[Treatment of head and neck squamous cell carcinoma recurrences and distant metastases : Highlights of the 2019 ASCO Meeting]. / Therapie der rezidivierten und fernmetastasierten Plattenepithelkarzinome des Kopf-Hals-Bereichs : Highlights des ASCO-Meetings 2019.

BACKGROUND: The contributions presented at this year's ASCO conference on treatment of recurrent or metastatic head and neck squamous cell carcinoma (R/M-HNSCC) focused on systemic therapies, as in recent years. Two phase III studies-TPExtreme and Keynote-048-are expected to change clinical practice in first-line treatment of R/M-HNSCC. MATERIALS AND METHODS: Abstracts and presentations from this year's ASCO Annual Meeting on R/M-HNSCC were screened and checked for clinical relevance. RESULTS: TPExtreme, a randomized phase III trial, could show less toxicity and similar overall survival in patients treated with docetaxel, cisplatin, and cetuximab (TPEx regimen) compared to standard first-line therapy with the Extreme regimen (cisplatin, 5­fluorouracil [5-FU], cetuximab), albeit failing its endpoint of significantly improved survival. The randomized phase III Keynote-048 study could show a significant survival benefit in all patients treated with pembrolizumab, 5­FU, and cis-/carboplatin compared to Extreme. When selected patients (PD-L1 CPS ≥1 and ≥20) were treated with pembrolizumab monotherapy, they showed increased overall response rates in contrast to patients treated with Extreme. CONCLUSION: Based on the results of Keynote-048, pembrolizumab ± chemotherapy gained FDA approval as first-line treatment for R/M-HNSCC in the USA. Approval in Europe is expected soon and will probably have a strong impact on clinical routine.

Tumor volume as a predictive parameter in the sequential therapy (induction chemotherapy) of head and neck squamous cell carcinomas.

PURPOSE: Tumor volume in locally advanced head and neck squamous cell carcinomas (LAHNSCC) treated by induction chemotherapy (ICT) and followed by radiochemotherapy (RCT) was measured. The presence of potential correlation of initial tumor volume and volume reduction after ICT and RCT with remission status, overall survival (OS) and disease-free survival (DFS) were investigated. Furthermore, reliability of approximation of the tumor volume relying on its diameter to manual three-dimensional measurement was assessed. METHODS: Data of patients with LAHNSCC treated by ICT consisting of docetaxel, cisplatin, and 5-fluorouracil (TPF) followed by definite RCT were retrospectively analyzed. The tumor volume was calculated slice-by-slice in contrast-enhanced CT or MRI before and after ICT as well as after complete treatment. The volume was compared to radiologic remission status, correlated with OS and DFS, and to volume estimation using tumor diameter. RESULT: 65 patients were included. Primary tumor volume did not correlate with complete remission rate (CR) after ICT and RCT, OS or DFS. The change in tumor volume between baseline imaging and post-RCT had a significant impact on OS (p = 0.026) and DFS (p = 0.028). The agreement between tumor volume and radiologic remission was 72.14%. CONCLUSION: The initial tumor volume had no influence on CR, OS or DFS. A severe response to ICT did not predict a powerful RCT outcome. The change in tumor volume post-RCT had an impact on OS and DFS. Tumor volume estimation using its diameter seems to be a reliable method.

[Treatment of head and neck squamous cell carcinoma recurrences and distant metastases : Highlights of the 2018 ASCO meeting]. / Therapie der rezidivierten und fernmetastasierten Plattenepithelkarzinome des Kopf-Hals-Bereichs : Highlights des ASCO-Meetings 2018.

This year, the treatment of patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M-HNSCC) was mainly dominated by immunotherapy. The corresponding studies are presented in another article. Beside this, results of phase II studies in particular were presented at the ASCO Annual Meeting, in which-as in recent years-new drugs (monoclonal antibodies, small molecules) played a major role. Furthermore, a clinical scoring system for prognosis evaluation in R/M-HNSCC patients was presented and the influence of HPV status on survival in this patient cohort was investigated. The studies presented herein reflect the different drug-based treatment concepts in R/M-HNSCC and represent the variety of therapeutic approaches in the recurrent and metastatic setting.

[Treatment of head and neck squamous cell carcinoma recurrences and distant metastases : Highlights of the ASCO Meeting 2016]. / Therapie der rezidivierten und fernmetastasierten Kopf-Hals-Tumoren : Highlights des ASCO-Meetings 2016.

This year particularly phase II studies were presented at the 2016 ASCO Annual Meeting, in which new drugs (monoclonal antibodies, small molecules) were investigated in patients with recurrent or metastatic head and neck squamous cell carcinoma (R/M-HNSCC). Notably, there was a great number of studies investigating carcinoma of the nasopharynx. The studies presented in this article summarize the different therapeutic concepts in the treatment of R/M-HNSCC and represent the variety of therapeutic approaches in the recurrent and metastatic setting.

[Is (chemo)radiotherapy really the future standard in the treatment of oropharyngeal carcinoma?]. / Ist Radio(chemo)therapie wirklich der zukünftige Standard für die Behandlung von Oropharynxkarzinomen?

Treatment of patients with oropharyngeal squamous cell carcinoma (OPSCC) requires interdisciplinary collaboration. Besides oncologic control, organ and function preservation are important priorities. One treatment option is primary concomitant chemoradiotherapy (CRT), particularly for locally advanced head and neck cancer. Another option is sequential CRT, where induction chemotherapy may be followed either by radiation alone or by CRT. An important aspect of these modalities is the development of functional sequelae with regards to swallowing as a direct consequence of radiogenic fibrosis, as well as tissue ctoxicity associated with cisplatin-based chemotherapy. Conventional open surgical approaches are being increasingly replaced by transoral surgical modalities with less treatment-related morbidity. As a further, equally important goal of appropriately indicated surgery, adjuvant (C)RT may be omitted or the dose significantly reduced. The advantages of primary surgery over primary CRT may be less obvious in cases still requiring adjuvant treatment, although not necessarily completely eliminated. For patients with human papillomavirus (HPV)-driven OPSCC, it is important to note that primary surgery may provide comparable or even increased survival benefit. To date, there is no evidence for a clear advantage of primary CRT over primary surgery in this group. In these cases, a de-escalated treatment package may be the preferred option. Here, the application of radioimmunotherapy as well as a reduced radiation dose may minimize long-term treatment-related morbidities.

[Treatment of head and neck squamous cell carcinoma recurrences and distant metastases: Highlights of the ASCO Meeting 2015]. / Therapie der rezidivierten und fernmetastasierten Plattenepithelkarzinome des Kopf-Hals-Bereichs: Highlights des ASCO-Meetings 2015.

This year also saw a great number of phase II and III studies presented at the ASCO Annual Meeting, in which new drugs (monoclonal antibodies, small molecules) were investigated as an alternative to or in combination with established mono- and polychemotherapy in patients with recurrences or distance metastases from head and neck squamous cell carcinoma (R/M-HNSCC). The studies now presented here describe the different concepts being applied to drug-based treatment of R/M-HNSCC and illustrate the variety of therapeutic approaches to treatment of recurrences and metastases.

Milk lactoferrin in heifers: influence of health status and stage of lactation.

The objective of the current study was to analyze the variations in lactoferrin (LF) concentrations in primiparous cows with intramammary infection and to study how the lactation stage affects these variations. In addition, we aimed to study the potential of the LF concentration in early lactation as a predictive factor for future infections. To accomplish this goal, a longitudinal analysis was performed for 96 primiparous cows. Milk samples were collected each month from individual quarters, and the LF concentration was determined for each sample. Criteria that included both somatic cell count (SCC) and a microbiological analysis were used to assess the health status of the quarters. Of the diseased quarters (SCC >200,000 or positive for pathogen isolation, or both), 62% corresponded to nonspecific mastitis (SCC >200,000 but microbiologically negative) and 25% corresponded to the category "presence of bacterial growth" (SCC <200,000 but microbiologically positive). Diseased quarters showed increased concentrations of LF compared with healthy quarters. However, this increase was greater during the first days of lactation compared with later periods. Kaplan-Meier analysis of time free of infection demonstrated that quarters with LF concentrations at early lactation (3-10d in milk) greater than 0.1mg/mL are more likely to become infected during the following lactation compared with quarters with lower LF concentrations in early lactation. The results support that LF plays a relevant role in combating intramammary infection, particularly during the first days of lactation. In addition, we present evidence of the potential use of LF as a predictive marker of future infections in the individual quarters of dairy heifers.

Antimicrobial activity of bovine ß-lactoglobulin against mastitis-causing bacteria.

Bovine mastitis is one of the most economically deleterious diseases affecting dairy herds and results from an infection of the udder by pathogenic microorganisms such as Staphylococcus aureus, Streptococcus uberis, and Escherichia coli. The mammary gland is capable of preventing and combating bacterial infection by means of a complex network of innate and adaptive immune mechanisms. Lactoferrin is an 86-kDa protein with antibacterial activity that plays a role in the mammary gland's defense against infection. ß-Lactoglobulin (ß-LG) is an 18-kDa protein that is present in most mammals but is notably absent in humans, rodents, and lagomorphs. Different genetic variants of this protein exist, with ß-LG A and ß-LG B being the most common. In spite of being well studied, the biological function of ß-LG is not thoroughly understood, and most noticeably, no reports exist on the effects of the native protein on bacterial growth. Hence, the objective of this study was to assess the potential antibacterial activity of ß-LG against mastitis agents. To do this, we purified ß-LG from normal bovine milk using a mild, nondenaturing method and performed in vitro growth inhibition assays with Staph. aureus, E. coli, and Strep. uberis. ß-Lactoglobulin inhibited the growth of Staph. aureus and Strep. uberis but had no effect on E. coli. The antimicrobial activity against Staph. aureus and Strep. uberis was concentration dependent and was elicited by the intact protein because Tricine-sodium dodecyl sulfate-PAGE and analytical gel filtration chromatography did not reveal the presence of short degradation peptides. Analysis of the genetic variants of ß-LG showed that ß-LG A has higher inhibitory activity against Staph. aureus and Strep. uberis than ß-LG B. Coincubation of ß-LG and lactoferrin resulted in an augmented antibacterial activity against Staph. aureus, suggesting an additive effect of the proteins. This result, along with the proteins' complementary spectrum of action, suggests that ß-LG and lactoferrin may complement each other in the mammary gland's defenses against bacterial infection.

Relationship between milk lactoferrin and etiological agent in the mastitic bovine mammary gland.

Bovine mastitis is one of the most deleterious diseases for dairy herds and is mainly caused by contagious and environmental bacterial pathogens. Among contagious bacteria, Staphylococcus aureus is the most prevalent, whereas the main environmental mastitis pathogens are Streptococcus uberis and Escherichia coli. Bovine lactoferrin (bLF) is an approximately 80-kDa glycoprotein present in milk that participates in the innate response of the mammary gland against bacterial infection. The objectives of the current study were to analyze potential changes in bLF milk concentration, which would constitute a response of the mammary gland toward mastitis induced by different etiologic agents, and to evaluate a possible relation between this response and pathogen susceptibility to bLF. Microbiology analysis and bLF quantification in milk from different bovine mammary gland quarters were performed. Infected quarters presented greater concentrations of bLF compared with those from microbiologically negative quarters. Analysis of individual pathogen contributions showed that most of this increase was attributable to Strep. uberis intra-mammary infection. The ability of mammary gland cells to synthesize bLF in response to Strep. uberis challenge was demonstrated by immunodetection of the protein in in vitro infection experiments. Susceptibility of Strep. uberis, E. coli, and Staph. aureus to the antimicrobial activity of bLF was determined by growth inhibition assays conducted with 4 different isolates of each species. Whereas Staph. aureus and E. coli were shown to be susceptible to this protein, Strep. uberis appeared to be resistant to the antimicrobial activity of bLF. Molecular typing of the 4 Strep. uberis isolates used throughout this study showed that this result was representative of the species and not exclusive of a particular strain. Results presented herein suggest that different bacteria species may elicit different mammary gland responses mediated by bLF secretion and that Strep. uberis has probably adapted to this immune reaction by developing resistance to bLF inhibitory action.

Effects of exercise on muscle metabolites and sarcoplasmic reticulum function in ovariectomized rats.

The relationships between exercise and metabolites as well as between exercise and sarcoplasmic reticulum function were studied in gastrocnemius muscle of ovariectomized-trained rats. Prolonged moderate-intensity exercise, treadmill up-hill run for 90 min with a 10 degree incline, decreased the muscle glycogen content. Exercise until exhaustion further lowered the glycogen concentration to 13% of the control, together with a significant decrease of ATP and glucose-6-phosphate concentrations. Also, Ag+-induced Ca2+ release, measured in whole muscle homogenate, showed a 30% reduction on exhaustion, while Ca2+ uptake was unaffected by this exercise. ATPase activities, of both homogenate and SR vesicles, and Ca2+ transport in the latter preparation were not altered on exhaustion. It could be concluded from these results that muscular fatigue in ovariectomized rats after aerobic exercise is caused by the change in energy supply and Ca2+ release from the SR, this latter possibly due to metabolites generated by the exercise.

Exercise and ovarian steroid hormones: their effects on mitochondrial respiration.

The effect of exercise on mitochondria respiration was studied in gastrocnemius muscle of ovariectomized rats, pseudopregnant rats, and estrous rats. The estrous cycles were followed by vaginal smears. Rats were made pseudopregnant (PSP) by 45 s cervical stimulation with a glass rod on the day of estrous. The treadmill protocol (21 m/min, 10 grade uphill) induced a significant decrease in state 3 oxygen consumption (oxidative phosphorylation) in estrous (0.26 +/- 0.02 vs. 0.49 +/- 0.05 microatoms O min(-1) mg protein(-1)) and ovariectomized rats (0.18 +/- 0.03 vs. 0.40 +/- 0.03 microatoms O min(-1) mg protein(-1)). In contrast, pseudopregnant and progesterone-treated ovariectomized rats did not decrease state 3 nor state 4 respiratory rates. These results show that the effect of exercise on mitochondria respiration does vary according to the hormonal status.

Relaxin has a minor role in rat mammary gland growth and differentiation during pregnancy.

Growth and differentiation of mammary gland is associated with numerous hormones and a variety of cell-cell, cell-matrix interactions. This study addressed the role of relaxin (Rlx) on these processes. Morphologic and biochemical changes that occur throughout the second half of pregnancy are reported. Temporal patterns and spatial distributions of markers useful to evaluate proliferation, secretion, and collagen remodeling were established. To evaluate the role of Rlx, an ablation/replacement animal model was used. Considering Rlx secretion pattern, two periods were selected: d 11 through d 13, and d 20 through d 23. In the stroma, the extracellular compartment showed changes associated with the lack of Rlx. Collagen remodeling within the lobuloalveolar structure, measured by a significant increase in collagen birefringence, decreased at d 12, d 21, and d 22. Parenchymal structures were less sensitive to the absence of Rlx than stroma. Epithelial cell proliferation was lower in Rlx-deficient rats only at d 12, and alpha-lactalbumin expression decreased at d 21 and d 22. Both lobuloalveolar diameter and percentage of area occupied by these structures showed no changes. In the absence of Rlx, some of the studied markers showed statistically significant differences in scattered days; these do not make clear trends. No differences were found on d 23 on any of the studied parameters suggesting that compensatory mechanisms might be activated to overcome the effects of the absence of Rlx. Unlike the critical role of Rlx either in uterine cervix dilation or in nipple development during rat pregnancy, Rlx had a minor role in growth and differentiation of rat mammary gland.

Role of receptors for epidermal growth factor and insulin-like growth factors I and II in the differentiation of rat mammary glands from lactogenesis I to lactogenesis II.

In addition to ovarian steroids and lactogenic hormones from the placenta and pituitary, growth factors control the growth and differentiation of mammary glands. Lactogenesis II at the end of pregnancy is under the control of progesterone. Ovariectomy results in a significant decrease in the number of receptors for epidermal growth factor (EGF) and insulin-like growth factor I (IGF-I) and an increase in IGF-II binding sites in mammary gland acini of rats, without affecting the affinity for their respective ligand. Although concentrations of EGF, IGF-I and IGF-II receptors are regulated by oestradiol and progesterone, replacement treatment with ovarian steroids after ovariectomy showed that receptor concentrations do not mediate the restraint on lactogenesis. Progesterone treatment, which inhibits the onset of lactogenesis II, did not restore EGF receptor concentrations to control values, and the presence of oestradiol was required to reverse the effect of ovariectomy. Oestradiol, which potentiates the effect of ovariectomy on milk synthesis, increases IGF-I receptor concentrations. IGF-II receptor concentrations, after the different steroid treatments, were consistent with the steroid effect on milk synthesis. The changes observed in the concentrations of these growth factor receptors at the onset of mammary gland secretion are not considered to affect the progesterone block to lactogenesis II, but rather are a consequence of the shift of the hormonal and, hence, physiological status of the gland.

In vivo regulation of the steroidogenic activity of rat luteal cells by insulin.

The aim of the present study was to determine the long-term effects of insulin treatment on luteal cell function. For this purpose, superovulated prepubertal rats were treated with insulin (group I) or vehicle (group C) for 9 days. Serum progesterone (P4) levels were increased in the insulin-treated group (55 +/- 10 vs 134 +/- 31 ng/ml, P < 0.05). Isolated luteal cells were incubated 3 h, and P4 and 20 alpha-hydroxy-progesterone (20 alpha-OH-P) were measured in the incubation media. A decrease in P4 levels and an increase in 20 alpha-OH-P values [P4 (ng/ml): C = 26.6 +/- 0.3; I = 20 +/- 2; 20 alpha-OH-P (ng/ml): C = 62 +/- 2; I: 120 +/- 7; P < 0.01] were observed in group I. In addition, progestagen (P4 + 20 alpha-OH-P) levels were higher in group I (C = 88 +/- 2; I = 140 +/- 9 ng/ml; P < 0.001). When cytochrome P450scc contents were measured by immunoblotting, a marked increase was observed in luteal cells obtained from group I. LH receptor numbers were decreased in luteal cells isolated from group I (C = 388,834 +/- 14,146; I = 303,057 +/- 13,392 sites/cell; P < 0.001) with a concomitantly diminished LH responsiveness. It is concluded that in vivo treatment of superovulated rats with insulin increases luteal progestagen production by increasing the content of cytochrome P450scc.

Regulation of the cholesterol ester cycle and progesterone synthesis by juvenile hormone in MA-10 Leydig tumor cells.

We had previously reported that juvenile hormone III (JH III) and the JH analogue 2-(4-phenoxy phenoxy)-ethoxytetrahydropyran exert inhibitory effects on progesterone synthesis by blocking cAMP production in hCG-stimulated MA-10 Leydig tumor cells. In the present study, the effects of JH analogue upon the biosynthetic pathway of progesterone synthesis have been examined. Our results demonstrated that JH analogue inhibited progesterone production even in the presence of 20-hydroxycholesterol or 25-hydroxycholesterol. Furthermore, although JH analogue inhibited pregnenolone production in hCG-stimulated MA-10 cells the activity of the 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) was unaffected. These data suggest that JH analogue might inhibit the steroidogenic pathway in Leydig tumor cells by inhibiting the activity of the cholesterol side chain cleavage (CSCC) enzymatic complex. The JH analogue was also evaluated for inhibitory actions on cholesterol availability. An important effect of this compound was the interference with the cellular process of plasma membrane cholesterol internalization. Moreover, JH analogue inhibited not only the use of cholesterol ester for steroid biosynthesis under Bt2cAMP stimulation, but also the cholesterol ester hydrolase (CEH) activity in MA-10 Leydig tumor cells.

Effects of juvenile hormone on mammalian steroidogenesis.

The effects of juvenile hormone-III (JH-III) and the JH analogue 2-(4-phenoxyphenoxy)-ethoxyte-trahydropiran on testicular steroidogenesis were studied. By using cultured MA-10 Leydig tumor cells as a model, these compounds were found to be potent inhibitors of LH/hCG steroidogenic action in a dose-dependent manner. Scatchard plot analysis of the binding data indicated that the JH analogue did not significantly alter the affinity nor the number of hCG binding sites, as well as GTP binding to plasma membranes. JH analogue inhibited the stimulatory action of both cholera toxin and forskolin on cAMP production and the concomitant steroidogenic response. JH analogue inhibited (Bu)2cAMP-stimulated progesterone synthesis, indicating that a process downstream to the adenylyl cyclase in the steroidogenic pathway is also affected.

Prostaglandin F-2 alpha receptors in corpora lutea of pregnant rats and relationship with induction of 20 alpha-hydroxysteroid dehydrogenase.

Luteal receptors for PGF-2 alpha in the pregnant rat were characterized. No changes in the Kd were found during pregnancy, whereas capacity increased to a maximum on Day 19, decreasing thereafter. The decrease in binding sites seen from Days 20 to 22 may be due to down regulation of the receptor by its ligand, since it was prevented by inhibition of PG synthesis by indomethacin treatment. Likewise, in-vivo treatment with PGF-2 alpha reduced the apparent number of PG binding sites. PG receptor concentration seems to be modulated by oestrogens since an increment was found on Day 19, associated with the known increase in plasma oestradiol concentrations, and since receptor concentration on Day 16 was significantly increased by oestradiol benzoate. The uterus also had a negative influence on the appearance of the PG receptor, since hysterectomy on Day 16 increased the number of binding sites on Day 18. However, receptor concentration and 20 alpha-hydroxysteroid dehydrogenase induction by hysterectomy was not affected by indomethacin, indicating that these events are probably not related to prostaglandin withdrawal. However, treatment with hCG, which diminishes enzyme induction by hysterectomy, did not produce changes in receptor concentration. The present results suggest that PGF-2 alpha, acting through a specific receptor site, is the physiological luteolytic signal. The consequence of its receptor binding seems to be the blockade of a gonadotrophic stimulus, which in turn determines (1) the decrease in progesterone synthesis and (2) the induction of 20 alpha-hydroxysteroid dehydrogenase.

Hormonal regulation of casein synthesis at the end of pregnancy.

Ovariectomy or ovariohysterectomy on day 18 of pregnancy augmented mammary beta-casein content 28 h later. Progesterone injected immediately and 12 h after ovariectomy showed a clear inhibitory effect on casein synthesis. Estrogen induced a significant increase in mammary beta-casein content when injected 12 h after surgery. Treatment with CB-154 to prevent prolactin release did not affect the increase of casein induced by ovariectomy. When CB-154 was injected to ovariohysterectomized pregnant rats, significant reduction of casein synthesis was obtained. According to these findings, rat placental lactogen in the absence of prolactin and progesterone induces beta-casein synthesis. Therefore prolactin, ovarian and placental hormones interplay at the end of pregnancy for full expression of the mammary gland genome.

Gamma-glutamyltransferase activity in mammary gland of pregnant rats and its regulation by ovarian hormones, prolactin and placental lactogen.

Ovariectomy and ovariectomy plus hysterectomy on day 18 of pregnancy increased gamma-glutamyltransferase activity in the mammary gland. The withdrawal of progesterone and the subsequent release of prolactin are responsible for the rise in enzyme activity. Rat placental lactogen in the absence of prolactin and progesterone is able to induce gamma-glutamyltransferase activity.