Claudins in Cancer: A Current and Future Therapeutic Target

Claudins are a family of 27 proteins that have an important role in the formation of tight junctions. They also have an important function in ion exchange, cell mobility, and the epithelial-to-mesenchymal transition, the latter being very important in cancer invasion and metastasis. Therapeutic targeting of claudins has been investigated to improve cancer outcomes. Recent evidence shows improved outcomes when combining monoclonal antibodies against claudin 18.2 with chemotherapy for patients with gastroesophageal junction cancer. Currently, chimeric antigen receptor T-cells targeting claudin 18 are under investigation. In this review, we will discuss the major functions of claudins, their distribution in the normal as well as cancerous tissues, and their effect in cancer metastasis, with a special focus on the therapeutic targeting of claudins to improve cancer outcomes.

Mutations highly specific for secondary AML are associated with poor outcomes in ELN favorable risk NPM1-mutated AML

ABSTRACT

Acute myeloid leukemia (AML) is a heterogeneous malignancy with outcomes largely predicted by genetic abnormalities. Mutations of NPM1 are common in AML, occurring in ∼30% of cases, and generally considered a favorable risk factor. Mutations highly specific for secondary AML (sMut) have been shown to confer poor prognosis, but the overall impact of these mutations in the setting of favorable-risk AML defined by mutant NPM1 remains unclear. In this multicenter study of patients with AML (n = 233) with NPM1 mutation at diagnosis, we observed that patients with sMut had worse overall survival (OS) than those without sMut (15.3 vs 43.7 months; P = .002). Importantly, this finding persisted in the European LeukemiaNet (ELN) 2017-defined favorable risk subset (14.7 months vs not reached; P < .0001). Among patients who achieved NPM1 measurable residual disease (MRD) negativity, longer OS was observed in the entire cohort (P = .015) as well as in both the sMut subset (MRD negative: median OS (mOS) 73.9 months vs MRD positive: 12.3 months; P = .0170) and sMut ELN 2017-favorable subset (MRD negative: mOS 27.3 vs MRD positive: 10.5 months; P = .009). Co-occurrence of sMut and mutant NPM1 confers a poor prognosis in AML.

Therapeutic Targeting of Hypoxia-Inducible Factors in Cancer

In the realm of cancer therapeutics, targeting the hypoxia-inducible factor (HIF) pathway has emerged as a promising strategy. This study delves into the intricate web of HIF-associated mechanisms, exploring avenues for future anticancer therapies. Framing the investigation within the broader context of cancer progression and hypoxia response, this article aims to decipher the pivotal role played by HIF in regulating genes influencing angiogenesis, cell proliferation, and glucose metabolism. Employing diverse approaches such as HIF inhibitors, anti-angiogenic therapies, and hypoxia-activated prodrugs, the research methodologically intervenes at different nodes of the HIF pathway. Findings showcase the efficacy of agents like EZN-2968, Minnelide, and Acriflavine in modulating HIF-1α protein synthesis and destabilizing HIF-1, providing preliminary proof of HIF-1α mRNA modulation and antitumor activity. However, challenges, including toxicity, necessitate continued exploration and development, as exemplified by ongoing clinical trials. This article concludes by emphasizing the potential of targeted HIF therapies in disrupting cancer-related signaling pathways.

Pancreatic adverse events in patients treated with immune checkpoint inhibitors

Background and Aim

The inhibition of cytotoxic T-lymphocyte associated antigen-4 (CTLA-4) and programmed cell death-1 (PD-1) has been a target for multiple drugs to enhance the T-cell antitumor activity. However, these immune checkpoint inhibitors (ICIs) come with a panel of immune-related adverse events (irAEs) that include mainly endocrine, skin, and gastrointestinal effects. We report seven cases of pancreatic irAEs in patients treated with ICIs at our institute.

Methods

This is a case series; data was collected through chart review by 3 different data collectors and was analyzed separately by 2 physicians.

Results

Of these seven cases, two had diabetic ketoacidosis (DKA), while five had pancreatitis diagnosed by a substantial rise in serum lipase. Pancreatitis was asymptomatic in two cases. A pancreatic biopsy in one case revealed type 2 autoimmune pancreatitis. The ICIs used included pembrolizumab, nivolumab, durvalumab, and avelumab. Treatment included steroids and holding the ICI therapy: three cases had complete resolution of pancreatitis while two cases required either a prolonged taper or a second course of prednisone for recurrence of pancreatitis. On the other hand, the DKA cases were treated with withdrawal of the ICI and starting insulin with no steroid therapy.

Conclusions

Pancreatitis and DKA are rare adverse events of ICIs that can be controlled by holding the ICI with or without starting steroids. Rechallenging the patient with the same ICI is possible in selected cases.

A retrospective analysis of gender disparities in clinical outcomes of patients diagnosed with non-uterine leiomyosarcoma

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Background: The effect of gender in sarcoma patients in various organ systems has been the subject of several studies, many of which show no overall survival (OS) difference between male and female genders. Tumor size and grade have been noted to be independent predictors of local recurrence and disease specific survival in a prospective study of patients with non-uterine leiomyosarcoma by Gaddy et. al. however, gender had no effect on OS. Methods: The 2004-2016 National Cancer Database (NCDB) was queried for males with leiomyosarcoma (LMS) and females with extrauterine leiomyosarcoma (EULMS) using topographical codes C490-C496, and C498-C499. Data included: patient’s age, race, year at diagnosis, tumor grade, size and stage, lymph node involvement, receipt of surgical treatment, chemotherapy or palliative care treatment, surgical margins, time to treatment in days, OS (months between the date of diagnosis and date of death or censored at last contact), and long-term survival defined as survival for 60 months or more. Univariate analysis was used to determine significant predictors of binary survival status (i.e. alive or dead), significant factors were then included in a multivariate analysis. Using Stata/SE 15.1, Kaplan-Meier (KM) method with log-rank test was used to compare and estimate OS rates between the 2 groups. Results: The total number of patients was 13537, with 6311 males (46.6%) and 7226 females (53.4%). The OS in females was 57.2 months compared to 72.0 months in males (P < 0.001). Men were also more likely to achieve long-term survival (36.1%) compared to females (34.4%, P < 0.001). Men with LMS had a lower percentage of chemotherapy use compared to females (18.7% vs 25% respectively, P < 0.001) and palliative care use (3.0% vs 3.5%; P = 0.013). Lower likelihood of survival among both groups was noted in older age (OR = 0.96; P < 0.001 in males; OR = 0.97, P < 0.001 in females), tumor stage > I (OR = 0.64, P = 0.005 in males; OR = 0.56, P < 0.001 in females) and positive surgical margins (OR = 0.76, P = 0.013 in males; OR = 0.87, P = 0.009 in females). Contrarily, increasing year of diagnosis was associated with an increased likelihood of survival (OR = 1.51, P < 0.001 in males; OR = 1.27, P < 0.001 in females). Larger tumor size was also associated with decreased likelihood of survival, but only in the female group (OR = 0.39, P = 0.001). Conclusions: Our analysis shows that males with LMS had a higher OS and higher percentage of long-term survival compared to females. The only factor affecting survival that was different between the 2 groups was the tumor size, which was associated with significantly decreased likelihood of survival in females. No clear explanation for this different survival could be extrapolated from the clinical data collected. Further studies are recommended to investigate the genetic, epigenetic, and possibly hormonal factors that may affect survival in LMS.

Differential outcome of females with uterine versus extra-uterine leiomyosarcomas, a retrospective analysis

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Background: Leiomyosarcomas, are aggressive sarcomas with survival rates among the lowest of all soft tissue sarcomas. Patients with uterine leiomyosarcoma (ULMS) have worse overall survival (OS) than those with extra-uterine leiomyosarcoma (EULMS). The effect of several clinical factors on OS have been investigated, including age, tumor size, grade, stage, and use of chemotherapy. Looking at the epigenetics of the 2 diseases, differentially methylated regions (DMRs) were statistically significant between the 2 groups. Methods: The 2004-2016 National Cancer Database was queried for females with ULMS and EULMS. We investigated several factors as predictors of binary survival status (alive or dead): patient’s age, race, year at diagnosis, tumor grade, size and stage, receipt of surgical treatment, chemotherapy, palliative care, surgical margins and time to treatment in days. Univariate and backward stepwise multivariate logistic regression models were used to determine prognostic factors associated with survival in each group. Kaplan-Meier (KM) method with log-rank test was used to compare OS rates between the 2 groups. All analyses were conducted using Stata/SE 15.1. Results: The total number of subjects was 16883. The median OS was 36.7 months in ULMS vs 57.2 in EULMS (P < 0.001). Older age was associated with a lower likelihood of survival in both groups (OR = 0.95, P = 0.018 in ULMS; OR = 0.97, P < 0.001 in EULMS). Lymphovascular invasion and receipt of palliative care were associated with a relatively large decrease in survival in ULMS only (OR = 0.25, P < 0.001; OR = 0.13, P = 0.015 respectively). In the EULMS group, increased likelihood of survival was associated with later years of diagnosis (OR = 1.27; P < 0.001). Larger tumor size (OR = 0.39; P = 0.001), stages II-IV or unstageable disease (OR = 0.56; P < 0.001), positive surgical margins or margins that were unevaluable (OR = 0.87; P = 0.009) and receipt of systemic therapy (OR = 0.85; P = 0.016) were associated with a lower likelihood of survival. Conclusions: Our study reiterated that females with ULMS had worse OS than those with EULMS. this difference can be attributed to certain clinical risk factors, however, it may also be secondary to genetic and epigenetic factors. Surprisingly, the use of palliative care in this study was associated with poorer OS in the EULMS group. Further studies are needed to investigate the genetic map of these diseases and highlight certain potentially targetable prognostic and predictive factors. Study limitations: Our study did not stratify ULMS and EULMS according to the stage to examine if the aforementioned factors would still be relevant in the limited versus metastatic setting.

Differential risk factors between uterine sarcomas and malignant mixed Müllerian tumors

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Background: Uterine sarcomas are malignant tumors of the smooth muscle or connective tissue of the uterus. Its main histological types are leiomyosarcomas and endometrial stromal sarcomas, with recent classifications considering malignant mixed müllerian tumors (MMMT) as a dedifferentiated endometrial carcinoma rather than a primary uterine sarcoma. We hypothesize there are different risk factors which predispose to MMMT as compared to uterine sarcomas. This study investigates these risk factors to determine if they contribute to the development of either disease. Methods: Under an IRB-approved protocol, we identified patients with uterine sarcomas and MMMT treated at Sylvester Comprehensive Cancer Center and University of Miami Hospital between 2010 and 2020 by Patient Atlas (clinical database tool; Miami, FL). We compared the risk factors known to be associated with endometrial carcinomas between uterine sarcomas and MMMT using independent sample t-test, Chi Square, Spearman Rho and Pearson correlation. Results: A total of 59 patients with MMMT and 115 cases of uterine sarcoma were identified in our database. In the sarcoma group, the most common histology was leiomyosarcoma (n = 76, 66%). Upon analysis of the characteristics of the sarcoma and MMMT cohorts respectively, 38 (33%) vs 16 (27%) were Hispanics, 18 (15%) vs 13 (22%) had diabetes, 26 (22%) vs 20 (34%) used contraception or hormonal replacement therapy (HRT), 35 (30%) vs 17 (28%) were alcohol users, 26 (22%) vs 15 (25%) were smokers, and 54 (47%) vs 31 (52%) had a positive family history of cancer, with no statistically significant differences found (p > 0.05). The sarcoma group had a significantly lower age at diagnosis (AAD) (53 vs. 65, P < 0.001) and a larger tumor size (11.3 vs. 7.3 cm, p < 0.0005). Use of contraception or HRT was not significantly different among the 2 groups (χ(1) = 0.699, p = 0.4). Similarly, no significant difference was found in the mean age of menarche/menopause, patient’s weight, median gravidity and parity (p > 0.05). The patient’s weight and BMI negatively correlated with the AAD in the MMMT group (ρ = - 0.279, p = 0.043 and r = -0.274, p = 0.041 respectively). Older age at menopause was associated with older AAD in the sarcoma group (ρ = 0.571, p = 0.0001). Patients with higher gravidity and parity had an older AAD among the 2 groups (p ≤ 0.05). Conclusions: The uterine sarcoma patients had significantly younger AAD than the MMMT group, with the age at menopause being positively correlated with the AAD. The use of contraception or HRT were not significantly different among the 2 cohorts, suggesting that there could be an overlap of the risk factors of MMMT and uterine sarcomas. Interestingly, higher gravidity and parity were associated with an older AAD. In the MMMT group, patient’s weight and BMI were inversely associated with the AAD. Larger studies are needed to investigate whether similarities or discrepancies in the studied risk factors truly exist.

Uterine sarcomas, insight into its risk factors: A systematic review

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Background: Uterine sarcomas are rare and aggressive malignant tumors that arise from the smooth muscle or connective tissue cells of the uterus. They account for approximately 1% of the female tract malignancies and 3% of all malignant tumors of the uterus. The risk factors that would predispose to uterine sarcomas have always been unknown, with no clear correlation with specific etiologies. This review is to investigate the risk factors that have been looked at by prior studies to have a better understanding of the population at higher risk for uterine sarcomas. Methods: A total of 88 studies were obtained via Pubmed search. The search terms included: Uterus, sarcoma, and risk factors. We also included reviews with the following mesh terms: Uterus, Sarcoma, Etiology and factors. We reviewed studies in English (n = 75) and French (n = 4) languages, human studies and comprising adults. We included only studies with electronic copies. Retrospective, case-control studies and systematic reviews were included. Results: Of the 88 studies, 18 mentioned risk factors and demographic characteristics of the population with uterine sarcomas. Some studies have shown an association with the tumor size – especially more than or equal to 8cm-, uterine weight, patient’s age being > 45-50 years old, age at menarche, obesity, tamoxifen use, previous pelvic irradiation, as well as genetic associations. Mixed evidence has been found regarding the role of the ethnicity, age at menopause, age at first live birth and exogenous estrogen use. Breast cancer has been linked to more aggressive histologic cell types. Conclusions: Given its relatively rare incidence, uterine sarcoma has been mysterious in regards to its risk factors. The results of this review highlight the need for further studies to investigate the risk factors and exposures that may lead to development of uterine sarcomas, as well as linking them to the different histologic types.