ARTICLE | doi:10.20944/preprints202305.2044.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: relapsed germ cell tumors; salvage chemotherapy; conventional dose chemotherapy; high dose chemotherapy; autologous stem cell transplant
Online: 30 May 2023 (04:48:08 CEST)
Background: Although metastatic GCT is highly curable with initial cisplatin-based chemotherapy (CT), 20-30% of patients relapse. Salvage CT options include conventional (CDCT) and high dose chemotherapy (HDCT), however definitive comparative data remains lacking. We aimed to characterize the contemporary practice patterns of salvage CT across Canada. Methods: We conducted a 30-question online survey for Canadian medical and hematological oncologists with experience in treating GCT, assessing treatment availability, patient selection, and management strategies used for relapsed GCT patients. Results: Respondents included 30 staff; from 18 cancer centers across provinces. The most common CDCT regimens used were TIP (64%) and VIP (25%). HDCT was available for (70%) in 13 centers. HDCT regimen used included carboplatin and etoposide for 2 cycles (76% in 7 centers), 3 cycles (6% in two centers), and the TICE protocol (11%, in 2 centers). “Bridging” CDCT was used by 65% respondents. Post HDCT treatments considered include surgical resection for residual disease (87.5%), maintenance etoposide (6.3%) and sur-veillance only (6.3%). Conclusions: HDCT is the most commonly used GCT salvage strategy in Canada. Significant differences exist in the treatment availability, selection and delivery of HDCT, highlighting the need for standardization of care for patients with relapsed testicular GCT.
ARTICLE | doi:10.20944/preprints202211.0080.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Tumor initiation; Germ cell traits of tumors; Primordial germ cell-like tumor cells; Somatic to Pri-mordial germ cell-like transformation; Embryonic/germ cell hypothesis of tumor; Breast cancer
Online: 4 November 2022 (01:04:58 CET)
It has been proposed that tumourigenicity was an intrinsic feature of embryonic/germ cell developmental axis as well as embryonic/germ cell-related genes play a crucial role in tumourigenicity. Our previous studies indicated that primordial germ cell (PGC)-like potential could be reactivated in tumourigenesis. In this study, 4T1, 168FARN and 67NR cells which originated from the same mouse breast cancer were studied and the results indicated that the acquisition of embryonic/germ cell-like state is essential for tumourigenicity. We further demonstrated that somatic to PGC-like transformation (SPLT) was activated in 4T1 cells and that inhibition of PGC-like cell formation by depleting pluripotency and/or PGC specification-related genes markedly repressed SPLT and the tumourigenicity. Collectively, our findings reveal that tumourigenicity is linked to the acquisition of PGC-like state through SPLT in 4T1 cells, provide new insight into deeper understanding the biological nature of tumours and novel therapeutical strategies for cancer targeting.
ARTICLE | doi:10.20944/preprints202106.0662.v1
Subject: Medicine And Pharmacology, Immunology And Allergy Keywords: gonad; germ cell; genital duct; fetus; horse
Online: 28 June 2021 (14:14:06 CEST)
It was the aim of this study to provide a more precise timeframe of development of the gonads and genital ducts in the equine fetus around the time of sexual differentiation. This included the identification and localisation of the primordial germ cell population. Equine fetuses between 45 and 60 days of gestation were evaluated using a combination of micro-computed tomography scanning, immunohistochemistry, and multiplex immunofluorescence. Fetal gonads increased in size by 23-fold from 45 to 60 days of gestation, paralleled by a greater increase in metanephros volume. Signs of mesonephros atrophy were detected during this time. Tubular structures of the fetal testes were present from day 50 onwards, whereas cell clusters dominated in the fetal ovary. The genital ducts were well-differentiated and presented a lumen in all samples. No sign of mesonephric or paramesonephric duct degeneration was detected. Expression of AMH was strong in the fetal testes but absent in ovaries. Irrespective of sex, primordial germ cells selectively expressed LIN28. Migration of primordial germ cells from the mesonephros to the gonad was detected at 45 days, but not at 60 days of development. Their number and distribution within the gonad were influenced (p<0.05) by fetal sex. Most primordial germ cells (86.8 ± 3.2% in females and 84.6 ± 4.7% in males) were characterized as pluripotent according to co-localization with CD117. However, only a very small percentage of primordial germ cells was proliferating (7.5 ± 1.7% in females and 3.2 ± 1.2% in males) based on co-localization with Ki67. It can be concluded that gonadal sexual differentiation in the horse occurs asynchronously with regard to sex but already before 45 days of gestation.
ARTICLE | doi:10.20944/preprints202103.0273.v1
Subject: Biology And Life Sciences, Endocrinology And Metabolism Keywords: testicular germ cell tumors (TGCTs); human seminoma; p75 neurotrophin receptor (p75NTR); p75NTR -signaling.
Online: 9 March 2021 (14:52:34 CET)
Several studies have demonstrated that the p75NTR low-affinity receptor of Nerve Growth Factor (NGF), is produced in abnormally large amounts in several human cancer types. However, the role of p75NTR varies substantially depending on cell context, so that a dual role of this receptor protein in tumor cell survival and invasion, as well as cell death, has been supported in recent studies. Herein we explored for the first time the expression of p75NTR in human specimens (nr=40) from testicular germ cell tumors (TGCTs), mostly seminomas. Nuclear overexpression of p75NTR was detected by immunohistochemistry in tumor tissue as compared to normal tissue, whereas neither NGF nor its high-affinity TrkA receptor was detected. An increased nuclear staining of phospho-JNK, belonging to the p75NTR signaling pathway, and its pro-apoptotic target gene, p53, was concomitantly observed. Interestingly, our analysis revealed that decreased expression frequency of p75NTR, p-JNK, and p53 was related to staging progression, thus suggesting that p75NTR may represent a specific marker of differentiation in TGCTs.
REVIEW | doi:10.20944/preprints202010.0037.v1
Subject: Biology And Life Sciences, Biochemistry And Molecular Biology Keywords: cadherin; cell adhesion; fertilization; folliculogenesis; gamete; germ cells; gonads; ovary; primordial germ cells; spermatogenesis; testis
Online: 2 October 2020 (10:31:31 CEST)
Cadherins are a group of membrane proteins responsible for cell adhesion. They are crucial for cell sorting and recognition during the morphogenesis, but also play many other roles such as assuring tissue integrity and resistance to stretching, mechanotransduction, cell signaling, regulation of cell proliferation, apoptosis, survival, carcinogenesis, etc. Within the cadherin superfamily, the E- and N-cadherin have been especially well studied. They are involved in many aspects of sexual development and reproduction, such as germline development and gametogenesis, gonad development and functioning, and fertilization. E-cadherin is expressed in the primordial germ cells, (PGCs) and also participates in PGC migration to the developing gonads where they become enclosed by the N-cadherin-expressing somatic cells. The differential expression of cadherins is also responsible for the establishment of the testis or ovary structure. In the adult testes, the N-cadherin is responsible for the integrity of the seminiferous epithelium, regulation of sperm production, and the establishment of the blood-testis barrier. Sex hormones regulate the expression and turnover of N-cadherin influencing the course of spermatogenesis. In the adult ovaries, E- and N-cadherin assure the integrity of ovarian follicles and the formation of corpora lutea. Cadherins are expressed in the mature gametes, and facilitate the capacitation of sperm in the female reproductive tract, and gamete contact during fertilization. The germ cells and accompanying somatic cells express a series of different cadherins, however, their role in gonads and reproduction is still unknown. In this review, we show what is known and unknown about the role of cadherins in the germline and gonad development, and suggest the topics for future research.
REVIEW | doi:10.20944/preprints202301.0519.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: ovarian cancer; machine learning; germ line; genetic risk scores
Online: 28 January 2023 (06:58:55 CET)
Ovarian cancers are curable by surgical resection when discovered early enough. Unfortunately, most ovarian cancers are diagnosed in the later stages. One strategy to identify early ovarian tumors is to screen women who have the highest risk scores. This mini review summarizes the accuracy of different methods used to assess the risk of developing ovarian cancer, including family history, BRCA genetic tests, and polygenic risk scores. The accuracy of these is compared to the maximum theoretical accuracy, revealing a substantial gap. We suggest that this gap, or missing heritability, could be caused by epistatic interactions between genes. An alternative approach to computing genetic risk scores, using chromosomal-scale length variation should incorporate epistatic interactions. Future research in this area should focus on this and other alternative methods of characterizing genomes.
BRIEF REPORT | doi:10.20944/preprints202109.0492.v1
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: Adenocarcinoma of lung; Ductal carcinoma; Breast Neoplasms; ErbB receptors; Germ cells
Online: 29 September 2021 (11:41:12 CEST)
The epidermal growth factor receptor (EGFR) exon-19 deletion is one of the most common mutations detected in lung cancer patients. Although exon-19 deletion is frequently detected in adenocarcinoma, observing this mutation in germline cells is very rare. Besides, the co-occurrence of homozygous and heterozygous mutations in dual primary cancers in a person is very uncommon. This article presents a 53-year-old Iranian woman with no history of smoking who was diagnose with two primary cancers; invasive ductal carcinoma, and primary pulmonary lung adenocarcinoma. The case reported a history of breast cancer in her sister and a history of lung cancer in her father. To select the best choice of treatment the EGFR gene was analyzed with Sanger’s sequencing method from DNA extracted from the patient’s lung tissue sample. Observing two primary cancers in this patient and considering her family pedigree, germline cells were also analyzed using samples recruited from the patient’s peripheral blood to investigate any EGFR mutations in her germline cells. The obtained data revealed that the lung tissue of the patient carried a homozygous form of EGFR exon-19 deletion while her peripheral blood contained a heterozygous form of this mutation, which is exceptionally rare.
ARTICLE | doi:10.20944/preprints202103.0517.v1
Subject: Biology And Life Sciences, Anatomy And Physiology Keywords: pluripotency; naïve; stem; imprinting; primordial germ cells; trophoblast; CDK8; Mediator; enhancers
Online: 22 March 2021 (11:19:21 CET)
Keywords: pluripotency; naïve; stem; imprinting; primordial germ cells; trophoblast; CDK8; Mediator; enhancers.
CASE REPORT | doi:10.20944/preprints202309.0305.v3
Subject: Medicine And Pharmacology, Oncology And Oncogenics Keywords: mature triphyllic cystic teratoma; posterior mediastinum; fetal teratoma; germ cell tumor; prenatal diagnosis
Online: 18 September 2023 (07:14:56 CEST)
A teratoma is a neoplasm composed of cell populations or tissues that remind, in their appearance, normal elements derived from at least two embryonic layers. Fetal mature teratomas are normally benign, cystic, and typically occur along the midline, while they are rare in the posterior mediastinum. Teratomas are frequently solitary, however they may sometimes be associated with other congenital anomalies and/or with chromosomal abnormalities. Clinically, they are often asymptomatic but can occasionally cause compression symptoms. Prenatal diagnoses are uncommon and made with ultrasonography; differential diagnosis with other congenital conditions is mandatory. We report the case of a 21 weeks of gestational age-old fetus with a Mature Triphyllic Fetal Cystic Teratoma, grade 0, located in the right posterior mediastinum.
REVIEW | doi:10.20944/preprints202101.0625.v1
Subject: Medicine And Pharmacology, Neuroscience And Neurology Keywords: Alzheimer’s disease; dementia, beta-amyloid; germ theory; drug development; clinical trials; herpes; spirochetes; Chlamydia pneumoniae; Porphyromonas gingivalis; toxoplasma; mycobacteria
Online: 29 January 2021 (13:57:18 CET)
There is now considerable evidence that several infectious agents (viruses, bacteria, or parasites) may play a contributing role in the development of Alzheimer’s disease (AD). The six primary suspects are herpes viruses, spirochetal bacteria, Chlamydia pneumoniae, Porphyromonas gingivalis, mycobacteria, and toxoplasma parasites. Also, some of the antimicrobial and antiviral agents that are used to treat them have shown promise for AD interventions. I describe this evidence and assert it is now time to accelerate clinical trials of these existing drugs, already federally approved, to determine if such treatments can delay, halt, or reverse AD.