SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Testicular cancer

152

Pancreatic cancer is known to be one of the most lethal cancers. The majority of patients present with advanced stage disease, making curative approach unachievable. In untreated patients, the median survival does not exceed 6 months in metastatic disease and 10 months in locally advanced disease. Furthermore, the 5-year survival rate remains poor even in patients with early stage disease who are surgical candidates. The detrimental outcome is related to the high potency of developing metastasis which can be detected at diagnosis, when the disease progresses or relapses after surgery. Although the liver is the most common site of pancreatic cancer metastases, the cancer can escape the liver in some cases and metastasize to the lung or other distant organs. The involvement of some sites not others might reflect subgroups of this cancer with different molecular backgrounds. Identifying these groups may have utility in determining prognosis and stratifying treatment for patients.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Lymph node, Prostate cancer, Testicular cancer

144

While the nonpalpable testis represents only a small portion of all cryptorchid testes, it remains a clinical challenge for pediatric urologists. Many controversies about the best evaluation and management exist. This narrative review serves as an update on what is known about the nonpalpable testis: etiology, pre-operative evaluation, the best surgical management, novel techniques, and ongoing controversies.

Concepts: Medicine, Andrology, Testicle, Testicular cancer, Novel, Orchiopexy, Cryptorchidism

99

Stochastic and proliferative events initiated from a single cell can disrupt homeostatic balance and lead to fatal disease processes such as cancer metastasis. To overcome metastasis, it is necessary to detect and quantify sparsely distributed metastatic cells throughout the body at early stages. Here, we demonstrate that clear, unobstructed brain/body imaging cocktails and computational analysis (CUBIC)-based cancer (CUBIC-cancer) analysis with a refractive index (RI)-optimized protocol enables comprehensive cancer cell profiling of the whole body and organs. We applied CUBIC-cancer analysis to 13 mouse models using nine cancer cell lines and spatiotemporal quantification of metastatic cancer progression at single-cell resolution. CUBIC-cancer analysis suggests that the epithelial-mesenchymal transition promotes not only extravasation but also cell survival at metastatic sites. CUBIC-cancer analysis is also applicable to pharmacotherapeutic profiling of anti-tumor drugs. CUBIC-cancer analysis is compatible with in vivo bioluminescence imaging and 2D histology. We suggest that a scalable analytical pipeline with these three modalities may contribute to addressing currently incurable metastatic diseases.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Chemotherapy, Prostate cancer, Testicular cancer

88

Walking is an adaptable, inexpensive and accessible form of physical activity. However, its impact on quality of life (QoL) and symptom severity in people with advanced cancer is unknown. This study aimed to assess the feasibility and acceptability of a randomised controlled trial (RCT) of a community-based walking intervention to enhance QoL in people with recurrent/metastatic cancer.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Randomized controlled trial, Prostate cancer, Testicular cancer

59

Clear-cell renal cell carcinoma (ccRCC) exhibits a broad range of metastatic phenotypes that have not been systematically studied to date. Here, we analyzed 575 primary and 335 metastatic biopsies across 100 patients with metastatic ccRCC, including two cases sampledat post-mortem. Metastatic competence was afforded by chromosome complexity, and we identify 9p loss as a highly selected event driving metastasis and ccRCC-related mortality (p = 0.0014). Distinct patterns of metastatic dissemination were observed, including rapid progression to multiple tissue sites seeded by primary tumors of monoclonal structure. By contrast, we observed attenuated progression in cases characterized by high primary tumor heterogeneity, with metastatic competence acquired gradually and initial progression to solitary metastasis. Finally, we observed early divergence of primitive ancestral clones and protracted latency of up to two decades as a feature of pancreatic metastases.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Extracellular matrix, Prostate cancer, Testicular cancer

48

Despite decades of effort, little progress has been made to improve the treatment of cancer metastases. To leverage the central role of the mechanoenvironment in cancer metastasis, we present a mechanoresponsive cell system (MRCS) to selectively identify and treat cancer metastases by targeting the specific biophysical cues in the tumor niche in vivo. Our MRCS uses mechanosensitive promoter-driven mesenchymal stem cell (MSC)-based vectors, which selectively home to and target cancer metastases in response to specific mechanical cues to deliver therapeutics to effectively kill cancer cells, as demonstrated in a metastatic breast cancer mouse model. Our data suggest a strong correlation between collagen cross-linking and increased tissue stiffness at the metastatic sites, where our MRCS is specifically activated by the specific cancer-associated mechano-cues. MRCS has markedly reduced deleterious effects compared to MSCs constitutively expressing therapeutics. MRCS indicates that biophysical cues, specifically matrix stiffness, are appealing targets for cancer treatment due to their long persistence in the body (measured in years), making them refractory to the development of resistance to treatment. Our MRCS can serve as a platform for future diagnostics and therapies targeting aberrant tissue stiffness in conditions such as cancer and fibrotic diseases, and it should help to elucidate mechanobiology and reveal what cells “feel” in the microenvironment in vivo.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Chemotherapy, Prostate cancer, Testicular cancer

42

Testicular germ cell tumors (TGCTs) are among the most responsive solid cancers to conventional chemotherapy. To elucidate the underlying mechanisms, we developed a mouse TGCT model featuring germ cell-specific Kras activation and Pten inactivation. The resulting mice developed malignant, metastatic TGCTs composed of teratoma and embryonal carcinoma, the latter of which exhibited stem cell characteristics, including expression of the pluripotency factor OCT4. Consistent with epidemiological data linking human testicular cancer risk to in utero exposures, embryonic germ cells were susceptible to malignant transformation, whereas adult germ cells underwent apoptosis in response to the same oncogenic events. Treatment of tumor-bearing mice with genotoxic chemotherapy not only prolonged survival and reduced tumor size but also selectively eliminated the OCT4-positive cancer stem cells. We conclude that the chemosensitivity of TGCTs derives from the sensitivity of their cancer stem cells to DNA-damaging chemotherapy.

Concepts: Gene, Cancer, Oncology, Stem cell, Cellular differentiation, Testicular cancer, Germ cell tumor, Germ cell

40

Type II testicular germ cell cancers (TGCT) are the most frequently diagnosed tumours in young men (20-40 years) and are classified as seminoma or non-seminoma. TGCTs are commonly treated by orchiectomy and chemo- or radiotherapy. However, a subset of metastatic non-seminomas (embryonal carcinomas) displays only incomplete remission or relapse and requires novel treatment options. Recent studies have shown effective application of the small-molecule inhibitor JQ1 in tumour therapy, which interferes with the function of ‘bromodomain and extraterminal (BET)’ proteins. JQ1-treated TGCT cell lines display up-regulation of genes indicative for DNA damage and cellular stress response and induce cell cycle arrest. Embryonal carcinoma (EC) cell lines, which presented as JQ1 sensitive, display down-regulation of pluripotency factors and induction of mesodermal differentiation. In contrast, seminoma-like TCam-2 cells tolerated higher JQ1 concentrations and were resistant to differentiation. ECs xenografted in vivo showed a reduction in tumour size, proliferation rate and angiogenesis in response to JQ1. Finally, the combination of JQ1 and the histone deacetylase inhibitor romidepsin allowed for lower doses and less frequent application, compared with monotherapy. Thus, we propose that JQ1 in combination with romidepsin may serve as a novel therapeutic option for (mixed) TGCTs.

Concepts: DNA, Protein, Gene, Cell, Cancer, Oncology, Testicular cancer, Germ cell tumor

38

Patterns of genomic evolution between primary and metastatic breast cancer have not been studied in large numbers, despite patients with metastatic breast cancer having dismal survival. We sequenced whole genomes or a panel of 365 genes on 299 samples from 170 patients with locally relapsed or metastatic breast cancer. Several lines of analysis indicate that clones seeding metastasis or relapse disseminate late from primary tumors, but continue to acquire mutations, mostly accessing the same mutational processes active in the primary tumor. Most distant metastases acquired driver mutations not seen in the primary tumor, drawing from a wider repertoire of cancer genes than early drivers. These include a number of clinically actionable alterations and mutations inactivating SWI-SNF and JAK2-STAT3 pathways.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Chemotherapy, Prostate cancer, Testicular cancer

33

Cancer-associated fibroblasts (CAFs) are a major cancer-promoting component in the tumor microenvironment (TME). The dynamic role of human CAFs in cancer progression has been ill-defined because human CAFs lack a unique marker needed for a cell-specific, promoter-driven knockout model. Here, we developed an engineered human CAF cell line with an inducible suicide gene to enable selective in vivo elimination of human CAFs at different stages of xenograft tumor development, effectively circumventing the challenge of targeting a cell-specific marker. Suicide-engineered CAFs were highly sensitive to apoptosis induction in vitro and in vivo by the addition of a simple small molecule inducer. Selection of timepoints for targeted CAF apoptosis in vivo during the progression of a human breast cancer xenograft model was guided by a bi-phasic host cytokine response that peaked at early timepoints after tumor implantation. Remarkably, we observed that the selective apoptosis of CAFs at these early timepoints did not affect primary tumor growth, but instead increased the presence of tumor-associated macrophages and the metastatic spread of breast cancer cells to the lung and bone. The study revealed a dynamic relationship between CAFs and cancer metastasis that has counter-intuitive ramifications for CAF-targeted therapy.

Concepts: Cancer, Breast cancer, Metastasis, Oncology, Lung cancer, Chemotherapy, Prostate cancer, Testicular cancer