This study provides independent support of EPHA5-rs7349683 and XKR4-rs4737264 as the first markers of risk of paclitaxel induced neuropathy. In addition, it suggests that other EPHA genes also involved in axonal guidance and repair following neural injury, as well as LIMK2 locus, may play an important role in the development of this toxicity. The identified SNPs could form the basis for individualised paclitaxel chemotherapy.

BackgroundIn ovarian cancer, massive intraperitoneal dissemination is due to exfoliated tumor cells in ascites. Tumor-initiating cells (TICs or cancer stem cells) and cells showing epithelial-mesenchymal-transition (EMT) are particularly implicated. Spontaneous spherical cell aggregates are sometimes observed, but although similar to those formed by TICs in vitro, their significance is unclear.MethodsCells freshly isolated from malignant ascites were separated into sphere samples (S-type samples, n=9) and monolayer-forming single-cell suspensions (M-type, n=18). Using western blot, these were then compared for expression of protein markers of EMT, TIC, and of cancer-associated fibroblasts (CAFs).ResultsS-type cells differed significantly from M-type by expressing high levels of E-cadherin and no or little vimentin, integrin-β3 or stem cell transcription factor Oct-4A. By contrast, M-type samples were enriched for CD44, Oct-4A and for CAF markers. Independently of M- and S-type, there was a strong correlation between TIC markers Nanog and EpCAM. The CAF marker α-SMA correlated with clinical stage IV. This is the first report on CAF markers in malignant ascites and on SUMOylation of Oct-4A in ovarian cancer.ConclusionsIn addition to demonstrating potentially high levels of TICs in ascites, the results suggest that the S-type population is the less tumorigenic one. Nanoghigh/EpCAMhigh samples represent a TIC subset which may be either M- or S-type, and which is separate from the CD44high/Oct-4Ahigh subset observed only in M-type samples. This demonstrates a heterogeneity in TIC populations in vivo which has practical implications for TIC isolation based on cell sorting. The biological heterogeneity will need to be addressed in future therapeutical strategies.

Metastatic cancers commonly activate adaptive chemotherapy resistance, attributed to both microenvironment‐dependent phenotypic plasticity and genetic characteristics of cancer cells. However, the contribution of chemotherapy itself to the non‐genetic resistance mechanisms was long neglected. Using high‐grade serous ovarian cancer (HGSC) patient material and cell lines, we describe here an unexpectedly robust cisplatin and carboplatin chemotherapy‐induced ERK1/2‐RSK1/2‐EphA2‐GPRC5A signaling switch associated with cancer cell intrinsic and acquired chemoresistance. Mechanistically, pharmacological inhibition or knockdown of RSK1/2 prevented oncogenic EphA2‐S897 phosphorylation and EphA2‐GPRC5A co‐regulation, thereby facilitating a signaling shift to the canonical tumor‐suppressive tyrosine phosphorylation and consequent downregulation of EphA2. In combination with platinum, RSK inhibitors effectively sensitized even the most platinum‐resistant EphA2high, GPRC5Ahigh cells to the therapy‐induced apoptosis. In HGSC patient tumors, this orphan receptor GPRC5A was expressed exclusively in cancer cells and associated with chemotherapy resistance and poor survival. Our results reveal a kinase signaling pathway uniquely activated by platinum to elicit adaptive resistance. They further identify GPRC5A as a marker for abysmal HGSC outcome and putative vulnerability of the chemo‐resistant cells to RSK1/2‐EphA2‐pS897 pathway inhibition.

Background: The aim of this study is to evaluate the impact of lymphovascular space invasion (LVSI) on the risk of lymph node metastases and survival in endometrioid endometrial adenocarcinoma. Material and methods: As regard the study design, this is a cohort study based on prospectively recorded data. Patients with endometrioid endometrial adenocarcinoma registered in the Swedish Quality Registry for Gynecologic Cancer 2010-2017 with FIGO stages I-III and verified nodal status were identified (n ¼ 1587). LVSI together with established risk factors, namely DNA ploidy, FIGO grade, myometrial invasion and age, were included in multivariable regression analyses with lymph node metastases as the dependent variable. Associations between the risk factors and overall and relative survival were included in multivariable models. Estimates of risk ratios (RR), hazard ratios (HR), excess mortality rate ratios (EMR), and 95% confidence intervals (95% CI) were calculated. Results: The presence of LVSI presented the strongest association with lymph node metastases (RR ¼ 5.46, CI 3.69-8.07, p < .001) followed by deep myometrial invasion (RR ¼ 1.64, CI 1.13-2.37). In the multivariable survival analyses, LVSI (EMR ¼ 7.69, CI 2.03-29.10,) and non-diploidy (EMR ¼ 3.23, CI 1.25-8.41) were associated with decreased relative survival. In sub-analyses including only patients with complete para-aortic and pelvic lymphadenectomy and negative lymph nodes (n ¼ 404), only LVSI (HR ¼ 2.50, CI 1.05-5.98) was associated with a worsened overall survival. Conclusion: This large nationwide study identified LVSI as the strongest independent risk factor for lymph node metastases and decreased survival in patients with endometrioid adenocarcinomas. Moreover, decreased overall survival was also seen in patients with LVSI-positive tumors and negative lymph nodes, indicating that hematogenous dissemination might also be important.

The data in the Swedish Quality Register for Gynecologic Cancer are of adequate quality in order to be used as a basis for research and to evaluate possible differences in treatment, lead times and treatment results.

Heat shock protein 60 may identify groups of advanced serous ovarian cancer with different prognosis and treatment response.

We have here examined chemopotentiating effects of glycolysis inhibitor 2-deoxy-D-glucose (DG) in two epithelial ovarian carcinoma (EOC) cell lines and 17 freshly isolated ascitic EOC cell samples, and we identify low expression of the β-F1-ATPase involved in mitochondrial ATP production as a candidate marker for sensitivity to this strategy. Although in the majority of samples, DG per se did not induce apoptosis, cotreatment with DG potentiated apoptosis and total antiproliferative effects of cisplatin and, to a lesser degree, carboplatin. In the cell lines, combination treatment with DG and cisplatin or carboplatin at noninhibitory concentrations prevented posttreatment regrowth in drug-free medium over a total of 5 days. DG per se allowed complete recuperation in drug-free medium. The more platinum-resistant a cell line was, the more sensitive it was to potentiation by DG and showed higher glucose uptake, DG-sensitive lactate production, and lower β-F1-ATPase levels. In the ascitic samples, DG reduced the median IC 50 for cisplatin by 68% and, in the most sensitive samples, up to 90%, and DG-mediated potentiation correlated with low expression of β-F1-ATPase. By contrast, cisplatin sensitivity did not correlate with β-F1-ATPase levels. The findings validate targeting cancer cell glucose metabolism for potentiating platinum chemotherapy in EOC and indicate that reduced β-F1-ATPase/oxidative phosphorylation distinguishes cells that are amenable to this strategy.

BackgroundA deregulated energy metabolism is a hallmark of malignant disease that offers possible future targets for treatment. We investigated the prognostic value of the glycolytic enzymes glyceraldehyde 3-phosphate dehydrogenase (GAPDH) and pyruvate kinase type M2 (PKM2), mitochondrial β-F1-ATPase (ATP5B) and the bioenergetic cellular (BEC) index in advanced ovarian cancer.MethodsFresh tumor samples were prospectively collected from 123 patients undergoing primary surgery for suspected advanced ovarian cancer. Of these, 57 met the eligibility criteria; stage IIC-IV, serous or endometrioid subtype, specimens containing ≥ 50% tumor cells and patients receiving platinum-based chemotherapy. An adequate amount of mRNA could be extracted in all but one case, with a resultant study population of 56 patients. Eighty-six percent of cases had serous tumors, and 93% were grade 2–3. GAPDH, PKM2 and ATP5B mRNA- and protein expression was assessed by real-time PCR and immunohistochemistry. We estimated the association with platinum-free interval (PFI) and overall survival (OS) by Cox proportional hazards models. Median follow-up was 60 months.ResultsHigh GAPDH mRNA levels (HR 2.1, 95% CI 1.0-4.5) and low BEC-index (HR 0.47, 95% CI 0.23-0.95) were both independently associated with shorter PFI. Median PFI for patients with high GAPDH mRNA was 5.0 months compared to 10.1 months for low expression cases (p = 0.031). Similarly, median PFI for patients with low BEC-index based on mRNA was 5.3 months compared to 9.8 months for high BEC-index cases (p = 0.028).ConclusionsHigh GAPDH or low BEC-index mRNA expression indicate early disease progression in advanced serous ovarian cancer.