Analysis Of P53 Mutations Research Articles

Evaluation of P53 immunostaining in patients with cutaneous melanoma.

P53 is a tumor suppressor gene that is mutated in numerous types of cancer. The aim of the present study was to determine the frequency of this mutation in cutaneous melanomas and to conduct clinicopathological characteristics and clinical outcome association analyses with the P53 mutation. P53 immunohistochemical staining was used as a surrogate marker for P53 mutation analysis to assess P53 status. In the present study, 50 pathological samples of cutaneous melanoma from 2012 to 2018 at Chulalongkorn University (Bangkok, Thailand), were subjected to anti-P53 immunohistochemistry, followed by an examination of the association between P53 statuses and clinical and pathological characteristics, along with clinical outcomes. A positive staining for anti-P53 antibody was detected in 30% of patients (15/50) with cutaneous melanomas. Positivity was significantly associated with female sex, nodular histological subtype and Breslow level 4. Cox regression analysis revealed that an age >65.5 years and Breslow grade 4 disease were associated with mortality. The Kaplan-Meier curve revealed a shorter duration of recurrence time in the P53 mutation than P53 wild type. In the present study, P53 mutations in specific cases of cutaneous melanoma were identified. Notably, patients who were older and/or had a Breslow score of 4 exhibited an increased risk of mortality. These findings suggested the potential involvement of P53 mutations in cutaneous melanoma, highlighting the necessity for further investigations to improve understanding of their roles.

A Prospective Study Between Molecular Marker P53 Analysis and HPE, for Tumour Positivity in Primary Resected Margins in Head and Neck Squamous Cell Carcinoma.

Head and neck malignancies are the seventeenth most common malignancies, worldwide and second most common malignancy in India. So current study aims to compare between molecular marker p53 analysis and HPE for tumour positivity in primary resected margins in head and neck SCC. 61 patients with head and neck SCC were included in this prospective observational cross-sectional study performed in tertiary care hospital. A detailed history general physical examination blood investigation was done before the surgery. After the surgery, primary lesion from the resected tumour was sent for HPE analysis. From the same specimen, the margins at distance of 0.5-1cm from primary tumour were sent for p53 mutation analysis. Report of p-53 mutation was noted and entered to the Performa. In our study we found out that in PDSCC HPE negative margins were found positive for p53 mutation in 81% cases. Which suggest that evaluation for p53 mutation should be done in PDSCC cases for HPE negative margins with in 1cm. In patients of head and neck squamous cell carcinoma with free margins on HPE p-53 mutation is significantly associated to the PDSCC and margin upto 0.7mm so recommended for p-53 profile can be beneficial in cases of the PDSCC and margins up to 0.7mm for further management or for possibility of recurrence and its management to improve patients survival and decrease morbidity and mortality.

Comprehensive analysis of clinicopathologic features and p53 mutation in neuroendocrine neoplasms of the breast: experience from a large academic center.

The recent WHO classification of breast cancer (2019) categorizes breast carcinoma with neuroendocrine (NE) differentiation into three morphologically distinct subtypes: well-differentiated neuroendocrine tumor (NET), poorly differentiated neuroendocrine carcinoma (NEC), and invasive breast carcinoma, no special type with neuroendocrine differentiation (IBC-NST-NE). Data regarding the prognostic significance of neuroendocrine differentiation are conflicting and an association, if any, between p53 mutation and neuroendocrine differentiation is largely unknown. We examined p53 expression and other clinicopathologic characteristics in three types of invasive breast carcinoma with NE differentiation in a cohort of sixty-three patients, including 45 IBC-NST with NE differentiation, 10 NETs, and 8 NECs. No significant difference of clinicopathologic feature was observed between IBC-NST with NE differentiation and NET, but NECs showed significantly lower expressions of hormone receptors, more mutated p53, and higher frequency of distant metastases than IBC-NST with NE differentiation and NETs. NECs of the breast are genetically and clinically different from IBC-NST-NEs and NETs of the breast.

Alterations in p53 Influence hTERT, VEGF and MMPs Expression in Oral Cancer Patients.

Mutant p53 is the crucial molecule in the etiopathogenesis of oral cancer. Therefore, we aimed to evaluate the impact of alterations of the p53 gene and its negative feedback regulator, MDM2, on the expression of hTERT, VEGF, and MMPs; the critical genes involved in oral cancer progression. p53 and MDM2 genotyping were done by PCR-RFLP. p53 mutation analysis was performed using PCR-SSCP and sequencing. hTERT, VEGFA isoforms, MMP2, and MMP9 mRNA levels were analyzed by semi-quantitative Reverse Transcriptase PCR. Arg allele at p53 exon 4 was significantly associated with overexpression of hTERT, MMP2, and MMP9 individually. Expression of hTERT, VEGF A isoforms, MMP2 and MMP9 were significantly altered in the presence of p53 and MDM2 polymorphisms and p53 mutations in a specific combination. Mutant p53, Arg allele at p53 exon 4 locus, and G/G/or T/T genotype at MDM2revealed increased expression of hTERT, VEGF A isoforms, and MMP2/9. This study provides evidence that apart from mutant p53, naturally occurring sequence variants in p53codon 72 (Arg72Pro) (rs1042522) and MDM2 (rs2279744) significantly alter the expression of hTERT, VEGF-A isoforms, and MMP2/9 in a specific combination. The differential interaction of codon 72 variants with MDM2, hTERT, VEGF-A isoforms and MMP2/9 play a role in the aggressiveness of oral cancer. The results have important implications for oral cancer progression and should be explored for innovative treatment options.

De-Intensified (DI) IMPT vs. IMRT(Chemo) for HPV-Associated Oropharynx Cancer (HPV-OPC): Initial Quality of Life (QOL) Results From a Prospective, Multi-Institutional Trial

To compare patient-reported QOL/symptoms between DI IMPT(chemo) and IMRT(chemo) for HPV-OPC.LCCC1612 is a multi-institutional phase II trial of DI RT(chemo) using 60 Gy/30 fx in 6 wk with weekly concurrent cisplatin, 30 mg/m2 for HPV-OPC. Eligible patients (AJCC 8 ed, T0-3, N0-2, M0, p16+, regardless of smoking history) received IMPT at one participating center. T0-2, N1 (single node, < 3 cm) received RT alone. ≥10 pk-y smokers underwent p53 mutation analysis, and only those with wild-type p53 received DI RT(chemo). The IMPT cohort (initial 25 patients with 1y f/u) were matched (2:1) to a randomly selected IMRT cohort using the following: T-class, N-class, and uni- vs. bi-lateral neck RT. QOL/symptoms assessed by EORTC QLQ30, HN35, and EAT-10 were compared at baseline, endRT, 3, 6, and 12 mo. Differences of ≥10 in QLQ30 and HN35 (range, 0-100) and ≥3 in EAT-10 (range, 0-40) were considered clinically relevant.The IMRT cohort consisted of 46 matches (only 1:1 available for 4 IMPT pts). There were no significant differences between non-matched variables (RT dose, chemo, age, gender, smoking history, or primary site). 1-yr PFS was comparable (IMPT, 92%; IMRT, 93%). Only 2/25 (8%) IMPT and 18/46 (39%) IMRT patients required short-term feeding tubes. Both cohorts reported excellent QOL/symptom scores with worse mean scores at end of RT, which returned to baseline by 3 mo for most patients with some exceptions such as dry mouth, sticky saliva, and sensory changes. IMPT resulted in higher (better) mean scores for QLQ30 Global QOL at endRT (55.8/45.8), and role function at endRT (60.1/43.6) and 3 mo (91.7/80.4). Several HN35 mean symptom scores were lower (better) after IMPT including fatigue at endRT (49.3/60.4) and 3 mo (17.2/31.6); appetite loss at 3 mo (16.7/34.8), 6 mo (13.9/27.8), and 12 mo (5.8/16.7); impaired social eating at 3 mo (14.0/30.2) and 6 mo (11.1/22.8); coughing at endRT (29.0/43.2) and 6 mo (15.3/25.6); and feeding tube use at endRT (4.3/34.1) and 3 mo (4.5/15.6). IMPT patients reported less dysphagia with lower mean EAT-10 scores at 3 mo (5.8/10.0) and 6 mo (4.5/8). Narcotic use was higher with IMPT than IMRT at end RT and 3 mo without a difference in pain scores. There was no difference in financial difficulties despite the added costs with proton therapy.DI IMPT(chemo) and IMRT(chemo) resulted in favorable patient-reported QOL/symptoms with most patients reporting return to baseline QOL/symptom scores by 3 mo with some exceptions. DI IMPT(chemo) resulted in very low rate of feeding tube use and less swallowing/eating-related symptoms compared with IMRT(chemo) using independently validated instruments. Additional data and long-term follow-up will be needed to validate these findings and confirm the long-term safety/efficacy of DI RT(chemo).

New Plausible Mechanism for Gastric and Colorectal Carcinogenesis: Free Radical-Mediated Acetaldehyde Generation in a Heme/Myoglobin-Linoleate-Ethanol Mixture.

Epidemiological studies have revealed that alcohol, red meat, and cooking oil (or linoleate) are risk factors for both gastric and colon cancers. A survey of the mutation spectra of the p53 tumor suppressor gene in these cancers suggested that the types of mutations and the hot spots are similar to those induced by acetaldehyde (AcAld) in an in vitro p53 mutation analysis system. Accordingly, various combinations of possible factors, components, or model compounds were reacted in an emulsion and tested for the generation of AcAld. Efficient AcAld formation was only observed with combinations of three factors, red meat homogenate (or heme/myoglobin), methyl linoleate, and ethanol, but not by any combination of the two. The generated AcAld levels (ca. 500 μM) far exceeded the minimum mutagenic concentration (40–100 μM) obtained using concentrations of meat homogenate (or heme/Mb), linoleate, and ethanol comparable to those in the stomach after an ordinary meal. A mutagenic level of AcAld (75 μM) was also generated with a physiological concentration of ethanol, heme, and linoleate in the colon. As a mechanism, linoleate hydroperoxide formation and its decomposition in the presence of myoglobin (or heme) to generate the OH radical seem to be involved in the ethanol-to-AcAld conversion.

Clinical application of TCGA molecular classification in endometrial endometrioid carcinoma

Objective: To explore molecular characteristics of endometrial endometrioid cancer according to The Cancer Genome Atlas (TCGA) based molecular classification of endometrial carcinomas and to confirm simple and clinically applicable surrogate methodologies in pathological practice. Methods: Two hundred and twenty-eight cases of endometrial endometroid adenocarcinomas (EnACs) collected from August 2001 to August 2017 from Peking University Health Science Center, Peking University Third Hospital were molecularly categorized by using Sanger sequencing for the exonuclease domain mutations (EDM) of POLE, and by immunohistochemistry for p53 and mismatch repair (MMR) proteins. The cohort was classified into polymerase-E exonuclease domain mutation (POLE EDM), mismatch repair deficiency (MMR-D), p53 abnormal (p53-abn) and p53 wild type (p53-wt) groups. The correlation between molecular subgroups and the clinical-pathological features including prognosis were analyzed. Results: The cohort was distributed as follows: 11(4.8%) POLE EDM, 47(20.6%) MMR-D, 9(4.0%) p53-abn and 161(70.6%) p53-wt. p53-wt subgroup patients demonstrated significantly higher lymph node metastasis (P=0.011) and more advanced stage (P=0.036) than those of somatic hypermutation group cases (POLE EDM and MMR-D). In the FIGO grade 2-3 EnACs cohort, TCGA molecular subtyping was significantly correlated with progression-free survival and overall survival (P=0.043). POLE EDM subgroup had the best survival, while p53-abn subgroup had the worst. Conclusions: Identification of POLE EDM and MMR-D subgroups provides independent and highly valuable prognostic information beyond established histological classification. Based on immunohistochemistry of MMR, p53 and POLE mutational analysis, this pragmatic molecular classification scheme can be served as a reliable surrogate for TCGA molecular classification, which has potential to be used routinely in Chinese pathological practice.

Abstract 3728: Inverse effect of 28Si and 56Fe radiation on intestinal tumorigenesis vs. carcinogenesis in APC1638N/+ mice

Abstract Space radiation is a major risk factor for gastrointestinal (GI) cancer in astronauts and is a matter of concern. Earlier we have reported higher relative effects for intestinal tumorigenesis in APC1638N/+ mice after exposure to different heavy ion radiation spanning a range of LET values. The purpose of the current study was to histologically grade intestinal tumors into adenoma vs. adenocarcinoma and assess relative effects of different heavy ion radiation on tumorigenesis vs carcinogenesis. Tumors from male APC1638N/+ mice 150 d after exposure to whole-body sham, γ (0.3 keV/μm), 12C (13 keV/μm), 28Si (70 keV/μm), or 56Fe (148 keV/μm) radiation were harvested, fixed, paraffin embedded, and sectioned. Radiation doses were 0.1 Gy, 0.5 Gy and a equitoxic dose of 2.0 Gy γ-rays. H&amp;E stained tumor sections from at least 50 tumors per study group were used for histological grading into adenoma and adenocarcinoma. Hotspot mutations for p53 and Kras genes were assessed using targeted PCR followed by amplicon sequencing in 20 tumors per study group. Our previous published data showed that among the three LETs tested relative intestinal tumorigenic effects (relative to γ-rays) peaked at a LET of 70 keV/μm (28Si) with 13 keV/μm (12C) showing the least effect and 148 keV/μm (56Fe) showing an intermediate effect. In contrast, the current study demonstrates that the frequency of adenocarcinoma peaked after 56Fe with the least effect after 12C and an intermediate effect after 28Si. Relative to γ-rays, the carcinoma frequencies were 42.4+0.9, 13.2+0.61 and 8.0+1.14 higher after 56Fe at doses of 0.1, 0.5 and 2.0 Gy respectively. Whereas the relative carcinoma frequencies of 34.2+1.35, 14.0+0.95 and 9.0+2.25 were observed after 28Si at doses of 0.1, 0.5 and 2.0 Gy respectively. While Kras mutation analysis of tumors did not show any difference among radiation types, p53 mutation analysis demonstrate a higher number of mutations in exon 5 in 56Fe relative to 28Si samples. Collectively, our data show that while LET-dependent tumorigenic effects followed a parabolic shape, carcinogenic effects followed a more linear-like pattern with highest adenocarcinoma percentage and frequency at 148 keV/μm (56Fe). Although inverse effects of LET on tumorigenesis vs. carcinogenesis could in part be attributed to the beams’ differential physical properties, our mutation data on p53 supports differential effects of the beams on tumor suppressor mutation. Citation Format: Santosh Kumar, Shubhankar Suman, Bhaskar V.s. Kallakury, Bo-Hyun Moon, Albert J. Fornace, Kamal Datta. Inverse effect of 28Si and 56Fe radiation on intestinal tumorigenesis vs. carcinogenesis in APC1638N/+ mice [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3728.

Comprehensive genomic profiling of recurrent endometrial cancer: Implications for selection of systemic therapy

ObjectivesTo assess whether comprehensive genomic profiling (CGP) in the setting of routine clinical care allows molecular classification of recurrent endometrial cancer (EC) into the four Cancer Genome Atlas (TCGA) categories: POLE ultramutated, microsatellite instable, copy-number low, and copy-number high and whether this approach can identify genomic alterations (GAs) which inform treatment decisions. MethodsArchival tissues from 74 patients diagnosed with recurrent EC were prospectively analyzed using hybrid-capture-based genomic profiling. Tumor mutational burden and microsatellite instability were measured. Clinically relevant GAs (CRGAs) were defined as GAs associated with targeted therapies available on-label or in mechanism-driven clinical trials. ResultsUsing POLE mutational analysis, mismatch repair status, and p53 mutational analysis as surrogate for ‘copy-number’ status CGP segregated all cases into four TCGA molecular subgroups. While recurrent serous ECs were predominantly copy-number high, we found no clear prevalence of a specific molecular subtype in endometrioid, clear cell or undifferentiated tumors. Every tumor sample had at least one GA and 91% (67/74) had at least one CRGA. In this series 32% (24/74) of patients received a matched therapy based on the results of CGP. Objective responses to the matched therapy were seen in 25% (6/24) of patients with an additional 37.5% (9/24) achieving stable disease leading to a clinical benefit rate of 62.5% with a median treatment duration of 14.6 months (range 4.3–69 months). ConclusionsCGP allows molecular classification of EC into four TCGA categories and allows identification of potential biomarkers for matched therapy in the setting of routine clinical care.

Identification and Characterization of Synthetic Viability with ERCC1 Deficiency in Response to Interstrand Crosslinks in Lung Cancer.

ERCC1/XPF is a DNA endonuclease with variable expression in primary tumor specimens, and has been investigated as a predictive biomarker for efficacy of platinum-based chemotherapy. The failure of clinical trials utilizing ERCC1 expression to predict response to platinum-based chemotherapy suggests additional mechanisms underlying the basic biology of ERCC1 in the response to interstrand crosslinks (ICLs) remain unknown. We aimed to characterize a panel of ERCC1 knockout (Δ) cell lines, where we identified a synthetic viable phenotype in response to ICLs with ERCC1 deficiency. We utilized the CRISPR-Cas9 system to create a panel of ERCC1Δ lung cancer cell lines which we characterized. We observe that loss of ERCC1 hypersensitizes cells to cisplatin when wild-type (WT) p53 is retained, whereas there is only modest sensitivity in cell lines that are p53mutant/null. In addition, when p53 is disrupted by CRISPR-Cas9 (p53*) in ERCC1Δ/p53WT cells, there is reduced apoptosis and increased viability after platinum treatment. These results were recapitulated in 2 patient data sets utilizing p53 mutation analysis and ERCC1 expression to assess overall survival. We also show that kinetics of ICL-repair (ICL-R) differ between ERCC1Δ/p53WT and ERCC1Δ/p53* cells. Finally, we provide evidence that cisplatin tolerance in the context of ERCC1 deficiency relies on DNA-PKcs and BRCA1 function. Our findings implicate p53 as a potential confounding variable in clinical assessments of ERCC1 as a platinum biomarker via promoting an environment in which error-prone mechanisms of ICL-R may be able to partially compensate for loss of ERCC1.See related commentary by Friboulet et al., p. 2369.

Genetic and Immunohistochemical Studies Investigating the Histogenesis of Neuroendocrine and Carcinomatous Components of Combined Neuroendocrine Carcinoma.

Lung combined neuroendocrine carcinomas (NECs) comprise NEC and non-NEC components, such as adenocarcinoma and squamous cell carcinoma. Mutation of epidermal growth factor receptor (EGFR) often is observed in non-NEC but is very rare in sporadic NEC, which almost always has p53 mutation. Therefore, we hypothesized the following research concept: mutation analysis of EGFR and p53 in each component of combined NEC tissues can provide important information on whether such components originate from the same tumor cells or incidentally arise as collision cancers. We compared the mutations of EGFR and p53 in laser-microdissected NEC and non-NEC from lungs of eight cases affected by combined NEC. We examined the expression of EGFR and NEC markers in the combined NECs by immunohistochemistry. Five of eight cases of combined NEC had the same mutations of EGFR and/or p53 in both non-NEC and NEC. One case had EGFR mutation in only the non-NEC component, and two cases did not have these mutations. Replacement transformation was observed in borderline areas between non-NEC and NEC. The signal of activated EGFR in non-NEC with the same EGFR mutation was more intense than that in NEC components. Our study suggests the mechanism behind the carcinogenesis of lung combined NEC, which is partially caused by the transformation from epithelial carcinoma of non-NEC to NEC.

Clinicopathologic features and BRCA mutations in primary fallopian tube cancer in Japanese women.

The present study aimed to clarify the clinicopathological features, including the level of p53 protein expression and BRCA mutations, of primary fallopian tube cancer (PFTC) in Japanese women. A multicenter clinical survey was conducted at three Japanese institutions. Clinical data in patients with PFTC between 1998 and 2016 were collected. Immunohistochemical staining of p53 and BRCA mutation analysis by exome sequence using paraffin-embedded surgical resected specimens were performed. A total of 40 patients with PFTC were enrolled in the study. The median age was 58 years (range: 38-78 years); 31 patients were menopausal. Thirty-four (85.0%) patients were diagnosed with serous adenocarcinoma (high grade, 33; low grade, 1). PFTC was classified into ampulla type, fimbriae type and undeterminable type by tumor-occupying lesion; ampulla type and fimbriae type occurred with the same frequency. Among 30 patients with high-grade serous adenocarcinoma, 6 patients showed germline mutations of BRCA1 (stop-gain 4 and frameshift deletion 2) and 2 patients showed germline mutation of BRCA2 (stop-gain 1 and frameshift deletion 1). However, only 1 patient had familial history of breast or ovarian cancer. Patients with BRCA mutations in the germline were frequently observed in ampulla type and FIGO stage I/II cancers, but no significant difference in the frequency of p53 overexpression and overall survival was observed. Among Japanese patients with PFTC, 26.7% presented with BRCA mutations in the germline. Additionally, p53 was important for the carcinogenesis in fallopian tubes, independent of the specific BRCA mutation.

Expression patterns and mutation analysis of p53 in fish Rita rita from polluted riverine environment

The present study was undertaken to investigate the alterations in gene expression patterns and for mutation analysis of p53 in the riverine catfish Rita rita collected from polluted riverine habitat. The partial p53 gene sequence of Rita rita generated showed a high degree of similarities with the DNA binding domains of fishes, mice and human. Transcriptomic analysis, carried out by quantitative real-time Polymerase Chain Reaction (RT-qPCR), showed significant down-regulation of p53 in fishes collected from most of the polluted stretches. Similar trend in protein abundance was observed by western blot analysis. Down-regulation of p53 was more pronounced in gill than liver. Expression patterns of p53 suggest that exposure to a multitude of contaminants in the natural riverine ecosystem could suppress the expression of p53. Genomic DNA showed a low stained smear pattern upon electrophoresis, with no evidence of DNA fragmentation. For mutation analysis PCR-SSCP followed by sequence analysis was carried out, which identified eight mutations; two at codon level and six missense mutations in the DNA binding domain IV and V. Secondary structure prediction showed that these mutations could lead to impairment of protein structure. Thus, the present study indicated that aquatic pollution has impacted these lower vertebrates which are reflected by the down-regulation of tumor suppressor protein (p53) in majority of the stretches studied.

Abstract 3225: SHetA2 targets mortalin-p53 interaction in differential induction of apoptosis in ovarian cancer over normal cells

Abstract Introduction: Identical TP53 mutations observed in fallopian tube pre-neoplastic lesions and high grade serous ovarian cancer (HGSOC) from the same patient suggest that these mutations drive ovarian carcinogenesis. While elevated p53 protein expression caused by these mutations increase cell survival, persistently high levels can cause apoptosis. Mortalin (HSPA9) is a chaperone protein which plays a major role in protecting cancer cells from p53-mediated apoptosis by binding to p53 and preventing it from translocating to the nucleus where it transactivates apoptosis-inducing genes and to the mitochondria where it inhibits Bcl-2 and induces Bax pore formation. SHetA2 is an anti-cancer drug that binds mortalin and induces apoptosis in cancer, but not in normal cells. We hypothesized that release of p53 from mortalin contributes to the mechanism of SHetA2-induced apoptosis in cancer, but not in normal cells. Methods: SHetA2 effects on mortalin and p53 interaction and subcellular localization were evaluated by co-immunoprecipitation in cell extracts and fluorescent cytochemistry of human ovarian cancer cell lines and tissues and human fallopian tube secretory epithelial cells (hFTSECs) cultures and tissues. Effects of SHetA2 and manipulations of mortalin and p53 expression, function and localization in ovarian cancer cells were measured using the MTS dye to detect viable cells, Flow cytometric analysis of Annexin-V/PI cell staining to detect apoptosis and a PCR array to measure p53 regulated gene expression. Results: Mortalin bound to p53 in protein extracts of cultures and tissues from ovarian cancer, but not from hFTSECs. SHetA2 caused dose-responsive apoptosis in association with nuclear and mitochondrial accumulation of p53 in ovarian cancer cell lines harboring wild type or S215R, L130V TP53 mutants, but not in hFTSECs. Mortalin overexpression or p53 knockdown reduced SHetA2 cytotoxicity in ovarian cancer cells. Mortalin knockdown, p53 overexpression, and chemical inhibitors of p53 transcription (Pifithrin-α) and p53 mitochondrial localization (Pifithrin-µ) were lethal to ovarian cancer cells at effective concentrations and therefore ineffective tools for probing the SHetA2 apoptosis mechanism. In the A2780 cell line containing wild type p53, SHetA2 caused ≥2 fold regulation of p53 signaling genes (p21, FOXO3, IGF1R, MDM4, SESN2, SIAH1, DR5, CAPS2, CCNE1, CDC25A, E2F1, PCNA and TP63). Our analysis of p53 mutations using The Cancer Genome Atlas (TCGA) data revealed that majority of HGSOC exhibited p53 mutations spanning from exon 3-9, with the majority being missense mutations in the DNA binding domain associated with increased protein stability and gain of function. Conclusion: Release of wild type and mutant p53 proteins from mortalin contributes to the mechanism of SHetA2-induced apoptosis in cancer cells and does not occur in healthy cells. Funded by R01CA196200. Citation Format: Satish Kumar Ramraj, Richard Pelikan, Vishal Chandra, Doris Benbrook. SHetA2 targets mortalin-p53 interaction in differential induction of apoptosis in ovarian cancer over normal cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 3225. doi:10.1158/1538-7445.AM2017-3225

The diagnosis of a metastatic breast tumor from ovarian cancer by the succession of a p53 mutation: a case report

BackgroundMetastatic breast tumors from other organs are very rare. We herein describe the case of a patient with a metastatic breast tumor due to ovarian cancer who was diagnosed by the succession of a p53 mutation.Case presentationThe patient was a 59-year-old woman with sigmoid colon stenosis. Diagnostic imaging revealed a pelvic mass, multiple liver tumors, ascites, and multiple swollen para-aortic lymph nodes, suggesting an advanced ovarian tumor. Transverse loop colostomy and partial resection of the greater omentum was performed followed by six cycles of paclitaxel with carboplatin chemotherapy (TC therapy). Her cancer almost disappeared, with the exception of a small tumor in her pelvis. Simple hysterectomy with bilateral salpingo-oophorectomy was performed. Two years and 5 months after the second surgery, a mass was detected in her right breast and simple mastectomy was performed. A histological examination of the tumors from the first surgery revealed infiltrating papillary adenocarcinoma and the solid nest proliferation of atypical cells with comedo necrosis and psammoma bodies. The findings of an immunohistochemical analysis were as follows: cancer antigen 125 (CA125 (+)), cytokeratin 7 (CK7 (+)), cytokeratin 20 (CK20 (−)), p53 (+) and CDX2 (−), estrogen receptor (ER (slightly +)), progesterone receptor (PR (slightly +)), and human epidermal growth factor receptor 2 (HER2 (1+)). The breast tumors presented similar morphological features (ER (−), PR (−), HER2 (−), CA125 (+), CK7 (+), CK20 (−), p53 (+), mammaglobin (−), and GCDFP15 (−)), which were not characteristic of breast cancer. A direct sequencing analysis of p53 revealed a p.V173M mutation in exon 5 in both the breast tumor and the ovarian cancer. It was not detected in normal tissue, suggesting that the breast tumors were metastatic serous adenocarcinomas from ovarian cancer.ConclusionsA direct sequencing mutation analysis of p53 was useful for distinguishing the primary tumor from the metastatic tumor. We should resect metastatic breast tumors to the extent that is possible because the prognosis of such patients is relatively good.

Impact of Molecular Predictors on the Response Rates in Head and Neck Cancer Patients - an Observational Study.

Squamous cell carcinoma of head and neck region account for more than 25 % of male and more than 10 % of female cancers in India (1). Head and neck cancer treatment includes a multidisciplinary approach involving all specialties. Concurrent chemo-radiation is the standard of care in most of the subsites (2). Inspite of the multi-disciplinary approach, a plateau has been reached in terms of results with 5 year survival of locally advanced disease of around 30 % (3). In order to improve outcomes, there has been considerable interest in molecular profiling of head and neck cancers 4-10. However there is still significant paucity in terms of Indian data, hence the need for the study. The objectives are to assess the HPV-p16, EGFR and p53 status, to correlate HPV-p16, EGFR and p53 status with the response rates, to correlate HPV-p16,EGFR and p53 status with other factors like age, sex, tobacco use. Twenty five consecutive cases of histopathologically proven head and neck cancers were accrued. All patients were treated with external radiation to a dose of 66Gy in 33 fractions along with concurrent weekly cisplatin chemotherapy at a dose of 40mg/sqm. HPV-p16, EGFR and p53 mutation analysis was done on paraffin embedded histopathological blocks. PCR technique used for HPV-p16, EGFR and p53 status detection. Response assessment was done based on RECIST criteria. Correlation of HPV, EGFR and p53 status on response was done. The EGFR positivity rate was 84 %, the p53 positivity rate was 76 % and the HPV p-16 positivity rate was 28 %. Out of 25 patients, 13(52%) had complete response, 7(28 %) had partial response, 3(12 %) had stable disease and 2(8 %) had progressive disease. On correlation of molecular profile with response, there was no statistical significance between EGFR status and response (p 0.5) or HPV-p16 and response (p 0.8). However, p53 positivity was approaching significance with respect to good response (p 0.07).

Intercalated EGFR TKI and chemotherapy induction therapy in EGFR mt+ NSCLC stage IIIA and IIIB: report of 5 cases.

e20059Background: EGFR TKI treatment is standard of care in metastatic EGFR mt+ NSCLC. Recently new focus has been shed on intercalated regimens of chemotherapy and TKI, showing improved PFS as well as OS. This concept was used as induction regimen in 5 EGFR mt+ pts in stages IIIA/B and is now continued as a phase II study (NeoIntercal). Methods: Patients were diagnosed and worked up according to standard imaging, histology and IHC methods. EGFR, KRAS, BRAF, ALK and P53 mutation analysis were performed by standard procedures. Regression grading was assessed by Junker criteria. Results: 3 f never smokers (pt #1, #3, #5), ages 59, 62 and 62 y, 2 m light smokers (pt#2 and #4) 58 and 69 years had non-squ. NSCLC, 2 with exon 21 L858R (#1,2) and 3 with exon 19 del (#3,4,5). 4/5 patients carried a p53 mutation, disruptive pt #1, non-disruptive pts.#2-4, p53WT #5. Tumor stages were IIIB in pts. #1, 2, 5, IIIA pt. #3, OMD pt. #4. Induction therapy was erlotinib 150 mg/die p.o. (pts #2,3) /gefitinib 250 mg/die p.o....

P53 Mutant Independently Impacts Risk: Analysis of Deletion 5q, Lower-Risk Myelodysplastic Syndromes (MDS) Patients Treated with Lenalidomide (LEN) in the MDS-004 Study

▪Introduction: Refined risk-classification of patients (pts) with MDS allows for improved treatment selection for individual pts. The Revised International Prognostic Scoring System (IPSS-R) has recently been validated as a prognostic tool in lower-risk MDS pts with deletion 5q [del(5q)], who were treated with LEN in the MDS-004 study (Sekeres et al. Blood Cancer J 2014; in press). P53 nuclear protein expression, as assessed by immunohistochemistry (IHC), predicted overall survival (OS) and risk of progression to acute myeloid leukemia (AML) in lower-risk MDS pts with del(5q) (Saft et al. Haematologica 2014;99:1041-9). This analysis evaluated the prognostic value of adding p53 IHC to IPSS-R to predict OS and AML progression in pts with lower-risk MDS with del(5q).Methods: In a subset of 85 pts from MDS-004 with bone marrow (BM) biopsies available, p53+ staining (≥ 1% IHC+++ BM cells) was visualized by IHC. Twenty-four pts had missing IPSS-R scores; 1 due to lack of baseline cytogenetic data and 23 because of missing exact BM blast percentage. Thus, 61 pts (42 initially treated with LEN and 19 with placebo) had IPSS-R and p53 IHC data available; 89% of pts in the placebo group crossed over to LEN 5 mg at Week 16. The IPSS-R Very Low and Very High risk groups with < 5 pts were combined with the Low and High risk groups, respectively. AML-free survival (AFS), OS, and time to AML progression within p53 IHC status (p53+ vs p53−), and IPSS-R risk groups were characterized by the Kaplan-Meier method with differences evaluated by the log-rank test.Results: Of 61 pts, 38% were p53+. There was a linear increasing trend in the proportion of pts with p53+ across IPSS-R risk groups from Very Low/Low, Intermediate to High/Very High (29%, 47% and 63%, respectively; Cochran-Armitage trend test P = 0.050). The 3 IPSS-R risk groups significantly predicted AFS and OS (log-rank P < 0.001 for both AFS and OS), but not time to AML progression (P = 0.335). Overall, AFS, OS, and time to AML progression differed significantly between p53+ versus p53− pts (23.9 vs 47.9 months for median AFS, P = 0.003; 27.0 vs 50.6 months for median OS, P = 0.005; and 44.3 months vs not reached [NR] for median time to AML progression,P = 0.003). In the IPSS-R Very Low/Low risk group (n = 38), AFS, OS, and time to AML progression were significantly worse in p53+ versus p53− pts (20.1 vs 63.1 months for median AFS, P = 0.011; 28.4 vs 76.8 months for median OS, P = 0.031; and 65.2 months vs NR for median time to AML progression, P = 0.014). Results for all IPSS-R risk groups in pts with p53 and IPSS-R data are presented in the Figure. The lack of significant differences between p53+ versus p53− pts in the Intermediate and High/Very High risk groups is likely due to the small sample size of these groups.Conclusions: In this exploratory subset analysis of lower-risk MDS pts with del(5q), p53 IHC status in the IPSS-R Very Low/Low risk group significantly impacted AFS, OS, and AML progression. These data support the addition of p53 mutational analysis to prognostic risk assessment which should help inform the selection of appropriate treatment for individual MDS pts with del(5q). These results need to be validated in a large sample set, which will be accomplished as part of the ongoing efforts to include prognostic molecular mutations in future updates of IPSS-R [Display omitted] [Display omitted] [Display omitted] DisclosuresShiansong Li:Celgene Corporation: Employment, Equity Ownership. Greenberg:Celgene: Research Funding; Onconova: Research Funding; GSK: Research Funding; Novartis: Research Funding; KaloBios: Research Funding. Sekeres:Amgen Corp.: Membership on an entity’s Board of Directors or advisory committees; Boehringer-Ingelheim Corp.: Membership on an entity’s Board of Directors or advisory committees; Celgene Corporation: Membership on an entity’s Board of Directors or advisory committees. Dreyfus:Novartis: Honoraria; Celgene: Honoraria. Fenaux:Novartis: Research Funding; Janssen: Research Funding; Celgene: Research Funding. Swern:Celgene: Employment, Equity Ownership. Sugrue:Celgene: Employment, Equity Ownership. Hellstrom-Lindberg:Celgene: Research Funding.

Discrimination of p53 immunohistochemistry-positive tumors by its staining pattern in gastric cancer.

Immunohistochemistry staining of p53 is a cheap and simple method to detect aberrant function of p53. However, there are some discrepancies between the result of immunohistochemistry staining and mutation analysis. This study attempted to find a new definition of p53 staining by its staining pattern. Immunohistochemistry staining of p53 and TP53 gene mutation analysis were performed in 148 gastric cancer patients. Also SNP-CGH array analysis was conducted to four cases. Positive staining of p53 was observed in 88 (59.5%) tumors. Tumors with positive p53 staining showed malignant features compared to negative tumors. Mutation of TP53 gene was observed in 29 (19.6%) tumors with higher age and differentiated type. In positive p53 tumors, two types could be distinguished; aberrant type and scattered type. With comparison to TP53 gene mutation analysis, all the scattered type had wild-type TP53 gene (P = 0.0003). SNP-CGH array showed that scattered-type tumors had no change in the structure of chromosome 17. P53-scattered-type staining tumors may reflect a functionally active nonmutated TP53 gene. In interpretation of p53 immunohistochemistry staining, distinguishing p53-positive tumors by their staining pattern may be important in gastric cancer.

New Aspects of the Clinicopathology and Genetic Profile of Metachronous Multiple Lung Cancers

For treatment decisions and prognostic applications, we evaluated p53/epidermal growth factor receptor (EGFR) somatic aberrations in metachronous multiple lung cancers to differentiate multiple primary lung cancers (MPLCs) from pulmonary metastases. The current criteria to differentiate MPLCs from metastases are based on the histologic type and onset interval and do not incorporate genetic analysis. The genetic background of MPLCs remains unclear. Ninety-seven metachronous multiple lung cancers were identified to investigate somatic mutations in p53 and EGFR. Mutational analysis of p53 and EGFR was performed on DNA extracted from paraffin-embedded tumors. A high frequency of somatic mutations in p53 (44.3%; 43/97) and/or EGFR (51.5%; 50/97) resulted in a high discrimination rate of tumor clonality (77.3%; 75/97) in metachronous multiple lung cancers. Of the 97 cases, 25 cases (33.3%) and 50 cases (66.7%) were assessed as having the same clonality (SC) and different clonality (DC), respectively. Notably, DC was commonly observed among tumors of the same histologic type (60.7%; 37/61), which further supported the carcinogenic theory of field cancerization. Multivariate analysis revealed that a first primary tumor of 3 cm or smaller (5-year survival: 92.7%; P = 0.001) and a limited resection of the latest tumor (5-year survival: 96.0%; P = 0.016) were 2 independent predictors of favorable prognosis. Because most metachronous tumors of the same histologic type have different clonal origins, clonality assessment is essential to differentiate MPLCs from metastases. We recommend limited resection as the treatment of choice to achieve long-term survival in MPLCs patients with tumors of 3 cm or smaller.