Cone-Beam Computed Tomography (CBCT)-Guided Adaptive Boost Radiotherapy for a Patient With Locally Advanced Cervical Cancer Ineligible for Brachytherapy.

Brachytherapy is a critical component of locally advanced cervical cancer treatment, and patients ineligible for brachytherapy historically have poor outcomes. Delivery of boost with stereotactic body radiation therapy (SBRT) has been studied, though toxicity is a concern. Recent case reports have explored adaptive radiation boost, which can adjust plans for inter-fraction motion using magnetic resonance guidance. Herein, we report the first patient with locally advanced cervical cancer ineligible for brachytherapy who was treated with a cone-beam computed tomography (CBCT)-guided adaptive boost following completion of chemoradiation. A 71-year-old female with locally advanced cervical cancer was treated with chemoradiation and was deemed ineligible for a brachytherapy boost due to tumor size, geometry, and a fistula with a tumor in the bladder. She was prescribed a boost to the primary tumor of 25 Gy in five fractions using CBCT-guided adaptive radiation following the completion of chemoradiation. A simulation was performed using a non-contrast CT fused with a mid-chemoradiation magnetic resonance imaging (MRI) scan to create an initial plan. For each treatment fraction, kilovoltage CBCTs were acquired, contours of organs at risk (OARs) were adjusted to reflect anatomy-of-the-day, and an adapted plan was generated. The initial and adapted plans were compared using dose-volume histogram objectives, and the adapted plan was used if it resolved OAR constraint violations or improved target coverage. The use of the initial treatment plan would have resulted in constraint violations for the rectum, sigmoid, and bladder in all fractions. The adapted plans achieved hard constraints in all fractions for all four critical OARs. The mean total treatment time across all five fractions was 58 minutes. This case demonstrates the feasibility of a CBCT-guided adaptive boost approach and the dosimetric benefits of plan adaptation in this setting. Though larger-scale and longer-term data are needed, CBCT-guided adaptive radiation may present a feasible alternative modality to deliver boost doses for brachytherapy-ineligible patients.

Dosimetric evaluation of a novel modular cell irradiation platform for multi-modality in vitro studies including high dose rate brachytherapy.

PURPOSE: High dose-rate (HDR) brachytherapy is integral for the treatment of numerous cancers. Preclinical studies involving HDR brachytherapy are limited. We aimed to describe a novel platform allowing multi-modality studies with clinical HDR brachytherapy and external beam irradiators, establish baseline dosimetry standard of a preclinical orthovoltage irradiator, to determine accurate dosimetric methods. METHODS: A dosimetric assessment of a commercial preclinical irradiator was performed establishing the baseline dosimetry goals for clinical irradiators. A 3D printed platform was then constructed with 14 brachytherapy channels at 1cm spacing to accommodate a standard tissue culture plate at a source-to-cell distance (SCD) of 1 cm or 0.4 cm. 4-Gy CT-based treatment plans were created in clinical treatment planning software and delivered to 96-well tissue culture plates using an Ir192 source or a clinical linear accelerator. Standard calculation models for HDR brachytherapy and external beam were compared to corresponding deterministic model-based dose calculation algorithms (MBDCAs). Agreement between predicted and measured dose was assessed with 2D-gamma passing rates to determine the best planning methodology. RESULTS: Mean (±standard deviation) and median dose measured across the plate for the preclinical irradiator was 423.7 ± 8.5 cGy and 430.0 cGy. Mean percentage differences between standard and MBDCA dose calculations were 9.4% (HDR, 1 cm SCD), 0.43% (HDR, 0.4 cm SCD), and 2.4% (EBRT). Predicted and measured dose agreement was highest for MBDCAs for all modalities. CONCLUSION: A 3D-printed tissue culture platform can be used for multi-modality irradiation studies with great accuracy. This tool will facilitate preclinical studies to reveal biologic differences between clinically relevant radiation modalities.

Accuracy of surveillance serum squamous cell carcinoma antigen for cervical cancer recurrence after definitive chemoradiation.

OBJECTIVE: Recurrence remains a significant clinical problem for patients with cervical cancer, and early detection may improve outcomes. Serum squamous cell carcinoma antigen (SCCA) is a biomarker of prognosis and response to chemoradiotherapy. We hypothesized that elevated serum SCCA during surveillance is sensitive and specific for recurrence. METHODS: Pre-treatment and follow-up serum SCCA from patients treated with definitive-intent radiotherapy were measured via enzyme-linked immunosorbent assay in a Clinical Laboratory Improvement Amendments (CLIA)-certified laboratory and analyzed retrospectively. Follow-up SCCA was defined as the value closest to recurrence, or as last available for patients without recurrence. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of follow-up SCCA for recurrence was determined for the whole cohort (Cohort 1), for patients with elevated (Cohort 2), and normal pre-treatment SCCA (Cohort 3). Patterns of failure were also evaluated. RESULTS: Of 227 patients in Cohort 1, 23% experienced recurrence, and 17% died of cervical cancer. Mean follow-up SCCA was 0.9 (±2.5) for patients with no recurrence and 6.0 (±18.7) for patients with recurrence (p=0.02). Sensitivity, specificity, PPV, and NPV of follow-up SCCA for recurrence in Cohort 1 were 38.5%, 97.1%, 80%, and 84.2%, and for patients in Cohort 2 were 54.5%, 95%, 78.3%, and 86.5%, respectively. Four of 86 patients in Cohort 3 had an elevated follow-up SCCA, two of these at the time of recurrence. Elevated pre-treatment SCCA and follow-up SCCA were associated with isolated pelvic recurrence. CONCLUSIONS: Surveillance serum SCCA has high specificity and NPV for recurrence, and may be of limited utility in patients with normal pre-treatment SCCA.

Sustained Response with Dose-reduced Selpercatinib in a Pediatric Patient with Metastatic NCOA4-RET Fusion Papillary Thyroid Carcinoma.

Understanding the molecular landscape of papillary thyroid carcinoma (PTC), the most common thyroid cancer in children, creates additional therapeutic approaches. RET gene rearrangements are observed in pediatric PTC, and selective inhibition of RET is now possible with specific tyrosine kinase inhibitors designed to target diverse RET -activating alterations. We present a 13-year-old female with metastatic PTC, clinically resistant to radioactive iodine, and found to harbor a NCOA4-RET fusion. She responded to selpercatinib treatment with the elimination of supplemental oxygen need, marked reduction in pulmonary nodules and mediastinal lymphadenopathy, and biomarker decline. The response was maintained despite 2 dose reductions for possibly related weight gain.

SCCA1/SERPINB3 suppresses antitumor immunity and blunts therapy-induced T cell responses via STAT-dependent chemokine production.

Patients with cancer who have high serum levels of squamous cell carcinoma antigen 1 (SCCA1, now referred to as SERPINB3) commonly experience treatment resistance and have a poor prognosis. Despite being a clinical biomarker, the modulation of SERPINB3 in tumor immunity is poorly understood. We found positive correlations of SERPINB3 with CXCL1, CXCL8 (CXCL8/9), S100A8, and S100A9 (S100A8/A9) myeloid cell infiltration through RNA-Seq analysis of human primary cervical tumors. Induction of SERPINB3 resulted in increased CXCL1/8 and S100A8/A9 expression, which promoted monocyte and myeloid-derived suppressor cell (MDSC) migration in vitro. In mouse models, Serpinb3a tumors showed increased MDSC and tumor-associated macrophage (TAM) infiltration, contributing to T cell inhibition, and this was further augmented upon radiation. Intratumoral knockdown (KD) of Serpinb3a resulted in tumor growth inhibition and reduced CXCL1 and S100A8/A expression and MDSC and M2 macrophage infiltration. These changes led to enhanced cytotoxic T cell function and sensitized tumors to radiotherapy (RT). We further revealed that SERPINB3 promoted STAT-dependent expression of chemokines, whereby inhibition of STAT activation by ruxolitinib or siRNA abrogated CXCL1/8 and S100A8/ A9 expression in SERPINB3 cells. Patients with elevated pretreatment SCCA levels and high phosphorylated STAT3 (p-STAT3) had increased intratumoral CD11b+ myeloid cells compared with patients with low SCCA levels and p-STAT3, who had improved overall survival after RT. These findings provide a preclinical rationale for targeting SERPINB3 in tumors to counteract immunosuppression and improve the response to RT.

SCCA1/SERPINB3 promotes suppressive immune environment via STAT-dependent chemokine production, blunting the therapy-induced T cell responses.

Radiotherapy is a commonly used cancer treatment; however, patients with high serum squamous cell carcinoma antigen (SCCA1/SERPINB3) are associated with resistance and poor prognosis. Despite being a strong clinical biomarker, the modulation of SERPINB3 in tumor immunity is poorly understood. We investigated the microenvironment of SERPINB3 high tumors through RNAseq of primary cervix tumors and found that SERPINB3 was positively correlated with CXCL1/8, S100A8/A9 and myeloid cell infiltration. Induction of SERPINB3 in vitro resulted in increased CXCL1/8 and S100A8/A9 production, and supernatants from SERPINB3-expressing cultures attracted monocytes and MDSCs. In murine tumors, the orthologue mSerpinB3a promoted MDSC, TAM, and M2 macrophage infiltration contributing to an immunosuppressive phenotype, which was further augmented upon radiation. Radiation-enhanced T cell response was muted in SERPINB3 tumors, whereas Treg expansion was observed. A STAT-dependent mechanism was implicated, whereby inhibiting STAT signaling with ruxolitinib abrogated suppressive chemokine production. Patients with elevated pre-treatment serum SCCA and high pSTAT3 had increased intratumoral CD11b+ myeloid cell compared to patients with low SCCA and pSTAT3 cohort that had overall improved cancer specific survival after radiotherapy. These findings provide a preclinical rationale for targeting STAT signaling in tumors with high SERPINB3 to counteract the immunosuppressive microenvironment and improve response to radiation.

Improving cervical cancer survival-A multifaceted strategy to sustain progress for this global problem.

Cervical cancer is associated with profound socioeconomic and racial disparities in incidence, mortality, morbidity, and years of life lost. The last standard-of-care treatment innovation for locally advanced cervical cancer occurred in 1999, when cisplatin chemotherapy was added to pelvic radiation therapy (chemoradiation therapy). Chemoradiation therapy is associated with a 30%-50% failure rate, and there is currently no cure for recurrent or metastatic disease. The enormity of the worldwide clinical problem of cervical cancer morbidity and mortality as well as the egregiously unchanged mortality rate over the last several decades are recognized by the National Institutes of Health as urgent priorities. This is reflected within the Office of Research on Women's Health effort to advance National Institutes of Health research on the health of women, as highlighted in a recent symposium. In the current review, the authors address the state of the science and opportunities to improve cervical cancer survival with an emphasis on improving access, using technology in innovative and widely implementable ways, and improving current understanding of cervical cancer biology. LAY SUMMARY: Cervical cancer is associated with profound socioeconomic and racial disparities in incidence, mortality, morbidity, and years of life lost. In this review, the state of the science and opportunities to improve cervical cancer survival are presented with an emphasis on improving access, using technology in innovative and widely implementable ways, and improving current understanding of cervical cancer biology.

Monounsaturated and Diunsaturated Fatty Acids Sensitize Cervical Cancer to Radiation Therapy.

Obesity induces numerous physiological changes that can impact cancer risk and patient response to therapy. Obese patients with cervical cancer have been reported to have superior outcomes following chemoradiotherapy, suggesting that free fatty acids (FFA) might enhance response to radiotherapy. Here, using preclinical models, we show that monounsaturated and diunsaturated FFAs (uFFA) radiosensitize cervical cancer through a novel p53-dependent mechanism. UFFAs signaled through PPARγ and p53 to promote lipid uptake, storage, and metabolism after radiotherapy. Stable isotope labeling confirmed that cervical cancer cells increase both catabolic and anabolic oleate metabolism in response to radiotherapy, with associated increases in dependence on mitochondrial fatty acid oxidation for survival. In vivo, supplementation with exogenous oleate suppressed tumor growth in xenografts after radiotherapy, an effect that could be partially mimicked in tumors from high fat diet-induced obese mice. These results suggest that supplementation with uFFAs may improve tumor responses to radiotherapy, particularly in p53 wild-type tumors. SIGNIFICANCE: Metabolism of monounsaturated and diunsaturated fatty acids improves the efficacy of radiotherapy in cancer through modulation of p53 activity. See related commentary by Jungles and Green, p. 4513.

Thyroid Carcinoma, Version 2.2022, NCCN Clinical Practice Guidelines in Oncology.

Differentiated thyroid carcinomas is associated with an excellent prognosis. The treatment of choice for differentiated thyroid carcinoma is surgery, followed by radioactive iodine ablation (iodine-131) in select patients and thyroxine therapy in most patients. Surgery is also the main treatment for medullary thyroid carcinoma, and kinase inhibitors may be appropriate for select patients with recurrent or persistent disease that is not resectable. Anaplastic thyroid carcinoma is almost uniformly lethal, and iodine-131 imaging and radioactive iodine cannot be used. When systemic therapy is indicated, targeted therapy options are preferred. This article describes NCCN recommendations regarding management of medullary thyroid carcinoma and anaplastic thyroid carcinoma, and surgical management of differentiated thyroid carcinoma (papillary, follicular, Hürthle cell carcinoma).

Overall survival in patients with FIGO stage IVA cervical cancer.

OBJECTIVE: FIGO stage IVA cervical cancer is a unique diagnosis that conveys a poor prognosis. Despite the use of PET/CT for staging, concurrent chemotherapy, and image-guided brachytherapy, overall survival (OS) in these patients is low. Treatment requires aggressive use of radiotherapy and chemotherapy. We report results of a prospective observational cohort study for patients with de novo stage IVA cervical cancer treated at a single institution. METHODS: Patients with a new diagnosis of stage IVA cervical cancer treated at an academic institution between 1997 and 2020 were prospectively monitored. Staging was retroactively assigned using the 2018 FIGO staging system. All patients had a PET/CT prior to treatment and were treated with definitive intent radiotherapy with or without chemotherapy. The primary outcome of interest was OS. Secondary outcomes were local control, progression-free survival (PFS), and disease-specific survival (DSS). RESULTS: 32 patients with de novo stage IVA cervical cancer were treated with definitive intent radiotherapy. Median follow-up time was 4.27 years (1.31-10.35). 22/32 (69%) of patients received brachytherapy as a part of their definitive treatment, and 28/32 (88%) received chemotherapy concurrently with radiotherapy. 14/32 (44%) of patients had no evidence of disease at last follow-up. The 5-year local control, PFS, DFS, and OS estimates were 79%, 49%, 53%, and 48%, respectively. On multivariate analysis, complete metabolic response was associated with a statistically significant improvement in PFS (HR = 0.256, 95% CI = 0.078-0.836, p = 0.024) and OS (HR = 0.273, 95% CI 0.081-0.919). CONCLUSIONS: These data demonstrate a robust OS in patients with stage IVA cervical cancer when treated with definitive chemoradiotherapy.

The impact of tumor size and histology on local control when utilizing high-dose-rate interstitial brachytherapy for gynecologic malignancies.

OBJECTIVE: To report long-term results of an outpatient template-based high-dose-rate interstitial brachytherapy (HDR ISBT) program for the treatment of gynecologic malignancies. METHODS: Patients treated between 2006 and 2020 at an academic hospital with outpatient template based HDR ISBT without spinal or general anesthesia were reviewed. Patients who had previously received HDR ISBT were excluded. Baseline patient, tumor, and treatment characteristics, such as tumor size, histology, and/or total EQD2 including prior external beam radiation therapy (EBRT) were recorded. Local control and overall survival were estimated using the Kaplan-Meier method, and factors associated with local control and overall survival were evaluated using Cox regression analyses. RESULTS: 150 patients received HDR ISBT for a gynecologic tumor and the median follow-up time was 2.98 years (0.89-4.82). Of those, 74/150 (49%) were treated definitively, 69/150 (46%) were treated for tumor recurrence/persistence, and 7/150 (5%) were treated for durable palliation. Median tumor size was 3.00 cm (1.50-4.00). 124/150 (83%) patients received EBRT prior to HDR ISBT. Median HDR ISBT dose was 18 Gy delivered in eight fractions. Local control was 71% (64%-79%), 58% (50%-68%), and 57% (48%-67%) at one, three, and five years, respectively. On multivariate analysis, non-endometrial adenocarcinoma histology (HR = 2.423, 95% CI = 1.011-5.808, p = 0.047) and tumor size ≥ 3 cm (HR = 2.903, 95% CI 1.053-3.441, p = 0.033) were associated with lower local control. CONCLUSIONS: The majority of patients who received outpatient-based twice daily HDR ISBT had long-term local control. Larger tumor size and non-endometrial adenocarcinoma histology were detrimental to local control.

Expression of Potential Biomarker Targets by Immunohistochemistry in Cervical Carcinomas.

There have been few clinically useful targetable biomarkers in uterine cervical carcinomas. Estrogen receptor (ER), HER2, and fibroblast activation protein (FAP) are potential therapeutic or theranostic targets in other gynecologic and genitourinary carcinoma types. We determined the immunohistochemical expression patterns of these markers in treatment-naive cervical carcinoma, and whether expression correlated with clinical outcomes after definitive chemoradiation therapy. Tissue microarrays were created from 71 patient samples taken before therapy (57 squamous cell carcinomas and 14 nonsquamous cell carcinomas) and stained for ER, HER2, and FAP. ER was positive in 25/70 cases (36%). Of 66 tumors with evaluable HER2 staining, only 1 had positive (3+) staining (3%, positive for HER2 amplification by fluorescence in situ hybridization), and 1 had equivocal (2+) staining (negative for amplification by fluorescence in situ hybridization). The remainder were negative for HER2 overexpression. FAP expression was widely variably in the tumor stroma. ER positivity and FAP expression did not correlate with cervical recurrence, pelvic recurrence, distant recurrence, or cancer death. In conclusion, HER2 amplification is very rare in nonmetastatic treatment-naive cervical carcinomas, but if present, could represent a target for antibody therapy. ER and FAP were expressed in a subset of tumors, but expression did not correlate with clinical outcomes. These immunohistochemical markers do not demonstrate prognostic significance in treatment-naive cervical cancer, but they may have utility in targeted therapy or imaging.

Lysoptosis is an evolutionarily conserved cell death pathway moderated by intracellular serpins.

Lysosomal membrane permeabilization (LMP) and cathepsin release typifies lysosome-dependent cell death (LDCD). However, LMP occurs in most regulated cell death programs suggesting LDCD is not an independent cell death pathway, but is conscripted to facilitate the final cellular demise by other cell death routines. Previously, we demonstrated that Caenorhabditis elegans (C. elegans) null for a cysteine protease inhibitor, srp-6, undergo a specific LDCD pathway characterized by LMP and cathepsin-dependent cytoplasmic proteolysis. We designated this cell death routine, lysoptosis, to distinguish it from other pathways employing LMP. In this study, mouse and human epithelial cells lacking srp-6 homologues, mSerpinb3a and SERPINB3, respectively, demonstrated a lysoptosis phenotype distinct from other cell death pathways. Like in C. elegans, this pathway depended on LMP and released cathepsins, predominantly cathepsin L. These studies suggested that lysoptosis is an evolutionarily-conserved eukaryotic LDCD that predominates in the absence of neutralizing endogenous inhibitors.

SERPINB3 (SCCA1) inhibits cathepsin L and lysoptosis, protecting cervical cancer cells from chemoradiation.

The endogenous lysosomal cysteine protease inhibitor SERPINB3 (squamous cell carcinoma antigen 1, SCCA1) is elevated in patients with cervical cancer and other malignancies. High serum SERPINB3 is prognostic for recurrence and death following chemoradiation therapy. Cervical cancer cells genetically lacking SERPINB3 are more sensitive to ionizing radiation (IR), suggesting this protease inhibitor plays a role in therapeutic response. Here we demonstrate that SERPINB3-deficient cells have enhanced sensitivity to IR-induced cell death. Knock out of SERPINB3 sensitizes cells to a greater extent than cisplatin, the current standard of care. IR in SERPINB3 deficient cervical carcinoma cells induces predominantly necrotic cell death, with biochemical and cellular features of lysoptosis. Rescue with wild-type SERPINB3 or a reactive site loop mutant indicates that protease inhibitory activity is required to protect cervical tumor cells from radiation-induced death. Transcriptomics analysis of primary cervix tumor samples and genetic knock out demonstrates a role for the lysosomal protease cathepsin L in radiation-induced cell death in SERPINB3 knock-out cells. These data support targeting of SERPINB3 and lysoptosis to treat radioresistant cervical cancers.

Phase I Trial of Stereotactic MRI-Guided Online Adaptive Radiation Therapy (SMART) for the Treatment of Oligometastatic Ovarian Cancer.

PURPOSE: Stereotactic body radiation therapy is increasingly used to treat a variety of oligometastatic histologies, but few data exist for ovarian cancer. Ablative stereotactic body radiation therapy dosing is challenging in sites like the abdomen, pelvis, and central thorax due to proximity and motion of organs at risk. A novel radiation delivery method, stereotactic magnetic-resonance-guided online-adaptive radiation therapy (SMART), may improve the therapeutic index of stereotactic body radiation therapy through enhanced soft-tissue visualization, real-time nonionizing imaging, and ability to adapt to the anatomy-of-the-day, with the goal of producing systemic-therapy-free intervals. This phase I trial assessed feasibility, safety, and dosimetric advantage of SMART to treat ovarian oligometastases. METHODS AND MATERIALS: Ten patients with recurrent oligometastatic ovarian cancer underwent SMART for oligometastasis ablation. Initial plans prescribed 35 Gy/5 fractions with goal 95% planning target volume coverage by 95% of prescription, with dose escalation permitted, subject to strict organ-at-risk dose constraints. Daily adaptive planning was used to protect organs-at-risk and/or increase target dose. Feasibility (successful delivery of >80% of fractions in the first on-table attempt) and safety of this approach was evaluated, in addition to efficacy, survival metrics, quality-of-life, prospective timing and dosimetric outcomes. RESULTS: Ten women with seventeen ovarian oligometastases were treated with SMART, and 100% of treatment fractions were successfully delivered. Online adaptive plans were selected at time of treatment for 58% of fractions, due to initial plan violation of organs-at-risk constraints (84% of adapted fractions) or observed opportunity for planning target volume dose escalation (16% of adapted fractions), with a median on-table time of 64 minutes. A single Grade ≥3 acute (within 6 months of SMART) treatment-related toxicity (duodenal ulcer) was observed. Local control at 3 months was 94%; median progression-free survival was 10.9 months. Median Kaplan-Meier estimated systemic-therapy-free survival after radiation completion was 11.5 months, with concomitant quality-of-life improvements. CONCLUSIONS: SMART is feasible and safe for high-dose radiation therapy ablation of ovarian oligometastases of the abdomen, pelvis, and central thorax with minimal toxicity, high rates of local control, and prolonged systemic-therapy-free survival translating into improved quality-of-life.

Genomic Characterization and Therapeutic Targeting of HPV Undetected Cervical Carcinomas.

Cervical cancer tumors with undetectable HPV (HPVU) have been underappreciated in clinical decision making. In this study, two independent CC datasets were used to characterize the largest cohort of HPVU tumors to date (HPVU = 35, HPV+ = 430). Genomic and transcriptome tumor profiles and patient survival outcomes were compared between HPV+ and HPVU tumors. In vitro analyses were done to determine efficacy of the selective CDK4/6 inhibitor palbociclib on HPVU cancer cell lines. Patients with HPVU CC tumors had worse progression-free and overall survival outcomes compared to HPV+ patients. TP53, ARID1A, PTEN, ARID5B, CTNNB1, CTCF, and CCND1 were identified as significantly mutated genes (SMGs) enriched in HPVU tumors, with converging functional roles in cell cycle progression. In vitro HPVU, but not HPV+, cancer cell lines with wild type RB1 were sensitive to palbociclib monotherapy. These results indicate that HPVU status can be translated into the clinic as a predictive biomarker of poor patient response to standard of care treatments. We suggest primary cervix tumors be routinely tested for HPV prior to treatment to identify patients who will benefit from more aggressive precision-driven therapy. Our results identify palbociclib as a lead candidate as an alternative treatment strategy for HPVU CC patients.

HPV transcript expression affects cervical cancer response to chemoradiation.

Persistent HPV infection is causative for the majority of cervical cancer cases; however, current guidelines do not require HPV testing for newly diagnosed cervical cancer. Using an institutional cohort of 88 patients with cervical cancer treated uniformly with standard-of-care chemoradiation treatment (CRT) with prospectively collected clinical outcome data, we observed that patients with cervical tumors containing HPV genotypes other than HPV 16 have worse survival outcomes after CRT compared with patients with HPV 16+ tumors, consistent with previously published studies. Using RNA sequencing analysis, we quantified viral transcription efficiency and found higher levels of E6 and the alternative transcript E6*I in cervical tumors with HPV genotypes other than HPV 16. These findings were validated using whole transcriptome data from The Cancer Genome Atlas (n = 304). For the first time to our knowledge, transcript expression level of HPV E6*I was identified as a predictive biomarker of CRT outcome in our complete institutional data set (n = 88) and within the HPV 16+ subset (n = 36). In vitro characterization of HPV E6*I and E6 overexpression revealed that both induce CRT resistance through distinct mechanisms dependent upon p53-p21. Our findings suggest that high expression of E6*I and E6 may represent novel biomarkers of CRT efficacy, and these patients may benefit from alternative treatment strategies.

Standardized Uptake Value for 18F-Fluorodeoxyglucose Is a Marker of Inflammatory State and Immune Infiltrate in Cervical Cancer.

PURPOSE: Chemoradiotherapy for locally advanced cervical cancer fails in over a third of patients. Biomarkers with therapeutic implications are therefore needed. We investigated the relationship between an established prognostic marker, maximum standardized uptake value (SUVmax) on 18F-fluorodeoxyglucose positron emission tomography, and the inflammatory and immune state of cervical cancers. EXPERIMENTAL DESIGN: An SUVmax most prognostic for freedom from progression (FFP) was identified and compared with known prognostic clinical variables in a cohort of 318 patients treated with definitive radiation with prospectively collected clinical data. Gene set enrichment analysis (GSEA) and CIBERSORT of whole-transcriptome data from 68 patients were used to identify biological pathways and immune cell subpopulations associated with high SUVmax. IHC using a tissue microarray (TMA, N = 82) was used to validate the CIBERSORT findings. The impact of macrophages on cervical cancer glucose metabolism was investigated in coculture experiments. RESULTS: SUVmax <11.4 was most prognostic for FFP (P = 0.001). The GSEA showed that high SUVmax is associated with increased gene expression of inflammatory pathways, including JAK/STAT3 signaling. CIBERSORT and CD68 staining of the TMA showed high SUVmax tumors are characterized by a monocyte-predominant immune infiltrate. Coculture of cervical cancer cells with macrophages or macrophage-conditioned media altered glucose uptake, and IL6 and JAK/STAT3 signaling contribute to this effect. CONCLUSIONS: SUVmax is a prognostic marker in cervical cancer that is associated with activation of inflammatory pathways and tumor infiltration of myeloid-derived immune cells, particularly macrophages. Macrophages contribute to changes in cervical cancer glucose metabolism.See related commentary by Williamson et al., p. 4136.