Biomaterial-Based CRISPR/Cas9 Delivery Systems for Tumor Treatment

CRISPR/Cas9 gene editing technology is characterized by high specificity and efficiency, and has been applied to the treatment of human diseases, especially tumors involving multiple genetic modifications. However, the clinical application of CRISPR/Cas9 still faces some major challenges, the most urgent of which is the development of optimized delivery vectors. Biomaterials are currently the best choice for use in CRISPR/Cas9 delivery vectors owing to their tunability, biocompatibility, and efficiency. As research on biomaterial vectors continues to progress, hope for the application of the CRISPR/Cas9 system for clinical oncology therapy builds. In this review, we first detail the CRISPR/Cas9 system and its potential applications in tumor therapy. Then, we introduce the different delivery forms and compare the physical, viral, and non-viral vectors. In addition, we analyze the characteristics of different types of biomaterial vectors. We further review recent research progress in the use of biomaterials as vectors for CRISPR/Cas9 delivery to treat specific tumors. Finally, we summarize the shortcomings and prospects of biomaterial-based CRISPR/Cas9 delivery systems.

Pulmonary inhalation for disease treatment: Basic research and clinical translations

Pulmonary drug delivery has the advantages of being rapid, efficient, and well-targeted, with few systemic side effects. In addition, it is non-invasive and has good patient compliance, making it a highly promising drug delivery mode. However, there have been limited studies on drug delivery via pulmonary inhalation compared with oral and intravenous modes. This paper summarizes the basic research and clinical translation of pulmonary inhalation drug delivery for the treatment of diseases and provides insights into the latest advances in pulmonary drug delivery. The paper discusses the processing methods for pulmonary drug delivery, drug carriers (with a focus on various types of nanoparticles), delivery devices, and applications in pulmonary diseases and treatment of systemic diseases (e.g., COVID-19, inhaled vaccines, diagnosis of the diseases, and diabetes mellitus) with an updated summary of recent research advances. Furthermore, this paper describes the applications and recent progress in pulmonary drug delivery for lung diseases and expands the use of pulmonary drugs for other systemic diseases.

Preservation of superior laryngeal nerve in transoral surgery: A technology to enhance the recovery of swallowing function after surgery of hypopharyngeal carcinoma

OBJECTIVES

We intended to preserve the internal branch of superior laryngeal nerve in transoral surgery of hypopharyngeal squamous cell carcinoma and observe swallowing function recovery.

METHODS

26 patients with hypopharyngeal squamous cell carcinoma underwent transoral surgery with the preservation of internal branch of superior laryngeal nerve. Sensation in the pharyngolaryngeal mucosa was tested by flexible laryngoscope and swallow function was evaluated by water swallow test and MD Anderson Dysphagia Inventory questionnaire after surgery.

RESULTS

Surgeries were successfully performed in all patients. The internal branch of superior laryngeal nerve were preserved in all patients. Testing of mucosa sensation revealed the presence of the cough reflex in most patients. The water swallow test showed that 12 cases (46.15%) on the 1st day, 23 cases (88.46%) on the 7th day and 25 cases (96.15%) on the 14th day after operation had normal swallowing function. The mean score of MD Anderson Dysphagia Inventory was 98 on the 14th day after operation. All patients achieved an oral soft diet at a median of 3 days (range, 2-6 days), full normal oral diet at a median of 5.5 days (range, 4-10 days) and removal of the nasogastric tube at a median of 6 days (range, 5-11 days). During the two-year follow-up, 3 patients recured, 1 patient died of lung metastasis.

CONCLUSIONS

Preserving of the internal branch of superior laryngeal nerve in transoral surgery is feasible, and it can help to achieve a satisfactory recovery of the swallowing function after surgery of hypopharyngeal squamous cell carcinoma.

Flourishing tumor organoids: History, emerging technology, and application

Malignant tumors are one of the leading causes of death which impose an increasingly heavy burden on all countries. Therefore, the establishment of research models that closely resemble original tumor characteristics is crucial to further understanding the mechanisms of malignant tumor development, developing safer and more effective drugs, and formulating personalized treatment plans. Recently, organoids have been widely used in tumor research owing to their advantages including preserving the structure, heterogeneity, and cellular functions of the original tumor, together with the ease of manipulation. This review describes the history and characteristics of tumor organoids and the synergistic combination of three-dimensional (3D) culture approaches for tumor organoids with emerging technologies, including tissue-engineered cell scaffolds, microfluidic devices, 3D bioprinting, rotating wall vessels, and clustered regularly interspaced short palindromic repeats-CRISPR-associated protein 9 (CRISPR-Cas9). Additionally, the progress in research and the applications in basic and clinical research of tumor organoid models are summarized. This includes studies of the mechanism of tumor development, drug development and screening, precision medicine, immunotherapy, and simulation of the tumor microenvironment. Finally, the existing shortcomings of tumor organoids and possible future directions are discussed.

cdh23 affects congenital hearing loss through regulating purine metabolism

Introduction

The pathogenic gene CDH23 plays a pivotal role in tip links, which is indispensable for mechanoelectrical transduction in the hair cells. However, the underlying molecular mechanism and signal regulatory networks that influence deafness is still largely unknown.

Methods

In this study, a congenital deafness family, whole exome sequencing revealed a new mutation in the pathogenic gene CDH23, subsequently; the mutation has been validated using Sanger sequencing method. Then CRISPR/Cas9 technology was employed to knockout zebrafish cdh23 gene. Startle response experiment was used to compare with wide-type, the response to sound stimulation between wide-type and cdh23-/-. To further illustrate the molecular mechanisms underlying congenital deafness, comparative transcriptomic profiling and multiple bioinformatics analyses were performed.

Results

The YO-PRO-1 assay result showed that in cdh23 deficient embryos, the YO-PRO-1 signal in inner ear and lateral line neuromast hair cells were completely lost. Startle response experiment showed that compared with wide-type, the response to sound stimulation decreased significantly in cdh23 mutant larvae. Comparative transcriptomic showed that the candidate genes such as atp1b2b and myof could affect hearing by regulating ATP production and purine metabolism in a synergetic way with cdh23. RT-qPCR results further confirmed the transcriptomics results. Further compensatory experiment showed that ATP treated cdh23-/- embryos can partially recover the mutant phenotype.

Conclusion

In conclusion, our study may shed light on deciphering the principal mechanism and provide a potential therapeutic method for congenital hearing loss under the condition of CDH23 mutation.

[Application of supraclavicular fasciocutaneous island flap for reconstruction after removal of tumors in parotid and auricle area]

Objective: To evaluate the efficacy of supraclavicular fasciocutaneous island flap (SIF) for repairing the defect of parotid or auricle regions after tumor resection. Methods: From February 2019 to June 2021, 12 patients (11 males and 1 female, aged 54-77 years old), of whom 4 with parotid adenoid cystic carcinoma and 8 with auricular basal cell carcinoma underwent reconstruction surgery for postoperative defects in the parotid gland area and auricular area with SIF in the Department of Otorhinolaryngology Head and Neck Surgery, the Second Xiangya Hospital of Central South University and their clinical data were retrospectively analyzed. Size of the SIF, time for harvesting SIF, neck lymph node dissection and postoperative complications were recorded. Results: The flap areas were (6-9) cm × (8-13) cm, and the harvesting time for SIF ranged from 40 to 80 min, averaging 51.7 min. The donor sites were directly closed. All patients underwent ipsilateral levels Ⅰ-Ⅲ neck dissection, with 4 cases undergoing additional level Ⅳ neck dissection and 2 cases undergoing level Ⅳ-Ⅴ neck dissection. Of the 12 SIF, 10 were completely survival and 2 had flap arterial crisis with partial flap necrosis, in addition, 1 had donor site wound dehiscence. With follow-up of 10-42 months, there were no tumor recurrences in 10 patients, 1 patient was lost to follow-up at 10 months postoperatively, and 1 patient experienced local tumor recurrence at 11 months after surgery and died 15 months later. Conclusion: SIF is an easily harvested flap with good skin features matching the skin in parotid and auricle regions and less damage to donor site, and this flap has no need for microvascular anastomosis technique. SIF is feasible and effective for repairing defects in parotid and auricle area.

Functional acellular matrix for tissue repair

In view of their low immunogenicity, biomimetic internal environment, tissue- and organ-like physicochemical properties, and functionalization potential, decellularized extracellular matrix (dECM) materials attract considerable attention and are widely used in tissue engineering. This review describes the composition of extracellular matrices and their role in stem-cell differentiation, discusses the advantages and disadvantages of existing decellularization techniques, and presents methods for the functionalization and characterization of decellularized scaffolds. In addition, we discuss progress in the use of dECMs for cartilage, skin, nerve, and muscle repair and the transplantation or regeneration of different whole organs (e.g., kidneys, liver, uterus, lungs, and heart), summarize the shortcomings of using dECMs for tissue and organ repair after refunctionalization, and examine the corresponding future prospects. Thus, the present review helps to further systematize the application of functionalized dECMs in tissue/organ transplantation and keep researchers up to date on recent progress in dECM usage.

[Feasibility and efficacy of preserving internal branch of superior laryngeal nerve in endoscopic surgery for hypopharyngeal squamous cancer: an observational study]

Objective: This study was performed to investigate the feasibility of preservation of internal branch of superior laryngeal nerve(ibSLN) during transoral endoscopic surgery for hypopharyngeal squamous cancer(HSCC) and the influence on patient's swallowing function after operation. Methods: From May 2020 to June 2021, the data of 29 HSCC patients who required for transoral endoscopic surgery in the Department of Otorhinolaryngology Head and Neck Surgery, the Second Xiangya Hospital of Central South University were prospectively included, and the included patients were divided into two groups randomly by lottery. According to whether ibSLN was actively dissected during operation, they were divided into ibSLN preservation group (n=15) and control group (n=14, without ibSLN preservation). Operation time, intraoperative hemorrhage, intraoperative neck dissection, postoperative radiotherapy, postoperative recurrence within 1 year, retention and swallowing function, the recovery of oral soft diet and the quality of life were compared between two groups. SPSS 25.0 software was used for statistical analysis. Results: The study included 29 eligible patients, including 25 males and 4 females.The age ranged from 42 to 67 (56.07±5.93) years. There were no significant differences(P>0.05) between 2 groups in the following data,including age(t=-0.56), gender(χ2=0.01), TNM stage(T stageχ2=0.29, N stage χ2=0.02), pathological diagnosis(χ2=0.03), preoperative swallowing function(χ2=0.00) and M. D. Anderson Dysphagia Inventory(MDADI) score(global t=0.55, emotional t=0.16, functional t=0.60, physical t=0.64), operation time(t=1.62) and intraoperative hemorrhage(t=-1.46), intraoperative neck dissection(χ2=0.01), postoperative radiotherapy(χ2=0.32), postoperative recurrence within 1 year(P>0.050). The swallowing function was evaluated by water swallowing test after operation. The swallowing function of ibSLN preservation group was better than control group, and the difference between two groups was statistically significant on the 1st (χ2=4.44, P=0.035), 5th (χ2=4.24, P=0.039) and 7th (χ2=4.55, P=0.033) day after operation. On the 14th day after operation, the MDADI scores of patients in the ibSLN preservation group were higher than those in the control group in global (t=2.45, P=0.021), functional (t=2.54, P=0.017) and physical (t=2.24, P=0.034) dimensions, except for emotional dimension (t=1.89, P=0.070). The median time of oral soft diet(U=23.00, P<0.001), normal oral diet(U=21.00, P<0.001) and the nasogastric tube removal time (U=18.50, P<0.001) in ibSLN preservation group was 2 days, 5 days and 6 days respectively, earlier than that in control group, which had statistically significant difference. Conclusion: Our results show that it is feasible to preserve the ibSLN during HSCC transoral endoscopic surgery, which can achieve rapid recovery of postoperative swallowing function.

Biometrics-protected optical communication enabled by deep learning-enhanced triboelectric/photonic synergistic interface

Security is a prevailing concern in communication as conventional encryption methods are challenged by progressively powerful supercomputers. Here, we show that biometrics-protected optical communication can be constructed by synergizing triboelectric and nanophotonic technology. The synergy enables the loading of biometric information into the optical domain and the multiplexing of digital and biometric information at zero power consumption. The multiplexing process seals digital signals with a biometric envelope to avoid disrupting the original high-speed digital information and enhance the complexity of transmitted information. The system can perform demultiplexing, recover high-speed digital information, and implement deep learning to identify 15 users with around 95% accuracy, irrespective of biometric information data types (electrical, optical, or demultiplexed optical). Secure communication between users and the cloud is established after user identification for document exchange and smart home control. Through integrating triboelectric and photonics technology, our system provides a low-cost, easy-to-access, and ubiquitous solution for secure communication.

Anti-neutrophil cytoplasmic antibody-associated hypertrophic cranial pachymeningitis and otitis media: a review of literature

Background and objective

It has been recognized that anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides may lead to hypertrophic pachymeningitis (HP) or intractable otitis media (OM). To our knowledge, few cases of coexistent ANCA-related HP and OM have been described previously. To increase awareness of this disease, we reviewed the literature describing patients with HP and intractable OM in a population with AAV to guide clinical decision making for otolaryngologists.

Methods

 PubMed was searched with the following terms: ANCA-associated vasculitis, otitis media, and hypertrophic pachymeningitis. Only patients with concomitant AAV, OM and HP were considered and included in this review.

Results

A total of 243 articles were reviewed, and of these, 6 met inclusion criteria. Headache, cranial polyneuropathy, and intractable OM with effusion or granulation were common. Serum MPO–ANCA positivity was most common in Asian patients. Almost all patients had dural mater thickening on gadolinium-enhanced magnetic resonance imaging of the brain. Corticosteroids plus an immunosuppressant was more effective and most patients had improved hearing after treatment, but approximately 50% of subjects had disease relapse.

Conclusion

In this review, we summarized the current knowledge on the clinical features, diagnosis, treatment, and pathogenesis of this disease. We should carefully detect the potential cases of ANCA-related HP and OM in patients with intractable OM, HP, or AAV, and make the optimal treatment plan to avoid long-term neurological complications and irreversible hearing loss. Furthermore, due to an increased possibility of relapse, close follow-up, including a hearing test, ANCA titers, imaging examination, and detection of toxic and side effects of immunosuppressive therapy, are necessary.

Prevalence of mutations in GJB2, SLC26A4, and mtDNA in children with severe or profound sensorineural hearing loss in southwestern China

AIM

To study the distribution characteristics of common mutations in the GJB2, SLC26A4, and mtDNA genes in children with severe or profound sensorineural hearing loss (SNHL) in southwestern China.

MATERIALS AND METHODS

A total of 1,164 individuals were recruited to screen for the common GJB2, SLC26A4, and mtDNA mutations by microarrays. Subsequencing for the coding region of the GJB2 gene in the samples without the GJB2 hotspot mutations as well as subsequencing for the exon 1 of the TRMU gene in those samples with the mtDNA hotspot mutations was performed by Sanger sequencing. All mutations were analyzed in association with medical imaging.

RESULTS

In this study, 28.43% of all subjects carried mutations. The mutation frequencies in the GJB2, SLC26A4, and mtDNA genes were 17.27%, 7.04%, and 4.12%, respectively. No TRMU mutation was found in the study. The frequency of the mtDNA mutations in the multiethnic minorities was six times that in the Han (11.23% vs. 1.91%; p approaches 0.000) and in the urban group was one-third of that in the suburban group(1.49% vs. 4.47%; p=0.047). The frequency of the GJB2 mutations in urban and suburban groups was 23.38% and 15.99%, respectively (p=0.012). The enlarged vestibular aqueduct (EVA) was the most common inner ear malformation and ∼79.10% of EVA cases were associated with the SLC26A4 mutations.

CONCLUSIONS

More than one-fourth of children with severe or profound SNHL carried the common deafness mutations. The proportions of ethnic minorities and urban subjects could impact the frequency of the GJB2 and mtDNA mutations. The SLC26A4 hotspot mutations are prevalent and correlate strongly with EVA.

A rare disorder mimics otitis media: Langerhans cell histiocytosis of the temporal bone in a child with interstitial pulmonary fibrosis

Langerhans cell histiocytosis (LCH) is a rare disease ranging from a benign to a rapidly fatal condition affecting young children predominantly, and is characterized by an abnormal clonal proliferation of Langerhans cells. We report a case of a 3-year-old child presenting with a 1-year history of otorrhea and otorrhagia followed by a 6-month history of postauricular swelling in the right ear. Imaging demonstrated a large mass of organized tissue. A biopsy was conducted, and the diagnosis of LCH was confirmed by histopathological and immunohistochemical examination. The child was treated with a 12-month course of vinblastine chemotherapy with prednisolone. No clinical evidence of recurrence was noticed after 3 years of follow-up. This rare case highlights the importance for otolaryngologists to keep LCH in mind for differential diagnosis in very young patients with symptoms and signs suggestive of acute mastoiditis or chronic otitis media.

Whole-exome sequencing to decipher the genetic heterogeneity of hearing loss in a Chinese family with deaf by deaf mating

Inherited deafness has been shown to have high genetic heterogeneity. For many decades, linkage analysis and candidate gene approaches have been the main tools to elucidate the genetics of hearing loss. However, this associated study design is costly, time-consuming, and unsuitable for small families. This is mainly due to the inadequate numbers of available affected individuals, locus heterogeneity, and assortative mating. Exome sequencing has now become technically feasible and a cost-effective method for detection of disease variants underlying Mendelian disorders due to the recent advances in next-generation sequencing (NGS) technologies. In the present study, we have combined both the Deafness Gene Mutation Detection Array and exome sequencing to identify deafness causative variants in a large Chinese composite family with deaf by deaf mating. The simultaneous screening of the 9 common deafness mutations using the allele-specific PCR based universal array, resulted in the identification of the 1555A>G in the mitochondrial DNA (mtDNA) 12S rRNA in affected individuals in one branch of the family. We then subjected the mutation-negative cases to exome sequencing and identified novel causative variants in the MYH14 and WFS1 genes. This report confirms the effective use of a NGS technique to detect pathogenic mutations in affected individuals who were not candidates for classical genetic studies.

[Two cases of Castleman disease in the neck]

To investigate the clinical manifestation, clinicolpathological diagnosis and treatment of Castleman disease (CD) in the neck. The data of 2 patients with CD in the neck were reviewed retrospectively, together with literature summary, in order to analyze its clinical manifestation, pathological characteristics, clinical and pathological types, imaging characteristics and treatment. Two cases presented as solitary, painless neck masses and met the criteria of localized CD, and also had histological evidence of the hyaline vascular variant. Complete surgical resection was the first choice of treatment. One patient was alive without evidence of recurrence for ten years. The another patient had masses recurred in the neck one month after operation and followed to undergo curative chemotherapy, no recurrence in one-year follow-up. CD in the neck is a rare disease. The diagnosis for the disease is mainly based on pathological examination. Surgical resection is the main treatment, if necessary, need combination with radiotherapy and chemotherapy.

Study of clinical treatment of esophageal foreign body-induced esophageal perforation with lethal complications

Esophageal foreign body-induced esophageal perforation is a lethal complication and its treatment very complex. We had reviewed 1,428 patients with esophageal foreign body, who were hospitalized and treated over the past 25 years. A classification summary was made of 121 patients (of these 1,428 cases) who presented with esophageal foreign body-induced perforation and complicated cervical abscess, mediastinitis, and mediastinal abscess. This summary considered foreign body types, location and lodging duration, complications, and surgical approaches. Among these 121 patients, esophageal foreign bodies in 81 patients were successfully extracted via esophagoscope or fiber optic esophagoscope. Cervical esophageal foreign bodies in 22 patients were extracted by esophagoscope and lateral cervical incision (n = 6) and simple lateral cervical incision (n = 16). Thoracotomy was performed to remove thoracic esophageal foreign bodies in 18 patients with 10 successes and 8 failures. Of the 121 patients, 67 patients with cervical abscess were cured by means of lateral cervical abscess incision and drainage, esophageal stent placement, and esophageal perforation repair with pedicle myolemma or pedicle muscular periosteum flap. 54 patients with mediastinitis and/or abscess were all cured, except one mortality, by means of mediastinotomy and drainage or/and closed-chest drainage, simple esophageal repair, esophageal repair with pedicle myolemma or pedicle muscular periosteum flap and stent placement for esophageal perforation, and esophageal exclusion plus two-stage gastric-pharyngeal anastomosis. In the treatment of esophageal foreign body-induced severe complications, various therapies should be applied simultaneously. Lateral cervical incision should be made immediately to remove the foreign bodies if the foreign body extraction under esophagoscope proves to be a failure after repeated attempts, or esophageal perforation develops during the procedure, or should cervical abscess develop. Mediastinotomy and drainage or/and closed-chest drainage should be carried out as early as possible when mediastinitis and/or mediastinal abscess develops after esophageal foreign body ingestion.

Impaired membrane targeting and aberrant cellular localization of human Cx26 mutants associated with inherited recessive hearing loss

CONCLUSION

This study demonstrated that five Cx26 mutations (R32H, S199F, 572delT, 631-632delGT, and Y155X) affect gap junction (GJ) functions by causing impaired membrane targeting and aberrant cellular localization, and one mutation (R165W) leads to a constriction of the channel pore with no dye coupling.

OBJECTIVE

To investigate the pathogenetic roles of six recessive Cx26 mutations (p.R32H, p.R165W, p.S199F, c.572delT, c.631-632delGT, and p.Y155X), which have not been functionally analyzed in vitro.

METHODS

The six mutants and wild-type Cx26 (wtCx26) were cloned into the EcoRI and SalI sites of pEGFP-N1 vector. We transfected the seven constructs into HeLa cells, followed by analysis of their protein expression using the western blot method, study of the protein localizations and gap junction-plaques on the cytomembrane under confocal microscopy, and assessment of the dye coupling of the mutated GJ channels by intercellular dye transfer experiment.

RESULTS

p.R165W targeted the cytomembrane and formed GJ-like structures in adjacent HeLa cells, causing null dye coupling. The mutants (p.R32H, p.S199F, c.572delT, c.631-632delGT, and p.Y155X) failed to reach the cell surface, and perfectly co-localized with endoplasmic reticulum (ER) throughout the cells.

Study on the treatment of traumatic orbital apex syndrome by nasal endoscopic surgery

Orbital apex syndrome (OAS) is a complex disease caused by a variety of pathological factors, and trauma is one of the main factors/causes. Clinical data of 17 cases of traumatic OAS treated by nasal endoscopic surgery in our department from January 2002 to April 2009 were gathered and reviewed. Among them, the six patients presented with OAS after injury to the lateral wall of orbital apex. Seven other patients exhibited OAS after injury to the medial wall of orbital apex, two displayed OAS after zygomatic trauma, while OAS manifested in the other two patients with craniocerebral trauma 3 days after they had decompressive craniotomy--of them, one was blind in both eyes. In the 17 cases, 6 patients were without light sensation, 1 was blind in both eyes; the sight-chart index of eight patients was 0.1, that of three other patients was 0.1-0.2. Fifteen patients displayed eyeball movement disturbance (disorder) and cornea sensory disturbance (disorder), two were with the eyeball abducent disturbance. After the nasal endoscopic surgeries for OAS performed on the 17, the sight of the most patients was restored in varying degrees. The sight of nine patients was between 0.2 and 0.3, that of two patients was between 0.1 and 0.2, that of the other two patients was 0.1, and that of four patients remained unchanged. The eyeball movement and the cornea esthesia in 15 patients recovered from the surgeries, one patient recovered with good eyeball adducent movement and the cornea esthesia but with eyeball abducent disturbance, the other patient did not make a recovery from the eyeball immobility, cornea anesthesia and ptosis. A follow-up lasting 2 months to 2 years suggested that the 16 patients had stable recovery from the surgeries. Satisfactory results could be achieved in the treatment of traumatic OAS by nasal endoscopic surgery. From objective assessment of the therapeutic effects of traumatic OAS, it can be concluded that if a patient is diagnosed with fractures of the optic canal and the superior and medial walls of orbital apex, nasal endoscopic decompression of superior and medial walls of orbital apex and optic canal via the approach to the sphenoid and ethmoid sinuses is the most ideal operative therapy.

[The expressions and clinical significance of tumor suppressor gene CX26 in laryngeal squamous cell carcinoma]

OBJECTIVE

To investigate the expressions of tumor suppressor gene CX26 mRNA and coding protein in laryngeal squamous cell carcinoma, and to explore the relationship between CX26 gene and the biological behaviors of laryngeal squamous cell carcinoma for understanding the tumorigenicity and development of laryngeal squamous cell carcinoma.

METHOD

Laryngeal carcinoma tissues (studying group), which takeda from the center of tumors and laryngeal normal tissues (control group) takeda at the place of 1.0 cm out of the edge of the tumors, were took from 38 patients with laryngeal squamous cell carcinoma while they were in operation. Semi-quantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to analyze the expression level of CX26 mRNA, and immunohistochemical staining (frozen section) was used to detect the expression of CX26 protein in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases, respectively.

RESULT

mRNA of CX26 gene was all positively expressed in laryngeal carcinoma tissues and laryngeal normal tissues of 38 cases by RT-PCR. However, CX26 mRNA was obviously down-regulated in laryngeal carcinoma tissues than that in laryngeal normal tissues (P < 0.05). Immunohistochemical staining showed CX26 protein was strong-positively expressed in laryngeal normal tissues in 34 cases (89.5%), while it was positively expressed in laryngeal carcinoma tissues in 18 cases (47.4%), and with the location alteration of CX26 protein in laryngeal carcinoma cells. There was significant difference between the expression rate of CX26 protein in laryngeal carcinoma tissues and in laryngeal normal tissues (P < 0.05). Meanwhile, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein of the laryngeal carcinoma tissues in the advanced stage patients group (III stage and IV stage) were significantly lower than these in the early stage patients group (I and II) (P < 0.05), and it was significantly lower in those who have a cervical lymph node metastasis than those without metastasis. (P < 0.05). Moreover, the expression level of CX26 mRNA and the positive-expressed rate of CX26 protein reduced along with the reduction of pathological differentiation, and there was significant difference among the well-differentiated group, moderately-differentiated group and poorly-differentiated group (P < 0.05).

CONCLUSION

CX26 gene may play an important role in the pathogenesis and development of laryngeal carcinoma and may be related to its prognosis.

[Clinical analysis of extramedullary plasmacytomas in the head and neck]

OBJECTIVE

To summarize the clinical features and the experiences of diagnosis and treatment of extramedullary plasmacytomas (EMPs), and to enhance the cure rates of EMPs.

METHOD

Clinical data of 8 patients with EMPs in head and neck, who treated in our hospital from Jan. 1990 to Dec. 2004, were reviewed. Of 8 cases, 3 cases with the tumors occurred in nasal cavities, 1 in maxillary sinus, 2 in nasopharynx, 1 in posterior wall of oropharynx.

RESULT

Eight patients who were all pathologic confirmed EMP accepted surgical resections of the tumors, and 4 of 8 cases were boosted radiation therapy post-operation. Four cases were still alive disease-free for more than 1, 5, 10 and 12 years after treatments, respectively. One died of local recurrence in 2 years, 1 died of multiple myeloma in 3 year, and 1 died of heart attack in 2 years after treatments, respectively. One lost follow-up.

CONCLUSION

EMPs in head and neck are low potential malignancy tumors. The diagnosis of EMPs mainly depends on clinical manifestations and pathological results. Surgery and radiation therapy are the main treatments for EMPs in head and neck.

[Reconstructive methods for hypopharynx and cervical esophagus]

OBJECTIVE

To review the surgical treatment for reconstructing hypopharynx and cervical esophagus after hypopharyngo-oesophagectomy, and to evalue its efficacy.

METHODS

Different methods were adopted to reconstruct the hypopharynx and cervical esophagus among 25 cases, including 14 cases of carcinoma of the hypopharynx and 11 of carcinoma of hypopharynx and cervical esophagus. In accordance with the standard of the International Union Against Cancer in 1997, the 25 cases were divided into different clinic stages, among which 5 were in T(2)N(0), 2 in T(2)N(1), 4 in T(3)N(0), 3 in T(3)N(1), 7 in T(4)N(1) and 3 in T(4)N(2). Treatment protocol was as follow: Pure operation for 5 cases, re-operation after radiotherapy for 2 cases, operation plus radiotherapy for 18 cases, laryngeal conservation operation for 8, and neck dissection for 21 cases. Reconstruction was done by using free jejunal transplantation, gastric pull-up, the laryngotracheal flap, and myocutaneous flap.

RESULTS

After the reconstruction, 3 cases of free jejunal graft and gastric pull-up, 4 of laryngotracheal flap recovered oral fleeding within 2 weeks. No serious complications occurred. After 18 cases underwent the myocutaneous flap reconstruction, no complications occurred in 10 patients, but there were different complications in 8 cases, including pharyngocutaneous fistula (6 cases), haryngoesphageal stenosis (7 cases), and pectoralis major myocutaneous flap necrotic (1 case). The 3-year survival rate was 38.9% (7/18).

CONCLUSION

Reconstruction with free jejunal graft, gastric pull-up, and laryngotracheal flap constitutes is a safe and reliable method to restore the continuity of the upper digestive tract after pharyngo-laryngo-oesophagectomy. After the reconstruction with myocutaneous flap, there is high incidence of pharyngocutaneous fistula and haryngoesophageal stenosis.

[Functional interaction of the C-terminal of Nogo protein with connexin 26 and the expression of Nogo's mRNA in the murine inner ear]

OBJECTIVE

To screen and identify the proteins that interact with connexin 26 (CX26) and to analyze the expressions of these proteins in cochlea so as to explore the proteins that relate to the trafficking, assembly, localizing and gap junction functions of CX26.

METHODS

The whole coding region of GJB2 (CX26) gene was amplified from normal human genomic DNA by polymerase chain reaction (PCR) and then directionally subcloned into the vector pGBKT7 plasmid of the Match Maker Ga14 Two-Hybrid System 3 as a target to screen the interactive proteins of CX26 from the human fetal brain cDNA library by the yeast two hybrid technique. The false positive clones were discarded from the preys by repeated yeast two hybrid method between CX26 and everyone of the preys respectively. The DNAs of the insert of the identified positive clone were sequenced and BLAST analyzed against the GenBank. Lastly, the mRNA of the gene encoding the identified protein was analyzed in the murine inner ear by reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

The insert of one positive clone contained 867 bp with the former 525 bp being coding region. The DNA sequence and the open reading frame of the insert were identical to the 525 bp before the stop codes (including the stop codes) and the 238 bp after the stop codes of RTN4 gene which encoded Nogo protein. And the 174 amino acid residues encoded by the insert were those of the C-terminal of Nogo protein: Nogo-A, Nogo-B and Nogo-C. RTN4 mRNA expressed in the murine inner ear was confirmed by RT-PCR method.

CONCLUSION

The C-terminal of Nogo protein interacts with CX26. Nogo protein expresses in the inner ear and may take part in the trafficking of CX26 or CX26 gap junction function.

GJB2 (Cx26) gene mutations in Chinese patients with congenital sensorineural deafness and a report of one novel mutation

BACKGROUND

Mutations in GJB2 gene are a major cause of autosomal recessive congenital hearing loss and the cause in some rare cases of the autosomal dominant form. The purpose of this study was to investigate the frequency and the features of GJB2 mutations in the Chinese patients with congenital sensorineural deafness.

METHODS

Using PCR amplifying the entire coding region of GJB2 gene and direct DNA sequencing to analyze mutations in this gene among unrelated 69 cases with autosomal recessive congenital nonsyndromic deafness and 27 cases of dominant congenital deafness and 35 sporadic cases. We also detected mutations in GJB2 in 100 control subjects with normal hearing.

RESULTS

17.4% (12/69) of the probands in the autosomal recessive, 7.4% (2/27) of dominant families and 5.7% (2/35) of the sporadic congenital deafness patients had deafness-causing mutations in GJB2, respectively. Nine types of the mutations in GJB2 were detected in the recessive and sporadic group. They consisted of five types of polymorphism, and four types of deafness-causing mutation with homozygous 35delG in 1 sporadic (1/35), and 235delC frameshift mutation in 1 sporadic (homozygotes) and 10 recessive patients (2 heterozygotes and 8 homozygotes), and homozygous 442G-->A missense mutation and homozygous 465T-->A nonsense mutation in 1 different recessive proband, respectively. The 465T-->A that related to recessive deafness was a novel mutation found by this study. The homozygous (10/69, 14.5%) and the heterozygous (2/69, 2.9%) GJB2 mutation in the recessive patients (12/69, 17.4%) and the homozygotes in the sporadic patient (2/35, 5.7%) all had congenital severe to profound sensorineural hearing loss. 511G-->A missense mutation and 299-300delAT frameshift mutation were found in two autosomal dominant congenital deafness families (2/27, 7.4%). The total mutation frequency of GJB2 was 12.2% (16/131) in the Chinese patients with congenital sensorineural deafness and 235delC was the most common deafness-causing mutation. Six types of mutation-5 types of polymorphism and 1 type of heterozygous deletion (235delC) mutation were found in the 100 control subjects. The carry rate of the most frequent type of mutation 235delC was 0.5% in the controls (1/200 alleles). 109G-->A was the most frequent (15/100, 15%) and 79G-->A was the second common (8/100, 8%) polymorphism in this population.

CONCLUSIONS

The general mutation rate of GJB2 is 12.2% (16/131) and the 235delC is the most common type of deafness-causing mutation in Chinese patients with congenital hearing loss. 465T-->A nonsense mutation that is associated to autosomal recessive deafness is a novel mutation found by this screening. 511G-->A and 299-300delAT mutations contribute to autosomal dominant hearing loss. The study further supports the view that the common types of mutation in GJB2 according to different ethnic background and that the mutation prevalence in the East Asian deafness population is lower than that in the white population.

[Mutation screening in selected exons of myosin 7a gene in prelingual non-syndromic hearing impairment patients]

OBJECTIVE

To ascertain the frequency and characteristics of myosin 7a gene mutations in Chinese with prelingual nonsyndromic hearing impairment.

METHODS

Most of cases were collected within Hunan province, including 31 sporadic congenital deaf patients and 65 patients from 34 hereditary prelingual deafness families, and 100 health individuals were used as control. Genomic DNA was extracted from the patients and subjected to the PCR to amplify selected exons of myosin 7a gene, and then the amplified products were screened for base variations by single strand conformational polymorphismanalysis (SSCP). The bands with abnormal conformation were sequenced to confirm the mutation.

RESULTS

G to A substitution was detected at nucleotide 617 in exon 7 as hetrozygous state in two patients and was not found in unaffected members in their family. This mutation caused Arg206Gln within a highly conserved heptapeptide sequence of myosin 7a protein, and was close relevant to the prelingual nonsyndromic deafness.

CONCLUSIONS

The Arg206Gln mutation in exon 7 of myosin 7a is possibly a novel mutation to cause prelingual nonsyndromic hearing impairment. Our results provide the evidence that exon 7 of Myosin 7a is a mutational hotspot region in genetic deafness.