the procedure may be associated with adverse events both at the time of placement and later. Interventions aimed at improving both physician and patient education may help reduce adverse events attributed to improper use. Further research is needed to clarify optimal approaches to education.

Respiratory Function and Voice: The Role for Airflow Measures

OBJECTIVE

To clarify the relationship between voice and respiratory function, and to understand the role for airflow measures in the evaluation of voice patients.

METHODS

Literature searches of MEDLINE (Ovid) and Web of Science were performed on April 6, 2020, to include articles written in English that both discussed voice in relation to lower respiratory function and reported evaluation of airflow. Search strategies included the keywords voice, respiratory, airflow, and aerodynamic measures. Data were extracted from articles that met inclusion criteria.

RESULTS

Twenty studies were included for review. Fourteen (70%) studies evaluated at least 1 spirometric respiratory measure, including Forced Vital Capacity, Forced Expiratory Volume in 1 second, and Forced Expiratory Flow. Other measures assessed included mean flow rate, mean peak airflow, phonatory airflow, inspiratory airflow, expiratory airflow, and phonation quotient. Notably, four studies which included pulmonary function tests (PFTs) as part of voice evaluation discovered previously undiagnosed respiratory disease in their study populations.

CONCLUSION

This review confirms that respiratory function contributes significantly to voice and reveals that few studies have explored the role for airflow measures in clarifying this relationship. Including airflow measures such as PFTs in standard voice evaluation may allow recognition of underlying respiratory disease contributing to voice dysfunction. Further research is recommended to establish indications and diagnostic criteria for the use of PFTs in voice patients.

Surgical management and outcomes of accessory parotid gland neoplasms: A systematic review

OBJECTIVE

To evaluate surgical approaches and outcomes associated with accessory parotid gland neoplasms.

DATA SOURCES

MEDLINE, SCOPUS, and the Cochrane Central Register of Controlled Trials.

REVIEW METHODS

A systematic review in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) was performed. Studies were included if they reported surgical management and outcomes of patients with accessory parotid gland neoplasms.

RESULTS

After screening 3532 records, 15 studies were included with a total of 187 patients. Benign tumors consisted of 61.5% of cases. External open, transoral, and preauricular endoscopic approaches were used for 82.3%, 11.3%, and 6.5% of cases, respectively. Accessory lobe resection alone, concurrent with partial parotidectomy, and concurrent with total parotidectomy were used in 54.8%, 43.0%, and 2.2% of cases, respectively. Complication rates were similar between histology groups (7.8% benign vs. 8.3% malignant, p = 0.82). Accessory lobe resection with concurrent partial parotidectomy had the lowest overall complication rate (6.3%). Resections limited to the accessory lobe were found to have an overall complication rate of 8.7%.

CONCLUSION

The results offer an overview of the surgical management and complications for accessory parotid gland tumors. Overall surgical complication rates found in these case series may be lower for management of accessory gland tumors than rates available in the literature for tumors within the main parotid gland.

Adverse Events Associated With Laser Use in the Upper Airway

OBJECTIVE

Surgical lasers are used extensively in head and neck surgery. Laser use in the upper airway offers many advantages but also presents risks to patients and operators that are not reported comprehensively. This study aims to summarize device malfunctions, patient complications, and subsequent interventions related to laser use in the upper airway.

METHODS

The US Food and Drug Administration's Manufacturer and User Facility Device Experience database was queried for reports of surgical laser adverse events from January 2010 to March 2020. Data were extracted from reports pertaining to the upper airway.

RESULTS

Sixty-two reports involving upper airway laser use in an operating room were identified, from which 95 events were extracted. Of these, 40 (42.1%) were adverse events to patients, 2 (2.1%) adverse events to operators, and 53 (55.8%) device malfunctions. Dislodgement of laser fiber in the airway (23 [57.5%]), burn (8 [20%]), and scar (5 [12.5%]) were the most common adverse events to patients. Two incidents of eye exposure through unfiltered microscope lenses were the only adverse events to operators. Fiber break (26 [49.1%]) and flare (12 [22.6%]) were the most common device malfunctions.

DISCUSSION

Surgical lasers have demonstrated utility in head and neck surgery but are associated with risks. This study discusses adverse events and device malfunctions associated with airway laser surgery and emphasizes shortcomings in current reporting.

IMPLICATIONS FOR PRACTICE

Standardized reporting and multi-institutional research are needed to better understand adverse events related to surgical laser use and to allow accurate estimation of their prevalence.

The Prevalence of Olfactory and Gustatory Dysfunction in COVID-19 Patients: A Systematic Review and Meta-analysis

OBJECTIVE

To determine the pooled global prevalence of olfactory and gustatory dysfunction in patients with the 2019 novel coronavirus (COVID-19).

DATA SOURCES

Literature searches of PubMed, Embase, and Scopus were conducted on April 19, 2020, to include articles written in English that reported the prevalence of olfactory or gustatory dysfunction in COVID-19 patients.

REVIEW METHODS

Search strategies developed for each database contained keywords such as anosmia, dysgeusia, and COVID-19. Resulting articles were imported into a systematic review software and underwent screening. Data from articles that met inclusion criteria were extracted and analyzed. Meta-analysis using pooled prevalence estimates in a random-effects model were calculated.

RESULTS

Ten studies were analyzed for olfactory dysfunction (n = 1627), demonstrating 52.73% (95% CI, 29.64%-75.23%) prevalence among patients with COVID-19. Nine studies were analyzed for gustatory dysfunction (n = 1390), demonstrating 43.93% (95% CI, 20.46%-68.95%) prevalence. Subgroup analyses were conducted for studies evaluating olfactory dysfunction using nonvalidated and validated instruments and demonstrated 36.64% (95% CI, 18.31%-57.24%) and 86.60% (95% CI, 72.95%-95.95%) prevalence, respectively.

CONCLUSIONS

Olfactory and gustatory dysfunction are common symptoms in patients with COVID-19 and may represent early symptoms in the clinical course of infection. Increased awareness of this fact may encourage earlier diagnosis and treatment, as well as heighten vigilance for viral transmission. To our knowledge, this is the first meta-analysis to report on the prevalence of these symptoms in COVID-19 patients.

Small-Molecule Sigma1 Modulator Induces Autophagic Degradation of PD-L1

Emerging evidence suggests that Sigma1 (SIGMAR1, also known as sigma-1 receptor) is a unique ligand-regulated integral membrane scaffolding protein that contributes to cellular protein and lipid homeostasis. Previously, we demonstrated that some small-molecule modulators of Sigma1 alter endoplasmic reticulum (ER)-associated protein homeostasis pathways in cancer cells, including the unfolded protein response and autophagy. Programmed death-ligand 1 (PD-L1) is a type I integral membrane glycoprotein that is cotranslationally inserted into the ER and is processed and transported through the secretory pathway. Once at the surface of cancer cells, PD-L1 acts as a T-cell inhibitory checkpoint molecule and suppresses antitumor immunity. Here, we demonstrate that in Sigma1-expressing triple-negative breast and androgen-independent prostate cancer cells, PD-L1 protein levels were suppressed by RNAi knockdown of Sigma1 and by small-molecule inhibition of Sigma1. Sigma1-mediated action was confirmed by pharmacologic competition between Sigma1-selective inhibitor and activator ligands. When administered alone, the Sigma1 inhibitor decreased cell surface PD-L1 expression and suppressed functional interaction of PD-1 and PD-L1 in a coculture of T cells and cancer cells. Conversely, the Sigma1 activator increased PD-L1 cell surface expression, demonstrating the ability to positively and negatively modulate Sigma1 associated PD-L1 processing. We discovered that the Sigma1 inhibitor induced degradation of PD-L1 via autophagy, by a mechanism distinct from bulk macroautophagy or general ER stress-associated autophagy. Finally, the Sigma1 inhibitor suppressed IFNγ-induced PD-L1. Our data demonstrate that small-molecule Sigma1 modulators can be used to regulate PD-L1 in cancer cells and trigger its degradation by selective autophagy.Implications: Sigma1 modulators sequester and eliminate PD-L1 by autophagy, thus preventing functional PD-L1 expression at the cell surface. This posits Sigma1 modulators as novel therapeutic agents in PD-L1/PD-1 blockade strategies that regulate the tumor immune microenvironment.Visual Overview: http://mcr.aacrjournals.org/content/molcanres/16/2/243/F1.large.jpg Mol Cancer Res; 16(2); 243-55. ©2017 AACR.

Abstract 3202: Pharmacologic modulation of Sigma1 induces autophagic degradation of programmed death-ligand 1 in cancer cells

Emerging evidence suggests that Sigma1 (also known as sigma1 receptor) is a unique ligand-operated integral membrane chaperone or scaffolding protein that contributes to cellular protein homeostasis. Previously, we found that treatment of various cancer cell lines with some prototypic small molecule modulators of Sigma1 can engage endoplasmic reticulum (ER) associated protein homeostasis pathways including the unfolded protein response and autophagy. Programmed death-ligand 1 (PD-L1) is a type 1 integral membrane glycoprotein that is processed and transported through the ER and secretory pathway of tumor cells. PD-L1 expressed at the surface of tumor cells can act as a T-cell inhibitory checkpoint molecule that inactivates tumor infiltrating immune cells that express PD-1, its cognate receptor. Here, we show that Sigma1 physically associates with PD-L1. In triple negative breast and androgen-independent prostate cancer cells, PD-L1 protein levels are suppressed by both RNAi mediated knockdown of Sigma1 and pharmacological modulation of Sigma1. We observe decreased cell surface and intracellular levels of PD-L1 by flow cytometry and biochemical subcellular fractionation respectively, which corresponds with a dose-responsive decrease in functional PD-L1/PD-1 interaction in a co-culture of cancer cells and T-cells. Inhibitors of autophagy block this suppression of PD-L1 protein levels, suggesting PD-L1 is degraded away by autophagy after Sigma1 modulation. Through confocal microscopy, we show that Sigma1 modulation results in colocalization of PD-L1 and GFP-LC3, a marker of autophagosomes. From these conclusions, we hypothesize that autophagic degradation of nascent PD-L1 after Sigma1 modulation plays a key role in preventing the transport of functional PD-L1 to the plasma membrane. Together, these data demonstrate that Sigma1 modulators have the potential to act as novel therapeutic agents in PD-1/PD-L1 blockade strategies.

Citation Format: Christina M. Maher, Jeffrey D. Thomas, Charles G. Longen, Derick A. Haas, Halley M. Oyer, Jane Y. Tong, Felix J. Kim. Pharmacologic modulation of Sigma1 induces autophagic degradation of programmed death-ligand 1 in cancer cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3202. doi:10.1158/1538-7445.AM2017-3202

Abstract 3023: Cytoplasmic sequestration and autophagic degradation of ErbB receptors in HER2-driven cancer cells by small molecule Sigma1 modulators

Epidermal growth factor receptors (EGFR/ErbB) drive cell growth, survival, metastasis, and resistance in a range of cancers. Heterodimerization of ErbB1/EGFR, ErbB2/HER2, and ErbB3/HER3 drives aggressive tumor growth through hyperactivation of cancer cell survival and growth signaling pathways. The increased protein production required to sustain these activities renders cancer cells acutely dependent on support factors, such as chaperones and scaffolds, that maintain protein homeostasis. ErbB receptors are integral membrane proteins and as such are synthesized in and transported through the secretory pathway, which comprises the endoplasmic reticulum (ER), Golgi, and associated compartments and vesicles. Nascent ErbB receptors are stabilized and chaperoned through this pathway, in part, by heat shock protein 90 family members, HSP90 and GRP94. Sigma1 (also known as sigma1 receptor) is a unique integral membrane protein found primarily in the ER. Emerging lines of evidence suggest that Sigma1 may function as a chaperone or possibly a scaffolding protein. We find that the levels of Sigma1 protein are elevated and aberrantly distributed in HER2-amplified breast tumor biopsies compared to benign breast tissue. These data indicate that the status and potentially the physiological role of Sigma1 are altered in malignancy and that Sigma1 may be a valid drug target in the treatment of HER2-driven breast cancers. Previously, we discovered that certain selective small molecule modulators of Sigma1 could be used to induce the unfolded protein response (UPR) and autophagy in a panel of cancer cell lines. Here, we demonstrate that these responses to Sigma1 modulators can be exploited to alter the trafficking, stability, and thus signaling of ErbB receptors in cancer cells. In vivo, Sigma1 modulators suppress the growth of xenografted HER2-amplified breast tumors. In the tumors, as well as in vitro cell culture, ErbB1-3 all are eliminated in response to treatment with prototypic small molecule Sigma1 modulators. This corresponds with suppression of downstream PI3K/Akt signaling and with induction of UPR and autophagy. Using high resolution microscopy and organelle fractionation techniques, we confirmed that the Sigma1 modulators induce cytoplasmic sequestration and subsequent degradation of ErbB receptors in ubiquitin-enriched autophagosomes. This process is blocked by cotreatment with autolysosome inhibitor, bafilomycin A1, suggesting that autophagy is the primary mechanism of Sigma1 modulator induced ErbB receptor degradation. Altogether, these data suggest that Sigma1 is a unique, ligand-operated scaffolding protein that contributes to the trafficking and stability of ErbB receptors in HER2-driven cancer cells. Furthermore, these data suggest that Sigma1 is a druggable component of the protein homeostasis regulatory apparatus of cancer cells.

Citation Format: Christina M. Maher, Jane Y. Tong, Charles G. Longen, Mercedes I. Lioni, Jeffrey D. Thomas, Xing Tan, Logan Tyler, Fernando U. Garcia, Felix J. Kim. Cytoplasmic sequestration and autophagic degradation of ErbB receptors in HER2-driven cancer cells by small molecule Sigma1 modulators. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 3023.

Human chorionic gonadotropin-beta subunit gene expression in cultured human fetal and cancer cells of different types and origins

BACKGROUND

The authors' previous investigations using living cultured human cancer cells and cells isolated from cancer tissues, analytical flow cytometry, and monoclonal antibodies directed to epitopes located in five different sites of the human chorionic gonadotropin (hCG) molecule, identified the presence of membrane-associated hCG, its subunits and fragments, by cells from all cancers, irrespective of type and origin, indicating that the expression of these sialoglycoproteins is a common phenotypic characteristic of cancer. Although benign neoplasms do not express these compounds, cultured human embryonic and fetal cells also express the same materials. To corroborate these findings, five fetal cell lines and 28 cancer cell lines were randomly selected from those previously studied, to determine the presence of translatable levels of hCG-beta (hCG beta) mRNA.

METHODS

All cell lines were grown under identical conditions. Determination of hCG beta mRNA was made by extracting the total RNA from the cells, followed by synthesis of cDNA with RNase H- reverse transcriptase and polymerase chain reaction amplification using specific hCG beta-luteinizing hormone-beta (hLH beta) primers. The presence of amplified hCG beta cDNA was corroborated by hybridization of the product with an hCG beta-specific oligonucleotide and Southern blot analyses of the hybridization products. Gestational choriocarcinoma cells and HeLa adenocarcinoma of cervical cells, known producers of biologically active hCG, were positive control subjects, and human pituitary cells were used as negative control subjects.

RESULTS

The results showed single and multiple hCG beta gene activation by the fetal cells and the different types of cancer, indicating that at any given time, there is the possibility of activation of as many as four genes of the six genes of the hCG beta-hLH beta gene cluster, even though alternative gene splicing cannot be ruled out.

CONCLUSIONS

In addition to the authors' previous findings, the results of these studies support the concept that cancer is a problem of development and differentiation, and, to the authors' knowledge, prove definitively for the first time that synthesis and expression of hCG, its subunits, and its fragments, is a common biochemical denominator of cancer, providing the scientific basis for studies of its prevention and/or control by active and/or passive immunization against these sialoglycoproteins.

Immunological detection of membrane-associated human luteinizing hormone correlates with gene expression in cultured human cancer and fetal cells

We have demonstrated the expression of membrane-associated hCG and its subunits and fragments by cells from 78 human cancer cell lines of different types and origins, indicating that such expression is a common phenotypic characteristic of cultured human malignant cells. Because human (h) LH beta has 80% homology with hCG beta and is coded by one of the seven genes in the gene cluster located in chromosome 19, it was important to determine whether hLH and its beta-subunit are also expressed as membrane-associated proteins by cells from human cancer cell lines. Thus, 11 cancer cell lines of different types and origins were adapted to grow in serumless medium, with Nutridoma-HU or SP as serum substitute, and analyzed by flow cytometry using two monoclonal antibodies directed to different conformational epitopes of intact hLH and a monoclonal antibody reacting with an epitope of hLH beta-free. The cells were also analyzed simultaneously for the expression of hCG and its subunits and fragments. Determination of translatable levels of hLH beta and hCG beta messenger RNAs (mRNAs) was performed in cells from some of the cancer cell lines, including the JEG-3 choriocarcinoma cell line, and in cells from a human fetal lung cell line. The analytical flow cytometry studies showed that in addition to the expression of membrane-associated hCG in all of its forms, expression of membrane-associated intact (holo) hLH and its free beta-subunit occurred in every case. These findings were corroborated by the presence of translatable levels of hLH beta and hCG beta mRNAs in all of the cancer cell lines analyzed, indicating that the expression of these membrane-associated glycoproteins is a phenotypic characteristic of human cancer cells and that the activation of the hCG beta-hLH beta gene cluster is nonselective. The presence of translatable levels of hCG beta-hLH beta mRNAs in the cultured human fetal lung cells punctuates once more the in vivo and in vitro biochemical similarities between fetal and cancer cells.

Heteroduplexes for HLA DQB1 identity of family members and kidney donor-recipient pairs

DNA heteroduplex (HD) electrophoretic patterns of DQB1 alleles from 124 individuals (38 members from 7 families and 43 kidney donor-recipient pairs) were analyzed in reference to each individual's DQB1 diallelic types determined by the polymerase chain reaction-RFLP method. The assignment of DQB1 homozygosity and heterozygosity, based solely on HD patterns, was accurate and correlated well with the typing results. DQB1 homozygotes invariably gave HD patterns of a single band while heterozygotes gave HD patterns of multiple bands. Distinct HD patterns of 2 heterozygotes predict the presence of at least 1 different DQB1 type between the pair. However, pairs with identical HD patterns may have different subtypes, because HDs with 1 or 2 nucleotide differences may sometimes give an identical HD pattern. Because of its simplicity and reproducibility, this HD analysis protocol serves as an excellent alternative to screen for DQB1 homozygotes and mismatched tissue donor-recipient pairs. This protocol is also useful for confirming the correctness of DQB1 allelic type assignments in a clinical setting.

Molecular compatibility and renal graft survival--the HLA DRB1 genotyping

HLA DRB1 allelic types were determined by using sequence-specific oligonucleotides for the analysis of 91 renal donor-recipient pairs that were followed for 30 months. The Kaplan-Meier method was used to evaluate graft survivals (GS) of the matched and mismatched groups. The degree of compatibility was measured by allelic type matches and mismatches of the pairs. Furthermore, HLA DR genotypes were categorized into five groups, namely DR1, DR2, DR4, the group that also has the DRw52 allele, and the group of DR7, DR9, and DR10. All types within a group were considered a match. Serotypes of the same study group were also included for comparison. Associations of superior GS with compatible DRB1 allelic types, serotypes, and grouped DRB1 types were observed. A significantly higher GS rate was found in donor-recipient pairs when HLA DRB1 types were analyzed by group mismatching (P = 0.03) rather than type mismatching (P > 0.34). Because of the numerous allelic types that can be assigned on the basis of nucleotide sequence variations, a larger number of donor-recipient pairs is required to derive statistically significant results.

Molecular compatibility and renal graft survival--the HLA DQB1 genotyping

Renal donor-recipient HLA DQB1 typing at the DNA level provides a new avenue to study graft survival (GS) and compatibility. HLA DQB1 genotypes of 63 renal donor-recipient pairs were typed simultaneously by assessing patterns from electrophoresed restriction fragments (PCR-RFLP) of amplified DNA (ADNA) and hybridization patterns of sequence specific oligonucleotides (PCR-SSO) of ADNA. Thus the clinical applicability of these two protocols for HLA DQB1 typing was assessed in addition to the compatibility study. Typing results of these two protocols gave overall agreeable results. Sixty-seven per cent of 150 alleles from 75 heterozygotes typed by both protocols had identical allelic type assignments. Serotyping shared more concordant results to PCR-RFLP determined types than to PCR-SSO determined types. The PCR-RFLP protocol can be easily implemented for clinical DNA typing because of its clarity in assigning allelic types and the possible handling of a small number of typing samples, even a single sample, in a single run. The degree of compatibility of these donor-recipient pairs was measured by matching (M) or mismatching (MM) the PCR-RFLP determined DQB1 allelic types. The Kaplan-Meier method was used to estimate GS. Significantly higher GS rates (P < 0.03) were found in donor-recipient pairs with 2 M (GS:74%) as compared with those with 1 M (GS:68%) or 0 M (GS:40%). Higher graft survival was also associated with 0 MM (GS:86%) compared with those with 1 MM (GS:60%) or 2 MM (GS:40%), although the significance level is P = 0.08 for both Mantel-Cox and Breslow tests. These findings indicate the importance of determining HLA DQB1 molecular alleles for assessing GS.

Isolation and characterization of adenovirus type 12 E1 host-range mutants defective for growth in nontransformed human cells

In order to define the functions of human adenovirus type 12 (Ad12) early region 1 (E1) products in lytic infection and oncogenic transformation we have isolated and phenotypically characterized a set of host-range (hr) mutants of this serotype. These mutants grow efficiently upon HER3 cells, which contain and express type 12 E1 genes, but are restricted for growth upon A549 carcinoma and HeLa cells. Inter- and intratypic complementation analysis, marker-rescue mapping, and DNA sequence analysis have assigned some of the mutations to E1A sequence, and some to the reading frame encoding the E1B 54-kDa (482R) protein. Phenotypic analysis of the E1B mutants in particular has revealed some interesting, and in some cases surprising, findings relating to the roles of that protein in virus-cell interactions. This Ad12 gene product is required, either directly or indirectly, for efficient viral DNA replication in A549 and HeLa cells, unlike its counterpart in type 5 virus. Surprisingly, however, despite the severe defect in viral DNA replication, the synthesis of a few species of viral late proteins continues in cells infected by some of the E1B mutants. In contrast, none of these mutants brings about the inhibition of host-cell protein synthesis characteristic of wild-type virus infection, and with some E1B mutants no viral late proteins are made. Further, in a separate study reported elsewhere, we have demonstrated that the E1B 54-kDa product may also be involved, either directly or indirectly, in positive regulation of both E1A and E1B 19-kDa (163R) gene expression. The molecular and/or physiological bases for these various effects remain to be determined, but our initial results suggest that the E1B 54-kDa protein may carry out multiple regulatory functions during the viral life cycle.