The Effects of Adjuvant Chemoradiotherapy (CRT) on Myeloid-Derived Suppressor Cell (MDSC) Subsets in Glioblastoma (GBM)

PURPOSE/OBJECTIVE(S)

GBM continues to be a diagnosis with an exceedingly low survival rate despite standard therapy of resection followed by concurrent CRT. MDSC, immunosuppressive myeloid cells that aid immune system evasion by the tumor, expand during fractionated RT. To date, little is known about the effects of CRT on MDSC subsets. The goal of our pilot study is to compare peripheral blood MDSC subset frequency in patients (pts) undergoing CRT. We hypothesize that the pro-tumor, monocytic MDSC (M-MDSC) subset increases following CRT.

MATERIALS/METHODS

Pts over the age of 18 yo with a new diagnosis of GBM from a single institution participated in the study between 7/2022 -1/2023. Exclusion criteria included prior history of brain RT. Baseline peripheral blood samples were collected within one week prior to CRT start and post-CRT samples were collected within the last week of CRT. Peripheral blood mononuclear cells (PBMC) were isolated from whole blood and freshly stained for intracellular flow cytometric analyses. Total MDSC (singlet, viable, non-lymphocyte, CD11b+CD33+ HLA-DR- cells) and subsets (M-MDSC, granulocytic (G-MDSC), and early MDSC (eMDSC)) were identified. Percent frequency (%fx) of total and MDSC subsets as well as MDSC activation status (n = 3) (interleukin (IL)-10, transforming growth factor-β (TGF-β), interferon gamma (IFNγ)) was compared before and after CRT.

RESULTS

The average age of pts receiving CRT (n = 4) was 70 yo. Fractionated RT consisted of CF RT (n = 2), 6000 cGy in 30 fractions, and HF RT (n = 2), 4005 cGy in 15 fractions. All pts received concurrent chemotherapy with temozolomide. The %fx of MDSC of non-lymphocytes started at 29.2% prior to CRT and decreased to 9.9% at the end of CRT. The fold change of %fx of total MDSC in CF RT and HF RT was 0.39 and 0.29, respectively. The mean change in %fx of MDSC subsets before and after CRT are shown in Table 1. The mean %fx of TGF-β-expressing MDSC in all GBM pts increased by 3.5% after CRT. The mean IFNγ+ MDSC %fx for all GBM pts decreased after CRT from 24.2% to 16.2% with a corresponding decrease in geometric mean fluorescence intensity (GMFI). The mean %fx of IL-10+ MDSC decreased by 1.5% at the end of CRT with a decrease in GMFI from 5550 to 1806.

CONCLUSION

In this limited dataset of pts with GBM receiving standard of care adjuvant therapy, we identified an expansion in the eMDSC and decrease in the M-MDSC subsets. These early results suggest HF RT may promote immunity that is more supportive of anti-tumor function, with a lesser increase in fold change of total MDSC after CRT. A more detailed understanding of the effect of RT on myeloid subpopulations is essential to addressing immune suppression in pts with GBM.

Effect of External Beam Radiation Therapy (EBRT) and Brachytherapy (BT) on Circulating MDSC Populations in Patients Treated Definitively for Cervical Cancer

PURPOSE/OBJECTIVE(S)

The immunosuppressive function of myeloid derived suppressor cells (MDSCs) has been implicated in the regulation of immune responses against cancer. MDSCs have been associated with progression and poor response to therapy in various types of cancer, including cervical cancer. Radiation treatment (RT) alters immune cell populations within the tumor and is thought to augment antitumor responses. However, whether RT also recruits immunosuppressive MDSC populations is not well understood. Here, we investigate how circulating MDSC populations change in response to RT and if changes in MDSC frequency or subsets is predictive of RT responses in cervical cancer patients.

MATERIALS/METHODS

Newly diagnosed, treatment-naïve pts with locally advanced carcinoma of the cervix will be enrolled from July 2022 to July 2023. EBRT to the pelvis was delivered at a dose of 45 Gy in 25 fractions with a simultaneous integrated boost of 52-55 Gy to involved regional lymph nodes and parametria and concurrent weekly cisplatin. Gross tumor was boosted via interstitial or tandem ring BT (22.5-27.5 Gy) after completion of EBRT. Serial blood samples were collected prior to initiating therapy (T0), post-EBRT and pre-BT (T1), and one-month post-BT (T2). Treatment response was determined based on pre-treatment MRI compared to MRI post-EBRT. Peripheral blood mononuclear cells (PBMCs) were isolated from whole blood using density gradient centrifugation and stained for analysis via flow cytometry. MDSC populations were identified by Live/Dead-CD11b+CD33+HLA-DR- staining. MDSC subsets were further subdivided into granulocytic (G-, CD15+CD14-), monocytic (M-, CD15-CD14+), or early-MDSCs (e-, CD15-CD14-).

RESULTS

Blood samples were collected at indicated time points for four patients (FIGO stage IIA-IIB). Three had partial responses to chemoradiotherapy (CRT), while one had a complete response. All three patients with partial response had an increase in total frequency of circulating MDSCs in response to EBRT/BT (mean %fx MDSC 16.6 at T0 to 35.9 at T2), and an increase in total MDSCs in two of these patients occurred with EBRT alone. Interestingly, the patient that had a complete response had fewer MDSCs at T2 relative to T0 (35.8% at T0 to 27% at T2). Proportion of MDSC subsets varied considerably among the patients, and all had altered distribution of subsets in response to RT. G-MDSCs expanded the most to RT while M-MDSCs and e-MDSCs were less affected (mean fold change from T0 to T2 G-MDSC 4.75, M-MDSC 1.27, e-MDSC 0.942).

CONCLUSION

In this cohort of patients, an increase in MDSC frequency occurred after RT and altered subset distribution. Only the patient with a complete response had fewer total MDSCs following completion of CRT, suggesting further studies are needed to determine if circulating MDSCs could be a biomarker for treatment response to RT in cervical cancer.

A Challenging Yet Motivating Journey: The Experiences of Young Adult Parents With Serious Mental Health Conditions in the USA

In recent decades the average age of becoming a parent has increased, the rate of teen pregnancies has decreased, and a new developmental period of emerging adulthood is marked by diverse pathways into adulthood. Today, those who become parents in young adulthood (18-24 years old) and their children may be vulnerable to poor outcomes observed in teen parents (13-19 years old) of previous generations. Young adults with serious mental health conditions (SMHC) who encounter additional challenges navigating young adulthood and tend to parent earlier than their peers may be at particularly increased risk of poor outcomes. To date, little research has been done to understand the experiences of young adult parents, especially those with SMHC. This study describes themes from qualitative interviews with 18 young adults with SMHC in the United States who became parents before the age of 25. Life story narrative interviews, conducted mostly by young adults with lived experience, asked participants to describe their parenting and mental health experiences and their school, training, and work experiences. Participants described the challenges of simultaneously parenting young children and managing a mental health condition, experiences of discrimination, and fear of future discrimination related to their mental health condition. However, parents also expressed that their children motivated them to maintain recovery and build a good life for their family. This is the first study to qualitatively explore the experiences of young adult parents with SMHC. While many of these findings align with prior qualitative research on mothers with mental illness, by exclusively focusing on individuals who become parents earlier than their peers and including father experiences, this research adds to our understanding of how individuals simultaneously navigate parenting and managing a serious mental health condition. These findings should inform larger-scale research studies on the experiences and outcomes of young adults with SMHC who become parents in their late teens or early twenties. A better understanding of their experiences should inform public mental health services that incorporate parenting as an important element of an individual's personal recovery model.

Community-based Argentine tango dance program is associated with increased activity participation among individuals with Parkinson's disease

OBJECTIVE

To determine the effects of a 12-month community-based tango dance program on activity participation among individuals with Parkinson's disease (PD).

DESIGN

Randomized controlled trial with assessment at baseline, 3, 6, and 12 months.

SETTING

Intervention was administered in the community; assessments were completed in a university laboratory.

PARTICIPANTS

Volunteers with PD (n=62) enrolled in the study and were randomized to a treatment group; 10 participants did not receive the allocated intervention, and therefore the final analyzed sample included 52 participants.

INTERVENTIONS

Participants were randomly assigned to the tango group, which involved 12 months of twice-weekly Argentine tango dance classes, or to the no intervention control group (n=26 per group).

MAIN OUTCOME MEASURE

Current, new, and retained participation in instrumental, leisure, and social activities, as measured by the Activity Card Sort (with the dance activity removed).

RESULTS

Total current participation in the tango group was higher at 3, 6, and 12 months compared with baseline (Ps≤.008), while the control group did not change (Ps≥.11). Total activity retention (since onset of PD) in the tango group increased from 77% to 90% (P=.006) over the course of the study, whereas the control group remained around 80% (P=.60). These patterns were similar in the separate activity domains. The tango group gained a significant number of new social activities (P=.003), but the control group did not (P=.71).

CONCLUSIONS

Individuals with PD who participated in a community-based Argentine tango class reported increased participation in complex daily activities, recovery of activities lost since the onset of PD, and engagement in new activities. Incorporating dance into the clinical management of PD may benefit participation and subsequently quality of life for this population.

The DNA sequence of the H-2kb gene: evidence for gene conversion as a mechanism for the generation of polymorphism in histocompatibilty antigens

We have determined the DNA sequence of the H-2Kb gene of the C57B1/10 mouse. Comparison of this sequence with that of the allelic H-2Kd shows surprisingly that the exons have accumulated more mutations than their introns. Moreover, many of these changes in the exons are clustered in short regions or hot spots. Additional comparison of these sequences with the H-2Ld and H-2Db sequences shows that, in several cases, the altered sequence generated at the hot spot is identical to the corresponding region of a non-allelic H-2 gene. The clustered changes are responsible for 60% of the amino acid differences between the H-2Kb and H-2Kd genes and suggest that micro-gene conversion events occurring within the exons and involving only tens of nucleotides are an important mechanism for the generation of polymorphic differences between natural H-2 alleles.

Use of menopausal estrogens and medroxyprogesterone in the United States, 1982-1992

OBJECTIVE

To describe trends in the prescription of menopausal estrogens and medroxyprogesterone in the United States.

METHODS

Annual estimates of the number of prescriptions for menopausal estrogens and medroxyprogesterone and descriptive information on patients and providers were obtained from two pharmaceutical marketing research data bases, the National Prescription Audit and the National Disease and Therapeutic Index of IMS America.

RESULTS

An estimated 13.6 million prescriptions were dispensed for oral menopausal estrogens in 1982, and 31.7 million in 1992, a 2.3-fold increase (P = .0001). In 1992, Premarin, the only oral conjugated estrogen currently approved for use, was the most frequently dispensed brand-name pharmaceutical in the United States. Dispensed prescriptions for Estraderm, a transdermal estradiol first marketed in 1986, increased from 1.5 million in 1987 to 4.7 million in 1992. Dispensed prescriptions for oral medroxyprogesterone also increased from 2.3 million prescriptions in 1982 to 11.3 million in 1992, a 4.9-fold increase (P = .0001). An estimated one in six to one in four postmenopausal women were taking menopausal hormones in 1992. These drugs were prescribed mainly by obstetrician-gynecologists.

CONCLUSION

The use of menopausal estrogens and medroxyprogesterone has increased substantially over the past decade. These trends indicate that American women are widely exposed to menopausal hormone replacement.

Cochleovestibular toxicity related to dichloromethotrexate

A 69-year-old man receiving monotherapy for lung cancer with dichloromethotrexate (DCM), and without exposure to other chemotherapeutic agents or known ototoxic drugs, developed profound cochleovestibular dysfunction. The initial presentation was vestibular. This resolved, but unilateral hearing loss ensued and continued to progress to a total of 80 db loss in the low frequency range and 40 db in the high range, despite discontinuation of the drug. Because DCM may be used in combination with the known ototoxin cisplatin, the potential of DCM as an ototoxin should also be considered in such patients.

Cyclic AMP, the hyperresponsiveness factor from hog kidney

The isolation and identification of a material present in the plasma of hypertensive dogs and hypertensive human patients has been under study since 1972. The earliest experiments in relation to this work, noted that plasma from hypertensive dogs cause a hyperresponse to norepinephrine when both were administered by way of the vein. Employing a rat assay system that consisted of an anesthetized rat with polyethylene catheters in the vein for giving norepinephrine and the test fractions and a catheter in the artery for blood pressure monitoring, fractions from hog kidney were tested for hyperresponsiveness activity. The active material is very comparable to cyclic AMP in molecular weight, ultraviolet spectrum, paper chromatography, Enzyme hydrolysis and activity in the anesthetized rat system. This evidence indicates that the hyperresponsiveness factor of renal origin is cyclic AMP.

Organization and evolution of the class I gene family in the major histocompatibility complex of the C57BL/10 mouse

The major histocompatibility complex (MHC) encodes several classes of protein vital to the regulation of the immune response. We have isolated 26 class I genes that map to this region in the C57BL/10 mouse and linked these into three gene clusters. The number of genes differs from the number found in the BALB/c strain and comparison of the organization of the class I genes in these two strains shows conserved regions and polymorphic regions which probably result from deletions, insertions and translocations within the MHC.

Effect of cimetidine on the pharmacokinetics and pharmacodynamics of quinidine

The influence of cimetidine (1.2 g/day for 7 days) on the disposition and pharmacodynamic effects of a single oral dose of quinidine was studied in 6 normal volunteers. Cimetidine reduced the mean apparent oral clearance of quinidine (+/- standard error of the mean) from 25.5 +/- 2.7 to 16.2 +/- 1.4 liters/h (p less than 0.05). This was reflected in a 55% (range 30 to 109) increase in the mean half-life from 5.8 +/- 0.2 to 9.0 +/- 0.6 hours (p less than 0.05). Peak quinidine plasma concentrations and times to peak were also increased (p less than 0.05). Plasma protein binding and urinary excretion of quinidine were unchanged by cimetidine treatment. Alterations in the pharmacokinetic variables of quinidine were mirrored in simultaneously measured electrocardiographic parameters. Changes in Q-T, rate-corrected Q-T, QRS, and R-R intervals after a single oral dose of quinidine sulfate (400 mg) were significant. Treatment with cimetidine potentiated these pharmacodynamic changes, but failed to achieve significant differences from quinidine alone. Thus, cimetidine impairs the elimination of oral quinidine in normal volunteers. This interaction may lead to quinidine toxicity in patients in whom cimetidine is concomitantly administered.

Expression of murine H-2Kb histocompatibility antigen in cells transformed with cloned H-2 genes

Cosmids containing H-2 histocompatibility antigen genes of the H-2b haplotype have been isolated. One of these genes expresses a 45,000 molecular weight protein, indistinguishable from H-2Kb when introduced into mouse L cells. These H-2Kb transformed L cells can be killed by allospecific anti-H-2Kb cytotoxic T cells. Moreover, when infected with influenza virus, they can be killed by an H-2Kb-restricted, influenza virus-specific cytotoxic T cell line. These results show that expression of the H-2Kb gene product on the L-cell surface is sufficient to make it a target for specific T-cell killing.

Superovulation-induced intrauterine growth retardation in mice

Existing animal models for inducing intrauterine growth retardation (IUGR) involve severe maternal compromise or acute fetal insult. We postulated that superovulation would produce IUGR gradually by enhancing fetal competition for nutrients. Mice were superovulated with pregnant mare serum and human chorionic gonadotrophin and killed on day 19 of gestation. Compared to controls, the mean number of fetuses was significantly increased; body, brain, liver, and placental weights were reduced; and brain/liver weight ratios were increased. Additional mice underwent partial unilateral oophorectomy before superovulation. Marked asymmetry in the number of fetuses in the two uterine horns of the same mother was produced, and the fetuses on the more crowded side manifested smaller brains and livers an increased brain/liver ratios. In the mouse, superovulation is a simple, preconceptual method for achieving IUGR and may be combined with partial unilateral oophorectomy to permit comparisons between fetuses with different growth characteristics within the same mother.

Accumulation of individual pA+ RNAs during oogenesis of Xenopus laevis

RNA metabolism during amphibian oogenesis has been investigated by the analysis of individual cDNA cloned sequences. Two cDNA clone libraries were constructed from the pA+ RNA of Xenopus ovary and of tadpole. The accumulation of RNAs complementary to individual clones was examined during oogenesis by isolating RNA from oocytes of different stages. There are only two patterns of accumulation during oogenesis. Mitochondrial mRNA sequences accumulate throughout all the stages of oogenesis, whereas all other sequences detected cease accumulation early in oogenesis and remain at a constant steady state level for the remainder of oocyte development. In the earliest stages examined, the individual RNAs are already present at approximately 1/4 their final level, and the subsequent increase of all sequences appears to be coordinant. These basic observations were confirmed by colony screening approximately 500 clones. The pattern of RNA accumulation observed is significant, because it had been determined that the total steady state pA+ RNA levels in the oocyte also ceased to increase at the same stage in oogenesis in which each individual sequenced reached a plateau level. In addition, lampbrush chromosomes, which have traditionally been thought to be the site of oocyte pA+ RNA synthesis, are maximally active after the stage in which all pA+ RNAs seem to have reached their final level of accumulation.