Tyrosine kinase inhibitor toxicities: A society of gynecologic oncology review and recommendations.

OBJECTIVE: Oral tyrosine kinase inhibitors (TKIs) have new indications for treatment in gynecologic malignancies. These targeted drugs have both unique and overlapping toxicities, which require careful attention and management. New combination therapies with immune-oncology agents have demonstrated promise in endometrial cancer. This review examines common adverse events associated with TKIs and provides readers with an evidence-based review on current uses and strategies for the management of these medications. METHODS: A comprehensive review of the medical literature on TKI use in gynecologic cancer was undertaken by a committee approach. Details of each drug, its molecular target, and relevant data on both clinical efficacy and side effects were compiled and organized for clinical use. Information on drug-related secondary effects and management strategies for specific toxicities, including dose reduction and concomitant medications, were gathered. RESULTS: TKIs can potentially offer improved response rates and durable responses for a group of patients who were previously without an effective standard second-line therapy. The combination of lenvatinib and pembrolizumab represents a more targeted approach to the drivers of endometrial cancer; however, there remains significant drug-related toxicity, and thus dose reduction and dose delay are frequently required. Toxicity management requires frequent check-ins and management strategies to help patients find the highest tolerable dose. TKIs are expensive and patient financial toxicity is as critical a measure of a drug's utility as any drug side effect. Many of these drugs have patient assistance programs, which should be fully utilized to minimize cost. CONCLUSIONS: Future studies are needed to expand the role of TKIs into new molecularly driven groups. Attention to cost, durability of response, and long-term toxicity management is needed to ensure all eligible patients have access to treatment.

Facilitated referral pathway for genetic testing at the time of ovarian cancer diagnosis: uptake of genetic counseling and testing and impact on patient-reported stress, anxiety and depression.

BACKGROUND: Timely genetic testing at ovarian cancer diagnosis is essential as results impact front line treatment decisions. Our objective was to determine rates of genetic counseling and testing with an expedited genetics referral pathway wherein women with newly-diagnosed ovarian cancer are contacted by a genetics navigator to facilitate genetic counseling. METHODS: Patients were referred for genetic counseling by their gynecologic oncologist, contacted by a genetics navigator and offered appointments for genetic counseling. Patients completed quality of life (QoL) surveys immediately pre- and post-genetic assessment and 6 months later. The primary outcome was feasibility of this pathway defined by presentation for genetic counseling. RESULTS: From 2015 to 2018, 100 patients were enrolled. Seventy-eight had genetic counseling and 73 testing. Median time from diagnosis to genetic counseling was 34 days (range 10-189). Among patients who underwent testing, 12 (16%) had pathogenic germline mutations (BRCA1-7, BRCA2-4, MSH2-1). Sixty-five patients completed QoL assessments demonstrating stress and anxiety at time of testing, however, scores improved at 6 months. Despite the pathway leveling financial and logistical barriers, patients receiving care at a public hospital were less likely to present for genetic counseling compared to private hospital patients (56% versus 84%, P = 0.021). CONCLUSIONS: Facilitated referral to genetic counselors at time of ovarian cancer diagnosis is effective, resulting in high uptake of genetic counseling and testing, and does not demonstrate a long term psychologic toll. Concern about causing additional emotional distress should not deter clinicians from early genetics referral as genetic testing can yield important prognostic and therapeutic information.

Eimeria bovis-induced modulation of the host cell proteome at the meront I stage.

The proteome of Eimeria bovis meront I-carrying host cells was analyzed by two-dimensional gel electrophoresis (2DE) at 14 days p.i. and compared to non-infected control cells. A total of 221 protein spots were modulated in their abundance in E. bovis-infected host cells and were subsequently analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectometry (MALDI-TOF-MS). These analyses identified 104 proteins in total with 25 host cell proteins being up-regulated and 79 proteins being down-regulated in E. bovis-infected host cells. Moreover, 20 newly expressed proteins were identified exclusively in E. bovis-infected host cells and were most likely of parasite origin. Parasite-induced differences in protein abundance concerned distinct functional categories, with most proteins being involved in host cell metabolism, cell structure, protein fate and gene transcription. Some of the modulated molecules also indicated regulatory processes on the level of host cell stress response (HSP70, HSP90), host cell apoptosis (caspase 8) and actin elongation/depolymerization (α-actinin-1, gelsonin, tropomodulin-3, transgelin). Since merozoites I were already released shortly after cell sampling, the current data reflect the situation at the end of first merogony. This is the first proteomic approach on E. bovis-infected host cells that was undertaken to gain a rather broad insight into Eimeria-induced host cell modulation. The data processed in this investigation should provide a useful basis for more detailed analyses concerning Eimeria-host cell interactions.

Eimeria bovis meront I-carrying host cells express parasite-specific antigens on their surface membrane.

Host immune responses conducted against antigens of Eimeria bovis are key factors for the development of protective immunity against this protozoan disease. In this study we investigated the expression of E. bovis-derived antigens on the host cell surface membrane during E. bovis first merogony in vitro. Host cells carrying E. bovis-meront I stages expressed E. bovis host cell surface antigens (EbHCSAg) on their surface membrane which were recognised by hyperimmune sera of calves and by sera from rats immunized with E. bovis merozoites I, when tested by indirect immune fluorescent antibody test (IIFAT), laser scanning confocal microscopy (LSCM) and immune electron microscopy. Expression of EbHCSAg on permissive host cells was earliest detected 7 days p. i., thus coinciding with the onset of the parasite replication. Membrane-associated EbHCSAg were removed from infected host cells by proteinase K, partially by Triton X-100, Triton X-114 and Triton X-405, but not by 1 M NaCl, CHAPS or phospholipase C treatment. Antibodies, affinity-purified on paraformaldehyde/glutardialdehyde (PAGA)-fixed E. bovis meront I-infected bovine host cells bound to the surface meront I-carrying cells and to merozoites I (IIFAT, LSCM) but, in contrast to untreated sera, not to sporozoites. When tested on methanol-fixed merozoites I and sporozoites by IIFAT, affinity-purified antibodies bound to structures in the apical complex area of merozoites I, but not to sporozoites, whilst untreated sera caused diffuse labelling of internal structures of both parasite stages. Immune electron microscopy demonstrated binding of affinity-purified antibodies to micronemes and dense granules of merozoites I. Although the function of EbHCSAg is still unknown, results of this study might suggest an involvement in the development of protective immunity against E. bovis infections.

Fluorescent Eimeria bovis sporozoites and meront stages in vitro: a helpful tool to study parasite-host cell interactions.

A fluorescence-based technique was established to trace intracellular sporozoites of Eimeria bovis for tests on gliding motility, invasion, replication and quantification of infection rates in cultured bovine umbilical vein endothelial cells (BUVEC) by laser scanning confocal microscopy and flow cytometry (FCM) analyses. Employing the fluorescent dye 5(6)-carboxyfluorescein diacetate succinimidyl ester (CFSE), we determined its effects on sporozoites at various concentrations and duration of staining. More than 98% of sporozoites were labelled with the dye at a concentration of 2.5 muM. Staining was predominantly found in refractile bodies and presumptive micronemes. Upon infection of BUVEC, CFSE-labelled sporozoites developed into fluorescent immature macromeronts, which were traceable inside the cells until 22 days postinfection (p. i.). Consistent with a peripheral localisation of the fluorescence signal in macromeronts merozoites released from these lacked detectable fluorescence. As example of use, a multicolour FCM approach for the simultaneous determination of E. bovis infection and host cell surface molecule expression was established. The approach proved suitable to quantify major histocompatibility complex (MHC-I) and MHC-II expression, thereby clearly distinguishing between infected and uninfected BUVEC up to day 14 p. i. In conclusion, CFSE labelling of E. bovis sporozoites facilitates monitoring of intracellular stages in vitro and will be a highly useful tool for studying host cell responses towards parasite invasion.

Photoreceptor morphogenesis in the Drosophila compound eye: R1-R6 rhabdomeres become twisted just before eclosion.

The photosensitive microvilli of Drosophila photoreceptors R1-R6 are not aligned in parallel over the entire length of the visual cells. In the distal half of each cell, the microvilli are slightly tilted toward one side and, in the proximal half, extremely toward the opposite side. This phenomenon, termed rhabdomere twisting, has been known for several decades, but the developmental and cell biological basis of rhabdomere twisting has not been studied so far. We show that rhabdomere twisting is also manifested as molecular polarization of the visual cell, because phosphotyrosine-containing proteins are selectively partitioned to different sides of the rhabdomere stalk in the distal and proximal sections of each R1-R6 photoreceptor. Both the asymmetrical segregation of phosphotyrosine proteins and the tilting of the microvilli occur shortly before eclosion of the flies, when eye development in all other aspects is considered to be essentially complete. Establishment of rhabdomere twisting occurs in a light-independent manner, because phosphotyrosine staining is unchanged in dark-reared wild-type flies and in mutants with defects in the phototransduction cascade, ninaE(17) and norpA(P24). We conclude that antiphosphotyrosine immunofluorescence can be used as a light microscopic probe for the analysis of rhabdomere twisting and that microvilli tilting represents a type of planar cell polarity that is established by an active process in the last phase of photoreceptor morphogenesis, just prior to eclosion of the flies.