A Synergistic Interaction between Chk1- and MK2 Inhibitors in KRAS-Mutant Cancer.

KRAS is one of the most frequently mutated oncogenes in human cancer. Despite substantial efforts, no clinically applicable strategy has yet been developed to effectively treat KRAS-mutant tumors. Here, we perform a cell-line-based screen and identify strong synergistic interactions between cell-cycle checkpoint-abrogating Chk1- and MK2 inhibitors, specifically in KRAS- and BRAF-driven cells. Mechanistically, we show that KRAS-mutant cancer displays intrinsic genotoxic stress, leading to tonic Chk1- and MK2 activity. We demonstrate that simultaneous Chk1- and MK2 inhibition leads to mitotic catastrophe in KRAS-mutant cells. This actionable synergistic interaction is validated using xenograft models, as well as distinct Kras- or Braf-driven autochthonous murine cancer models. Lastly, we show that combined checkpoint inhibition induces apoptotic cell death in KRAS- or BRAF-mutant tumor cells directly isolated from patients. These results strongly recommend simultaneous Chk1- and MK2 inhibition as a therapeutic strategy for the treatment of KRAS- or BRAF-driven cancers.

Codon-specific translation reprogramming promotes resistance to targeted therapy.

Reprogramming of mRNA translation has a key role in cancer development and drug resistance 1 . However, the molecular mechanisms that are involved in this process remain poorly understood. Wobble tRNA modifications are required for specific codon decoding during translation2,3. Here we show, in humans, that the enzymes that catalyse modifications of wobble uridine 34 (U34) tRNA (U34 enzymes) are key players of the protein synthesis rewiring that is induced by the transformation driven by the BRAF V600E oncogene and by resistance to targeted therapy in melanoma. We show that BRAF V600E -expressing melanoma cells are dependent on U34 enzymes for survival, and that concurrent inhibition of MAPK signalling and ELP3 or CTU1 and/or CTU2 synergizes to kill melanoma cells. Activation of the PI3K signalling pathway, one of the most common mechanisms of acquired resistance to MAPK therapeutic agents, markedly increases the expression of U34 enzymes. Mechanistically, U34 enzymes promote glycolysis in melanoma cells through the direct, codon-dependent, regulation of the translation of HIF1A mRNA and the maintenance of high levels of HIF1α protein. Therefore, the acquired resistance to anti-BRAF therapy is associated with high levels of U34 enzymes and HIF1α. Together, these results demonstrate that U34 enzymes promote the survival and resistance to therapy of melanoma cells by regulating specific mRNA translation.

Inhibition of Cyclin-Dependent Kinase 8/Cyclin-Dependent Kinase 19 Suppresses Its Pro-Oncogenic Effects in Prostate Cancer.

Progression of prostate cancer (PCa) is characterized by metastasis and castration resistance after response to androgen deprivation. Therapeutic options are limited, causing high morbidity and lethality. Recent work reported pro-oncogenic implications of the Mediator subunits cyclin-dependent kinase (CDK) 8 and 19 for the progression of PCa. The current study explored the underlying molecular mechanisms of CDK8/CDK19 and tested effects of novel CDK8/CDK19 inhibitors. PC3, DU145, LNCaP, and androgen-independent LNCaP Abl were used for in vitro experiments. Two inhibitors and CDK19 overexpression were used to modify CDK8/CDK19 activity. MTT assay, propidium iodide staining, wound healing assay, Boyden chamber assay, and adhesion assay were used to investigate cell viability, cell cycle, migration, and adhesion, respectively. Peptide-kinase screen using the PamGene platform was conducted to identify phosphorylated targets. Combining CDK8/CDK19 inhibitors with anti-androgens led to synergistic antiproliferative effects and sensitized androgen-independent cells to bicalutamide. CDK8/CDK19 inhibition resulted in reduced migration and increased collagen I-dependent adhesion. Phosphorylation of multiple peptides linked to cancer progression was identified to be dependent on CDK8/CDK19. In summary, this study substantially supports recent findings on CDK8/CDK19 in PCa progression. These findings contribute to a better understanding of underlying pro-oncogenic effects, which is needed to develop CDK8/CDK19 as a therapeutic target in PCa.

Prospective study of computer-aided detection of colorectal adenomas in hospitalized patients.

BACKGROUND: Adenoma detection with polypectomy during total colonoscopy reduces the incidence of colorectal cancer (CRC) and colorectal cancer-associated mortality. The adenoma detection rate (ADR) is an established quality indicator, which is associated with a decreased risk for interval cancer. An increase in ADR could be demonstrated for several artificially intelligent, real-time computer-aided detection (CADe) systems in selected patients. Most studies concentrated on outpatient colonoscopies. This sector often lacks funds for applying costly innovations like CADe. Hospitals are more likely to implement CADe and information about the impact of CADe in the distinct patient cohort of hospitalized patients is scarce. METHODS: In this prospective, randomized-controlled study, we compared colonoscopies performed with or without computer-aided detection (CADe) system (GI Genius, Medtronic) performed at University Medical Center Schleswig-Holstein, Campus Luebeck. The primary endpoint was ADR. RESULTS: Overall, 232 patients were randomized with n = 122 patients in the CADe arm and n = 110 patients in the control arm. Median age was 66 years (interquartile range 51-77). Indication for colonoscopy was most often workup for gastrointestinal symptoms (88.4%) followed by screening, post-polypectomy and post-CRC surveillance (each 3.9%). Withdrawal time was significantly prolonged (11 vs. 10 min, p = 0.039), without clinical relevance. Complication rate was not different between the arms (0.8% vs. 4.5%; p = 0.072). The ADR was significantly increased in the CADe arm compared to the control (33.6% vs. 18.1%, p = 0.008). ADR increase was particularly strong for the detection in elderly patients aged ≥50 years (OR 6.3, 95% CI 1.7 - 23.1, p = 0.006). CONCLUSION: The use of CADe is safe and increases ADR in hospitalized patients.

Impact of stratified resection margin classification on local tumor control and survival in patients with oral squamous cell carcinoma.

BACKGROUND: Guidelines recommended for resection of oral cancer define a free margin of ≥5 mm as clear and safe (R0). This statement was questioned recently based on the assumption that different surgical margins may hold different risk categories. The aim of this study was to investigate the impact of stratification of the surgical margins on the survival outcome of patients with oral cancer. METHODS: In a cohort of 753 patients, the hazard ratio for local recurrence-free survival (LRFS), overall survival (OS), and oral cancer-specific survival (OCSS) were estimated for R0 resection, the close margin of 1-4 mm, involved resection borders but with free frozen sections. Competing risk factors were considered in the statistical regression model. RESULTS: One hundred seventy-three (23%) patients developed local recurrence and 316 (42%) died in the 5 follow-up years. There was a gradual improvement in the LRFS, OCSS, OS with the increase of clear margin. OS showed a similar tendency. CONCLUSION: Not all patients with an R0cm status carry the same risk for impaired LRFS, OCSS, and OS. Their risk to develop recurrence is higher than those patients with R0 ≥5 mm but stratified risk management can be recommended according to the presented results.

[IgG4-associated lung disease with granulomatous lesions : Coexistence of two entities or the spectrum of one disease?] / IgG4-assoziierte Lungenerkrankung mit granulomatösen Läsionen : Koexistenz zweier Entitäten oder das Spektrum einer Erkrankung?

A 54-year-old patient with a history of pulmonary tuberculosis and occupational exposure to dust in early adulthood presented with symptoms of coughing with sputum, weight loss, occasional night sweats, and thoracic pain. Non-necrotizing granulomatosis in lung and lymph-node biopsies indicated sarcoidosis. Combined immunosuppressive therapy did not lead to an improvement. An atypical lung resectate with fibroinflammatory changes and obliterative endothelialitis may finally lead to the diagnosis of IgG4-associated lung disease with a bronchovascular pattern of involvement. The question discussed here is whether this is a coexistence of IgG4-associated lung disease with sarcoidosis or the spectrum of one disease.

Myoid gonadal stromal tumor of the testis-the novel subtype of testicular gonadal stromal tumors: a case report and review of the literature.

BACKGROUND: Sex cord gonadal stromal tumors compose less than 10% of all testicular neoplasms and consist of a variety of histological subtypes. In 2016, the World Health Organization introduced a novel subtype, the myoid gonadal stromal tumor, that consists of spindle-shaped cells with immunohistologic features of muscle cells. Only few cases have been reported to date. Due to its rarity and owing to its only recent introduction, the current knowledge about myoid gonadal stromal tumor is limited, and particularly, appropriate clinical management is still ill-defined. CASE PRESENTATION: A 47-year-old man of Caucasian descent presented with nonspecific scrotal discomfort. A roundish and well demarcated hypoechoic mass of 8.5 mm in diameter was detected in the cranial region of the left testis. Serum tumor marker levels were within normal ranges. Testis-sparing surgery revealed a 9-mm whitish, hard mass with sharp surgical margin. Histologically, the neoplasm consisted of microfibrillar tissue with spindle-shaped cells harboring elongated nuclei. Immunohistochemical work-up disclosed expression of desmin, small muscle actin, and S100 protein giving evidence for the myogenic nature of the neoplastic cells. There was no indication of malignancy, neither histologically nor clinically. Follow-up of 1 year was uneventful. CONCLUSION: A literature survey revealed 22 previous cases of myoid gonadal stromal tumor. The median age was 37 years, the median size of the neoplasm was 20 mm, and there was no side-preponderance. Myoid gonadal stromal tumor is not much different from other subtypes of gonadal stromal tumors nor from testicular gem cell tumors regarding age and laterality; however, tumor size is smaller in myoid gonadal stromal tumors than in germ cell tumors. Although rarely performed so far, testis-sparing surgery probably constitutes an appropriate treatment of this neoplasm. Myoid gonadal stromal tumor represents an emerging novel entity of benign testicular new growths that caregivers of patients with testicular tumors should be aware of.

The impact of tumor budding and single-cell invasion on survival in patients with stage III/IV locally advanced oral squamous cell carcinoma- results from a prospective cohort study.

Introduction: Tumor budding (TB) refers to the presence of small clusters of tumor cells at the invasive front of a malignant tumor. Single tumor cell invasion (SCI) is an extreme variant of TB, in which individual loose tumor cells are present at the invasive front. Both TB and SCI are important histomorphologic risk factors postulated to indicate loss of cellular cohesion. In this study, we investigated the influence of TB and SCI on different survival outcomes in patients with locally advanced oral squamous cell carcinoma (OSCC). Methods: We included 129 patients with locally advanced OSCC (pT3-4) from a single-center, prospectively maintained cohort. We examined the association of TB and SCI with the presence of occult lymph node metastasis using a logistic regression model. Survival probabilities were estimated using the Kaplan-Meier method and cumulative incidence functions. The association of TB and SCI on overall survival (OS), oral cancer-specific survival (OCSS), and local recurrence-free survival (LRFS) was investigated using Cox's proportional hazards regression models. Results: TB was detected in 98 (76%) of the tumors, while SCI was observed in 66 (51%) patients. There was a significant association between TB and the occurrence of occult lymph node metastasis (OR=3.33, CI: 1.21-10.0). On multivariate analysis, TB had no detectable impact on survival outcomes. However, SCI showed a higher risk for local recurrence (Hazards ratio (HR): 3.33, CI: 1.19 - 9.27). Discussion: This study demonstrates that TB and SCI in locally advanced OSCC function as an independent risk factor for occult lymph node metastases, as well as local recurrences. Both histomorphologic risk factors could serve as an additional parameter for stratifying therapy and escalating multimodal treatment approaches.

The expression of the adenosine pathway markers CD39 and CD73 in salivary gland carcinomas harbors the potential for novel immune checkpoint inhibition.

BACKGROUND: In salivary gland carcinomas (SGC), there is only a small fraction of entities that appears to profit from immune checkpoint inhibition (ICI). Recent findings connected the activation of adenosine-signaling with a tolerogenic microenvironment. Therefore, the inhibition of adenosine pathway markers (CD39 and/or CD73) can augment ICI and/or display a novel immunotherapeutic strategy beyond ICI. Here, we assessed the immuno-histochemical expression of CD39 and CD73 across a wide spectrum of SGCs. METHODS: In total, 114 patients with SGCs consecutively diagnosed between 2001 and 2021 were assessed for clinicopathological baseline characteristics and underwent confirmatory histopathological review. Immunohistochemical expression levels of CD39 and CD73 were assessed by applying the tumor proportion score (TPS) and the immune proportional score (IPS) comparable to PD-L1 expression analysis in routine clinical practice. Additionally, findings were correlated with PD-L1 expression levels. RESULTS: The median age was 60.6 and 51.8% patients were female. The cohort covered a spectrum of eight distinct entities. Advanced-stage disease (UICC/AJCC III/IVA-IVC) at initial diagnosis was present in the majority of patients (64/114). Immunohistochemical staining revealed positivity for CD39 and CD73 in 48.2% and 21.1% on tumor cells (TPS ≥ 1%) as well as 46.4% and 42.9% within the immune cell infiltrate (IPS ≥ 1%), respectively. Further comparative analyses revealed immune-cold entities such adenoid cystic carcinoma (AdCC), immune-hot tumors such as adenocarcinoma, not otherwise specified (AC (NOS)) and entities with intermediate immunologic features such as acinic cell carcinoma (ACC). CONCLUSION: Current results indicate entity-specific adenosine signaling signatures. These findings suggest that the adenosine pathway plays a decisive role in tumor immunity among the major spectrum of SGCs. Targeting the adenosine pathway might pose a promising therapeutic option for selected entities.

Sarcomas of fat and bone: a case report.

Osteosarcomas are the most common primary malignant bone tumors and are classified by the WHO into several intramedullary and surface subtypes. One of these is the rare parosteal osteosarcoma. Liposarcomas are the second most common soft tissue sarcoma and are classified into several types ranging from intermediate to high grade tumors. In one of our recent patients we found an unusual combination of a parosteal osteosarcoma and a large fatty component, which fluorescence-in-situ-hybridization revealed as liposarcoma. Radiologists, pathologists, and surgeons should consider the possibility of bone and soft tissue malignancies consisting of different components, as this may be of paramount importance for oncologically complete resection.

The Benefit of Postoperative Radiotherapy and Extending Neck Dissection in pT1-2 Oral Squamous Cell Carcinoma With a Single Ipsilateral Cervical Lymph Node Metastasis (pN1).

BACKGROUND/AIM: We compared postoperative radiotherapy (PORT) to surgery only (SO), and supraomohyoidal neck dissection (SOHND) to modified radical neck dissection (MRND) in patients with pT1-T2 squamous cell carcinomas of the oral cavity (OSCC) and a single cervical lymph node metastasis (pN1) in terms of overall survival (OS), oral cancer specific survival (OCSS), and regional recurrence-free survival (RRFS), in a prospective cohort study. PATIENTS AND METHODS: We included patients with pT1-T2 pN1 OSCC with no distant metastasis and estimated the survival probabilities using the Kaplan-Meier method and calculated hazards ratios (HR) for PORT vs. SO and MRND vs. SOHND using adjusted Cox regression models. RESULTS: A total of 51 patients (26 SO vs. 25 PORT, 9 SOHND vs. 42 MRND) were evaluated. Patients who received PORT were more likely to be younger and healthier. OS at 5 years was 41% and 87% in the SO and PORT groups, respectively. OS at 5 years was 52% and 67% in the in the SOHND and MRND groups, respectively. Both OCSS and RRFS were improved by PORT. Extending neck dissection was not associated with improved OS (HR = 0.83). CONCLUSION: PORT is associated with preferable OS, OCSS, and RRFS in pT1-2 pN1 oral cancer and should be recommended regularly.

The sub-fascial pattern of the myocutaneous platysma flap - The anatomical basis and preliminary cases for oral reconstruction.

To verify the feasibility of the SF-MPF for oral reconstruction, the anatomic, sonographic and histologic features of the SF-MPF were investigated and the outcome in a series of patients was evaluated. The sonographic and histologic results showed a supra-fascial arterio-venous vascular blood supply to the sub-fascial design of the MPF. The clinical course of 12 consecutive patients who underwent oral reconstruction using the SF-MPF along with ipsi- or lateral neck dissection for treatment of oral cancer showed sufficient pedicle length and reliable blood supply. The SF-MPF is a reliable and safe pedicled myocutaneous flap. Therefore, it should be considered being an additional option when a pedicled flap has to be selected.

On the quest for hidden ovarian teratomas in therapy-refractory anti-NMDA receptor encephalitis: a case report.

BACKGROUND: Anti-NMDA-receptor (anti-NMDAR) encephalitis is often associated with ovarian teratoma (OT). The best management of anti-NMDAR encephalitis patients with normal imaging studies (pelvic ultrasound/MRI) but clinically high risk of OT (e.g., female, adult, black) is unclear. We report on the surprising diagnostic quest in a young black woman with anti-NMDAR encephalitis, in whom invasive procedures could finally disclose two OTs that were hidden from the initial non-invasive diagnostics. CASE REPORT: The patient presented with a one-week history of psychotic symptoms, developing oro-facial dyskinesia, seizures and coma, eventually requiring mechanical ventilation. NMDA-receptor antibodies were positive in serum and cerebrospinal fluid. Pelvic MRI and transabdominal ultrasound were normal. Exploratory laparoscopy was also unremarkable at first, but due to a suspicious echogenic mass (15 mm) in the right ovary on perioperative transvaginal ultrasound, an ovarian incision was performed which led to the detection of a first OT and its removal via ovarian-preserving cystectomy. Following a severe therapy-refractory clinical course despite aggressive immunotherapy and tumor removal, 6 months later bilateral oophorectomy was performed as ultima ratio, disclosing a second micro-OT (6 mm) in the left ovary. Unfortunately, the patient has not improved clinically yet. CONCLUSIONS: In therapy-refractory anti-NMDAR encephalitis with high risk of OT, small and bilateral OTs hidden from primary non-invasive diagnostics should be considered, which may trigger further invasive diagnostic procedures.

Cystic lymph node metastasis of papillary thyroid cancer: clinical facts.

BACKGROUND: The therapy planning for cystic cervical lesions is dizzying. Although it is mostly a benign disease, it can also be a cystic lymph node metastasis with the origin of papillary thyroid cancer (PTC). METHODS: Included were all patients with histological confirmed PTC, who underwent a thyroid resection from January 2012 to December 2017 (N.=680). Analyzed were demographic data including family history and radiation exposure, preoperative workup including thyroid ultrasound and laboratory test of the TSH value complimented by fine-needle aspiration in case of suspected malignancy, and clinicopathologic features. This study aimed to specify preoperative findings and patients' clinical presentation with cystic lymph node metastasis of PTC. RESULTS: In 0.7% (5/680) of all patients with PTC a cystic cervical lesion was histologically confirmed as cystic lymph node metastasis. Preoperatively, only two of these patients were suspected of lymph node metastasis with unknown origin. In three patients, the resected cystic lymph node metastases were the only lymphatic metastasis. Interestingly 80% (4/5) of the patients suffered from papillary microcarcinoma (MPTC). CONCLUSIONS: Cervical cystic lesions may be challenging in diagnostics and therapy. Although the recommended thyroid ultrasound may detect no pathological findings, a papillary microcarcinoma can be the primary tumor.

Double Positivity for HPV DNA/P16INK4a Does Not Influence Survival of Patients With Oral Squamous Cell Carcinoma.

BACKGROUND/AIM: We investigated the prevalence of human papillomavirus (HPV) in a prospective cohort of patients with squamous cell carcinoma of the oral cavity (OSCC) using both p16INK4a and HPV DNA, i.e., double positivity, as a definition criterion. Additionally, we examined the association of HPV with survival. PATIENTS AND METHODS: Samples from 280 OSCC patients were analyzed for HPV-positivity using p16INK4a immunohistochemistry (IHC) and in situ hybridization (ISH)/LCD arrays, for HPV low and high-risk types. Only patients positive for both p16INK4a and HPV DNA were considered as HPV-positive. Survival probabilities and 95% confidence intervals were estimated using the Kaplan-Meier method. Cox proportional hazards models were used to assess HPV association with disease-free survival (DFS), cause-specific survival (CSS) and overall survival (OS) in a competing risks scenario. RESULTS: Specimen from 30 (10.7%) patients were p16+ and HPV DNA+, while 31 (11.0%) were either p16+ or HPV DNA+ only. OS probabilities at five years for HPV-positive and -negative groups were 50.9% (35.4%-73.1%) and 52.9% (47.0%-59.5%), respectively. HPV double positivity influenced neither OS, CSS nor DFS: HR=0.84 (0.43-1.63), 1.64 (0.76-3.54) and 1.13 (0.55-2.35), respectively. CONCLUSION: In contrast to oropharyngeal cancer, the prevalence of HPV in OSCC is low and the presence of HPV does not influence survival outcomes. Hence, there is no evidence to support a parallel transfer of therapy regimen for HPV-positive OPC to OSCC, in terms of therapy de-escalation and/or vaccination.

Machine learning methods for automated classification of tumors with papillary thyroid carcinoma-like nuclei: A quantitative analysis.

When approaching thyroid gland tumor classification, the differentiation between samples with and without "papillary thyroid carcinoma-like" nuclei is a daunting task with high inter-observer variability among pathologists. Thus, there is increasing interest in the use of machine learning approaches to provide pathologists real-time decision support. In this paper, we optimize and quantitatively compare two automated machine learning methods for thyroid gland tumor classification on two datasets to assist pathologists in decision-making regarding these methods and their parameters. The first method is a feature-based classification originating from common image processing and consists of cell nucleus segmentation, feature extraction, and subsequent thyroid gland tumor classification utilizing different classifiers. The second method is a deep learning-based classification which directly classifies the input images with a convolutional neural network without the need for cell nucleus segmentation. On the Tharun and Thompson dataset, the feature-based classification achieves an accuracy of 89.7% (Cohen's Kappa 0.79), compared to the deep learning-based classification of 89.1% (Cohen's Kappa 0.78). On the Nikiforov dataset, the feature-based classification achieves an accuracy of 83.5% (Cohen's Kappa 0.46) compared to the deep learning-based classification 77.4% (Cohen's Kappa 0.35). Thus, both automated thyroid tumor classification methods can reach the classification level of an expert pathologist. To our knowledge, this is the first study comparing feature-based and deep learning-based classification regarding their ability to classify samples with and without papillary thyroid carcinoma-like nuclei on two large-scale datasets.