Final outcomes analysis of the cell product SQZ-PBMC-HPV Phase 1 trial in incurable HPV16+ solid tumors shows improved overall survival in patients with increased CD8+ T cell tumor infiltration.

Cancer vaccines strive to induce robust, antigen-targeted, T-cell-mediated immune responses but have struggled to produce meaningful regression in solid tumors. An autologous cell vaccine, SQZ-PBMC-HPV, was developed by SQZ Biotechnologies using microfluidic squeezing technology to load PBMCs with HPV16 E6 and E7 antigens in HLA-A*02+ patients. The SQZ-PBMC-HPV-101 Phase 1 trial (NCT04084951) enrolled patients with incurable HPV16+ cancers. Here, we present a post hoc analysis of the relationship between Posttreatment CD8+ T cell infiltration and patient outcomes. SQZ-PBMC-HPV was administered as monotherapy every 3 weeks. Tumor samples were collected pre-dose and post-dose 4 weeks after treatment start. Biomarkers including CD8, MHC-I, E6, E7, GZMB, and Ki67 were evaluated by immunohistochemistry, immunofluorescence, and RNA in situ hybridization, and were correlated with clinical response, survival, and drug product composition. Eighteen patients had paired pre- and post-dose biopsies. Six (33%) had an increase in CD8+ T cell density in tumor parenchyma between screening and C2D8. Patients with increased CD8+ T cell density had improved disease control rate (66.7% vs 16.7%) and median overall survival (606.5 days vs 170.0 days, p = 0.0078). Drug product was significantly enriched for higher T cells and lower monocytes in the increased CD8+ T cell density group. In patients with incurable HPV16+ solid tumors treated with SQZ-PBMC-HPV, an increase in CD8+ T cell density within the tumor parenchyma was associated with superior disease control rate and overall survival. The product composition for patients with increased CD8+ T cell density was enriched for T cells.

A molecular guide to systemic therapy in salivary gland carcinoma.

Salivary gland carcinomas (SGC) are a rare and variable group of head and neck cancers with historically poor response to cytotoxic chemotherapy and immunotherapy in the recurrent, advanced, and metastatic settings. In the last decade, a number of targetable molecular alterations have been identified in SGCs including HER2 upregulation, androgen receptor overexpression, Notch receptor activation, NTRK gene fusions, and RET alterations which have dramatically improved treatment outcomes in this disease. Here, we review the landscape of precision therapy in SGC including current options for systemic management, ongoing clinical trials, and promising future directions.

A continuing clinical education course to maintain clinical competencies and foster new clinical knowledge during the graduate school years of MD-PhD training.

Introduction: Most students in MD-PhD programs take a leave of absence from medical school to complete PhD training, which promotes a natural loss of clinical skills and knowledge and could negatively impact a student's long-term clinical knowledge. To address this concern, clinical refresher courses in the final year of PhD training have traditionally been used; however, effectiveness of such courses versus a longitudinal clinical course spanning all PhD training years is unclear. Methods: The University of Alabama at Birmingham MD-PhD Program implemented a comprehensive continuing clinical education (CCE) course spanning PhD training years that features three course components: (1) clinical skills; (2) clinical knowledge; and (3) specialty exposure activities. To evaluate course effectiveness, data from an anonymous student survey completed at the end of each semester were analyzed. Results: Five hundred and ninety-seven surveys were completed by MD-PhD students from fall 2014 to 2022. Survey responses indicated that the majority of students found the course helpful to: maintain clinical skills and knowledge (544/597, 91% and 559/597, 94%; respectively), gain exposure to clinical specialties (568/597, 95%), and prepare them for responsibilities during clinical clerkships. During semesters following lockdowns from the COVID-19 pandemic, there were significant drops in students' perceived preparedness. Conclusions: Positive student survey feedback and improved preparedness to return to clinic after development of the course suggests the CCE course is a useful approach to maintain clinical knowledge during research training.

Fostering a diverse regional community of physician-scientist trainees.

Among the many academic challenges faced by dual-degree MD-PhD students is access to professional support networks designed to overcome the unique academic and personal barriers to physician-scientist training. In the current study, we hypothesized that regional access to a student MD-PhD conference, termed the Southeastern Medical Scientist Symposium (SEMSS), would enhance medical and/or graduate training by fostering such relationships between physician-scientist trainees, doing so by discussing both the challenges of physician-scientist training and effective strategies to overcome them. In the current study, we used a mixed-methods approach to evaluate the overall usefulness of SEMSS over a ten-year period (2010-2020) to identify key areas of particular benefit to trainees. The authors used conference registration data to compile self-reported demographic and regional attendance, followed by a post-conference survey to gauge attendee satisfaction. Over the reporting period, SEMSS was attended by equivalent proportions of MD-PhD and undergraduate students, among which were a high-percentage of students from underrepresented minority (URM) groups relative to the national MD-PhD applicant pool; nearly one-third of URM students attendees later matriculated into MD-PhD programs, far exceeding the national MD-PhD matriculation rate. Among the benefits reported by students were "opportunities to network with peers" and opportunities to learn about the physician-scientist career track. Therefore, we therefore propose regional MD-PhD conferences as an effective model to promote diversity within the physician-scientist training pipeline.

Is It Safe to Ask the Questions That Matter Most to Me? Observations From a Female Residency Applicant.

Tens of thousands of senior medical students interview for medical residency positions each year. As the applicant pool shifts to include more women, married individuals, and young parents, the criteria by which interviewees evaluate programs are also changing. Concerns including parental leave policies, lactation facilities, access to childcare, partner recruitment resources, and inclusivity in the work environment are important in selecting an ideal program. However, the National Resident Matching Program Match Communication Code of Conduct prohibits interviewers from addressing gender, marital status, and intent to bear children, so the burden of introducing such topics falls on the interviewees. These topics can be difficult to discuss with potential employers, especially when weighed against the pressure to obtain a competitive position through the Match.In this Invited Commentary, the authors draw on personal experience to examine the questions that residency programs need to answer, encouraging both applicants and programs to improve communication during the residency interview process.

Gamification: An Innovative Approach to Reinforce Clinical Knowledge for MD-PhD Students During Their PhD Research Years.

A longstanding challenge facing MD-PhD students and other dual-degree medical trainees is the loss of clinical knowledge that occurs during the non medical phases of training. Academic medical institutions nationwide have developed continued clinical training and exposure to maintain clinical competence; however, quantitative assessment of their usefulness remains largely unexplored. The current study therefore sought to both implement and optimize an online game platform to support MD-PhD students throughout their research training. Sixty three current MD-PhD students completing the PhD research phase of training were enrolled in an institutionally-developed online game platform for 2 preliminary and 4 competition rounds of 3-4 weeks each. During preliminary game rounds, we found that participation, though initially high, declined precipitously throughout the duration of each round, with 37 students participating to some extent. Daily reminders were implemented in subsequent rounds, which markedly improved player participation. Average participation in competition rounds exceeded 35% (23/63) active participants each round, with trending improvement in scores throughout the duration of PhD training. Both player participation and progress through the research phase of the MD-PhD program correlated positively with game performance and therefore knowledge retention and/or acquisition. Coupled with positive survey-based feedback from participants, our data therefore suggest that gamification is an effective tool for MD-PhD programs to combat loss of clinical knowledge during research training.

Impact of elective versus required medical school research experiences on career outcomes.

Many US medical schools have added a scholarly or research requirement as a potential intervention to increase the number of medical students choosing to become academic physicians and physician scientists. We designed a retrospective qualitative survey study to evaluate the impact of medical school research at the University of Alabama at Birmingham (UAB) on career choices. A survey tool was developed consisting of 74 possible questions with built-in skip patterns to customize the survey to each participant. The survey was administered using the web-based program Qualtrics to UAB School of Medicine alumni graduating between 2000 and 2014. Alumni were contacted 3 times at 2-week intervals during the year 2015, resulting in 168 completed surveys (11.5% response rate). MD/PhD graduates were excluded from the study. Most respondents completed elective research, typically for reasons relating to career advancement. 24 per cent said medical school research increased their desire for research involvement in the future, a response that positively correlated with mentorship level and publication success. Although completion of medical school research was positively correlated with current research involvement, the strongest predictor for a physician scientist career was pre-existing passion for research (p=0.008). In contrast, students motivated primarily by curricular requirement were less likely to pursue additional research opportunities. Positive medical school research experiences were associated with increased postgraduate research in our study. However, we also identified a strong relationship between current research activity and passion for research, which may predate medical school.

DNA-PkCS expression in oropharyngeal squamous cell carcinoma: Correlations with human papillomavirus status and recurrence after transoral robotic surgery.

BACKGROUND: Human papillomavirus (HPV)-positive oropharyngeal squamous cell carcinoma (SCC) has improved clinical outcomes compared to HPV-negative disease. However, the biology underlying differences in prognosis remains unclear. METHODS: We characterized the expression of DNA-protein kinase catalytic subunit (DNA-PkCS ), a key DNA repair protein also associated with tumor progression, in 29 cases of oropharyngeal SCCs and correlated our findings with HPV status and disease recurrence. In addition, we assessed therapeutic response, migration, and invasion in head and neck cancer cell lines upon DNA-PkCS knockdown. RESULTS: DNA-PkCS expression was significantly decreased in HPV-positive compared to HPV-negative oropharyngeal SCC samples. Within the HPV-positive subgroup, DNA-PkCS expression was inversely related to HPV E6 and E7 expression and trended toward significance as a predictor of recurrence. DNA-PkCS knockdown in cell lines resulted in increased sensitivity to cisplatin and radiotherapy and reduced cell migration and invasion. CONCLUSION: These results suggest DNA-PkCS should be further studied as a potential marker of tumor progression in HPV-positive oropharyngeal SCCs. © 2016 Wiley Periodicals, Inc. Head Neck 39: 206-214, 2017.

Combining Chk1/2 Inhibition with Cetuximab and Radiation Enhances In Vitro and In Vivo Cytotoxicity in Head and Neck Squamous Cell Carcinoma.

EGFR inhibition and radiotherapy are potent inducers of DNA damage. Checkpoint kinases 1 and 2 (Chk1/2) are critical regulators of the DNA-damage response, controlling cell-cycle checkpoints that may permit recovery from therapy-associated genomic stress. We hypothesized that Chk1/2 inhibition (CHKi) with prexasertib may enhance cytotoxicity from EGFR inhibition plus radiotherapy in head and neck squamous cell carcinoma (HNSCC). In this study, we found that the addition of CHKi to the EGFR inhibitor cetuximab with and without radiotherapy significantly decreased cell proliferation and survival fraction in human papillomavirus virus (HPV)-positive and HPV-negative HNSCC cell lines. Reduced proliferation was accompanied by decreased checkpoint activation, induced S-phase accumulation, persistent DNA damage, and increased caspase cleavage and apoptosis. Importantly, a significant tumor growth delay was observed in vivo in both HPV-positive and HPV-negative cell line xenografts receiving triple combination therapy with CHKi, cetuximab, and radiotherapy without a concomitant increase in toxicity as assessed by mouse body weight. Taken together, the combination of CHKi with cetuximab plus irradiation displayed significant antitumor effects in HNSCCs both in vitro and in vivo, suggesting that this combination therapy may increase clinical benefit. A clinical trial to test this treatment for patients with head and neck cancer is currently ongoing (NCT02555644). Mol Cancer Ther; 16(4); 591-600. ©2017 AACR.

MARCKS phosphorylation is modulated by a peptide mimetic of MARCKS effector domain leading to increased radiation sensitivity in lung cancer cell lines.

Lung cancer is the leading cause of cancer-associated mortality in the United States. Kinase hyperactivation is a known mechanism of tumorigenesis. The phosphorylation status of the plasma membrane-associated protein myristoylated alanine rich C-kinase substrate (MARCKS) effector domain (ED) was previously established as being important in the sensitivity of lung cancer to radiation. Specifically, when MARCKS ED was in a non-phosphorylated state, lung cancer cells were more susceptible to ionizing radiation and experienced prolonged double-strand DNA breaks. Additional studies demonstrated that the phosphorylation status of MARCKS ED is important for gene expression and in vivo tumor growth. The present study used a peptide mimetic of MARCKS ED as a therapeutic intervention to modulate MARCKS phosphorylation. Culturing A549, H1792 and H1975 lung cancer cell lines with the MARCKS ED peptide led to reduced levels of phosphorylated MARCKS and phosphorylated Akt serine/threonine kinase 1. Further investigation demonstrated that the peptide therapy was able to reduce lung cancer cell proliferation and increase radiation sensitivity. In addition, the MARCKS peptide therapy was able to prolong double-strand DNA breaks following ionizing radiation exposure. The results of the present study demonstrate that a peptide mimetic of MARCKS ED is able to modulate MARCKS phosphorylation, leading to an increase in sensitivity to radiation.

Notch Signaling Activation Is Associated with Patient Mortality and Increased FGF1-Mediated Invasion in Squamous Cell Carcinoma of the Oral Cavity.

UNLABELLED: Oral squamous cell carcinoma (OSCC) is a cancer subtype that lacks validated prognostic and therapeutic biomarkers, and human papillomavirus status has not proven beneficial in predicting patient outcomes. A gene expression pathway analysis was conducted using OSCC patient specimens to identify molecular targets that may improve management of this disease. RNA was isolated from 19 OSCCs treated surgically at the University of Alabama at Birmingham (UAB; Birmingham, AL) and evaluated using the NanoString nCounter system. Results were confirmed using the oral cavity subdivision of the Head and Neck Squamous Cell Carcinoma Cancer (HNSCC) study generated by The Cancer Genome Atlas (TCGA) Research Network. Further characterization of the in vitro phenotype produced by Notch pathway activation in HNSCC cell lines included gene expression, proliferation, cell cycle, migration, invasion, and radiosensitivity. In both UAB and TCGA samples, Notch pathway upregulation was significantly correlated with patient mortality status and with expression of the proinvasive gene FGF1 In vitro Notch activation in HNSCC cells increased transcription of FGF1 and induced a marked increase in cell migration and invasion, which was fully abrogated by FGF1 knockdown. These results reveal that increased Notch pathway signaling plays a role in cancer progression and patient outcomes in OSCC. Accordingly, the Notch-FGF interaction should be further studied as a prognostic biomarker and potential therapeutic target for OSCC. IMPLICATIONS: Patients with squamous cell carcinoma of the oral cavity who succumb to their disease are more likely to have upregulated Notch signaling, which may mediate a more invasive phenotype through increased FGF1 transcription. Mol Cancer Res; 14(9); 883-91. ©2016 AACR.

DNA double strand break repair defect and sensitivity to poly ADP-ribose polymerase (PARP) inhibition in human papillomavirus 16-positive head and neck squamous cell carcinoma.

Patients with human papillomavirus-positive (HPV+) head and neck squamous cell carcinomas (HNSCCs) have increased response to radio- and chemotherapy and improved overall survival, possibly due to an impaired DNA damage response. Here, we investigated the correlation between HPV status and repair of DNA damage in HNSCC cell lines. We also assessed in vitro and in vivo sensitivity to the PARP inhibitor veliparib (ABT-888) in HNSCC cell lines and an HPV+ patient xenograft. Repair of DNA double strand breaks (DSBs) was significantly delayed in HPV+ compared to HPV- HNSCCs, resulting in persistence of γH2AX foci. Although DNA repair activators 53BP1 and BRCA1 were functional in all HNSCCs, HPV+ cells showed downstream defects in both non-homologous end joining and homologous recombination repair. Specifically, HPV+ cells were deficient in protein recruitment and protein expression of DNA-Pk and BRCA2, key factors for non-homologous end joining and homologous recombination respectively. Importantly, the apparent DNA repair defect in HPV+ HNSCCs was associated with increased sensitivity to the PARP inhibitor veliparib, resulting in decreased cell survival in vitro and a 10-14 day tumor growth delay in vivo. These results support the testing of PARP inhibition in combination with DNA damaging agents as a novel therapeutic strategy for HPV+ HNSCC.

Targeting the effector domain of the myristoylated alanine rich C-kinase substrate enhances lung cancer radiation sensitivity.

Lung cancer is the leading cause of cancer related deaths. Common molecular drivers of lung cancer are mutations in receptor tyrosine kinases (RTKs) leading to activation of the phosphatidylinositol 3-kinase (PI3K)/Akt pro-growth, pro-survival signaling pathways. Myristoylated alanine rich C-kinase substrate (MARCKS) is a protein that has the ability to mitigate this signaling cascade by sequestering the target of PI3K, phosphatidylinositol (4,5)-bisphosphate (PIP2). As such, MARCKS has been implicated as a tumor suppressor, though there is some evidence that MARCKS may be tumor promoting in certain cancer types. Since the MARCKS function depends on its phosphorylation status, which impacts its subcellular location, MARCKS role in cancer may depend highly on the signaling context. Currently, the importance of MARCKS in lung cancer biology is limited. Thus, we investigated MARCKS in both clinical specimens and cell culture models. Immunohistochemistry scoring of MARCKS protein expression in a diverse lung tumor tissue array revealed that the majority of squamous cell carcinomas stained positive for MARCKS while other histologies, such as adenocarcinomas, had lower levels. To study the importance of MARCKS in lung cancer biology, we used inducible overexpression of wild-type (WT) and non-phosphorylatable (NP)-MARCKS in A549 lung cancer cells that had a low level of endogenous MARCKS. We found that NP-MARCKS expression, but not WT-MARCKS, enhanced the radiosensitivity of A549 cells in part by inhibiting DNA repair as evidenced by prolonged radiation-induced DNA double strand breaks. We confirmed the importance of MARCKS phosphorylation status by treating several lung cancer cell lines with a peptide mimetic of the phosphorylation domain, the effector domain (ED), which effectively attenuated cell growth as measured by cell index. Thus, the MARCKS ED appears to be an important target for lung cancer therapeutic development.

Beyond DNA Repair: Additional Functions of PARP-1 in Cancer.

Poly(ADP-ribose) polymerases (PARPs) are DNA-dependent nuclear enzymes that transfer negatively charged ADP-ribose moieties from cellular nicotinamide-adenine-dinucleotide (NAD(+)) to a variety of protein substrates, altering protein-protein and protein-DNA interactions. The most studied of these enzymes is poly(ADP-ribose) polymerase-1 (PARP-1), which is an excellent therapeutic target in cancer due to its pivotal role in the DNA damage response. Clinical studies have shown susceptibility to PARP inhibitors in DNA repair defective cancers with only mild adverse side effects. Interestingly, additional studies are emerging which demonstrate a role for this therapy in DNA repair proficient tumors through a variety of mechanisms. In this review, we will discuss additional functions of PARP-1 - including regulation of inflammatory mediators, cellular energetics and death pathways, gene transcription, sex hormone- and ERK-mediated signaling, and mitosis - and the role these PARP-1-mediated processes play in oncogenesis, cancer progression, and the development of therapeutic resistance. As PARP-1 can act in both a pro- and anti-tumor manner depending on the context, it is important to consider the global effects of this protein in determining when, and how, to best use PARP inhibitors in anticancer therapy.