Unilateral post-chemotherapy robot-assisted retroperitoneal lymph node dissection in Stage II non-seminomatous germ cell tumor:A tertiary care experience

Objective Post-chemotherapy retroperitoneal lymph node dissection(PC-RPLND)represents an integral component of the management of patients with non-seminomatous germ cell tumor(NSGCT).Modified templates have been proposed to minimize the surgical morbidity of the procedure.Moreover,the implementation of robotic surgery in this setting has been explored.We report our experience with unilateral post-chemotherapy robot-assisted retroperitoneal lymph node dissection(PC-rRPLND)for clinical Stages IIA and IIB NSGCTs.Methods A retrospective single institution review was performed including 33 patients undergoing PC-rRPLND for Stages IIA and IIB NSGCTs between January 2015 and February 2019.Following orchiectomy,patients were scheduled for chemotherapy with three cycles of bleomycin-etoposide-cisplatin.Patients with a residual tumor of<5 cm and an ipsilateral metastatic disease on pre-and post-chemotherapy CT scans were eligible for a unilateral template in absence of rising tumor markers.Descriptive statistics were provided for demographics,clinical characteristics,intraoperative and postoperative parameters.Perioperative,oncological,and functional outcomes were recorded.Results Overall,7(21.2%)patients exhibited necrosis or fibrosis;14(42.4%)had mature teratoma;and 12(36.4%)had viable tumor at final histology.The median lymph node size at surgery was 25(interquartile range[IQR]21-36)mm.Median operative time was 180(IQR 165-215)min and no major postoperative complications were observed.Anterograde ejaculation was preserved in 75.8%of patients.Median follow-up was 26(IQR 19-30)months and a total of three recurrences were recorded.Conclusion PC-rRPLND is a reliable and technically reproducible procedure with safe oncological outcomes and acceptable postoperative ejaculatory function in well selected patients with NSGCTs.

刺参germ cell-less基因表达分析及转录因子预测

不同性别的刺参(Apostichopus japonicus)在生长速度、免疫能力等方面具有显著差异,解析其性别决定和性别分化机制具有重要的理论和经济价值。目前,刺参的性腺发育机制尚不清晰,挖掘性腺发育相关基因是解析其发育机制的重要途径。研究表明,germ cell-less基因在哺乳动物性腺发生中起重要作用,但无脊椎动物中关于germ cell-less基因的研究较少。本研究从刺参基因组中鉴定了germ cell-less (Ajgcl)基因片段,随后通过c DNA末端快速扩增技术(rapid amplification of c DNA ends,RACE)获得其全长c DNA序列。通过荧光定量PCR (real-time quantitative PCR,RT-q PCR)揭示了Ajgcl在成体组织中呈现泛表达状态,性腺中表达量最高,且雌性性腺中的表达量是雄性性腺中表达量的2.25倍。随着卵子的发生,Ajgcl的表达量呈现先上升后下降的动态表达变化,而在精子发生的过程中其表达量变化不大,意味着其可能在卵子发生过程中发挥重要作用。在整个胚胎发育过程中均能检测到Ajgcl转录本,意味着Ajgcl作为母源因子可能与原始生殖细胞的形成有关。此外,Ajgcl基因启动子中具有Oct-1、FOXD3、PAX-6、CRP、c-Myb和NF-1等转录因子的结合位点。本研究为深入解析germ cell-less基因在刺参等无脊椎动物性腺发育中发挥的功能奠定了基础。

Testicular mixed germ cell tumor:A case report

BACKGROUND Testicular mixed germ cell tumors(TMGCTs)are rare malignant tumors that are more common in men aged 20–40 years.TMGCTs comprise two or more types of germ cell tumors that primarily affect the testis.Their onset is undetectable;thus,early diagnosis is challenging.However,early recognition and diagnosis substantially improve patient prognosis.CASE SUMMARY We evaluated a rare case of TMGCT in a male patient presenting with recurrent fever and left supraclavicular lymphadenectasis instead of testicular enlargement and pain,which may easily lead to misdiagnosis.We report the clinical signs and symptoms,histopathological characteristics,and immunohistochemical results of this case of malignant TMGCT.CONCLUSION Our case,which was typical with multiple components,along with a literature review,may serve as a basis for early diagnosis.

Culture of Embryonic Stem Cell by Primordial Germ Cells of Down Producing Goat

[Objective] The paper was to establish embryonic stem cell system of goats. [Method] Numerous primordial germ cell colonies were derived from gonadal ridge and the surrounding tissues in 20 millimeter fetuses of down producing goat. Primordial germ cells and goats embryonic fibroblasts obtained from conceptus of equivaient gestational age were co-cultured. [Result] The colonies showed some characteristics of embryonic stem cells, such as the morphology of nest-like, they continued to be AKP positive and the ability to be continuously passed [Conclusion] These cells were pluripotent and ES-like cells.

Improved Isolation and Culture of Embryonic Germ Cells from Guanzhong Dairy Goat

A total of 219 embryonic-germ-cell-like （EG-like） clumps were derived from 15 selected goat fetuses. Isolation of primordial germ cells （PGCs） based on co-culture with primary goat embryonic fibroblast showed no difference from traditional feeder layer-based culture method used in mouse and human. The putative primary EG colonies were multilayer clumps of compact cells with unclear cell-cell boundaries. Three subculture methods of goat EG-like colony, traditional enzymatic digestion, mechanical cutting and combination of the both, were compared in this study. As a result, EG-like colonies traditionally disassociated with collagenase 1V could be subcultured for up to 4 passages. And the mechanically disaggregated EG-like colonies were successfully maintained 9-12 passages with or without enzymatic treatment. The pluripotency of the EG-like colonies was identified by their specific marker staining, spontaneous differentiation and embryoid bodies （EBs） formation in vitro. Most goat EG-like colonies （〉 80%） were AKP positive and immunocytochemically characterized with positive SSEA-1, Oct-4 and c-kit staining but SSEA-4. Under the condition of delaying passage, goat EG-like cells could differentiate into fibroblast-like, epithelium-like, and neuron-like cells. In addition, EBs could be obtained successfully in routine hanging drop culture. The serum free culture system （feeder layer-based） used in this study was suitable for keeping PGCs and EG-like cells in their undifferentiated condition, but failed to converse them to immortal cells. These results indicated that mechanical cutting is an effective method for passaging goat EG cell colonies. However, the microenvironment of conversing EG cells to immortal cells is still unclear.

Molecular and epigenetic pathogenesis of germ cell tumors

The development of germ cell tumors(GCTs)is a unique pathogenesis occurring at an early developmental stage during specification,migration or colonization of primordial germ cells(PGCs)in the genital ridge.Since driver mutations could not be identified so far,the involvement of the epigenetic machinery during the pathogenesis seems to play a crucial role.Currently,it is investigated whether epigenetic modifications occurring between the omnipotent two-cell stage and the pluripotent implanting PGCs might result in disturbances eventually leading to GCTs.Although progress in understanding epigenetic mechanisms during PGC development is ongoing,little is known about the complete picture of its involvement during GCT development and eventual classification into clinical subtypes.This review will shed light into the current knowledge of the complex epigenetic and molecular contribution during pathogenesis of GCTs by emphasizing on early developmental stages until arrival of late PGCs in the gonads.We questioned how misguided migrating and/or colonizing PGCs develop to either type Ⅰ or type Ⅱ GCTs.Additionally,we asked how pluripotency can be regulated during PGC development and which epigenetic changes contribute to GCT pathogenesis.We propose that SOX2 and SOX17 determine either embryonic stem cell-like(embryonal carcinoma)or PGC-like cell fate(seminoma).Finally,we suggest that factors secreted by the microenvironment,i.e.BMPs and BMP inhibiting molecules,dictate the fate decision of germ cell neoplasia in situ(into seminoma and embryonal carcinoma)and seminomas(into embryonal carcinoma or extraembryonic lineage),indicating an important role of the microenvironment on GCT plasticity.

Surgical treatment of metastatic germ cell cancer

Among young men between the ages of 15 and 40 years,germ cell cancer is the most common solid tumor[1].The worldwide incidence of germ cell cancer is 70000 cases.Compared to all solid tumors of men,germ cell cancer accounts for 1%of all male tumors.Nevertheless,the mortality of this rare tumor entity is about 13%since 9507 patients died worldwide of germ cell cancer.The improvement in survival of germ cell cancer patients is due to a multimodal treatment of germ cell cancer including cisplatin-based chemotherapy and surgery leading to higher cure-rates even in advanced stages[1],whereas the increasing incidence of germ cell cancers cannot be thoroughly explained.In this article we review the current indications for surgery in metastatic germ cell cancers,highlight the strength and weaknesses of techniques and indications and raise the question how to improve surgical treatment in metastatic germ cell cancer.

Germ cell apoptosis induced by Ureaplasma urealyticum infection

Aim: To study the effect of Ureaplasma urealyticum (UU) infection on germ cell apoptosis of male rats. Meth-ods: Male rats were infected artificially with UU serotype 8 (T_(960)). Morphological changes of germ cells in the sem-iniferous tubules and the lumen of the epididymides were observed under the light microscope. Fluorescence-conjugatedpolyclonal antibodies to Fas and Fas ligand (FasL) were used to localize Fas and FasL. TUNEL staining of germ cellsand Sertoli cells was performed by the AKPase method. TUNEL-positive rate (% positive cells) and TUNEL-positivearea (area occupied by stained cells) were analysed by KS400 Image Analysis System. The DNA laddering analysiswas performed by agarose gels electrophoresis. Results: In those rats infected with UU; (1) Exfoliated germ cellswere dramatically increased. Many multinucleated giant cells were found in the seminiferous tubules and the lumen ofthe epididymides. (2) The number of TUNEL-positive cells and the TUNEL-positive area were significantly increased.(3) The expression of Fas and FasL in germ cells and Sertoli cells was up-regulated. (4) Discrete bands of fragmentedDNA were found in the testicular cells. Conclusion: In male rats, germ cell apoptosis was increased in UU infec-tion . (Asian J Androl 2001 Sep; 3: 199 - 204)

Generation of male germ cells from induced pluripotent stem cells （iPS cells）： an in vitro and in vivo study

Recent studies have reported that induced pluripotent stem （iPS） cells from mice and humans can differentiate into primordial germ cells. However, whether iPS cells are capable of producing male germ cells is not known. The objective of this study was to investigate the differentiation potential of mouse iPS cells into spermatogonial stem cells and late-stage male germ cells. We used an approach that combines in vitrodifferentiation and in vivotransplantation. Embryoid bodies （EBs） were obtained from iPS cells using leukaemia inhibitor factor （LIF）-free medium. Quantitative PCR revealed a decrease in Oct4 expression and an increase in StraSand Vasa mRNA in the EBs derived from iPS cells, iPS cell-derived EBs were induced by retinoic acid to differentiate into spermatogonial stem cells （SSCs）, as evidenced by their expression of VASA, as well as CDH1 and GFRal, which are markers of SSCs. Furthermore, these germ cells derived from iPS cells were transplanted into recipient testes of mice that had been pre-treated with busulfan. Notably, iPS cell-derived SSCs were able to differentiate into male germ cells ranging from spermatogonia to round spermatids, as shown by VASA and SCP3 expression. This study demonstrates that iPS cells have the potential to differentiate into late-stage male germ cells. The derivation of male germ cells from iPS cells has potential applications in the treatment of male infertility and provides a model for uncovering the molecular mechanisms underlying male germ cell development.

Assessment of germ cell apoptosis in cryptorchid rats

Aim: To investigate the relationship between germ cell degeneration and apoptosis in cryptorchid rats. Methods: Thirteen 21-day-old Wistar rats were made unilaterally cryptorchid by closing the left inguinal canal. At day 30 (Group 1, n=6) and day 60 (Group 2, n=7) after operation, the testes were removed for histopathological examination. The controls (n=8) were sham operated and were sacrificed at day 60. Germ cell apoptosis was assessed by means of the TUNEL method. Results: Spermatogenesis was arrested and the testicular and seminiferous tubular diameters were significantly reduced In the unilateral undescended testes (UUTs) compared with the contralateral descended testes (CDTs) and the control rats. However, atrophic changes, pathological calcification, necrosis of seminiferous tubule, and absence or sloughing of germ cells were not found in all the animals. The spermatocytes were the main type of germ cells undergoing apoptosis in all the groups. In the UUTs, there was a significant and time-dependent increase in the mean apoptotic index. By 60 days after surgery, increased apoptosis in germ cells was also observed in the CDTs. Conclusion: Apoptosis is the predominant mechanism of germ cell death rather than atrophy and necrosis in cryptorchidism.

Expression of germ cell nuclear factor in mouse germ cells and sperm during postnatal period

Aim: To assess the spatial and temporal expression of germ cell nuclear factor (GCNF) in male mouse germ cells during postnatal development and in sperm before and after capacitation. Methods: The indirect immun-ofluorescence method with anti-GCNF antiserum was used to investigate the GCNF expression in mice at day 8, 10, 14, 17, 20, 28, 35, 70, and 420 after birth and in sperm before and after capacitation. Results: With the proceeding of spermatogenesis, GCNF was first detected in the nuclei of spermatogonia and a few early stage primary sperma-tocytes at day 8, which was increased gradually at day 10 to 14 inclusive. From day 17 to day 20, the GCNF was concentrated in round spermatids, while both spermatogonia and early stage primary spermatocytes became GCNF negative. From day 28 until day 420, strong GCNF expression was shown in round spermatids and pachytene spermatocytes, while spermatogonia, early primary spermatocytes and elongating spermatids were all GCNF negative. In addition, it was also found that GCNF was localized on the acrosomal cap region of spermatozoa and there was a big change in GCNF expression during capacitation, from 98 % GCNF positive before capacitation to about 20 % positive following capacitation. The localization of GCNF in caput and cauda spermatozoa was similar. Conclusion: GCNF may play important roles in spermatogenesis, capacitation and fertilization.

Optimal dose of busulfan for depleting testicular germ cells of recipient mice before spermatogonial transplantation

Successful spermatogonial transplantation requires depletion of the host germ cells to allow efficient colonization of the donor spermatogonial stem cells. Although a sterilizing drug,busulfan （Myleran）,is commonly used for preparing a recipient mouse before transplantation,the optimal dose of this drug has not yet been defined.The present study investigated the effects of different doses of busulfan （10-50 mg per kg body weight） on survival rate,testicular mass and histomorphology,and on the haploid spermatids and spermatozoa of male BALB/c mice.The results suggest that a dosage of 30 mg kg^-1 is optimal for the ablative treatment withbusulfan used to prepare the recipient mice. This dose results in an adequate depletion of the host germ cells for colonization of donorderived spermatogonial stem cells and causes the lowest death rate of the animals.

Effect of prolonged cryptorchidism on germ cell apoptosisand testicular sperm count

Aim: To evaluate the long term effect of experimental cryptorchidism on germ cell apoptotic rate and testicular sperm content in adult rats. Methods: Bilateral cryptorchidism was created in 40 adult male Sprague-Dawley rats by surgically manipulating the testes into the abdominal cavity and closing the internal inguinal ring. The rats were sacrificed and the testes removed 6 hours and 2, 4, 7, 21, 28 and 56 days after cryptorchidism. Germ cell apoptosis was quantified by means of TUNEL assay and apoptosis was confirmed using transmission electron microscopy. Results: The rate of apoptosis peaked at 4 days of cryptorchidism and then progressively declined to a nadir at 14 days of cryptorchidism. At 56 days of cryptorchidism, the germinal epithelium was largely depleted by the apoptotic process and only a few mature sperm were seen within the testis. At this point, a few tubules were seen to be repopulating with primary spermatocytes and the level of germ cell apoptosis began to increase marginally. Testicular sperm count (TSC) began to decline rapidly at day 7 of cryptorchidism. Only a few mature sperm were found in the testes of rats following 56 days of cryptorchidism. Multinucleated giant cells (MGC) were most numerous within the seminiferous tubules at day 4. At day 7, 35 % of MGCs were TUNEL positive. At all subsequent time points, however, MGCs fail to stain positive for apoptosis. This resumption of increased apoptosis coincided with the appearance of a population of primary spermatocytes in some seminiferous tubules. Moreover, there was not a corresponding increase in the number of mature sperm after 56 days of cryptorchidism. Conclusion: The decline in germ cell apoptosis after 4 days of cryptorchidism can be attributed to be the result of an overall depletion of germ cells. It appears that after a prolonged cryptorchidism (56 days), there is a limited resumption of spermatogenesis presumably as a result of a decrease in the maturing germ cells undergoing programmed cell death.

Spatial and temporal expression of germ cell nuclear factorin murine epididymis

Aim: To investigate the spatial and temporal expression of germ cell nuclear factor (GCNF) in mouse and rat epididymis during postnatal period. Methods: The epididymal sections from different postnatal days were stained for GCNF by the indirect immunofluorescence technique and digital photographs were taken by a Carl Zeiss confocal microscope. Results: GCNF was first detected on day 12 in mouse epididymis and day 14 in rat epididymis. The highest expression of GCNF was observed on day 35 in both mouse and rat epididymis. In adults, GCNF exhibited a region-specific expression pattern, i.e., it was expressed predominantly in the initial segment, caput and proximal corpus of rat epididymis and was abundant in the proximal corpus of mouse epididymis. GCNF could be found in the nuclei of the principal, apical, narrow, clear and halo cells. Conclusion: GCNF may play an important role in epididymal differentiation and development and in sperm maturation.

Application of seminal germ cell morphology and semen biochemistry in the diagnosis and management of azoospermic subjects

Aim: To evaluate whether the study of seminal germ cell morphology (SGCM) and semen biochemistry could befruitfully utilized for the diagnosis and management of azoospermic subjects. Methods: In the semen, mature andimmature germ cells are contributed by the testes, 70% of glycerylphosphoryl choline (GPC) by the epididymis, fruc-tose mostly or solely by the seminal vesicles and acid phosphate (ACP) by the prostate. In 16 normal volunteers, 12vasectomized subjects and 186 azoospennic subjects, these parameters have been studied and the data have been ana-lyzed. Results: Both mature and immature germ cells are absent in the semen of vasectomized subjects as well as inobstructive azoospennia; GPC level is also significantly decreased in both these groups. In cases with non-obstructiveazoospermia immature germ cells are present and seminal GPC, ACP and fructose levels are normal. The diagnosis ofobstructive and non-obstructive azoospermia based on these parameters correlated well with 'correct' testicular biopsyfindings. In some cases of azoospermia due to hypospermatogenesis or spermatogenic developmental arrest, the SGCMstudies were very helpful in objectively monitoring the response of the germinal tissue to specific treaunents. Conclu-sion: SGCM and semen biochemical parameters are very valuable non-invasive markers for differentiating obstructivefrom non-obstructive azoospermia. The SGCM findings serve as a dependable non-invasive testicular marker with highpredictive value. (Asian J Androl 2001 Mar; 3: 55-62)

FISH studies of chromosome abnormalities in germ cells and its relevance in reproductive counseling

Chromosome abnormalities are one of the major causes of human infertility. In infertile males, abnormal karyotypes are more frequent than in the general population. Furthermore, meiotic disorders affecting the germ cell-line have been observed in men with normal somatic karyotypes consulting for infertility. In both cases, the production of unbalanced spermatozoa has been demonstrated. Basically addressed to establish reproductive risks, fluorescence in situ hybridization （FISH） on decondensed sperm heads has become the most frequently used method to evaluate the chromosomal constitution of spermatozoa in carriers of numerical sex chromosome abnormalities, carriers of structural chromosome reorganizations and infertile males with normal karyotype. The aim of this review is to present updated figures of the information obtained through sperm FISH studies with an emphasis on its clinical significance. Furthermore, the incorporation of novel FISH-based techniques （Multiplex-FISH; Multi-FISH） in male infertility studies is also discussed. （Asian J Androl 2005 Sep; 7： 227-236）

Histological Observation of Germ Cell Development and Discovery of Spermatophores in Ovoviviparous Black Rockfish(Sebastes schlegeli Hilgendorf) in Reproductive Season

Black rockfish(Sebastes schlegeli) is an important species for culture; however, its reproductive characteristics have not been fully documented. In this study, we investigated the morphology and developmental process of germ cells in this ovoviviparous rockfish in reproductive season(October 2011–November 2012) with histological methods. We found that the gonad of mature fish showed notable seasonal changes in developmental characteristics and morphological structure. The sperm cells matured during a period lasting from October to December, significantly earlier than the oocytes did. A large number of spermatozoa and other cells occurred in testis at different developmental stages. Vitellogenesis in oocytes began in October, and gestation appeared in April next year. Spermatophores were discovered for the first time in Sebastes, which assembled in testis, main sperm duct, oviduct and genital tract, as well as ovarian cavity in October and April. These organs may serve either as production or hiding places for spermatophores and spermatozoa which were stored and transported in form of spermatophores. Testicular degeneration started from the distal part of testis in April, with spermatophores assembled in degenerating testis and waiting for transportation. The copulation probably lasted for a long period, during which the spermatozoa were discharged in batches as spermatophores. These spermatophores were coated with sticky materials secreted from the interstitial areas of testis and the main sperm duct, then transported into ovary.

Enhancement of mouse germ cell-associated genes expression by injection of human umbilical cord mesenchymal stem cells into the testis of chemical-induced azoospermic mice

Various methods are currently under investigation to preserve fertility in males treated with high-dose chemotherapy and radiation for malignant and nonmalignant disorders. Human umbilical cord mesenchymal stem cells （HUC-MSCs）, which possess potent immunosuppressive function and secrete various cytokines and growth factors, have the potential clinical applications. As a potential alternative, we investigate whether injection of HUC-MSCs into the interstitial compartment of the testes to promote spermatogenic regeneration efficiently. HUC-MSCs were isolated from different sources of umbilical cords and injected into the interstitial space of one testis from 10 busulfan-treated mice （saline and HEK293 cells injections were performed in a separate set of mice） and the other testis remained uninjected. Three weeks after MSCs injection, Relative quantitative reverse transcription polymerase chain reaction was used to identify the expression of 10 of germ cell associated, which are all related to meiosis, demonstrated higher levels of spermatogenic gene expression （2-8 fold） in HUC-MSCs injected testes compared to the contralateral uninjected testes （five mice）. Protein levels for germ cell-specific genes, miwi, vasa and synaptonemal complex protein （Scp3） were also higher in MSC-treated testes compared to injected controls 3 weeks after treatment. However, no different expression was detected in saline water and HEK293 cells injection control group. We have demonstrated HUC-MSCs could affect mouse germ cell-specific genes expression. The results also provide a possibility that the transplanted HUC-MSCs may promote the recovery of spermatogenesis. This study provides further evidence for preclinical therapeutic effects of HUC-MSCs, and explores a new approach to the treatment of azoospermia.

Targeting lentiviral vectors to primordial germ cells(PGCs):An efficient strategy for generating transgenic chickens

Recent advances in avian transgenic studies highlight the possibility of utilizing lentiviral vectors as tools to generate transgenic chickens. However, low rates of gonadal chimerism and germ line transmission efficiency still limit the broad usage of this method in creating transgenic chickens. In this study, we implemented a simple strategy using modified lentiviral vectors targeted to chicken primordial germ cells(PGCs) to generate transgenic chickens. The lentiviral vectors were pseudotyped with a modified Sindbis virus envelope protein(termed M168) and conjugated with an antibody specific to PGC membrane proteins. We demonstrated that these optimized M168-pseudotyped lentiviral vectors conjugated with SSEA4 antibodies successfully targeted transduction of PGCs in vitro and in vivo. Compared with the control, 50.0%–66.7% of chicken embryos expressed green fluorescent protein(GFP) in gonads transduced by the M168-pseudotyped lentivirus. This improved the targeted transduction efficiency by 30.0%–46.7%. Efficient chimerism of exogenous genes was also observed. This targeting technology could improve the efficiency of germ line transmission and provide greater opportunities for transgenic poultry studies.

Low hypoxia inducible factor-1α(HIF-1α)expression in testicular germ cell tumors--a major reason for enhanced chemosensitivity?

The molecular basis for enhanced chemosensitivity of testicular germ cell tumors （GCT） has been an area of great interest, as it could potentially give us therapeutic leads in other resistant malignancies. Thus far, however, the increased sensitivity of C＆T has been variously attributed to multiple factors -- an inability to detoxify cisplatin, a lack of export pumps, an inability to repair the DNA damage, an intact apoptotic cascade and lack of p53 mutation; but a unifying underlying etiology leading to the aforementioned processes and having a translational implication has so far been elusive. Herein, we offer evidence to support a potential significant role for the previously demonstrated low hypoxia inducible factor-la （HIF-la） expression in mediating the general exquisite chemosensitivity of testicular GCT, through the aforementioned processes. This molecular mechanism based hypothesis could have a significant translational implication in platinum refractory GCT as well as other platinum resistant malignancies.